Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1700003 > unrolled thread

Re: [PATCH v2 1/3] dmaengine: add DMA_PREP_CMD for non-Data descriptors.

Started byVinod Koul <vinod.koul@intel.com>
First post2017-07-31 14:40 +0200
Last post2017-08-02 07:00 +0200
Articles 4 — 3 participants

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.


Contents

  Re: [PATCH v2 1/3] dmaengine: add DMA_PREP_CMD for non-Data  descriptors. Vinod Koul <vinod.koul@intel.com> - 2017-07-31 14:40 +0200
    Re: [PATCH v2 1/3] dmaengine: add DMA_PREP_CMD for non-Data  descriptors. Abhishek Sahu <absahu@codeaurora.org> - 2017-07-31 15:10 +0200
    Re: [PATCH v2 1/3] dmaengine: add DMA_PREP_CMD for non-Data  descriptors. Dave Jiang <dave.jiang@intel.com> - 2017-07-31 18:40 +0200
      Re: [PATCH v2 1/3] dmaengine: add DMA_PREP_CMD for non-Data  descriptors. Vinod Koul <vinod.koul@intel.com> - 2017-08-02 07:00 +0200

#1700003 — Re: [PATCH v2 1/3] dmaengine: add DMA_PREP_CMD for non-Data descriptors.

FromVinod Koul <vinod.koul@intel.com>
Date2017-07-31 14:40 +0200
SubjectRe: [PATCH v2 1/3] dmaengine: add DMA_PREP_CMD for non-Data descriptors.
Message-ID<u9i9j-6i0-17@gated-at.bofh.it>
On Fri, Jul 28, 2017 at 09:38:56PM +0530, Abhishek Sahu wrote:
> On 2017-07-19 17:48, Abhishek Sahu wrote:
> >On 2017-07-19 15:37, Vinod Koul wrote:
> >>On Mon, Jun 26, 2017 at 06:19:27PM +0530, Abhishek Sahu wrote:
> >>>Some of the DMA controllers are capable of issuing the commands
> >>>to peripheral by the DMA. These commands can be list of register
> >>>reads/writes and its different from normal data reads/writes.
> >>>This patch adds new flag DMA_PREP_CMD in DMA API which tells
> >>>the driver that the data passed to DMA API is in command format
> >>>and DMA driver will form descriptor in the required format.
> >>>
> >>>This flag can be used by any DMA controller driver which requires
> >>>special handling for non-Data descriptors.
> >>
> >>Please add Documentation for this new flag in
> >>Documentation/dmaengine/provider.txt
> >>
> >
> > Sure. I will add update the documentation in v3.
> >
> >>>
> >>>Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
> >>>---
> >>> include/linux/dmaengine.h | 3 +++
> >>> 1 file changed, 3 insertions(+)
> >>>
> >>>diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> >>>index 5336808..bbc297e 100644
> >>>--- a/include/linux/dmaengine.h
> >>>+++ b/include/linux/dmaengine.h
> >>>@@ -186,6 +186,8 @@ struct dma_interleaved_template {
> >>>  *  on the result of this operation
> >>>  * @DMA_CTRL_REUSE: client can reuse the descriptor and submit again
> >>>till
> >>>  *  cleared or freed
> >>>+ * @DMA_PREP_CMD: tell the driver that the data passed to DMA API is
> >>>in command
> >>>+ *  format and it will be used for configuring the peripheral
> >>>registers.
> >>
> >>Can you explain what is command format..?
> >>
> >
> > The command format is not generic and its format will be dependent
> > upon DMA engine. The client drivers will give data in its own
> > command formats and this flag will be passed to DMA API’s to do
> > the parsing according to its own command format.
> >
> > Currently this flag description and name is inclined towards
> > Qualcomm BAM DMA command flag. We want to make this flag as
> > generic one so require your suggestion regarding this.
> > Will renaming this flag as DMA_PREP_NON_DATA or
> > DMA_PREP_CUSTOM make it more generic?
> >
> 
>  can we use same flag name DMA_PREP_CMD or should we
>  go for some other name?

