arch/arm/mach-cns3xxx/pcie.c - arm/linux - Git at Google

 /*
  * PCI-E support for CNS3xxx
  *
  * Copyright 2008 Cavium Networks
  *		  Richard Liu <richard.liu@caviumnetworks.com>
  * Copyright 2010 MontaVista Software, LLC.
  *		  Anton Vorontsov <avorontsov@mvista.com>
  *
  * This file is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License, Version 2, as
  * published by the Free Software Foundation.
  */

 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/bug.h>
 #include <linux/pci.h>
 #include <linux/io.h>
 #include <linux/ioport.h>
 #include <linux/interrupt.h>
 #include <linux/ptrace.h>
 #include <asm/mach/map.h>
 #include "cns3xxx.h"
 #include "core.h"

 struct cns3xxx_pcie {
 	void __iomem *host_regs; /* PCI config registers for host bridge */
 	void __iomem *cfg0_regs; /* PCI Type 0 config registers */
 	void __iomem *cfg1_regs; /* PCI Type 1 config registers */
 	unsigned int irqs[2];
 	struct resource res_io;
 	struct resource res_mem;
 	int port;
 	bool linked;
 };

 static struct cns3xxx_pcie *sysdata_to_cnspci(void *sysdata)
 {
 	struct pci_sys_data *root = sysdata;

 	return root->private_data;
 }

 static struct cns3xxx_pcie *pdev_to_cnspci(const struct pci_dev *dev)
 {
 	return sysdata_to_cnspci(dev->sysdata);
 }

 static struct cns3xxx_pcie *pbus_to_cnspci(struct pci_bus *bus)
 {
 	return sysdata_to_cnspci(bus->sysdata);
 }

 static void __iomem *cns3xxx_pci_map_bus(struct pci_bus *bus,
 					 unsigned int devfn, int where)
 {
 	struct cns3xxx_pcie *cnspci = pbus_to_cnspci(bus);
 	int busno = bus->number;
 	int slot = PCI_SLOT(devfn);
 	void __iomem *base;

 	/* If there is no link, just show the CNS PCI bridge. */
 	if (!cnspci->linked && busno > 0)
 		return NULL;

 	/*
 	 * The CNS PCI bridge doesn't fit into the PCI hierarchy, though
 	 * we still want to access it.
 	 * We place the host bridge on bus 0, and the directly connected
 	 * device on bus 1, slot 0.
 	 */
 	if (busno == 0) { /* internal PCIe bus, host bridge device */
 		if (devfn == 0) /* device# and function# are ignored by hw */
 			base = cnspci->host_regs;
 		else
 			return NULL; /* no such device */

 	} else if (busno == 1) { /* directly connected PCIe device */
 		if (slot == 0) /* device# is ignored by hw */
 			base = cnspci->cfg0_regs;
 		else
 			return NULL; /* no such device */
 	} else /* remote PCI bus */
 		base = cnspci->cfg1_regs + ((busno & 0xf) << 20);

 	return base + (where & 0xffc) + (devfn << 12);
 }

 static int cns3xxx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
 				   int where, int size, u32 *val)
 {
 	int ret;
 	u32 mask = (0x1ull << (size * 8)) - 1;
 	int shift = (where % 4) * 8;

 	ret = pci_generic_config_read32(bus, devfn, where, size, val);

 	if (ret == PCIBIOS_SUCCESSFUL && !bus->number && !devfn &&
 	    (where & 0xffc) == PCI_CLASS_REVISION)
 		/*
 		 * RC's class is 0xb, but Linux PCI driver needs 0x604
 		 * for a PCIe bridge. So we must fixup the class code
 		 * to 0x604 here.
 		 */
 		*val = ((((*val << shift) & 0xff) | (0x604 << 16)) >> shift) & mask;

 	return ret;
 }

 static int cns3xxx_pci_setup(int nr, struct pci_sys_data *sys)
 {
 	struct cns3xxx_pcie *cnspci = sysdata_to_cnspci(sys);
 	struct resource *res_io = &cnspci->res_io;
 	struct resource *res_mem = &cnspci->res_mem;

