linux-stable/include/asm-powerpc/eeh.h
Paul Mackerras f007cacffc [POWERPC] Fix MMIO ops to provide expected barrier behaviour
This changes the writeX family of functions to have a sync instruction
before the MMIO store rather than after, because the generally expected
behaviour is that the device receiving the MMIO store can be guaranteed
to see the effects of any preceding writes to normal memory.

To preserve ordering between writeX and readX, and to preserve ordering
between preceding stores and the readX, the readX family of functions
have had an sync added before the load.

Although writeX followed by spin_unlock is not officially guaranteed
to keep the writeX inside the spin-locked region unless an mmiowb()
is used, there are currently drivers that depend on the previous
behaviour on powerpc, which was that the mmiowb wasn't actually required.
Therefore we have a per-cpu flag that is set by writeX, cleared by
__raw_spin_lock and mmiowb, and tested by __raw_spin_unlock.  If it is
set, __raw_spin_unlock does a sync and clears it.

This changes both 32-bit and 64-bit readX/writeX.  32-bit already has a
sync in __raw_spin_unlock (since lwsync doesn't exist on 32-bit), and thus
doesn't need the per-cpu flag.

Tested on G5 (PPC970) and POWER5.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-09-13 22:08:26 +10:00

360 lines
9.2 KiB
C

/*
* eeh.h
* Copyright (C) 2001 Dave Engebretsen & Todd Inglett IBM Corporation.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _PPC64_EEH_H
#define _PPC64_EEH_H
#ifdef __KERNEL__
#include <linux/init.h>
#include <linux/list.h>
#include <linux/string.h>
struct pci_dev;
struct pci_bus;
struct device_node;
#ifdef CONFIG_EEH
extern int eeh_subsystem_enabled;
/* Values for eeh_mode bits in device_node */
#define EEH_MODE_SUPPORTED (1<<0)
#define EEH_MODE_NOCHECK (1<<1)
#define EEH_MODE_ISOLATED (1<<2)
#define EEH_MODE_RECOVERING (1<<3)
#define EEH_MODE_IRQ_DISABLED (1<<4)
/* Max number of EEH freezes allowed before we consider the device
* to be permanently disabled. */
#define EEH_MAX_ALLOWED_FREEZES 5
void __init eeh_init(void);
unsigned long eeh_check_failure(const volatile void __iomem *token,
unsigned long val);
int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev);
void __init pci_addr_cache_build(void);
/**
* eeh_add_device_early
* eeh_add_device_late
*
* Perform eeh initialization for devices added after boot.
* Call eeh_add_device_early before doing any i/o to the
* device (including config space i/o). Call eeh_add_device_late
* to finish the eeh setup for this device.
*/
void eeh_add_device_tree_early(struct device_node *);
void eeh_add_device_tree_late(struct pci_bus *);
/**
* eeh_remove_device_recursive - undo EEH for device & children.
* @dev: pci device to be removed
*
* As above, this removes the device; it also removes child
* pci devices as well.
*/
void eeh_remove_bus_device(struct pci_dev *);
/**
* EEH_POSSIBLE_ERROR() -- test for possible MMIO failure.
*
* If this macro yields TRUE, the caller relays to eeh_check_failure()
* which does further tests out of line.
*/
#define EEH_POSSIBLE_ERROR(val, type) ((val) == (type)~0 && eeh_subsystem_enabled)
/*
* Reads from a device which has been isolated by EEH will return
* all 1s. This macro gives an all-1s value of the given size (in
