diff mbox series

mmc: sdhci: disable ADMA when PAGE SIZE is 64K

Message ID 1635302841-18997-1-git-send-email-haibo.chen@nxp.com (mailing list archive)
State New, archived
Headers show
Series mmc: sdhci: disable ADMA when PAGE SIZE is 64K | expand

Commit Message

Bough Chen Oct. 27, 2021, 2:47 a.m. UTC
From: Haibo Chen <haibo.chen@nxp.com>

For ADMA with quirks SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC, it limit
the max segment size as 64K-1. Currently, linux kernel support
4K/16K/64K PAGE_SIZE. If choose 64K PAGE_SIZE, sdhci in ADMA mode
with the upper quirks will meet issue.

Though mmc driver give block layer the max segment size through
blk_queue_max_segment_size(), but in this function, it will compare
the argument with PAGE_SIZE, and will choose PAGE_SIZE if the argument
is smaller than PAGE_SIZE. When PAGE_SIZE is 64K, finally the mmc
request queue will get 64K as the max segment size. Once the sg data
length=64K, ADMA will meet issue. For this case, need to disable ADMA
mode.

Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
---
 drivers/mmc/host/sdhci.c | 6 ++++++
 1 file changed, 6 insertions(+)

Comments

Adrian Hunter Oct. 27, 2021, 5:49 a.m. UTC | #1
On 27/10/2021 05:47, haibo.chen@nxp.com wrote:
> From: Haibo Chen <haibo.chen@nxp.com>
> 
> For ADMA with quirks SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC, it limit
> the max segment size as 64K-1. Currently, linux kernel support
> 4K/16K/64K PAGE_SIZE. If choose 64K PAGE_SIZE, sdhci in ADMA mode
> with the upper quirks will meet issue.
> 
> Though mmc driver give block layer the max segment size through
> blk_queue_max_segment_size(), but in this function, it will compare
> the argument with PAGE_SIZE, and will choose PAGE_SIZE if the argument
> is smaller than PAGE_SIZE. When PAGE_SIZE is 64K, finally the mmc
> request queue will get 64K as the max segment size. Once the sg data
> length=64K, ADMA will meet issue. For this case, need to disable ADMA
> mode.

Sorry, I didn't look closely enough at this.

For the 64K PAGE_SIZE case, did you try blk_queue_virt_boundary()
with a 32K mask instead of blk_queue_max_segment_size() ?
e.g. a hack for testing purposes like this:

diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
index b15c034b42fb..4c3a9d999500 100644
--- a/drivers/mmc/core/queue.c
+++ b/drivers/mmc/core/queue.c
@@ -376,8 +376,7 @@ static void mmc_setup_queue(struct mmc_queue *mq, struct mmc_card *card)
 	 * both blk_queue_max_segment_size().
 	 */
 	if (!host->can_dma_map_merge)
-		blk_queue_max_segment_size(mq->queue,
-			round_down(host->max_seg_size, block_size));
+		blk_queue_virt_boundary(mq->queue, 0x7fff);
 
 	dma_set_max_seg_size(mmc_dev(host), queue_max_segment_size(mq->queue));
 