 	BUG_ON(request_resource(&iomem_resource, res_io) ||
 	       request_resource(&iomem_resource, res_mem));

 	pci_add_resource_offset(&sys->resources, res_io, sys->io_offset);
 	pci_add_resource_offset(&sys->resources, res_mem, sys->mem_offset);

 	return 1;
 }

 static struct pci_ops cns3xxx_pcie_ops = {
 	.map_bus = cns3xxx_pci_map_bus,
 	.read = cns3xxx_pci_read_config,
 	.write = pci_generic_config_write,
 };

 static int cns3xxx_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
 {
 	struct cns3xxx_pcie *cnspci = pdev_to_cnspci(dev);
 	int irq = cnspci->irqs[!!dev->bus->number];

 	pr_info("PCIe map irq: %04d:%02x:%02x.%02x slot %d, pin %d, irq: %d\n",
 		pci_domain_nr(dev->bus), dev->bus->number, PCI_SLOT(dev->devfn),
 		PCI_FUNC(dev->devfn), slot, pin, irq);

 	return irq;
 }

 static struct cns3xxx_pcie cns3xxx_pcie[] = {
 	[0] = {
 		.host_regs = (void __iomem *)CNS3XXX_PCIE0_HOST_BASE_VIRT,
 		.cfg0_regs = (void __iomem *)CNS3XXX_PCIE0_CFG0_BASE_VIRT,
 		.cfg1_regs = (void __iomem *)CNS3XXX_PCIE0_CFG1_BASE_VIRT,
 		.res_io = {
 			.name = "PCIe0 I/O space",
 			.start = CNS3XXX_PCIE0_IO_BASE,
 			.end = CNS3XXX_PCIE0_CFG0_BASE - 1, /* 16 MiB */
 			.flags = IORESOURCE_IO,
 		},
 		.res_mem = {
 			.name = "PCIe0 non-prefetchable",
 			.start = CNS3XXX_PCIE0_MEM_BASE,
 			.end = CNS3XXX_PCIE0_HOST_BASE - 1, /* 176 MiB */
 			.flags = IORESOURCE_MEM,
 		},
 		.irqs = { IRQ_CNS3XXX_PCIE0_RC, IRQ_CNS3XXX_PCIE0_DEVICE, },
 		.port = 0,
 	},
 	[1] = {
 		.host_regs = (void __iomem *)CNS3XXX_PCIE1_HOST_BASE_VIRT,
 		.cfg0_regs = (void __iomem *)CNS3XXX_PCIE1_CFG0_BASE_VIRT,
 		.cfg1_regs = (void __iomem *)CNS3XXX_PCIE1_CFG1_BASE_VIRT,
 		.res_io = {
 			.name = "PCIe1 I/O space",
 			.start = CNS3XXX_PCIE1_IO_BASE,
 			.end = CNS3XXX_PCIE1_CFG0_BASE - 1, /* 16 MiB */
 			.flags = IORESOURCE_IO,
 		},
 		.res_mem = {
 			.name = "PCIe1 non-prefetchable",
 			.start = CNS3XXX_PCIE1_MEM_BASE,
 			.end = CNS3XXX_PCIE1_HOST_BASE - 1, /* 176 MiB */
 			.flags = IORESOURCE_MEM,
 		},
 		.irqs = { IRQ_CNS3XXX_PCIE1_RC, IRQ_CNS3XXX_PCIE1_DEVICE, },
 		.port = 1,
 	},
 };

 static void __init cns3xxx_pcie_check_link(struct cns3xxx_pcie *cnspci)
 {
 	int port = cnspci->port;
 	u32 reg;
 	unsigned long time;

 	reg = __raw_readl(MISC_PCIE_CTRL(port));
 	/*
 	 * Enable Application Request to 1, it will exit L1 automatically,
 	 * but when chip back, it will use another clock, still can use 0x1.
 	 */
 	reg |= 0x3;
 	__raw_writel(reg, MISC_PCIE_CTRL(port));

