diff options
Diffstat (limited to 'arch/ia64/mm/ioremap.c')
| -rw-r--r-- | arch/ia64/mm/ioremap.c | 27 |
1 files changed, 22 insertions, 5 deletions
diff --git a/arch/ia64/mm/ioremap.c b/arch/ia64/mm/ioremap.c index 643ccc6960c..07bd02b6c37 100644 --- a/arch/ia64/mm/ioremap.c +++ b/arch/ia64/mm/ioremap.c @@ -11,6 +11,7 @@ #include <linux/module.h> #include <linux/efi.h> #include <asm/io.h> +#include <asm/meminit.h> static inline void __iomem * __ioremap (unsigned long offset, unsigned long size) @@ -21,16 +22,29 @@ __ioremap (unsigned long offset, unsigned long size) void __iomem * ioremap (unsigned long offset, unsigned long size) { - if (efi_mem_attribute_range(offset, size, EFI_MEMORY_WB)) - return phys_to_virt(offset); + u64 attr; + unsigned long gran_base, gran_size; - if (efi_mem_attribute_range(offset, size, EFI_MEMORY_UC)) + /* + * For things in kern_memmap, we must use the same attribute + * as the rest of the kernel. For more details, see + * Documentation/ia64/aliasing.txt. + */ + attr = kern_mem_attribute(offset, size); + if (attr & EFI_MEMORY_WB) + return phys_to_virt(offset); + else if (attr & EFI_MEMORY_UC) return __ioremap(offset, size); /* - * Someday this should check ACPI resources so we - * can do the right thing for hot-plugged regions. + * Some chipsets don't support UC access to memory. If + * WB is supported for the whole granule, we prefer that. */ + gran_base = GRANULEROUNDDOWN(offset); + gran_size = GRANULEROUNDUP(offset + size) - gran_base; + if (efi_mem_attribute(gran_base, gran_size) & EFI_MEMORY_WB) + return phys_to_virt(offset); + return __ioremap(offset, size); } EXPORT_SYMBOL(ioremap); @@ -38,6 +52,9 @@ EXPORT_SYMBOL(ioremap); void __iomem * ioremap_nocache (unsigned long offset, unsigned long size) { + if (kern_mem_attribute(offset, size) & EFI_MEMORY_WB) + return 0; + return __ioremap(offset, size); } EXPORT_SYMBOL(ioremap_nocache); |