linux/arch/arm/mach-orion5x/pci.c
Bjorn Helgaas 9e808eb6a7 PCI: Cleanup control flow
Return errors immediately so the straightline path is the normal,
no-error path.  No functional change.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-03-19 10:17:22 -05:00

584 lines
14 KiB
C

/*
* arch/arm/mach-orion5x/pci.c
*
* PCI and PCIe functions for Marvell Orion System On Chip
*
* Maintainer: Tzachi Perelstein <tzachi@marvell.com>
*
* 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/slab.h>
#include <linux/mbus.h>
#include <video/vga.h>
#include <asm/irq.h>
#include <asm/mach/pci.h>
#include <plat/pcie.h>
#include <plat/addr-map.h>
#include <mach/orion5x.h>
#include "common.h"
/*****************************************************************************
* Orion has one PCIe controller and one PCI controller.
*
* Note1: The local PCIe bus number is '0'. The local PCI bus number
* follows the scanned PCIe bridged busses, if any.
*
* Note2: It is possible for PCI/PCIe agents to access many subsystem's
* space, by configuring BARs and Address Decode Windows, e.g. flashes on
* device bus, Orion registers, etc. However this code only enable the
* access to DDR banks.
****************************************************************************/
/*****************************************************************************
* PCIe controller
****************************************************************************/
#define PCIE_BASE (ORION5X_PCIE_VIRT_BASE)
void __init orion5x_pcie_id(u32 *dev, u32 *rev)
{
*dev = orion_pcie_dev_id(PCIE_BASE);
*rev = orion_pcie_rev(PCIE_BASE);
}
static int pcie_valid_config(int bus, int dev)
{
/*
* Don't go out when trying to access --
* 1. nonexisting device on local bus
* 2. where there's no device connected (no link)
*/
if (bus == 0 && dev == 0)
return 1;
if (!orion_pcie_link_up(PCIE_BASE))
return 0;
if (bus == 0 && dev != 1)
return 0;
return 1;
}
/*
* PCIe config cycles are done by programming the PCIE_CONF_ADDR register
* and then reading the PCIE_CONF_DATA register. Need to make sure these
* transactions are atomic.
*/
static DEFINE_SPINLOCK(orion5x_pcie_lock);
static int pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
int size, u32 *val)
{
unsigned long flags;
int ret;
if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
*val = 0xffffffff;
return PCIBIOS_DEVICE_NOT_FOUND;
}
spin_lock_irqsave(&orion5x_pcie_lock, flags);
ret = orion_pcie_rd_conf(PCIE_BASE, bus, devfn, where, size, val);
spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
return ret;
}
static int pcie_rd_conf_wa(struct pci_bus *bus, u32 devfn,
int where, int size, u32 *val)
{
int ret;
if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
*val = 0xffffffff;
return PCIBIOS_DEVICE_NOT_FOUND;
}
/*
* We only support access to the non-extended configuration
* space when using the WA access method (or we would have to
* sacrifice 256M of CPU virtual address space.)
*/
if (where >= 0x100) {
*val = 0xffffffff;
return PCIBIOS_DEVICE_NOT_FOUND;
}
ret = orion_pcie_rd_conf_wa(ORION5X_PCIE_WA_VIRT_BASE,
bus, devfn, where, size, val);
return ret;
}
static int pcie_wr_conf(struct pci_bus *bus, u32 devfn,
int where, int size, u32 val)
{
unsigned long flags;
int ret;
if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0)
return PCIBIOS_DEVICE_NOT_FOUND;
spin_lock_irqsave(&orion5x_pcie_lock, flags);
ret = orion_pcie_wr_conf(PCIE_BASE, bus, devfn, where, size, val);
spin_unlock_irqrestore(&orion5x_pcie_lock, flags);
return ret;
}
static struct pci_ops pcie_ops = {
.read = pcie_rd_conf,
.write = pcie_wr_conf,
};
static int __init pcie_setup(struct pci_sys_data *sys)
{
struct resource *res;
int dev;
/*
* Generic PCIe unit setup.
*/
orion_pcie_setup(PCIE_BASE);
/*
* Check whether to apply Orion-1/Orion-NAS PCIe config
* read transaction workaround.
*/
dev = orion_pcie_dev_id(PCIE_BASE);
if (dev == MV88F5181_DEV_ID || dev == MV88F5182_DEV_ID) {
printk(KERN_NOTICE "Applying Orion-1/Orion-NAS PCIe config "
"read transaction workaround\n");
mvebu_mbus_add_window_by_id(ORION_MBUS_PCIE_WA_TARGET,
ORION_MBUS_PCIE_WA_ATTR,
ORION5X_PCIE_WA_PHYS_BASE,
ORION5X_PCIE_WA_SIZE);
pcie_ops.read = pcie_rd_conf_wa;
}
pci_ioremap_io(sys->busnr * SZ_64K, ORION5X_PCIE_IO_PHYS_BASE);
/*
* Request resources.