 	pr_info("PCIe: Port[%d] Enable PCIe LTSSM\n", port);
 	pr_info("PCIe: Port[%d] Check data link layer...", port);

 	time = jiffies;
 	while (1) {
 		reg = __raw_readl(MISC_PCIE_PM_DEBUG(port));
 		if (reg & 0x1) {
 			pr_info("Link up.\n");
 			cnspci->linked = 1;
 			break;
 		} else if (time_after(jiffies, time + 50)) {
 			pr_info("Device not found.\n");
 			break;
 		}
 	}
 }

 static void cns3xxx_write_config(struct cns3xxx_pcie *cnspci,
 					 int where, int size, u32 val)
 {
 	void __iomem *base = cnspci->host_regs + (where & 0xffc);
 	u32 v;
 	u32 mask = (0x1ull << (size * 8)) - 1;
 	int shift = (where % 4) * 8;

 	v = readl_relaxed(base);

 	v &= ~(mask << shift);
 	v |= (val & mask) << shift;

 	writel_relaxed(v, base);
 	readl_relaxed(base);
 }

 static void __init cns3xxx_pcie_hw_init(struct cns3xxx_pcie *cnspci)
 {
 	u16 mem_base  = cnspci->res_mem.start >> 16;
 	u16 mem_limit = cnspci->res_mem.end   >> 16;
 	u16 io_base   = cnspci->res_io.start  >> 16;
 	u16 io_limit  = cnspci->res_io.end    >> 16;

 	cns3xxx_write_config(cnspci, PCI_PRIMARY_BUS, 1, 0);
 	cns3xxx_write_config(cnspci, PCI_SECONDARY_BUS, 1, 1);
 	cns3xxx_write_config(cnspci, PCI_SUBORDINATE_BUS, 1, 1);
 	cns3xxx_write_config(cnspci, PCI_MEMORY_BASE, 2, mem_base);
 	cns3xxx_write_config(cnspci, PCI_MEMORY_LIMIT, 2, mem_limit);
 	cns3xxx_write_config(cnspci, PCI_IO_BASE_UPPER16, 2, io_base);
 	cns3xxx_write_config(cnspci, PCI_IO_LIMIT_UPPER16, 2, io_limit);

 	if (!cnspci->linked)
 		return;

 	/* Set Device Max_Read_Request_Size to 128 byte */
 	pcie_bus_config = PCIE_BUS_PEER2PEER;

 	/* Disable PCIe0 Interrupt Mask INTA to INTD */
 	__raw_writel(~0x3FFF, MISC_PCIE_INT_MASK(cnspci->port));
 }

 static int cns3xxx_pcie_abort_handler(unsigned long addr, unsigned int fsr,
 				      struct pt_regs *regs)
 {
 	if (fsr & (1 << 10))
 		regs->ARM_pc += 4;
 	return 0;
 }

 void __init cns3xxx_pcie_init_late(void)
 {
 	int i;
 	void *private_data;
 	struct hw_pci hw_pci = {
 	       .nr_controllers = 1,
 	       .ops = &cns3xxx_pcie_ops,
 	       .setup = cns3xxx_pci_setup,
 	       .map_irq = cns3xxx_pcie_map_irq,
 	       .private_data = &private_data,
 	};

 	pcibios_min_io = 0;
 	pcibios_min_mem = 0;

 	hook_fault_code(16 + 6, cns3xxx_pcie_abort_handler, SIGBUS, 0,
 			"imprecise external abort");

 	for (i = 0; i < ARRAY_SIZE(cns3xxx_pcie); i++) {
 		cns3xxx_pwr_clk_en(0x1 << PM_CLK_GATE_REG_OFFSET_PCIE(i));
 		cns3xxx_pwr_soft_rst(0x1 << PM_SOFT_RST_REG_OFFST_PCIE(i));
 		cns3xxx_pcie_check_link(&cns3xxx_pcie[i]);
 		cns3xxx_pcie_hw_init(&cns3xxx_pcie[i]);
 		private_data = &cns3xxx_pcie[i];
 		pci_common_init(&hw_pci);
 	}

