/*
* arch/arm/mach-ixp4xx/common-pci.c
*
* IXP4XX PCI routines for all platforms
*
* Maintainer: Deepak Saxena <dsaxena@plexity.net>
*
* Copyright (C) 2002 Intel Corporation.
* Copyright (C) 2003 Greg Ungerer <gerg@snapgear.com>
* Copyright (C) 2003-2004 MontaVista Software, Inc.
*
* 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.
*
*/
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/io.h>
#include <asm/dma-mapping.h>
#include <asm/cputype.h>
#include <asm/irq.h>
#include <asm/sizes.h>
#include <asm/system.h>
#include <asm/mach/pci.h>
#include <mach/hardware.h>
/*
* IXP4xx PCI read function is dependent on whether we are
* running A0 or B0 (AppleGate) silicon.
*/
int (*ixp4xx_pci_read)(u32 addr, u32 cmd, u32* data);
/*
* Base address for PCI regsiter region
*/
unsigned long ixp4xx_pci_reg_base = 0;
/*
* PCI cfg an I/O routines are done by programming a
* command/byte enable register, and then read/writing
* the data from a data regsiter. We need to ensure
* these transactions are atomic or we will end up
* with corrupt data on the bus or in a driver.
*/
static DEFINE_SPINLOCK(ixp4xx_pci_lock);
/*
* Read from PCI config space
*/
static void crp_read(u32 ad_cbe, u32 *data)
{
unsigned long flags;
spin_lock_irqsave(&ixp4xx_pci_lock, flags);
*PCI_CRP_AD_CBE = ad_cbe;
*data = *PCI_CRP_RDATA;
spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
}
/*
* Write to PCI config space
*/
static void crp_write(u32 ad_cbe, u32 data)
{
unsigned long flags;
spin_lock_irqsave(&ixp4xx_pci_lock, flags);
*PCI_CRP_AD_CBE = CRP_AD_CBE_WRITE | ad_cbe;
*PCI_CRP_WDATA = data;
spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
}
static inline int check_master_abort(void)
{
/* check Master Abort bit after access */
unsigned long isr = *PCI_ISR;
if (isr & PCI_ISR_PFE) {
/* make sure the Master Abort bit is reset */
*PCI_ISR = PCI_ISR_PFE;
pr_debug("%s failed\n", __func__);
return 1;
}
return 0;
}
int ixp4xx_pci_read_errata(u32 addr, u32 cmd, u32* data)
{
unsigned long flags;
int retval = 0;
int i;
spin_lock_irqsave(&ixp4xx_pci_lock, flags);
*PCI_NP_AD = addr;
/*
* PCI workaround - only works if NP PCI space reads have
* no side effects!!! Read 8 times. last one will be good.
*/
for (i = 0; i < 8; i++) {
*PCI_NP_CBE = cmd;
*data = *PCI_NP_RDATA;
*data = *PCI_NP_RDATA;
}
if(check_master_abort())
retval = 1;
spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
return retval;
}
int ixp4xx_pci_read_no_errata(u32 addr, u32 cmd, u32* data)
{
unsigned long flags;
int retval = 0;
spin_lock_irqsave(&ixp4xx_pci_lock, flags);
*PCI_NP_AD = addr;
/* set up and execute the read */
*PCI_NP_CBE = cmd;
/* the result of the read is now in NP_RDATA */
*data = *PCI_NP_RDATA;
if(check_master_abort())
retval = 1;
spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
return retval;
}
int ixp4xx_pci_write(u32 addr, u32 cmd, u32 data)
{
unsigned long flags;
int retval = 0;
spin_lock_irqsave(&ixp4xx_pci_lock, flags);
*PCI_NP_AD = addr;
/* set up the write */
*PCI_NP_CBE = cmd;
/* execute the write by writing to NP_WDATA */
*PCI_NP_WDATA = data;
if(check_master_abort())
retval = 1;
spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
return retval;
}
static u32 ixp4xx_config_addr(u8 bus_num, u16 devfn, int where)
{
u32 addr;
if (!bus_num) {
/* type 0 */
addr = BIT(32-PCI_SLOT(devfn)) | ((PCI_FUNC(devfn)) << 8) |
(where & ~3);
} else {
/* type 1 */
addr = (bus_num << 16) | ((PCI_SLOT(devfn)) << 11) |
((PCI_FUNC(devfn)) << 8) | (where & ~3) | 1;
}
return addr;
}
/*
* Mask table, bits to mask for quantity of size 1, 2 or 4 bytes.
* 0 and 3 are not valid indexes...
