448 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			448 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0-only
 | 
						|
/*
 | 
						|
 *  Atheros AR724X PCI host controller driver
 | 
						|
 *
 | 
						|
 *  Copyright (C) 2011 René Bolldorf <xsecute@googlemail.com>
 | 
						|
 *  Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org>
 | 
						|
 */
 | 
						|
 | 
						|
#include <linux/irq.h>
 | 
						|
#include <linux/pci.h>
 | 
						|
#include <linux/init.h>
 | 
						|
#include <linux/delay.h>
 | 
						|
#include <linux/platform_device.h>
 | 
						|
#include <asm/mach-ath79/ath79.h>
 | 
						|
#include <asm/mach-ath79/ar71xx_regs.h>
 | 
						|
 | 
						|
#define AR724X_PCI_REG_APP		0x00
 | 
						|
#define AR724X_PCI_REG_RESET		0x18
 | 
						|
#define AR724X_PCI_REG_INT_STATUS	0x4c
 | 
						|
#define AR724X_PCI_REG_INT_MASK		0x50
 | 
						|
 | 
						|
#define AR724X_PCI_APP_LTSSM_ENABLE	BIT(0)
 | 
						|
 | 
						|
#define AR724X_PCI_RESET_LINK_UP	BIT(0)
 | 
						|
 | 
						|
#define AR724X_PCI_INT_DEV0		BIT(14)
 | 
						|
 | 
						|
#define AR724X_PCI_IRQ_COUNT		1
 | 
						|
 | 
						|
#define AR7240_BAR0_WAR_VALUE	0xffff
 | 
						|
 | 
						|
#define AR724X_PCI_CMD_INIT	(PCI_COMMAND_MEMORY |		\
 | 
						|
				 PCI_COMMAND_MASTER |		\
 | 
						|
				 PCI_COMMAND_INVALIDATE |	\
 | 
						|
				 PCI_COMMAND_PARITY |		\
 | 
						|
				 PCI_COMMAND_SERR |		\
 | 
						|
				 PCI_COMMAND_FAST_BACK)
 | 
						|
 | 
						|
struct ar724x_pci_controller {
 | 
						|
	void __iomem *devcfg_base;
 | 
						|
	void __iomem *ctrl_base;
 | 
						|
	void __iomem *crp_base;
 | 
						|
 | 
						|
	int irq;
 | 
						|
	int irq_base;
 | 
						|
 | 
						|
	bool link_up;
 | 
						|
	bool bar0_is_cached;
 | 
						|
	u32  bar0_value;
 | 
						|
 | 
						|
	struct pci_controller pci_controller;
 | 
						|
	struct resource io_res;
 | 
						|
	struct resource mem_res;
 | 
						|
};
 | 
						|
 | 
						|
static inline bool ar724x_pci_check_link(struct ar724x_pci_controller *apc)
 | 
						|
{
 | 
						|
	u32 reset;
 | 
						|
 | 
						|
	reset = __raw_readl(apc->ctrl_base + AR724X_PCI_REG_RESET);
 | 
						|
	return reset & AR724X_PCI_RESET_LINK_UP;
 | 
						|
}
 | 
						|
 | 
						|
static inline struct ar724x_pci_controller *
 | 
						|
pci_bus_to_ar724x_controller(struct pci_bus *bus)
 | 
						|
{
 | 
						|
	struct pci_controller *hose;
 | 
						|
 | 
						|
	hose = (struct pci_controller *) bus->sysdata;
 | 
						|
	return container_of(hose, struct ar724x_pci_controller, pci_controller);
 | 
						|
}
 | 
						|
 | 
						|
static int ar724x_pci_local_write(struct ar724x_pci_controller *apc,
 | 
						|
				  int where, int size, u32 value)
 | 
						|
{
 | 
						|
	void __iomem *base;
 | 
						|
	u32 data;
 | 
						|
	int s;
 | 
						|
 | 
						|
	WARN_ON(where & (size - 1));
 | 
						|
 | 
						|
	if (!apc->link_up)
 | 
						|
		return PCIBIOS_DEVICE_NOT_FOUND;
 | 
						|
 | 
						|
	base = apc->crp_base;
 | 
						|
	data = __raw_readl(base + (where & ~3));
 | 
						|
 | 
						|
	switch (size) {
 | 
						|
	case 1:
 | 
						|
