https://github.com/torvalds/linux
Tip revision: a38297e3fb012ddfa7ce0321a7e5a8daeb1872b6 authored by Linus Torvalds on 12 May 2024, 21:12:29 UTC
Linux 6.9
Linux 6.9
Tip revision: a38297e
pci-mt7620.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Ralink MT7620A SoC PCI support
*
* Copyright (C) 2007-2013 Bruce Chang (Mediatek)
* Copyright (C) 2013-2016 John Crispin <john@phrozen.org>
*/
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/io.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_pci.h>
#include <linux/reset.h>
#include <linux/platform_device.h>
#include <asm/mach-ralink/ralink_regs.h>
#include <asm/mach-ralink/mt7620.h>
#define RALINK_PCI_IO_MAP_BASE 0x10160000
#define RALINK_PCI_MEMORY_BASE 0x0
#define RALINK_INT_PCIE0 4
#define RALINK_CLKCFG1 0x30
#define RALINK_GPIOMODE 0x60
#define PPLL_CFG1 0x9c
#define PPLL_LD BIT(23)
#define PPLL_DRV 0xa0
#define PDRV_SW_SET BIT(31)
#define LC_CKDRVPD BIT(19)
#define LC_CKDRVOHZ BIT(18)
#define LC_CKDRVHZ BIT(17)
#define LC_CKTEST BIT(16)
/* PCI Bridge registers */
#define RALINK_PCI_PCICFG_ADDR 0x00
#define PCIRST BIT(1)
#define RALINK_PCI_PCIENA 0x0C
#define PCIINT2 BIT(20)
#define RALINK_PCI_CONFIG_ADDR 0x20
#define RALINK_PCI_CONFIG_DATA_VIRT_REG 0x24
#define RALINK_PCI_MEMBASE 0x28
#define RALINK_PCI_IOBASE 0x2C
/* PCI RC registers */
#define RALINK_PCI0_BAR0SETUP_ADDR 0x10
#define RALINK_PCI0_IMBASEBAR0_ADDR 0x18
#define RALINK_PCI0_ID 0x30
#define RALINK_PCI0_CLASS 0x34
#define RALINK_PCI0_SUBID 0x38
#define RALINK_PCI0_STATUS 0x50
#define PCIE_LINK_UP_ST BIT(0)
#define PCIEPHY0_CFG 0x90
#define RALINK_PCIEPHY_P0_CTL_OFFSET 0x7498
#define RALINK_PCIE0_CLK_EN BIT(26)
#define BUSY 0x80000000
#define WAITRETRY_MAX 10
#define WRITE_MODE (1UL << 23)
#define DATA_SHIFT 0
#define ADDR_SHIFT 8
static void __iomem *bridge_base;
static void __iomem *pcie_base;
static struct reset_control *rstpcie0;
static inline void bridge_w32(u32 val, unsigned reg)
{
iowrite32(val, bridge_base + reg);
}
static inline u32 bridge_r32(unsigned reg)
{
return ioread32(bridge_base + reg);
}
static inline void pcie_w32(u32 val, unsigned reg)
{
iowrite32(val, pcie_base + reg);
}
static inline u32 pcie_r32(unsigned reg)
{
return ioread32(pcie_base + reg);
}
static inline void pcie_m32(u32 clr, u32 set, unsigned reg)
{
u32 val = pcie_r32(reg);
val &= ~clr;
val |= set;
pcie_w32(val, reg);
}
static int wait_pciephy_busy(void)
{
unsigned long reg_value = 0x0, retry = 0;
while (1) {
reg_value = pcie_r32(PCIEPHY0_CFG);
if (reg_value & BUSY)
mdelay(100);
else
break;
if (retry++ > WAITRETRY_MAX) {
pr_warn("PCIE-PHY retry failed.\n");
return -1;
}
}
return 0;
}
static void pcie_phy(unsigned long addr, unsigned long val)
{
wait_pciephy_busy();
pcie_w32(WRITE_MODE | (val << DATA_SHIFT) | (addr << ADDR_SHIFT),
PCIEPHY0_CFG);
mdelay(1);
wait_pciephy_busy();
}
static int pci_config_read(struct pci_bus *bus, unsigned int devfn, int where,
int size, u32 *val)
{
unsigned int slot = PCI_SLOT(devfn);
u8 func = PCI_FUNC(devfn);
u32 address;
u32 data;
u32 num = 0;
if (bus)
num = bus->number;
address = (((where & 0xF00) >> 8) << 24) | (num << 16) | (slot << 11) |
