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kernel/drivers/char/ipmi/ipmi_si_intf.c

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// SPDX-License-Identifier: GPL-2.0+
/*
* ipmi_si.c
*
* The interface to the IPMI driver for the system interfaces (KCS, SMIC,
* BT).
*
* Author: MontaVista Software, Inc.
* Corey Minyard <minyard@mvista.com>
* source@mvista.com
*
* Copyright 2002 MontaVista Software Inc.
* Copyright 2006 IBM Corp., Christian Krafft <krafft@de.ibm.com>
*/
/*
* This file holds the "policy" for the interface to the SMI state
* machine. It does the configuration, handles timers and interrupts,
* and drives the real SMI state machine.
*/
#define pr_fmt(fmt) "ipmi_si: " fmt
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/timer.h>
#include <linux/errno.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/list.h>
#include <linux/notifier.h>
#include <linux/mutex.h>
#include <linux/kthread.h>
#include <asm/irq.h>
#include <linux/interrupt.h>
#include <linux/rcupdate.h>
#include <linux/ipmi.h>
#include <linux/ipmi_smi.h>
#include "ipmi_si.h"
#include "ipmi_si_sm.h"
#include <linux/string.h>
#include <linux/ctype.h>
/* Measure times between events in the driver. */
#undef DEBUG_TIMING
/* Call every 10 ms. */
#define SI_TIMEOUT_TIME_USEC 10000
#define SI_USEC_PER_JIFFY (1000000/HZ)
#define SI_TIMEOUT_JIFFIES (SI_TIMEOUT_TIME_USEC/SI_USEC_PER_JIFFY)
#define SI_SHORT_TIMEOUT_USEC 250 /* .25ms when the SM request a
short timeout */
enum si_intf_state {
SI_NORMAL,
SI_GETTING_FLAGS,
SI_GETTING_EVENTS,
SI_CLEARING_FLAGS,
SI_GETTING_MESSAGES,
SI_CHECKING_ENABLES,
SI_SETTING_ENABLES
/* FIXME - add watchdog stuff. */
};
/* Some BT-specific defines we need here. */
#define IPMI_BT_INTMASK_REG 2
#define IPMI_BT_INTMASK_CLEAR_IRQ_BIT 2
#define IPMI_BT_INTMASK_ENABLE_IRQ_BIT 1
/* 'invalid' to allow a firmware-specified interface to be disabled */
const char *const si_to_str[] = { "invalid", "kcs", "smic", "bt", NULL };
static bool initialized;
/*
* Indexes into stats[] in smi_info below.
*/
enum si_stat_indexes {
/*
* Number of times the driver requested a timer while an operation
* was in progress.
*/
SI_STAT_short_timeouts = 0,
/*
* Number of times the driver requested a timer while nothing was in
* progress.
*/
SI_STAT_long_timeouts,
/* Number of times the interface was idle while being polled. */
SI_STAT_idles,
/* Number of interrupts the driver handled. */
SI_STAT_interrupts,
/* Number of time the driver got an ATTN from the hardware. */
SI_STAT_attentions,
/* Number of times the driver requested flags from the hardware. */
SI_STAT_flag_fetches,
/* Number of times the hardware didn't follow the state machine. */
SI_STAT_hosed_count,
/* Number of completed messages. */
SI_STAT_complete_transactions,
/* Number of IPMI events received from the hardware. */
SI_STAT_events,
/* Number of watchdog pretimeouts. */
SI_STAT_watchdog_pretimeouts,
/* Number of asynchronous messages received. */
SI_STAT_incoming_messages,
/* This *must* remain last, add new values above this. */
SI_NUM_STATS
};
struct smi_info {
int si_num;
struct ipmi_smi *intf;
struct si_sm_data *si_sm;
const struct si_sm_handlers *handlers;
spinlock_t si_lock;
struct ipmi_smi_msg *waiting_msg;
struct ipmi_smi_msg *curr_msg;
enum si_intf_state si_state;
/*
* Used to handle the various types of I/O that can occur with
* IPMI
*/
struct si_sm_io io;
/*
* Per-OEM handler, called from handle_flags(). Returns 1
* when handle_flags() needs to be re-run or 0 indicating it
* set si_state itself.
*/
int (*oem_data_avail_handler)(struct smi_info *smi_info);
/*
* Flags from the last GET_MSG_FLAGS command, used when an ATTN
* is set to hold the flags until we are done handling everything
* from the flags.
*/
#define RECEIVE_MSG_AVAIL 0x01
#define EVENT_MSG_BUFFER_FULL 0x02
#define WDT_PRE_TIMEOUT_INT 0x08
#define OEM0_DATA_AVAIL 0x20
#define OEM1_DATA_AVAIL 0x40
#define OEM2_DATA_AVAIL 0x80
#define OEM_DATA_AVAIL (OEM0_DATA_AVAIL | \
OEM1_DATA_AVAIL | \
OEM2_DATA_AVAIL)
unsigned char msg_flags;
/* Does the BMC have an event buffer? */
bool has_event_buffer;
/*
* If set to true, this will request events the next time the
* state machine is idle.
*/
atomic_t req_events;
/*
* If true, run the state machine to completion on every send
* call. Generally used after a panic to make sure stuff goes
* out.
*/
bool run_to_completion;
/* The timer for this si. */
struct timer_list si_timer;
/* This flag is set, if the timer can be set */
bool timer_can_start;
/* This flag is set, if the timer is running (timer_pending() isn't enough) */
bool timer_running;
/* The time (in jiffies) the last timeout occurred at. */
unsigned long last_timeout_jiffies;
/* Are we waiting for the events, pretimeouts, received msgs? */
atomic_t need_watch;
/*
* The driver will disable interrupts when it gets into a
* situation where it cannot handle messages due to lack of
* memory. Once that situation clears up, it will re-enable
* interrupts.
*/
bool interrupt_disabled;
/*
* Does the BMC support events?
*/
bool supports_event_msg_buff;
/*
* Can we disable interrupts the global enables receive irq
* bit? There are currently two forms of brokenness, some
* systems cannot disable the bit (which is technically within
* the spec but a bad idea) and some systems have the bit
* forced to zero even though interrupts work (which is
* clearly outside the spec). The next bool tells which form
* of brokenness is present.
*/
bool cannot_disable_irq;
/*
* Some systems are broken and cannot set the irq enable
* bit, even if they support interrupts.
*/
bool irq_enable_broken;
/* Is the driver in maintenance mode? */
bool in_maintenance_mode;
/*
* Did we get an attention that we did not handle?
*/
bool got_attn;
/* From the get device id response... */
struct ipmi_device_id device_id;
/* Have we added the device group to the device? */
bool dev_group_added;
/* Counters and things for the proc filesystem. */
atomic_t stats[SI_NUM_STATS];
struct task_struct *thread;
struct list_head link;
};
#define smi_inc_stat(smi, stat) \
atomic_inc(&(smi)->stats[SI_STAT_ ## stat])
#define smi_get_stat(smi, stat) \
((unsigned int) atomic_read(&(smi)->stats[SI_STAT_ ## stat]))
#define IPMI_MAX_INTFS 4
static int force_kipmid[IPMI_MAX_INTFS];
static int num_force_kipmid;
static unsigned int kipmid_max_busy_us[IPMI_MAX_INTFS];
static int num_max_busy_us;
static bool unload_when_empty = true;
static int try_smi_init(struct smi_info *smi);
static void cleanup_one_si(struct smi_info *smi_info);
static void cleanup_ipmi_si(void);
#ifdef DEBUG_TIMING
void debug_timestamp(struct smi_info *smi_info, char *msg)
{
struct timespec64 t;
ktime_get_ts64(&t);
dev_dbg(smi_info->io.dev, "**%s: %lld.%9.9ld\n",
msg, t.tv_sec, t.tv_nsec);
}
#else
#define debug_timestamp(smi_info, x)
#endif
static ATOMIC_NOTIFIER_HEAD(xaction_notifier_list);
static int register_xaction_notifier(struct notifier_block *nb)
{
return atomic_notifier_chain_register(&xaction_notifier_list, nb);
}
static void deliver_recv_msg(struct smi_info *smi_info,
struct ipmi_smi_msg *msg)
{
/* Deliver the message to the upper layer. */
ipmi_smi_msg_received(smi_info->intf, msg);
}
static void return_hosed_msg(struct smi_info *smi_info, int cCode)
{
struct ipmi_smi_msg *msg = smi_info->curr_msg;
if (cCode < 0 || cCode > IPMI_ERR_UNSPECIFIED)
cCode = IPMI_ERR_UNSPECIFIED;
/* else use it as is */
/* Make it a response */
msg->rsp[0] = msg->data[0] | 4;
msg->rsp[1] = msg->data[1];
msg->rsp[2] = cCode;
msg->rsp_size = 3;
smi_info->curr_msg = NULL;
deliver_recv_msg(smi_info, msg);
}
static enum si_sm_result start_next_msg(struct smi_info *smi_info)
{
int rv;
if (!smi_info->waiting_msg) {
smi_info->curr_msg = NULL;
rv = SI_SM_IDLE;
} else {
int err;
smi_info->curr_msg = smi_info->waiting_msg;
smi_info->waiting_msg = NULL;
debug_timestamp(smi_info, "Start2");
err = atomic_notifier_call_chain(&xaction_notifier_list,
0, smi_info);
if (err & NOTIFY_STOP_MASK) {
rv = SI_SM_CALL_WITHOUT_DELAY;
goto out;
}
err = smi_info->handlers->start_transaction(
smi_info->si_sm,
smi_info->curr_msg->data,
smi_info->curr_msg->data_size);
if (err)
return_hosed_msg(smi_info, err);
rv = SI_SM_CALL_WITHOUT_DELAY;
}
out:
return rv;
}
static void smi_mod_timer(struct smi_info *smi_info, unsigned long new_val)
{
if (!smi_info->timer_can_start)
return;
smi_info->last_timeout_jiffies = jiffies;
mod_timer(&smi_info->si_timer, new_val);
smi_info->timer_running = true;
}
/*
* Start a new message and (re)start the timer and thread.
