linux/arch/mips/pci/pci-lantiq.c
John Crispin e47d488935 MIPS: Lantiq: Add PCI controller support.
The Lantiq family of SoCs have a EBU (External Bus Unit). This patch adds
the driver that allows us to use the EBU as a PCI controller. In order for
PCI to work the EBU is set to endianess swap all the data. In addition we
need to make use of SWAP_IO_SPACE for device->host DMA to work.

The clock of the PCI works in several modes (internal/external). If this
is not configured correctly the SoC will hang.

Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Ralph Hempel <ralph.hempel@lantiq.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2250/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-05-19 09:55:42 +01:00

298 lines
8.2 KiB
C

/*
* This program 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.
*
* Copyright (C) 2010 John Crispin <blogic@openwrt.org>
*/
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/platform_device.h>
#include <asm/pci.h>
#include <asm/gpio.h>
#include <asm/addrspace.h>
#include <lantiq_soc.h>
#include <lantiq_irq.h>
#include <lantiq_platform.h>
#include "pci-lantiq.h"
#define LTQ_PCI_CFG_BASE 0x17000000
#define LTQ_PCI_CFG_SIZE 0x00008000
#define LTQ_PCI_MEM_BASE 0x18000000
#define LTQ_PCI_MEM_SIZE 0x02000000
#define LTQ_PCI_IO_BASE 0x1AE00000
#define LTQ_PCI_IO_SIZE 0x00200000
#define PCI_CR_FCI_ADDR_MAP0 0x00C0
#define PCI_CR_FCI_ADDR_MAP1 0x00C4
#define PCI_CR_FCI_ADDR_MAP2 0x00C8
#define PCI_CR_FCI_ADDR_MAP3 0x00CC
#define PCI_CR_FCI_ADDR_MAP4 0x00D0
#define PCI_CR_FCI_ADDR_MAP5 0x00D4
#define PCI_CR_FCI_ADDR_MAP6 0x00D8
#define PCI_CR_FCI_ADDR_MAP7 0x00DC
#define PCI_CR_CLK_CTRL 0x0000
#define PCI_CR_PCI_MOD 0x0030
#define PCI_CR_PC_ARB 0x0080
#define PCI_CR_FCI_ADDR_MAP11hg 0x00E4
#define PCI_CR_BAR11MASK 0x0044
#define PCI_CR_BAR12MASK 0x0048
#define PCI_CR_BAR13MASK 0x004C
#define PCI_CS_BASE_ADDR1 0x0010
#define PCI_CR_PCI_ADDR_MAP11 0x0064
#define PCI_CR_FCI_BURST_LENGTH 0x00E8
#define PCI_CR_PCI_EOI 0x002C
#define PCI_CS_STS_CMD 0x0004
#define PCI_MASTER0_REQ_MASK_2BITS 8
#define PCI_MASTER1_REQ_MASK_2BITS 10
#define PCI_MASTER2_REQ_MASK_2BITS 12
#define INTERNAL_ARB_ENABLE_BIT 0
#define LTQ_CGU_IFCCR 0x0018
#define LTQ_CGU_PCICR 0x0034
#define ltq_pci_w32(x, y) ltq_w32((x), ltq_pci_membase + (y))
#define ltq_pci_r32(x) ltq_r32(ltq_pci_membase + (x))
#define ltq_pci_cfg_w32(x, y) ltq_w32((x), ltq_pci_mapped_cfg + (y))
#define ltq_pci_cfg_r32(x) ltq_r32(ltq_pci_mapped_cfg + (x))
struct ltq_pci_gpio_map {
int pin;
int alt0;
int alt1;
int dir;
char *name;
};
/* the pci core can make use of the following gpios */
static struct ltq_pci_gpio_map ltq_pci_gpio_map[] = {
{ 0, 1, 0, 0, "pci-exin0" },
{ 1, 1, 0, 0, "pci-exin1" },
{ 2, 1, 0, 0, "pci-exin2" },
{ 39, 1, 0, 0, "pci-exin3" },
{ 10, 1, 0, 0, "pci-exin4" },
{ 9, 1, 0, 0, "pci-exin5" },
{ 30, 1, 0, 1, "pci-gnt1" },
{ 23, 1, 0, 1, "pci-gnt2" },