*/
static u32 bytemask[] = {
/*0*/ 0,
/*1*/ 0xff,
/*2*/ 0xffff,
/*3*/ 0,
/*4*/ 0xffffffff,
};
static u32 local_byte_lane_enable_bits(u32 n, int size)
{
if (size == 1)
return (0xf & ~BIT(n)) << CRP_AD_CBE_BESL;
if (size == 2)
return (0xf & ~(BIT(n) | BIT(n+1))) << CRP_AD_CBE_BESL;
if (size == 4)
return 0;
return 0xffffffff;
}
static int local_read_config(int where, int size, u32 *value)
{
u32 n, data;
pr_debug("local_read_config from %d size %d\n", where, size);
n = where % 4;
crp_read(where & ~3, &data);
*value = (data >> (8*n)) & bytemask[size];
pr_debug("local_read_config read %#x\n", *value);
return PCIBIOS_SUCCESSFUL;
}
static int local_write_config(int where, int size, u32 value)
{
u32 n, byte_enables, data;
pr_debug("local_write_config %#x to %d size %d\n", value, where, size);
n = where % 4;
byte_enables = local_byte_lane_enable_bits(n, size);
if (byte_enables == 0xffffffff)
return PCIBIOS_BAD_REGISTER_NUMBER;
data = value << (8*n);
crp_write((where & ~3) | byte_enables, data);
return PCIBIOS_SUCCESSFUL;
}
static u32 byte_lane_enable_bits(u32 n, int size)
{
if (size == 1)
return (0xf & ~BIT(n)) << 4;
if (size == 2)
return (0xf & ~(BIT(n) | BIT(n+1))) << 4;
if (size == 4)
return 0;
return 0xffffffff;
}
static int ixp4xx_pci_read_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
{
u32 n, byte_enables, addr, data;
u8 bus_num = bus->number;
pr_debug("read_config from %d size %d dev %d:%d:%d\n", where, size,
bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn));
*value = 0xffffffff;
n = where % 4;
byte_enables = byte_lane_enable_bits(n, size);
if (byte_enables == 0xffffffff)
return PCIBIOS_BAD_REGISTER_NUMBER;
addr = ixp4xx_config_addr(bus_num, devfn, where);
if (ixp4xx_pci_read(addr, byte_enables | NP_CMD_CONFIGREAD, &data))
return PCIBIOS_DEVICE_NOT_FOUND;
*value = (data >> (8*n)) & bytemask[size];
pr_debug("read_config_byte read %#x\n", *value);
return PCIBIOS_SUCCESSFUL;
}
static int ixp4xx_pci_write_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 value)
{
u32 n, byte_enables, addr, data;
u8 bus_num = bus->number;
pr_debug("write_config_byte %#x to %d size %d dev %d:%d:%d\n", value, where,
size, bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn));
n = where % 4;
byte_enables = byte_lane_enable_bits(n, size);
if (byte_enables == 0xffffffff)
return PCIBIOS_BAD_REGISTER_NUMBER;
addr = ixp4xx_config_addr(bus_num, devfn, where);
data = value << (8*n);
if (ixp4xx_pci_write(addr, byte_enables | NP_CMD_CONFIGWRITE, data))
return PCIBIOS_DEVICE_NOT_FOUND;
return PCIBIOS_SUCCESSFUL;
}
struct pci_ops ixp4xx_ops = {
.read = ixp4xx_pci_read_config,
.write = ixp4xx_pci_write_config,
};
/*
* PCI abort handler
*/
static int abort_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
{
u32 isr, status;
isr = *PCI_ISR;
local_read_config(PCI_STATUS, 2, &status);
pr_debug("PCI: abort_handler addr = %#lx, isr = %#x, "
"status = %#x\n", addr, isr, status);
/* make sure the Master Abort bit is reset */
*PCI_ISR = PCI_ISR_PFE;
status |= PCI_STATUS_REC_MASTER_ABORT;
local_write_config(PCI_STATUS, 2, status);
/*
* If it was an imprecise abort, then we need to correct the
* return address to be _after_ the instruction.
*/
if (fsr & (1 << 10))
regs->ARM_pc += 4;
return 0;
}
/*
* Setup DMA mask to 64MB on PCI devices. Ignore all other devices.
*/
static int ixp4xx_pci_platform_notify(struct device *dev)
{
if(dev->bus == &pci_bus_type) {
*dev->dma_mask = SZ_64M - 1;
dev->coherent_dma_mask = SZ_64M - 1;
dmabounce_register_dev(dev, 2048, 4096);
}
return 0;
}
static int ixp4xx_pci_platform_notify_remove(struct device *dev)
{
if(dev->bus == &pci_bus_type) {
dmabounce_unregister_dev(dev);
}
return 0;
}
int dma_needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size)
{
return (dev->bus == &pci_bus_type ) && ((dma_addr + size) >= SZ_64M);
}
/*
* Only first 64MB of memory can be accessed via PCI.
* We use GFP_DMA to allocate safe buffers to do map/unmap.
* This is really ugly and we need a better way of specifying
* DMA-capable regions of memory.
*/
void __init ixp4xx_adjust_zones(int node, unsigned long *zone_size,
unsigned long *zhole_size)
{
unsigned int sz = SZ_64M >> PAGE_SHIFT;
/*
* Only adjust if > 64M on current system
*/
if (node || (zone_size[0] <= sz))
return;
zone_size[1] = zone_size[0] - sz;
zone_size[0] = sz;
zhole_size[1] = zhole_size[0];
zhole_size[0] = 0;
}
void __init ixp4xx_pci_preinit(void)
{
unsigned long cpuid = read_cpuid_id();
/*
* Determine which PCI read method to use.