* bytes: 1, 2, or 4) for comparing with the result of a read.
*/
#define EEH_IO_ERROR_VALUE(size) (~0U >> ((4 - (size)) * 8))
#else /* !CONFIG_EEH */
static inline void eeh_init(void) { }
static inline unsigned long eeh_check_failure(const volatile void __iomem *token, unsigned long val)
{
return val;
}
static inline int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev)
{
return 0;
}
static inline void pci_addr_cache_build(void) { }
static inline void eeh_add_device_tree_early(struct device_node *dn) { }
static inline void eeh_add_device_tree_late(struct pci_bus *bus) { }
static inline void eeh_remove_bus_device(struct pci_dev *dev) { }
#define EEH_POSSIBLE_ERROR(val, type) (0)
#define EEH_IO_ERROR_VALUE(size) (-1UL)
#endif /* CONFIG_EEH */
/*
* MMIO read/write operations with EEH support.
*/
static inline u8 eeh_readb(const volatile void __iomem *addr)
{
u8 val = in_8(addr);
if (EEH_POSSIBLE_ERROR(val, u8))
return eeh_check_failure(addr, val);
return val;
}
static inline void eeh_writeb(u8 val, volatile void __iomem *addr)
{
out_8(addr, val);
}
static inline u16 eeh_readw(const volatile void __iomem *addr)
{
u16 val = in_le16(addr);
if (EEH_POSSIBLE_ERROR(val, u16))
return eeh_check_failure(addr, val);
return val;
}
static inline void eeh_writew(u16 val, volatile void __iomem *addr)
{
out_le16(addr, val);
}
static inline u16 eeh_raw_readw(const volatile void __iomem *addr)
{
u16 val = in_be16(addr);
if (EEH_POSSIBLE_ERROR(val, u16))
return eeh_check_failure(addr, val);
return val;
}
static inline void eeh_raw_writew(u16 val, volatile void __iomem *addr) {
volatile u16 __iomem *vaddr = (volatile u16 __iomem *) addr;
out_be16(vaddr, val);
}
static inline u32 eeh_readl(const volatile void __iomem *addr)
{
u32 val = in_le32(addr);
if (EEH_POSSIBLE_ERROR(val, u32))
return eeh_check_failure(addr, val);
return val;
}
static inline void eeh_writel(u32 val, volatile void __iomem *addr)
{
out_le32(addr, val);
}
static inline u32 eeh_raw_readl(const volatile void __iomem *addr)
{
u32 val = in_be32(addr);
if (EEH_POSSIBLE_ERROR(val, u32))
return eeh_check_failure(addr, val);
return val;
}
static inline void eeh_raw_writel(u32 val, volatile void __iomem *addr)
{
out_be32(addr, val);
}
static inline u64 eeh_readq(const volatile void __iomem *addr)
{
u64 val = in_le64(addr);
if (EEH_POSSIBLE_ERROR(val, u64))
return eeh_check_failure(addr, val);
return val;
}
static inline void eeh_writeq(u64 val, volatile void __iomem *addr)
{
out_le64(addr, val);
}
static inline u64 eeh_raw_readq(const volatile void __iomem *addr)
{
u64 val = in_be64(addr);
if (EEH_POSSIBLE_ERROR(val, u64))
return eeh_check_failure(addr, val);
return val;
}
static inline void eeh_raw_writeq(u64 val, volatile void __iomem *addr)
{
out_be64(addr, val);
}
#define EEH_CHECK_ALIGN(v,a) \
((((unsigned long)(v)) & ((a) - 1)) == 0)
static inline void eeh_memset_io(volatile void __iomem *addr, int c,
unsigned long n)
{
void *p = (void __force *)addr;
u32 lc = c;
lc |= lc << 8;
lc |= lc << 16;
__asm__ __volatile__ ("sync" : : : "memory");
while(n && !EEH_CHECK_ALIGN(p, 4)) {
*((volatile u8 *)p) = c;
p++;
n--;
}
while(n >= 4) {
*((volatile u32 *)p) = lc;
p += 4;
n -= 4;
}
while(n) {
*((volatile u8 *)p) = c;
p++;
n--;
}