> 
> Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
> ---
>  drivers/mmc/host/sdhci.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index dbe87995596c..47e0c0156b94 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -4187,6 +4187,12 @@ int sdhci_setup_host(struct sdhci_host *host)
>  		host->flags &= ~SDHCI_USE_ADMA;
>  	}
>  
> +	if ((host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC) &&
> +		PAGE_SIZE >= 65536 && (host->flags & SDHCI_USE_ADMA)) {
> +		DBG("Disabling ADMA as it don't support >= 64K PAGE_SIZE\n");
> +		host->flags &= ~SDHCI_USE_ADMA;
> +	}
> +
>  	if (sdhci_can_64bit_dma(host))
>  		host->flags |= SDHCI_USE_64_BIT_DMA;
>  
>
Bough Chen Oct. 29, 2021, 11:40 a.m. UTC | #2
> -----Original Message-----
> From: Adrian Hunter [mailto:adrian.hunter@intel.com]
> Sent: 2021年10月27日 13:50
> To: Bough Chen <haibo.chen@nxp.com>; ulf.hansson@linaro.org
> Cc: linux-mmc@vger.kernel.org; dl-linux-imx <linux-imx@nxp.com>
> Subject: Re: [PATCH] mmc: sdhci: disable ADMA when PAGE SIZE is 64K
> 
> On 27/10/2021 05:47, haibo.chen@nxp.com wrote:
> > From: Haibo Chen <haibo.chen@nxp.com>
> >
> > For ADMA with quirks SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC, it
> limit
> > the max segment size as 64K-1. Currently, linux kernel support
> > 4K/16K/64K PAGE_SIZE. If choose 64K PAGE_SIZE, sdhci in ADMA mode with
> > the upper quirks will meet issue.
> >
> > Though mmc driver give block layer the max segment size through
> > blk_queue_max_segment_size(), but in this function, it will compare
> > the argument with PAGE_SIZE, and will choose PAGE_SIZE if the argument
> > is smaller than PAGE_SIZE. When PAGE_SIZE is 64K, finally the mmc
> > request queue will get 64K as the max segment size. Once the sg data
> > length=64K, ADMA will meet issue. For this case, need to disable ADMA
> > mode.
> 
> Sorry, I didn't look closely enough at this.
> 
> For the 64K PAGE_SIZE case, did you try blk_queue_virt_boundary() with a 32K
> mask instead of blk_queue_max_segment_size() ?
> e.g. a hack for testing purposes like this:

I test on my board, this do not work, I still can see sg data_length = 65536.

Best Regards
Haibo Chen
> 
> diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c index
> b15c034b42fb..4c3a9d999500 100644
> --- a/drivers/mmc/core/queue.c
> +++ b/drivers/mmc/core/queue.c
> @@ -376,8 +376,7 @@ static void mmc_setup_queue(struct mmc_queue *mq,
> struct mmc_card *card)
>  	 * both blk_queue_max_segment_size().
>  	 */
>  	if (!host->can_dma_map_merge)
> -		blk_queue_max_segment_size(mq->queue,
> -			round_down(host->max_seg_size, block_size));
> +		blk_queue_virt_boundary(mq->queue, 0x7fff);
> 
>  	dma_set_max_seg_size(mmc_dev(host),
> queue_max_segment_size(mq->queue));
> 
> 
> 
> 
> >
> > Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
> > ---
> >  drivers/mmc/host/sdhci.c | 6 ++++++
> >  1 file changed, 6 insertions(+)
> >
> > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index
> > dbe87995596c..47e0c0156b94 100644
> > --- a/drivers/mmc/host/sdhci.c
> > +++ b/drivers/mmc/host/sdhci.c
> > @@ -4187,6 +4187,12 @@ int sdhci_setup_host(struct sdhci_host *host)
> >  		host->flags &= ~SDHCI_USE_ADMA;
> >  	}
> >
> > +	if ((host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC) &&
> > +		PAGE_SIZE >= 65536 && (host->flags & SDHCI_USE_ADMA)) {
> > +		DBG("Disabling ADMA as it don't support >= 64K PAGE_SIZE\n");
> > +		host->flags &= ~SDHCI_USE_ADMA;
> > +	}
> > +
> >  	if (sdhci_can_64bit_dma(host))
> >  		host->flags |= SDHCI_USE_64_BIT_DMA;
> >
> >
Adrian Hunter Nov. 9, 2021, 8:41 a.m. UTC | #3
On 29/10/2021 14:40, Bough Chen wrote:
>> -----Original Message-----
>> From: Adrian Hunter [mailto:adrian.hunter@intel.com]
>> Sent: 2021年10月27日 13:50
>> To: Bough Chen <haibo.chen@nxp.com>; ulf.hansson@linaro.org
>> Cc: linux-mmc@vger.kernel.org; dl-linux-imx <linux-imx@nxp.com>
>> Subject: Re: [PATCH] mmc: sdhci: disable ADMA when PAGE SIZE is 64K
>>
>> On 27/10/2021 05:47, haibo.chen@nxp.com wrote:
>>> From: Haibo Chen <haibo.chen@nxp.com>
>>>
>>> For ADMA with quirks SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC, it
>> limit
>>> the max segment size as 64K-1. Currently, linux kernel support
>>> 4K/16K/64K PAGE_SIZE. If choose 64K PAGE_SIZE, sdhci in ADMA mode with
>>> the upper quirks will meet issue.
>>>
>>> Though mmc driver give block layer the max segment size through
>>> blk_queue_max_segment_size(), but in this function, it will compare
>>> the argument with PAGE_SIZE, and will choose PAGE_SIZE if the argument
>>> is smaller than PAGE_SIZE. When PAGE_SIZE is 64K, finally the mmc
>>> request queue will get 64K as the max segment size. Once the sg data
>>> length=64K, ADMA will meet issue. For this case, need to disable ADMA
>>> mode.
>>
>> Sorry, I didn't look closely enough at this.
>>
>> For the 64K PAGE_SIZE case, did you try blk_queue_virt_boundary() with a 32K
>> mask instead of blk_queue_max_segment_size() ?
>> e.g. a hack for testing purposes like this:
> 
> I test on my board, this do not work, I still can see sg data_length = 65536.