*/
static void start_new_msg(struct smi_info *smi_info, unsigned char *msg,
unsigned int size)
{
smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
if (smi_info->thread)
wake_up_process(smi_info->thread);
smi_info->handlers->start_transaction(smi_info->si_sm, msg, size);
}
static void start_check_enables(struct smi_info *smi_info)
{
unsigned char msg[2];
msg[0] = (IPMI_NETFN_APP_REQUEST << 2);
msg[1] = IPMI_GET_BMC_GLOBAL_ENABLES_CMD;
start_new_msg(smi_info, msg, 2);
smi_info->si_state = SI_CHECKING_ENABLES;
}
static void start_clear_flags(struct smi_info *smi_info)
{
unsigned char msg[3];
/* Make sure the watchdog pre-timeout flag is not set at startup. */
msg[0] = (IPMI_NETFN_APP_REQUEST << 2);
msg[1] = IPMI_CLEAR_MSG_FLAGS_CMD;
msg[2] = WDT_PRE_TIMEOUT_INT;
start_new_msg(smi_info, msg, 3);
smi_info->si_state = SI_CLEARING_FLAGS;
}
static void start_getting_msg_queue(struct smi_info *smi_info)
{
smi_info->curr_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
smi_info->curr_msg->data[1] = IPMI_GET_MSG_CMD;
smi_info->curr_msg->data_size = 2;
start_new_msg(smi_info, smi_info->curr_msg->data,
smi_info->curr_msg->data_size);
smi_info->si_state = SI_GETTING_MESSAGES;
}
static void start_getting_events(struct smi_info *smi_info)
{
smi_info->curr_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
smi_info->curr_msg->data[1] = IPMI_READ_EVENT_MSG_BUFFER_CMD;
smi_info->curr_msg->data_size = 2;
start_new_msg(smi_info, smi_info->curr_msg->data,
smi_info->curr_msg->data_size);
smi_info->si_state = SI_GETTING_EVENTS;
}
/*
* When we have a situtaion where we run out of memory and cannot
* allocate messages, we just leave them in the BMC and run the system
* polled until we can allocate some memory. Once we have some
* memory, we will re-enable the interrupt.
*
* Note that we cannot just use disable_irq(), since the interrupt may
* be shared.
*/
static inline bool disable_si_irq(struct smi_info *smi_info)
{
if ((smi_info->io.irq) && (!smi_info->interrupt_disabled)) {
smi_info->interrupt_disabled = true;
start_check_enables(smi_info);
return true;
}
return false;
}
static inline bool enable_si_irq(struct smi_info *smi_info)
{
if ((smi_info->io.irq) && (smi_info->interrupt_disabled)) {
smi_info->interrupt_disabled = false;
start_check_enables(smi_info);
return true;
}
return false;
}
/*
* Allocate a message. If unable to allocate, start the interrupt
* disable process and return NULL. If able to allocate but
* interrupts are disabled, free the message and return NULL after
* starting the interrupt enable process.
*/
static struct ipmi_smi_msg *alloc_msg_handle_irq(struct smi_info *smi_info)
{
struct ipmi_smi_msg *msg;
msg = ipmi_alloc_smi_msg();
if (!msg) {
if (!disable_si_irq(smi_info))
smi_info->si_state = SI_NORMAL;
} else if (enable_si_irq(smi_info)) {
ipmi_free_smi_msg(msg);
msg = NULL;
}
return msg;
}
static void handle_flags(struct smi_info *smi_info)
{
retry:
if (smi_info->msg_flags & WDT_PRE_TIMEOUT_INT) {
/* Watchdog pre-timeout */
smi_inc_stat(smi_info, watchdog_pretimeouts);
start_clear_flags(smi_info);
smi_info->msg_flags &= ~WDT_PRE_TIMEOUT_INT;
ipmi_smi_watchdog_pretimeout(smi_info->intf);
} else if (smi_info->msg_flags & RECEIVE_MSG_AVAIL) {
/* Messages available. */
smi_info->curr_msg = alloc_msg_handle_irq(smi_info);
if (!smi_info->curr_msg)
return;
start_getting_msg_queue(smi_info);
} else if (smi_info->msg_flags & EVENT_MSG_BUFFER_FULL) {
/* Events available. */
smi_info->curr_msg = alloc_msg_handle_irq(smi_info);
if (!smi_info->curr_msg)
return;
start_getting_events(smi_info);
} else if (smi_info->msg_flags & OEM_DATA_AVAIL &&
smi_info->oem_data_avail_handler) {
if (smi_info->oem_data_avail_handler(smi_info))
goto retry;
} else
smi_info->si_state = SI_NORMAL;
}
/*
* Global enables we care about.
*/
#define GLOBAL_ENABLES_MASK (IPMI_BMC_EVT_MSG_BUFF | IPMI_BMC_RCV_MSG_INTR | \
IPMI_BMC_EVT_MSG_INTR)
static u8 current_global_enables(struct smi_info *smi_info, u8 base,
bool *irq_on)
{
u8 enables = 0;
if (smi_info->supports_event_msg_buff)
enables |= IPMI_BMC_EVT_MSG_BUFF;
if (((smi_info->io.irq && !smi_info->interrupt_disabled) ||
smi_info->cannot_disable_irq) &&
!smi_info->irq_enable_broken)
enables |= IPMI_BMC_RCV_MSG_INTR;
if (smi_info->supports_event_msg_buff &&
smi_info->io.irq && !smi_info->interrupt_disabled &&
!smi_info->irq_enable_broken)
enables |= IPMI_BMC_EVT_MSG_INTR;
*irq_on = enables & (IPMI_BMC_EVT_MSG_INTR | IPMI_BMC_RCV_MSG_INTR);
return enables;
}
static void check_bt_irq(struct smi_info *smi_info, bool irq_on)
{
u8 irqstate = smi_info->io.inputb(&smi_info->io, IPMI_BT_INTMASK_REG);
irqstate &= IPMI_BT_INTMASK_ENABLE_IRQ_BIT;
if ((bool)irqstate == irq_on)
return;
if (irq_on)
smi_info->io.outputb(&smi_info->io, IPMI_BT_INTMASK_REG,
IPMI_BT_INTMASK_ENABLE_IRQ_BIT);
else
smi_info->io.outputb(&smi_info->io, IPMI_BT_INTMASK_REG, 0);
}
static void handle_transaction_done(struct smi_info *smi_info)
{
struct ipmi_smi_msg *msg;
debug_timestamp(smi_info, "Done");
switch (smi_info->si_state) {
case SI_NORMAL:
if (!smi_info->curr_msg)
break;
smi_info->curr_msg->rsp_size
= smi_info->handlers->get_result(
smi_info->si_sm,
smi_info->curr_msg->rsp,
IPMI_MAX_MSG_LENGTH);
/*
* Do this here becase deliver_recv_msg() releases the
* lock, and a new message can be put in during the
* time the lock is released.
*/
msg = smi_info->curr_msg;
smi_info->curr_msg = NULL;
deliver_recv_msg(smi_info, msg);
break;
case SI_GETTING_FLAGS:
{
unsigned char msg[4];
unsigned int len;
/* We got the flags from the SMI, now handle them. */
len = smi_info->handlers->get_result(smi_info->si_sm, msg, 4);
if (msg[2] != 0) {
/* Error fetching flags, just give up for now. */
smi_info->si_state = SI_NORMAL;
} else if (len < 4) {
/*
* Hmm, no flags. That's technically illegal, but
* don't use uninitialized data.
