/*
* 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 <mach/cns3xxx.h>
#include "core.h"
enum cns3xxx_access_type {
CNS3XXX_HOST_TYPE = 0,
CNS3XXX_CFG0_TYPE,
CNS3XXX_CFG1_TYPE,
CNS3XXX_NUM_ACCESS_TYPES,
};
struct cns3xxx_pcie {
struct map_desc cfg_bases[CNS3XXX_NUM_ACCESS_TYPES];
unsigned int irqs[2];
struct resource res_io;
struct resource res_mem;
struct hw_pci hw_pci;
bool linked;
};
static struct cns3xxx_pcie cns3xxx_pcie[]; /* forward decl. */
static struct cns3xxx_pcie *sysdata_to_cnspci(void *sysdata)
{
struct pci_sys_data *root = sysdata;
return &cns3xxx_pcie[root->domain];
}
static struct cns3xxx_pcie *pdev_to_cnspci(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_cfg_base(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);
int offset;
enum cns3xxx_access_type type;
void __iomem *base;
/* If there is no link, just show the CNS PCI bridge. */
if (!cnspci->linked && (busno > 0 || slot > 0))
return NULL;
/*
* The CNS PCI bridge doesn't fit into the PCI hierarchy, though
* we still want to access it. For this to work, we must place
* the first device on the same bus as the CNS PCI bridge.
*/
if (busno == 0) {
if (slot > 1)
return NULL;
type = slot;
} else {
type = CNS3XXX_CFG1_TYPE;
}
base = (void __iomem *)cnspci->cfg_bases[type].virtual;
offset = ((busno & 0xf) << 20) | (devfn << 12) | (where & 0xffc);
return base + offset;
}
static int cns3xxx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 *val)
{
u32 v;
void __iomem *base;
u32 mask = (0x1ull << (size * 8)) - 1;
int shift = (where % 4) * 8;
base = cns3xxx_pci_cfg_base(bus, devfn, where);
if (!base) {
*val = 0xffffffff;
return PCIBIOS_SUCCESSFUL;
}
v = __raw_readl(base);
if (bus->number == 0 && devfn == 0 &&
(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.
*/
v &= 0xff;
v |= 0x604 << 16;
}
*val = (v >> shift) & mask;
return PCIBIOS_SUCCESSFUL;
}
static int cns3xxx_pci_write_config(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 val)
{
u32 v;
void __iomem *base;
u32 mask = (0x1ull << (size * 8)) - 1;
int shift = (where % 4) * 8;
base = cns3xxx_pci_cfg_base(bus, devfn, where);
if (!base)
return PCIBIOS_SUCCESSFUL;
v = __raw_readl(base);
v &= ~(mask << shift);
v |= (val & mask) << shift;
__raw_writel(v, base);
return PCIBIOS_SUCCESSFUL;
}
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;
struct resource **sysres = sys->resource;
BUG_ON(request_resource(&iomem_resource, res_io) ||
request_resource(&iomem_resource, res_mem));
sysres[0] = res_io;
sysres[1] = res_mem;
return 1;
}
static struct pci_ops cns3xxx_pcie_ops = {
.read = cns3xxx_pci_read_config,
.write = cns3xxx_pci_write_config,
};
static struct pci_bus *cns3xxx_pci_scan_bus(int nr, struct pci_sys_data *sys)
{
return pci_scan_bus(sys->busnr, &cns3xxx_pcie_ops, sys);
}
static int cns3xxx_pcie_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
{
struct cns3xxx_pcie *cnspci = pdev_to_cnspci(dev);
int irq = cnspci->irqs[slot];
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] = {
.cfg_bases = {
[CNS3XXX_HOST_TYPE] = {
.virtual = CNS3XXX_PCIE0_HOST_BASE_VIRT,
.pfn = __phys_to_pfn(CNS3XXX_PCIE0_HOST_BASE),
.length = SZ_16M,
.type = MT_DEVICE,
},
[CNS3XXX_CFG0_TYPE] = {
.virtual = CNS3XXX_PCIE0_CFG0_BASE_VIRT,
.pfn = __phys_to_pfn(CNS3XXX_PCIE0_CFG0_BASE),
.length = SZ_16M,
.type = MT_DEVICE,
},
[CNS3XXX_CFG1_TYPE] = {
.virtual = CNS3XXX_PCIE0_CFG1_BASE_VIRT,
.pfn = __phys_to_pfn(CNS3XXX_PCIE0_CFG1_BASE),
.length = SZ_16M,
.type = MT_DEVICE,
},
},
.res_io = {
.name = "PCIe0 I/O space",
.start = CNS3XXX_PCIE0_IO_BASE,
.end = CNS3XXX_PCIE0_IO_BASE + SZ_16M - 1,
.flags = IORESOURCE_IO,
},
.res_mem = {
.name = "PCIe0 non-prefetchable",
.start = CNS3XXX_PCIE0_MEM_BASE,
.end = CNS3XXX_PCIE0_MEM_BASE + SZ_16M - 1,
.flags = IORESOURCE_MEM,
