From e615bf5b5519862ab66172f4dec7455d6543a578 Mon Sep 17 00:00:00 2001 From: Myron Stowe Date: Fri, 20 Jan 2012 19:13:24 -0700 Subject: 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 04c25997c97, 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 Signed-off-by: Len Brown --- drivers/acpi/osl.c | 116 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) (limited to 'drivers/acpi/osl.c') diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index fcc12d842bc..5498a6d88ba 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -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) -- cgit v1.2.3