What about tweaking the logic to write ADMA descriptors?
Something like below for instance?



diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 269c86569402..07c6da1f2f0f 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -771,7 +771,19 @@ static void sdhci_adma_table_pre(struct sdhci_host *host,
 			len -= offset;
 		}
 
-		BUG_ON(len > 65536);
+		/*
+		 * The block layer forces a minimum segment size of PAGE_SIZE,
+		 * so 'len' can be too big here if PAGE_SIZE >= 64KiB. Write
+		 * multiple descriptors, noting that the ADMA table is sized
+		 * for 4KiB chunks anyway, so it will be big enough.
+		 */
+		while (len > host->max_adma) {
+			int n = 32 * 1024; /* 32KiB*/
+
+			__sdhci_adma_write_desc(host, &desc, addr, n, ADMA2_TRAN_VALID);
+			addr += n;
+			len -= n;
+		}
 
 		/* tran, valid */
 		if (len)
@@ -3968,6 +3980,7 @@ struct sdhci_host *sdhci_alloc_host(struct device *dev,
 	 * descriptor for each segment, plus 1 for a nop end descriptor.
 	 */
 	host->adma_table_cnt = SDHCI_MAX_SEGS * 2 + 1;
+	host->max_adma = 65536;
 
 	host->max_timeout_count = 0xE;
 
@@ -4633,10 +4646,12 @@ int sdhci_setup_host(struct sdhci_host *host)
 	 * be larger than 64 KiB though.
 	 */
 	if (host->flags & SDHCI_USE_ADMA) {
-		if (host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC)
+		if (host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC) {
+			host->max_adma = 65532; /* 32-bit alignment */
 			mmc->max_seg_size = 65535;
-		else
+		} else {
 			mmc->max_seg_size = 65536;
+		}
 	} else {
 		mmc->max_seg_size = mmc->max_req_size;
 	}
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index bb883553d3b4..d7929d725730 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -340,7 +340,8 @@ struct sdhci_adma2_64_desc {
 
 /*
  * Maximum segments assuming a 512KiB maximum requisition size and a minimum
- * 4KiB page size.
+ * 4KiB page size. Note this also allows enough for multiple descriptors in
+ * case of PAGE_SIZE >= 64KiB.
  */
 #define SDHCI_MAX_SEGS		128
 