*/
res = kzalloc(sizeof(struct resource), GFP_KERNEL);
if (!res)
panic("pcie_setup unable to alloc resources");
/*
* IORESOURCE_MEM
*/
res->name = "PCIe Memory Space";
res->flags = IORESOURCE_MEM;
res->start = ORION5X_PCIE_MEM_PHYS_BASE;
res->end = res->start + ORION5X_PCIE_MEM_SIZE - 1;
if (request_resource(&iomem_resource, res))
panic("Request PCIe Memory resource failed\n");
pci_add_resource_offset(&sys->resources, res, sys->mem_offset);
return 1;
}
/*****************************************************************************
* PCI controller
****************************************************************************/
#define ORION5X_PCI_REG(x) (ORION5X_PCI_VIRT_BASE + (x))
#define PCI_MODE ORION5X_PCI_REG(0xd00)
#define PCI_CMD ORION5X_PCI_REG(0xc00)
#define PCI_P2P_CONF ORION5X_PCI_REG(0x1d14)
#define PCI_CONF_ADDR ORION5X_PCI_REG(0xc78)
#define PCI_CONF_DATA ORION5X_PCI_REG(0xc7c)
/*
* PCI_MODE bits
*/
#define PCI_MODE_64BIT (1 << 2)
#define PCI_MODE_PCIX ((1 << 4) | (1 << 5))
/*
* PCI_CMD bits
*/
#define PCI_CMD_HOST_REORDER (1 << 29)
/*
* PCI_P2P_CONF bits
*/
#define PCI_P2P_BUS_OFFS 16
#define PCI_P2P_BUS_MASK (0xff << PCI_P2P_BUS_OFFS)
#define PCI_P2P_DEV_OFFS 24
#define PCI_P2P_DEV_MASK (0x1f << PCI_P2P_DEV_OFFS)
/*
* PCI_CONF_ADDR bits
*/
#define PCI_CONF_REG(reg) ((reg) & 0xfc)
#define PCI_CONF_FUNC(func) (((func) & 0x3) << 8)
#define PCI_CONF_DEV(dev) (((dev) & 0x1f) << 11)
#define PCI_CONF_BUS(bus) (((bus) & 0xff) << 16)
#define PCI_CONF_ADDR_EN (1 << 31)
/*
* Internal configuration space
*/
#define PCI_CONF_FUNC_STAT_CMD 0
#define PCI_CONF_REG_STAT_CMD 4
#define PCIX_STAT 0x64
#define PCIX_STAT_BUS_OFFS 8
#define PCIX_STAT_BUS_MASK (0xff << PCIX_STAT_BUS_OFFS)
/*
* PCI Address Decode Windows registers
*/
#define PCI_BAR_SIZE_DDR_CS(n) (((n) == 0) ? ORION5X_PCI_REG(0xc08) : \
((n) == 1) ? ORION5X_PCI_REG(0xd08) : \
((n) == 2) ? ORION5X_PCI_REG(0xc0c) : \
((n) == 3) ? ORION5X_PCI_REG(0xd0c) : NULL)
#define PCI_BAR_REMAP_DDR_CS(n) (((n) == 0) ? ORION5X_PCI_REG(0xc48) : \
((n) == 1) ? ORION5X_PCI_REG(0xd48) : \
((n) == 2) ? ORION5X_PCI_REG(0xc4c) : \
((n) == 3) ? ORION5X_PCI_REG(0xd4c) : NULL)
#define PCI_BAR_ENABLE ORION5X_PCI_REG(0xc3c)
#define PCI_ADDR_DECODE_CTRL ORION5X_PCI_REG(0xd3c)
/*
* PCI configuration helpers for BAR settings
*/
#define PCI_CONF_FUNC_BAR_CS(n) ((n) >> 1)
#define PCI_CONF_REG_BAR_LO_CS(n) (((n) & 1) ? 0x18 : 0x10)
#define PCI_CONF_REG_BAR_HI_CS(n) (((n) & 1) ? 0x1c : 0x14)
/*
* PCI config cycles are done by programming the PCI_CONF_ADDR register
* and then reading the PCI_CONF_DATA register. Need to make sure these
* transactions are atomic.