*/
smi_info->si_state = SI_NORMAL;
} else {
smi_info->msg_flags = msg[3];
handle_flags(smi_info);
}
break;
}
case SI_CLEARING_FLAGS:
{
unsigned char msg[3];
/* We cleared the flags. */
smi_info->handlers->get_result(smi_info->si_sm, msg, 3);
if (msg[2] != 0) {
/* Error clearing flags */
dev_warn_ratelimited(smi_info->io.dev,
"Error clearing flags: %2.2x\n", msg[2]);
}
smi_info->si_state = SI_NORMAL;
break;
}
case SI_GETTING_EVENTS:
{
smi_info->curr_msg->rsp_size
= smi_info->handlers->get_result(
smi_info->si_sm,
smi_info->curr_msg->rsp,
IPMI_MAX_MSG_LENGTH);
/*
* Do this here becase deliver_recv_msg() releases the
* lock, and a new message can be put in during the
* time the lock is released.
*/
msg = smi_info->curr_msg;
smi_info->curr_msg = NULL;
if (msg->rsp[2] != 0) {
/* Error getting event, probably done. */
msg->done(msg);
/* Take off the event flag. */
smi_info->msg_flags &= ~EVENT_MSG_BUFFER_FULL;
handle_flags(smi_info);
} else {
smi_inc_stat(smi_info, events);
/*
* Do this before we deliver the message
* because delivering the message releases the
* lock and something else can mess with the
* state.
*/
handle_flags(smi_info);
deliver_recv_msg(smi_info, msg);
}
break;
}
case SI_GETTING_MESSAGES:
{
smi_info->curr_msg->rsp_size
= smi_info->handlers->get_result(
smi_info->si_sm,
smi_info->curr_msg->rsp,
IPMI_MAX_MSG_LENGTH);
/*
* Do this here becase deliver_recv_msg() releases the
* lock, and a new message can be put in during the
* time the lock is released.
*/
msg = smi_info->curr_msg;
smi_info->curr_msg = NULL;
if (msg->rsp[2] != 0) {
/* Error getting event, probably done. */
msg->done(msg);
/* Take off the msg flag. */
smi_info->msg_flags &= ~RECEIVE_MSG_AVAIL;
handle_flags(smi_info);
} else {
smi_inc_stat(smi_info, incoming_messages);
/*
* Do this before we deliver the message
* because delivering the message releases the
* lock and something else can mess with the
* state.
*/
handle_flags(smi_info);
deliver_recv_msg(smi_info, msg);
}
break;
}
case SI_CHECKING_ENABLES:
{
unsigned char msg[4];
u8 enables;
bool irq_on;
/* We got the flags from the SMI, now handle them. */
smi_info->handlers->get_result(smi_info->si_sm, msg, 4);
if (msg[2] != 0) {
dev_warn_ratelimited(smi_info->io.dev,
"Couldn't get irq info: %x,\n"
"Maybe ok, but ipmi might run very slowly.\n",
msg[2]);
smi_info->si_state = SI_NORMAL;
break;
}
enables = current_global_enables(smi_info, 0, &irq_on);
if (smi_info->io.si_type == SI_BT)
/* BT has its own interrupt enable bit. */
check_bt_irq(smi_info, irq_on);
if (enables != (msg[3] & GLOBAL_ENABLES_MASK)) {
/* Enables are not correct, fix them. */
msg[0] = (IPMI_NETFN_APP_REQUEST << 2);
msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD;
msg[2] = enables | (msg[3] & ~GLOBAL_ENABLES_MASK);
smi_info->handlers->start_transaction(
smi_info->si_sm, msg, 3);
smi_info->si_state = SI_SETTING_ENABLES;
} else if (smi_info->supports_event_msg_buff) {
smi_info->curr_msg = ipmi_alloc_smi_msg();
if (!smi_info->curr_msg) {
smi_info->si_state = SI_NORMAL;
break;
}
start_getting_events(smi_info);
} else {
smi_info->si_state = SI_NORMAL;
}
break;
}
case SI_SETTING_ENABLES:
{
unsigned char msg[4];
smi_info->handlers->get_result(smi_info->si_sm, msg, 4);
if (msg[2] != 0)
dev_warn_ratelimited(smi_info->io.dev,
"Could not set the global enables: 0x%x.\n",
msg[2]);
if (smi_info->supports_event_msg_buff) {
smi_info->curr_msg = ipmi_alloc_smi_msg();
if (!smi_info->curr_msg) {
smi_info->si_state = SI_NORMAL;
break;
}
start_getting_events(smi_info);
} else {
smi_info->si_state = SI_NORMAL;
}
break;
}
}
}
/*
* Called on timeouts and events. Timeouts should pass the elapsed
* time, interrupts should pass in zero. Must be called with
* si_lock held and interrupts disabled.
*/
static enum si_sm_result smi_event_handler(struct smi_info *smi_info,
int time)
{
enum si_sm_result si_sm_result;
restart:
/*
* There used to be a loop here that waited a little while
* (around 25us) before giving up. That turned out to be
* pointless, the minimum delays I was seeing were in the 300us
* range, which is far too long to wait in an interrupt. So
* we just run until the state machine tells us something
* happened or it needs a delay.
*/
si_sm_result = smi_info->handlers->event(smi_info->si_sm, time);
time = 0;
while (si_sm_result == SI_SM_CALL_WITHOUT_DELAY)
si_sm_result = smi_info->handlers->event(smi_info->si_sm, 0);
if (si_sm_result == SI_SM_TRANSACTION_COMPLETE) {
smi_inc_stat(smi_info, complete_transactions);
handle_transaction_done(smi_info);
goto restart;
} else if (si_sm_result == SI_SM_HOSED) {
smi_inc_stat(smi_info, hosed_count);
/*
* Do the before return_hosed_msg, because that
* releases the lock.
*/
smi_info->si_state = SI_NORMAL;
if (smi_info->curr_msg != NULL) {
/*
* If we were handling a user message, format
* a response to send to the upper layer to
* tell it about the error.
*/
return_hosed_msg(smi_info, IPMI_ERR_UNSPECIFIED);
}
goto restart;
}
/*
* We prefer handling attn over new messages. But don't do
* this if there is not yet an upper layer to handle anything.
*/
if (si_sm_result == SI_SM_ATTN || smi_info->got_attn) {
unsigned char msg[2];
if (smi_info->si_state != SI_NORMAL) {
/*
* We got an ATTN, but we are doing something else.
* Handle the ATTN later.
*/
smi_info->got_attn = true;
} else {
smi_info->got_attn = false;
smi_inc_stat(smi_info, attentions);
/*
* Got a attn, send down a get message flags to see
* what's causing it. It would be better to handle
* this in the upper layer, but due to the way
* interrupts work with the SMI, that's not really
* possible.
*/
msg[0] = (IPMI_NETFN_APP_REQUEST << 2);
msg[1] = IPMI_GET_MSG_FLAGS_CMD;
start_new_msg(smi_info, msg, 2);
smi_info->si_state = SI_GETTING_FLAGS;
goto restart;
}
}
/* If we are currently idle, try to start the next message. */
if (si_sm_result == SI_SM_IDLE) {
smi_inc_stat(smi_info, idles);
si_sm_result = start_next_msg(smi_info);
if (si_sm_result != SI_SM_IDLE)
goto restart;
}
if ((si_sm_result == SI_SM_IDLE)
&& (atomic_read(&smi_info->req_events))) {
/*
* We are idle and the upper layer requested that I fetch
* events, so do so.
*/
atomic_set(&smi_info->req_events, 0);
/*
* Take this opportunity to check the interrupt and
* message enable state for the BMC. The BMC can be
* asynchronously reset, and may thus get interrupts
* disable and messages disabled.
*/
if (smi_info->supports_event_msg_buff || smi_info->io.irq) {
start_check_enables(smi_info);
} else {
smi_info->curr_msg = alloc_msg_handle_irq(smi_info);
if (!smi_info->curr_msg)
goto out;
start_getting_events(smi_info);
}
goto restart;
}
if (si_sm_result == SI_SM_IDLE && smi_info->timer_running) {
/* Ok it if fails, the timer will just go off. */
if (del_timer(&smi_info->si_timer))
smi_info->timer_running = false;
}
out:
return si_sm_result;
}
static void check_start_timer_thread(struct smi_info *smi_info)
{
if (smi_info->si_state == SI_NORMAL && smi_info->curr_msg == NULL) {
smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
if (smi_info->thread)
wake_up_process(smi_info->thread);
start_next_msg(smi_info);
smi_event_handler(smi_info, 0);
}
}
static void flush_messages(void *send_info)
{
struct smi_info *smi_info = send_info;
enum si_sm_result result;
/*
* Currently, this function is called only in run-to-completion
* mode. This means we are single-threaded, no need for locks.
