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kernel/drivers/ata/libata-sff.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* libata-sff.c - helper library for PCI IDE BMDMA
*
* Copyright 2003-2006 Red Hat, Inc. All rights reserved.
* Copyright 2003-2006 Jeff Garzik
*
* libata documentation is available via 'make {ps|pdf}docs',
* as Documentation/driver-api/libata.rst
*
* Hardware documentation available from http://www.t13.org/ and
* http://www.sata-io.org/
*/
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/pci.h>
#include <linux/module.h>
#include <linux/libata.h>
#include <linux/highmem.h>
#include <trace/events/libata.h>
#include "libata.h"
static struct workqueue_struct *ata_sff_wq;
const struct ata_port_operations ata_sff_port_ops = {
.inherits = &ata_base_port_ops,
.qc_issue = ata_sff_qc_issue,
.qc_fill_rtf = ata_sff_qc_fill_rtf,
.freeze = ata_sff_freeze,
.thaw = ata_sff_thaw,
.prereset = ata_sff_prereset,
.softreset = ata_sff_softreset,
.hardreset = sata_sff_hardreset,
.postreset = ata_sff_postreset,
.error_handler = ata_sff_error_handler,
.sff_dev_select = ata_sff_dev_select,
.sff_check_status = ata_sff_check_status,
.sff_tf_load = ata_sff_tf_load,
.sff_tf_read = ata_sff_tf_read,
.sff_exec_command = ata_sff_exec_command,
.sff_data_xfer = ata_sff_data_xfer,
.sff_drain_fifo = ata_sff_drain_fifo,
.lost_interrupt = ata_sff_lost_interrupt,
};
EXPORT_SYMBOL_GPL(ata_sff_port_ops);
/**
* ata_sff_check_status - Read device status reg & clear interrupt
* @ap: port where the device is
*
* Reads ATA taskfile status register for currently-selected device
* and return its value. This also clears pending interrupts
* from this device
*
* LOCKING:
* Inherited from caller.
*/
u8 ata_sff_check_status(struct ata_port *ap)
{
return ioread8(ap->ioaddr.status_addr);
}
EXPORT_SYMBOL_GPL(ata_sff_check_status);
/**
* ata_sff_altstatus - Read device alternate status reg
* @ap: port where the device is
* @status: pointer to a status value
*
* Reads ATA alternate status register for currently-selected device
* and return its value.
*
* RETURN:
* true if the register exists, false if not.
*
* LOCKING:
* Inherited from caller.
*/
static bool ata_sff_altstatus(struct ata_port *ap, u8 *status)
{
u8 tmp;
if (ap->ops->sff_check_altstatus) {
tmp = ap->ops->sff_check_altstatus(ap);
goto read;
}
if (ap->ioaddr.altstatus_addr) {
tmp = ioread8(ap->ioaddr.altstatus_addr);
goto read;
}
return false;
read:
if (status)
*status = tmp;
return true;
}
/**
* ata_sff_irq_status - Check if the device is busy
* @ap: port where the device is
*
* Determine if the port is currently busy. Uses altstatus
* if available in order to avoid clearing shared IRQ status
* when finding an IRQ source. Non ctl capable devices don't
* share interrupt lines fortunately for us.
*
* LOCKING:
* Inherited from caller.
*/
static u8 ata_sff_irq_status(struct ata_port *ap)
{
u8 status;
/* Not us: We are busy */
if (ata_sff_altstatus(ap, &status) && (status & ATA_BUSY))
return status;
/* Clear INTRQ latch */
status = ap->ops->sff_check_status(ap);
return status;
}
/**
* ata_sff_sync - Flush writes
* @ap: Port to wait for.
*
* CAUTION:
* If we have an mmio device with no ctl and no altstatus
* method this will fail. No such devices are known to exist.
*
* LOCKING:
* Inherited from caller.
*/
static void ata_sff_sync(struct ata_port *ap)
{
ata_sff_altstatus(ap, NULL);
}
/**
* ata_sff_pause - Flush writes and wait 400nS
* @ap: Port to pause for.
*
* CAUTION:
* If we have an mmio device with no ctl and no altstatus
* method this will fail. No such devices are known to exist.
*
* LOCKING:
* Inherited from caller.
*/
void ata_sff_pause(struct ata_port *ap)
{
ata_sff_sync(ap);
ndelay(400);
}
EXPORT_SYMBOL_GPL(ata_sff_pause);
/**
* ata_sff_dma_pause - Pause before commencing DMA
* @ap: Port to pause for.
*
* Perform I/O fencing and ensure sufficient cycle delays occur
* for the HDMA1:0 transition
*/
void ata_sff_dma_pause(struct ata_port *ap)
{
/*
* An altstatus read will cause the needed delay without
* messing up the IRQ status
*/
if (ata_sff_altstatus(ap, NULL))
return;
/* There are no DMA controllers without ctl. BUG here to ensure
we never violate the HDMA1:0 transition timing and risk
corruption. */
BUG();
}
EXPORT_SYMBOL_GPL(ata_sff_dma_pause);
static int ata_sff_check_ready(struct ata_link *link)
{
u8 status = link->ap->ops->sff_check_status(link->ap);
return ata_check_ready(status);
}
/**
* ata_sff_wait_ready - sleep until BSY clears, or timeout
* @link: SFF link to wait ready status for
* @deadline: deadline jiffies for the operation
*
* Sleep until ATA Status register bit BSY clears, or timeout
* occurs.
*
* LOCKING:
* Kernel thread context (may sleep).
*
* RETURNS:
* 0 on success, -errno otherwise.
*/
int ata_sff_wait_ready(struct ata_link *link, unsigned long deadline)
{
return ata_wait_ready(link, deadline, ata_sff_check_ready);
}
EXPORT_SYMBOL_GPL(ata_sff_wait_ready);
/**
* ata_sff_set_devctl - Write device control reg
* @ap: port where the device is
* @ctl: value to write
*
* Writes ATA device control register.
*
* RETURN:
* true if the register exists, false if not.
*
* LOCKING:
* Inherited from caller.
*/
static bool ata_sff_set_devctl(struct ata_port *ap, u8 ctl)
{
if (ap->ops->sff_set_devctl) {
ap->ops->sff_set_devctl(ap, ctl);
return true;
}
if (ap->ioaddr.ctl_addr) {
iowrite8(ctl, ap->ioaddr.ctl_addr);
return true;
}
return false;
}
/**
* ata_sff_dev_select - Select device 0/1 on ATA bus
* @ap: ATA channel to manipulate
* @device: ATA device (numbered from zero) to select
*
* Use the method defined in the ATA specification to
* make either device 0, or device 1, active on the
* ATA channel. Works with both PIO and MMIO.
*
* May be used as the dev_select() entry in ata_port_operations.
*
* LOCKING:
* caller.
*/
void ata_sff_dev_select(struct ata_port *ap, unsigned int device)
{
u8 tmp;
if (device == 0)
tmp = ATA_DEVICE_OBS;
else
tmp = ATA_DEVICE_OBS | ATA_DEV1;
iowrite8(tmp, ap->ioaddr.device_addr);
ata_sff_pause(ap); /* needed; also flushes, for mmio */
}
EXPORT_SYMBOL_GPL(ata_sff_dev_select);
/**
* ata_dev_select - Select device 0/1 on ATA bus
* @ap: ATA channel to manipulate
* @device: ATA device (numbered from zero) to select
* @wait: non-zero to wait for Status register BSY bit to clear
* @can_sleep: non-zero if context allows sleeping
*
* Use the method defined in the ATA specification to
* make either device 0, or device 1, active on the
* ATA channel.
*
* This is a high-level version of ata_sff_dev_select(), which
* additionally provides the services of inserting the proper
* pauses and status polling, where needed.
*
* LOCKING:
* caller.
*/
static void ata_dev_select(struct ata_port *ap, unsigned int device,
unsigned int wait, unsigned int can_sleep)
{
if (wait)
ata_wait_idle(ap);
ap->ops->sff_dev_select(ap, device);
if (wait) {
if (can_sleep && ap->link.device[device].class == ATA_DEV_ATAPI)
ata_msleep(ap, 150);
ata_wait_idle(ap);
}
}
/**
* ata_sff_irq_on - Enable interrupts on a port.
* @ap: Port on which interrupts are enabled.
*
* Enable interrupts on a legacy IDE device using MMIO or PIO,
* wait for idle, clear any pending interrupts.
*
* Note: may NOT be used as the sff_irq_on() entry in
* ata_port_operations.
*
* LOCKING:
* Inherited from caller.
*/
void ata_sff_irq_on(struct ata_port *ap)
{
if (ap->ops->sff_irq_on) {
ap->ops->sff_irq_on(ap);
return;
}
ap->ctl &= ~ATA_NIEN;
ap->last_ctl = ap->ctl;
ata_sff_set_devctl(ap, ap->ctl);
ata_wait_idle(ap);
if (ap->ops->sff_irq_clear)
ap->ops->sff_irq_clear(ap);
}
EXPORT_SYMBOL_GPL(ata_sff_irq_on);
/**
* ata_sff_tf_load - send taskfile registers to host controller
* @ap: Port to which output is sent
* @tf: ATA taskfile register set
*
* Outputs ATA taskfile to standard ATA host controller.
*
* LOCKING:
* Inherited from caller.
*/
void ata_sff_tf_load(struct ata_port *ap, const struct ata_taskfile *tf)
{
struct ata_ioports *ioaddr = &ap->ioaddr;
unsigned int is_addr = tf->flags & ATA_TFLAG_ISADDR;
if (tf->ctl != ap->last_ctl) {
if (ioaddr->ctl_addr)
iowrite8(tf->ctl, ioaddr->ctl_addr);
ap->last_ctl = tf->ctl;
ata_wait_idle(ap);
}
if (is_addr && (tf->flags & ATA_TFLAG_LBA48)) {
WARN_ON_ONCE(!ioaddr->ctl_addr);
iowrite8(tf->hob_feature, ioaddr->feature_addr);
iowrite8(tf->hob_nsect, ioaddr->nsect_addr);
iowrite8(tf->hob_lbal, ioaddr->lbal_addr);
iowrite8(tf->hob_lbam, ioaddr->lbam_addr);
iowrite8(tf->hob_lbah, ioaddr->lbah_addr);
}
if (is_addr) {
iowrite8(tf->feature, ioaddr->feature_addr);
iowrite8(tf->nsect, ioaddr->nsect_addr);
iowrite8(tf->lbal, ioaddr->lbal_addr);
iowrite8(tf->lbam, ioaddr->lbam_addr);
iowrite8(tf->lbah, ioaddr->lbah_addr);
}
if (tf->flags & ATA_TFLAG_DEVICE)
iowrite8(tf->device, ioaddr->device_addr);
ata_wait_idle(ap);
}
EXPORT_SYMBOL_GPL(ata_sff_tf_load);
/**
* ata_sff_tf_read - input device's ATA taskfile shadow registers
* @ap: Port from which input is read
* @tf: ATA taskfile register set for storing input
*
* Reads ATA taskfile registers for currently-selected device
* into @tf. Assumes the device has a fully SFF compliant task file
* layout and behaviour. If you device does not (eg has a different
* status method) then you will need to provide a replacement tf_read
*
* LOCKING:
* Inherited from caller.
