Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754220AbdGSLve (ORCPT ); Wed, 19 Jul 2017 07:51:34 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:35190 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753814AbdGSLvb (ORCPT ); Wed, 19 Jul 2017 07:51:31 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 66C8361780 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=absahu@codeaurora.org From: Abhishek Sahu To: dwmw2@infradead.org, computersforpeace@gmail.com, boris.brezillon@free-electrons.com, marek.vasut@gmail.com, richard@nod.at, cyrille.pitchen@wedev4u.fr, robh+dt@kernel.org, mark.rutland@arm.com Cc: linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, andy.gross@linaro.org, architt@codeaurora.org, sricharan@codeaurora.org, Abhishek Sahu Subject: [PATCH v2 15/25] mtd: nand: qcom: DMA mapping support for register read buffer Date: Wed, 19 Jul 2017 17:18:03 +0530 Message-Id: <1500464893-11352-16-git-send-email-absahu@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1500464893-11352-1-git-send-email-absahu@codeaurora.org> References: <1500464893-11352-1-git-send-email-absahu@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4547 Lines: 127 The EBI2 NAND directly remaps register read buffer with dma_map_sg. The QPIC NAND will give register read buffer in its command descriptor and the command descriptor will be mapped with dma_map_sg instead of register read buffer. This command descriptor will contain the dma address of the register read buffer. This patch adds the DMA mapping support for register read buffer. This buffer will be DMA mapped during allocation time. Before starting of any operation, this buffer will be synced for device operation and after operation completion, it will be synced for CPU. Signed-off-by: Abhishek Sahu --- drivers/mtd/nand/qcom_nandc.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/drivers/mtd/nand/qcom_nandc.c b/drivers/mtd/nand/qcom_nandc.c index cb2b245..f49c3da 100644 --- a/drivers/mtd/nand/qcom_nandc.c +++ b/drivers/mtd/nand/qcom_nandc.c @@ -229,6 +229,7 @@ struct nandc_regs { * by upper layers directly * @buf_size/count/start: markers for chip->read_buf/write_buf functions * @reg_read_buf: local buffer for reading back registers via DMA + * @reg_read_buf_phys: contains dma address for register read buffer * @reg_read_pos: marker for data read in reg_read_buf * * @regs: a contiguous chunk of memory for DMA register @@ -271,6 +272,7 @@ struct qcom_nand_controller { int buf_start; __le32 *reg_read_buf; + dma_addr_t reg_read_buf_phys; int reg_read_pos; struct nandc_regs *regs; @@ -363,6 +365,24 @@ static inline void nandc_write(struct qcom_nand_controller *nandc, int offset, iowrite32(val, nandc->base + offset); } +static inline void nandc_read_buffer_sync(struct qcom_nand_controller *nandc, + bool is_cpu) +{ + if (!nandc->props->is_bam) + return; + + if (is_cpu) + dma_sync_single_for_cpu(nandc->dev, nandc->reg_read_buf_phys, + MAX_REG_RD * + sizeof(*nandc->reg_read_buf), + DMA_FROM_DEVICE); + else + dma_sync_single_for_device(nandc->dev, nandc->reg_read_buf_phys, + MAX_REG_RD * + sizeof(*nandc->reg_read_buf), + DMA_FROM_DEVICE); +} + static __le32 *offset_to_nandc_reg(struct nandc_regs *regs, int offset) { switch (offset) { @@ -847,6 +867,7 @@ static void free_descs(struct qcom_nand_controller *nandc) static void clear_read_regs(struct qcom_nand_controller *nandc) { nandc->reg_read_pos = 0; + nandc_read_buffer_sync(nandc, false); } static void pre_command(struct qcom_nand_host *host, int command) @@ -876,6 +897,7 @@ static void parse_erase_write_errors(struct qcom_nand_host *host, int command) int i; num_cw = command == NAND_CMD_PAGEPROG ? ecc->steps : 1; + nandc_read_buffer_sync(nandc, true); for (i = 0; i < num_cw; i++) { u32 flash_status = le32_to_cpu(nandc->reg_read_buf[i]); @@ -897,6 +919,7 @@ static void post_command(struct qcom_nand_host *host, int command) switch (command) { case NAND_CMD_READID: + nandc_read_buffer_sync(nandc, true); memcpy(nandc->data_buffer, nandc->reg_read_buf, nandc->buf_count); break; @@ -1060,6 +1083,7 @@ static int parse_read_errors(struct qcom_nand_host *host, u8 *data_buf, int i; buf = (struct read_stats *)nandc->reg_read_buf; + nandc_read_buffer_sync(nandc, true); for (i = 0; i < ecc->steps; i++, buf++) { u32 flash, buffer, erased_cw; @@ -1996,6 +2020,16 @@ static int qcom_nandc_alloc(struct qcom_nand_controller *nandc) return -ENOMEM; if (nandc->props->is_bam) { + nandc->reg_read_buf_phys = + dma_map_single(nandc->dev, nandc->reg_read_buf, + MAX_REG_RD * + sizeof(*nandc->reg_read_buf), + DMA_FROM_DEVICE); + if (dma_mapping_error(nandc->dev, nandc->reg_read_buf_phys)) { + dev_err(nandc->dev, "failed to DMA MAP reg buffer\n"); + return -EIO; + } + nandc->tx_chan = dma_request_slave_channel(nandc->dev, "tx"); if (!nandc->tx_chan) { dev_err(nandc->dev, "failed to request tx channel\n"); @@ -2033,6 +2067,12 @@ static int qcom_nandc_alloc(struct qcom_nand_controller *nandc) static void qcom_nandc_unalloc(struct qcom_nand_controller *nandc) { if (nandc->props->is_bam) { + if (!dma_mapping_error(nandc->dev, nandc->reg_read_buf_phys)) + dma_unmap_single(nandc->dev, nandc->reg_read_buf_phys, + MAX_REG_RD * + sizeof(*nandc->reg_read_buf), + DMA_FROM_DEVICE); + if (nandc->tx_chan) dma_release_channel(nandc->tx_chan); -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation