From: Bjorn Andersson <bjorn.andersson@linaro.org>
To: Wolfram Sang <wsa@kernel.org>
Cc: Douglas Anderson <dianders@chromium.org>,
Akash Asthana <akashast@codeaurora.org>,
linux-i2c@vger.kernel.org,
Roja Rani Yarubandi <rojay@codeaurora.org>,
Stephen Boyd <swboyd@chromium.org>,
Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
linux-arm-msm@vger.kernel.org, Andy Gross <agross@kernel.org>,
Mukesh Savaliya <msavaliy@codeaurora.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 2/3] Revert "i2c: i2c-qcom-geni: Fix DMA transfer race"
Date: Mon, 26 Oct 2020 10:05:00 -0500 [thread overview]
Message-ID: <20201026150500.GA26921@builder.lan> (raw)
In-Reply-To: <20201013142448.v2.2.I7b22281453b8a18ab16ef2bfd4c641fb1cc6a92c@changeid>
On Tue 13 Oct 16:25 CDT 2020, Douglas Anderson wrote:
> This reverts commit 02b9aec59243c6240fc42884acc958602146ddf6.
>
> As talked about in the patch ("soc: qcom: geni: More properly switch
> to DMA mode"), swapping the order of geni_se_setup_m_cmd() and
> geni_se_xx_dma_prep() can sometimes cause corrupted transfers. Thus
> we traded one problem for another. Now that we've debugged the
> problem further and fixed the geni helper functions to more disable
> FIFO interrupts when we move to DMA mode we can revert it and end up
> with (hopefully) zero problems!
>
> To be explicit, the patch ("soc: qcom: geni: More properly switch
> to DMA mode") is a prerequisite for this one.
>
> Fixes: 02b9aec59243 ("i2c: i2c-qcom-geni: Fix DMA transfer race")
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> Reviewed-by: Stephen Boyd <swboyd@chromium.org>
> Reviewed-by: Akash Asthana <akashast@codeaurora.org>
> Tested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Wolfram, would you like to pick this patch or would you prefer that it
goes together with the other two through the soc tree?
Per Doug's description it has a functional dependency on patch 1, but as
long as all three patches makes it into v5.11 I'm okay with either way.
Regards,
Bjorn
> ---
>
> (no changes since v1)
>
> drivers/i2c/busses/i2c-qcom-geni.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
> index dead5db3315a..32b2a9921b14 100644
> --- a/drivers/i2c/busses/i2c-qcom-geni.c
> +++ b/drivers/i2c/busses/i2c-qcom-geni.c
> @@ -367,6 +367,7 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
> geni_se_select_mode(se, GENI_SE_FIFO);
>
> writel_relaxed(len, se->base + SE_I2C_RX_TRANS_LEN);
> + geni_se_setup_m_cmd(se, I2C_READ, m_param);
>
> if (dma_buf && geni_se_rx_dma_prep(se, dma_buf, len, &rx_dma)) {
> geni_se_select_mode(se, GENI_SE_FIFO);
> @@ -374,8 +375,6 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
> dma_buf = NULL;
> }
>
> - geni_se_setup_m_cmd(se, I2C_READ, m_param);
> -
> time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
> if (!time_left)
> geni_i2c_abort_xfer(gi2c);
> @@ -409,6 +408,7 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
> geni_se_select_mode(se, GENI_SE_FIFO);
>
> writel_relaxed(len, se->base + SE_I2C_TX_TRANS_LEN);
> + geni_se_setup_m_cmd(se, I2C_WRITE, m_param);
>
> if (dma_buf && geni_se_tx_dma_prep(se, dma_buf, len, &tx_dma)) {
> geni_se_select_mode(se, GENI_SE_FIFO);
> @@ -416,8 +416,6 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
> dma_buf = NULL;
> }
>
> - geni_se_setup_m_cmd(se, I2C_WRITE, m_param);
> -
> if (!dma_buf) /* Get FIFO IRQ */
> writel_relaxed(1, se->base + SE_GENI_TX_WATERMARK_REG);
>
> --
> 2.28.0.1011.ga647a8990f-goog
>
next prev parent reply other threads:[~2020-10-26 15:05 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-13 21:25 [PATCH v2 0/3] i2c: i2c-qcom-geni: More properly fix the DMA race Douglas Anderson
2020-10-13 21:25 ` [PATCH v2 1/3] soc: qcom: geni: More properly switch to DMA mode Douglas Anderson
2020-10-13 21:25 ` [PATCH v2 2/3] Revert "i2c: i2c-qcom-geni: Fix DMA transfer race" Douglas Anderson
2020-10-26 15:05 ` Bjorn Andersson [this message]
2020-10-26 15:13 ` Wolfram Sang
2020-10-26 21:15 ` Bjorn Andersson
2020-11-03 20:35 ` Wolfram Sang
2020-10-13 21:25 ` [PATCH v2 3/3] soc: qcom: geni: Optimize/comment select fifo/dma mode Douglas Anderson
2020-10-14 9:17 ` Akash Asthana
2020-10-14 23:51 ` Stephen Boyd
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=20201026150500.GA26921@builder.lan \
--to=bjorn.andersson@linaro.org \
--cc=agross@kernel.org \
--cc=akashast@codeaurora.org \
--cc=dianders@chromium.org \
--cc=dmitry.baryshkov@linaro.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-i2c@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=msavaliy@codeaurora.org \
--cc=rojay@codeaurora.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).