[RFC PATCH 0/6] tmio/sdhi: add cmd23 support

[RFC PATCH 0/6] tmio/sdhi: add cmd23 support

[Wolfram Sang]

This series adds CMD23 support to SDHI. It was tested on H2 (Gen2, Lager) and
M3W (Gen3, Salvator-X). The test procedure can be found here:

http://elinux.org/Tests:SDHI-CMD23

Patches are based on mmc/next from today. A branch can be found here:

git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git renesas/topic/sdhi-cmd23

The reason these patches are RFC is that they should not be applied right now.
We also have some heavier refactoring going on and it is likely to be better to
apply these patches after the refactoring. However, I send them out now to
encourage review and testing. They do work as expected in my tests.

Thanks and kind regards,

   Wolfram


Wolfram Sang (6):
  mmc: tmio: make tmio_mmc_request function more readable
  mmc: tmio: refactor handling mrq
  mmc: tmio: remove outdated comment
  mmc: tmio: move finish_request function further down
  mmc: tmio: add CMD23 support
  mmc: sdhi: add CMD23 support to R-Car Gen2 & Gen3

 drivers/mmc/host/sh_mobile_sdhi.c |   4 +-
 drivers/mmc/host/tmio_mmc_pio.c   | 135 ++++++++++++++++++++++----------------
 2 files changed, 80 insertions(+), 59 deletions(-)

-- 
2.11.0

[RFC PATCH 1/6] mmc: tmio: make tmio_mmc_request function more readable

[Wolfram Sang]

This part confused me and I had to read it twice until I got it. Let's
follow the standard pattern to bail out if something is wrong and keep
in the body of the function when everything is as expected.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 drivers/mmc/host/tmio_mmc_pio.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c
index a2d92f10501bdd..ba1a233f97f03c 100644
--- a/drivers/mmc/host/tmio_mmc_pio.c
+++ b/drivers/mmc/host/tmio_mmc_pio.c
@@ -889,11 +889,12 @@ static void tmio_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
 	}
 
 	ret = tmio_mmc_start_command(host, mrq->cmd);
-	if (!ret) {
-		schedule_delayed_work(&host->delayed_reset_work,
-				      msecs_to_jiffies(CMDREQ_TIMEOUT));
-		return;
-	}
+	if (ret)
+		goto fail;
+
+	schedule_delayed_work(&host->delayed_reset_work,
+			      msecs_to_jiffies(CMDREQ_TIMEOUT));
+	return;
 
 fail:
 	host->force_pio = false;
-- 
2.11.0

[RFC PATCH 2/6] mmc: tmio: refactor handling mrq

[Wolfram Sang]

Split handling mrq into a seperate function. We need to call it from
another place soon.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 drivers/mmc/host/tmio_mmc_pio.c | 46 +++++++++++++++++++++++------------------
 1 file changed, 26 insertions(+), 20 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c
index ba1a233f97f03c..9d86e3ac626444 100644
--- a/drivers/mmc/host/tmio_mmc_pio.c
+++ b/drivers/mmc/host/tmio_mmc_pio.c
@@ -857,12 +857,36 @@ static int tmio_mmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
 	return ret;
 }
 
+static void tmio_process_mrq(struct tmio_mmc_host *host, struct mmc_request *mrq)
+{
+	int ret;
+
+	if (mrq->data) {
+		ret = tmio_mmc_start_data(host, mrq->data);
+		if (ret)
+			goto fail;
+	}
+
+	ret = tmio_mmc_start_command(host, mrq->cmd);
+	if (ret)
+		goto fail;
+
+	schedule_delayed_work(&host->delayed_reset_work,
+			      msecs_to_jiffies(CMDREQ_TIMEOUT));
+	return;
+
+fail:
+	host->force_pio = false;
+	host->mrq = NULL;
+	mrq->cmd->error = ret;
+	mmc_request_done(host->mmc, mrq);
+}
+
 /* Process requests from the MMC layer */
 static void tmio_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
 {
 	struct tmio_mmc_host *host = mmc_priv(mmc);
 	unsigned long flags;
-	int ret;
 
 	spin_lock_irqsave(&host->lock, flags);
 
@@ -882,25 +906,7 @@ static void tmio_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
 
 	spin_unlock_irqrestore(&host->lock, flags);
 
