RE: [PATCH -next 3/8] dmaengine: xilinx_dma: Introduce xilinx_dma_get_residue
> -Original Message- > From: Radhey Shyam Pandey > Sent: Friday, September 27, 2019 10:46 AM > To: Vinod Koul > Cc: dan.j.willi...@intel.com; Michal Simek ; > nick.graum...@gmail.com; andrea.mere...@gmail.com; Appana Durga > Kedareswara Rao ; mcg...@kernel.org; > dmaeng...@vger.kernel.org; linux-kernel@vger.kernel.org > Subject: RE: [PATCH -next 3/8] dmaengine: xilinx_dma: Introduce > xilinx_dma_get_residue > > > -Original Message- > > From: Vinod Koul > > Sent: Thursday, September 26, 2019 10:48 PM > > To: Radhey Shyam Pandey > > Cc: dan.j.willi...@intel.com; Michal Simek ; > > nick.graum...@gmail.com; andrea.mere...@gmail.com; Appana Durga > > Kedareswara Rao ; mcg...@kernel.org; > > dmaeng...@vger.kernel.org; linux-kernel@vger.kernel.org > > Subject: Re: [PATCH -next 3/8] dmaengine: xilinx_dma: Introduce > > xilinx_dma_get_residue > > > > On 26-09-19, 05:52, Radhey Shyam Pandey wrote: > > > > > > > + * VDMA and simple mode do not support residue reporting, > so the > > > > > + * residue field will always be 0. > > > > > + */ > > > > > + if (chan->xdev->dma_config->dmatype == > XDMA_TYPE_VDMA || > > > > !chan->has_sg) > > > > > + return residue; > > > > > > > > why not check this in status callback? > > > Assuming we mean to move vdma and non-sg check to > > xilinx_dma_tx_status. > > > Just a thought- Keeping this check in xilinx_dma_get_residue > > > provides an abstraction and caller can simply call this func with > > > knowing about IP config specific residue calculation. Considering > > > this point does it looks ok ? > > > > well you are checking either way, so calling the lower level function > > only when you need it makes more sense! > > Sure, will do it in v2. Just noticed that xilinx_dma_get_residue() is called at the multiple places i.e one in device_tx_status and other in _complete_descriptor. To avoid code duplication, I will create a helper function to check if residue calculation is supported. > > > > -- > > ~Vinod
RE: [PATCH -next 3/8] dmaengine: xilinx_dma: Introduce xilinx_dma_get_residue
> -Original Message- > From: Vinod Koul > Sent: Thursday, September 26, 2019 10:48 PM > To: Radhey Shyam Pandey > Cc: dan.j.willi...@intel.com; Michal Simek ; > nick.graum...@gmail.com; andrea.mere...@gmail.com; Appana Durga > Kedareswara Rao ; mcg...@kernel.org; > dmaeng...@vger.kernel.org; linux-kernel@vger.kernel.org > Subject: Re: [PATCH -next 3/8] dmaengine: xilinx_dma: Introduce > xilinx_dma_get_residue > > On 26-09-19, 05:52, Radhey Shyam Pandey wrote: > > > > > +* VDMA and simple mode do not support residue reporting, so the > > > > +* residue field will always be 0. > > > > +*/ > > > > + if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA || > > > !chan->has_sg) > > > > + return residue; > > > > > > why not check this in status callback? > > Assuming we mean to move vdma and non-sg check to > xilinx_dma_tx_status. > > Just a thought- Keeping this check in xilinx_dma_get_residue provides > > an abstraction and caller can simply call this func with knowing about > > IP config specific residue calculation. Considering this point does it > > looks ok ? > > well you are checking either way, so calling the lower level function > only when you need it makes more sense! Sure, will do it in v2. > > -- > ~Vinod
Re: [PATCH -next 3/8] dmaengine: xilinx_dma: Introduce xilinx_dma_get_residue
On 26-09-19, 05:52, Radhey Shyam Pandey wrote: > > > + * VDMA and simple mode do not support residue reporting, so the > > > + * residue field will always be 0. > > > + */ > > > + if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA || > > !chan->has_sg) > > > + return residue; > > > > why not check this in status callback? > Assuming we mean to move vdma and non-sg check to xilinx_dma_tx_status. > Just a thought- Keeping this check in xilinx_dma_get_residue provides > an abstraction and caller can simply call this func with knowing about > IP config specific residue calculation. Considering this point does it > looks ok ? well you are checking either way, so calling the lower level function only when you need it makes more sense! -- ~Vinod
RE: [PATCH -next 3/8] dmaengine: xilinx_dma: Introduce xilinx_dma_get_residue
> -Original Message-
> From: Vinod Koul
> Sent: Thursday, September 26, 2019 2:31 AM
> To: Radhey Shyam Pandey
> Cc: dan.j.willi...@intel.com; Michal Simek ;
> nick.graum...@gmail.com; andrea.mere...@gmail.com; Appana Durga
> Kedareswara Rao ; mcg...@kernel.org;
> dmaeng...@vger.kernel.org; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH -next 3/8] dmaengine: xilinx_dma: Introduce
> xilinx_dma_get_residue
>
> On 05-09-19, 22:06, Radhey Shyam Pandey wrote:
> > From: Nicholas Graumann
> >
> > Introduce a function that can calculate residues for IPs that support it:
> > AXI DMA and CDMA.