@@ -543,6 +544,7 @@ struct sdhci_host {
 	unsigned int blocks;	/* remaining PIO blocks */
 
 	int sg_count;		/* Mapped sg entries */
+	int max_adma;		/* Max. length in ADMA descriptor */
 
 	void *adma_table;	/* ADMA descriptor table */
 	void *align_buffer;	/* Bounce buffer */
Bough Chen Nov. 12, 2021, 2:02 a.m. UTC | #4
> -----Original Message-----
> From: Adrian Hunter [mailto:adrian.hunter@intel.com]
> Sent: 2021年11月9日 16:42
> To: Bough Chen <haibo.chen@nxp.com>; ulf.hansson@linaro.org
> Cc: linux-mmc@vger.kernel.org; dl-linux-imx <linux-imx@nxp.com>
> Subject: Re: [PATCH] mmc: sdhci: disable ADMA when PAGE SIZE is 64K
> 
> On 29/10/2021 14:40, Bough Chen wrote:
> >> -----Original Message-----
> >> From: Adrian Hunter [mailto:adrian.hunter@intel.com]
> >> Sent: 2021年10月27日 13:50
> >> To: Bough Chen <haibo.chen@nxp.com>; ulf.hansson@linaro.org
> >> Cc: linux-mmc@vger.kernel.org; dl-linux-imx <linux-imx@nxp.com>
> >> Subject: Re: [PATCH] mmc: sdhci: disable ADMA when PAGE SIZE is 64K
> >>
> >> On 27/10/2021 05:47, haibo.chen@nxp.com wrote:
> >>> From: Haibo Chen <haibo.chen@nxp.com>
> >>>
> >>> For ADMA with quirks SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC, it
> >> limit
> >>> the max segment size as 64K-1. Currently, linux kernel support
> >>> 4K/16K/64K PAGE_SIZE. If choose 64K PAGE_SIZE, sdhci in ADMA mode
> >>> with the upper quirks will meet issue.
> >>>
> >>> Though mmc driver give block layer the max segment size through
> >>> blk_queue_max_segment_size(), but in this function, it will compare
> >>> the argument with PAGE_SIZE, and will choose PAGE_SIZE if the
> >>> argument is smaller than PAGE_SIZE. When PAGE_SIZE is 64K, finally
> >>> the mmc request queue will get 64K as the max segment size. Once the
> >>> sg data length=64K, ADMA will meet issue. For this case, need to
> >>> disable ADMA mode.
> >>
> >> Sorry, I didn't look closely enough at this.
> >>
> >> For the 64K PAGE_SIZE case, did you try blk_queue_virt_boundary()
> >> with a 32K mask instead of blk_queue_max_segment_size() ?
> >> e.g. a hack for testing purposes like this:
> >
> > I test on my board, this do not work, I still can see sg data_length = 65536.
> 
> What about tweaking the logic to write ADMA descriptors?
> Something like below for instance?

Hi Adrian,

I prefer this solution.
I test this on my board, it works fine.
I think you can send this patch out with my Tested-by.