*/
void ata_sff_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
{
struct ata_ioports *ioaddr = &ap->ioaddr;
tf->status = ata_sff_check_status(ap);
tf->error = ioread8(ioaddr->error_addr);
tf->nsect = ioread8(ioaddr->nsect_addr);
tf->lbal = ioread8(ioaddr->lbal_addr);
tf->lbam = ioread8(ioaddr->lbam_addr);
tf->lbah = ioread8(ioaddr->lbah_addr);
tf->device = ioread8(ioaddr->device_addr);
if (tf->flags & ATA_TFLAG_LBA48) {
if (likely(ioaddr->ctl_addr)) {
iowrite8(tf->ctl | ATA_HOB, ioaddr->ctl_addr);
tf->hob_feature = ioread8(ioaddr->error_addr);
tf->hob_nsect = ioread8(ioaddr->nsect_addr);
tf->hob_lbal = ioread8(ioaddr->lbal_addr);
tf->hob_lbam = ioread8(ioaddr->lbam_addr);
tf->hob_lbah = ioread8(ioaddr->lbah_addr);
iowrite8(tf->ctl, ioaddr->ctl_addr);
ap->last_ctl = tf->ctl;
} else
WARN_ON_ONCE(1);
}
}
EXPORT_SYMBOL_GPL(ata_sff_tf_read);
/**
* ata_sff_exec_command - issue ATA command to host controller
* @ap: port to which command is being issued
* @tf: ATA taskfile register set
*
* Issues ATA command, with proper synchronization with interrupt
* handler / other threads.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
void ata_sff_exec_command(struct ata_port *ap, const struct ata_taskfile *tf)
{
iowrite8(tf->command, ap->ioaddr.command_addr);
ata_sff_pause(ap);
}
EXPORT_SYMBOL_GPL(ata_sff_exec_command);
/**
* ata_tf_to_host - issue ATA taskfile to host controller
* @ap: port to which command is being issued
* @tf: ATA taskfile register set
* @tag: tag of the associated command
*
* Issues ATA taskfile register set to ATA host controller,
* with proper synchronization with interrupt handler and
* other threads.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
static inline void ata_tf_to_host(struct ata_port *ap,
const struct ata_taskfile *tf,
unsigned int tag)
{
trace_ata_tf_load(ap, tf);
ap->ops->sff_tf_load(ap, tf);
trace_ata_exec_command(ap, tf, tag);
ap->ops->sff_exec_command(ap, tf);
}
/**
* ata_sff_data_xfer - Transfer data by PIO
* @qc: queued command
* @buf: data buffer
* @buflen: buffer length
* @rw: read/write
*
* Transfer data from/to the device data register by PIO.
*
* LOCKING:
* Inherited from caller.
*
* RETURNS:
* Bytes consumed.
*/
unsigned int ata_sff_data_xfer(struct ata_queued_cmd *qc, unsigned char *buf,
unsigned int buflen, int rw)
{
struct ata_port *ap = qc->dev->link->ap;
void __iomem *data_addr = ap->ioaddr.data_addr;
unsigned int words = buflen >> 1;
/* Transfer multiple of 2 bytes */
if (rw == READ)
ioread16_rep(data_addr, buf, words);
else
iowrite16_rep(data_addr, buf, words);
/* Transfer trailing byte, if any. */
if (unlikely(buflen & 0x01)) {
unsigned char pad[2] = { };
/* Point buf to the tail of buffer */
buf += buflen - 1;
/*
* Use io*16_rep() accessors here as well to avoid pointlessly
* swapping bytes to and from on the big endian machines...
*/
if (rw == READ) {
ioread16_rep(data_addr, pad, 1);
*buf = pad[0];
} else {
pad[0] = *buf;
iowrite16_rep(data_addr, pad, 1);
}
words++;
}
return words << 1;
}
EXPORT_SYMBOL_GPL(ata_sff_data_xfer);
/**
* ata_sff_data_xfer32 - Transfer data by PIO
* @qc: queued command
* @buf: data buffer
* @buflen: buffer length
* @rw: read/write
*
* Transfer data from/to the device data register by PIO using 32bit
* I/O operations.
*
* LOCKING:
* Inherited from caller.
*
* RETURNS:
* Bytes consumed.
*/
unsigned int ata_sff_data_xfer32(struct ata_queued_cmd *qc, unsigned char *buf,
unsigned int buflen, int rw)
{
struct ata_device *dev = qc->dev;
struct ata_port *ap = dev->link->ap;
void __iomem *data_addr = ap->ioaddr.data_addr;
unsigned int words = buflen >> 2;
int slop = buflen & 3;
if (!(ap->pflags & ATA_PFLAG_PIO32))
return ata_sff_data_xfer(qc, buf, buflen, rw);
/* Transfer multiple of 4 bytes */
if (rw == READ)
ioread32_rep(data_addr, buf, words);
else
iowrite32_rep(data_addr, buf, words);
/* Transfer trailing bytes, if any */
if (unlikely(slop)) {
unsigned char pad[4] = { };
/* Point buf to the tail of buffer */
buf += buflen - slop;
/*
* Use io*_rep() accessors here as well to avoid pointlessly
* swapping bytes to and from on the big endian machines...
*/
if (rw == READ) {
if (slop < 3)
ioread16_rep(data_addr, pad, 1);
else
ioread32_rep(data_addr, pad, 1);
memcpy(buf, pad, slop);
} else {
memcpy(pad, buf, slop);
if (slop < 3)
iowrite16_rep(data_addr, pad, 1);
else
iowrite32_rep(data_addr, pad, 1);
}
}
return (buflen + 1) & ~1;
}
EXPORT_SYMBOL_GPL(ata_sff_data_xfer32);
static void ata_pio_xfer(struct ata_queued_cmd *qc, struct page *page,
unsigned int offset, size_t xfer_size)
{
bool do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
unsigned char *buf;
buf = kmap_atomic(page);
qc->ap->ops->sff_data_xfer(qc, buf + offset, xfer_size, do_write);
kunmap_atomic(buf);
if (!do_write && !PageSlab(page))
flush_dcache_page(page);
}
/**
* ata_pio_sector - Transfer a sector of data.
* @qc: Command on going
*
* Transfer qc->sect_size bytes of data from/to the ATA device.
*
* LOCKING:
* Inherited from caller.
*/
static void ata_pio_sector(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
struct page *page;
unsigned int offset;
if (!qc->cursg) {
qc->curbytes = qc->nbytes;
return;
}
if (qc->curbytes == qc->nbytes - qc->sect_size)
ap->hsm_task_state = HSM_ST_LAST;
page = sg_page(qc->cursg);
offset = qc->cursg->offset + qc->cursg_ofs;
/* get the current page and offset */
page = nth_page(page, (offset >> PAGE_SHIFT));
offset %= PAGE_SIZE;
trace_ata_sff_pio_transfer_data(qc, offset, qc->sect_size);
/*
* Split the transfer when it splits a page boundary. Note that the
* split still has to be dword aligned like all ATA data transfers.
*/
WARN_ON_ONCE(offset % 4);
if (offset + qc->sect_size > PAGE_SIZE) {
unsigned int split_len = PAGE_SIZE - offset;
ata_pio_xfer(qc, page, offset, split_len);
ata_pio_xfer(qc, nth_page(page, 1), 0,
qc->sect_size - split_len);
} else {
ata_pio_xfer(qc, page, offset, qc->sect_size);
}
qc->curbytes += qc->sect_size;
qc->cursg_ofs += qc->sect_size;
if (qc->cursg_ofs == qc->cursg->length) {
qc->cursg = sg_next(qc->cursg);
if (!qc->cursg)
ap->hsm_task_state = HSM_ST_LAST;
qc->cursg_ofs = 0;
}
}
/**
* ata_pio_sectors - Transfer one or many sectors.
* @qc: Command on going
*
* Transfer one or many sectors of data from/to the
* ATA device for the DRQ request.
*
* LOCKING:
* Inherited from caller.
*/
static void ata_pio_sectors(struct ata_queued_cmd *qc)
{
if (is_multi_taskfile(&qc->tf)) {
/* READ/WRITE MULTIPLE */
unsigned int nsect;
WARN_ON_ONCE(qc->dev->multi_count == 0);
nsect = min((qc->nbytes - qc->curbytes) / qc->sect_size,
qc->dev->multi_count);
while (nsect--)
ata_pio_sector(qc);
} else
ata_pio_sector(qc);
ata_sff_sync(qc->ap); /* flush */
}
/**
* atapi_send_cdb - Write CDB bytes to hardware
* @ap: Port to which ATAPI device is attached.
* @qc: Taskfile currently active
*
* When device has indicated its readiness to accept
* a CDB, this function is called. Send the CDB.
*
* LOCKING:
* caller.
*/
static void atapi_send_cdb(struct ata_port *ap, struct ata_queued_cmd *qc)
{
/* send SCSI cdb */
trace_atapi_send_cdb(qc, 0, qc->dev->cdb_len);
WARN_ON_ONCE(qc->dev->cdb_len < 12);
ap->ops->sff_data_xfer(qc, qc->cdb, qc->dev->cdb_len, 1);
ata_sff_sync(ap);
/* FIXME: If the CDB is for DMA do we need to do the transition delay
or is bmdma_start guaranteed to do it ? */
switch (qc->tf.protocol) {
case ATAPI_PROT_PIO:
ap->hsm_task_state = HSM_ST;
break;
case ATAPI_PROT_NODATA:
ap->hsm_task_state = HSM_ST_LAST;
break;
#ifdef CONFIG_ATA_BMDMA
case ATAPI_PROT_DMA:
ap->hsm_task_state = HSM_ST_LAST;
/* initiate bmdma */
trace_ata_bmdma_start(ap, &qc->tf, qc->tag);
ap->ops->bmdma_start(qc);
break;
#endif /* CONFIG_ATA_BMDMA */
default:
BUG();
}
}
/**
* __atapi_pio_bytes - Transfer data from/to the ATAPI device.
* @qc: Command on going
* @bytes: number of bytes
*
* Transfer data from/to the ATAPI device.
*
* LOCKING:
* Inherited from caller.
*
*/
static int __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
{
int rw = (qc->tf.flags & ATA_TFLAG_WRITE) ? WRITE : READ;
struct ata_port *ap = qc->ap;
struct ata_device *dev = qc->dev;
struct ata_eh_info *ehi = &dev->link->eh_info;
struct scatterlist *sg;
struct page *page;
unsigned char *buf;
unsigned int offset, count, consumed;
next_sg:
sg = qc->cursg;
if (unlikely(!sg)) {
ata_ehi_push_desc(ehi, "unexpected or too much trailing data "
"buf=%u cur=%u bytes=%u",
qc->nbytes, qc->curbytes, bytes);
return -1;
}
page = sg_page(sg);
offset = sg->offset + qc->cursg_ofs;
/* get the current page and offset */
page = nth_page(page, (offset >> PAGE_SHIFT));
offset %= PAGE_SIZE;
/* don't overrun current sg */
count = min(sg->length - qc->cursg_ofs, bytes);
/* don't cross page boundaries */
count = min(count, (unsigned int)PAGE_SIZE - offset);
trace_atapi_pio_transfer_data(qc, offset, count);
/* do the actual data transfer */
buf = kmap_atomic(page);
consumed = ap->ops->sff_data_xfer(qc, buf + offset, count, rw);
kunmap_atomic(buf);
bytes -= min(bytes, consumed);
qc->curbytes += count;
qc->cursg_ofs += count;
if (qc->cursg_ofs == sg->length) {
qc->cursg = sg_next(qc->cursg);
qc->cursg_ofs = 0;
}
/*
* There used to be a WARN_ON_ONCE(qc->cursg && count != consumed);
* Unfortunately __atapi_pio_bytes doesn't know enough to do the WARN
* check correctly as it doesn't know if it is the last request being
* made. Somebody should implement a proper sanity check.
*/
if (bytes)
goto next_sg;
return 0;
}
/**
* atapi_pio_bytes - Transfer data from/to the ATAPI device.
* @qc: Command on going
*
* Transfer Transfer data from/to the ATAPI device.
*
* LOCKING:
* Inherited from caller.
*/
static void atapi_pio_bytes(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
struct ata_device *dev = qc->dev;
struct ata_eh_info *ehi = &dev->link->eh_info;
unsigned int ireason, bc_lo, bc_hi, bytes;
int i_write, do_write = (qc->tf.flags & ATA_TFLAG_WRITE) ? 1 : 0;
/* Abuse qc->result_tf for temp storage of intermediate TF
* here to save some kernel stack usage.
* For normal completion, qc->result_tf is not relevant. For
* error, qc->result_tf is later overwritten by ata_qc_complete().
* So, the correctness of qc->result_tf is not affected.