> >
> > Signed-off-by: Nicholas Graumann
> > Signed-off-by: Radhey Shyam Pandey
>
> > ---
> > drivers/dma/xilinx/xilinx_dma.c | 75
> > ++---
> > 1 file changed, 56 insertions(+), 19 deletions(-)
> >
> > diff --git a/drivers/dma/xilinx/xilinx_dma.c
> > b/drivers/dma/xilinx/xilinx_dma.c index 9909bfb..4094adb 100644
> > --- a/drivers/dma/xilinx/xilinx_dma.c
> > +++ b/drivers/dma/xilinx/xilinx_dma.c
> > @@ -787,6 +787,51 @@ static void xilinx_dma_free_chan_resources(struct
> > dma_chan *dchan) }
> >
> > /**
> > + * xilinx_dma_get_residue - Compute residue for a given descriptor
> > + * @chan: Driver specific dma channel
> > + * @desc: dma transaction descriptor
> > + *
> > + * Return: The number of residue bytes for the descriptor.
> > + */
> > +static u32 xilinx_dma_get_residue(struct xilinx_dma_chan *chan,
> > + struct xilinx_dma_tx_descriptor *desc) {
> > + struct xilinx_cdma_tx_segment *cdma_seg;
> > + struct xilinx_axidma_tx_segment *axidma_seg;
> > + struct xilinx_cdma_desc_hw *cdma_hw;
> > + struct xilinx_axidma_desc_hw *axidma_hw;
> > + struct list_head *entry;
> > + u32 residue = 0;
> > +
> > + /**
>
> it should be:
> /*
> * comment...
>
Thanks for pointing it out. I will fix it in v2.
> > +* VDMA and simple mode do not support residue reporting, so the
> > +* residue field will always be 0.
> > +*/
> > + if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA ||
> !chan->has_sg)
> > + return residue;
>
> why not check this in status callback?
Assuming we mean to move vdma and non-sg check to xilinx_dma_tx_status.
Just a thought- Keeping this check in xilinx_dma_get_residue provides
an abstraction and caller can simply call this func with knowing about
IP config specific residue calculation. Considering this point does it
looks ok ?
>
> > +
> > + list_for_each(entry, >segments) {
> > + if (chan->xdev->dma_config->dmatype ==
> XDMA_TYPE_CDMA) {
> > + cdma_seg = list_entry(entry,
> > + struct xilinx_cdma_tx_segment,
> > + node);
> > + cdma_hw = _seg->hw;
> > + residue += (cdma_hw->control - cdma_hw->status)
> &
> > + chan->xdev->max_buffer_len;
> > + } else {
> > + axidma_seg = list_entry(entry,
> > + struct
> xilinx_axidma_tx_segment,
> > + node);
> > + axidma_hw = _seg->hw;
> > + residue += (axidma_hw->control - axidma_hw-
> >status) &
> > + chan->xdev->max_buffer_len;
> > + }
> > + }
> > +
> > + return residue;
> > +}
> > +
> > +/**
> > * xilinx_dma_chan_handle_cyclic - Cyclic dma callback
> > * @chan: Driver specific dma channel
> > * @desc: dma transaction descriptor
> > @@ -995,33 +1040,22 @@ static enum dma_status
> > xilinx_dma_tx_status(struct dma_chan *dchan, {
> > struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
> > struct xilinx_dma_tx_descriptor *desc;
> > - struct xilinx_axidma_tx_segment *segment;
> > - struct xilinx_axidma_desc_hw *hw;
> > enum dma_status ret;
> > unsigned long flags;
> > - u32 residue = 0;
> >
> > ret = dma_cookie_status(dchan, cookie, txstate);
> > if (ret == DMA_COMPLETE || !txstate)
> > return ret;
> >
> > - if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
> > - spin_lock_irqsave(>lock, flags);
> > + spin_lock_irqsave(>lock, flags);
> &g
Re: [PATCH -next 3/8] dmaengine: xilinx_dma: Introduce xilinx_dma_get_residue
On 05-09-19, 22:06, Radhey Shyam Pandey wrote:
> From: Nicholas Graumann
>
> Introduce a function that can calculate residues for IPs that support it:
> AXI DMA and CDMA.