*/
result = smi_event_handler(smi_info, 0);
while (result != SI_SM_IDLE) {
udelay(SI_SHORT_TIMEOUT_USEC);
result = smi_event_handler(smi_info, SI_SHORT_TIMEOUT_USEC);
}
}
static void sender(void *send_info,
struct ipmi_smi_msg *msg)
{
struct smi_info *smi_info = send_info;
unsigned long flags;
debug_timestamp(smi_info, "Enqueue");
if (smi_info->run_to_completion) {
/*
* If we are running to completion, start it. Upper
* layer will call flush_messages to clear it out.
*/
smi_info->waiting_msg = msg;
return;
}
spin_lock_irqsave(&smi_info->si_lock, flags);
/*
* The following two lines don't need to be under the lock for
* the lock's sake, but they do need SMP memory barriers to
* avoid getting things out of order. We are already claiming
* the lock, anyway, so just do it under the lock to avoid the
* ordering problem.
*/
BUG_ON(smi_info->waiting_msg);
smi_info->waiting_msg = msg;
check_start_timer_thread(smi_info);
spin_unlock_irqrestore(&smi_info->si_lock, flags);
}
static void set_run_to_completion(void *send_info, bool i_run_to_completion)
{
struct smi_info *smi_info = send_info;
smi_info->run_to_completion = i_run_to_completion;
if (i_run_to_completion)
flush_messages(smi_info);
}
/*
* Use -1 as a special constant to tell that we are spinning in kipmid
* looking for something and not delaying between checks
*/
#define IPMI_TIME_NOT_BUSY ns_to_ktime(-1ull)
static inline bool ipmi_thread_busy_wait(enum si_sm_result smi_result,
const struct smi_info *smi_info,
ktime_t *busy_until)
{
unsigned int max_busy_us = 0;
if (smi_info->si_num < num_max_busy_us)
max_busy_us = kipmid_max_busy_us[smi_info->si_num];
if (max_busy_us == 0 || smi_result != SI_SM_CALL_WITH_DELAY)
*busy_until = IPMI_TIME_NOT_BUSY;
else if (*busy_until == IPMI_TIME_NOT_BUSY) {
*busy_until = ktime_get() + max_busy_us * NSEC_PER_USEC;
} else {
if (unlikely(ktime_get() > *busy_until)) {
*busy_until = IPMI_TIME_NOT_BUSY;
return false;
}
}
return true;
}
/*
* A busy-waiting loop for speeding up IPMI operation.
*
* Lousy hardware makes this hard. This is only enabled for systems
* that are not BT and do not have interrupts. It starts spinning
* when an operation is complete or until max_busy tells it to stop
* (if that is enabled). See the paragraph on kimid_max_busy_us in
* Documentation/driver-api/ipmi.rst for details.
*/
static int ipmi_thread(void *data)
{
struct smi_info *smi_info = data;
unsigned long flags;
enum si_sm_result smi_result;
ktime_t busy_until = IPMI_TIME_NOT_BUSY;
set_user_nice(current, MAX_NICE);
while (!kthread_should_stop()) {
int busy_wait;
spin_lock_irqsave(&(smi_info->si_lock), flags);
smi_result = smi_event_handler(smi_info, 0);
/*
* If the driver is doing something, there is a possible
* race with the timer. If the timer handler see idle,
* and the thread here sees something else, the timer
* handler won't restart the timer even though it is
* required. So start it here if necessary.
*/
if (smi_result != SI_SM_IDLE && !smi_info->timer_running)
smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
spin_unlock_irqrestore(&(smi_info->si_lock), flags);
busy_wait = ipmi_thread_busy_wait(smi_result, smi_info,
&busy_until);
if (smi_result == SI_SM_CALL_WITHOUT_DELAY) {
; /* do nothing */
} else if (smi_result == SI_SM_CALL_WITH_DELAY && busy_wait) {
/*
* In maintenance mode we run as fast as
* possible to allow firmware updates to
* complete as fast as possible, but normally
* don't bang on the scheduler.
*/
if (smi_info->in_maintenance_mode)
schedule();
else
usleep_range(100, 200);
} else if (smi_result == SI_SM_IDLE) {
if (atomic_read(&smi_info->need_watch)) {
schedule_timeout_interruptible(100);
} else {
/* Wait to be woken up when we are needed. */
__set_current_state(TASK_INTERRUPTIBLE);
schedule();
}
} else {
schedule_timeout_interruptible(1);
}
}
return 0;
}
static void poll(void *send_info)
{
struct smi_info *smi_info = send_info;
unsigned long flags = 0;
bool run_to_completion = smi_info->run_to_completion;
/*
* Make sure there is some delay in the poll loop so we can
* drive time forward and timeout things.
*/
udelay(10);
if (!run_to_completion)
spin_lock_irqsave(&smi_info->si_lock, flags);
smi_event_handler(smi_info, 10);
if (!run_to_completion)
spin_unlock_irqrestore(&smi_info->si_lock, flags);
}
static void request_events(void *send_info)
{
struct smi_info *smi_info = send_info;
if (!smi_info->has_event_buffer)
return;
atomic_set(&smi_info->req_events, 1);
}
static void set_need_watch(void *send_info, unsigned int watch_mask)
{
struct smi_info *smi_info = send_info;
unsigned long flags;
int enable;
enable = !!watch_mask;
atomic_set(&smi_info->need_watch, enable);
spin_lock_irqsave(&smi_info->si_lock, flags);
check_start_timer_thread(smi_info);
spin_unlock_irqrestore(&smi_info->si_lock, flags);
}
static void smi_timeout(struct timer_list *t)
{
struct smi_info *smi_info = from_timer(smi_info, t, si_timer);
enum si_sm_result smi_result;
unsigned long flags;
unsigned long jiffies_now;
long time_diff;
long timeout;
spin_lock_irqsave(&(smi_info->si_lock), flags);
debug_timestamp(smi_info, "Timer");
jiffies_now = jiffies;
time_diff = (((long)jiffies_now - (long)smi_info->last_timeout_jiffies)
* SI_USEC_PER_JIFFY);
smi_result = smi_event_handler(smi_info, time_diff);
if ((smi_info->io.irq) && (!smi_info->interrupt_disabled)) {
/* Running with interrupts, only do long timeouts. */
timeout = jiffies + SI_TIMEOUT_JIFFIES;
smi_inc_stat(smi_info, long_timeouts);
goto do_mod_timer;
}
/*
* If the state machine asks for a short delay, then shorten
* the timer timeout.
*/
if (smi_result == SI_SM_CALL_WITH_DELAY) {
smi_inc_stat(smi_info, short_timeouts);
timeout = jiffies + 1;
} else {
smi_inc_stat(smi_info, long_timeouts);
timeout = jiffies + SI_TIMEOUT_JIFFIES;
}
do_mod_timer:
if (smi_result != SI_SM_IDLE)
smi_mod_timer(smi_info, timeout);
else
smi_info->timer_running = false;
spin_unlock_irqrestore(&(smi_info->si_lock), flags);
}
irqreturn_t ipmi_si_irq_handler(int irq, void *data)
{
struct smi_info *smi_info = data;
unsigned long flags;
if (smi_info->io.si_type == SI_BT)
/* We need to clear the IRQ flag for the BT interface. */
smi_info->io.outputb(&smi_info->io, IPMI_BT_INTMASK_REG,
IPMI_BT_INTMASK_CLEAR_IRQ_BIT
| IPMI_BT_INTMASK_ENABLE_IRQ_BIT);
spin_lock_irqsave(&(smi_info->si_lock), flags);
smi_inc_stat(smi_info, interrupts);
debug_timestamp(smi_info, "Interrupt");
smi_event_handler(smi_info, 0);
spin_unlock_irqrestore(&(smi_info->si_lock), flags);
return IRQ_HANDLED;
}
static int smi_start_processing(void *send_info,
struct ipmi_smi *intf)
{
struct smi_info *new_smi = send_info;
int enable = 0;
new_smi->intf = intf;
/* Set up the timer that drives the interface. */
timer_setup(&new_smi->si_timer, smi_timeout, 0);
new_smi->timer_can_start = true;
smi_mod_timer(new_smi, jiffies + SI_TIMEOUT_JIFFIES);
/* Try to claim any interrupts. */
if (new_smi->io.irq_setup) {
new_smi->io.irq_handler_data = new_smi;
new_smi->io.irq_setup(&new_smi->io);
}
/*
* Check if the user forcefully enabled the daemon.
