From 97bf85d784fbed485e652eb907589ad0d5cb7262 Mon Sep 17 00:00:00 2001 From: Daniel Hellstrom Date: Fri, 28 Mar 2008 20:40:19 +0100 Subject: MTD/CFI: flash_read64 is defined a weak function (for SPARC) SPARC has implemented __raw_readq, it reads 64-bit from any 32-bit address. SPARC CPUs implement flash_read64 which calls __raw_readq. For current SPARC architectures (LEON2 and LEON3) each read from the FLASH must lead to a cache miss. This is because FLASH can not be set non-cacheable since program code resides there, and alternatively disabling cache is poor from performance view, or doing a cache flush between each read is even poorer. Forcing a cache miss on a SPARC is done by a special instruction "lda" - load alternative space, the alternative space number (ASI) is processor implementation spcific and can be found by including . Signed-off-by: Daniel Hellstrom --- drivers/mtd/cfi_flash.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/mtd/cfi_flash.c') diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c index 3f8911e..40fddcd 100644 --- a/drivers/mtd/cfi_flash.c +++ b/drivers/mtd/cfi_flash.c @@ -239,12 +239,14 @@ static u32 flash_read32(void *addr) return __raw_readl(addr); } -static u64 flash_read64(void *addr) +static u64 __flash_read64(void *addr) { /* No architectures currently implement __raw_readq() */ return *(volatile u64 *)addr; } +u64 flash_read64(void *addr)__attribute__((weak, alias("__flash_read64"))); + /*----------------------------------------------------------------------- */ #if defined(CFG_ENV_IS_IN_FLASH) || defined(CFG_ENV_ADDR_REDUND) || (CFG_MONITOR_BASE >= CFG_FLASH_BASE) -- cgit v1.1