Are you asking for using DMA_PREP_CMD, for that I think should be ok

If you asking about adding a new flag with DMA_PREP_CMD, then it would no

> 
> >>>  */
> >>> enum dma_ctrl_flags {
> >>> 	DMA_PREP_INTERRUPT = (1 << 0),
> >>>@@ -195,6 +197,7 @@ enum dma_ctrl_flags {
> >>> 	DMA_PREP_CONTINUE = (1 << 4),
> >>> 	DMA_PREP_FENCE = (1 << 5),
> >>> 	DMA_CTRL_REUSE = (1 << 6),
> >>>+	DMA_PREP_CMD = (1 << 7),
> >>> };
> >>>
> 
> 
> -- 
> Abhishek Sahu

-- 
~Vinod

[toc] | [next] | [standalone]


#1700034

FromAbhishek Sahu <absahu@codeaurora.org>
Date2017-07-31 15:10 +0200
Message-ID<u9iCm-6GI-21@gated-at.bofh.it>
In reply to#1700003
On 2017-07-31 18:04, Vinod Koul wrote:
> On Fri, Jul 28, 2017 at 09:38:56PM +0530, Abhishek Sahu wrote:
>> On 2017-07-19 17:48, Abhishek Sahu wrote:
>> >On 2017-07-19 15:37, Vinod Koul wrote:
>> >>On Mon, Jun 26, 2017 at 06:19:27PM +0530, Abhishek Sahu wrote:
>> >>>Some of the DMA controllers are capable of issuing the commands
>> >>>to peripheral by the DMA. These commands can be list of register
>> >>>reads/writes and its different from normal data reads/writes.
>> >>>This patch adds new flag DMA_PREP_CMD in DMA API which tells
>> >>>the driver that the data passed to DMA API is in command format
>> >>>and DMA driver will form descriptor in the required format.
>> >>>
>> >>>This flag can be used by any DMA controller driver which requires
>> >>>special handling for non-Data descriptors.
>> >>
>> >>Please add Documentation for this new flag in
>> >>Documentation/dmaengine/provider.txt
>> >>
>> >
>> > Sure. I will add update the documentation in v3.
>> >
>> >>>
>> >>>Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
>> >>>---
>> >>> include/linux/dmaengine.h | 3 +++
>> >>> 1 file changed, 3 insertions(+)
>> >>>
>> >>>diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
>> >>>index 5336808..bbc297e 100644
>> >>>--- a/include/linux/dmaengine.h
>> >>>+++ b/include/linux/dmaengine.h
>> >>>@@ -186,6 +186,8 @@ struct dma_interleaved_template {
>> >>>  *  on the result of this operation
>> >>>  * @DMA_CTRL_REUSE: client can reuse the descriptor and submit again
>> >>>till
>> >>>  *  cleared or freed
>> >>>+ * @DMA_PREP_CMD: tell the driver that the data passed to DMA API is
>> >>>in command
>> >>>+ *  format and it will be used for configuring the peripheral
>> >>>registers.
>> >>
>> >>Can you explain what is command format..?
>> >>
>> >
>> > The command format is not generic and its format will be dependent
>> > upon DMA engine. The client drivers will give data in its own
>> > command formats and this flag will be passed to DMA API’s to do
>> > the parsing according to its own command format.
>> >
>> > Currently this flag description and name is inclined towards
>> > Qualcomm BAM DMA command flag. We want to make this flag as
>> > generic one so require your suggestion regarding this.
>> > Will renaming this flag as DMA_PREP_NON_DATA or
>> > DMA_PREP_CUSTOM make it more generic?
>> >
>> 
>>  can we use same flag name DMA_PREP_CMD or should we
>>  go for some other name?
> 
> Are you asking for using DMA_PREP_CMD, for that I think should be ok
> 
> If you asking about adding a new flag with DMA_PREP_CMD, then it would 
> no
> 

  Thanks Vinod.

  We just want to add only one flag with name DMA_PREP_CMD and no
  other new flag.

  I will update the description for DMA_PREP_CMD in
  Documentation/dmaengine/provider.txt

>> 
>> >>>  */
>> >>> enum dma_ctrl_flags {
>> >>> 	DMA_PREP_INTERRUPT = (1 << 0),
>> >>>@@ -195,6 +197,7 @@ enum dma_ctrl_flags {
>> >>> 	DMA_PREP_CONTINUE = (1 << 4),
>> >>> 	DMA_PREP_FENCE = (1 << 5),
>> >>> 	DMA_CTRL_REUSE = (1 << 6),
>> >>>+	DMA_PREP_CMD = (1 << 7),
>> >>> };
>> >>>
>> 

[toc] | [prev] | [next] | [standalone]


#1700178

FromDave Jiang <dave.jiang@intel.com>
Date2017-07-31 18:40 +0200
Message-ID<u9lTz-6F-3@gated-at.bofh.it>
In reply to#1700003