*/
ap->ops->sff_tf_read(ap, &qc->result_tf);
ireason = qc->result_tf.nsect;
bc_lo = qc->result_tf.lbam;
bc_hi = qc->result_tf.lbah;
bytes = (bc_hi << 8) | bc_lo;
/* shall be cleared to zero, indicating xfer of data */
if (unlikely(ireason & ATAPI_COD))
goto atapi_check;
/* make sure transfer direction matches expected */
i_write = ((ireason & ATAPI_IO) == 0) ? 1 : 0;
if (unlikely(do_write != i_write))
goto atapi_check;
if (unlikely(!bytes))
goto atapi_check;
if (unlikely(__atapi_pio_bytes(qc, bytes)))
goto err_out;
ata_sff_sync(ap); /* flush */
return;
atapi_check:
ata_ehi_push_desc(ehi, "ATAPI check failed (ireason=0x%x bytes=%u)",
ireason, bytes);
err_out:
qc->err_mask |= AC_ERR_HSM;
ap->hsm_task_state = HSM_ST_ERR;
}
/**
* ata_hsm_ok_in_wq - Check if the qc can be handled in the workqueue.
* @ap: the target ata_port
* @qc: qc on going
*
* RETURNS:
* 1 if ok in workqueue, 0 otherwise.
*/
static inline int ata_hsm_ok_in_wq(struct ata_port *ap,
struct ata_queued_cmd *qc)
{
if (qc->tf.flags & ATA_TFLAG_POLLING)
return 1;
if (ap->hsm_task_state == HSM_ST_FIRST) {
if (qc->tf.protocol == ATA_PROT_PIO &&
(qc->tf.flags & ATA_TFLAG_WRITE))
return 1;
if (ata_is_atapi(qc->tf.protocol) &&
!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
return 1;
}
return 0;
}
/**
* ata_hsm_qc_complete - finish a qc running on standard HSM
* @qc: Command to complete
* @in_wq: 1 if called from workqueue, 0 otherwise
*
* Finish @qc which is running on standard HSM.
*
* LOCKING:
* If @in_wq is zero, spin_lock_irqsave(host lock).
* Otherwise, none on entry and grabs host lock.
*/
static void ata_hsm_qc_complete(struct ata_queued_cmd *qc, int in_wq)
{
struct ata_port *ap = qc->ap;
if (ap->ops->error_handler) {
if (in_wq) {
/* EH might have kicked in while host lock is
* released.
*/
qc = ata_qc_from_tag(ap, qc->tag);
if (qc) {
if (likely(!(qc->err_mask & AC_ERR_HSM))) {
ata_sff_irq_on(ap);
ata_qc_complete(qc);
} else
ata_port_freeze(ap);
}
} else {
if (likely(!(qc->err_mask & AC_ERR_HSM)))
ata_qc_complete(qc);
else
ata_port_freeze(ap);
}
} else {
if (in_wq) {
ata_sff_irq_on(ap);
ata_qc_complete(qc);
} else
ata_qc_complete(qc);
}
}
/**
* ata_sff_hsm_move - move the HSM to the next state.
* @ap: the target ata_port
* @qc: qc on going
* @status: current device status
* @in_wq: 1 if called from workqueue, 0 otherwise
*
* RETURNS:
* 1 when poll next status needed, 0 otherwise.
*/
int ata_sff_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
u8 status, int in_wq)
{
struct ata_link *link = qc->dev->link;
struct ata_eh_info *ehi = &link->eh_info;
int poll_next;
lockdep_assert_held(ap->lock);
WARN_ON_ONCE((qc->flags & ATA_QCFLAG_ACTIVE) == 0);
/* Make sure ata_sff_qc_issue() does not throw things
* like DMA polling into the workqueue. Notice that
* in_wq is not equivalent to (qc->tf.flags & ATA_TFLAG_POLLING).
*/
WARN_ON_ONCE(in_wq != ata_hsm_ok_in_wq(ap, qc));
fsm_start:
trace_ata_sff_hsm_state(qc, status);
switch (ap->hsm_task_state) {
case HSM_ST_FIRST:
/* Send first data block or PACKET CDB */
/* If polling, we will stay in the work queue after
* sending the data. Otherwise, interrupt handler
* takes over after sending the data.
*/
poll_next = (qc->tf.flags & ATA_TFLAG_POLLING);
/* check device status */
if (unlikely((status & ATA_DRQ) == 0)) {
/* handle BSY=0, DRQ=0 as error */
if (likely(status & (ATA_ERR | ATA_DF)))
/* device stops HSM for abort/error */
qc->err_mask |= AC_ERR_DEV;
else {
/* HSM violation. Let EH handle this */
ata_ehi_push_desc(ehi,
"ST_FIRST: !(DRQ|ERR|DF)");
qc->err_mask |= AC_ERR_HSM;
}
ap->hsm_task_state = HSM_ST_ERR;
goto fsm_start;
}
/* Device should not ask for data transfer (DRQ=1)
* when it finds something wrong.
* We ignore DRQ here and stop the HSM by
* changing hsm_task_state to HSM_ST_ERR and
* let the EH abort the command or reset the device.
*/
if (unlikely(status & (ATA_ERR | ATA_DF))) {
/* Some ATAPI tape drives forget to clear the ERR bit
* when doing the next command (mostly request sense).
* We ignore ERR here to workaround and proceed sending
* the CDB.
*/
if (!(qc->dev->horkage & ATA_HORKAGE_STUCK_ERR)) {
ata_ehi_push_desc(ehi, "ST_FIRST: "
"DRQ=1 with device error, "
"dev_stat 0x%X", status);
qc->err_mask |= AC_ERR_HSM;
ap->hsm_task_state = HSM_ST_ERR;
goto fsm_start;
}
}
if (qc->tf.protocol == ATA_PROT_PIO) {
/* PIO data out protocol.
* send first data block.
*/
/* ata_pio_sectors() might change the state
* to HSM_ST_LAST. so, the state is changed here
* before ata_pio_sectors().
*/
ap->hsm_task_state = HSM_ST;
ata_pio_sectors(qc);
} else
/* send CDB */
atapi_send_cdb(ap, qc);
/* if polling, ata_sff_pio_task() handles the rest.
* otherwise, interrupt handler takes over from here.
*/
break;
case HSM_ST:
/* complete command or read/write the data register */
if (qc->tf.protocol == ATAPI_PROT_PIO) {
/* ATAPI PIO protocol */
if ((status & ATA_DRQ) == 0) {
/* No more data to transfer or device error.
* Device error will be tagged in HSM_ST_LAST.
*/
ap->hsm_task_state = HSM_ST_LAST;
goto fsm_start;
}
/* Device should not ask for data transfer (DRQ=1)
* when it finds something wrong.
* We ignore DRQ here and stop the HSM by
* changing hsm_task_state to HSM_ST_ERR and
* let the EH abort the command or reset the device.
*/
if (unlikely(status & (ATA_ERR | ATA_DF))) {
ata_ehi_push_desc(ehi, "ST-ATAPI: "
"DRQ=1 with device error, "
"dev_stat 0x%X", status);
qc->err_mask |= AC_ERR_HSM;
ap->hsm_task_state = HSM_ST_ERR;
goto fsm_start;
}
atapi_pio_bytes(qc);
if (unlikely(ap->hsm_task_state == HSM_ST_ERR))
/* bad ireason reported by device */
goto fsm_start;
} else {
/* ATA PIO protocol */
if (unlikely((status & ATA_DRQ) == 0)) {
/* handle BSY=0, DRQ=0 as error */
if (likely(status & (ATA_ERR | ATA_DF))) {
/* device stops HSM for abort/error */
qc->err_mask |= AC_ERR_DEV;
/* If diagnostic failed and this is
* IDENTIFY, it's likely a phantom
* device. Mark hint.
*/
if (qc->dev->horkage &
ATA_HORKAGE_DIAGNOSTIC)
qc->err_mask |=
AC_ERR_NODEV_HINT;
} else {
/* HSM violation. Let EH handle this.
* Phantom devices also trigger this
* condition. Mark hint.
*/
ata_ehi_push_desc(ehi, "ST-ATA: "
"DRQ=0 without device error, "
"dev_stat 0x%X", status);
qc->err_mask |= AC_ERR_HSM |
AC_ERR_NODEV_HINT;
}
ap->hsm_task_state = HSM_ST_ERR;
goto fsm_start;
}
/* For PIO reads, some devices may ask for
* data transfer (DRQ=1) alone with ERR=1.
* We respect DRQ here and transfer one
* block of junk data before changing the
* hsm_task_state to HSM_ST_ERR.
*
* For PIO writes, ERR=1 DRQ=1 doesn't make
* sense since the data block has been
* transferred to the device.
*/
if (unlikely(status & (ATA_ERR | ATA_DF))) {
/* data might be corrputed */
qc->err_mask |= AC_ERR_DEV;
if (!(qc->tf.flags & ATA_TFLAG_WRITE)) {
ata_pio_sectors(qc);
status = ata_wait_idle(ap);
}
if (status & (ATA_BUSY | ATA_DRQ)) {
ata_ehi_push_desc(ehi, "ST-ATA: "
"BUSY|DRQ persists on ERR|DF, "
"dev_stat 0x%X", status);
qc->err_mask |= AC_ERR_HSM;
}
/* There are oddball controllers with
* status register stuck at 0x7f and
* lbal/m/h at zero which makes it
* pass all other presence detection
* mechanisms we have. Set NODEV_HINT
* for it. Kernel bz#7241.
*/
if (status == 0x7f)
qc->err_mask |= AC_ERR_NODEV_HINT;
/* ata_pio_sectors() might change the
* state to HSM_ST_LAST. so, the state
* is changed after ata_pio_sectors().
*/
ap->hsm_task_state = HSM_ST_ERR;
goto fsm_start;
}
ata_pio_sectors(qc);
if (ap->hsm_task_state == HSM_ST_LAST &&
(!(qc->tf.flags & ATA_TFLAG_WRITE))) {
/* all data read */
status = ata_wait_idle(ap);
goto fsm_start;
}
}
poll_next = 1;
break;
case HSM_ST_LAST:
if (unlikely(!ata_ok(status))) {
qc->err_mask |= __ac_err_mask(status);
ap->hsm_task_state = HSM_ST_ERR;
goto fsm_start;
}
/* no more data to transfer */
trace_ata_sff_hsm_command_complete(qc, status);
WARN_ON_ONCE(qc->err_mask & (AC_ERR_DEV | AC_ERR_HSM));
ap->hsm_task_state = HSM_ST_IDLE;
/* complete taskfile transaction */
ata_hsm_qc_complete(qc, in_wq);
poll_next = 0;
break;
case HSM_ST_ERR:
ap->hsm_task_state = HSM_ST_IDLE;
/* complete taskfile transaction */
ata_hsm_qc_complete(qc, in_wq);
poll_next = 0;
break;
default:
poll_next = 0;
WARN(true, "ata%d: SFF host state machine in invalid state %d",
ap->print_id, ap->hsm_task_state);
}
return poll_next;
}
EXPORT_SYMBOL_GPL(ata_sff_hsm_move);
void ata_sff_queue_work(struct work_struct *work)
{
queue_work(ata_sff_wq, work);
}
EXPORT_SYMBOL_GPL(ata_sff_queue_work);
void ata_sff_queue_delayed_work(struct delayed_work *dwork, unsigned long delay)
{
queue_delayed_work(ata_sff_wq, dwork, delay);
}
EXPORT_SYMBOL_GPL(ata_sff_queue_delayed_work);
void ata_sff_queue_pio_task(struct ata_link *link, unsigned long delay)
{
struct ata_port *ap = link->ap;
WARN_ON((ap->sff_pio_task_link != NULL) &&
(ap->sff_pio_task_link != link));
ap->sff_pio_task_link = link;
/* may fail if ata_sff_flush_pio_task() in progress */
ata_sff_queue_delayed_work(&ap->sff_pio_task, msecs_to_jiffies(delay));
}
EXPORT_SYMBOL_GPL(ata_sff_queue_pio_task);
void ata_sff_flush_pio_task(struct ata_port *ap)
{
trace_ata_sff_flush_pio_task(ap);
cancel_delayed_work_sync(&ap->sff_pio_task);
/*
* We wanna reset the HSM state to IDLE. If we do so without
* grabbing the port lock, critical sections protected by it which
* expect the HSM state to stay stable may get surprised. For
* example, we may set IDLE in between the time
* __ata_sff_port_intr() checks for HSM_ST_IDLE and before it calls
* ata_sff_hsm_move() causing ata_sff_hsm_move() to BUG().
