[PATCH] dmaengine: dw: clear LLP_[SD]_EN bits in last descriptor of a chain

[PATCH] dmaengine: dw: clear LLP_[SD]_EN bits in last descriptor of a chain

[Mans Rullgard]

The datasheet requires that the LLP_[SD]_EN bits be cleared whenever
LLP.LOC is zero, i.e. in the last descriptor of a multi-block chain.
Make the driver do this.

Signed-off-by: Mans Rullgard <mans@mansr.com>
---
 drivers/dma/dw/core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index 7067b6ddc1db..ca7cafc82f6b 100644
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -751,6 +751,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
 		prev->lli.ctllo |= DWC_CTLL_INT_EN;
 
 	prev->lli.llp = 0;
+	prev->lli.ctllo &= ~(DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
 	first->txd.flags = flags;
 	first->total_len = len;
 
@@ -912,6 +913,7 @@ slave_sg_fromdev_fill_desc:
 		prev->lli.ctllo |= DWC_CTLL_INT_EN;
 
 	prev->lli.llp = 0;
+	prev->lli.ctllo &= ~(DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
 	first->total_len = total_len;
 
 	return &first->txd;
-- 
2.6.3

Re: [PATCH] dmaengine: dw: clear LLP_[SD]_EN bits in last descriptor of a chain

[Andy Shevchenko]

On Mon, 2015-12-21 at 19:10 +0000, Mans Rullgard wrote:
> The datasheet requires that the LLP_[SD]_EN bits be cleared whenever
> LLP.LOC is zero, i.e. in the last descriptor of a multi-block chain.
> Make the driver do this.

Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

> 
> Signed-off-by: Mans Rullgard <mans@mansr.com>
> ---
>  drivers/dma/dw/core.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
> index 7067b6ddc1db..ca7cafc82f6b 100644
> --- a/drivers/dma/dw/core.c
> +++ b/drivers/dma/dw/core.c
> @@ -751,6 +751,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan,
> dma_addr_t dest, dma_addr_t src,
>  		prev->lli.ctllo |= DWC_CTLL_INT_EN;
>  
>  	prev->lli.llp = 0;
> +	prev->lli.ctllo &= ~(DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
>  	first->txd.flags = flags;
>  	first->total_len = len;
>  
> @@ -912,6 +913,7 @@ slave_sg_fromdev_fill_desc:
>  		prev->lli.ctllo |= DWC_CTLL_INT_EN;
>  
>  	prev->lli.llp = 0;
> +	prev->lli.ctllo &= ~(DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
>  	first->total_len = total_len;
>  
>  	return &first->txd;

-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy

Re: [PATCH] dmaengine: dw: clear LLP_[SD]_EN bits in last descriptor of a chain

[Viresh Kumar]

On 21-12-15, 19:10, Mans Rullgard wrote:
> The datasheet requires that the LLP_[SD]_EN bits be cleared whenever
> LLP.LOC is zero, i.e. in the last descriptor of a multi-block chain.
> Make the driver do this.
> 
> Signed-off-by: Mans Rullgard <mans@mansr.com>
> ---
>  drivers/dma/dw/core.c | 2 ++
>  1 file changed, 2 insertions(+)

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

-- 
viresh

Re: [PATCH] dmaengine: dw: clear LLP_[SD]_EN bits in last descriptor of a chain

[Shevchenko, Andriy]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset="utf-8", Size: 2405 bytes --]

On Mon, 2015-12-21 at 21:34 +0200, Andy Shevchenko wrote:
> On Mon, 2015-12-21 at 19:10 +0000, Mans Rullgard wrote:
> > The datasheet requires that the LLP_[SD]_EN bits be cleared
> > whenever
> > LLP.LOC is zero, i.e. in the last descriptor of a multi-block
> > chain.
> > Make the driver do this.
> 
> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

Vinod, I would like to postpone this patch for a while to make a bit
easier back porting of other dw_dmac changes wrt fix SATA on 460EX (*).

I will send it later in a bunch. Hope MÃ¥ns has no objections on this.

(*) Now I'm pretty sure that the main issues with SATA are a) wrong
master settings for transfers and LLP, and b) endiannes issue with
values in LLP. That's why I hope to have those patches coming first
with a proper Fixes: tag.

> 
> > 
> > Signed-off-by: Mans Rullgard <mans@mansr.com>
> > ---
> >  drivers/dma/dw/core.c | 2 ++
> >  1 file changed, 2 insertions(+)
> > 
> > diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
> > index 7067b6ddc1db..ca7cafc82f6b 100644
> > --- a/drivers/dma/dw/core.c
> > +++ b/drivers/dma/dw/core.c
> > @@ -751,6 +751,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan,
> > dma_addr_t dest, dma_addr_t src,
> >  		prev->lli.ctllo |= DWC_CTLL_INT_EN;
> >  
> >  	prev->lli.llp = 0;
> > +	prev->lli.ctllo &= ~(DWC_CTLL_LLP_D_EN |
> > DWC_CTLL_LLP_S_EN);
> >  	first->txd.flags = flags;
> >  	first->total_len = len;
> >  
> > @@ -912,6 +913,7 @@ slave_sg_fromdev_fill_desc:
> >  		prev->lli.ctllo |= DWC_CTLL_INT_EN;
> >  
> >  	prev->lli.llp = 0;
> > +	prev->lli.ctllo &= ~(DWC_CTLL_LLP_D_EN |
> > DWC_CTLL_LLP_S_EN);
> >  	first->total_len = total_len;
> >  
> >  	return &first->txd;
> 

-- 
Andy Shevchenko <andriy.shevchenko@intel.com>
Intel Finland Oy
---------------------------------------------------------------------
Intel Finland Oy
Registered Address: PL 281, 00181 Helsinki 
Business Identity Code: 0357606 - 4 
Domiciled in Helsinki 

This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.
ÿôèº{.nÇ+‰·Ÿ®‰­†+%ŠËÿ±éݶ\x17¥Šwÿº{.nÇ+‰·¥Š{±þG«éÿŠ{ayº\x1dʇڙë,j\a­¢f£¢·hšïêÿ‘êçz_è®\x03(­éšŽŠÝ¢j"ú\x1a¶^[m§ÿÿ¾\a«þG«éÿ¢¸?™¨è­Ú&£ø§~á¶iO•æ¬z·švØ^\x14\x04\x1a¶^[m§ÿÿÃ\fÿ¶ìÿ¢¸?–I¥

Re: [PATCH] dmaengine: dw: clear LLP_[SD]_EN bits in last descriptor of a chain

[Vinod Koul]

On Tue, Dec 22, 2015 at 10:24:49PM +0530, Shevchenko, Andriy wrote:
> On Mon, 2015-12-21 at 21:34 +0200, Andy Shevchenko wrote:
> > On Mon, 2015-12-21 at 19:10 +0000, Mans Rullgard wrote:
> > > The datasheet requires that the LLP_[SD]_EN bits be cleared
> > > whenever
> > > LLP.LOC is zero, i.e. in the last descriptor of a multi-block
> > > chain.
> > > Make the driver do this.
> > 
> > Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> 
> Vinod, I would like to postpone this patch for a while to make a bit
> easier back porting of other dw_dmac changes wrt fix SATA on 460EX (*).
> 
> I will send it later in a bunch. Hope Måns has no objections on this.

Okay by me as long as Måns is okay

-- 
~Vinod