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| Started by | Felipe Balbi <felipe.balbi@linux.intel.com> |
|---|---|
| First post | 2016-03-30 15:20 +0200 |
| Last post | 2016-03-31 10:10 +0200 |
| Articles | 3 — 2 participants |
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Re: [PATCH v3 1/2] usb:dwc3: Enable support for 64-bit system Felipe Balbi <felipe.balbi@linux.intel.com> - 2016-03-30 15:20 +0200
Re: [PATCH v3 1/2] usb:dwc3: Enable support for 64-bit system "Thang Q. Nguyen" <tqnguyen@apm.com> - 2016-03-31 09:40 +0200
Re: [PATCH v3 1/2] usb:dwc3: Enable support for 64-bit system Felipe Balbi <felipe.balbi@linux.intel.com> - 2016-03-31 10:10 +0200
| From | Felipe Balbi <felipe.balbi@linux.intel.com> |
|---|---|
| Date | 2016-03-30 15:20 +0200 |
| Subject | Re: [PATCH v3 1/2] usb:dwc3: Enable support for 64-bit system |
| Message-ID | <riocq-5Wf-11@gated-at.bofh.it> |
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Hi,
"Thang Q. Nguyen" <tqnguyen@apm.com> writes:
> From: "Thang Q. Nguyen" <tqnguyen@apm.com>
>
> Add 64-bit DMA operation support to the USB DWC3 driver.
> First attempt to set the coherent DMA mask for 64-bit DMA.
> If that failed, attempt again with 32-bit DMA.
>
> Changes from v2:
> - None.
>
> Changes from v1:
> - Remove WARN_ON if dma_mask is NULL
these changes lines should be between the tearline (---) and diffstat
below.
> Signed-off-by: Thang Q. Nguyen <tqnguyen@apm.com>
> ---
> drivers/usb/dwc3/core.c | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index de5e01f..2479c24 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -831,6 +831,21 @@ static int dwc3_probe(struct platform_device *pdev)
> dwc->mem = mem;
> dwc->dev = dev;
>
> + /* Try to set 64-bit DMA first */
> + if (!pdev->dev.dma_mask)
> + /* Platform did not initialize dma_mask */
> + ret = dma_coerce_mask_and_coherent(&pdev->dev,
> + DMA_BIT_MASK(64));
> + else
> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
> +
> + /* If seting 64-bit DMA mask fails, fall back to 32-bit DMA mask */
> + if (ret) {
> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> + if (ret)
> + return ret;
> + }
Also, why is it so that you need this now ? glue layers are copying dma
mask from parent device and that should be set properly. This really
shouldn't be necessary in dwc3-core; it would mean that glue layer
didn't set this device up properly.
--
balbi
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| From | "Thang Q. Nguyen" <tqnguyen@apm.com> |
|---|---|
| Date | 2016-03-31 09:40 +0200 |
| Message-ID | <riFmW-1xL-19@gated-at.bofh.it> |
| In reply to | #1367199 |
Hi Balbi,
If CONFIG_DMA_CMA=y, dma mask is set properly. The issue just happen
when CONFIG_DMA_CMA is not set. In this case, dma mask is not set and
we need this code to check if dma mask should be manually set to 32 or
64.
----
Thang
On Wed, Mar 30, 2016 at 8:09 PM, Felipe Balbi
<felipe.balbi@linux.intel.com> wrote:
>
> Hi,
>
> "Thang Q. Nguyen" <tqnguyen@apm.com> writes:
>> From: "Thang Q. Nguyen" <tqnguyen@apm.com>
>>
>> Add 64-bit DMA operation support to the USB DWC3 driver.
>> First attempt to set the coherent DMA mask for 64-bit DMA.
>> If that failed, attempt again with 32-bit DMA.
>>
>> Changes from v2:
>> - None.
>>
>> Changes from v1:
>> - Remove WARN_ON if dma_mask is NULL
>
> these changes lines should be between the tearline (---) and diffstat
> below.
>
>> Signed-off-by: Thang Q. Nguyen <tqnguyen@apm.com>
>> ---
>> drivers/usb/dwc3/core.c | 15 +++++++++++++++
>> 1 file changed, 15 insertions(+)
>>
>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>> index de5e01f..2479c24 100644
>> --- a/drivers/usb/dwc3/core.c
>> +++ b/drivers/usb/dwc3/core.c
>> @@ -831,6 +831,21 @@ static int dwc3_probe(struct platform_device *pdev)
>> dwc->mem = mem;
>> dwc->dev = dev;
>>
>> + /* Try to set 64-bit DMA first */
>> + if (!pdev->dev.dma_mask)
>> + /* Platform did not initialize dma_mask */
>> + ret = dma_coerce_mask_and_coherent(&pdev->dev,
>> + DMA_BIT_MASK(64));
>> + else
>> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
>> +
>> + /* If seting 64-bit DMA mask fails, fall back to 32-bit DMA mask */
>> + if (ret) {
>> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
>> + if (ret)
>> + return ret;
>> + }
>
> Also, why is it so that you need this now ? glue layers are copying dma
> mask from parent device and that should be set properly. This really
> shouldn't be necessary in dwc3-core; it would mean that glue layer
> didn't set this device up properly.