		s = ((where & 3) * 8);
 | 
						|
		data &= ~(0xff << s);
 | 
						|
		data |= ((value & 0xff) << s);
 | 
						|
		break;
 | 
						|
	case 2:
 | 
						|
		s = ((where & 2) * 8);
 | 
						|
		data &= ~(0xffff << s);
 | 
						|
		data |= ((value & 0xffff) << s);
 | 
						|
		break;
 | 
						|
	case 4:
 | 
						|
		data = value;
 | 
						|
		break;
 | 
						|
	default:
 | 
						|
		return PCIBIOS_BAD_REGISTER_NUMBER;
 | 
						|
	}
 | 
						|
 | 
						|
	__raw_writel(data, base + (where & ~3));
 | 
						|
	/* flush write */
 | 
						|
	__raw_readl(base + (where & ~3));
 | 
						|
 | 
						|
	return PCIBIOS_SUCCESSFUL;
 | 
						|
}
 | 
						|
 | 
						|
static int ar724x_pci_read(struct pci_bus *bus, unsigned int devfn, int where,
 | 
						|
			    int size, uint32_t *value)
 | 
						|
{
 | 
						|
	struct ar724x_pci_controller *apc;
 | 
						|
	void __iomem *base;
 | 
						|
	u32 data;
 | 
						|
 | 
						|
	apc = pci_bus_to_ar724x_controller(bus);
 | 
						|
	if (!apc->link_up)
 | 
						|
		return PCIBIOS_DEVICE_NOT_FOUND;
 | 
						|
 | 
						|
	if (devfn)
 | 
						|
		return PCIBIOS_DEVICE_NOT_FOUND;
 | 
						|
 | 
						|
	base = apc->devcfg_base;
 | 
						|
	data = __raw_readl(base + (where & ~3));
 | 
						|
 | 
						|
	switch (size) {
 | 
						|
	case 1:
 | 
						|
		if (where & 1)
 | 
						|
			data >>= 8;
 | 
						|
		if (where & 2)
 | 
						|
			data >>= 16;
 | 
						|
		data &= 0xff;
 | 
						|
		break;
 | 
						|
	case 2:
 | 
						|
		if (where & 2)
 | 
						|
			data >>= 16;
 | 
						|
		data &= 0xffff;
 | 
						|
		break;
 | 
						|
	case 4:
 | 
						|
		break;
 | 
						|
	default:
 | 
						|
		return PCIBIOS_BAD_REGISTER_NUMBER;
 | 
						|
	}
 | 
						|
 | 
						|
	if (where == PCI_BASE_ADDRESS_0 && size == 4 &&
 | 
						|
	    apc->bar0_is_cached) {
 | 
						|
		/* use the cached value */
 | 
						|
		*value = apc->bar0_value;
 | 
						|
	} else {
 | 
						|
		*value = data;
 | 
						|
	}
 | 
						|
 | 
						|
	return PCIBIOS_SUCCESSFUL;
 | 
						|
}
 | 
						|
 | 
						|
static int ar724x_pci_write(struct pci_bus *bus, unsigned int devfn, int where,
 | 
						|
			     int size, uint32_t value)
 | 
						|
{
 | 
						|
	struct ar724x_pci_controller *apc;
 | 
						|
	void __iomem *base;
 | 
						|
	u32 data;
 | 
						|
	int s;
 | 
						|
 | 
						|
	apc = pci_bus_to_ar724x_controller(bus);
 | 
						|
	if (!apc->link_up)
 | 
						|
		return PCIBIOS_DEVICE_NOT_FOUND;
 | 
						|
 | 
						|
	if (devfn)
 | 
						|
		return PCIBIOS_DEVICE_NOT_FOUND;
 | 
						|
 | 
						|
	if (soc_is_ar7240() && where == PCI_BASE_ADDRESS_0 && size == 4) {
 | 
						|
		if (value != 0xffffffff) {
 | 
						|
			/*
 | 
						|
			 * WAR for a hw issue. If the BAR0 register of the
 | 
						|
			 * device is set to the proper base address, the
 | 
						|
			 * memory space of the device is not accessible.
 | 
						|
			 *
 | 
						|
			 * Cache the intended value so it can be read back,
 | 
						|
			 * and write a SoC specific constant value to the
 | 
						|
			 * BAR0 register in order to make the device memory
 | 
						|
			 * accessible.