On 07/31/2017 05:34 AM, Vinod Koul wrote:
> On Fri, Jul 28, 2017 at 09:38:56PM +0530, Abhishek Sahu wrote:
>> On 2017-07-19 17:48, Abhishek Sahu wrote:
>>> On 2017-07-19 15:37, Vinod Koul wrote:
>>>> On Mon, Jun 26, 2017 at 06:19:27PM +0530, Abhishek Sahu wrote:
>>>>> Some of the DMA controllers are capable of issuing the commands
>>>>> to peripheral by the DMA. These commands can be list of register
>>>>> reads/writes and its different from normal data reads/writes.
>>>>> This patch adds new flag DMA_PREP_CMD in DMA API which tells
>>>>> the driver that the data passed to DMA API is in command format
>>>>> and DMA driver will form descriptor in the required format.
>>>>>
>>>>> This flag can be used by any DMA controller driver which requires
>>>>> special handling for non-Data descriptors.
>>>>
>>>> Please add Documentation for this new flag in
>>>> Documentation/dmaengine/provider.txt
>>>>
>>>
>>> Sure. I will add update the documentation in v3.
>>>
>>>>>
>>>>> Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
>>>>> ---
>>>>> include/linux/dmaengine.h | 3 +++
>>>>> 1 file changed, 3 insertions(+)
>>>>>
>>>>> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
>>>>> index 5336808..bbc297e 100644
>>>>> --- a/include/linux/dmaengine.h
>>>>> +++ b/include/linux/dmaengine.h
>>>>> @@ -186,6 +186,8 @@ struct dma_interleaved_template {
>>>>>  *  on the result of this operation
>>>>>  * @DMA_CTRL_REUSE: client can reuse the descriptor and submit again
>>>>> till
>>>>>  *  cleared or freed
>>>>> + * @DMA_PREP_CMD: tell the driver that the data passed to DMA API is
>>>>> in command
>>>>> + *  format and it will be used for configuring the peripheral
>>>>> registers.
>>>>
>>>> Can you explain what is command format..?
>>>>
>>>
>>> The command format is not generic and its format will be dependent
>>> upon DMA engine. The client drivers will give data in its own
>>> command formats and this flag will be passed to DMA API’s to do
>>> the parsing according to its own command format.
>>>
>>> Currently this flag description and name is inclined towards
>>> Qualcomm BAM DMA command flag. We want to make this flag as
>>> generic one so require your suggestion regarding this.
>>> Will renaming this flag as DMA_PREP_NON_DATA or
>>> DMA_PREP_CUSTOM make it more generic?
>>>
>>
>>  can we use same flag name DMA_PREP_CMD or should we
>>  go for some other name?
> 
> Are you asking for using DMA_PREP_CMD, for that I think should be ok
> 
> If you asking about adding a new flag with DMA_PREP_CMD, then it would no

Vinod, I wonder if we should introduce a DMA_PREP_CUSTOM flag and then
reserve X number of upper flag bits to vendor specified that only they
care about. That way they can define whatever they want in the upper
bits if they need it.


> 
>>
>>>>>  */
>>>>> enum dma_ctrl_flags {
>>>>> 	DMA_PREP_INTERRUPT = (1 << 0),
>>>>> @@ -195,6 +197,7 @@ enum dma_ctrl_flags {
>>>>> 	DMA_PREP_CONTINUE = (1 << 4),
>>>>> 	DMA_PREP_FENCE = (1 << 5),
>>>>> 	DMA_CTRL_REUSE = (1 << 6),
>>>>> +	DMA_PREP_CMD = (1 << 7),
>>>>> };
>>>>>
>>
>>
>> -- 
>> Abhishek Sahu
> 

[toc] | [prev] | [next] | [standalone]


#1701714

FromVinod Koul <vinod.koul@intel.com>
Date2017-08-02 07:00 +0200
Message-ID<u9TVg-5fD-5@gated-at.bofh.it>
In reply to#1700178
On Mon, Jul 31, 2017 at 09:35:53AM -0700, Dave Jiang wrote:
> On 07/31/2017 05:34 AM, Vinod Koul wrote:

> > 
> > Are you asking for using DMA_PREP_CMD, for that I think should be ok
> > 
> > If you asking about adding a new flag with DMA_PREP_CMD, then it would no
> 
> Vinod, I wonder if we should introduce a DMA_PREP_CUSTOM flag and then
> reserve X number of upper flag bits to vendor specified that only they
> care about. That way they can define whatever they want in the upper
> bits if they need it.

Nah, that just leads to abuse :( So lets keep adding the flags generically
as and when we need them..

-- 
~Vinod

[toc] | [prev] | [standalone]


Back to top | Article view | linux.kernel


csiph-web