*/
if (new_smi->si_num < num_force_kipmid)
enable = force_kipmid[new_smi->si_num];
/*
* The BT interface is efficient enough to not need a thread,
* and there is no need for a thread if we have interrupts.
*/
else if ((new_smi->io.si_type != SI_BT) && (!new_smi->io.irq))
enable = 1;
if (enable) {
new_smi->thread = kthread_run(ipmi_thread, new_smi,
"kipmi%d", new_smi->si_num);
if (IS_ERR(new_smi->thread)) {
dev_notice(new_smi->io.dev,
"Could not start kernel thread due to error %ld, only using timers to drive the interface\n",
PTR_ERR(new_smi->thread));
new_smi->thread = NULL;
}
}
return 0;
}
static int get_smi_info(void *send_info, struct ipmi_smi_info *data)
{
struct smi_info *smi = send_info;
data->addr_src = smi->io.addr_source;
data->dev = smi->io.dev;
data->addr_info = smi->io.addr_info;
get_device(smi->io.dev);
return 0;
}
static void set_maintenance_mode(void *send_info, bool enable)
{
struct smi_info *smi_info = send_info;
if (!enable)
atomic_set(&smi_info->req_events, 0);
smi_info->in_maintenance_mode = enable;
}
static void shutdown_smi(void *send_info);
static const struct ipmi_smi_handlers handlers = {
.owner = THIS_MODULE,
.start_processing = smi_start_processing,
.shutdown = shutdown_smi,
.get_smi_info = get_smi_info,
.sender = sender,
.request_events = request_events,
.set_need_watch = set_need_watch,
.set_maintenance_mode = set_maintenance_mode,
.set_run_to_completion = set_run_to_completion,
.flush_messages = flush_messages,
.poll = poll,
};
static LIST_HEAD(smi_infos);
static DEFINE_MUTEX(smi_infos_lock);
static int smi_num; /* Used to sequence the SMIs */
static const char * const addr_space_to_str[] = { "i/o", "mem" };
module_param_array(force_kipmid, int, &num_force_kipmid, 0);
MODULE_PARM_DESC(force_kipmid,
"Force the kipmi daemon to be enabled (1) or disabled(0). Normally the IPMI driver auto-detects this, but the value may be overridden by this parm.");
module_param(unload_when_empty, bool, 0);
MODULE_PARM_DESC(unload_when_empty,
"Unload the module if no interfaces are specified or found, default is 1. Setting to 0 is useful for hot add of devices using hotmod.");
module_param_array(kipmid_max_busy_us, uint, &num_max_busy_us, 0644);
MODULE_PARM_DESC(kipmid_max_busy_us,
"Max time (in microseconds) to busy-wait for IPMI data before sleeping. 0 (default) means to wait forever. Set to 100-500 if kipmid is using up a lot of CPU time.");
void ipmi_irq_finish_setup(struct si_sm_io *io)
{
if (io->si_type == SI_BT)
/* Enable the interrupt in the BT interface. */
io->outputb(io, IPMI_BT_INTMASK_REG,
IPMI_BT_INTMASK_ENABLE_IRQ_BIT);
}
void ipmi_irq_start_cleanup(struct si_sm_io *io)
{
if (io->si_type == SI_BT)
/* Disable the interrupt in the BT interface. */
io->outputb(io, IPMI_BT_INTMASK_REG, 0);
}
static void std_irq_cleanup(struct si_sm_io *io)
{
ipmi_irq_start_cleanup(io);
free_irq(io->irq, io->irq_handler_data);
}
int ipmi_std_irq_setup(struct si_sm_io *io)
{
int rv;
if (!io->irq)
return 0;
rv = request_irq(io->irq,
ipmi_si_irq_handler,
IRQF_SHARED,
SI_DEVICE_NAME,
io->irq_handler_data);
if (rv) {
dev_warn(io->dev, "%s unable to claim interrupt %d, running polled\n",
SI_DEVICE_NAME, io->irq);
io->irq = 0;
} else {
io->irq_cleanup = std_irq_cleanup;
ipmi_irq_finish_setup(io);
dev_info(io->dev, "Using irq %d\n", io->irq);
}
return rv;
}
static int wait_for_msg_done(struct smi_info *smi_info)
{
enum si_sm_result smi_result;
smi_result = smi_info->handlers->event(smi_info->si_sm, 0);
for (;;) {
if (smi_result == SI_SM_CALL_WITH_DELAY ||
smi_result == SI_SM_CALL_WITH_TICK_DELAY) {
schedule_timeout_uninterruptible(1);
smi_result = smi_info->handlers->event(
smi_info->si_sm, jiffies_to_usecs(1));
} else if (smi_result == SI_SM_CALL_WITHOUT_DELAY) {
smi_result = smi_info->handlers->event(
smi_info->si_sm, 0);
} else
break;
}
if (smi_result == SI_SM_HOSED)
/*
* We couldn't get the state machine to run, so whatever's at
* the port is probably not an IPMI SMI interface.
*/
return -ENODEV;
return 0;
}
static int try_get_dev_id(struct smi_info *smi_info)
{
unsigned char msg[2];
unsigned char *resp;
unsigned long resp_len;
int rv = 0;
unsigned int retry_count = 0;
resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
if (!resp)
return -ENOMEM;
/*
* Do a Get Device ID command, since it comes back with some
* useful info.
*/
msg[0] = IPMI_NETFN_APP_REQUEST << 2;
msg[1] = IPMI_GET_DEVICE_ID_CMD;
retry:
smi_info->handlers->start_transaction(smi_info->si_sm, msg, 2);
rv = wait_for_msg_done(smi_info);
if (rv)
goto out;
resp_len = smi_info->handlers->get_result(smi_info->si_sm,
resp, IPMI_MAX_MSG_LENGTH);
/* Check and record info from the get device id, in case we need it. */
rv = ipmi_demangle_device_id(resp[0] >> 2, resp[1],
resp + 2, resp_len - 2, &smi_info->device_id);
if (rv) {
/* record completion code */
unsigned char cc = *(resp + 2);
if (cc != IPMI_CC_NO_ERROR &&
++retry_count <= GET_DEVICE_ID_MAX_RETRY) {
dev_warn_ratelimited(smi_info->io.dev,
"BMC returned 0x%2.2x, retry get bmc device id\n",
cc);
goto retry;
}
}
out:
kfree(resp);
return rv;
}
static int get_global_enables(struct smi_info *smi_info, u8 *enables)
{
unsigned char msg[3];
unsigned char *resp;
unsigned long resp_len;
int rv;
resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
if (!resp)
return -ENOMEM;
msg[0] = IPMI_NETFN_APP_REQUEST << 2;
msg[1] = IPMI_GET_BMC_GLOBAL_ENABLES_CMD;
smi_info->handlers->start_transaction(smi_info->si_sm, msg, 2);
rv = wait_for_msg_done(smi_info);
if (rv) {
dev_warn(smi_info->io.dev,
"Error getting response from get global enables command: %d\n",
rv);
goto out;
}
resp_len = smi_info->handlers->get_result(smi_info->si_sm,
resp, IPMI_MAX_MSG_LENGTH);
if (resp_len < 4 ||
resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 ||
resp[1] != IPMI_GET_BMC_GLOBAL_ENABLES_CMD ||
resp[2] != 0) {
dev_warn(smi_info->io.dev,
"Invalid return from get global enables command: %ld %x %x %x\n",
resp_len, resp[0], resp[1], resp[2]);
rv = -EINVAL;
goto out;
} else {
*enables = resp[3];
}
out:
kfree(resp);
return rv;
}
/*
* Returns 1 if it gets an error from the command.
*/
static int set_global_enables(struct smi_info *smi_info, u8 enables)
{
unsigned char msg[3];
unsigned char *resp;
unsigned long resp_len;
int rv;
resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
if (!resp)
return -ENOMEM;
msg[0] = IPMI_NETFN_APP_REQUEST << 2;
msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD;
msg[2] = enables;
smi_info->handlers->start_transaction(smi_info->si_sm, msg, 3);
rv = wait_for_msg_done(smi_info);
if (rv) {
dev_warn(smi_info->io.dev,
"Error getting response from set global enables command: %d\n",
rv);
goto out;
}
resp_len = smi_info->handlers->get_result(smi_info->si_sm,
resp, IPMI_MAX_MSG_LENGTH);
if (resp_len < 3 ||
resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 ||
resp[1] != IPMI_SET_BMC_GLOBAL_ENABLES_CMD) {
dev_warn(smi_info->io.dev,
"Invalid return from set global enables command: %ld %x %x\n",
resp_len, resp[0], resp[1]);
rv = -EINVAL;
goto out;
}
if (resp[2] != 0)
rv = 1;
out:
kfree(resp);
return rv;
}
/*
* Some BMCs do not support clearing the receive irq bit in the global
* enables (even if they don't support interrupts on the BMC). Check
* for this and handle it properly.