 | 
						|
			 */
 | 
						|
			apc->bar0_is_cached = true;
 | 
						|
			apc->bar0_value = value;
 | 
						|
 | 
						|
			value = AR7240_BAR0_WAR_VALUE;
 | 
						|
		} else {
 | 
						|
			apc->bar0_is_cached = false;
 | 
						|
		}
 | 
						|
	}
 | 
						|
 | 
						|
	base = apc->devcfg_base;
 | 
						|
	data = __raw_readl(base + (where & ~3));
 | 
						|
 | 
						|
	switch (size) {
 | 
						|
	case 1:
 | 
						|
		s = ((where & 3) * 8);
 | 
						|
		data &= ~(0xff << s);
 | 
						|
		data |= ((value & 0xff) << s);
 | 
						|
		break;
 | 
						|
	case 2:
 | 
						|
		s = ((where & 2) * 8);
 | 
						|
		data &= ~(0xffff << s);
 | 
						|
		data |= ((value & 0xffff) << s);
 | 
						|
		break;
 | 
						|
	case 4:
 | 
						|
		data = value;
 | 
						|
		break;
 | 
						|
	default:
 | 
						|
		return PCIBIOS_BAD_REGISTER_NUMBER;
 | 
						|
	}
 | 
						|
 | 
						|
	__raw_writel(data, base + (where & ~3));
 | 
						|
	/* flush write */
 | 
						|
	__raw_readl(base + (where & ~3));
 | 
						|
 | 
						|
	return PCIBIOS_SUCCESSFUL;
 | 
						|
}
 | 
						|
 | 
						|
static struct pci_ops ar724x_pci_ops = {
 | 
						|
	.read	= ar724x_pci_read,
 | 
						|
	.write	= ar724x_pci_write,
 | 
						|
};
 | 
						|
 | 
						|
static void ar724x_pci_irq_handler(struct irq_desc *desc)
 | 
						|
{
 | 
						|
	struct ar724x_pci_controller *apc;
 | 
						|
	void __iomem *base;
 | 
						|
	u32 pending;
 | 
						|
 | 
						|
	apc = irq_desc_get_handler_data(desc);
 | 
						|
	base = apc->ctrl_base;
 | 
						|
 | 
						|
	pending = __raw_readl(base + AR724X_PCI_REG_INT_STATUS) &
 | 
						|
		  __raw_readl(base + AR724X_PCI_REG_INT_MASK);
 | 
						|
 | 
						|
	if (pending & AR724X_PCI_INT_DEV0)
 | 
						|
		generic_handle_irq(apc->irq_base + 0);
 | 
						|
 | 
						|
	else
 | 
						|
		spurious_interrupt();
 | 
						|
}
 | 
						|
 | 
						|
static void ar724x_pci_irq_unmask(struct irq_data *d)
 | 
						|
{
 | 
						|
	struct ar724x_pci_controller *apc;
 | 
						|
	void __iomem *base;
 | 
						|
	int offset;
 | 
						|
	u32 t;
 | 
						|
 | 
						|
	apc = irq_data_get_irq_chip_data(d);
 | 
						|
	base = apc->ctrl_base;
 | 
						|
	offset = apc->irq_base - d->irq;
 | 
						|
 | 
						|
	switch (offset) {
 | 
						|
	case 0:
 | 
						|
		t = __raw_readl(base + AR724X_PCI_REG_INT_MASK);
 | 
						|
		__raw_writel(t | AR724X_PCI_INT_DEV0,
 | 
						|
			     base + AR724X_PCI_REG_INT_MASK);
 | 
						|
		/* flush write */
 | 
						|
		__raw_readl(base + AR724X_PCI_REG_INT_MASK);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
static void ar724x_pci_irq_mask(struct irq_data *d)
 | 
						|
{
 | 
						|
	struct ar724x_pci_controller *apc;
 | 
						|
	void __iomem *base;
 | 
						|
	int offset;
 | 
						|
	u32 t;
 | 
						|
 | 
						|
	apc = irq_data_get_irq_chip_data(d);
 | 
						|
	base = apc->ctrl_base;
 | 
						|
	offset = apc->irq_base - d->irq;
 | 
						|
 | 
						|
	switch (offset) {
 | 
						|
	case 0:
 | 
						|
		t = __raw_readl(base + AR724X_PCI_REG_INT_MASK);
 | 
						|