* Rev 0 IXP425 requires workaround.
*/
if (!(cpuid & 0xf) && cpu_is_ixp42x()) {
printk("PCI: IXP42x A0 silicon detected - "
"PCI Non-Prefetch Workaround Enabled\n");
ixp4xx_pci_read = ixp4xx_pci_read_errata;
} else
ixp4xx_pci_read = ixp4xx_pci_read_no_errata;
/* hook in our fault handler for PCI errors */
hook_fault_code(16+6, abort_handler, SIGBUS, "imprecise external abort");
pr_debug("setup PCI-AHB(inbound) and AHB-PCI(outbound) address mappings\n");
/*
* We use identity AHB->PCI address translation
* in the 0x48000000 to 0x4bffffff address space
*/
*PCI_PCIMEMBASE = 0x48494A4B;
/*
* We also use identity PCI->AHB address translation
* in 4 16MB BARs that begin at the physical memory start
*/
*PCI_AHBMEMBASE = (PHYS_OFFSET & 0xFF000000) +
((PHYS_OFFSET & 0xFF000000) >> 8) +
((PHYS_OFFSET & 0xFF000000) >> 16) +
((PHYS_OFFSET & 0xFF000000) >> 24) +
0x00010203;
if (*PCI_CSR & PCI_CSR_HOST) {
printk("PCI: IXP4xx is host\n");
pr_debug("setup BARs in controller\n");
/*
* We configure the PCI inbound memory windows to be
* 1:1 mapped to SDRAM
*/
local_write_config(PCI_BASE_ADDRESS_0, 4, PHYS_OFFSET);
local_write_config(PCI_BASE_ADDRESS_1, 4, PHYS_OFFSET + SZ_16M);
local_write_config(PCI_BASE_ADDRESS_2, 4, PHYS_OFFSET + SZ_32M);
local_write_config(PCI_BASE_ADDRESS_3, 4, PHYS_OFFSET + SZ_48M);
/*
* Enable CSR window at 64 MiB to allow PCI masters
* to continue prefetching past 64 MiB boundary.
*/
local_write_config(PCI_BASE_ADDRESS_4, 4, PHYS_OFFSET + SZ_64M);
/*
* Enable the IO window to be way up high, at 0xfffffc00
*/
local_write_config(PCI_BASE_ADDRESS_5, 4, 0xfffffc01);
} else {
printk("PCI: IXP4xx is target - No bus scan performed\n");
}
printk("PCI: IXP4xx Using %s access for memory space\n",
#ifndef CONFIG_IXP4XX_INDIRECT_PCI
"direct"
#else
"indirect"
#endif
);
pr_debug("clear error bits in ISR\n");
*PCI_ISR = PCI_ISR_PSE | PCI_ISR_PFE | PCI_ISR_PPE | PCI_ISR_AHBE;
/*
* Set Initialize Complete in PCI Control Register: allow IXP4XX to
* respond to PCI configuration cycles. Specify that the AHB bus is
* operating in big endian mode. Set up byte lane swapping between
* little-endian PCI and the big-endian AHB bus
*/
#ifdef __ARMEB__
*PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE | PCI_CSR_PDS | PCI_CSR_ADS;
#else
*PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE;
#endif
pr_debug("DONE\n");
}
int ixp4xx_setup(int nr, struct pci_sys_data *sys)
{
struct resource *res;
if (nr >= 1)
return 0;
res = kzalloc(sizeof(*res) * 2, GFP_KERNEL);
if (res == NULL) {
/*
* If we're out of memory this early, something is wrong,
* so we might as well catch it here.
*/
panic("PCI: unable to allocate resources?\n");
}
local_write_config(PCI_COMMAND, 2, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);
res[0].name = "PCI I/O Space";
res[0].start = 0x00000000;
res[0].end = 0x0000ffff;
res[0].flags = IORESOURCE_IO;
res[1].name = "PCI Memory Space";
res[1].start = PCIBIOS_MIN_MEM;
res[1].end = PCIBIOS_MAX_MEM;
res[1].flags = IORESOURCE_MEM;
request_resource(&ioport_resource, &res[0]);
request_resource(&iomem_resource, &res[1]);
sys->resource[0] = &res[0];
sys->resource[1] = &res[1];
sys->resource[2] = NULL;
platform_notify = ixp4xx_pci_platform_notify;
platform_notify_remove = ixp4xx_pci_platform_notify_remove;
return 1;
}
struct pci_bus * __devinit ixp4xx_scan_bus(int nr, struct pci_sys_data *sys)
{
return pci_scan_bus(sys->busnr, &ixp4xx_ops, sys);
}
EXPORT_SYMBOL(ixp4xx_pci_read);
EXPORT_SYMBOL(ixp4xx_pci_write);