 	pci_assign_unassigned_resources();
 }
	/*
	* PCI-E support for CNS3xxx
	*
	* Copyright 2008 Cavium Networks
	* Richard Liu <richard.liu@caviumnetworks.com>
	* Copyright 2010 MontaVista Software, LLC.
	* Anton Vorontsov <avorontsov@mvista.com>
	*
	* This file is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License, Version 2, as
	* published by the Free Software Foundation.
	*/

	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/bug.h>
	#include <linux/pci.h>
	#include <linux/io.h>
	#include <linux/ioport.h>
	#include <linux/interrupt.h>
	#include <linux/ptrace.h>
	#include <asm/mach/map.h>
	#include "cns3xxx.h"
	#include "core.h"

	struct cns3xxx_pcie {
	void __iomem host_regs; / PCI config registers for host bridge */
	void __iomem cfg0_regs; / PCI Type 0 config registers */
	void __iomem cfg1_regs; / PCI Type 1 config registers */
	unsigned int irqs[2];
	struct resource res_io;
	struct resource res_mem;
	int port;
	bool linked;
	};

	static struct cns3xxx_pcie sysdata_to_cnspci(void sysdata)
	{
	struct pci_sys_data *root = sysdata;

	return root->private_data;
	}

	static struct cns3xxx_pcie pdev_to_cnspci(const struct pci_dev dev)
	{
	return sysdata_to_cnspci(dev->sysdata);
	}

	static struct cns3xxx_pcie pbus_to_cnspci(struct pci_bus bus)
	{
	return sysdata_to_cnspci(bus->sysdata);
	}

	static void __iomem cns3xxx_pci_map_bus(struct pci_bus bus,
	unsigned int devfn, int where)
	{
	struct cns3xxx_pcie *cnspci = pbus_to_cnspci(bus);
	int busno = bus->number;
	int slot = PCI_SLOT(devfn);
	void __iomem *base;

	/* If there is no link, just show the CNS PCI bridge. */
	if (!cnspci->linked && busno > 0)
	return NULL;

	/*
	* The CNS PCI bridge doesn't fit into the PCI hierarchy, though
	* we still want to access it.
	* We place the host bridge on bus 0, and the directly connected
	* device on bus 1, slot 0.
	*/
	if (busno == 0) { /* internal PCIe bus, host bridge device */
	if (devfn == 0) /* device# and function# are ignored by hw */
	base = cnspci->host_regs;
	else
	return NULL; /* no such device */

	} else if (busno == 1) { /* directly connected PCIe device */
	if (slot == 0) /* device# is ignored by hw */
	base = cnspci->cfg0_regs;
	else
	return NULL; /* no such device */
	} else /* remote PCI bus */
	base = cnspci->cfg1_regs + ((busno & 0xf) << 20);

	return base + (where & 0xffc) + (devfn << 12);
	}

	static int cns3xxx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
	int where, int size, u32 *val)
	{
	int ret;
	u32 mask = (0x1ull << (size * 8)) - 1;
	int shift = (where % 4) * 8;

	ret = pci_generic_config_read32(bus, devfn, where, size, val);

	if (ret == PCIBIOS_SUCCESSFUL && !bus->number && !devfn &&
	(where & 0xffc) == PCI_CLASS_REVISION)
	/*
	* RC's class is 0xb, but Linux PCI driver needs 0x604
	* for a PCIe bridge. So we must fixup the class code
	* to 0x604 here.
	*/
	val = ((((val << shift) & 0xff) \| (0x604 << 16)) >> shift) & mask;

	return ret;
	}

	static int cns3xxx_pci_setup(int nr, struct pci_sys_data *sys)
	{
	struct cns3xxx_pcie *cnspci = sysdata_to_cnspci(sys);
	struct resource *res_io = &cnspci->res_io;
	struct resource *res_mem = &cnspci->res_mem;