*/
spin_lock_irq(ap->lock);
ap->hsm_task_state = HSM_ST_IDLE;
spin_unlock_irq(ap->lock);
ap->sff_pio_task_link = NULL;
}
static void ata_sff_pio_task(struct work_struct *work)
{
struct ata_port *ap =
container_of(work, struct ata_port, sff_pio_task.work);
struct ata_link *link = ap->sff_pio_task_link;
struct ata_queued_cmd *qc;
u8 status;
int poll_next;
spin_lock_irq(ap->lock);
BUG_ON(ap->sff_pio_task_link == NULL);
/* qc can be NULL if timeout occurred */
qc = ata_qc_from_tag(ap, link->active_tag);
if (!qc) {
ap->sff_pio_task_link = NULL;
goto out_unlock;
}
fsm_start:
WARN_ON_ONCE(ap->hsm_task_state == HSM_ST_IDLE);
/*
* This is purely heuristic. This is a fast path.
* Sometimes when we enter, BSY will be cleared in
* a chk-status or two. If not, the drive is probably seeking
* or something. Snooze for a couple msecs, then
* chk-status again. If still busy, queue delayed work.
*/
status = ata_sff_busy_wait(ap, ATA_BUSY, 5);
if (status & ATA_BUSY) {
spin_unlock_irq(ap->lock);
ata_msleep(ap, 2);
spin_lock_irq(ap->lock);
status = ata_sff_busy_wait(ap, ATA_BUSY, 10);
if (status & ATA_BUSY) {
ata_sff_queue_pio_task(link, ATA_SHORT_PAUSE);
goto out_unlock;
}
}
/*
* hsm_move() may trigger another command to be processed.
* clean the link beforehand.
*/
ap->sff_pio_task_link = NULL;
/* move the HSM */
poll_next = ata_sff_hsm_move(ap, qc, status, 1);
/* another command or interrupt handler
* may be running at this point.
*/
if (poll_next)
goto fsm_start;
out_unlock:
spin_unlock_irq(ap->lock);
}
/**
* ata_sff_qc_issue - issue taskfile to a SFF controller
* @qc: command to issue to device
*
* This function issues a PIO or NODATA command to a SFF
* controller.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*
* RETURNS:
* Zero on success, AC_ERR_* mask on failure
*/
unsigned int ata_sff_qc_issue(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
struct ata_link *link = qc->dev->link;
/* Use polling pio if the LLD doesn't handle
* interrupt driven pio and atapi CDB interrupt.
*/
if (ap->flags & ATA_FLAG_PIO_POLLING)
qc->tf.flags |= ATA_TFLAG_POLLING;
/* select the device */
ata_dev_select(ap, qc->dev->devno, 1, 0);
/* start the command */
switch (qc->tf.protocol) {
case ATA_PROT_NODATA:
if (qc->tf.flags & ATA_TFLAG_POLLING)
ata_qc_set_polling(qc);
ata_tf_to_host(ap, &qc->tf, qc->tag);
ap->hsm_task_state = HSM_ST_LAST;
if (qc->tf.flags & ATA_TFLAG_POLLING)
ata_sff_queue_pio_task(link, 0);
break;
case ATA_PROT_PIO:
if (qc->tf.flags & ATA_TFLAG_POLLING)
ata_qc_set_polling(qc);
ata_tf_to_host(ap, &qc->tf, qc->tag);
if (qc->tf.flags & ATA_TFLAG_WRITE) {
/* PIO data out protocol */
ap->hsm_task_state = HSM_ST_FIRST;
ata_sff_queue_pio_task(link, 0);
/* always send first data block using the
* ata_sff_pio_task() codepath.
*/
} else {
/* PIO data in protocol */
ap->hsm_task_state = HSM_ST;
if (qc->tf.flags & ATA_TFLAG_POLLING)
ata_sff_queue_pio_task(link, 0);
/* if polling, ata_sff_pio_task() handles the
* rest. otherwise, interrupt handler takes
* over from here.
*/
}
break;
case ATAPI_PROT_PIO:
case ATAPI_PROT_NODATA:
if (qc->tf.flags & ATA_TFLAG_POLLING)
ata_qc_set_polling(qc);
ata_tf_to_host(ap, &qc->tf, qc->tag);
ap->hsm_task_state = HSM_ST_FIRST;
/* send cdb by polling if no cdb interrupt */
if ((!(qc->dev->flags & ATA_DFLAG_CDB_INTR)) ||
(qc->tf.flags & ATA_TFLAG_POLLING))
ata_sff_queue_pio_task(link, 0);
break;
default:
return AC_ERR_SYSTEM;
}
return 0;
}
EXPORT_SYMBOL_GPL(ata_sff_qc_issue);
/**
* ata_sff_qc_fill_rtf - fill result TF using ->sff_tf_read
* @qc: qc to fill result TF for
*
* @qc is finished and result TF needs to be filled. Fill it
* using ->sff_tf_read.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
void ata_sff_qc_fill_rtf(struct ata_queued_cmd *qc)
{
qc->ap->ops->sff_tf_read(qc->ap, &qc->result_tf);
}
EXPORT_SYMBOL_GPL(ata_sff_qc_fill_rtf);
static unsigned int ata_sff_idle_irq(struct ata_port *ap)
{
ap->stats.idle_irq++;
#ifdef ATA_IRQ_TRAP
if ((ap->stats.idle_irq % 1000) == 0) {
ap->ops->sff_check_status(ap);
if (ap->ops->sff_irq_clear)
ap->ops->sff_irq_clear(ap);
ata_port_warn(ap, "irq trap\n");
return 1;
}
#endif
return 0; /* irq not handled */
}
static unsigned int __ata_sff_port_intr(struct ata_port *ap,
struct ata_queued_cmd *qc,
bool hsmv_on_idle)
{
u8 status;
trace_ata_sff_port_intr(qc, hsmv_on_idle);
/* Check whether we are expecting interrupt in this state */
switch (ap->hsm_task_state) {
case HSM_ST_FIRST:
/* Some pre-ATAPI-4 devices assert INTRQ
* at this state when ready to receive CDB.
*/
/* Check the ATA_DFLAG_CDB_INTR flag is enough here.
* The flag was turned on only for atapi devices. No
* need to check ata_is_atapi(qc->tf.protocol) again.
*/
if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
return ata_sff_idle_irq(ap);
break;
case HSM_ST_IDLE:
return ata_sff_idle_irq(ap);
default:
break;
}
/* check main status, clearing INTRQ if needed */
status = ata_sff_irq_status(ap);
if (status & ATA_BUSY) {
if (hsmv_on_idle) {
/* BMDMA engine is already stopped, we're screwed */
qc->err_mask |= AC_ERR_HSM;
ap->hsm_task_state = HSM_ST_ERR;
} else
return ata_sff_idle_irq(ap);
}
/* clear irq events */
if (ap->ops->sff_irq_clear)
ap->ops->sff_irq_clear(ap);
ata_sff_hsm_move(ap, qc, status, 0);
return 1; /* irq handled */
}
/**
* ata_sff_port_intr - Handle SFF port interrupt
* @ap: Port on which interrupt arrived (possibly...)
* @qc: Taskfile currently active in engine
*
* Handle port interrupt for given queued command.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*
* RETURNS:
* One if interrupt was handled, zero if not (shared irq).
*/
unsigned int ata_sff_port_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
{
return __ata_sff_port_intr(ap, qc, false);
}
EXPORT_SYMBOL_GPL(ata_sff_port_intr);
static inline irqreturn_t __ata_sff_interrupt(int irq, void *dev_instance,
unsigned int (*port_intr)(struct ata_port *, struct ata_queued_cmd *))
{
struct ata_host *host = dev_instance;
bool retried = false;
unsigned int i;
unsigned int handled, idle, polling;
unsigned long flags;
/* TODO: make _irqsave conditional on x86 PCI IDE legacy mode */
spin_lock_irqsave(&host->lock, flags);
retry:
handled = idle = polling = 0;
for (i = 0; i < host->n_ports; i++) {
struct ata_port *ap = host->ports[i];
struct ata_queued_cmd *qc;
qc = ata_qc_from_tag(ap, ap->link.active_tag);
if (qc) {
if (!(qc->tf.flags & ATA_TFLAG_POLLING))
handled |= port_intr(ap, qc);
else
polling |= 1 << i;
} else
idle |= 1 << i;
}
/*
* If no port was expecting IRQ but the controller is actually
* asserting IRQ line, nobody cared will ensue. Check IRQ
* pending status if available and clear spurious IRQ.
*/
if (!handled && !retried) {
bool retry = false;
for (i = 0; i < host->n_ports; i++) {
struct ata_port *ap = host->ports[i];
if (polling & (1 << i))
continue;
if (!ap->ops->sff_irq_check ||
!ap->ops->sff_irq_check(ap))
continue;
if (idle & (1 << i)) {
ap->ops->sff_check_status(ap);
if (ap->ops->sff_irq_clear)
ap->ops->sff_irq_clear(ap);
} else {
/* clear INTRQ and check if BUSY cleared */
if (!(ap->ops->sff_check_status(ap) & ATA_BUSY))
retry |= true;
/*
* With command in flight, we can't do
* sff_irq_clear() w/o racing with completion.
*/
}
}
if (retry) {
retried = true;
goto retry;
}
}
spin_unlock_irqrestore(&host->lock, flags);
return IRQ_RETVAL(handled);
}
/**
* ata_sff_interrupt - Default SFF ATA host interrupt handler
* @irq: irq line (unused)
* @dev_instance: pointer to our ata_host information structure
*
* Default interrupt handler for PCI IDE devices. Calls
* ata_sff_port_intr() for each port that is not disabled.
*
* LOCKING:
* Obtains host lock during operation.
*
* RETURNS:
* IRQ_NONE or IRQ_HANDLED.
*/
irqreturn_t ata_sff_interrupt(int irq, void *dev_instance)
{
return __ata_sff_interrupt(irq, dev_instance, ata_sff_port_intr);
}
EXPORT_SYMBOL_GPL(ata_sff_interrupt);
/**
* ata_sff_lost_interrupt - Check for an apparent lost interrupt
* @ap: port that appears to have timed out
*
* Called from the libata error handlers when the core code suspects
* an interrupt has been lost. If it has complete anything we can and
* then return. Interface must support altstatus for this faster
* recovery to occur.
*
* Locking:
* Caller holds host lock
*/
void ata_sff_lost_interrupt(struct ata_port *ap)
{
u8 status = 0;
struct ata_queued_cmd *qc;
/* Only one outstanding command per SFF channel */
qc = ata_qc_from_tag(ap, ap->link.active_tag);
/* We cannot lose an interrupt on a non-existent or polled command */
if (!qc || qc->tf.flags & ATA_TFLAG_POLLING)
return;
/* See if the controller thinks it is still busy - if so the command
isn't a lost IRQ but is still in progress */
if (WARN_ON_ONCE(!ata_sff_altstatus(ap, &status)))
return;
if (status & ATA_BUSY)
return;
/* There was a command running, we are no longer busy and we have
no interrupt. */
ata_port_warn(ap, "lost interrupt (Status 0x%x)\n", status);
/* Run the host interrupt logic as if the interrupt had not been
lost */
ata_sff_port_intr(ap, qc);
}
EXPORT_SYMBOL_GPL(ata_sff_lost_interrupt);
/**
* ata_sff_freeze - Freeze SFF controller port
* @ap: port to freeze
*
* Freeze SFF controller port.
*
* LOCKING:
* Inherited from caller.
*/
void ata_sff_freeze(struct ata_port *ap)
{
ap->ctl |= ATA_NIEN;
ap->last_ctl = ap->ctl;
ata_sff_set_devctl(ap, ap->ctl);
/* Under certain circumstances, some controllers raise IRQ on
* ATA_NIEN manipulation. Also, many controllers fail to mask
* previously pending IRQ on ATA_NIEN assertion. Clear it.
*/
ap->ops->sff_check_status(ap);
if (ap->ops->sff_irq_clear)
ap->ops->sff_irq_clear(ap);
}
EXPORT_SYMBOL_GPL(ata_sff_freeze);
/**
* ata_sff_thaw - Thaw SFF controller port
* @ap: port to thaw
*
* Thaw SFF controller port.