		__raw_writel(t & ~AR724X_PCI_INT_DEV0,
 | 
						|
			     base + AR724X_PCI_REG_INT_MASK);
 | 
						|
 | 
						|
		/* flush write */
 | 
						|
		__raw_readl(base + AR724X_PCI_REG_INT_MASK);
 | 
						|
 | 
						|
		t = __raw_readl(base + AR724X_PCI_REG_INT_STATUS);
 | 
						|
		__raw_writel(t | AR724X_PCI_INT_DEV0,
 | 
						|
			     base + AR724X_PCI_REG_INT_STATUS);
 | 
						|
 | 
						|
		/* flush write */
 | 
						|
		__raw_readl(base + AR724X_PCI_REG_INT_STATUS);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
static struct irq_chip ar724x_pci_irq_chip = {
 | 
						|
	.name		= "AR724X PCI ",
 | 
						|
	.irq_mask	= ar724x_pci_irq_mask,
 | 
						|
	.irq_unmask	= ar724x_pci_irq_unmask,
 | 
						|
	.irq_mask_ack	= ar724x_pci_irq_mask,
 | 
						|
};
 | 
						|
 | 
						|
static void ar724x_pci_irq_init(struct ar724x_pci_controller *apc,
 | 
						|
				int id)
 | 
						|
{
 | 
						|
	void __iomem *base;
 | 
						|
	int i;
 | 
						|
 | 
						|
	base = apc->ctrl_base;
 | 
						|
 | 
						|
	__raw_writel(0, base + AR724X_PCI_REG_INT_MASK);
 | 
						|
	__raw_writel(0, base + AR724X_PCI_REG_INT_STATUS);
 | 
						|
 | 
						|
	apc->irq_base = ATH79_PCI_IRQ_BASE + (id * AR724X_PCI_IRQ_COUNT);
 | 
						|
 | 
						|
	for (i = apc->irq_base;
 | 
						|
	     i < apc->irq_base + AR724X_PCI_IRQ_COUNT; i++) {
 | 
						|
		irq_set_chip_and_handler(i, &ar724x_pci_irq_chip,
 | 
						|
					 handle_level_irq);
 | 
						|
		irq_set_chip_data(i, apc);
 | 
						|
	}
 | 
						|
 | 
						|
	irq_set_chained_handler_and_data(apc->irq, ar724x_pci_irq_handler,
 | 
						|
					 apc);
 | 
						|
}
 | 
						|
 | 
						|
static void ar724x_pci_hw_init(struct ar724x_pci_controller *apc)
 | 
						|
{
 | 
						|
	u32 ppl, app;
 | 
						|
	int wait = 0;
 | 
						|
 | 
						|
	/* deassert PCIe host controller and PCIe PHY reset */
 | 
						|
	ath79_device_reset_clear(AR724X_RESET_PCIE);
 | 
						|
	ath79_device_reset_clear(AR724X_RESET_PCIE_PHY);
 | 
						|
 | 
						|
	/* remove the reset of the PCIE PLL */
 | 
						|
	ppl = ath79_pll_rr(AR724X_PLL_REG_PCIE_CONFIG);
 | 
						|
	ppl &= ~AR724X_PLL_REG_PCIE_CONFIG_PPL_RESET;
 | 
						|
	ath79_pll_wr(AR724X_PLL_REG_PCIE_CONFIG, ppl);
 | 
						|
 | 
						|
	/* deassert bypass for the PCIE PLL */
 | 
						|
	ppl = ath79_pll_rr(AR724X_PLL_REG_PCIE_CONFIG);
 | 
						|
	ppl &= ~AR724X_PLL_REG_PCIE_CONFIG_PPL_BYPASS;
 | 
						|
	ath79_pll_wr(AR724X_PLL_REG_PCIE_CONFIG, ppl);
 | 
						|
 | 
						|
	/* set PCIE Application Control to ready */
 | 
						|
	app = __raw_readl(apc->ctrl_base + AR724X_PCI_REG_APP);
 | 
						|
	app |= AR724X_PCI_APP_LTSSM_ENABLE;
 | 
						|
	__raw_writel(app, apc->ctrl_base + AR724X_PCI_REG_APP);
 | 
						|
 | 
						|
	/* wait up to 100ms for PHY link up */
 | 
						|
	do {
 | 
						|
		mdelay(10);
 | 
						|
		wait++;
 | 
						|
	} while (wait < 10 && !ar724x_pci_check_link(apc));
 | 
						|
}
 | 
						|
 | 
						|
static int ar724x_pci_probe(struct platform_device *pdev)
 | 
						|
{
 | 
						|
	struct ar724x_pci_controller *apc;
