/*
* 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();
}
