From: Daniel Hellstrom Date: Fri, 28 Mar 2008 19:40:19 +0000 (+0100) Subject: MTD/CFI: flash_read64 is defined a weak function (for SPARC) X-Git-Tag: v1.3.3-rc1~118^2 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=97bf85d784fbed485e652eb907589ad0d5cb7262;p=oweals%2Fu-boot.git 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 --- diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c index 3f8911eb87..40fddcddad 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)