*/
static void check_clr_rcv_irq(struct smi_info *smi_info)
{
u8 enables = 0;
int rv;
rv = get_global_enables(smi_info, &enables);
if (!rv) {
if ((enables & IPMI_BMC_RCV_MSG_INTR) == 0)
/* Already clear, should work ok. */
return;
enables &= ~IPMI_BMC_RCV_MSG_INTR;
rv = set_global_enables(smi_info, enables);
}
if (rv < 0) {
dev_err(smi_info->io.dev,
"Cannot check clearing the rcv irq: %d\n", rv);
return;
}
if (rv) {
/*
* An error when setting the event buffer bit means
* clearing the bit is not supported.
*/
dev_warn(smi_info->io.dev,
"The BMC does not support clearing the recv irq bit, compensating, but the BMC needs to be fixed.\n");
smi_info->cannot_disable_irq = true;
}
}
/*
* Some BMCs do not support setting the interrupt bits in the global
* enables even if they support interrupts. Clearly bad, but we can
* compensate.
*/
static void check_set_rcv_irq(struct smi_info *smi_info)
{
u8 enables = 0;
int rv;
if (!smi_info->io.irq)
return;
rv = get_global_enables(smi_info, &enables);
if (!rv) {
enables |= IPMI_BMC_RCV_MSG_INTR;
rv = set_global_enables(smi_info, enables);
}
if (rv < 0) {
dev_err(smi_info->io.dev,
"Cannot check setting the rcv irq: %d\n", rv);
return;
}
if (rv) {
/*
* An error when setting the event buffer bit means
* setting the bit is not supported.
*/
dev_warn(smi_info->io.dev,
"The BMC does not support setting the recv irq bit, compensating, but the BMC needs to be fixed.\n");
smi_info->cannot_disable_irq = true;
smi_info->irq_enable_broken = true;
}
}
static int try_enable_event_buffer(struct smi_info *smi_info)
{
unsigned char msg[3];
unsigned char *resp;
unsigned long resp_len;
int rv = 0;
resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
if (!resp)
return -ENOMEM;
msg[0] = IPMI_NETFN_APP_REQUEST << 2;
msg[1] = IPMI_GET_BMC_GLOBAL_ENABLES_CMD;
smi_info->handlers->start_transaction(smi_info->si_sm, msg, 2);
rv = wait_for_msg_done(smi_info);
if (rv) {
pr_warn("Error getting response from get global enables command, the event buffer is not enabled\n");
goto out;
}
resp_len = smi_info->handlers->get_result(smi_info->si_sm,
resp, IPMI_MAX_MSG_LENGTH);
if (resp_len < 4 ||
resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 ||
resp[1] != IPMI_GET_BMC_GLOBAL_ENABLES_CMD ||
resp[2] != 0) {
pr_warn("Invalid return from get global enables command, cannot enable the event buffer\n");
rv = -EINVAL;
goto out;
}
if (resp[3] & IPMI_BMC_EVT_MSG_BUFF) {
/* buffer is already enabled, nothing to do. */
smi_info->supports_event_msg_buff = true;
goto out;
}
msg[0] = IPMI_NETFN_APP_REQUEST << 2;
msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD;
msg[2] = resp[3] | IPMI_BMC_EVT_MSG_BUFF;
smi_info->handlers->start_transaction(smi_info->si_sm, msg, 3);
rv = wait_for_msg_done(smi_info);
if (rv) {
pr_warn("Error getting response from set global, enables command, the event buffer is not enabled\n");
goto out;
}
resp_len = smi_info->handlers->get_result(smi_info->si_sm,
resp, IPMI_MAX_MSG_LENGTH);
if (resp_len < 3 ||
resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 ||
resp[1] != IPMI_SET_BMC_GLOBAL_ENABLES_CMD) {
pr_warn("Invalid return from get global, enables command, not enable the event buffer\n");
rv = -EINVAL;
goto out;
}
if (resp[2] != 0)
/*
* An error when setting the event buffer bit means
* that the event buffer is not supported.
*/
rv = -ENOENT;
else
smi_info->supports_event_msg_buff = true;
out:
kfree(resp);
return rv;
}
#define IPMI_SI_ATTR(name) \
static ssize_t name##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
struct smi_info *smi_info = dev_get_drvdata(dev); \
\
return sysfs_emit(buf, "%u\n", smi_get_stat(smi_info, name)); \
} \
static DEVICE_ATTR_RO(name)
static ssize_t type_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct smi_info *smi_info = dev_get_drvdata(dev);
return sysfs_emit(buf, "%s\n", si_to_str[smi_info->io.si_type]);
}
static DEVICE_ATTR_RO(type);
static ssize_t interrupts_enabled_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct smi_info *smi_info = dev_get_drvdata(dev);
int enabled = smi_info->io.irq && !smi_info->interrupt_disabled;
return sysfs_emit(buf, "%d\n", enabled);
}
static DEVICE_ATTR_RO(interrupts_enabled);
IPMI_SI_ATTR(short_timeouts);
IPMI_SI_ATTR(long_timeouts);
IPMI_SI_ATTR(idles);
IPMI_SI_ATTR(interrupts);
IPMI_SI_ATTR(attentions);
IPMI_SI_ATTR(flag_fetches);
IPMI_SI_ATTR(hosed_count);
IPMI_SI_ATTR(complete_transactions);
IPMI_SI_ATTR(events);
IPMI_SI_ATTR(watchdog_pretimeouts);
IPMI_SI_ATTR(incoming_messages);
static ssize_t params_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct smi_info *smi_info = dev_get_drvdata(dev);
return sysfs_emit(buf,
"%s,%s,0x%lx,rsp=%d,rsi=%d,rsh=%d,irq=%d,ipmb=%d\n",
si_to_str[smi_info->io.si_type],
addr_space_to_str[smi_info->io.addr_space],
smi_info->io.addr_data,
smi_info->io.regspacing,
smi_info->io.regsize,
smi_info->io.regshift,
smi_info->io.irq,
smi_info->io.slave_addr);
}
static DEVICE_ATTR_RO(params);
static struct attribute *ipmi_si_dev_attrs[] = {
&dev_attr_type.attr,
&dev_attr_interrupts_enabled.attr,
&dev_attr_short_timeouts.attr,
&dev_attr_long_timeouts.attr,
&dev_attr_idles.attr,
&dev_attr_interrupts.attr,
&dev_attr_attentions.attr,
&dev_attr_flag_fetches.attr,
&dev_attr_hosed_count.attr,
&dev_attr_complete_transactions.attr,
&dev_attr_events.attr,
&dev_attr_watchdog_pretimeouts.attr,
&dev_attr_incoming_messages.attr,
&dev_attr_params.attr,
NULL
};
static const struct attribute_group ipmi_si_dev_attr_group = {
.attrs = ipmi_si_dev_attrs,
};
/*
* oem_data_avail_to_receive_msg_avail
* @info - smi_info structure with msg_flags set
*
* Converts flags from OEM_DATA_AVAIL to RECEIVE_MSG_AVAIL
* Returns 1 indicating need to re-run handle_flags().
*/
static int oem_data_avail_to_receive_msg_avail(struct smi_info *smi_info)
{
smi_info->msg_flags = ((smi_info->msg_flags & ~OEM_DATA_AVAIL) |
RECEIVE_MSG_AVAIL);
return 1;
}
/*
* setup_dell_poweredge_oem_data_handler
* @info - smi_info.device_id must be populated
*
* Systems that match, but have firmware version < 1.40 may assert
* OEM0_DATA_AVAIL on their own, without being told via Set Flags that
* it's safe to do so. Such systems will de-assert OEM1_DATA_AVAIL
* upon receipt of IPMI_GET_MSG_CMD, so we should treat these flags
* as RECEIVE_MSG_AVAIL instead.
*
* As Dell has no plans to release IPMI 1.5 firmware that *ever*
* assert the OEM[012] bits, and if it did, the driver would have to
* change to handle that properly, we don't actually check for the
* firmware version.
* Device ID = 0x20 BMC on PowerEdge 8G servers
* Device Revision = 0x80
* Firmware Revision1 = 0x01 BMC version 1.40
* Firmware Revision2 = 0x40 BCD encoded
* IPMI Version = 0x51 IPMI 1.5
* Manufacturer ID = A2 02 00 Dell IANA
*
* Additionally, PowerEdge systems with IPMI < 1.5 may also assert
* OEM0_DATA_AVAIL and needs to be treated as RECEIVE_MSG_AVAIL.
