[PATCH] ata: sata_rcar: Fix DMA boundary mask

[PATCH] ata: sata_rcar: Fix DMA boundary mask

[Geert Uytterhoeven]

Before commit 9495b7e92f716ab2 ("driver core: platform: Initialize
dma_parms for platform devices"), the R-Car SATA device didn't have DMA
parameters.  Hence the DMA boundary mask supplied by its driver was
silently ignored, as __scsi_init_queue() doesn't check the return value
of dma_set_seg_boundary(), and the default value of 0xffffffff was used.

Now the device has gained DMA parameters, the driver-supplied value is
used, and the following warning is printed on Salvator-XS:

    DMA-API: sata_rcar ee300000.sata: mapping sg segment across boundary [start=0x00000000ffffe000] [end=0x00000000ffffefff] [boundary=0x000000001ffffffe]
    WARNING: CPU: 5 PID: 38 at kernel/dma/debug.c:1233 debug_dma_map_sg+0x298/0x300

(the range of start/end values depend on whether IOMMU support is
 enabled or not)

The issue here is that SATA_RCAR_DMA_BOUNDARY doesn't have bit 0 set, so
any typical end value, which is odd, will trigger the check.

Fix this by increasing the DMA boundary value by 1.

Fixes: 8bfbeed58665dbbf ("sata_rcar: correct 'sata_rcar_sht'")
Fixes: 9495b7e92f716ab2 ("driver core: platform: Initialize dma_parms for platform devices")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
As by default the DMA debug code prints the first error only, this issue
may be hidden on plain v5.7-rc5, where the FCP driver triggers a similar
warning.  Merging commit dd844fb8e50b12e6 ("media: platform: fcp: Set
appropriate DMA parameters") from the media tree fixes the FCP issue,
and exposes the SATA issue.

I added the second fixes tag because that commit is already being
backported to stable kernels, and this patch thus needs backporting,
too.
---
 drivers/ata/sata_rcar.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/ata/sata_rcar.c b/drivers/ata/sata_rcar.c
index 980aacdbcf3b42b9..752db75b611e8f8a 100644
--- a/drivers/ata/sata_rcar.c
+++ b/drivers/ata/sata_rcar.c
@@ -120,7 +120,7 @@
 /* Descriptor table word 0 bit (when DTA32M = 1) */
 #define SATA_RCAR_DTEND			BIT(0)
 
-#define SATA_RCAR_DMA_BOUNDARY		0x1FFFFFFEUL
+#define SATA_RCAR_DMA_BOUNDARY		0x1FFFFFFFUL
 
 /* Gen2 Physical Layer Control Registers */
 #define RCAR_GEN2_PHY_CTL1_REG		0x1704
-- 
2.17.1

Re: [PATCH] ata: sata_rcar: Fix DMA boundary mask

[Christoph Hellwig]

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [PATCH] ata: sata_rcar: Fix DMA boundary mask

[Greg Kroah-Hartman]

On Wed, May 13, 2020 at 01:04:26PM +0200, Geert Uytterhoeven wrote:
> Before commit 9495b7e92f716ab2 ("driver core: platform: Initialize
> dma_parms for platform devices"), the R-Car SATA device didn't have DMA
> parameters.  Hence the DMA boundary mask supplied by its driver was
> silently ignored, as __scsi_init_queue() doesn't check the return value
> of dma_set_seg_boundary(), and the default value of 0xffffffff was used.
> 
> Now the device has gained DMA parameters, the driver-supplied value is
> used, and the following warning is printed on Salvator-XS:
> 
>     DMA-API: sata_rcar ee300000.sata: mapping sg segment across boundary [start=0x00000000ffffe000] [end=0x00000000ffffefff] [boundary=0x000000001ffffffe]
>     WARNING: CPU: 5 PID: 38 at kernel/dma/debug.c:1233 debug_dma_map_sg+0x298/0x300
> 
> (the range of start/end values depend on whether IOMMU support is
>  enabled or not)
> 
> The issue here is that SATA_RCAR_DMA_BOUNDARY doesn't have bit 0 set, so
> any typical end value, which is odd, will trigger the check.
> 
> Fix this by increasing the DMA boundary value by 1.
> 
> Fixes: 8bfbeed58665dbbf ("sata_rcar: correct 'sata_rcar_sht'")
> Fixes: 9495b7e92f716ab2 ("driver core: platform: Initialize dma_parms for platform devices")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Re: [PATCH] ata: sata_rcar: Fix DMA boundary mask

[Sergei Shtylyov]

Hello!