	BUG_ON(request_resource(&iomem_resource, res_io) \|\|
	request_resource(&iomem_resource, res_mem));

	pci_add_resource_offset(&sys->resources, res_io, sys->io_offset);
	pci_add_resource_offset(&sys->resources, res_mem, sys->mem_offset);

	return 1;
	}

	static struct pci_ops cns3xxx_pcie_ops = {
	.map_bus = cns3xxx_pci_map_bus,
	.read = cns3xxx_pci_read_config,
	.write = pci_generic_config_write,
	};

	static int cns3xxx_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
	{
	struct cns3xxx_pcie *cnspci = pdev_to_cnspci(dev);
	int irq = cnspci->irqs[!!dev->bus->number];

	pr_info("PCIe map irq: %04d:%02x:%02x.%02x slot %d, pin %d, irq: %d\n",
	pci_domain_nr(dev->bus), dev->bus->number, PCI_SLOT(dev->devfn),
	PCI_FUNC(dev->devfn), slot, pin, irq);

	return irq;
	}

	static struct cns3xxx_pcie cns3xxx_pcie[] = {
	[0] = {
	.host_regs = (void __iomem *)CNS3XXX_PCIE0_HOST_BASE_VIRT,
	.cfg0_regs = (void __iomem *)CNS3XXX_PCIE0_CFG0_BASE_VIRT,
	.cfg1_regs = (void __iomem *)CNS3XXX_PCIE0_CFG1_BASE_VIRT,
	.res_io = {
	.name = "PCIe0 I/O space",
	.start = CNS3XXX_PCIE0_IO_BASE,
	.end = CNS3XXX_PCIE0_CFG0_BASE - 1, /* 16 MiB */
	.flags = IORESOURCE_IO,
	},
	.res_mem = {
	.name = "PCIe0 non-prefetchable",
	.start = CNS3XXX_PCIE0_MEM_BASE,
	.end = CNS3XXX_PCIE0_HOST_BASE - 1, /* 176 MiB */
	.flags = IORESOURCE_MEM,
	},
	.irqs = { IRQ_CNS3XXX_PCIE0_RC, IRQ_CNS3XXX_PCIE0_DEVICE, },
	.port = 0,
	},
	[1] = {
	.host_regs = (void __iomem *)CNS3XXX_PCIE1_HOST_BASE_VIRT,
	.cfg0_regs = (void __iomem *)CNS3XXX_PCIE1_CFG0_BASE_VIRT,
	.cfg1_regs = (void __iomem *)CNS3XXX_PCIE1_CFG1_BASE_VIRT,
	.res_io = {
	.name = "PCIe1 I/O space",
	.start = CNS3XXX_PCIE1_IO_BASE,
	.end = CNS3XXX_PCIE1_CFG0_BASE - 1, /* 16 MiB */
	.flags = IORESOURCE_IO,
	},
	.res_mem = {
	.name = "PCIe1 non-prefetchable",
	.start = CNS3XXX_PCIE1_MEM_BASE,
	.end = CNS3XXX_PCIE1_HOST_BASE - 1, /* 176 MiB */
	.flags = IORESOURCE_MEM,
	},
	.irqs = { IRQ_CNS3XXX_PCIE1_RC, IRQ_CNS3XXX_PCIE1_DEVICE, },
	.port = 1,
	},
	};

	static void __init cns3xxx_pcie_check_link(struct cns3xxx_pcie *cnspci)
	{
	int port = cnspci->port;
	u32 reg;
	unsigned long time;

	reg = __raw_readl(MISC_PCIE_CTRL(port));
	/*
	* Enable Application Request to 1, it will exit L1 automatically,
	* but when chip back, it will use another clock, still can use 0x1.
	*/
	reg \|= 0x3;
	__raw_writel(reg, MISC_PCIE_CTRL(port));