*
* LOCKING:
* Inherited from caller.
*/
void ata_sff_thaw(struct ata_port *ap)
{
/* clear & re-enable interrupts */
ap->ops->sff_check_status(ap);
if (ap->ops->sff_irq_clear)
ap->ops->sff_irq_clear(ap);
ata_sff_irq_on(ap);
}
EXPORT_SYMBOL_GPL(ata_sff_thaw);
/**
* ata_sff_prereset - prepare SFF link for reset
* @link: SFF link to be reset
* @deadline: deadline jiffies for the operation
*
* SFF link @link is about to be reset. Initialize it. It first
* calls ata_std_prereset() and wait for !BSY if the port is
* being softreset.
*
* LOCKING:
* Kernel thread context (may sleep)
*
* RETURNS:
* Always 0.
*/
int ata_sff_prereset(struct ata_link *link, unsigned long deadline)
{
struct ata_eh_context *ehc = &link->eh_context;
int rc;
/* The standard prereset is best-effort and always returns 0 */
ata_std_prereset(link, deadline);
/* if we're about to do hardreset, nothing more to do */
if (ehc->i.action & ATA_EH_HARDRESET)
return 0;
/* wait for !BSY if we don't know that no device is attached */
if (!ata_link_offline(link)) {
rc = ata_sff_wait_ready(link, deadline);
if (rc && rc != -ENODEV) {
ata_link_warn(link,
"device not ready (errno=%d), forcing hardreset\n",
rc);
ehc->i.action |= ATA_EH_HARDRESET;
}
}
return 0;
}
EXPORT_SYMBOL_GPL(ata_sff_prereset);
/**
* ata_devchk - PATA device presence detection
* @ap: ATA channel to examine
* @device: Device to examine (starting at zero)
*
* This technique was originally described in
* Hale Landis's ATADRVR (www.ata-atapi.com), and
* later found its way into the ATA/ATAPI spec.
*
* Write a pattern to the ATA shadow registers,
* and if a device is present, it will respond by
* correctly storing and echoing back the
* ATA shadow register contents.
*
* RETURN:
* true if device is present, false if not.
*
* LOCKING:
* caller.
*/
static bool ata_devchk(struct ata_port *ap, unsigned int device)
{
struct ata_ioports *ioaddr = &ap->ioaddr;
u8 nsect, lbal;
ap->ops->sff_dev_select(ap, device);
iowrite8(0x55, ioaddr->nsect_addr);
iowrite8(0xaa, ioaddr->lbal_addr);
iowrite8(0xaa, ioaddr->nsect_addr);
iowrite8(0x55, ioaddr->lbal_addr);
iowrite8(0x55, ioaddr->nsect_addr);
iowrite8(0xaa, ioaddr->lbal_addr);
nsect = ioread8(ioaddr->nsect_addr);
lbal = ioread8(ioaddr->lbal_addr);
if ((nsect == 0x55) && (lbal == 0xaa))
return true; /* we found a device */
return false; /* nothing found */
}
/**
* ata_sff_dev_classify - Parse returned ATA device signature
* @dev: ATA device to classify (starting at zero)
* @present: device seems present
* @r_err: Value of error register on completion
*
* After an event -- SRST, E.D.D., or SATA COMRESET -- occurs,
* an ATA/ATAPI-defined set of values is placed in the ATA
* shadow registers, indicating the results of device detection
* and diagnostics.
*
* Select the ATA device, and read the values from the ATA shadow
* registers. Then parse according to the Error register value,
* and the spec-defined values examined by ata_dev_classify().
*
* LOCKING:
* caller.
*
* RETURNS:
* Device type - %ATA_DEV_ATA, %ATA_DEV_ATAPI or %ATA_DEV_NONE.
*/
unsigned int ata_sff_dev_classify(struct ata_device *dev, int present,
u8 *r_err)
{
struct ata_port *ap = dev->link->ap;
struct ata_taskfile tf;
unsigned int class;
u8 err;
ap->ops->sff_dev_select(ap, dev->devno);
memset(&tf, 0, sizeof(tf));
ap->ops->sff_tf_read(ap, &tf);
err = tf.error;
if (r_err)
*r_err = err;
/* see if device passed diags: continue and warn later */
if (err == 0)
/* diagnostic fail : do nothing _YET_ */
dev->horkage |= ATA_HORKAGE_DIAGNOSTIC;
else if (err == 1)
/* do nothing */ ;
else if ((dev->devno == 0) && (err == 0x81))
/* do nothing */ ;
else
return ATA_DEV_NONE;
/* determine if device is ATA or ATAPI */
class = ata_port_classify(ap, &tf);
switch (class) {
case ATA_DEV_UNKNOWN:
/*
* If the device failed diagnostic, it's likely to
* have reported incorrect device signature too.
* Assume ATA device if the device seems present but
* device signature is invalid with diagnostic
* failure.
*/
if (present && (dev->horkage & ATA_HORKAGE_DIAGNOSTIC))
class = ATA_DEV_ATA;
else
class = ATA_DEV_NONE;
break;
case ATA_DEV_ATA:
if (ap->ops->sff_check_status(ap) == 0)
class = ATA_DEV_NONE;
break;
}
return class;
}
EXPORT_SYMBOL_GPL(ata_sff_dev_classify);
/**
* ata_sff_wait_after_reset - wait for devices to become ready after reset
* @link: SFF link which is just reset
* @devmask: mask of present devices
* @deadline: deadline jiffies for the operation
*
* Wait devices attached to SFF @link to become ready after
* reset. It contains preceding 150ms wait to avoid accessing TF
* status register too early.
*
* LOCKING:
* Kernel thread context (may sleep).
*
* RETURNS:
* 0 on success, -ENODEV if some or all of devices in @devmask
* don't seem to exist. -errno on other errors.
*/
int ata_sff_wait_after_reset(struct ata_link *link, unsigned int devmask,
unsigned long deadline)
{
struct ata_port *ap = link->ap;
struct ata_ioports *ioaddr = &ap->ioaddr;
unsigned int dev0 = devmask & (1 << 0);
unsigned int dev1 = devmask & (1 << 1);
int rc, ret = 0;
ata_msleep(ap, ATA_WAIT_AFTER_RESET);
/* always check readiness of the master device */
rc = ata_sff_wait_ready(link, deadline);
/* -ENODEV means the odd clown forgot the D7 pulldown resistor
* and TF status is 0xff, bail out on it too.
*/
if (rc)
return rc;
/* if device 1 was found in ata_devchk, wait for register
* access briefly, then wait for BSY to clear.
*/
if (dev1) {
int i;
ap->ops->sff_dev_select(ap, 1);
/* Wait for register access. Some ATAPI devices fail
* to set nsect/lbal after reset, so don't waste too
* much time on it. We're gonna wait for !BSY anyway.
*/
for (i = 0; i < 2; i++) {
u8 nsect, lbal;
nsect = ioread8(ioaddr->nsect_addr);
lbal = ioread8(ioaddr->lbal_addr);
if ((nsect == 1) && (lbal == 1))
break;
ata_msleep(ap, 50); /* give drive a breather */
}
rc = ata_sff_wait_ready(link, deadline);
if (rc) {
if (rc != -ENODEV)
return rc;
ret = rc;
}
}
/* is all this really necessary? */
ap->ops->sff_dev_select(ap, 0);
if (dev1)
ap->ops->sff_dev_select(ap, 1);
if (dev0)
ap->ops->sff_dev_select(ap, 0);
return ret;
}
EXPORT_SYMBOL_GPL(ata_sff_wait_after_reset);
static int ata_bus_softreset(struct ata_port *ap, unsigned int devmask,
unsigned long deadline)
{
struct ata_ioports *ioaddr = &ap->ioaddr;
if (ap->ioaddr.ctl_addr) {
/* software reset. causes dev0 to be selected */
iowrite8(ap->ctl, ioaddr->ctl_addr);
udelay(20); /* FIXME: flush */
iowrite8(ap->ctl | ATA_SRST, ioaddr->ctl_addr);
udelay(20); /* FIXME: flush */
iowrite8(ap->ctl, ioaddr->ctl_addr);
ap->last_ctl = ap->ctl;
}
/* wait the port to become ready */
return ata_sff_wait_after_reset(&ap->link, devmask, deadline);
}
/**
* ata_sff_softreset - reset host port via ATA SRST
* @link: ATA link to reset
* @classes: resulting classes of attached devices
* @deadline: deadline jiffies for the operation
*
* Reset host port using ATA SRST.
*
* LOCKING:
* Kernel thread context (may sleep)
*
* RETURNS:
* 0 on success, -errno otherwise.
*/
int ata_sff_softreset(struct ata_link *link, unsigned int *classes,
unsigned long deadline)
{
struct ata_port *ap = link->ap;
unsigned int slave_possible = ap->flags & ATA_FLAG_SLAVE_POSS;
unsigned int devmask = 0;
int rc;
u8 err;
/* determine if device 0/1 are present */
if (ata_devchk(ap, 0))
devmask |= (1 << 0);
if (slave_possible && ata_devchk(ap, 1))
devmask |= (1 << 1);
/* select device 0 again */
ap->ops->sff_dev_select(ap, 0);
/* issue bus reset */
rc = ata_bus_softreset(ap, devmask, deadline);
/* if link is occupied, -ENODEV too is an error */
if (rc && (rc != -ENODEV || sata_scr_valid(link))) {
ata_link_err(link, "SRST failed (errno=%d)\n", rc);
return rc;
}
/* determine by signature whether we have ATA or ATAPI devices */
classes[0] = ata_sff_dev_classify(&link->device[0],
devmask & (1 << 0), &err);
if (slave_possible && err != 0x81)
classes[1] = ata_sff_dev_classify(&link->device[1],
devmask & (1 << 1), &err);
return 0;
}
EXPORT_SYMBOL_GPL(ata_sff_softreset);
/**
* sata_sff_hardreset - reset host port via SATA phy reset
* @link: link to reset
* @class: resulting class of attached device
* @deadline: deadline jiffies for the operation
*
* SATA phy-reset host port using DET bits of SControl register,
* wait for !BSY and classify the attached device.
*
* LOCKING:
* Kernel thread context (may sleep)
*
* RETURNS:
* 0 on success, -errno otherwise.
*/
int sata_sff_hardreset(struct ata_link *link, unsigned int *class,
unsigned long deadline)
{
struct ata_eh_context *ehc = &link->eh_context;
const unsigned int *timing = sata_ehc_deb_timing(ehc);
bool online;
int rc;
rc = sata_link_hardreset(link, timing, deadline, &online,
ata_sff_check_ready);
if (online)
*class = ata_sff_dev_classify(link->device, 1, NULL);
return rc;
}
EXPORT_SYMBOL_GPL(sata_sff_hardreset);
/**
* ata_sff_postreset - SFF postreset callback
* @link: the target SFF ata_link
* @classes: classes of attached devices
*
* This function is invoked after a successful reset. It first
* calls ata_std_postreset() and performs SFF specific postreset
* processing.
*
* LOCKING:
* Kernel thread context (may sleep)
*/
void ata_sff_postreset(struct ata_link *link, unsigned int *classes)
{
struct ata_port *ap = link->ap;
ata_std_postreset(link, classes);
/* is double-select really necessary? */
if (classes[0] != ATA_DEV_NONE)
ap->ops->sff_dev_select(ap, 1);
if (classes[1] != ATA_DEV_NONE)
ap->ops->sff_dev_select(ap, 0);
/* bail out if no device is present */
if (classes[0] == ATA_DEV_NONE && classes[1] == ATA_DEV_NONE)
return;
/* set up device control */
if (ata_sff_set_devctl(ap, ap->ctl))
ap->last_ctl = ap->ctl;
}
EXPORT_SYMBOL_GPL(ata_sff_postreset);
/**
* ata_sff_drain_fifo - Stock FIFO drain logic for SFF controllers
* @qc: command
*
* Drain the FIFO and device of any stuck data following a command
* failing to complete. In some cases this is necessary before a
* reset will recover the device.