(func << 8) | (where & 0xfc) | 0x80000000;
bridge_w32(address, RALINK_PCI_CONFIG_ADDR);
data = bridge_r32(RALINK_PCI_CONFIG_DATA_VIRT_REG);
switch (size) {
case 1:
*val = (data >> ((where & 3) << 3)) & 0xff;
break;
case 2:
*val = (data >> ((where & 3) << 3)) & 0xffff;
break;
case 4:
*val = data;
break;
}
return PCIBIOS_SUCCESSFUL;
}
static int pci_config_write(struct pci_bus *bus, unsigned int devfn, int where,
int size, u32 val)
{
unsigned int slot = PCI_SLOT(devfn);
u8 func = PCI_FUNC(devfn);
u32 address;
u32 data;
u32 num = 0;
if (bus)
num = bus->number;
address = (((where & 0xF00) >> 8) << 24) | (num << 16) | (slot << 11) |
(func << 8) | (where & 0xfc) | 0x80000000;
bridge_w32(address, RALINK_PCI_CONFIG_ADDR);
data = bridge_r32(RALINK_PCI_CONFIG_DATA_VIRT_REG);
switch (size) {
case 1:
data = (data & ~(0xff << ((where & 3) << 3))) |
(val << ((where & 3) << 3));
break;
case 2:
data = (data & ~(0xffff << ((where & 3) << 3))) |
(val << ((where & 3) << 3));
break;
case 4:
data = val;
break;
}
bridge_w32(data, RALINK_PCI_CONFIG_DATA_VIRT_REG);
return PCIBIOS_SUCCESSFUL;
}
struct pci_ops mt7620_pci_ops = {
.read = pci_config_read,
.write = pci_config_write,
};
static struct resource mt7620_res_pci_mem1;
static struct resource mt7620_res_pci_io1;
struct pci_controller mt7620_controller = {
.pci_ops = &mt7620_pci_ops,
.mem_resource = &mt7620_res_pci_mem1,
.mem_offset = 0x00000000UL,
.io_resource = &mt7620_res_pci_io1,
.io_offset = 0x00000000UL,
.io_map_base = 0xa0000000,
};
static int mt7620_pci_hw_init(struct platform_device *pdev)
{
/* bypass PCIe DLL */
pcie_phy(0x0, 0x80);
pcie_phy(0x1, 0x04);
/* Elastic buffer control */
pcie_phy(0x68, 0xB4);
/* put core into reset */
pcie_m32(0, PCIRST, RALINK_PCI_PCICFG_ADDR);
reset_control_assert(rstpcie0);
/* disable power and all clocks */
rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1);
rt_sysc_m32(LC_CKDRVPD, PDRV_SW_SET, PPLL_DRV);
/* bring core out of reset */
reset_control_deassert(rstpcie0);
rt_sysc_m32(0, RALINK_PCIE0_CLK_EN, RALINK_CLKCFG1);
mdelay(100);
if (!(rt_sysc_r32(PPLL_CFG1) & PPLL_LD)) {
dev_err(&pdev->dev, "pcie PLL not locked, aborting init\n");
reset_control_assert(rstpcie0);
rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1);
return -1;
}
/* power up the bus */
rt_sysc_m32(LC_CKDRVHZ | LC_CKDRVOHZ, LC_CKDRVPD | PDRV_SW_SET,
PPLL_DRV);
return 0;
}
static int mt7628_pci_hw_init(struct platform_device *pdev)
{
u32 val = 0;
/* bring the core out of reset */
rt_sysc_m32(BIT(16), 0, RALINK_GPIOMODE);
reset_control_deassert(rstpcie0);
/* enable the pci clk */
rt_sysc_m32(0, RALINK_PCIE0_CLK_EN, RALINK_CLKCFG1);
mdelay(100);
/* voodoo from the SDK driver */
pcie_m32(~0xff, 0x5, RALINK_PCIEPHY_P0_CTL_OFFSET);
pci_config_read(NULL, 0, 0x70c, 4, &val);
val &= ~(0xff) << 8;
val |= 0x50 << 8;
pci_config_write(NULL, 0, 0x70c, 4, val);
return 0;
}
static int mt7620_pci_probe(struct platform_device *pdev)
{
u32 val = 0;
rstpcie0 = devm_reset_control_get_exclusive(&pdev->dev, "pcie0");
if (IS_ERR(rstpcie0))
return PTR_ERR(rstpcie0);
bridge_base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
