On Mon, 2015-02-02 at 23:14 +0100, Rafael J. Wysocki wrote:

On Monday, February 02, 2015 08:45:30 PM Hanjun Guo wrote:

quoted

From: Mark Salter <redacted>

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.

CC: Rafael J Wysocki <redacted>
Signed-off-by: Mark Salter <redacted>
Signed-off-by: Hanjun Guo <redacted>
---
 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);
+#endif

I don't want to see #ifdef CONFIG_ARM64 in this file.

How about something like:

From: Mark Salter <redacted>
Date: Tue, 3 Feb 2015 10:51:16 -0500
Subject: [PATCH] acpi: fix acpi_os_ioremap for arm64

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.

CC: Rafael J Wysocki <redacted>
Signed-off-by: Mark Salter <redacted>
---
 arch/arm64/include/asm/acpi.h | 14 ++++++++++++++
 include/acpi/acpi_io.h        |  3 +++
 2 files changed, 17 insertions(+)

diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h
index ea4d2b3..db82bc3 100644
--- a/arch/arm64/include/asm/acpi.h
+++ b/arch/arm64/include/asm/acpi.h

@@ -14,6 +14,7 @@
 
 #include <linux/irqchip/arm-gic-acpi.h>
 
+#include <linux/mm.h>
 #include <asm/smp_plat.h>
 
 /* Basic configuration for ACPI */

@@ -100,4 +101,17 @@ static inline bool acpi_psci_use_hvc(void) { return false; }
 static inline void acpi_init_cpus(void) { }
 #endif /* CONFIG_ACPI */
 
+/*
+ * ACPI table mapping
+ */
+static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys,
+					    acpi_size size)
+{
+	if (!page_is_ram(phys >> PAGE_SHIFT))
+		return ioremap(phys, size);
+
+       return ioremap_cache(phys, size);
+}
+#define acpi_os_ioremap acpi_os_ioremap
+
 #endif /*_ASM_ACPI_H*/

diff --git a/include/acpi/acpi_io.h b/include/acpi/acpi_io.h
index 444671e..48f504a 100644
--- a/include/acpi/acpi_io.h
+++ b/include/acpi/acpi_io.h

@@ -2,12 +2,15 @@
 #define _ACPI_IO_H_
 
 #include <linux/io.h>
+#include <asm/acpi.h>
 
+#ifndef acpi_os_ioremap
 static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys,
 					    acpi_size size)
 {
        return ioremap_cache(phys, size);
 }
+#endif
 
 void __iomem *__init_refok
 acpi_os_map_iomem(acpi_physical_address phys, acpi_size size);

-- 
1.8.3.1