*
*/
#define DELL_POWEREDGE_8G_BMC_DEVICE_ID 0x20
#define DELL_POWEREDGE_8G_BMC_DEVICE_REV 0x80
#define DELL_POWEREDGE_8G_BMC_IPMI_VERSION 0x51
#define DELL_IANA_MFR_ID 0x0002a2
static void setup_dell_poweredge_oem_data_handler(struct smi_info *smi_info)
{
struct ipmi_device_id *id = &smi_info->device_id;
if (id->manufacturer_id == DELL_IANA_MFR_ID) {
if (id->device_id == DELL_POWEREDGE_8G_BMC_DEVICE_ID &&
id->device_revision == DELL_POWEREDGE_8G_BMC_DEVICE_REV &&
id->ipmi_version == DELL_POWEREDGE_8G_BMC_IPMI_VERSION) {
smi_info->oem_data_avail_handler =
oem_data_avail_to_receive_msg_avail;
} else if (ipmi_version_major(id) < 1 ||
(ipmi_version_major(id) == 1 &&
ipmi_version_minor(id) < 5)) {
smi_info->oem_data_avail_handler =
oem_data_avail_to_receive_msg_avail;
}
}
}
#define CANNOT_RETURN_REQUESTED_LENGTH 0xCA
static void return_hosed_msg_badsize(struct smi_info *smi_info)
{
struct ipmi_smi_msg *msg = smi_info->curr_msg;
/* Make it a response */
msg->rsp[0] = msg->data[0] | 4;
msg->rsp[1] = msg->data[1];
msg->rsp[2] = CANNOT_RETURN_REQUESTED_LENGTH;
msg->rsp_size = 3;
smi_info->curr_msg = NULL;
deliver_recv_msg(smi_info, msg);
}
/*
* dell_poweredge_bt_xaction_handler
* @info - smi_info.device_id must be populated
*
* Dell PowerEdge servers with the BT interface (x6xx and 1750) will
* not respond to a Get SDR command if the length of the data
* requested is exactly 0x3A, which leads to command timeouts and no
* data returned. This intercepts such commands, and causes userspace
* callers to try again with a different-sized buffer, which succeeds.
*/
#define STORAGE_NETFN 0x0A
#define STORAGE_CMD_GET_SDR 0x23
static int dell_poweredge_bt_xaction_handler(struct notifier_block *self,
unsigned long unused,
void *in)
{
struct smi_info *smi_info = in;
unsigned char *data = smi_info->curr_msg->data;
unsigned int size = smi_info->curr_msg->data_size;
if (size >= 8 &&
(data[0]>>2) == STORAGE_NETFN &&
data[1] == STORAGE_CMD_GET_SDR &&
data[7] == 0x3A) {
return_hosed_msg_badsize(smi_info);
return NOTIFY_STOP;
}
return NOTIFY_DONE;
}
static struct notifier_block dell_poweredge_bt_xaction_notifier = {
.notifier_call = dell_poweredge_bt_xaction_handler,
};
/*
* setup_dell_poweredge_bt_xaction_handler
* @info - smi_info.device_id must be filled in already
*
* Fills in smi_info.device_id.start_transaction_pre_hook
* when we know what function to use there.
*/
static void
setup_dell_poweredge_bt_xaction_handler(struct smi_info *smi_info)
{
struct ipmi_device_id *id = &smi_info->device_id;
if (id->manufacturer_id == DELL_IANA_MFR_ID &&
smi_info->io.si_type == SI_BT)
register_xaction_notifier(&dell_poweredge_bt_xaction_notifier);
}
/*
* setup_oem_data_handler
* @info - smi_info.device_id must be filled in already
*
* Fills in smi_info.device_id.oem_data_available_handler
* when we know what function to use there.
*/
static void setup_oem_data_handler(struct smi_info *smi_info)
{
setup_dell_poweredge_oem_data_handler(smi_info);
}
static void setup_xaction_handlers(struct smi_info *smi_info)
{
setup_dell_poweredge_bt_xaction_handler(smi_info);
}
static void check_for_broken_irqs(struct smi_info *smi_info)
{
check_clr_rcv_irq(smi_info);
check_set_rcv_irq(smi_info);
}
static inline void stop_timer_and_thread(struct smi_info *smi_info)
{
if (smi_info->thread != NULL) {
kthread_stop(smi_info->thread);
smi_info->thread = NULL;
}
smi_info->timer_can_start = false;
del_timer_sync(&smi_info->si_timer);
}
static struct smi_info *find_dup_si(struct smi_info *info)
{
struct smi_info *e;
list_for_each_entry(e, &smi_infos, link) {
if (e->io.addr_space != info->io.addr_space)
continue;
if (e->io.addr_data == info->io.addr_data) {
/*
* This is a cheap hack, ACPI doesn't have a defined
* slave address but SMBIOS does. Pick it up from
* any source that has it available.
*/
if (info->io.slave_addr && !e->io.slave_addr)
e->io.slave_addr = info->io.slave_addr;
return e;
}
}
return NULL;
}
int ipmi_si_add_smi(struct si_sm_io *io)
{
int rv = 0;
struct smi_info *new_smi, *dup;
/*
* If the user gave us a hard-coded device at the same
* address, they presumably want us to use it and not what is
* in the firmware.
*/
if (io->addr_source != SI_HARDCODED && io->addr_source != SI_HOTMOD &&
ipmi_si_hardcode_match(io->addr_space, io->addr_data)) {
dev_info(io->dev,
"Hard-coded device at this address already exists");
return -ENODEV;
}
if (!io->io_setup) {
if (IS_ENABLED(CONFIG_HAS_IOPORT) &&
io->addr_space == IPMI_IO_ADDR_SPACE) {
io->io_setup = ipmi_si_port_setup;
} else if (io->addr_space == IPMI_MEM_ADDR_SPACE) {
io->io_setup = ipmi_si_mem_setup;
} else {
return -EINVAL;
}
}
new_smi = kzalloc(sizeof(*new_smi), GFP_KERNEL);
if (!new_smi)
return -ENOMEM;
spin_lock_init(&new_smi->si_lock);
new_smi->io = *io;
mutex_lock(&smi_infos_lock);
dup = find_dup_si(new_smi);
if (dup) {
if (new_smi->io.addr_source == SI_ACPI &&
dup->io.addr_source == SI_SMBIOS) {
/* We prefer ACPI over SMBIOS. */
dev_info(dup->io.dev,
"Removing SMBIOS-specified %s state machine in favor of ACPI\n",
si_to_str[new_smi->io.si_type]);
cleanup_one_si(dup);
} else {
dev_info(new_smi->io.dev,
"%s-specified %s state machine: duplicate\n",
ipmi_addr_src_to_str(new_smi->io.addr_source),
si_to_str[new_smi->io.si_type]);
rv = -EBUSY;
kfree(new_smi);
goto out_err;
}
}
pr_info("Adding %s-specified %s state machine\n",
ipmi_addr_src_to_str(new_smi->io.addr_source),
si_to_str[new_smi->io.si_type]);
list_add_tail(&new_smi->link, &smi_infos);
if (initialized)
rv = try_smi_init(new_smi);
out_err:
mutex_unlock(&smi_infos_lock);
return rv;
}
/*
* Try to start up an interface. Must be called with smi_infos_lock
* held, primarily to keep smi_num consistent, we only one to do these
* one at a time.
*/
static int try_smi_init(struct smi_info *new_smi)
{
int rv = 0;
int i;
pr_info("Trying %s-specified %s state machine at %s address 0x%lx, slave address 0x%x, irq %d\n",
ipmi_addr_src_to_str(new_smi->io.addr_source),
si_to_str[new_smi->io.si_type],
addr_space_to_str[new_smi->io.addr_space],
new_smi->io.addr_data,
new_smi->io.slave_addr, new_smi->io.irq);
switch (new_smi->io.si_type) {
case SI_KCS:
new_smi->handlers = &kcs_smi_handlers;
break;
case SI_SMIC:
new_smi->handlers = &smic_smi_handlers;
break;
case SI_BT:
new_smi->handlers = &bt_smi_handlers;
break;
default:
/* No support for anything else yet. */
rv = -EIO;
goto out_err;
}
new_smi->si_num = smi_num;
/* Do this early so it's available for logs. */
if (!new_smi->io.dev) {
pr_err("IPMI interface added with no device\n");
rv = -EIO;
goto out_err;
}
/* Allocate the state machine's data and initialize it. */
new_smi->si_sm = kmalloc(new_smi->handlers->size(), GFP_KERNEL);
if (!new_smi->si_sm) {
rv = -ENOMEM;
goto out_err;
}
new_smi->io.io_size = new_smi->handlers->init_data(new_smi->si_sm,
&new_smi->io);
/* Now that we know the I/O size, we can set up the I/O. */
rv = new_smi->io.io_setup(&new_smi->io);
if (rv) {
dev_err(new_smi->io.dev, "Could not set up I/O space\n");
goto out_err;
}
/* Do low-level detection first. */
if (new_smi->handlers->detect(new_smi->si_sm)) {
if (new_smi->io.addr_source)
dev_err(new_smi->io.dev,
"Interface detection failed\n");
rv = -ENODEV;
goto out_err;
}
/*
* Attempt a get device id command. If it fails, we probably
* don't have a BMC here.