if (IS_ERR(bridge_base))
return PTR_ERR(bridge_base);
pcie_base = devm_platform_get_and_ioremap_resource(pdev, 1, NULL);
if (IS_ERR(pcie_base))
return PTR_ERR(pcie_base);
iomem_resource.start = 0;
iomem_resource.end = ~0;
ioport_resource.start = 0;
ioport_resource.end = ~0;
/* bring up the pci core */
switch (ralink_soc) {
case MT762X_SOC_MT7620A:
if (mt7620_pci_hw_init(pdev))
return -1;
break;
case MT762X_SOC_MT7628AN:
case MT762X_SOC_MT7688:
if (mt7628_pci_hw_init(pdev))
return -1;
break;
default:
dev_err(&pdev->dev, "pcie is not supported on this hardware\n");
return -1;
}
mdelay(50);
/* enable write access */
pcie_m32(PCIRST, 0, RALINK_PCI_PCICFG_ADDR);
mdelay(100);
/* check if there is a card present */
if ((pcie_r32(RALINK_PCI0_STATUS) & PCIE_LINK_UP_ST) == 0) {
reset_control_assert(rstpcie0);
rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1);
if (ralink_soc == MT762X_SOC_MT7620A)
rt_sysc_m32(LC_CKDRVPD, PDRV_SW_SET, PPLL_DRV);
dev_info(&pdev->dev, "PCIE0 no card, disable it(RST&CLK)\n");
return -1;
}
/* setup ranges */
bridge_w32(0xffffffff, RALINK_PCI_MEMBASE);
bridge_w32(RALINK_PCI_IO_MAP_BASE, RALINK_PCI_IOBASE);
pcie_w32(0x7FFF0001, RALINK_PCI0_BAR0SETUP_ADDR);
pcie_w32(RALINK_PCI_MEMORY_BASE, RALINK_PCI0_IMBASEBAR0_ADDR);
pcie_w32(0x06040001, RALINK_PCI0_CLASS);
/* enable interrupts */
pcie_m32(0, PCIINT2, RALINK_PCI_PCIENA);
/* voodoo from the SDK driver */
pci_config_read(NULL, 0, 4, 4, &val);
pci_config_write(NULL, 0, 4, 4, val | 0x7);
pci_load_of_ranges(&mt7620_controller, pdev->dev.of_node);
register_pci_controller(&mt7620_controller);
return 0;
}
int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
u16 cmd;
u32 val;
int irq = 0;
if ((dev->bus->number == 0) && (slot == 0)) {
pcie_w32(0x7FFF0001, RALINK_PCI0_BAR0SETUP_ADDR);
pci_config_write(dev->bus, 0, PCI_BASE_ADDRESS_0, 4,
RALINK_PCI_MEMORY_BASE);
pci_config_read(dev->bus, 0, PCI_BASE_ADDRESS_0, 4, &val);
} else if ((dev->bus->number == 1) && (slot == 0x0)) {
irq = RALINK_INT_PCIE0;
} else {
dev_err(&dev->dev, "no irq found - bus=0x%x, slot = 0x%x\n",
dev->bus->number, slot);
return 0;
}
dev_info(&dev->dev, "card - bus=0x%x, slot = 0x%x irq=%d\n",
dev->bus->number, slot, irq);
/* configure the cache line size to 0x14 */
pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, 0x14);
/* configure latency timer to 0xff */
pci_write_config_byte(dev, PCI_LATENCY_TIMER, 0xff);
pci_read_config_word(dev, PCI_COMMAND, &cmd);
/* setup the slot */
cmd = cmd | PCI_COMMAND_MASTER | PCI_COMMAND_IO | PCI_COMMAND_MEMORY;
pci_write_config_word(dev, PCI_COMMAND, cmd);
pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
return irq;
}
int pcibios_plat_dev_init(struct pci_dev *dev)
{
return 0;
}
static const struct of_device_id mt7620_pci_ids[] = {
{ .compatible = "mediatek,mt7620-pci" },
{},
};
static struct platform_driver mt7620_pci_driver = {
.probe = mt7620_pci_probe,
.driver = {
.name = "mt7620-pci",
.of_match_table = of_match_ptr(mt7620_pci_ids),
},
};
static int __init mt7620_pci_init(void)
{
return platform_driver_register(&mt7620_pci_driver);
}
arch_initcall(mt7620_pci_init);