-	if (mrq->data) {
-		ret = tmio_mmc_start_data(host, mrq->data);
-		if (ret)
-			goto fail;
-	}
-
-	ret = tmio_mmc_start_command(host, mrq->cmd);
-	if (ret)
-		goto fail;
-
-	schedule_delayed_work(&host->delayed_reset_work,
-			      msecs_to_jiffies(CMDREQ_TIMEOUT));
-	return;
-
-fail:
-	host->force_pio = false;
-	host->mrq = NULL;
-	mrq->cmd->error = ret;
-	mmc_request_done(mmc, mrq);
+	tmio_process_mrq(host, mrq);
 }
 
 static int tmio_mmc_clk_enable(struct tmio_mmc_host *host)
-- 
2.11.0

[RFC PATCH 3/6] mmc: tmio: remove outdated comment

[Wolfram Sang]

The obviously wrong comment was added in 2011 with commit df3ef2d3c92c0a
("mmc: protect the tmio_mmc driver against a theoretical race") but
already obsoleted half a year later with commit b9269fdd4f61aa ("mmc:
tmio: fix recursive spinlock, don't schedule with interrupts disabled").

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 drivers/mmc/host/tmio_mmc_pio.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c
index 9d86e3ac626444..36539950347fbc 100644
--- a/drivers/mmc/host/tmio_mmc_pio.c
+++ b/drivers/mmc/host/tmio_mmc_pio.c
@@ -279,7 +279,6 @@ static void tmio_mmc_reset_work(struct work_struct *work)
 	mmc_request_done(host->mmc, mrq);
 }
 
-/* called with host->lock held, interrupts disabled */
 static void tmio_mmc_finish_request(struct tmio_mmc_host *host)
 {
 	struct mmc_request *mrq;
-- 
2.11.0

[RFC PATCH 4/6] mmc: tmio: move finish_request function further down

[Wolfram Sang]

Plain code move with no changes. Needed for refactoring. Also, looks
nicer if request and finish_request are next to each other.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 drivers/mmc/host/tmio_mmc_pio.c | 76 ++++++++++++++++++++---------------------
 1 file changed, 38 insertions(+), 38 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c
index 36539950347fbc..b3ecb2e2e344c3 100644
--- a/drivers/mmc/host/tmio_mmc_pio.c
+++ b/drivers/mmc/host/tmio_mmc_pio.c
@@ -279,44 +279,6 @@ static void tmio_mmc_reset_work(struct work_struct *work)
 	mmc_request_done(host->mmc, mrq);
 }
 
-static void tmio_mmc_finish_request(struct tmio_mmc_host *host)
-{
-	struct mmc_request *mrq;
-	unsigned long flags;
-
-	spin_lock_irqsave(&host->lock, flags);
-
-	mrq = host->mrq;
-	if (IS_ERR_OR_NULL(mrq)) {
-		spin_unlock_irqrestore(&host->lock, flags);
-		return;
-	}
-
-	host->cmd = NULL;
-	host->data = NULL;
-	host->force_pio = false;
-
-	cancel_delayed_work(&host->delayed_reset_work);
-
-	host->mrq = NULL;
-	spin_unlock_irqrestore(&host->lock, flags);
-
-	if (mrq->cmd->error || (mrq->data && mrq->data->error))
-		tmio_mmc_abort_dma(host);
-
-	if (host->check_scc_error)
-		host->check_scc_error(host);
-
-	mmc_request_done(host->mmc, mrq);
-}
-
-static void tmio_mmc_done_work(struct work_struct *work)
-{
-	struct tmio_mmc_host *host = container_of(work, struct tmio_mmc_host,
-						  done);
-	tmio_mmc_finish_request(host);
-}
-
 /* These are the bitmasks the tmio chip requires to implement the MMC response
  * types. Note that R1 and R6 are the same in this scheme. */
 #define APP_CMD        0x0040
@@ -908,6 +870,44 @@ static void tmio_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
 	tmio_process_mrq(host, mrq);
 }
 
+static void tmio_mmc_finish_request(struct tmio_mmc_host *host)
+{
+	struct mmc_request *mrq;
+	unsigned long flags;
+
+	spin_lock_irqsave(&host->lock, flags);
+
+	mrq = host->mrq;
+	if (IS_ERR_OR_NULL(mrq)) {
+		spin_unlock_irqrestore(&host->lock, flags);
+		return;
+	}
+
+	host->cmd = NULL;
+	host->data = NULL;
+	host->force_pio = false;
+
+	cancel_delayed_work(&host->delayed_reset_work);
+
+	host->mrq = NULL;
+	spin_unlock_irqrestore(&host->lock, flags);
+
+	if (mrq->cmd->error || (mrq->data && mrq->data->error))
+		tmio_mmc_abort_dma(host);
+
+	if (host->check_scc_error)
+		host->check_scc_error(host);
+
+	mmc_request_done(host->mmc, mrq);
+}
+
+static void tmio_mmc_done_work(struct work_struct *work)
+{
+	struct tmio_mmc_host *host = container_of(work, struct tmio_mmc_host,
+						  done);
+	tmio_mmc_finish_request(host);
+}
+
 static int tmio_mmc_clk_enable(struct tmio_mmc_host *host)
 {
 	if (!host->clk_enable)
-- 
2.11.0

[RFC PATCH 5/6] mmc: tmio: add CMD23 support

[Wolfram Sang]

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 drivers/mmc/host/tmio_mmc_pio.c | 41 ++++++++++++++++++++++++++++-------------
 1 file changed, 28 insertions(+), 13 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c
index b3ecb2e2e344c3..a81b86ca735845 100644
--- a/drivers/mmc/host/tmio_mmc_pio.c
+++ b/drivers/mmc/host/tmio_mmc_pio.c
@@ -332,11 +332,11 @@ static int tmio_mmc_start_command(struct tmio_mmc_host *host, struct mmc_command
 			c |= TRANSFER_MULTI;
 
 			/*
-			 * Disable auto CMD12 at IO_RW_EXTENDED when
-			 * multiple block transfer
+			 * Disable auto CMD12 at IO_RW_EXTENDED and SET_BLOCK_COUNT
+			 * when doing multiple block transfer
 			 */
 			if ((host->pdata->flags & TMIO_MMC_HAVE_CMD12_CTRL) &&
-			    (cmd->opcode == SD_IO_RW_EXTENDED))
+			    (cmd->opcode == SD_IO_RW_EXTENDED || host->mrq->sbc))
 				c |= NO_CMD12_ISSUE;
 		}
 		if (data->flags & MMC_DATA_READ)
@@ -513,7 +513,7 @@ void tmio_mmc_do_data_irq(struct tmio_mmc_host *host)
 			host->mrq);
 	}
 
-	if (stop) {
+	if (stop && !host->mrq->sbc) {
 		if (stop->opcode != MMC_STOP_TRANSMISSION || stop->arg)
 			dev_err(&host->pdev->dev, "unsupported stop: CMD%u,0x%x. We did CMD12,0\n",
 				stop->opcode, stop->arg);
@@ -820,15 +820,21 @@ static int tmio_mmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
 
 static void tmio_process_mrq(struct tmio_mmc_host *host, struct mmc_request *mrq)
 {
+	struct mmc_command *cmd;
 	int ret;
 
-	if (mrq->data) {
-		ret = tmio_mmc_start_data(host, mrq->data);
-		if (ret)
-			goto fail;
+	if (mrq->sbc && host->cmd != mrq->sbc) {
+		cmd = mrq->sbc;
+	} else {
+		cmd = mrq->cmd;
+		if (mrq->data) {
+			ret = tmio_mmc_start_data(host, mrq->data);
+			if (ret)
+				goto fail;
+		}
 	}
 
-	ret = tmio_mmc_start_command(host, mrq->cmd);
+	ret = tmio_mmc_start_command(host, cmd);
 	if (ret)
 		goto fail;
 
@@ -883,13 +889,16 @@ static void tmio_mmc_finish_request(struct tmio_mmc_host *host)
 		return;
 	}
 
-	host->cmd = NULL;
-	host->data = NULL;
-	host->force_pio = false;
+	/* If not SET_BLOCK_COUNT, clear old data */
+	if (host->cmd != mrq->sbc) {
+		host->cmd = NULL;
+		host->data = NULL;
+		host->force_pio = false;
+		host->mrq = NULL;
+	}
 
 	cancel_delayed_work(&host->delayed_reset_work);
 
-	host->mrq = NULL;
 	spin_unlock_irqrestore(&host->lock, flags);
 
 	if (mrq->cmd->error || (mrq->data && mrq->data->error))
@@ -898,6 +907,12 @@ static void tmio_mmc_finish_request(struct tmio_mmc_host *host)
 	if (host->check_scc_error)
 		host->check_scc_error(host);
 
+	/* If SET_BLOCK_COUNT, continue with main command */
+	if (host->mrq) {
+		tmio_process_mrq(host, mrq);
+		return;
+	}
+
 	mmc_request_done(host->mmc, mrq);
 }
 
-- 
2.11.0

[RFC PATCH 6/6] mmc: sdhi: add CMD23 support to R-Car Gen2 & Gen3

[Wolfram Sang]