*
*/
void ata_sff_drain_fifo(struct ata_queued_cmd *qc)
{
int count;
struct ata_port *ap;
/* We only need to flush incoming data when a command was running */
if (qc == NULL || qc->dma_dir == DMA_TO_DEVICE)
return;
ap = qc->ap;
/* Drain up to 64K of data before we give up this recovery method */
for (count = 0; (ap->ops->sff_check_status(ap) & ATA_DRQ)
&& count < 65536; count += 2)
ioread16(ap->ioaddr.data_addr);
if (count)
ata_port_dbg(ap, "drained %d bytes to clear DRQ\n", count);
}
EXPORT_SYMBOL_GPL(ata_sff_drain_fifo);
/**
* ata_sff_error_handler - Stock error handler for SFF controller
* @ap: port to handle error for
*
* Stock error handler for SFF controller. It can handle both
* PATA and SATA controllers. Many controllers should be able to
* use this EH as-is or with some added handling before and
* after.
*
* LOCKING:
* Kernel thread context (may sleep)
*/
void ata_sff_error_handler(struct ata_port *ap)
{
ata_reset_fn_t softreset = ap->ops->softreset;
ata_reset_fn_t hardreset = ap->ops->hardreset;
struct ata_queued_cmd *qc;
unsigned long flags;
qc = __ata_qc_from_tag(ap, ap->link.active_tag);
if (qc && !(qc->flags & ATA_QCFLAG_EH))
qc = NULL;
spin_lock_irqsave(ap->lock, flags);
/*
* We *MUST* do FIFO draining before we issue a reset as
* several devices helpfully clear their internal state and
* will lock solid if we touch the data port post reset. Pass
* qc in case anyone wants to do different PIO/DMA recovery or
* has per command fixups
*/
if (ap->ops->sff_drain_fifo)
ap->ops->sff_drain_fifo(qc);
spin_unlock_irqrestore(ap->lock, flags);
/* ignore built-in hardresets if SCR access is not available */
if ((hardreset == sata_std_hardreset ||
hardreset == sata_sff_hardreset) && !sata_scr_valid(&ap->link))
hardreset = NULL;
ata_do_eh(ap, ap->ops->prereset, softreset, hardreset,
ap->ops->postreset);
}
EXPORT_SYMBOL_GPL(ata_sff_error_handler);
/**
* ata_sff_std_ports - initialize ioaddr with standard port offsets.
* @ioaddr: IO address structure to be initialized
*
* Utility function which initializes data_addr, error_addr,
* feature_addr, nsect_addr, lbal_addr, lbam_addr, lbah_addr,
* device_addr, status_addr, and command_addr to standard offsets
* relative to cmd_addr.
*
* Does not set ctl_addr, altstatus_addr, bmdma_addr, or scr_addr.
*/
void ata_sff_std_ports(struct ata_ioports *ioaddr)
{
ioaddr->data_addr = ioaddr->cmd_addr + ATA_REG_DATA;
ioaddr->error_addr = ioaddr->cmd_addr + ATA_REG_ERR;
ioaddr->feature_addr = ioaddr->cmd_addr + ATA_REG_FEATURE;
ioaddr->nsect_addr = ioaddr->cmd_addr + ATA_REG_NSECT;
ioaddr->lbal_addr = ioaddr->cmd_addr + ATA_REG_LBAL;
ioaddr->lbam_addr = ioaddr->cmd_addr + ATA_REG_LBAM;
ioaddr->lbah_addr = ioaddr->cmd_addr + ATA_REG_LBAH;
ioaddr->device_addr = ioaddr->cmd_addr + ATA_REG_DEVICE;
ioaddr->status_addr = ioaddr->cmd_addr + ATA_REG_STATUS;
ioaddr->command_addr = ioaddr->cmd_addr + ATA_REG_CMD;
}
EXPORT_SYMBOL_GPL(ata_sff_std_ports);
#ifdef CONFIG_PCI
static bool ata_resources_present(struct pci_dev *pdev, int port)
{
int i;
/* Check the PCI resources for this channel are enabled */
port *= 2;
for (i = 0; i < 2; i++) {
if (pci_resource_start(pdev, port + i) == 0 ||
pci_resource_len(pdev, port + i) == 0)
return false;
}
return true;
}
/**
* ata_pci_sff_init_host - acquire native PCI ATA resources and init host
* @host: target ATA host
*
* Acquire native PCI ATA resources for @host and initialize the
* first two ports of @host accordingly. Ports marked dummy are
* skipped and allocation failure makes the port dummy.
*
* Note that native PCI resources are valid even for legacy hosts
* as we fix up pdev resources array early in boot, so this
* function can be used for both native and legacy SFF hosts.
*
* LOCKING:
* Inherited from calling layer (may sleep).
*
* RETURNS:
* 0 if at least one port is initialized, -ENODEV if no port is
* available.
*/
int ata_pci_sff_init_host(struct ata_host *host)
{
struct device *gdev = host->dev;
struct pci_dev *pdev = to_pci_dev(gdev);
unsigned int mask = 0;
int i, rc;
/* request, iomap BARs and init port addresses accordingly */
for (i = 0; i < 2; i++) {
struct ata_port *ap = host->ports[i];
int base = i * 2;
void __iomem * const *iomap;
if (ata_port_is_dummy(ap))
continue;
/* Discard disabled ports. Some controllers show
* their unused channels this way. Disabled ports are
* made dummy.
*/
if (!ata_resources_present(pdev, i)) {
ap->ops = &ata_dummy_port_ops;
continue;
}
rc = pcim_iomap_regions(pdev, 0x3 << base,
dev_driver_string(gdev));
if (rc) {
dev_warn(gdev,
"failed to request/iomap BARs for port %d (errno=%d)\n",
i, rc);
if (rc == -EBUSY)
pcim_pin_device(pdev);
ap->ops = &ata_dummy_port_ops;
continue;
}
host->iomap = iomap = pcim_iomap_table(pdev);
ap->ioaddr.cmd_addr = iomap[base];
ap->ioaddr.altstatus_addr =
ap->ioaddr.ctl_addr = (void __iomem *)
((unsigned long)iomap[base + 1] | ATA_PCI_CTL_OFS);
ata_sff_std_ports(&ap->ioaddr);
ata_port_desc(ap, "cmd 0x%llx ctl 0x%llx",
(unsigned long long)pci_resource_start(pdev, base),
(unsigned long long)pci_resource_start(pdev, base + 1));
mask |= 1 << i;
}
if (!mask) {
dev_err(gdev, "no available native port\n");
return -ENODEV;
}
return 0;
}
EXPORT_SYMBOL_GPL(ata_pci_sff_init_host);
/**
* ata_pci_sff_prepare_host - helper to prepare PCI PIO-only SFF ATA host
* @pdev: target PCI device
* @ppi: array of port_info, must be enough for two ports
* @r_host: out argument for the initialized ATA host
*
* Helper to allocate PIO-only SFF ATA host for @pdev, acquire
* all PCI resources and initialize it accordingly in one go.
*
* LOCKING:
* Inherited from calling layer (may sleep).
*
* RETURNS:
* 0 on success, -errno otherwise.
*/
int ata_pci_sff_prepare_host(struct pci_dev *pdev,
const struct ata_port_info * const *ppi,
struct ata_host **r_host)
{
struct ata_host *host;
int rc;
if (!devres_open_group(&pdev->dev, NULL, GFP_KERNEL))
return -ENOMEM;
host = ata_host_alloc_pinfo(&pdev->dev, ppi, 2);
if (!host) {
dev_err(&pdev->dev, "failed to allocate ATA host\n");
rc = -ENOMEM;
goto err_out;
}
rc = ata_pci_sff_init_host(host);
if (rc)
goto err_out;
devres_remove_group(&pdev->dev, NULL);
*r_host = host;
return 0;
err_out:
devres_release_group(&pdev->dev, NULL);
return rc;
}
EXPORT_SYMBOL_GPL(ata_pci_sff_prepare_host);
/**
* ata_pci_sff_activate_host - start SFF host, request IRQ and register it
* @host: target SFF ATA host
* @irq_handler: irq_handler used when requesting IRQ(s)
* @sht: scsi_host_template to use when registering the host
*
* This is the counterpart of ata_host_activate() for SFF ATA
* hosts. This separate helper is necessary because SFF hosts
* use two separate interrupts in legacy mode.
*
* LOCKING:
* Inherited from calling layer (may sleep).
*
* RETURNS:
* 0 on success, -errno otherwise.
*/
int ata_pci_sff_activate_host(struct ata_host *host,
irq_handler_t irq_handler,
struct scsi_host_template *sht)
{
struct device *dev = host->dev;
struct pci_dev *pdev = to_pci_dev(dev);
const char *drv_name = dev_driver_string(host->dev);
int legacy_mode = 0, rc;
rc = ata_host_start(host);
if (rc)
return rc;
if ((pdev->class >> 8) == PCI_CLASS_STORAGE_IDE) {
u8 tmp8, mask = 0;
/*
* ATA spec says we should use legacy mode when one
* port is in legacy mode, but disabled ports on some
* PCI hosts appear as fixed legacy ports, e.g SB600/700
* on which the secondary port is not wired, so
* ignore ports that are marked as 'dummy' during
* this check
*/
pci_read_config_byte(pdev, PCI_CLASS_PROG, &tmp8);
if (!ata_port_is_dummy(host->ports[0]))
mask |= (1 << 0);
if (!ata_port_is_dummy(host->ports[1]))
mask |= (1 << 2);
if ((tmp8 & mask) != mask)
legacy_mode = 1;
}
if (!devres_open_group(dev, NULL, GFP_KERNEL))
return -ENOMEM;
if (!legacy_mode && pdev->irq) {
int i;
rc = devm_request_irq(dev, pdev->irq, irq_handler,
IRQF_SHARED, drv_name, host);
if (rc)
goto out;
for (i = 0; i < 2; i++) {
if (ata_port_is_dummy(host->ports[i]))
continue;
ata_port_desc_misc(host->ports[i], pdev->irq);
}
} else if (legacy_mode) {
if (!ata_port_is_dummy(host->ports[0])) {
rc = devm_request_irq(dev, ATA_PRIMARY_IRQ(pdev),
irq_handler, IRQF_SHARED,
drv_name, host);
if (rc)
goto out;
ata_port_desc_misc(host->ports[0],
ATA_PRIMARY_IRQ(pdev));
}
if (!ata_port_is_dummy(host->ports[1])) {
rc = devm_request_irq(dev, ATA_SECONDARY_IRQ(pdev),
irq_handler, IRQF_SHARED,
drv_name, host);
if (rc)
goto out;
ata_port_desc_misc(host->ports[1],
ATA_SECONDARY_IRQ(pdev));
}
}
rc = ata_host_register(host, sht);
out:
if (rc == 0)
devres_remove_group(dev, NULL);
else
devres_release_group(dev, NULL);
return rc;
}
EXPORT_SYMBOL_GPL(ata_pci_sff_activate_host);
static const struct ata_port_info *ata_sff_find_valid_pi(
const struct ata_port_info * const *ppi)
{
int i;
/* look up the first valid port_info */
for (i = 0; i < 2 && ppi[i]; i++)
if (ppi[i]->port_ops != &ata_dummy_port_ops)
return ppi[i];
return NULL;
}
static int ata_pci_init_one(struct pci_dev *pdev,
const struct ata_port_info * const *ppi,
struct scsi_host_template *sht, void *host_priv,
int hflags, bool bmdma)
{
struct device *dev = &pdev->dev;
const struct ata_port_info *pi;
struct ata_host *host = NULL;
int rc;
pi = ata_sff_find_valid_pi(ppi);
if (!pi) {
dev_err(&pdev->dev, "no valid port_info specified\n");
return -EINVAL;
}
if (!devres_open_group(dev, NULL, GFP_KERNEL))
return -ENOMEM;
rc = pcim_enable_device(pdev);
if (rc)
goto out;
#ifdef CONFIG_ATA_BMDMA
if (bmdma)
/* prepare and activate BMDMA host */
rc = ata_pci_bmdma_prepare_host(pdev, ppi, &host);
else
#endif
/* prepare and activate SFF host */
rc = ata_pci_sff_prepare_host(pdev, ppi, &host);
if (rc)
goto out;
host->private_data = host_priv;
host->flags |= hflags;
#ifdef CONFIG_ATA_BMDMA
if (bmdma) {
pci_set_master(pdev);
rc = ata_pci_sff_activate_host(host, ata_bmdma_interrupt, sht);
} else
#endif
rc = ata_pci_sff_activate_host(host, ata_sff_interrupt, sht);
out:
if (rc == 0)
devres_remove_group(&pdev->dev, NULL);
else
devres_release_group(&pdev->dev, NULL);
return rc;
}
/**
* ata_pci_sff_init_one - Initialize/register PIO-only PCI IDE controller
* @pdev: Controller to be initialized
* @ppi: array of port_info, must be enough for two ports
* @sht: scsi_host_template to use when registering the host
* @host_priv: host private_data
* @hflag: host flags
*
* This is a helper function which can be called from a driver's
* xxx_init_one() probe function if the hardware uses traditional
* IDE taskfile registers and is PIO only.