*/
static DEFINE_SPINLOCK(orion5x_pci_lock);
static int orion5x_pci_cardbus_mode;
static int orion5x_pci_local_bus_nr(void)
{
u32 conf = readl(PCI_P2P_CONF);
return((conf & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS);
}
static int orion5x_pci_hw_rd_conf(int bus, int dev, u32 func,
u32 where, u32 size, u32 *val)
{
unsigned long flags;
spin_lock_irqsave(&orion5x_pci_lock, flags);
writel(PCI_CONF_BUS(bus) |
PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
*val = readl(PCI_CONF_DATA);
if (size == 1)
*val = (*val >> (8*(where & 0x3))) & 0xff;
else if (size == 2)
*val = (*val >> (8*(where & 0x3))) & 0xffff;
spin_unlock_irqrestore(&orion5x_pci_lock, flags);
return PCIBIOS_SUCCESSFUL;
}
static int orion5x_pci_hw_wr_conf(int bus, int dev, u32 func,
u32 where, u32 size, u32 val)
{
unsigned long flags;
int ret = PCIBIOS_SUCCESSFUL;
spin_lock_irqsave(&orion5x_pci_lock, flags);
writel(PCI_CONF_BUS(bus) |
PCI_CONF_DEV(dev) | PCI_CONF_REG(where) |
PCI_CONF_FUNC(func) | PCI_CONF_ADDR_EN, PCI_CONF_ADDR);
if (size == 4) {
__raw_writel(val, PCI_CONF_DATA);
} else if (size == 2) {
__raw_writew(val, PCI_CONF_DATA + (where & 0x3));
} else if (size == 1) {
__raw_writeb(val, PCI_CONF_DATA + (where & 0x3));
} else {
ret = PCIBIOS_BAD_REGISTER_NUMBER;
}
spin_unlock_irqrestore(&orion5x_pci_lock, flags);
return ret;
}
static int orion5x_pci_valid_config(int bus, u32 devfn)
{
if (bus == orion5x_pci_local_bus_nr()) {
/*
* Don't go out for local device
*/
if (PCI_SLOT(devfn) == 0 && PCI_FUNC(devfn) != 0)
return 0;
/*
* When the PCI signals are directly connected to a
* Cardbus slot, ignore all but device IDs 0 and 1.
*/
if (orion5x_pci_cardbus_mode && PCI_SLOT(devfn) > 1)
return 0;
}
return 1;
}
static int orion5x_pci_rd_conf(struct pci_bus *bus, u32 devfn,
int where, int size, u32 *val)
{
if (!orion5x_pci_valid_config(bus->number, devfn)) {
*val = 0xffffffff;
return PCIBIOS_DEVICE_NOT_FOUND;
}
return orion5x_pci_hw_rd_conf(bus->number, PCI_SLOT(devfn),
PCI_FUNC(devfn), where, size, val);
}
static int orion5x_pci_wr_conf(struct pci_bus *bus, u32 devfn,
int where, int size, u32 val)
{
if (!orion5x_pci_valid_config(bus->number, devfn))
return PCIBIOS_DEVICE_NOT_FOUND;
return orion5x_pci_hw_wr_conf(bus->number, PCI_SLOT(devfn),
PCI_FUNC(devfn), where, size, val);
}
static struct pci_ops pci_ops = {
.read = orion5x_pci_rd_conf,
.write = orion5x_pci_wr_conf,
};
static void __init orion5x_pci_set_bus_nr(int nr)
{
u32 p2p = readl(PCI_P2P_CONF);
if (readl(PCI_MODE) & PCI_MODE_PCIX) {
/*
* PCI-X mode
*/
u32 pcix_status, bus, dev;
bus = (p2p & PCI_P2P_BUS_MASK) >> PCI_P2P_BUS_OFFS;
dev = (p2p & PCI_P2P_DEV_MASK) >> PCI_P2P_DEV_OFFS;
orion5x_pci_hw_rd_conf(bus, dev, 0, PCIX_STAT, 4, &pcix_status);
pcix_status &= ~PCIX_STAT_BUS_MASK;
pcix_status |= (nr << PCIX_STAT_BUS_OFFS);
orion5x_pci_hw_wr_conf(bus, dev, 0, PCIX_STAT, 4, pcix_status);
} else {
/*
* PCI Conventional mode
*/
p2p &= ~PCI_P2P_BUS_MASK;
p2p |= (nr << PCI_P2P_BUS_OFFS);
writel(p2p, PCI_P2P_CONF);
}
}
static void __init orion5x_pci_master_slave_enable(void)
{
int bus_nr, func, reg;
u32 val;
bus_nr = orion5x_pci_local_bus_nr();
func = PCI_CONF_FUNC_STAT_CMD;
reg = PCI_CONF_REG_STAT_CMD;
orion5x_pci_hw_rd_conf(bus_nr, 0, func, reg, 4, &val);
val |= (PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
orion5x_pci_hw_wr_conf(bus_nr, 0, func, reg, 4, val | 0x7);
}
static void __init orion5x_setup_pci_wins(void)
{
const struct mbus_dram_target_info *dram = mv_mbus_dram_info();
u32 win_enable;
int bus;
int i;
/*
* First, disable windows.
