From 997cde2a222091270ce0c276e567b68e5615f577 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 13 Jun 2017 22:45:47 +0900 Subject: mtd: nand: denali: skip driver internal bounce buffer when possible 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 Signed-off-by: Boris Brezillon --- drivers/mtd/nand/denali.c | 38 ++++++++++++-------------------------- 1 file changed, 12 insertions(+), 26 deletions(-) (limited to 'drivers/mtd') diff --git a/drivers/mtd/nand/denali.c b/drivers/mtd/nand/denali.c index e8d8e6c6f45e..ec5fc8da5f9a 100644 --- a/drivers/mtd/nand/denali.c +++ b/drivers/mtd/nand/denali.c @@ -600,12 +600,16 @@ 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) { /* @@ -636,7 +640,7 @@ 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); @@ -822,12 +826,10 @@ 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) @@ -931,10 +933,8 @@ 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) @@ -1374,14 +1374,8 @@ 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; } /* @@ -1471,16 +1465,8 @@ EXPORT_SYMBOL(denali_init); void denali_remove(struct denali_nand_info *denali) { struct mtd_info *mtd = nand_to_mtd(&denali->nand); - /* - * Pre-compute DMA buffer size to avoid any problems in case - * nand_release() ever changes in a way that mtd->writesize and - * mtd->oobsize are not reliable after this call. - */ - int bufsize = mtd->writesize + mtd->oobsize; nand_release(mtd); denali_disable_irq(denali); - dma_unmap_single(denali->dev, denali->dma_addr, bufsize, - DMA_BIDIRECTIONAL); } EXPORT_SYMBOL(denali_remove); -- cgit v1.2.3