*
* ASSUMPTION:
* Nobody makes a single channel controller that appears solely as
* the secondary legacy port on PCI.
*
* LOCKING:
* Inherited from PCI layer (may sleep).
*
* RETURNS:
* Zero on success, negative on errno-based value on error.
*/
int ata_pci_sff_init_one(struct pci_dev *pdev,
const struct ata_port_info * const *ppi,
struct scsi_host_template *sht, void *host_priv, int hflag)
{
return ata_pci_init_one(pdev, ppi, sht, host_priv, hflag, 0);
}
EXPORT_SYMBOL_GPL(ata_pci_sff_init_one);
#endif /* CONFIG_PCI */
/*
* BMDMA support
*/
#ifdef CONFIG_ATA_BMDMA
const struct ata_port_operations ata_bmdma_port_ops = {
.inherits = &ata_sff_port_ops,
.error_handler = ata_bmdma_error_handler,
.post_internal_cmd = ata_bmdma_post_internal_cmd,
.qc_prep = ata_bmdma_qc_prep,
.qc_issue = ata_bmdma_qc_issue,
.sff_irq_clear = ata_bmdma_irq_clear,
.bmdma_setup = ata_bmdma_setup,
.bmdma_start = ata_bmdma_start,
.bmdma_stop = ata_bmdma_stop,
.bmdma_status = ata_bmdma_status,
.port_start = ata_bmdma_port_start,
};
EXPORT_SYMBOL_GPL(ata_bmdma_port_ops);
const struct ata_port_operations ata_bmdma32_port_ops = {
.inherits = &ata_bmdma_port_ops,
.sff_data_xfer = ata_sff_data_xfer32,
.port_start = ata_bmdma_port_start32,
};
EXPORT_SYMBOL_GPL(ata_bmdma32_port_ops);
/**
* ata_bmdma_fill_sg - Fill PCI IDE PRD table
* @qc: Metadata associated with taskfile to be transferred
*
* Fill PCI IDE PRD (scatter-gather) table with segments
* associated with the current disk command.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*
*/
static void ata_bmdma_fill_sg(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
struct ata_bmdma_prd *prd = ap->bmdma_prd;
struct scatterlist *sg;
unsigned int si, pi;
pi = 0;
for_each_sg(qc->sg, sg, qc->n_elem, si) {
u32 addr, offset;
u32 sg_len, len;
/* determine if physical DMA addr spans 64K boundary.
* Note h/w doesn't support 64-bit, so we unconditionally
* truncate dma_addr_t to u32.
*/
addr = (u32) sg_dma_address(sg);
sg_len = sg_dma_len(sg);
while (sg_len) {
offset = addr & 0xffff;
len = sg_len;
if ((offset + sg_len) > 0x10000)
len = 0x10000 - offset;
prd[pi].addr = cpu_to_le32(addr);
prd[pi].flags_len = cpu_to_le32(len & 0xffff);
pi++;
sg_len -= len;
addr += len;
}
}
prd[pi - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
}
/**
* ata_bmdma_fill_sg_dumb - Fill PCI IDE PRD table
* @qc: Metadata associated with taskfile to be transferred
*
* Fill PCI IDE PRD (scatter-gather) table with segments
* associated with the current disk command. Perform the fill
* so that we avoid writing any length 64K records for
* controllers that don't follow the spec.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*
*/
static void ata_bmdma_fill_sg_dumb(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
struct ata_bmdma_prd *prd = ap->bmdma_prd;
struct scatterlist *sg;
unsigned int si, pi;
pi = 0;
for_each_sg(qc->sg, sg, qc->n_elem, si) {
u32 addr, offset;
u32 sg_len, len, blen;
/* determine if physical DMA addr spans 64K boundary.
* Note h/w doesn't support 64-bit, so we unconditionally
* truncate dma_addr_t to u32.
*/
addr = (u32) sg_dma_address(sg);
sg_len = sg_dma_len(sg);
while (sg_len) {
offset = addr & 0xffff;
len = sg_len;
if ((offset + sg_len) > 0x10000)
len = 0x10000 - offset;
blen = len & 0xffff;
prd[pi].addr = cpu_to_le32(addr);
if (blen == 0) {
/* Some PATA chipsets like the CS5530 can't
cope with 0x0000 meaning 64K as the spec
says */
prd[pi].flags_len = cpu_to_le32(0x8000);
blen = 0x8000;
prd[++pi].addr = cpu_to_le32(addr + 0x8000);
}
prd[pi].flags_len = cpu_to_le32(blen);
pi++;
sg_len -= len;
addr += len;
}
}
prd[pi - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
}
/**
* ata_bmdma_qc_prep - Prepare taskfile for submission
* @qc: Metadata associated with taskfile to be prepared
*
* Prepare ATA taskfile for submission.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
enum ata_completion_errors ata_bmdma_qc_prep(struct ata_queued_cmd *qc)
{
if (!(qc->flags & ATA_QCFLAG_DMAMAP))
return AC_ERR_OK;
ata_bmdma_fill_sg(qc);
return AC_ERR_OK;
}
EXPORT_SYMBOL_GPL(ata_bmdma_qc_prep);
/**
* ata_bmdma_dumb_qc_prep - Prepare taskfile for submission
* @qc: Metadata associated with taskfile to be prepared
*
* Prepare ATA taskfile for submission.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
enum ata_completion_errors ata_bmdma_dumb_qc_prep(struct ata_queued_cmd *qc)
{
if (!(qc->flags & ATA_QCFLAG_DMAMAP))
return AC_ERR_OK;
ata_bmdma_fill_sg_dumb(qc);
return AC_ERR_OK;
}
EXPORT_SYMBOL_GPL(ata_bmdma_dumb_qc_prep);
/**
* ata_bmdma_qc_issue - issue taskfile to a BMDMA controller
* @qc: command to issue to device
*
* This function issues a PIO, NODATA or DMA command to a
* SFF/BMDMA controller. PIO and NODATA are handled by
* ata_sff_qc_issue().
*
* LOCKING:
* spin_lock_irqsave(host lock)
*
* RETURNS:
* Zero on success, AC_ERR_* mask on failure
*/
unsigned int ata_bmdma_qc_issue(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
struct ata_link *link = qc->dev->link;
/* defer PIO handling to sff_qc_issue */
if (!ata_is_dma(qc->tf.protocol))
return ata_sff_qc_issue(qc);
/* select the device */
ata_dev_select(ap, qc->dev->devno, 1, 0);
/* start the command */
switch (qc->tf.protocol) {
case ATA_PROT_DMA:
WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
trace_ata_tf_load(ap, &qc->tf);
ap->ops->sff_tf_load(ap, &qc->tf); /* load tf registers */
trace_ata_bmdma_setup(ap, &qc->tf, qc->tag);
ap->ops->bmdma_setup(qc); /* set up bmdma */
trace_ata_bmdma_start(ap, &qc->tf, qc->tag);
ap->ops->bmdma_start(qc); /* initiate bmdma */
ap->hsm_task_state = HSM_ST_LAST;
break;
case ATAPI_PROT_DMA:
WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
trace_ata_tf_load(ap, &qc->tf);
ap->ops->sff_tf_load(ap, &qc->tf); /* load tf registers */
trace_ata_bmdma_setup(ap, &qc->tf, qc->tag);
ap->ops->bmdma_setup(qc); /* set up bmdma */
ap->hsm_task_state = HSM_ST_FIRST;
/* send cdb by polling if no cdb interrupt */
if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
ata_sff_queue_pio_task(link, 0);
break;
default:
WARN_ON(1);
return AC_ERR_SYSTEM;
}
return 0;
}
EXPORT_SYMBOL_GPL(ata_bmdma_qc_issue);
/**
* ata_bmdma_port_intr - Handle BMDMA port interrupt
* @ap: Port on which interrupt arrived (possibly...)
* @qc: Taskfile currently active in engine
*
* Handle port interrupt for given queued command.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*
* RETURNS:
* One if interrupt was handled, zero if not (shared irq).
*/
unsigned int ata_bmdma_port_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
{
struct ata_eh_info *ehi = &ap->link.eh_info;
u8 host_stat = 0;
bool bmdma_stopped = false;
unsigned int handled;
if (ap->hsm_task_state == HSM_ST_LAST && ata_is_dma(qc->tf.protocol)) {
/* check status of DMA engine */
host_stat = ap->ops->bmdma_status(ap);
trace_ata_bmdma_status(ap, host_stat);
/* if it's not our irq... */
if (!(host_stat & ATA_DMA_INTR))
return ata_sff_idle_irq(ap);
/* before we do anything else, clear DMA-Start bit */
trace_ata_bmdma_stop(ap, &qc->tf, qc->tag);
ap->ops->bmdma_stop(qc);
bmdma_stopped = true;
if (unlikely(host_stat & ATA_DMA_ERR)) {
/* error when transferring data to/from memory */
qc->err_mask |= AC_ERR_HOST_BUS;
ap->hsm_task_state = HSM_ST_ERR;
}
}
handled = __ata_sff_port_intr(ap, qc, bmdma_stopped);
if (unlikely(qc->err_mask) && ata_is_dma(qc->tf.protocol))
ata_ehi_push_desc(ehi, "BMDMA stat 0x%x", host_stat);
return handled;
}
EXPORT_SYMBOL_GPL(ata_bmdma_port_intr);
/**
* ata_bmdma_interrupt - Default BMDMA ATA host interrupt handler
* @irq: irq line (unused)
* @dev_instance: pointer to our ata_host information structure
*
* Default interrupt handler for PCI IDE devices. Calls
* ata_bmdma_port_intr() for each port that is not disabled.
*
* LOCKING:
* Obtains host lock during operation.
*
* RETURNS:
* IRQ_NONE or IRQ_HANDLED.
*/
irqreturn_t ata_bmdma_interrupt(int irq, void *dev_instance)
{
return __ata_sff_interrupt(irq, dev_instance, ata_bmdma_port_intr);
}
EXPORT_SYMBOL_GPL(ata_bmdma_interrupt);
/**
* ata_bmdma_error_handler - Stock error handler for BMDMA controller
* @ap: port to handle error for
*
* Stock error handler for BMDMA controller. It can handle both
* PATA and SATA controllers. Most BMDMA controllers should be
* able to use this EH as-is or with some added handling before
* and after.
*
* LOCKING:
* Kernel thread context (may sleep)
*/
void ata_bmdma_error_handler(struct ata_port *ap)
{
struct ata_queued_cmd *qc;
unsigned long flags;
bool thaw = false;
qc = __ata_qc_from_tag(ap, ap->link.active_tag);
if (qc && !(qc->flags & ATA_QCFLAG_EH))
qc = NULL;
/* reset PIO HSM and stop DMA engine */
spin_lock_irqsave(ap->lock, flags);
if (qc && ata_is_dma(qc->tf.protocol)) {
u8 host_stat;
host_stat = ap->ops->bmdma_status(ap);
trace_ata_bmdma_status(ap, host_stat);
/* BMDMA controllers indicate host bus error by
* setting DMA_ERR bit and timing out. As it wasn't
* really a timeout event, adjust error mask and
* cancel frozen state.
