ACPI, APEI: Add 64-bit read/write support for APEI on i386

Base ACPI (CA) currently does not support atomic 64-bit reads and writes
(acpi_read() and acpi_write() split 64-bit loads/stores into two
32-bit transfers) yet APEI expects 64-bit transfer capability, even
when running on 32-bit systems.

This patch implements 64-bit read and write routines for APEI usage.

This patch re-factors similar functionality introduced in commit
04c25997c9, bringing it into the ACPI subsystem in preparation for
removing ./drivers/acpi/atomicio.[ch].  In the implementation I have
replicated acpi_os_read_memory() and acpi_os_write_memory(), creating
64-bit versions for APEI to utilize, as opposed to something more
elegant.  My thinking is that we should attempt to see if we can get
ACPI's CA/OSL changed so that the existing acpi_read() and acpi_write()
interfaces are natively 64-bit capable and then subsequently remove the
replication.

Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Myron Stowe
2012-01-20 19:13:24 -07:00
committed by Len Brown
parent dcd6c92267
commit e615bf5b55
3 changed files with 124 additions and 31 deletions

View File

@@ -710,6 +710,67 @@ acpi_os_read_memory(acpi_physical_address phys_addr, u32 * value, u32 width)
return AE_OK;
}
#ifdef readq
static inline u64 read64(const volatile void __iomem *addr)
{
return readq(addr);
}
#else
static inline u64 read64(const volatile void __iomem *addr)
{
u64 l, h;
l = readl(addr);
h = readl(addr+4);
return l | (h << 32);
}
#endif
acpi_status
acpi_os_read_memory64(acpi_physical_address phys_addr, u64 *value, u32 width)
{
void __iomem *virt_addr;
unsigned int size = width / 8;
bool unmap = false;
u64 dummy;
rcu_read_lock();
virt_addr = acpi_map_vaddr_lookup(phys_addr, size);
if (!virt_addr) {
rcu_read_unlock();
virt_addr = acpi_os_ioremap(phys_addr, size);
if (!virt_addr)
return AE_BAD_ADDRESS;
unmap = true;
}
if (!value)
value = &dummy;
switch (width) {
case 8:
*(u8 *) value = readb(virt_addr);
break;
case 16:
*(u16 *) value = readw(virt_addr);
break;
case 32:
*(u32 *) value = readl(virt_addr);
break;
case 64:
*(u64 *) value = read64(virt_addr);
break;
default:
BUG();
}
if (unmap)
iounmap(virt_addr);
else
rcu_read_unlock();
return AE_OK;
}
acpi_status
acpi_os_write_memory(acpi_physical_address phys_addr, u32 value, u32 width)
{
@@ -749,6 +810,61 @@ acpi_os_write_memory(acpi_physical_address phys_addr, u32 value, u32 width)
return AE_OK;
}
#ifdef writeq
static inline void write64(u64 val, volatile void __iomem *addr)
{
writeq(val, addr);
}
#else
static inline void write64(u64 val, volatile void __iomem *addr)
{
writel(val, addr);
writel(val>>32, addr+4);
}
#endif
acpi_status
acpi_os_write_memory64(acpi_physical_address phys_addr, u64 value, u32 width)
{
void __iomem *virt_addr;
unsigned int size = width / 8;
bool unmap = false;
rcu_read_lock();
virt_addr = acpi_map_vaddr_lookup(phys_addr, size);
if (!virt_addr) {
rcu_read_unlock();
virt_addr = acpi_os_ioremap(phys_addr, size);
if (!virt_addr)
return AE_BAD_ADDRESS;
unmap = true;
}
switch (width) {
case 8:
writeb(value, virt_addr);
break;
case 16:
writew(value, virt_addr);
break;
case 32:
writel(value, virt_addr);
break;
case 64:
write64(value, virt_addr);
break;
default:
BUG();
}
if (unmap)
iounmap(virt_addr);
else
rcu_read_unlock();
return AE_OK;
}
acpi_status
acpi_os_read_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
u64 *value, u32 width)