},
.irqs = { IRQ_CNS3XXX_PCIE0_RC, IRQ_CNS3XXX_PCIE0_DEVICE, },
.hw_pci = {
.domain = 0,
.swizzle = pci_std_swizzle,
.nr_controllers = 1,
.setup = cns3xxx_pci_setup,
.scan = cns3xxx_pci_scan_bus,
.map_irq = cns3xxx_pcie_map_irq,
},
},
[1] = {
.cfg_bases = {
[CNS3XXX_HOST_TYPE] = {
.virtual = CNS3XXX_PCIE1_HOST_BASE_VIRT,
.pfn = __phys_to_pfn(CNS3XXX_PCIE1_HOST_BASE),
.length = SZ_16M,
.type = MT_DEVICE,
},
[CNS3XXX_CFG0_TYPE] = {
.virtual = CNS3XXX_PCIE1_CFG0_BASE_VIRT,
.pfn = __phys_to_pfn(CNS3XXX_PCIE1_CFG0_BASE),
.length = SZ_16M,
.type = MT_DEVICE,
},
[CNS3XXX_CFG1_TYPE] = {
.virtual = CNS3XXX_PCIE1_CFG1_BASE_VIRT,
.pfn = __phys_to_pfn(CNS3XXX_PCIE1_CFG1_BASE),
.length = SZ_16M,
.type = MT_DEVICE,
},
},
.res_io = {
.name = "PCIe1 I/O space",
.start = CNS3XXX_PCIE1_IO_BASE,
.end = CNS3XXX_PCIE1_IO_BASE + SZ_16M - 1,
.flags = IORESOURCE_IO,
},
.res_mem = {
.name = "PCIe1 non-prefetchable",
.start = CNS3XXX_PCIE1_MEM_BASE,
.end = CNS3XXX_PCIE1_MEM_BASE + SZ_16M - 1,
.flags = IORESOURCE_MEM,
},
.irqs = { IRQ_CNS3XXX_PCIE1_RC, IRQ_CNS3XXX_PCIE1_DEVICE, },
.hw_pci = {
.domain = 1,
.swizzle = pci_std_swizzle,
.nr_controllers = 1,
.setup = cns3xxx_pci_setup,
.scan = cns3xxx_pci_scan_bus,
.map_irq = cns3xxx_pcie_map_irq,
},
},
};
static void __init cns3xxx_pcie_check_link(struct cns3xxx_pcie *cnspci)
{
int port = cnspci->hw_pci.domain;
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 __init cns3xxx_pcie_hw_init(struct cns3xxx_pcie *cnspci)
{
int port = cnspci->hw_pci.domain;
struct pci_sys_data sd = {
.domain = port,
};
struct pci_bus bus = {
.number = 0,
.ops = &cns3xxx_pcie_ops,
.sysdata = &sd,
};
u32 io_base = cnspci->res_io.start >> 16;
u32 mem_base = cnspci->res_mem.start >> 16;
u32 host_base = cnspci->cfg_bases[CNS3XXX_HOST_TYPE].pfn;
u32 cfg0_base = cnspci->cfg_bases[CNS3XXX_CFG0_TYPE].pfn;
u32 devfn = 0;
u8 tmp8;
u16 pos;
u16 dc;
host_base = (__pfn_to_phys(host_base) - 1) >> 16;
cfg0_base = (__pfn_to_phys(cfg0_base) - 1) >> 16;
pci_bus_write_config_byte(&bus, devfn, PCI_PRIMARY_BUS, 0);
pci_bus_write_config_byte(&bus, devfn, PCI_SECONDARY_BUS, 1);
pci_bus_write_config_byte(&bus, devfn, PCI_SUBORDINATE_BUS, 1);
pci_bus_read_config_byte(&bus, devfn, PCI_PRIMARY_BUS, &tmp8);
pci_bus_read_config_byte(&bus, devfn, PCI_SECONDARY_BUS, &tmp8);
pci_bus_read_config_byte(&bus, devfn, PCI_SUBORDINATE_BUS, &tmp8);
pci_bus_write_config_word(&bus, devfn, PCI_MEMORY_BASE, mem_base);
pci_bus_write_config_word(&bus, devfn, PCI_MEMORY_LIMIT, host_base);
pci_bus_write_config_word(&bus, devfn, PCI_IO_BASE_UPPER16, io_base);
pci_bus_write_config_word(&bus, devfn, PCI_IO_LIMIT_UPPER16, cfg0_base);
if (!cnspci->linked)
return;
/* Set Device Max_Read_Request_Size to 128 byte */
devfn = PCI_DEVFN(1, 0);
pos = pci_bus_find_capability(&bus, devfn, PCI_CAP_ID_EXP);
pci_bus_read_config_word(&bus, devfn, pos + PCI_EXP_DEVCTL, &dc);
dc &= ~(0x3 << 12); /* Clear Device Control Register [14:12] */
pci_bus_write_config_word(&bus, devfn, pos + PCI_EXP_DEVCTL, dc);
pci_bus_read_config_word(&bus, devfn, pos + PCI_EXP_DEVCTL, &dc);
if (!(dc & (0x3 << 12)))
pr_info("PCIe: Set Device Max_Read_Request_Size to 128 byte\n");
/* Disable PCIe0 Interrupt Mask INTA to INTD */
__raw_writel(~0x3FFF, MISC_PCIE_INT_MASK(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;
}
static int __init cns3xxx_pcie_init(void)
{
int i;
hook_fault_code(16 + 6, cns3xxx_pcie_abort_handler, SIGBUS,
"imprecise external abort");
for (i = 0; i < ARRAY_SIZE(cns3xxx_pcie); i++) {
iotable_init(cns3xxx_pcie[i].cfg_bases,
ARRAY_SIZE(cns3xxx_pcie[i].cfg_bases));
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]);
pci_common_init(&cns3xxx_pcie[i].hw_pci);
}
pci_assign_unassigned_resources();
return 0;
}
device_initcall(cns3xxx_pcie_init);
