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Nicolas Pitre authored
Commit 21f0ba90 "orion/kirkwood: reset PCIe unit on boot" made the reset of the PCIe unit unconditional. While this may fix problems on some targets, this also causes problems on other targets. Saeed Bishara <saeed@marvell.com> said about the original problem: "We couln't pinpoint the root cause of this issue, actually we failed to reproduce that issue." So let's restrict the reset of the PCIe unit only to the target where the original problem was observed. Signed-off-by:
Nicolas Pitre <nico@fluxnic.net>
3924996b
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pcie.c 7.16 KiB
/*
* arch/arm/plat-orion/pcie.c
*
* Marvell Orion SoC PCIe handling.
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/mbus.h>
#include <asm/mach/pci.h>
#include <plat/pcie.h>
#include <linux/delay.h>
/*
* PCIe unit register offsets.
*/
#define PCIE_DEV_ID_OFF 0x0000
#define PCIE_CMD_OFF 0x0004
#define PCIE_DEV_REV_OFF 0x0008
#define PCIE_BAR_LO_OFF(n) (0x0010 + ((n) << 3))
#define PCIE_BAR_HI_OFF(n) (0x0014 + ((n) << 3))
#define PCIE_HEADER_LOG_4_OFF 0x0128
#define PCIE_BAR_CTRL_OFF(n) (0x1804 + ((n - 1) * 4))
#define PCIE_WIN04_CTRL_OFF(n) (0x1820 + ((n) << 4))
#define PCIE_WIN04_BASE_OFF(n) (0x1824 + ((n) << 4))
#define PCIE_WIN04_REMAP_OFF(n) (0x182c + ((n) << 4))
#define PCIE_WIN5_CTRL_OFF 0x1880
#define PCIE_WIN5_BASE_OFF 0x1884
#define PCIE_WIN5_REMAP_OFF 0x188c
#define PCIE_CONF_ADDR_OFF 0x18f8
#define PCIE_CONF_ADDR_EN 0x80000000
#define PCIE_CONF_REG(r) ((((r) & 0xf00) << 16) | ((r) & 0xfc))
#define PCIE_CONF_BUS(b) (((b) & 0xff) << 16)
#define PCIE_CONF_DEV(d) (((d) & 0x1f) << 11)
#define PCIE_CONF_FUNC(f) (((f) & 0x7) << 8)
#define PCIE_CONF_DATA_OFF 0x18fc
#define PCIE_MASK_OFF 0x1910
#define PCIE_CTRL_OFF 0x1a00
#define PCIE_CTRL_X1_MODE 0x0001
#define PCIE_STAT_OFF 0x1a04
#define PCIE_STAT_DEV_OFFS 20
#define PCIE_STAT_DEV_MASK 0x1f
#define PCIE_STAT_BUS_OFFS 8
#define PCIE_STAT_BUS_MASK 0xff
#define PCIE_STAT_LINK_DOWN 1
#define PCIE_DEBUG_CTRL 0x1a60
#define PCIE_DEBUG_SOFT_RESET (1<<20)
u32 __init orion_pcie_dev_id(void __iomem *base)
{
return readl(base + PCIE_DEV_ID_OFF) >> 16;
}
u32 __init orion_pcie_rev(void __iomem *base)
{
return readl(base + PCIE_DEV_REV_OFF) & 0xff;
}
int orion_pcie_link_up(void __iomem *base)
{
return !(readl(base + PCIE_STAT_OFF) & PCIE_STAT_LINK_DOWN);
}
int __init orion_pcie_x4_mode(void __iomem *base)
{ return !(readl(base + PCIE_CTRL_OFF) & PCIE_CTRL_X1_MODE);
}
int orion_pcie_get_local_bus_nr(void __iomem *base)
{
u32 stat = readl(base + PCIE_STAT_OFF);
return (stat >> PCIE_STAT_BUS_OFFS) & PCIE_STAT_BUS_MASK;
}
void __init orion_pcie_set_local_bus_nr(void __iomem *base, int nr)
{
u32 stat;
stat = readl(base + PCIE_STAT_OFF);
stat &= ~(PCIE_STAT_BUS_MASK << PCIE_STAT_BUS_OFFS);
stat |= nr << PCIE_STAT_BUS_OFFS;
writel(stat, base + PCIE_STAT_OFF);
}
void __init orion_pcie_reset(void __iomem *base)
{
u32 reg;
int i;
/*
* MV-S104860-U0, Rev. C:
* PCI Express Unit Soft Reset
* When set, generates an internal reset in the PCI Express unit.
* This bit should be cleared after the link is re-established.
*/
reg = readl(base + PCIE_DEBUG_CTRL);
reg |= PCIE_DEBUG_SOFT_RESET;
writel(reg, base + PCIE_DEBUG_CTRL);
for (i = 0; i < 20; i++) {
mdelay(10);
if (orion_pcie_link_up(base))
break;
}
reg &= ~(PCIE_DEBUG_SOFT_RESET);
writel(reg, base + PCIE_DEBUG_CTRL);
}
/*
* Setup PCIE BARs and Address Decode Wins:
* BAR[0,2] -> disabled, BAR[1] -> covers all DRAM banks
* WIN[0-3] -> DRAM bank[0-3]
*/
static void __init orion_pcie_setup_wins(void __iomem *base,
struct mbus_dram_target_info *dram)
{
u32 size;
int i;
/*
* First, disable and clear BARs and windows.
