From 24e9d0b96dac5503c0b6f034d553030c604228a7 Mon Sep 17 00:00:00 2001
From: Ralf Baechle <ralf@linux-mips.org>
Date: Tue, 10 Jul 2007 17:32:56 +0100
Subject: [MIPS] Hook for platforms to define cachability of /dev/mem regions
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
---
arch/mips/mm/cache.c | 10 ++++++++++
drivers/char/mem.c | 7 +++++++
2 files changed, 17 insertions(+)
diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index abf99b1eba..81f925a9a7 100644
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -6,6 +6,8 @@
* Copyright (C) 1994 - 2003, 07 by Ralf Baechle (ralf@linux-mips.org)
* Copyright (C) 2007 MIPS Technologies, Inc.
*/
+#include <linux/fs.h>
+#include <linux/fcntl.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
@@ -164,3 +166,11 @@ void __init cpu_cache_init(void)
panic(cache_panic);
}
+
+int __weak __uncached_access(struct file *file, unsigned long addr)
+{
+ if (file->f_flags & O_SYNC)
+ return 1;
+
+ return addr >= __pa(high_memory);
+}
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index cc9a9d0df9..7e082bceed 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -75,6 +75,13 @@ static inline int uncached_access(struct file *file, unsigned long addr)
* On ia64, we ignore O_SYNC because we cannot tolerate memory attribute aliases.
*/
return !(efi_mem_attributes(addr) & EFI_MEMORY_WB);
+#elif defined(CONFIG_MIPS)
+ {
+ extern int __uncached_access(struct file *file,
+ unsigned long addr);
+
+ return __uncached_access(file, addr);
+ }
#else
/*
* Accessing memory above the top the kernel knows about or through a file pointer
--
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