This commit adds support for reading the D cache line size for armv7 architecture.
The get_dcache_line_size() function is supposed to work in conjunction with memalign call to provide D cache aligned DMA buffers.
Signed-off-by: Lukasz Majewski l.majewski@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com CC: Aneesh V aneesh@ti.com CC: Albert ARIBAUD albert.u.boot@aribaud.net --- Changes for v2: - Weak function get_dcache_line_size added to lib/cache.c for non armv7 architectures Changes for v3: - __BIGGEST_ALIGNMENT__ GCC constant added --- arch/arm/cpu/armv7/cache_v7.c | 14 ++++++++++++++ arch/arm/lib/cache.c | 13 +++++++++++++ include/common.h | 1 + 3 files changed, 28 insertions(+), 0 deletions(-)
diff --git a/arch/arm/cpu/armv7/cache_v7.c b/arch/arm/cpu/armv7/cache_v7.c index 3e1e1bf..ea5a3e4 100644 --- a/arch/arm/cpu/armv7/cache_v7.c +++ b/arch/arm/cpu/armv7/cache_v7.c @@ -246,6 +246,20 @@ static void v7_inval_tlb(void) CP15ISB; }
+/* Read the cache line size (in bytes) */ +int get_dcache_line_size(void) +{ + u32 ccsidr, log2_line_len; + + ccsidr = get_ccsidr(); + log2_line_len = ((ccsidr & CCSIDR_LINE_SIZE_MASK) >> + CCSIDR_LINE_SIZE_OFFSET) + 2; + /* Converting from words to bytes */ + log2_line_len += 2; + + return 1 << log2_line_len; +} + void invalidate_dcache_all(void) { v7_maint_dcache_all(ARMV7_DCACHE_INVAL_ALL); diff --git a/arch/arm/lib/cache.c b/arch/arm/lib/cache.c index 92b61a2..305f070 100644 --- a/arch/arm/lib/cache.c +++ b/arch/arm/lib/cache.c @@ -53,3 +53,16 @@ void __flush_dcache_all(void) } void flush_dcache_all(void) __attribute__((weak, alias("__flush_dcache_all"))); + +/* Default implementation: */ +/* Read the default D CACHE LINE size */ +int __attribute__((weak)) get_dcache_line_size(void) +{ +#if defined(CONFIG_SYS_CACHE_LINE_SIZE) && !defined(CONFIG_SYS_DCACHE_OFF) + return CONFIG_SYS_CACHE_LINE_SIZE; +#else + /* The smallest alignment */ + /* for memalign() is 8 Bytes. */ + return __BIGGEST_ALIGNMENT__; /* Constant defined by GCC compiler */ +#endif +} diff --git a/include/common.h b/include/common.h index 12a1074..b535300 100644 --- a/include/common.h +++ b/include/common.h @@ -622,6 +622,7 @@ void flush_dcache_range(unsigned long start, unsigned long stop); void invalidate_dcache_range(unsigned long start, unsigned long stop); void invalidate_dcache_all(void); void invalidate_icache_all(void); +int get_dcache_line_size(void);
/* arch/$(ARCH)/lib/ticks.S */ unsigned long long get_ticks(void);