*/
for (i = 1; i <= 2; i++) {
writel(0, base + PCIE_BAR_CTRL_OFF(i));
writel(0, base + PCIE_BAR_LO_OFF(i));
writel(0, base + PCIE_BAR_HI_OFF(i));
}
for (i = 0; i < 5; i++) {
writel(0, base + PCIE_WIN04_CTRL_OFF(i));
writel(0, base + PCIE_WIN04_BASE_OFF(i));
writel(0, base + PCIE_WIN04_REMAP_OFF(i)); }
writel(0, base + PCIE_WIN5_CTRL_OFF);
writel(0, base + PCIE_WIN5_BASE_OFF);
writel(0, base + PCIE_WIN5_REMAP_OFF);
/*
* Setup windows for DDR banks. Count total DDR size on the fly.
*/
size = 0;
for (i = 0; i < dram->num_cs; i++) {
struct mbus_dram_window *cs = dram->cs + i;
writel(cs->base & 0xffff0000, base + PCIE_WIN04_BASE_OFF(i));
writel(0, base + PCIE_WIN04_REMAP_OFF(i));
writel(((cs->size - 1) & 0xffff0000) |
(cs->mbus_attr << 8) |
(dram->mbus_dram_target_id << 4) | 1,
base + PCIE_WIN04_CTRL_OFF(i));
size += cs->size;
}
/*
* Round up 'size' to the nearest power of two.
*/
if ((size & (size - 1)) != 0)
size = 1 << fls(size);
/*
* Setup BAR[1] to all DRAM banks.
*/
writel(dram->cs[0].base, base + PCIE_BAR_LO_OFF(1));
writel(0, base + PCIE_BAR_HI_OFF(1));
writel(((size - 1) & 0xffff0000) | 1, base + PCIE_BAR_CTRL_OFF(1));
}
void __init orion_pcie_setup(void __iomem *base,
struct mbus_dram_target_info *dram)
{
u16 cmd;
u32 mask;
/*
* Point PCIe unit MBUS decode windows to DRAM space.
*/
orion_pcie_setup_wins(base, dram);
/*
* Master + slave enable.
*/
cmd = readw(base + PCIE_CMD_OFF);
cmd |= PCI_COMMAND_IO;
cmd |= PCI_COMMAND_MEMORY;
cmd |= PCI_COMMAND_MASTER;
writew(cmd, base + PCIE_CMD_OFF);
/*
* Enable interrupt lines A-D.
*/
mask = readl(base + PCIE_MASK_OFF);
mask |= 0x0f000000;
writel(mask, base + PCIE_MASK_OFF);
}
int orion_pcie_rd_conf(void __iomem *base, struct pci_bus *bus,
u32 devfn, int where, int size, u32 *val)
{
writel(PCIE_CONF_BUS(bus->number) |
PCIE_CONF_DEV(PCI_SLOT(devfn)) | PCIE_CONF_FUNC(PCI_FUNC(devfn)) |
PCIE_CONF_REG(where) | PCIE_CONF_ADDR_EN,
base + PCIE_CONF_ADDR_OFF);
*val = readl(base + PCIE_CONF_DATA_OFF);
if (size == 1)
*val = (*val >> (8 * (where & 3))) & 0xff;
else if (size == 2)
*val = (*val >> (8 * (where & 3))) & 0xffff;
return PCIBIOS_SUCCESSFUL;
}
int orion_pcie_rd_conf_tlp(void __iomem *base, struct pci_bus *bus,
u32 devfn, int where, int size, u32 *val)
{
writel(PCIE_CONF_BUS(bus->number) |
PCIE_CONF_DEV(PCI_SLOT(devfn)) |
PCIE_CONF_FUNC(PCI_FUNC(devfn)) |
PCIE_CONF_REG(where) | PCIE_CONF_ADDR_EN,
base + PCIE_CONF_ADDR_OFF);
*val = readl(base + PCIE_CONF_DATA_OFF);
if (bus->number != orion_pcie_get_local_bus_nr(base) ||
PCI_FUNC(devfn) != 0)
*val = readl(base + PCIE_HEADER_LOG_4_OFF);
if (size == 1)
*val = (*val >> (8 * (where & 3))) & 0xff;
else if (size == 2)
*val = (*val >> (8 * (where & 3))) & 0xffff;
return PCIBIOS_SUCCESSFUL;
}
int orion_pcie_rd_conf_wa(void __iomem *wa_base, struct pci_bus *bus,
u32 devfn, int where, int size, u32 *val)
{
*val = readl(wa_base + (PCIE_CONF_BUS(bus->number) |
PCIE_CONF_DEV(PCI_SLOT(devfn)) |
PCIE_CONF_FUNC(PCI_FUNC(devfn)) |
PCIE_CONF_REG(where)));
if (size == 1)
*val = (*val >> (8 * (where & 3))) & 0xff;
else if (size == 2)
*val = (*val >> (8 * (where & 3))) & 0xffff;
return PCIBIOS_SUCCESSFUL;
}
int orion_pcie_wr_conf(void __iomem *base, struct pci_bus *bus,
u32 devfn, int where, int size, u32 val)
{
int ret = PCIBIOS_SUCCESSFUL;
writel(PCIE_CONF_BUS(bus->number) |
PCIE_CONF_DEV(PCI_SLOT(devfn)) |
PCIE_CONF_FUNC(PCI_FUNC(devfn)) |
PCIE_CONF_REG(where) | PCIE_CONF_ADDR_EN,
base + PCIE_CONF_ADDR_OFF);
if (size == 4) {
writel(val, base + PCIE_CONF_DATA_OFF);
} else if (size == 2) {
writew(val, base + PCIE_CONF_DATA_OFF + (where & 3));
} else if (size == 1) {
writeb(val, base + PCIE_CONF_DATA_OFF + (where & 3)); } else {
ret = PCIBIOS_BAD_REGISTER_NUMBER;
}
return ret;
}