From: Roja Rani Yarubandi <rojay@codeaurora.org>
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 <rojay@codeaurora.org>
Subject: [PATCH 2/2] i2c: i2c-qcom-geni: Add shutdown callback for i2c
Date: Fri, 14 Aug 2020 15:25:40 +0530 [thread overview]
Message-ID: <20200814095540.32115-3-rojay@codeaurora.org> (raw)
In-Reply-To: <20200814095540.32115-1-rojay@codeaurora.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, adding shutdown callback to i2c driver to unmap DMA mappings
during system "reboot" or "shutdown".
Signed-off-by: Roja Rani Yarubandi <rojay@codeaurora.org>
---
drivers/i2c/busses/i2c-qcom-geni.c | 36 ++++++++++++++++++++++++++++++
include/linux/qcom-geni-se.h | 5 +++++
2 files changed, 41 insertions(+)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
index 53ca41f76080..749c225f95c4 100644
--- a/drivers/i2c/busses/i2c-qcom-geni.c
+++ b/drivers/i2c/busses/i2c-qcom-geni.c
@@ -613,6 +613,41 @@ static int geni_i2c_remove(struct platform_device *pdev)
return 0;
}
+static void geni_i2c_shutdown(struct platform_device *pdev)
+{
+ int ret;
+ struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);
+ struct geni_se *se = &gi2c->se;
+ u32 dma;
+ u32 dma_dbg_reg;
+
+ ret = pm_runtime_get_sync(gi2c->se.dev);
+ if (ret < 0) {
+ dev_err(gi2c->se.dev, "Failed to resume device:%d\n", ret);
+ return;
+ }
+
+ dma = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
+ if (dma) {
+ dma_dbg_reg = readl_relaxed(gi2c->se.base + SE_DMA_DEBUG_REG0);
+ if (dma_dbg_reg & DMA_TX_ACTIVE) {
+ geni_i2c_abort_xfer(gi2c);
+ gi2c->cur_wr = 0;
+ if (gi2c->err)
+ geni_i2c_tx_fsm_rst(gi2c);
+ geni_se_tx_dma_unprep(se, gi2c->tx_dma, gi2c->xfer_len);
+ }
+ if (dma_dbg_reg & DMA_RX_ACTIVE) {
+ geni_i2c_abort_xfer(gi2c);
+ gi2c->cur_rd = 0;
+ if (gi2c->err)
+ geni_i2c_rx_fsm_rst(gi2c);
+ geni_se_rx_dma_unprep(se, gi2c->rx_dma, gi2c->xfer_len);
+ }
+ }
+ pm_runtime_put_sync_suspend(gi2c->se.dev);
+}
+
static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev)
{
int ret;
@@ -673,6 +708,7 @@ 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 dd464943f717..acad69be747d 100644
--- a/include/linux/qcom-geni-se.h
+++ b/include/linux/qcom-geni-se.h
@@ -77,6 +77,7 @@ 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)
@@ -207,6 +208,10 @@ struct geni_se {
#define RX_GENI_CANCEL_IRQ BIT(11)
#define RX_GENI_GP_IRQ_EXT GENMASK(13, 12)
+/* DMA DEBUG 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
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation
next prev parent reply other threads:[~2020-08-14 9:57 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-14 9:55 [PATCH 0/2] Implement Shutdown callback for i2c Roja Rani Yarubandi
2020-08-14 9:55 ` [PATCH 1/2] i2c: i2c-qcom-geni: Add tx_dma, rx_dma and xfer_len to geni_i2c_dev struct Roja Rani Yarubandi
2020-08-19 3:39 ` Stephen Boyd
2020-08-20 10:29 ` rojay
2020-08-14 9:55 ` Roja Rani Yarubandi [this message]
2020-08-19 3:43 ` [PATCH 2/2] i2c: i2c-qcom-geni: Add shutdown callback for i2c Stephen Boyd
2020-08-20 10:30 ` rojay
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200814095540.32115-3-rojay@codeaurora.org \
--to=rojay@codeaurora.org \
--cc=agross@kernel.org \
--cc=akashast@codeaurora.org \
--cc=bjorn.andersson@linaro.org \
--cc=dianders@chromium.org \
--cc=dri-devel@lists.freedesktop.org \
--cc=gregkh@linuxfoundation.org \
--cc=linaro-mm-sig@lists.linaro.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-i2c@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=mka@chromium.org \
--cc=msavaliy@qti.qualcomm.com \
--cc=rnayak@codeaurora.org \
--cc=saiprakash.ranjan@codeaurora.org \
--cc=skakit@codeaurora.org \
--cc=sumit.semwal@linaro.org \
--cc=swboyd@chromium.org \
--cc=wsa@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).