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 drivers/mmc/host/sh_mobile_sdhi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/sh_mobile_sdhi.c b/drivers/mmc/host/sh_mobile_sdhi.c
index bc6be0dbea3927..4843ce800c918d 100644
--- a/drivers/mmc/host/sh_mobile_sdhi.c
+++ b/drivers/mmc/host/sh_mobile_sdhi.c
@@ -96,7 +96,7 @@ static struct sh_mobile_sdhi_scc rcar_gen2_scc_taps[] = {
 static const struct sh_mobile_sdhi_of_data of_rcar_gen2_compatible = {
 	.tmio_flags	= TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_WRPROTECT_DISABLE |
 			  TMIO_MMC_CLK_ACTUAL | TMIO_MMC_MIN_RCAR2,
-	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ,
+	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ | MMC_CAP_CMD23,
 	.dma_buswidth	= DMA_SLAVE_BUSWIDTH_4_BYTES,
 	.dma_rx_offset	= 0x2000,
 	.scc_offset	= 0x0300,
@@ -115,7 +115,7 @@ static struct sh_mobile_sdhi_scc rcar_gen3_scc_taps[] = {
 static const struct sh_mobile_sdhi_of_data of_rcar_gen3_compatible = {
 	.tmio_flags	= TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_WRPROTECT_DISABLE |
 			  TMIO_MMC_CLK_ACTUAL | TMIO_MMC_MIN_RCAR2,
-	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ,
+	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ | MMC_CAP_CMD23,
 	.bus_shift	= 2,
 	.scc_offset	= 0x1000,
 	.taps		= rcar_gen3_scc_taps,
-- 
2.11.0

Re: [RFC PATCH 1/6] mmc: tmio: make tmio_mmc_request function more readable

[Geert Uytterhoeven]

On Mon, May 1, 2017 at 11:03 AM, Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> This part confused me and I had to read it twice until I got it. Let's
> follow the standard pattern to bail out if something is wrong and keep
> in the body of the function when everything is as expected.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [RFC PATCH 2/6] mmc: tmio: refactor handling mrq

[Geert Uytterhoeven]

On Mon, May 1, 2017 at 11:03 AM, Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> Split handling mrq into a seperate function. We need to call it from
> another place soon.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [RFC PATCH 3/6] mmc: tmio: remove outdated comment

[Geert Uytterhoeven]

On Mon, May 1, 2017 at 11:03 AM, Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> The obviously wrong comment was added in 2011 with commit df3ef2d3c92c0a
> ("mmc: protect the tmio_mmc driver against a theoretical race") but
> already obsoleted half a year later with commit b9269fdd4f61aa ("mmc:
> tmio: fix recursive spinlock, don't schedule with interrupts disabled").

Fixes: b9269fdd4f61aa ("mmc: tmio: fix recursive spinlock, don't
schedule with interrupts disabled")

> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [RFC PATCH 4/6] mmc: tmio: move finish_request function further down

[Geert Uytterhoeven]

On Mon, May 1, 2017 at 11:03 AM, Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> Plain code move with no changes. Needed for refactoring. Also, looks
> nicer if request and finish_request are next to each other.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [RFC PATCH 6/6] mmc: sdhi: add CMD23 support to R-Car Gen2 & Gen3

[Simon Horman]

On Mon, May 01, 2017 at 11:03:46AM +0200, Wolfram Sang wrote:
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
>  drivers/mmc/host/sh_mobile_sdhi.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mmc/host/sh_mobile_sdhi.c b/drivers/mmc/host/sh_mobile_sdhi.c
> index bc6be0dbea3927..4843ce800c918d 100644
> --- a/drivers/mmc/host/sh_mobile_sdhi.c
> +++ b/drivers/mmc/host/sh_mobile_sdhi.c
> @@ -96,7 +96,7 @@ static struct sh_mobile_sdhi_scc rcar_gen2_scc_taps[] = {
>  static const struct sh_mobile_sdhi_of_data of_rcar_gen2_compatible = {
>  	.tmio_flags	= TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_WRPROTECT_DISABLE |
>  			  TMIO_MMC_CLK_ACTUAL | TMIO_MMC_MIN_RCAR2,
> -	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ,
> +	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ | MMC_CAP_CMD23,

Breaking capabilities over two lines would seem consistent with the
formatting of the rest of the structure.

>  	.dma_buswidth	= DMA_SLAVE_BUSWIDTH_4_BYTES,
>  	.dma_rx_offset	= 0x2000,
>  	.scc_offset	= 0x0300,
> @@ -115,7 +115,7 @@ static struct sh_mobile_sdhi_scc rcar_gen3_scc_taps[] = {
>  static const struct sh_mobile_sdhi_of_data of_rcar_gen3_compatible = {
>  	.tmio_flags	= TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_WRPROTECT_DISABLE |
>  			  TMIO_MMC_CLK_ACTUAL | TMIO_MMC_MIN_RCAR2,
> -	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ,
> +	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ | MMC_CAP_CMD23,
>  	.bus_shift	= 2,
>  	.scc_offset	= 0x1000,
>  	.taps		= rcar_gen3_scc_taps,
> -- 
> 2.11.0
>