From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Agner Date: Wed, 8 Apr 2015 16:44:34 +0200 Subject: [U-Boot] [PATCH v2 1/8] mtd: vf610_nfc: remove caching of page in buffer In-Reply-To: <1428504281-30214-1-git-send-email-stefan@agner.ch> References: <1428504281-30214-1-git-send-email-stefan@agner.ch> Message-ID: <1428504281-30214-2-git-send-email-stefan@agner.ch> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de To improve performance we remember the current page in the buffer and avoid reading it twice. This implicit page cache increases complexity while does not increase performance in real world cases. This patch removes that feature. Acked-by: Bill Pringlemeir Signed-off-by: Stefan Agner --- drivers/mtd/nand/vf610_nfc.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) diff --git a/drivers/mtd/nand/vf610_nfc.c b/drivers/mtd/nand/vf610_nfc.c index d98dd28..fa0bb9d 100644 --- a/drivers/mtd/nand/vf610_nfc.c +++ b/drivers/mtd/nand/vf610_nfc.c @@ -147,7 +147,6 @@ struct vf610_nfc { uint column; int spareonly; int page_sz; - int page; /* Status and ID are in alternate locations. */ int alt_buf; #define ALT_BUF_ID 1 @@ -347,7 +346,6 @@ static void vf610_nfc_command(struct mtd_info *mtd, unsigned command, switch (command) { case NAND_CMD_PAGEPROG: - nfc->page = -1; vf610_nfc_transfer_size(nfc->regs, nfc->page_sz); vf610_nfc_send_commands(nfc->regs, NAND_CMD_SEQIN, command, PROGRAM_PAGE_CMD_CODE); @@ -367,10 +365,6 @@ static void vf610_nfc_command(struct mtd_info *mtd, unsigned command, case NAND_CMD_SEQIN: /* Pre-read for partial writes. */ case NAND_CMD_READ0: column = 0; - /* Already read? */ - if (nfc->page == page) - return; - nfc->page = page; vf610_nfc_transfer_size(nfc->regs, nfc->page_sz); vf610_nfc_send_commands(nfc->regs, NAND_CMD_READ0, NAND_CMD_READSTART, READ_PAGE_CMD_CODE); @@ -378,7 +372,6 @@ static void vf610_nfc_command(struct mtd_info *mtd, unsigned command, break; case NAND_CMD_ERASE1: - nfc->page = -1; vf610_nfc_transfer_size(nfc->regs, 0); vf610_nfc_send_commands(nfc->regs, command, NAND_CMD_ERASE2, ERASE_CMD_CODE); @@ -532,10 +525,8 @@ static inline int vf610_nfc_correct_data(struct mtd_info *mtd, u_char *dat) flip = count_written_bits(dat, nfc->chip.ecc.size, ecc_count); /* ECC failed. */ - if (flip > ecc_count) { - nfc->page = -1; + if (flip > ecc_count) return -1; - } /* Erased page. */ memset(dat, 0xff, nfc->chip.ecc.size); -- 2.3.5