{ 19, 1, 0, 1, "pci-gnt3" },
{ 38, 1, 0, 1, "pci-gnt4" },
{ 29, 1, 0, 0, "pci-req1" },
{ 31, 1, 0, 0, "pci-req2" },
{ 3, 1, 0, 0, "pci-req3" },
{ 37, 1, 0, 0, "pci-req4" },
};
__iomem void *ltq_pci_mapped_cfg;
static __iomem void *ltq_pci_membase;
int (*ltqpci_plat_dev_init)(struct pci_dev *dev) = NULL;
/* Since the PCI REQ pins can be reused for other functionality, make it
possible to exclude those from interpretation by the PCI controller */
static int ltq_pci_req_mask = 0xf;
static int *ltq_pci_irq_map;
struct pci_ops ltq_pci_ops = {
.read = ltq_pci_read_config_dword,
.write = ltq_pci_write_config_dword
};
static struct resource pci_io_resource = {
.name = "pci io space",
.start = LTQ_PCI_IO_BASE,
.end = LTQ_PCI_IO_BASE + LTQ_PCI_IO_SIZE - 1,
.flags = IORESOURCE_IO
};
static struct resource pci_mem_resource = {
.name = "pci memory space",
.start = LTQ_PCI_MEM_BASE,
.end = LTQ_PCI_MEM_BASE + LTQ_PCI_MEM_SIZE - 1,
.flags = IORESOURCE_MEM
};
static struct pci_controller ltq_pci_controller = {
.pci_ops = &ltq_pci_ops,
.mem_resource = &pci_mem_resource,
.mem_offset = 0x00000000UL,
.io_resource = &pci_io_resource,
.io_offset = 0x00000000UL,
};
int pcibios_plat_dev_init(struct pci_dev *dev)
{
if (ltqpci_plat_dev_init)
return ltqpci_plat_dev_init(dev);
return 0;
}
static u32 ltq_calc_bar11mask(void)
{
u32 mem, bar11mask;
/* BAR11MASK value depends on available memory on system. */
mem = num_physpages * PAGE_SIZE;
bar11mask = (0x0ffffff0 & ~((1 << (fls(mem) - 1)) - 1)) | 8;
return bar11mask;
}
static void ltq_pci_setup_gpio(int gpio)
{
int i;
for (i = 0; i < ARRAY_SIZE(ltq_pci_gpio_map); i++) {
if (gpio & (1 << i)) {
ltq_gpio_request(ltq_pci_gpio_map[i].pin,
ltq_pci_gpio_map[i].alt0,
ltq_pci_gpio_map[i].alt1,
ltq_pci_gpio_map[i].dir,
ltq_pci_gpio_map[i].name);
}
}
ltq_gpio_request(21, 0, 0, 1, "pci-reset");
ltq_pci_req_mask = (gpio >> PCI_REQ_SHIFT) & PCI_REQ_MASK;
}
static int __devinit ltq_pci_startup(struct ltq_pci_data *conf)
{
u32 temp_buffer;
/* set clock to 33Mhz */
ltq_cgu_w32(ltq_cgu_r32(LTQ_CGU_IFCCR) & ~0xf00000, LTQ_CGU_IFCCR);
ltq_cgu_w32(ltq_cgu_r32(LTQ_CGU_IFCCR) | 0x800000, LTQ_CGU_IFCCR);
/* external or internal clock ? */
if (conf->clock) {
ltq_cgu_w32(ltq_cgu_r32(LTQ_CGU_IFCCR) & ~(1 << 16),
LTQ_CGU_IFCCR);
ltq_cgu_w32((1 << 30), LTQ_CGU_PCICR);
} else {
ltq_cgu_w32(ltq_cgu_r32(LTQ_CGU_IFCCR) | (1 << 16),
LTQ_CGU_IFCCR);
ltq_cgu_w32((1 << 31) | (1 << 30), LTQ_CGU_PCICR);
}
/* setup pci clock and gpis used by pci */
ltq_pci_setup_gpio(conf->gpio);
/* enable auto-switching between PCI and EBU */
ltq_pci_w32(0xa, PCI_CR_CLK_CTRL);
/* busy, i.e. configuration is not done, PCI access has to be retried */
ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_MOD) & ~(1 << 24), PCI_CR_PCI_MOD);
wmb();
/* BUS Master/IO/MEM access */
ltq_pci_cfg_w32(ltq_pci_cfg_r32(PCI_CS_STS_CMD) | 7, PCI_CS_STS_CMD);
/* enable external 2 PCI masters */