>
> Signed-off-by: Nicholas Graumann
> Signed-off-by: Radhey Shyam Pandey
> ---
> drivers/dma/xilinx/xilinx_dma.c | 75
> ++---
> 1 file changed, 56 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
> index 9909bfb..4094adb 100644
> --- a/drivers/dma/xilinx/xilinx_dma.c
> +++ b/drivers/dma/xilinx/xilinx_dma.c
> @@ -787,6 +787,51 @@ static void xilinx_dma_free_chan_resources(struct
> dma_chan *dchan)
> }
>
> /**
> + * xilinx_dma_get_residue - Compute residue for a given descriptor
> + * @chan: Driver specific dma channel
> + * @desc: dma transaction descriptor
> + *
> + * Return: The number of residue bytes for the descriptor.
> + */
> +static u32 xilinx_dma_get_residue(struct xilinx_dma_chan *chan,
> + struct xilinx_dma_tx_descriptor *desc)
> +{
> + struct xilinx_cdma_tx_segment *cdma_seg;
> + struct xilinx_axidma_tx_segment *axidma_seg;
> + struct xilinx_cdma_desc_hw *cdma_hw;
> + struct xilinx_axidma_desc_hw *axidma_hw;
> + struct list_head *entry;
> + u32 residue = 0;
> +
> + /**
it should be:
/*
* comment...
> + * VDMA and simple mode do not support residue reporting, so the
> + * residue field will always be 0.
> + */
> + if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA || !chan->has_sg)
> + return residue;
why not check this in status callback?
> +
> + list_for_each(entry, >segments) {
> + if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
> + cdma_seg = list_entry(entry,
> + struct xilinx_cdma_tx_segment,
> + node);
> + cdma_hw = _seg->hw;
> + residue += (cdma_hw->control - cdma_hw->status) &
> +chan->xdev->max_buffer_len;
> + } else {
> + axidma_seg = list_entry(entry,
> + struct xilinx_axidma_tx_segment,
> + node);
> + axidma_hw = _seg->hw;
> + residue += (axidma_hw->control - axidma_hw->status) &
> +chan->xdev->max_buffer_len;
> + }
> + }
> +
> + return residue;
> +}
> +
> +/**
> * xilinx_dma_chan_handle_cyclic - Cyclic dma callback
> * @chan: Driver specific dma channel
> * @desc: dma transaction descriptor
> @@ -995,33 +1040,22 @@ static enum dma_status xilinx_dma_tx_status(struct
> dma_chan *dchan,
> {
> struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
> struct xilinx_dma_tx_descriptor *desc;
> - struct xilinx_axidma_tx_segment *segment;
> - struct xilinx_axidma_desc_hw *hw;
> enum dma_status ret;
> unsigned long flags;
> - u32 residue = 0;
>
> ret = dma_cookie_status(dchan, cookie, txstate);
> if (ret == DMA_COMPLETE || !txstate)
> return ret;
>
> - if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
> - spin_lock_irqsave(>lock, flags);
> + spin_lock_irqsave(>lock, flags);
>
> - desc = list_last_entry(>active_list,
> -struct xilinx_dma_tx_descriptor, node);
> - if (chan->has_sg) {
> - list_for_each_entry(segment, >segments, node) {
> - hw = >hw;
> - residue += (hw->control - hw->status) &
> -chan->xdev->max_buffer_len;
> - }
> - }
> - spin_unlock_irqrestore(>lock, flags);
> + desc = list_last_entry(>active_list,
> +struct xilinx_dma_tx_descriptor, node);
> + chan->residue = xilinx_dma_get_residue(chan, desc);
>
> - chan->residue = residue;
> - dma_set_residue(txstate, chan->residue);
> - }
> + spin_unlock_irqrestore(>lock, flags);
> +
> + dma_set_residue(txstate, chan->residue);
>
> return ret;
> }
> @@ -2701,12 +2735,15 @@ static int xilinx_dma_probe(struct platform_device
> *pdev)
> xilinx_dma_prep_dma_cyclic;
> xdev->common.device_prep_interleaved_dma =
> xilinx_dma_prep_interleaved;
> - /* Residue calculation is supported by only AXI DMA */
> + /* Residue calculation is supported by only AXI DMA and CDMA */
> xdev->common.residue_granularity =
> DMA_RESIDUE_GRANULARITY_SEGMENT;
> } else if (xdev->dma_config->dmatype