Best Regards
Haibo Chen
> 
> 
> 
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index
> 269c86569402..07c6da1f2f0f 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -771,7 +771,19 @@ static void sdhci_adma_table_pre(struct sdhci_host
> *host,
>  			len -= offset;
>  		}
> 
> -		BUG_ON(len > 65536);
> +		/*
> +		 * The block layer forces a minimum segment size of PAGE_SIZE,
> +		 * so 'len' can be too big here if PAGE_SIZE >= 64KiB. Write
> +		 * multiple descriptors, noting that the ADMA table is sized
> +		 * for 4KiB chunks anyway, so it will be big enough.
> +		 */
> +		while (len > host->max_adma) {
> +			int n = 32 * 1024; /* 32KiB*/
> +
> +			__sdhci_adma_write_desc(host, &desc, addr, n,
> ADMA2_TRAN_VALID);
> +			addr += n;
> +			len -= n;
> +		}
> 
>  		/* tran, valid */
>  		if (len)
> @@ -3968,6 +3980,7 @@ struct sdhci_host *sdhci_alloc_host(struct device
> *dev,
>  	 * descriptor for each segment, plus 1 for a nop end descriptor.
>  	 */
>  	host->adma_table_cnt = SDHCI_MAX_SEGS * 2 + 1;
> +	host->max_adma = 65536;
> 
>  	host->max_timeout_count = 0xE;
> 
> @@ -4633,10 +4646,12 @@ int sdhci_setup_host(struct sdhci_host *host)
>  	 * be larger than 64 KiB though.
>  	 */
>  	if (host->flags & SDHCI_USE_ADMA) {
> -		if (host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC)
> +		if (host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC) {
> +			host->max_adma = 65532; /* 32-bit alignment */
>  			mmc->max_seg_size = 65535;
> -		else
> +		} else {
>  			mmc->max_seg_size = 65536;
> +		}
>  	} else {
>  		mmc->max_seg_size = mmc->max_req_size;
>  	}
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index
> bb883553d3b4..d7929d725730 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -340,7 +340,8 @@ struct sdhci_adma2_64_desc {
> 
>  /*
>   * Maximum segments assuming a 512KiB maximum requisition size and a
> minimum
> - * 4KiB page size.
> + * 4KiB page size. Note this also allows enough for multiple
> + descriptors in
> + * case of PAGE_SIZE >= 64KiB.
>   */
>  #define SDHCI_MAX_SEGS		128
> 
> @@ -543,6 +544,7 @@ struct sdhci_host {
>  	unsigned int blocks;	/* remaining PIO blocks */
> 
>  	int sg_count;		/* Mapped sg entries */
> +	int max_adma;		/* Max. length in ADMA descriptor */
> 
>  	void *adma_table;	/* ADMA descriptor table */
>  	void *align_buffer;	/* Bounce buffer */
> --
> 2.25.1
> 
> 
> 
> 
> >
> > Best Regards
> > Haibo Chen
> >>
> >> diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c index
> >> b15c034b42fb..4c3a9d999500 100644
> >> --- a/drivers/mmc/core/queue.c
> >> +++ b/drivers/mmc/core/queue.c
> >> @@ -376,8 +376,7 @@ static void mmc_setup_queue(struct mmc_queue
> *mq,
> >> struct mmc_card *card)
> >>  	 * both blk_queue_max_segment_size().
> >>  	 */
> >>  	if (!host->can_dma_map_merge)
> >> -		blk_queue_max_segment_size(mq->queue,
> >> -			round_down(host->max_seg_size, block_size));
> >> +		blk_queue_virt_boundary(mq->queue, 0x7fff);
> >>
> >>  	dma_set_max_seg_size(mmc_dev(host),
> >> queue_max_segment_size(mq->queue));
> >>
> >>
> >>
> >>
> >>>
> >>> Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
> >>> ---
> >>>  drivers/mmc/host/sdhci.c | 6 ++++++
> >>>  1 file changed, 6 insertions(+)
> >>>
> >>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index
> >>> dbe87995596c..47e0c0156b94 100644
> >>> --- a/drivers/mmc/host/sdhci.c
> >>> +++ b/drivers/mmc/host/sdhci.c
> >>> @@ -4187,6 +4187,12 @@ int sdhci_setup_host(struct sdhci_host *host)
> >>>  		host->flags &= ~SDHCI_USE_ADMA;
> >>>  	}
> >>>
> >>> +	if ((host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC)
> &&
> >>> +		PAGE_SIZE >= 65536 && (host->flags & SDHCI_USE_ADMA)) {
> >>> +		DBG("Disabling ADMA as it don't support >= 64K
> PAGE_SIZE\n");
> >>> +		host->flags &= ~SDHCI_USE_ADMA;
> >>> +	}
> >>> +
> >>>  	if (sdhci_can_64bit_dma(host))
> >>>  		host->flags |= SDHCI_USE_64_BIT_DMA;
> >>>
> >>>
> >
diff mbox series

Patch

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index dbe87995596c..47e0c0156b94 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -4187,6 +4187,12 @@  int sdhci_setup_host(struct sdhci_host *host)
 		host->flags &= ~SDHCI_USE_ADMA;
 	}
 
+	if ((host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC) &&
+		PAGE_SIZE >= 65536 && (host->flags & SDHCI_USE_ADMA)) {
+		DBG("Disabling ADMA as it don't support >= 64K PAGE_SIZE\n");
+		host->flags &= ~SDHCI_USE_ADMA;
+	}
+
 	if (sdhci_can_64bit_dma(host))
 		host->flags |= SDHCI_USE_64_BIT_DMA;