*/
rv = try_get_dev_id(new_smi);
if (rv) {
if (new_smi->io.addr_source)
dev_err(new_smi->io.dev,
"There appears to be no BMC at this location\n");
goto out_err;
}
setup_oem_data_handler(new_smi);
setup_xaction_handlers(new_smi);
check_for_broken_irqs(new_smi);
new_smi->waiting_msg = NULL;
new_smi->curr_msg = NULL;
atomic_set(&new_smi->req_events, 0);
new_smi->run_to_completion = false;
for (i = 0; i < SI_NUM_STATS; i++)
atomic_set(&new_smi->stats[i], 0);
new_smi->interrupt_disabled = true;
atomic_set(&new_smi->need_watch, 0);
rv = try_enable_event_buffer(new_smi);
if (rv == 0)
new_smi->has_event_buffer = true;
/*
* Start clearing the flags before we enable interrupts or the
* timer to avoid racing with the timer.
*/
start_clear_flags(new_smi);
/*
* IRQ is defined to be set when non-zero. req_events will
* cause a global flags check that will enable interrupts.
*/
if (new_smi->io.irq) {
new_smi->interrupt_disabled = false;
atomic_set(&new_smi->req_events, 1);
}
dev_set_drvdata(new_smi->io.dev, new_smi);
rv = device_add_group(new_smi->io.dev, &ipmi_si_dev_attr_group);
if (rv) {
dev_err(new_smi->io.dev,
"Unable to add device attributes: error %d\n",
rv);
goto out_err;
}
new_smi->dev_group_added = true;
rv = ipmi_register_smi(&handlers,
new_smi,
new_smi->io.dev,
new_smi->io.slave_addr);
if (rv) {
dev_err(new_smi->io.dev,
"Unable to register device: error %d\n",
rv);
goto out_err;
}
/* Don't increment till we know we have succeeded. */
smi_num++;
dev_info(new_smi->io.dev, "IPMI %s interface initialized\n",
si_to_str[new_smi->io.si_type]);
WARN_ON(new_smi->io.dev->init_name != NULL);
out_err:
if (rv && new_smi->io.io_cleanup) {
new_smi->io.io_cleanup(&new_smi->io);
new_smi->io.io_cleanup = NULL;
}
if (rv && new_smi->si_sm) {
kfree(new_smi->si_sm);
new_smi->si_sm = NULL;
}
return rv;
}
static int __init init_ipmi_si(void)
{
struct smi_info *e;
enum ipmi_addr_src type = SI_INVALID;
if (initialized)
return 0;
ipmi_hardcode_init();
pr_info("IPMI System Interface driver\n");
ipmi_si_platform_init();
ipmi_si_pci_init();
ipmi_si_parisc_init();
/* We prefer devices with interrupts, but in the case of a machine
with multiple BMCs we assume that there will be several instances
of a given type so if we succeed in registering a type then also
try to register everything else of the same type */
mutex_lock(&smi_infos_lock);
list_for_each_entry(e, &smi_infos, link) {
/* Try to register a device if it has an IRQ and we either
haven't successfully registered a device yet or this
device has the same type as one we successfully registered */
if (e->io.irq && (!type || e->io.addr_source == type)) {
if (!try_smi_init(e)) {
type = e->io.addr_source;
}
}
}
/* type will only have been set if we successfully registered an si */
if (type)
goto skip_fallback_noirq;
/* Fall back to the preferred device */
list_for_each_entry(e, &smi_infos, link) {
if (!e->io.irq && (!type || e->io.addr_source == type)) {
if (!try_smi_init(e)) {
type = e->io.addr_source;
}
}
}
skip_fallback_noirq:
initialized = true;
mutex_unlock(&smi_infos_lock);
if (type)
return 0;
mutex_lock(&smi_infos_lock);
if (unload_when_empty && list_empty(&smi_infos)) {
mutex_unlock(&smi_infos_lock);
cleanup_ipmi_si();
pr_warn("Unable to find any System Interface(s)\n");
return -ENODEV;
} else {
mutex_unlock(&smi_infos_lock);
return 0;
}
}
module_init(init_ipmi_si);
static void wait_msg_processed(struct smi_info *smi_info)
{
unsigned long jiffies_now;
long time_diff;
while (smi_info->curr_msg || (smi_info->si_state != SI_NORMAL)) {
jiffies_now = jiffies;
time_diff = (((long)jiffies_now - (long)smi_info->last_timeout_jiffies)
* SI_USEC_PER_JIFFY);
smi_event_handler(smi_info, time_diff);
schedule_timeout_uninterruptible(1);
}
}
static void shutdown_smi(void *send_info)
{
struct smi_info *smi_info = send_info;
if (smi_info->dev_group_added) {
device_remove_group(smi_info->io.dev, &ipmi_si_dev_attr_group);
smi_info->dev_group_added = false;
}
if (smi_info->io.dev)
dev_set_drvdata(smi_info->io.dev, NULL);
/*
* Make sure that interrupts, the timer and the thread are
* stopped and will not run again.
*/
smi_info->interrupt_disabled = true;
if (smi_info->io.irq_cleanup) {
smi_info->io.irq_cleanup(&smi_info->io);
smi_info->io.irq_cleanup = NULL;
}
stop_timer_and_thread(smi_info);
/*
* Wait until we know that we are out of any interrupt
* handlers might have been running before we freed the
* interrupt.
*/
synchronize_rcu();
/*
* Timeouts are stopped, now make sure the interrupts are off
* in the BMC. Note that timers and CPU interrupts are off,
* so no need for locks.
*/
wait_msg_processed(smi_info);
if (smi_info->handlers)
disable_si_irq(smi_info);
wait_msg_processed(smi_info);
if (smi_info->handlers)
smi_info->handlers->cleanup(smi_info->si_sm);
if (smi_info->io.io_cleanup) {
smi_info->io.io_cleanup(&smi_info->io);
smi_info->io.io_cleanup = NULL;
}
kfree(smi_info->si_sm);
smi_info->si_sm = NULL;
smi_info->intf = NULL;
}
/*
* Must be called with smi_infos_lock held, to serialize the
* smi_info->intf check.
*/
static void cleanup_one_si(struct smi_info *smi_info)
{
if (!smi_info)
return;
list_del(&smi_info->link);
ipmi_unregister_smi(smi_info->intf);
kfree(smi_info);
}
void ipmi_si_remove_by_dev(struct device *dev)
{
struct smi_info *e;
mutex_lock(&smi_infos_lock);
list_for_each_entry(e, &smi_infos, link) {
if (e->io.dev == dev) {
cleanup_one_si(e);
break;
}
}
mutex_unlock(&smi_infos_lock);
}
struct device *ipmi_si_remove_by_data(int addr_space, enum si_type si_type,
unsigned long addr)
{
/* remove */
struct smi_info *e, *tmp_e;
struct device *dev = NULL;
mutex_lock(&smi_infos_lock);
list_for_each_entry_safe(e, tmp_e, &smi_infos, link) {
if (e->io.addr_space != addr_space)
continue;
if (e->io.si_type != si_type)
continue;
if (e->io.addr_data == addr) {
dev = get_device(e->io.dev);
cleanup_one_si(e);
}
}
mutex_unlock(&smi_infos_lock);
return dev;
}
static void cleanup_ipmi_si(void)
{
struct smi_info *e, *tmp_e;
if (!initialized)
return;
ipmi_si_pci_shutdown();
ipmi_si_parisc_shutdown();
ipmi_si_platform_shutdown();
mutex_lock(&smi_infos_lock);
list_for_each_entry_safe(e, tmp_e, &smi_infos, link)
cleanup_one_si(e);
mutex_unlock(&smi_infos_lock);
ipmi_si_hardcode_exit();
ipmi_si_hotmod_exit();
}
module_exit(cleanup_ipmi_si);
MODULE_ALIAS("platform:dmi-ipmi-si");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>");
MODULE_DESCRIPTION("Interface to the IPMI driver for the KCS, SMIC, and BT system interfaces.");
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