__asm__ __volatile__ ("sync" : : : "memory");
}
static inline void eeh_memcpy_fromio(void *dest, const volatile void __iomem *src,
unsigned long n)
{
void *vsrc = (void __force *) src;
void *destsave = dest;
unsigned long nsave = n;
__asm__ __volatile__ ("sync" : : : "memory");
while(n && (!EEH_CHECK_ALIGN(vsrc, 4) || !EEH_CHECK_ALIGN(dest, 4))) {
*((u8 *)dest) = *((volatile u8 *)vsrc);
__asm__ __volatile__ ("eieio" : : : "memory");
vsrc++;
dest++;
n--;
}
while(n > 4) {
*((u32 *)dest) = *((volatile u32 *)vsrc);
__asm__ __volatile__ ("eieio" : : : "memory");
vsrc += 4;
dest += 4;
n -= 4;
}
while(n) {
*((u8 *)dest) = *((volatile u8 *)vsrc);
__asm__ __volatile__ ("eieio" : : : "memory");
vsrc++;
dest++;
n--;
}
__asm__ __volatile__ ("sync" : : : "memory");
/* Look for ffff's here at dest[n]. Assume that at least 4 bytes
* were copied. Check all four bytes.
*/
if ((nsave >= 4) &&
(EEH_POSSIBLE_ERROR((*((u32 *) destsave+nsave-4)), u32))) {
eeh_check_failure(src, (*((u32 *) destsave+nsave-4)));
}
}
static inline void eeh_memcpy_toio(volatile void __iomem *dest, const void *src,
unsigned long n)
{
void *vdest = (void __force *) dest;
__asm__ __volatile__ ("sync" : : : "memory");
while(n && (!EEH_CHECK_ALIGN(vdest, 4) || !EEH_CHECK_ALIGN(src, 4))) {
*((volatile u8 *)vdest) = *((u8 *)src);
src++;
vdest++;
n--;
}
while(n > 4) {
*((volatile u32 *)vdest) = *((volatile u32 *)src);
src += 4;
vdest += 4;
n-=4;
}
while(n) {
*((volatile u8 *)vdest) = *((u8 *)src);
src++;
vdest++;
n--;
}
__asm__ __volatile__ ("sync" : : : "memory");
}
#undef EEH_CHECK_ALIGN
static inline u8 eeh_inb(unsigned long port)
{
u8 val;
val = in_8((u8 __iomem *)(port+pci_io_base));
if (EEH_POSSIBLE_ERROR(val, u8))
return eeh_check_failure((void __iomem *)(port), val);
return val;
}
static inline void eeh_outb(u8 val, unsigned long port)
{
out_8((u8 __iomem *)(port+pci_io_base), val);
}
static inline u16 eeh_inw(unsigned long port)
{
u16 val;
val = in_le16((u16 __iomem *)(port+pci_io_base));
if (EEH_POSSIBLE_ERROR(val, u16))
return eeh_check_failure((void __iomem *)(port), val);
return val;
}
static inline void eeh_outw(u16 val, unsigned long port)
{
out_le16((u16 __iomem *)(port+pci_io_base), val);
}
static inline u32 eeh_inl(unsigned long port)
{
u32 val;
val = in_le32((u32 __iomem *)(port+pci_io_base));
if (EEH_POSSIBLE_ERROR(val, u32))
return eeh_check_failure((void __iomem *)(port), val);
return val;
}
static inline void eeh_outl(u32 val, unsigned long port)
{
out_le32((u32 __iomem *)(port+pci_io_base), val);
}
/* in-string eeh macros */
static inline void eeh_insb(unsigned long port, void * buf, int ns)
{
_insb((u8 __iomem *)(port+pci_io_base), buf, ns);
if (EEH_POSSIBLE_ERROR((*(((u8*)buf)+ns-1)), u8))
eeh_check_failure((void __iomem *)(port), *(u8*)buf);
}
static inline void eeh_insw_ns(unsigned long port, void * buf, int ns)
{
_insw_ns((u16 __iomem *)(port+pci_io_base), buf, ns);
if (EEH_POSSIBLE_ERROR((*(((u16*)buf)+ns-1)), u16))
eeh_check_failure((void __iomem *)(port), *(u16*)buf);
}
static inline void eeh_insl_ns(unsigned long port, void * buf, int nl)
{
_insl_ns((u32 __iomem *)(port+pci_io_base), buf, nl);
if (EEH_POSSIBLE_ERROR((*(((u32*)buf)+nl-1)), u32))
eeh_check_failure((void __iomem *)(port), *(u32*)buf);
}
#endif /* __KERNEL__ */
#endif /* _PPC64_EEH_H */