temp_buffer = ltq_pci_r32(PCI_CR_PC_ARB);
temp_buffer &= (~(ltq_pci_req_mask << 16));
/* enable internal arbiter */
temp_buffer |= (1 << INTERNAL_ARB_ENABLE_BIT);
/* enable internal PCI master reqest */
temp_buffer &= (~(3 << PCI_MASTER0_REQ_MASK_2BITS));
/* enable EBU request */
temp_buffer &= (~(3 << PCI_MASTER1_REQ_MASK_2BITS));
/* enable all external masters request */
temp_buffer &= (~(3 << PCI_MASTER2_REQ_MASK_2BITS));
ltq_pci_w32(temp_buffer, PCI_CR_PC_ARB);
wmb();
/* setup BAR memory regions */
ltq_pci_w32(0x18000000, PCI_CR_FCI_ADDR_MAP0);
ltq_pci_w32(0x18400000, PCI_CR_FCI_ADDR_MAP1);
ltq_pci_w32(0x18800000, PCI_CR_FCI_ADDR_MAP2);
ltq_pci_w32(0x18c00000, PCI_CR_FCI_ADDR_MAP3);
ltq_pci_w32(0x19000000, PCI_CR_FCI_ADDR_MAP4);
ltq_pci_w32(0x19400000, PCI_CR_FCI_ADDR_MAP5);
ltq_pci_w32(0x19800000, PCI_CR_FCI_ADDR_MAP6);
ltq_pci_w32(0x19c00000, PCI_CR_FCI_ADDR_MAP7);
ltq_pci_w32(0x1ae00000, PCI_CR_FCI_ADDR_MAP11hg);
ltq_pci_w32(ltq_calc_bar11mask(), PCI_CR_BAR11MASK);
ltq_pci_w32(0, PCI_CR_PCI_ADDR_MAP11);
ltq_pci_w32(0, PCI_CS_BASE_ADDR1);
/* both TX and RX endian swap are enabled */
ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_EOI) | 3, PCI_CR_PCI_EOI);
wmb();
ltq_pci_w32(ltq_pci_r32(PCI_CR_BAR12MASK) | 0x80000000,
PCI_CR_BAR12MASK);
ltq_pci_w32(ltq_pci_r32(PCI_CR_BAR13MASK) | 0x80000000,
PCI_CR_BAR13MASK);
/*use 8 dw burst length */
ltq_pci_w32(0x303, PCI_CR_FCI_BURST_LENGTH);
ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_MOD) | (1 << 24), PCI_CR_PCI_MOD);
wmb();
/* setup irq line */
ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_CON) | 0xc, LTQ_EBU_PCC_CON);
ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_IEN) | 0x10, LTQ_EBU_PCC_IEN);
/* toggle reset pin */
__gpio_set_value(21, 0);
wmb();
mdelay(1);
__gpio_set_value(21, 1);
return 0;
}
int __init pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
if (ltq_pci_irq_map[slot])
return ltq_pci_irq_map[slot];
printk(KERN_ERR "lq_pci: trying to map irq for unknown slot %d\n",
slot);
return 0;
}
static int __devinit ltq_pci_probe(struct platform_device *pdev)
{
struct ltq_pci_data *ltq_pci_data =
(struct ltq_pci_data *) pdev->dev.platform_data;
pci_probe_only = 0;
ltq_pci_irq_map = ltq_pci_data->irq;
ltq_pci_membase = ioremap_nocache(PCI_CR_BASE_ADDR, PCI_CR_SIZE);
ltq_pci_mapped_cfg =
ioremap_nocache(LTQ_PCI_CFG_BASE, LTQ_PCI_CFG_BASE);
ltq_pci_controller.io_map_base =
(unsigned long)ioremap(LTQ_PCI_IO_BASE, LTQ_PCI_IO_SIZE - 1);
ltq_pci_startup(ltq_pci_data);
register_pci_controller(&ltq_pci_controller);
return 0;
}
static struct platform_driver
ltq_pci_driver = {
.probe = ltq_pci_probe,
.driver = {
.name = "ltq_pci",
.owner = THIS_MODULE,
},
};
int __init pcibios_init(void)
{
int ret = platform_driver_register(&ltq_pci_driver);
if (ret)
printk(KERN_INFO "ltq_pci: Error registering platfom driver!");
return ret;
}
arch_initcall(pcibios_init);