 | 
						|
	struct resource *res;
 | 
						|
	int id;
 | 
						|
 | 
						|
	id = pdev->id;
 | 
						|
	if (id == -1)
 | 
						|
		id = 0;
 | 
						|
 | 
						|
	apc = devm_kzalloc(&pdev->dev, sizeof(struct ar724x_pci_controller),
 | 
						|
			    GFP_KERNEL);
 | 
						|
	if (!apc)
 | 
						|
		return -ENOMEM;
 | 
						|
 | 
						|
	apc->ctrl_base = devm_platform_ioremap_resource_byname(pdev, "ctrl_base");
 | 
						|
	if (IS_ERR(apc->ctrl_base))
 | 
						|
		return PTR_ERR(apc->ctrl_base);
 | 
						|
 | 
						|
	apc->devcfg_base = devm_platform_ioremap_resource_byname(pdev, "cfg_base");
 | 
						|
	if (IS_ERR(apc->devcfg_base))
 | 
						|
		return PTR_ERR(apc->devcfg_base);
 | 
						|
 | 
						|
	apc->crp_base = devm_platform_ioremap_resource_byname(pdev, "crp_base");
 | 
						|
	if (IS_ERR(apc->crp_base))
 | 
						|
		return PTR_ERR(apc->crp_base);
 | 
						|
 | 
						|
	apc->irq = platform_get_irq(pdev, 0);
 | 
						|
	if (apc->irq < 0)
 | 
						|
		return -EINVAL;
 | 
						|
 | 
						|
	res = platform_get_resource_byname(pdev, IORESOURCE_IO, "io_base");
 | 
						|
	if (!res)
 | 
						|
		return -EINVAL;
 | 
						|
 | 
						|
	apc->io_res.parent = res;
 | 
						|
	apc->io_res.name = "PCI IO space";
 | 
						|
	apc->io_res.start = res->start;
 | 
						|
	apc->io_res.end = res->end;
 | 
						|
	apc->io_res.flags = IORESOURCE_IO;
 | 
						|
 | 
						|
	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mem_base");
 | 
						|
	if (!res)
 | 
						|
		return -EINVAL;
 | 
						|
 | 
						|
	apc->mem_res.parent = res;
 | 
						|
	apc->mem_res.name = "PCI memory space";
 | 
						|
	apc->mem_res.start = res->start;
 | 
						|
	apc->mem_res.end = res->end;
 | 
						|
	apc->mem_res.flags = IORESOURCE_MEM;
 | 
						|
 | 
						|
	apc->pci_controller.pci_ops = &ar724x_pci_ops;
 | 
						|
	apc->pci_controller.io_resource = &apc->io_res;
 | 
						|
	apc->pci_controller.mem_resource = &apc->mem_res;
 | 
						|
 | 
						|
	/*
 | 
						|
	 * Do the full PCIE Root Complex Initialization Sequence if the PCIe
 | 
						|
	 * host controller is in reset.
 | 
						|
	 */
 | 
						|
	if (ath79_reset_rr(AR724X_RESET_REG_RESET_MODULE) & AR724X_RESET_PCIE)
 | 
						|
		ar724x_pci_hw_init(apc);
 | 
						|
 | 
						|
	apc->link_up = ar724x_pci_check_link(apc);
 | 
						|
	if (!apc->link_up)
 | 
						|
		dev_warn(&pdev->dev, "PCIe link is down\n");
 | 
						|
 | 
						|
	ar724x_pci_irq_init(apc, id);
 | 
						|
 | 
						|
	ar724x_pci_local_write(apc, PCI_COMMAND, 4, AR724X_PCI_CMD_INIT);
 | 
						|
 | 
						|
	register_pci_controller(&apc->pci_controller);
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
static struct platform_driver ar724x_pci_driver = {
 | 
						|
	.probe = ar724x_pci_probe,
 | 
						|
	.driver = {
 | 
						|
		.name = "ar724x-pci",
 | 
						|
	},
 | 
						|
};
 | 
						|
 | 
						|
static int __init ar724x_pci_init(void)
 | 
						|
{
 | 
						|
	return platform_driver_register(&ar724x_pci_driver);
 | 
						|
}
 | 
						|
 | 
						|
postcore_initcall(ar724x_pci_init);
 |