*/
win_enable = 0xffffffff;
writel(win_enable, PCI_BAR_ENABLE);
/*
* Setup windows for DDR banks.
*/
bus = orion5x_pci_local_bus_nr();
for (i = 0; i < dram->num_cs; i++) {
const struct mbus_dram_window *cs = dram->cs + i;
u32 func = PCI_CONF_FUNC_BAR_CS(cs->cs_index);
u32 reg;
u32 val;
/*
* Write DRAM bank base address register.
*/
reg = PCI_CONF_REG_BAR_LO_CS(cs->cs_index);
orion5x_pci_hw_rd_conf(bus, 0, func, reg, 4, &val);
val = (cs->base & 0xfffff000) | (val & 0xfff);
orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, val);
/*
* Write DRAM bank size register.
*/
reg = PCI_CONF_REG_BAR_HI_CS(cs->cs_index);
orion5x_pci_hw_wr_conf(bus, 0, func, reg, 4, 0);
writel((cs->size - 1) & 0xfffff000,
PCI_BAR_SIZE_DDR_CS(cs->cs_index));
writel(cs->base & 0xfffff000,
PCI_BAR_REMAP_DDR_CS(cs->cs_index));
/*
* Enable decode window for this chip select.
*/
win_enable &= ~(1 << cs->cs_index);
}
/*
* Re-enable decode windows.
*/
writel(win_enable, PCI_BAR_ENABLE);
/*
* Disable automatic update of address remapping when writing to BARs.
*/
orion5x_setbits(PCI_ADDR_DECODE_CTRL, 1);
}
static int __init pci_setup(struct pci_sys_data *sys)
{
struct resource *res;
/*
* Point PCI unit MBUS decode windows to DRAM space.
*/
orion5x_setup_pci_wins();
/*
* Master + Slave enable
*/
orion5x_pci_master_slave_enable();
/*
* Force ordering
*/
orion5x_setbits(PCI_CMD, PCI_CMD_HOST_REORDER);
pci_ioremap_io(sys->busnr * SZ_64K, ORION5X_PCI_IO_PHYS_BASE);
/*
* Request resources
*/
res = kzalloc(sizeof(struct resource), GFP_KERNEL);
if (!res)
panic("pci_setup unable to alloc resources");
/*
* IORESOURCE_MEM
*/
res->name = "PCI Memory Space";
res->flags = IORESOURCE_MEM;
res->start = ORION5X_PCI_MEM_PHYS_BASE;
res->end = res->start + ORION5X_PCI_MEM_SIZE - 1;
if (request_resource(&iomem_resource, res))
panic("Request PCI Memory resource failed\n");
pci_add_resource_offset(&sys->resources, res, sys->mem_offset);
return 1;
}
/*****************************************************************************
* General PCIe + PCI
****************************************************************************/
static void rc_pci_fixup(struct pci_dev *dev)
{
/*
* Prevent enumeration of root complex.
*/
if (dev->bus->parent == NULL && dev->devfn == 0) {
int i;
for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
dev->resource[i].start = 0;
dev->resource[i].end = 0;
dev->resource[i].flags = 0;
}
}
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
static int orion5x_pci_disabled __initdata;
void __init orion5x_pci_disable(void)
{
orion5x_pci_disabled = 1;
}
void __init orion5x_pci_set_cardbus_mode(void)
{
orion5x_pci_cardbus_mode = 1;
}
int __init orion5x_pci_sys_setup(int nr, struct pci_sys_data *sys)
{
vga_base = ORION5X_PCIE_MEM_PHYS_BASE;
if (nr == 0) {
orion_pcie_set_local_bus_nr(PCIE_BASE, sys->busnr);
return pcie_setup(sys);
}
if (nr == 1 && !orion5x_pci_disabled) {
orion5x_pci_set_bus_nr(sys->busnr);
return pci_setup(sys);
}
return 0;
}
struct pci_bus __init *orion5x_pci_sys_scan_bus(int nr, struct pci_sys_data *sys)
{
if (nr == 0)
return pci_scan_root_bus(NULL, sys->busnr, &pcie_ops, sys,
&sys->resources);
if (nr == 1 && !orion5x_pci_disabled)
return pci_scan_root_bus(NULL, sys->busnr, &pci_ops, sys,
&sys->resources);
BUG();
return NULL;
}
int __init orion5x_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
int bus = dev->bus->number;
/*
* PCIe endpoint?
*/
if (orion5x_pci_disabled || bus < orion5x_pci_local_bus_nr())
return IRQ_ORION5X_PCIE0_INT;
return -1;
}