>
> --
> balbi
--
Thang Q. Nguyen | Staff SW Eng.
C: +849.7684.7606 | O: +848.3770.0640
F: +848.3770.0641 | tqnguyen@apm.com
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| From | Felipe Balbi <felipe.balbi@linux.intel.com> |
|---|---|
| Date | 2016-03-31 10:10 +0200 |
| Message-ID | <riFPY-20X-3@gated-at.bofh.it> |
| In reply to | #1367908 |
[Multipart message — attachments visible in raw view] — view raw
Hi,
(please don't top-post)
"Thang Q. Nguyen" <tqnguyen@apm.com> writes:
> Hi Balbi,
> If CONFIG_DMA_CMA=y, dma mask is set properly. The issue just happen
> when CONFIG_DMA_CMA is not set. In this case, dma mask is not set and
> we need this code to check if dma mask should be manually set to 32 or
> 64.
Can you point me to the code which has this conditional ? Why would
DMA_CMA=n mean that dma_mask isn't initialized ? According to DMA_CMA's
help text (see below) that's supposed to allow drivers to *allocate*
large contiguous buffers, but that's not the case here.
config DMA_CMA
bool "DMA Contiguous Memory Allocator"
depends on HAVE_DMA_CONTIGUOUS && CMA
help
This enables the Contiguous Memory Allocator which allows drivers
to allocate big physically-contiguous blocks of memory for use with
hardware components that do not support I/O map nor scatter-gather.
You can disable CMA by specifying "cma=0" on the kernel's command
line.
For more information see <include/linux/dma-contiguous.h>.
If unsure, say "n".
>
> ----
> Thang
>
> On Wed, Mar 30, 2016 at 8:09 PM, Felipe Balbi
> <felipe.balbi@linux.intel.com> wrote:
>>
>> Hi,
>>
>> "Thang Q. Nguyen" <tqnguyen@apm.com> writes:
>>> From: "Thang Q. Nguyen" <tqnguyen@apm.com>
>>>
>>> Add 64-bit DMA operation support to the USB DWC3 driver.
>>> First attempt to set the coherent DMA mask for 64-bit DMA.
>>> If that failed, attempt again with 32-bit DMA.
>>>
>>> Changes from v2:
>>> - None.
>>>
>>> Changes from v1:
>>> - Remove WARN_ON if dma_mask is NULL
>>
>> these changes lines should be between the tearline (---) and diffstat
>> below.
>>
>>> Signed-off-by: Thang Q. Nguyen <tqnguyen@apm.com>
>>> ---
>>> drivers/usb/dwc3/core.c | 15 +++++++++++++++
>>> 1 file changed, 15 insertions(+)
>>>
>>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>>> index de5e01f..2479c24 100644
>>> --- a/drivers/usb/dwc3/core.c
>>> +++ b/drivers/usb/dwc3/core.c
>>> @@ -831,6 +831,21 @@ static int dwc3_probe(struct platform_device *pdev)
>>> dwc->mem = mem;
>>> dwc->dev = dev;
>>>
>>> + /* Try to set 64-bit DMA first */
>>> + if (!pdev->dev.dma_mask)
>>> + /* Platform did not initialize dma_mask */
>>> + ret = dma_coerce_mask_and_coherent(&pdev->dev,
>>> + DMA_BIT_MASK(64));
>>> + else
>>> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
>>> +
>>> + /* If seting 64-bit DMA mask fails, fall back to 32-bit DMA mask */
>>> + if (ret) {
>>> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
>>> + if (ret)
>>> + return ret;
>>> + }
>>
>> Also, why is it so that you need this now ? glue layers are copying dma
>> mask from parent device and that should be set properly. This really
>> shouldn't be necessary in dwc3-core; it would mean that glue layer
>> didn't set this device up properly.
>>
>> --
>> balbi
>
>
>
> --
>
> Thang Q. Nguyen | Staff SW Eng.
>
> C: +849.7684.7606 | O: +848.3770.0640
>
> F: +848.3770.0641 | tqnguyen@apm.com
--
balbi
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