*/
if (qc->err_mask == AC_ERR_TIMEOUT && (host_stat & ATA_DMA_ERR)) {
qc->err_mask = AC_ERR_HOST_BUS;
thaw = true;
}
trace_ata_bmdma_stop(ap, &qc->tf, qc->tag);
ap->ops->bmdma_stop(qc);
/* if we're gonna thaw, make sure IRQ is clear */
if (thaw) {
ap->ops->sff_check_status(ap);
if (ap->ops->sff_irq_clear)
ap->ops->sff_irq_clear(ap);
}
}
spin_unlock_irqrestore(ap->lock, flags);
if (thaw)
ata_eh_thaw_port(ap);
ata_sff_error_handler(ap);
}
EXPORT_SYMBOL_GPL(ata_bmdma_error_handler);
/**
* ata_bmdma_post_internal_cmd - Stock post_internal_cmd for BMDMA
* @qc: internal command to clean up
*
* LOCKING:
* Kernel thread context (may sleep)
*/
void ata_bmdma_post_internal_cmd(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
unsigned long flags;
if (ata_is_dma(qc->tf.protocol)) {
spin_lock_irqsave(ap->lock, flags);
trace_ata_bmdma_stop(ap, &qc->tf, qc->tag);
ap->ops->bmdma_stop(qc);
spin_unlock_irqrestore(ap->lock, flags);
}
}
EXPORT_SYMBOL_GPL(ata_bmdma_post_internal_cmd);
/**
* ata_bmdma_irq_clear - Clear PCI IDE BMDMA interrupt.
* @ap: Port associated with this ATA transaction.
*
* Clear interrupt and error flags in DMA status register.
*
* May be used as the irq_clear() entry in ata_port_operations.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
void ata_bmdma_irq_clear(struct ata_port *ap)
{
void __iomem *mmio = ap->ioaddr.bmdma_addr;
if (!mmio)
return;
iowrite8(ioread8(mmio + ATA_DMA_STATUS), mmio + ATA_DMA_STATUS);
}
EXPORT_SYMBOL_GPL(ata_bmdma_irq_clear);
/**
* ata_bmdma_setup - Set up PCI IDE BMDMA transaction
* @qc: Info associated with this ATA transaction.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
void ata_bmdma_setup(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
unsigned int rw = (qc->tf.flags & ATA_TFLAG_WRITE);
u8 dmactl;
/* load PRD table addr. */
mb(); /* make sure PRD table writes are visible to controller */
iowrite32(ap->bmdma_prd_dma, ap->ioaddr.bmdma_addr + ATA_DMA_TABLE_OFS);
/* specify data direction, triple-check start bit is clear */
dmactl = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
dmactl &= ~(ATA_DMA_WR | ATA_DMA_START);
if (!rw)
dmactl |= ATA_DMA_WR;
iowrite8(dmactl, ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
/* issue r/w command */
ap->ops->sff_exec_command(ap, &qc->tf);
}
EXPORT_SYMBOL_GPL(ata_bmdma_setup);
/**
* ata_bmdma_start - Start a PCI IDE BMDMA transaction
* @qc: Info associated with this ATA transaction.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
void ata_bmdma_start(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
u8 dmactl;
/* start host DMA transaction */
dmactl = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
iowrite8(dmactl | ATA_DMA_START, ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
/* Strictly, one may wish to issue an ioread8() here, to
* flush the mmio write. However, control also passes
* to the hardware at this point, and it will interrupt
* us when we are to resume control. So, in effect,
* we don't care when the mmio write flushes.
* Further, a read of the DMA status register _immediately_
* following the write may not be what certain flaky hardware
* is expected, so I think it is best to not add a readb()
* without first all the MMIO ATA cards/mobos.
* Or maybe I'm just being paranoid.
*
* FIXME: The posting of this write means I/O starts are
* unnecessarily delayed for MMIO
*/
}
EXPORT_SYMBOL_GPL(ata_bmdma_start);
/**
* ata_bmdma_stop - Stop PCI IDE BMDMA transfer
* @qc: Command we are ending DMA for
*
* Clears the ATA_DMA_START flag in the dma control register
*
* May be used as the bmdma_stop() entry in ata_port_operations.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
void ata_bmdma_stop(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
void __iomem *mmio = ap->ioaddr.bmdma_addr;
/* clear start/stop bit */
iowrite8(ioread8(mmio + ATA_DMA_CMD) & ~ATA_DMA_START,
mmio + ATA_DMA_CMD);
/* one-PIO-cycle guaranteed wait, per spec, for HDMA1:0 transition */
ata_sff_dma_pause(ap);
}
EXPORT_SYMBOL_GPL(ata_bmdma_stop);
/**
* ata_bmdma_status - Read PCI IDE BMDMA status
* @ap: Port associated with this ATA transaction.
*
* Read and return BMDMA status register.
*
* May be used as the bmdma_status() entry in ata_port_operations.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
u8 ata_bmdma_status(struct ata_port *ap)
{
return ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
}
EXPORT_SYMBOL_GPL(ata_bmdma_status);
/**
* ata_bmdma_port_start - Set port up for bmdma.
* @ap: Port to initialize
*
* Called just after data structures for each port are
* initialized. Allocates space for PRD table.
*
* May be used as the port_start() entry in ata_port_operations.
*
* LOCKING:
* Inherited from caller.
*/
int ata_bmdma_port_start(struct ata_port *ap)
{
if (ap->mwdma_mask || ap->udma_mask) {
ap->bmdma_prd =
dmam_alloc_coherent(ap->host->dev, ATA_PRD_TBL_SZ,
&ap->bmdma_prd_dma, GFP_KERNEL);
if (!ap->bmdma_prd)
return -ENOMEM;
}
return 0;
}
EXPORT_SYMBOL_GPL(ata_bmdma_port_start);
/**
* ata_bmdma_port_start32 - Set port up for dma.
* @ap: Port to initialize
*
* Called just after data structures for each port are
* initialized. Enables 32bit PIO and allocates space for PRD
* table.
*
* May be used as the port_start() entry in ata_port_operations for
* devices that are capable of 32bit PIO.
*
* LOCKING:
* Inherited from caller.
*/
int ata_bmdma_port_start32(struct ata_port *ap)
{
ap->pflags |= ATA_PFLAG_PIO32 | ATA_PFLAG_PIO32CHANGE;
return ata_bmdma_port_start(ap);
}
EXPORT_SYMBOL_GPL(ata_bmdma_port_start32);
#ifdef CONFIG_PCI
/**
* ata_pci_bmdma_clear_simplex - attempt to kick device out of simplex
* @pdev: PCI device
*
* Some PCI ATA devices report simplex mode but in fact can be told to
* enter non simplex mode. This implements the necessary logic to
* perform the task on such devices. Calling it on other devices will
* have -undefined- behaviour.
*/
int ata_pci_bmdma_clear_simplex(struct pci_dev *pdev)
{
unsigned long bmdma = pci_resource_start(pdev, 4);
u8 simplex;
if (bmdma == 0)
return -ENOENT;
simplex = inb(bmdma + 0x02);
outb(simplex & 0x60, bmdma + 0x02);
simplex = inb(bmdma + 0x02);
if (simplex & 0x80)
return -EOPNOTSUPP;
return 0;
}
EXPORT_SYMBOL_GPL(ata_pci_bmdma_clear_simplex);
static void ata_bmdma_nodma(struct ata_host *host, const char *reason)
{
int i;
dev_err(host->dev, "BMDMA: %s, falling back to PIO\n", reason);
for (i = 0; i < 2; i++) {
host->ports[i]->mwdma_mask = 0;
host->ports[i]->udma_mask = 0;
}
}
/**
* ata_pci_bmdma_init - acquire PCI BMDMA resources and init ATA host
* @host: target ATA host
*
* Acquire PCI BMDMA resources and initialize @host accordingly.
*
* LOCKING:
* Inherited from calling layer (may sleep).
*/
void ata_pci_bmdma_init(struct ata_host *host)
{
struct device *gdev = host->dev;
struct pci_dev *pdev = to_pci_dev(gdev);
int i, rc;
/* No BAR4 allocation: No DMA */
if (pci_resource_start(pdev, 4) == 0) {
ata_bmdma_nodma(host, "BAR4 is zero");
return;
}
/*
* Some controllers require BMDMA region to be initialized
* even if DMA is not in use to clear IRQ status via
* ->sff_irq_clear method. Try to initialize bmdma_addr
* regardless of dma masks.
*/
rc = dma_set_mask_and_coherent(&pdev->dev, ATA_DMA_MASK);
if (rc)
ata_bmdma_nodma(host, "failed to set dma mask");
/* request and iomap DMA region */
rc = pcim_iomap_regions(pdev, 1 << 4, dev_driver_string(gdev));
if (rc) {
ata_bmdma_nodma(host, "failed to request/iomap BAR4");
return;
}
host->iomap = pcim_iomap_table(pdev);
for (i = 0; i < 2; i++) {
struct ata_port *ap = host->ports[i];
void __iomem *bmdma = host->iomap[4] + 8 * i;
if (ata_port_is_dummy(ap))
continue;
ap->ioaddr.bmdma_addr = bmdma;
if ((!(ap->flags & ATA_FLAG_IGN_SIMPLEX)) &&
(ioread8(bmdma + 2) & 0x80))
host->flags |= ATA_HOST_SIMPLEX;
ata_port_desc(ap, "bmdma 0x%llx",
(unsigned long long)pci_resource_start(pdev, 4) + 8 * i);
}
}
EXPORT_SYMBOL_GPL(ata_pci_bmdma_init);
/**
* ata_pci_bmdma_prepare_host - helper to prepare PCI BMDMA ATA host
* @pdev: target PCI device
* @ppi: array of port_info, must be enough for two ports
* @r_host: out argument for the initialized ATA host
*
* Helper to allocate BMDMA ATA host for @pdev, acquire all PCI
* resources and initialize it accordingly in one go.
*
* LOCKING:
* Inherited from calling layer (may sleep).
*
* RETURNS:
* 0 on success, -errno otherwise.
*/
int ata_pci_bmdma_prepare_host(struct pci_dev *pdev,
const struct ata_port_info * const * ppi,
struct ata_host **r_host)
{
int rc;
rc = ata_pci_sff_prepare_host(pdev, ppi, r_host);
if (rc)
return rc;
ata_pci_bmdma_init(*r_host);
return 0;
}
EXPORT_SYMBOL_GPL(ata_pci_bmdma_prepare_host);
/**
* ata_pci_bmdma_init_one - Initialize/register BMDMA PCI IDE controller
* @pdev: Controller to be initialized
* @ppi: array of port_info, must be enough for two ports
* @sht: scsi_host_template to use when registering the host
* @host_priv: host private_data
* @hflags: host flags
*
* This function is similar to ata_pci_sff_init_one() but also
* takes care of BMDMA initialization.
*
* LOCKING:
* Inherited from PCI layer (may sleep).
*
* RETURNS:
* Zero on success, negative on errno-based value on error.
*/
int ata_pci_bmdma_init_one(struct pci_dev *pdev,
const struct ata_port_info * const * ppi,
struct scsi_host_template *sht, void *host_priv,
int hflags)
{
return ata_pci_init_one(pdev, ppi, sht, host_priv, hflags, 1);
}
EXPORT_SYMBOL_GPL(ata_pci_bmdma_init_one);
#endif /* CONFIG_PCI */
#endif /* CONFIG_ATA_BMDMA */
/**
* ata_sff_port_init - Initialize SFF/BMDMA ATA port
* @ap: Port to initialize
*
* Called on port allocation to initialize SFF/BMDMA specific
* fields.
*
* LOCKING:
* None.
*/
void ata_sff_port_init(struct ata_port *ap)
{
INIT_DELAYED_WORK(&ap->sff_pio_task, ata_sff_pio_task);
ap->ctl = ATA_DEVCTL_OBS;
ap->last_ctl = 0xFF;
}
int __init ata_sff_init(void)
{
ata_sff_wq = alloc_workqueue("ata_sff", WQ_MEM_RECLAIM, WQ_MAX_ACTIVE);
if (!ata_sff_wq)
return -ENOMEM;
return 0;
}
void ata_sff_exit(void)
{
destroy_workqueue(ata_sff_wq);
}
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