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Diffstat (limited to 'arch/arm/include/asm/io.h')
-rw-r--r--arch/arm/include/asm/io.h75
1 files changed, 58 insertions, 17 deletions
diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
index 1c3938f26beb..485982084fe9 100644
--- a/arch/arm/include/asm/io.h
+++ b/arch/arm/include/asm/io.h
@@ -140,16 +140,11 @@ static inline u32 __raw_readl(const volatile void __iomem *addr)
* The _caller variety takes a __builtin_return_address(0) value for
* /proc/vmalloc to use - and should only be used in non-inline functions.
*/
-extern void __iomem *__arm_ioremap_pfn_caller(unsigned long, unsigned long,
- size_t, unsigned int, void *);
extern void __iomem *__arm_ioremap_caller(phys_addr_t, size_t, unsigned int,
void *);
-
extern void __iomem *__arm_ioremap_pfn(unsigned long, unsigned long, size_t, unsigned int);
-extern void __iomem *__arm_ioremap(phys_addr_t, size_t, unsigned int);
extern void __iomem *__arm_ioremap_exec(phys_addr_t, size_t, bool cached);
extern void __iounmap(volatile void __iomem *addr);
-extern void __arm_iounmap(volatile void __iomem *addr);
extern void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
unsigned int, void *);
@@ -321,21 +316,24 @@ extern void _memset_io(volatile void __iomem *, int, size_t);
static inline void memset_io(volatile void __iomem *dst, unsigned c,
size_t count)
{
- memset((void __force *)dst, c, count);
+ extern void mmioset(void *, unsigned int, size_t);
+ mmioset((void __force *)dst, c, count);
}
#define memset_io(dst,c,count) memset_io(dst,c,count)
static inline void memcpy_fromio(void *to, const volatile void __iomem *from,
size_t count)
{
- memcpy(to, (const void __force *)from, count);
+ extern void mmiocpy(void *, const void *, size_t);
+ mmiocpy(to, (const void __force *)from, count);
}
#define memcpy_fromio(to,from,count) memcpy_fromio(to,from,count)
static inline void memcpy_toio(volatile void __iomem *to, const void *from,
size_t count)
{
- memcpy((void __force *)to, from, count);
+ extern void mmiocpy(void *, const void *, size_t);
+ mmiocpy((void __force *)to, from, count);
}
#define memcpy_toio(to,from,count) memcpy_toio(to,from,count)
@@ -348,18 +346,61 @@ static inline void memcpy_toio(volatile void __iomem *to, const void *from,
#endif /* readl */
/*
- * ioremap and friends.
+ * ioremap() and friends.
+ *
+ * ioremap() takes a resource address, and size. Due to the ARM memory
+ * types, it is important to use the correct ioremap() function as each
+ * mapping has specific properties.
+ *
+ * Function Memory type Cacheability Cache hint
+ * ioremap() Device n/a n/a
+ * ioremap_nocache() Device n/a n/a
+ * ioremap_cache() Normal Writeback Read allocate
+ * ioremap_wc() Normal Non-cacheable n/a
+ * ioremap_wt() Normal Non-cacheable n/a
+ *
+ * All device mappings have the following properties:
+ * - no access speculation
+ * - no repetition (eg, on return from an exception)
+ * - number, order and size of accesses are maintained
+ * - unaligned accesses are "unpredictable"
+ * - writes may be delayed before they hit the endpoint device
*
- * ioremap takes a PCI memory address, as specified in
- * Documentation/io-mapping.txt.
+ * ioremap_nocache() is the same as ioremap() as there are too many device
+ * drivers using this for device registers, and documentation which tells
+ * people to use it for such for this to be any different. This is not a
+ * safe fallback for memory-like mappings, or memory regions where the
+ * compiler may generate unaligned accesses - eg, via inlining its own
+ * memcpy.
*
+ * All normal memory mappings have the following properties:
+ * - reads can be repeated with no side effects
+ * - repeated reads return the last value written
+ * - reads can fetch additional locations without side effects
+ * - writes can be repeated (in certain cases) with no side effects
+ * - writes can be merged before accessing the target
+ * - unaligned accesses can be supported
+ * - ordering is not guaranteed without explicit dependencies or barrier
+ * instructions
+ * - writes may be delayed before they hit the endpoint memory
+ *
+ * The cache hint is only a performance hint: CPUs may alias these hints.
+ * Eg, a CPU not implementing read allocate but implementing write allocate
+ * will provide a write allocate mapping instead.
*/
-#define ioremap(cookie,size) __arm_ioremap((cookie), (size), MT_DEVICE)
-#define ioremap_nocache(cookie,size) __arm_ioremap((cookie), (size), MT_DEVICE)
-#define ioremap_cache(cookie,size) __arm_ioremap((cookie), (size), MT_DEVICE_CACHED)
-#define ioremap_wc(cookie,size) __arm_ioremap((cookie), (size), MT_DEVICE_WC)
-#define ioremap_wt(cookie,size) __arm_ioremap((cookie), (size), MT_DEVICE)
-#define iounmap __arm_iounmap
+void __iomem *ioremap(resource_size_t res_cookie, size_t size);
+#define ioremap ioremap
+#define ioremap_nocache ioremap
+
+void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size);
+#define ioremap_cache ioremap_cache
+
+void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size);
+#define ioremap_wc ioremap_wc
+#define ioremap_wt ioremap_wc
+
+void iounmap(volatile void __iomem *iomem_cookie);
+#define iounmap iounmap
/*
* io{read,write}{16,32}be() macros