[Linaro-acpi] [PATCH 06/38] acpi: fix acpi_os_ioremap for arm64

al.stone at linaro.org al.stone at linaro.org
Thu Nov 6 03:32:25 UTC 2014

From: Mark Salter <msalter at redhat.com>

The acpi_os_ioremap() function may be used to map normal RAM or IO
regions. The current implementation simply uses ioremap_cache(). This
will work for some architectures, but arm64 ioremap_cache() cannot be
used to map IO regions which don't support caching. So for arm64, use
ioremap() for non-RAM regions.

Signed-off-by: Mark Salter <msalter at redhat.com>
 include/acpi/acpi_io.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/acpi/acpi_io.h b/include/acpi/acpi_io.h
index 444671e..9d573db 100644
--- a/include/acpi/acpi_io.h
+++ b/include/acpi/acpi_io.h
@@ -1,11 +1,17 @@
 #ifndef _ACPI_IO_H_
 #define _ACPI_IO_H_
+#include <linux/mm.h>
 #include <linux/io.h>
 static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys,
 					    acpi_size size)
+#ifdef CONFIG_ARM64
+	if (!page_is_ram(phys >> PAGE_SHIFT))
+		return ioremap(phys, size);
        return ioremap_cache(phys, size);

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