From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932945AbdC3ISE (ORCPT ); Thu, 30 Mar 2017 04:18:04 -0400 Received: from conuserg-09.nifty.com ([210.131.2.76]:45138 "EHLO conuserg-09.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932763AbdC3ISD (ORCPT ); Thu, 30 Mar 2017 04:18:03 -0400 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-09.nifty.com v2U8FQ9i018607 X-Nifty-SrcIP: [153.142.97.92] From: Masahiro Yamada To: linux-mtd@lists.infradead.org Cc: linux-kernel@vger.kernel.org, Boris Brezillon , David Woodhouse , Marek Vasut , Dinh Nguyen , Artem Bityutskiy , Graham Moore , Enrico Jorns , Chuanxiao Dong , Masami Hiramatsu , Jassi Brar , Masahiro Yamada Subject: [PATCH v3 35/37] mtd: nand: denali: skip driver internal bounce buffer when possible Date: Thu, 30 Mar 2017 17:15:06 +0900 Message-Id: <1490861708-27813-5-git-send-email-yamada.masahiro@socionext.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1490861708-27813-1-git-send-email-yamada.masahiro@socionext.com> References: <1490861708-27813-1-git-send-email-yamada.masahiro@socionext.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org For ecc->read_page() and ecc->write_page(), it is possible to call dma_map_single() against the given buffer. This bypasses the driver internal bounce buffer and save the memcpy(). Signed-off-by: Masahiro Yamada denali: set buf_align 16 --- Changes in v3: - Set chip->buf_align to 16 Changes in v2: - Newly added drivers/mtd/nand/denali.c | 29 ++++++++++++----------------- 1 file changed, 12 insertions(+), 17 deletions(-) diff --git a/drivers/mtd/nand/denali.c b/drivers/mtd/nand/denali.c index 9ee0f30..87e5f0f 100644 --- a/drivers/mtd/nand/denali.c +++ b/drivers/mtd/nand/denali.c @@ -646,12 +646,16 @@ static int denali_pio_xfer(struct denali_nand_info *denali, void *buf, static int denali_dma_xfer(struct denali_nand_info *denali, void *buf, size_t size, int page, int raw, int write) { - dma_addr_t dma_addr = denali->dma_addr; + dma_addr_t dma_addr; uint32_t irq_mask, irq_status, ecc_err_mask; enum dma_data_direction dir = write ? DMA_TO_DEVICE : DMA_FROM_DEVICE; int ret = 0; - dma_sync_single_for_device(denali->dev, dma_addr, size, dir); + dma_addr = dma_map_single(denali->dev, buf, size, dir); + if (dma_mapping_error(denali->dev, dma_addr)) { + dev_dbg(denali->dev, "Failed to DMA-map buffer. Trying PIO.\n"); + return denali_pio_xfer(denali, buf, size, page, raw, write); + } if (write) { irq_mask = INTR__DMA_CMD_COMP | INTR__PROGRAM_FAIL; @@ -677,7 +681,7 @@ static int denali_dma_xfer(struct denali_nand_info *denali, void *buf, ret = -EBADMSG; denali_enable_dma(denali, false); - dma_sync_single_for_cpu(denali->dev, dma_addr, size, dir); + dma_unmap_single(denali->dev, dma_addr, size, dir); if (irq_status & INTR__ERASED_PAGE) memset(buf, 0xff, size); @@ -853,12 +857,10 @@ static int denali_read_page(struct mtd_info *mtd, struct nand_chip *chip, int stat = 0; int ret; - ret = denali_data_xfer(denali, denali->buf, mtd->writesize, page, 0, 0); + ret = denali_data_xfer(denali, buf, mtd->writesize, page, 0, 0); if (ret && ret != -EBADMSG) return ret; - memcpy(buf, denali->buf, mtd->writesize); - if (denali->caps & DENALI_CAP_HW_ECC_FIXUP) stat = denali_hw_ecc_fixup(mtd, denali, &uncor_ecc_flags); else if (ret == -EBADMSG) @@ -962,10 +964,8 @@ static int denali_write_page(struct mtd_info *mtd, struct nand_chip *chip, { struct denali_nand_info *denali = mtd_to_denali(mtd); - memcpy(denali->buf, buf, mtd->writesize); - - return denali_data_xfer(denali, denali->buf, mtd->writesize, page, - 0, 1); + return denali_data_xfer(denali, (void *)buf, mtd->writesize, + page, 0, 1); } static void denali_select_chip(struct mtd_info *mtd, int chip) @@ -1409,13 +1409,8 @@ int denali_init(struct denali_nand_info *denali) } if (denali->dma_avail) { - denali->dma_addr = dma_map_single(denali->dev, denali->buf, - mtd->writesize + mtd->oobsize, - DMA_BIDIRECTIONAL); - if (dma_mapping_error(denali->dev, denali->dma_addr)) { - dev_info(denali->dev, "Failed to map DMA buffer. Disabling DMA.\n"); - denali->dma_avail = 0; - }; + chip->options |= NAND_USE_BOUNCE_BUFFER; + chip->buf_align = 16; } /* -- 2.7.4