From patchwork Mon Sep 7 13:07:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roja Rani Yarubandi X-Patchwork-Id: 254791 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57C92C433E2 for ; Mon, 7 Sep 2020 13:10:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0BA86215A4 for ; Mon, 7 Sep 2020 13:09:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729368AbgIGNIu (ORCPT ); Mon, 7 Sep 2020 09:08:50 -0400 Received: from alexa-out.qualcomm.com ([129.46.98.28]:41689 "EHLO alexa-out.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729418AbgIGNIj (ORCPT ); Mon, 7 Sep 2020 09:08:39 -0400 Received: from ironmsg08-lv.qualcomm.com ([10.47.202.152]) by alexa-out.qualcomm.com with ESMTP; 07 Sep 2020 06:08:15 -0700 Received: from ironmsg02-blr.qualcomm.com ([10.86.208.131]) by ironmsg08-lv.qualcomm.com with ESMTP/TLS/AES256-SHA; 07 Sep 2020 06:08:13 -0700 Received: from c-rojay-linux.qualcomm.com ([10.206.21.80]) by ironmsg02-blr.qualcomm.com with ESMTP; 07 Sep 2020 18:37:35 +0530 Received: by c-rojay-linux.qualcomm.com (Postfix, from userid 88981) id C17E920F7; Mon, 7 Sep 2020 18:37:33 +0530 (IST) From: Roja Rani Yarubandi To: wsa@kernel.org Cc: swboyd@chromium.org, dianders@chromium.org, saiprakash.ranjan@codeaurora.org, gregkh@linuxfoundation.org, mka@chromium.org, akashast@codeaurora.org, msavaliy@qti.qualcomm.com, skakit@codeaurora.org, rnayak@codeaurora.org, agross@kernel.org, bjorn.andersson@linaro.org, linux-arm-msm@vger.kernel.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, sumit.semwal@linaro.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, Roja Rani Yarubandi Subject: [PATCH V3] i2c: i2c-qcom-geni: Add shutdown callback for i2c Date: Mon, 7 Sep 2020 18:37:31 +0530 Message-Id: <20200907130731.2607-1-rojay@codeaurora.org> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org If the hardware is still accessing memory after SMMU translation is disabled (as part of smmu shutdown callback), then the IOVAs (I/O virtual address) which it was using will go on the bus as the physical addresses which will result in unknown crashes like NoC/interconnect errors. So, implement shutdown callback to i2c driver to stop on-going transfer and unmap DMA mappings during system "reboot" or "shutdown". Store DMA mapping data in geni_i2c_dev struct to enhance DMA mapping data scope. For example during shutdown callback to unmap DMA mapping, this stored DMA mapping data can be used to call geni_se_tx_dma_unprep and geni_se_rx_dma_unprep functions. Fixes: 37692de5d523 ("i2c: i2c-qcom-geni: Add bus driver for the Qualcomm GENI I2C controller") Signed-off-by: Roja Rani Yarubandi --- Changes in V2: - As per Stephen's comments added seperate function for stop transfer, fixed minor nitpicks. - As per Stephen's comments, changed commit text. Changes in V3: - As per Stephen's comments, squashed patch 1 into patch 2, added Fixes tag. - As per Akash's comments, included FIFO case in stop_xfer, fixed minor nitpicks. drivers/i2c/busses/i2c-qcom-geni.c | 70 +++++++++++++++++++++++++++--- include/linux/qcom-geni-se.h | 5 +++ 2 files changed, 69 insertions(+), 6 deletions(-) diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index dead5db3315a..b3609760909f 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -86,6 +86,9 @@ struct geni_i2c_dev { u32 clk_freq_out; const struct geni_i2c_clk_fld *clk_fld; int suspended; + dma_addr_t tx_dma; + dma_addr_t rx_dma; + size_t xfer_len; }; struct geni_i2c_err_log { @@ -352,12 +355,12 @@ static void geni_i2c_tx_fsm_rst(struct geni_i2c_dev *gi2c) static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, u32 m_param) { - dma_addr_t rx_dma; unsigned long time_left; void *dma_buf = NULL; struct geni_se *se = &gi2c->se; size_t len = msg->len; + gi2c->xfer_len = len; if (!of_machine_is_compatible("lenovo,yoga-c630")) dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); @@ -368,7 +371,7 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, writel_relaxed(len, se->base + SE_I2C_RX_TRANS_LEN); - if (dma_buf && geni_se_rx_dma_prep(se, dma_buf, len, &rx_dma)) { + if (dma_buf && geni_se_rx_dma_prep(se, dma_buf, len, &gi2c->rx_dma)) { geni_se_select_mode(se, GENI_SE_FIFO); i2c_put_dma_safe_msg_buf(dma_buf, msg, false); dma_buf = NULL; @@ -384,7 +387,8 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, if (dma_buf) { if (gi2c->err) geni_i2c_rx_fsm_rst(gi2c); - geni_se_rx_dma_unprep(se, rx_dma, len); + geni_se_rx_dma_unprep(se, gi2c->rx_dma, len); + gi2c->rx_dma = (dma_addr_t)NULL; i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err); } @@ -394,12 +398,12 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, u32 m_param) { - dma_addr_t tx_dma; unsigned long time_left; void *dma_buf = NULL; struct geni_se *se = &gi2c->se; size_t len = msg->len; + gi2c->xfer_len = len; if (!of_machine_is_compatible("lenovo,yoga-c630")) dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); @@ -410,7 +414,7 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, writel_relaxed(len, se->base + SE_I2C_TX_TRANS_LEN); - if (dma_buf && geni_se_tx_dma_prep(se, dma_buf, len, &tx_dma)) { + if (dma_buf && geni_se_tx_dma_prep(se, dma_buf, len, &gi2c->tx_dma)) { geni_se_select_mode(se, GENI_SE_FIFO); i2c_put_dma_safe_msg_buf(dma_buf, msg, false); dma_buf = NULL; @@ -429,7 +433,8 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, if (dma_buf) { if (gi2c->err) geni_i2c_tx_fsm_rst(gi2c); - geni_se_tx_dma_unprep(se, tx_dma, len); + geni_se_tx_dma_unprep(se, gi2c->tx_dma, len); + gi2c->tx_dma = (dma_addr_t)NULL; i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err); } @@ -479,6 +484,51 @@ static int geni_i2c_xfer(struct i2c_adapter *adap, return ret; } +static void geni_i2c_stop_xfer(struct geni_i2c_dev *gi2c) +{ + int ret; + u32 dma; + u32 val; + u32 geni_status; + struct geni_se *se = &gi2c->se; + + ret = pm_runtime_get_sync(gi2c->se.dev); + if (ret < 0) { + dev_err(gi2c->se.dev, "Failed to resume device: %d\n", ret); + return; + } + + geni_status = readl_relaxed(gi2c->se.base + SE_GENI_STATUS); + if (geni_status & M_GENI_CMD_ACTIVE) { + geni_i2c_abort_xfer(gi2c); + dma = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN); + if (dma) { + val = readl_relaxed(gi2c->se.base + SE_DMA_DEBUG_REG0); + if (val & DMA_TX_ACTIVE) { + gi2c->cur_wr = 0; + if (gi2c->err) + geni_i2c_tx_fsm_rst(gi2c); + if (gi2c->tx_dma) { + geni_se_tx_dma_unprep(se, + gi2c->tx_dma, gi2c->xfer_len); + gi2c->tx_dma = (dma_addr_t)NULL; + } + } else if (val & DMA_RX_ACTIVE) { + gi2c->cur_rd = 0; + if (gi2c->err) + geni_i2c_rx_fsm_rst(gi2c); + if (gi2c->rx_dma) { + geni_se_rx_dma_unprep(se, + gi2c->rx_dma, gi2c->xfer_len); + gi2c->rx_dma = (dma_addr_t)NULL; + } + } + } + } + + pm_runtime_put_sync_suspend(gi2c->se.dev); +} + static u32 geni_i2c_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); @@ -630,6 +680,13 @@ static int geni_i2c_remove(struct platform_device *pdev) return 0; } +static void geni_i2c_shutdown(struct platform_device *pdev) +{ + struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev); + + geni_i2c_stop_xfer(gi2c); +} + static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev) { int ret; @@ -694,6 +751,7 @@ MODULE_DEVICE_TABLE(of, geni_i2c_dt_match); static struct platform_driver geni_i2c_driver = { .probe = geni_i2c_probe, .remove = geni_i2c_remove, + .shutdown = geni_i2c_shutdown, .driver = { .name = "geni_i2c", .pm = &geni_i2c_pm_ops, diff --git a/include/linux/qcom-geni-se.h b/include/linux/qcom-geni-se.h index 8f385fbe5a0e..7279d8b3b04c 100644 --- a/include/linux/qcom-geni-se.h +++ b/include/linux/qcom-geni-se.h @@ -96,6 +96,7 @@ struct geni_se { #define SE_DMA_RX_FSM_RST 0xd58 #define SE_HW_PARAM_0 0xe24 #define SE_HW_PARAM_1 0xe28 +#define SE_DMA_DEBUG_REG0 0xe40 /* GENI_FORCE_DEFAULT_REG fields */ #define FORCE_DEFAULT BIT(0) @@ -226,6 +227,10 @@ struct geni_se { #define RX_GENI_CANCEL_IRQ BIT(11) #define RX_GENI_GP_IRQ_EXT GENMASK(13, 12) +/* SE_DMA_DEBUG_REG0 Register fields */ +#define DMA_TX_ACTIVE BIT(0) +#define DMA_RX_ACTIVE BIT(1) + /* SE_HW_PARAM_0 fields */ #define TX_FIFO_WIDTH_MSK GENMASK(29, 24) #define TX_FIFO_WIDTH_SHFT 24