On 13.05.2020 14:04, Geert Uytterhoeven wrote:

> Before commit 9495b7e92f716ab2 ("driver core: platform: Initialize
> dma_parms for platform devices"), the R-Car SATA device didn't have DMA
> parameters.  Hence the DMA boundary mask supplied by its driver was
> silently ignored, as __scsi_init_queue() doesn't check the return value
> of dma_set_seg_boundary(), and the default value of 0xffffffff was used.
> 
> Now the device has gained DMA parameters, the driver-supplied value is
> used, and the following warning is printed on Salvator-XS:
> 
>      DMA-API: sata_rcar ee300000.sata: mapping sg segment across boundary [start=0x00000000ffffe000] [end=0x00000000ffffefff] [boundary=0x000000001ffffffe]
>      WARNING: CPU: 5 PID: 38 at kernel/dma/debug.c:1233 debug_dma_map_sg+0x298/0x300
> 
> (the range of start/end values depend on whether IOMMU support is
>   enabled or not)
> 
> The issue here is that SATA_RCAR_DMA_BOUNDARY doesn't have bit 0 set, so
> any typical end value, which is odd, will trigger the check.
> 
> Fix this by increasing the DMA boundary value by 1.
> 
> Fixes: 8bfbeed58665dbbf ("sata_rcar: correct 'sata_rcar_sht'")
> Fixes: 9495b7e92f716ab2 ("driver core: platform: Initialize dma_parms for platform devices")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Reviewed-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

    Sorry, my mistake that went undetected for many years. :-)

MBR, Sergei

RE: [PATCH] ata: sata_rcar: Fix DMA boundary mask

[Prabhakar Mahadev Lad]

Hi Geert,

Thank you for the patch.

> -----Original Message-----
> From: linux-ide-owner@vger.kernel.org <linux-ide-owner@vger.kernel.org> On Behalf Of Geert Uytterhoeven <geert+renesas@glider.be>
> Sent: 13 May 2020 12:04
> To: Jens Axboe <axboe@kernel.dk>; Ulf Hansson <ulf.hansson@linaro.org>; Greg Kroah-Hartman <gregkh@linuxfoundation.org>;
> Christoph Hellwig <hch@lst.de>
> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>; linux-ide@vger.kernel.org; linux-renesas-soc@vger.kernel.org; linux-
> scsi@vger.kernel.org; linux-kernel@vger.kernel.org; Geert Uytterhoeven <geert+renesas@glider.be>
> Subject: [PATCH] ata: sata_rcar: Fix DMA boundary mask
>
> Before commit 9495b7e92f716ab2 ("driver core: platform: Initialize
> dma_parms for platform devices"), the R-Car SATA device didn't have DMA
> parameters.  Hence the DMA boundary mask supplied by its driver was
> silently ignored, as __scsi_init_queue() doesn't check the return value
> of dma_set_seg_boundary(), and the default value of 0xffffffff was used.
>
> Now the device has gained DMA parameters, the driver-supplied value is
> used, and the following warning is printed on Salvator-XS:
>
>     DMA-API: sata_rcar ee300000.sata: mapping sg segment across boundary [start=0x00000000ffffe000] [end=0x00000000ffffefff]
> [boundary=0x000000001ffffffe]
>     WARNING: CPU: 5 PID: 38 at kernel/dma/debug.c:1233 debug_dma_map_sg+0x298/0x300
>
> (the range of start/end values depend on whether IOMMU support is
>  enabled or not)
>
> The issue here is that SATA_RCAR_DMA_BOUNDARY doesn't have bit 0 set, so
> any typical end value, which is odd, will trigger the check.
>
> Fix this by increasing the DMA boundary value by 1.
>
> Fixes: 8bfbeed58665dbbf ("sata_rcar: correct 'sata_rcar_sht'")
> Fixes: 9495b7e92f716ab2 ("driver core: platform: Initialize dma_parms for platform devices")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> As by default the DMA debug code prints the first error only, this issue
> may be hidden on plain v5.7-rc5, where the FCP driver triggers a similar
> warning.  Merging commit dd844fb8e50b12e6 ("media: platform: fcp: Set
> appropriate DMA parameters") from the media tree fixes the FCP issue,
> and exposes the SATA issue.
>
> I added the second fixes tag because that commit is already being
> backported to stable kernels, and this patch thus needs backporting,
> too.
> ---
>  drivers/ata/sata_rcar.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
Without this patch I see SATA link being reset while doing a dd (dd if=/dev/urandom of=random-data bs=1M count=1000)

Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Cheers,
Prabhakar

> diff --git a/drivers/ata/sata_rcar.c b/drivers/ata/sata_rcar.c
> index 980aacdbcf3b42b9..752db75b611e8f8a 100644
> --- a/drivers/ata/sata_rcar.c
> +++ b/drivers/ata/sata_rcar.c
> @@ -120,7 +120,7 @@
>  /* Descriptor table word 0 bit (when DTA32M = 1) */
>  #define SATA_RCAR_DTENDBIT(0)
>
> -#define SATA_RCAR_DMA_BOUNDARY0x1FFFFFFEUL
> +#define SATA_RCAR_DMA_BOUNDARY0x1FFFFFFFUL
>
>  /* Gen2 Physical Layer Control Registers */
>  #define RCAR_GEN2_PHY_CTL1_REG0x1704
> --
> 2.17.1
>