	pr_info("PCIe: Port[%d] Enable PCIe LTSSM\n", port);
	pr_info("PCIe: Port[%d] Check data link layer...", port);

	time = jiffies;
	while (1) {
	reg = __raw_readl(MISC_PCIE_PM_DEBUG(port));
	if (reg & 0x1) {
	pr_info("Link up.\n");
	cnspci->linked = 1;
	break;
	} else if (time_after(jiffies, time + 50)) {
	pr_info("Device not found.\n");
	break;
	}
	}
	}

	static void cns3xxx_write_config(struct cns3xxx_pcie *cnspci,
	int where, int size, u32 val)
	{
	void __iomem *base = cnspci->host_regs + (where & 0xffc);
	u32 v;
	u32 mask = (0x1ull << (size * 8)) - 1;
	int shift = (where % 4) * 8;

	v = readl_relaxed(base);

	v &= ~(mask << shift);
	v \|= (val & mask) << shift;

	writel_relaxed(v, base);
	readl_relaxed(base);
	}

	static void __init cns3xxx_pcie_hw_init(struct cns3xxx_pcie *cnspci)
	{
	u16 mem_base = cnspci->res_mem.start >> 16;
	u16 mem_limit = cnspci->res_mem.end >> 16;
	u16 io_base = cnspci->res_io.start >> 16;
	u16 io_limit = cnspci->res_io.end >> 16;

	cns3xxx_write_config(cnspci, PCI_PRIMARY_BUS, 1, 0);
	cns3xxx_write_config(cnspci, PCI_SECONDARY_BUS, 1, 1);
	cns3xxx_write_config(cnspci, PCI_SUBORDINATE_BUS, 1, 1);
	cns3xxx_write_config(cnspci, PCI_MEMORY_BASE, 2, mem_base);
	cns3xxx_write_config(cnspci, PCI_MEMORY_LIMIT, 2, mem_limit);
	cns3xxx_write_config(cnspci, PCI_IO_BASE_UPPER16, 2, io_base);
	cns3xxx_write_config(cnspci, PCI_IO_LIMIT_UPPER16, 2, io_limit);

	if (!cnspci->linked)
	return;

	/* Set Device Max_Read_Request_Size to 128 byte */
	pcie_bus_config = PCIE_BUS_PEER2PEER;

	/* Disable PCIe0 Interrupt Mask INTA to INTD */
	__raw_writel(~0x3FFF, MISC_PCIE_INT_MASK(cnspci->port));
	}

	static int cns3xxx_pcie_abort_handler(unsigned long addr, unsigned int fsr,
	struct pt_regs *regs)
	{
	if (fsr & (1 << 10))
	regs->ARM_pc += 4;
	return 0;
	}

	void __init cns3xxx_pcie_init_late(void)
	{
	int i;
	void *private_data;
	struct hw_pci hw_pci = {
	.nr_controllers = 1,
	.ops = &cns3xxx_pcie_ops,
	.setup = cns3xxx_pci_setup,
	.map_irq = cns3xxx_pcie_map_irq,
	.private_data = &private_data,
	};

	pcibios_min_io = 0;
	pcibios_min_mem = 0;

	hook_fault_code(16 + 6, cns3xxx_pcie_abort_handler, SIGBUS, 0,
	"imprecise external abort");

	for (i = 0; i < ARRAY_SIZE(cns3xxx_pcie); i++) {
	cns3xxx_pwr_clk_en(0x1 << PM_CLK_GATE_REG_OFFSET_PCIE(i));
	cns3xxx_pwr_soft_rst(0x1 << PM_SOFT_RST_REG_OFFST_PCIE(i));
	cns3xxx_pcie_check_link(&cns3xxx_pcie[i]);
	cns3xxx_pcie_hw_init(&cns3xxx_pcie[i]);
	private_data = &cns3xxx_pcie[i];
	pci_common_init(&hw_pci);
	}

	pci_assign_unassigned_resources();
	}