[PATCH v3] mmc: dw_mmc: read all data in FIFO after Data transfer over interrupt in pio mode

[PATCH v3] mmc: dw_mmc: read all data in FIFO after Data transfer over interrupt in pio mode

[Kyoungil Kim]

In dwc manual, the below contents are described.
"During end of packet, interrupt is not generated if threshold
programming is larger than any remaining data. It is responsibility
of host to read remaining bytes on seeing Data Transfer Done
interrupt"
We also have seen the data cannot be read fully
when "sg_miter->length" is less than FIFO size.

Signed-off-by: Kyoungil Kim <ki0351.kim@samsung.com>
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
---
 drivers/mmc/host/dw_mmc.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 323c502..41d59da 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -1430,7 +1430,7 @@ static void dw_mci_pull_data(struct dw_mci *host, void *buf, int cnt)
 	host->pull_data(host, buf, cnt);
 }
 
-static void dw_mci_read_data_pio(struct dw_mci *host)
+static void dw_mci_read_data_pio(struct dw_mci *host, bool dto)
 {
 	struct sg_mapping_iter *sg_miter = &host->sg_miter;
 	void *buf;
@@ -1465,7 +1465,9 @@ static void dw_mci_read_data_pio(struct dw_mci *host)
 		sg_miter->consumed = offset;
 		status = mci_readl(host, MINTSTS);
 		mci_writel(host, RINTSTS, SDMMC_INT_RXDR);
-	} while (status & SDMMC_INT_RXDR); /*if the RXDR is ready read again*/
+	/* if the RXDR is ready read again */
+	} while ((status & SDMMC_INT_RXDR) ||
+			(dto && SDMMC_GET_FCNT(mci_readl(host, STATUS))));
 	data->bytes_xfered += nbytes;
 
 	if (!remain) {
@@ -1597,7 +1599,7 @@ static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)
 			smp_wmb();
 			if (host->dir_status == DW_MCI_RECV_STATUS) {
 				if (host->sg != NULL)
-					dw_mci_read_data_pio(host);
+					dw_mci_read_data_pio(host, true);
 			}
 			set_bit(EVENT_DATA_COMPLETE, &host->pending_events);
 			tasklet_schedule(&host->tasklet);
@@ -1606,7 +1608,7 @@ static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)
 		if (pending & SDMMC_INT_RXDR) {
 			mci_writel(host, RINTSTS, SDMMC_INT_RXDR);
 			if (host->dir_status == DW_MCI_RECV_STATUS && host->sg)
-				dw_mci_read_data_pio(host);
+				dw_mci_read_data_pio(host, false);
 		}
 
 		if (pending & SDMMC_INT_TXDR) {
-- 
1.7.4.1

RE: [PATCH v3] mmc: dw_mmc: read all data in FIFO after Data transfer over interrupt in pio mode

[Seungwon Jeon]

Hi Chris,

Could you merge this patch in your tree.
We've verified.

Thanks,
Seungwon Jeon

On Tuesday, January 22, 2013, Kyoungil Kim wrote:
> In dwc manual, the below contents are described.
> "During end of packet, interrupt is not generated if threshold
> programming is larger than any remaining data. It is responsibility
> of host to read remaining bytes on seeing Data Transfer Done
> interrupt"
> We also have seen the data cannot be read fully
> when "sg_miter->length" is less than FIFO size.
> 
> Signed-off-by: Kyoungil Kim <ki0351.kim@samsung.com>
> Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
> Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
> ---
>  drivers/mmc/host/dw_mmc.c |   10 ++++++----
>  1 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> index 323c502..41d59da 100644
> --- a/drivers/mmc/host/dw_mmc.c
> +++ b/drivers/mmc/host/dw_mmc.c
> @@ -1430,7 +1430,7 @@ static void dw_mci_pull_data(struct dw_mci *host, void *buf, int cnt)
>  	host->pull_data(host, buf, cnt);
>  }
> 
> -static void dw_mci_read_data_pio(struct dw_mci *host)
> +static void dw_mci_read_data_pio(struct dw_mci *host, bool dto)
>  {
>  	struct sg_mapping_iter *sg_miter = &host->sg_miter;
>  	void *buf;
> @@ -1465,7 +1465,9 @@ static void dw_mci_read_data_pio(struct dw_mci *host)
>  		sg_miter->consumed = offset;
>  		status = mci_readl(host, MINTSTS);
>  		mci_writel(host, RINTSTS, SDMMC_INT_RXDR);
> -	} while (status & SDMMC_INT_RXDR); /*if the RXDR is ready read again*/
> +	/* if the RXDR is ready read again */
> +	} while ((status & SDMMC_INT_RXDR) ||
> +			(dto && SDMMC_GET_FCNT(mci_readl(host, STATUS))));
>  	data->bytes_xfered += nbytes;
> 
>  	if (!remain) {
> @@ -1597,7 +1599,7 @@ static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)
>  			smp_wmb();
>  			if (host->dir_status == DW_MCI_RECV_STATUS) {
>  				if (host->sg != NULL)
> -					dw_mci_read_data_pio(host);
> +					dw_mci_read_data_pio(host, true);
>  			}
>  			set_bit(EVENT_DATA_COMPLETE, &host->pending_events);
>  			tasklet_schedule(&host->tasklet);
> @@ -1606,7 +1608,7 @@ static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)
>  		if (pending & SDMMC_INT_RXDR) {
>  			mci_writel(host, RINTSTS, SDMMC_INT_RXDR);
>  			if (host->dir_status == DW_MCI_RECV_STATUS && host->sg)
> -				dw_mci_read_data_pio(host);
> +				dw_mci_read_data_pio(host, false);
>  		}
> 
>  		if (pending & SDMMC_INT_TXDR) {
> --
> 1.7.4.1
> 
> --
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Re: [PATCH v3] mmc: dw_mmc: read all data in FIFO after Data transfer over interrupt in pio mode

[Chris Ball]

Hi,

On Mon, Feb 18 2013, Seungwon Jeon wrote:
> Hi Chris,
>
> Could you merge this patch in your tree.
> We've verified.
>
> Thanks,
> Seungwon Jeon
>
> On Tuesday, January 22, 2013, Kyoungil Kim wrote:
>> In dwc manual, the below contents are described.
>> "During end of packet, interrupt is not generated if threshold
>> programming is larger than any remaining data. It is responsibility
>> of host to read remaining bytes on seeing Data Transfer Done
>> interrupt"
>> We also have seen the data cannot be read fully
>> when "sg_miter->length" is less than FIFO size.
>> 
>> Signed-off-by: Kyoungil Kim <ki0351.kim@samsung.com>
>> Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
>> Acked-by: Jaehoon Chung <jh80.chung@samsung.com>

Thanks, pushed to mmc-next for 3.10.

- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child