Renesas Electronics Europe GmbH, Geschaeftsfuehrer/President: Carsten Jauch, Sitz der Gesellschaft/Registered office: Duesseldorf, Arcadiastrasse 10, 40472 Duesseldorf, Germany, Handelsregister/Commercial Register: Duesseldorf, HRB 3708 USt-IDNr./Tax identification no.: DE 119353406 WEEE-Reg.-Nr./WEEE reg. no.: DE 14978647

RE: [PATCH] ata: sata_rcar: Fix DMA boundary mask

[Prabhakar Mahadev Lad]

Hi Geert,

Thank you for the patch.

> -----Original Message-----
> From: linux-ide-owner@vger.kernel.org <linux-ide-owner@vger.kernel.org> On Behalf Of Geert Uytterhoeven <geert+renesas@glider.be>
> Sent: 13 May 2020 12:04
> To: Jens Axboe <axboe@kernel.dk>; Ulf Hansson <ulf.hansson@linaro.org>; Greg Kroah-Hartman <gregkh@linuxfoundation.org>;
> Christoph Hellwig <hch@lst.de>
> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>; linux-ide@vger.kernel.org; linux-renesas-soc@vger.kernel.org; linux-
> scsi@vger.kernel.org; linux-kernel@vger.kernel.org; Geert Uytterhoeven <geert+renesas@glider.be>
> Subject: [PATCH] ata: sata_rcar: Fix DMA boundary mask
>
> Before commit 9495b7e92f716ab2 ("driver core: platform: Initialize
> dma_parms for platform devices"), the R-Car SATA device didn't have DMA
> parameters.  Hence the DMA boundary mask supplied by its driver was
> silently ignored, as __scsi_init_queue() doesn't check the return value
> of dma_set_seg_boundary(), and the default value of 0xffffffff was used.
>
> Now the device has gained DMA parameters, the driver-supplied value is
> used, and the following warning is printed on Salvator-XS:
>
>     DMA-API: sata_rcar ee300000.sata: mapping sg segment across boundary [start=0x00000000ffffe000] [end=0x00000000ffffefff]
> [boundary=0x000000001ffffffe]
>     WARNING: CPU: 5 PID: 38 at kernel/dma/debug.c:1233 debug_dma_map_sg+0x298/0x300
>
> (the range of start/end values depend on whether IOMMU support is
>  enabled or not)
>
> The issue here is that SATA_RCAR_DMA_BOUNDARY doesn't have bit 0 set, so
> any typical end value, which is odd, will trigger the check.
>
> Fix this by increasing the DMA boundary value by 1.
>
> Fixes: 8bfbeed58665dbbf ("sata_rcar: correct 'sata_rcar_sht'")
> Fixes: 9495b7e92f716ab2 ("driver core: platform: Initialize dma_parms for platform devices")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> As by default the DMA debug code prints the first error only, this issue
> may be hidden on plain v5.7-rc5, where the FCP driver triggers a similar
> warning.  Merging commit dd844fb8e50b12e6 ("media: platform: fcp: Set
> appropriate DMA parameters") from the media tree fixes the FCP issue,
> and exposes the SATA issue.
>
> I added the second fixes tag because that commit is already being
> backported to stable kernels, and this patch thus needs backporting,
> too.
> ---
>  drivers/ata/sata_rcar.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
Without this patch I see SATA link being reset while doing a dd (dd if=/dev/urandom of=random-data bs=1M count=1000)

Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Cheers,
Prabhakar

> diff --git a/drivers/ata/sata_rcar.c b/drivers/ata/sata_rcar.c
> index 980aacdbcf3b42b9..752db75b611e8f8a 100644
> --- a/drivers/ata/sata_rcar.c
> +++ b/drivers/ata/sata_rcar.c
> @@ -120,7 +120,7 @@
>  /* Descriptor table word 0 bit (when DTA32M = 1) */
>  #define SATA_RCAR_DTENDBIT(0)
>
> -#define SATA_RCAR_DMA_BOUNDARY0x1FFFFFFEUL
> +#define SATA_RCAR_DMA_BOUNDARY0x1FFFFFFFUL
>
>  /* Gen2 Physical Layer Control Registers */
>  #define RCAR_GEN2_PHY_CTL1_REG0x1704
> --
> 2.17.1
>



Renesas Electronics Europe GmbH, Geschaeftsfuehrer/President: Carsten Jauch, Sitz der Gesellschaft/Registered office: Duesseldorf, Arcadiastrasse 10, 40472 Duesseldorf, Germany, Handelsregister/Commercial Register: Duesseldorf, HRB 3708 USt-IDNr./Tax identification no.: DE 119353406 WEEE-Reg.-Nr./WEEE reg. no.: DE 14978647