2016-03-03 15:25:55

by Vinod Koul

Subject: Re: [PATCH v3 4/4] dmaengine: xilinx_vdma: Use readl_poll_timeout instead of do while loop's

On Fri, Feb 26, 2016 at 07:33:54PM +0530, Kedareswara rao Appana wrote:

> static void xilinx_vdma_halt(struct xilinx_vdma_chan *chan)
> {
> - int loop = XILINX_VDMA_LOOP_COUNT;
> + int err = 0;
> + u32 val;
>
> vdma_ctrl_clr(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RUNSTOP);
>
> /* Wait for the hardware to halt */
> - do {
> - if (vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) &
> - XILINX_VDMA_DMASR_HALTED)
> - break;
> - } while (loop--);
> + err = xilinx_vdma_poll_timeout(chan, XILINX_VDMA_REG_DMASR, val,
> + (val & XILINX_VDMA_DMASR_HALTED), 0,
> + XILINX_VDMA_LOOP_COUNT);
>
> - if (!loop) {
> + if (err) {
> dev_err(chan->dev, "Cannot stop channel %p: %x\n",
> chan, vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR));
> chan->err = true;
> @@ -576,18 +579,17 @@ static void xilinx_vdma_halt(struct xilinx_vdma_chan *chan)
> */
> static void xilinx_vdma_start(struct xilinx_vdma_chan *chan)
> {
> - int loop = XILINX_VDMA_LOOP_COUNT;
> + int err = 0;

why is this initialization required here and other places?

> + u32 val;
>
> vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RUNSTOP);
>
> /* Wait for the hardware to start */
> - do {
> - if (!(vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) &
> - XILINX_VDMA_DMASR_HALTED))
> - break;
> - } while (loop--);
> + err = xilinx_vdma_poll_timeout(chan, XILINX_VDMA_REG_DMASR, val,
> + !(val & XILINX_VDMA_DMASR_HALTED), 0,
> + XILINX_VDMA_LOOP_COUNT);
>
> - if (!loop) {
> + if (err) {
> dev_err(chan->dev, "Cannot start channel %p: %x\n",
> chan, vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR));
>
> @@ -754,21 +756,17 @@ static void xilinx_vdma_complete_descriptor(struct xilinx_vdma_chan *chan)
> */
> static int xilinx_vdma_reset(struct xilinx_vdma_chan *chan)
> {
> - int loop = XILINX_VDMA_LOOP_COUNT;
> + int err = 0;
> u32 tmp;
>
> vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RESET);
>
> - tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) &
> - XILINX_VDMA_DMACR_RESET;
> -
> /* Wait for the hardware to finish reset */
> - do {
> - tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) &
> - XILINX_VDMA_DMACR_RESET;
> - } while (loop-- && tmp);
> + err = xilinx_vdma_poll_timeout(chan, XILINX_VDMA_REG_DMACR, tmp,
> + !(tmp & XILINX_VDMA_DMACR_RESET), 0,
> + XILINX_VDMA_LOOP_COUNT);
>
> - if (!loop) {
> + if (err) {



--
~Vinod

2016-03-03 17:27:14

by Appana Durga Kedareswara rao

Subject: RE: [PATCH v3 4/4] dmaengine: xilinx_vdma: Use readl_poll_timeout instead of do while loop's

Hi Vinod,


> -----Original Message-----
> From: [email protected] [mailto:dmaengine-
> [email protected]] On Behalf Of Vinod Koul
> Sent: Thursday, March 03, 2016 9:00 PM
> To: Appana Durga Kedareswara Rao
> Cc: [email protected]; Michal Simek; Soren Brinkmann; Appana Durga
> Kedareswara Rao; [email protected];
> [email protected]; [email protected]; Anirudha
> Sarangi; [email protected]; [email protected];
> [email protected]
> Subject: Re: [PATCH v3 4/4] dmaengine: xilinx_vdma: Use readl_poll_timeout
> instead of do while loop's
>
> On Fri, Feb 26, 2016 at 07:33:54PM +0530, Kedareswara rao Appana wrote:
>
> > static void xilinx_vdma_halt(struct xilinx_vdma_chan *chan) {
> > - int loop = XILINX_VDMA_LOOP_COUNT;
> > + int err = 0;
> > + u32 val;
> >
> > vdma_ctrl_clr(chan, XILINX_VDMA_REG_DMACR,
> > XILINX_VDMA_DMACR_RUNSTOP);
> >
> > /* Wait for the hardware to halt */
> > - do {
> > - if (vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) &
> > - XILINX_VDMA_DMASR_HALTED)
> > - break;
> > - } while (loop--);
> > + err = xilinx_vdma_poll_timeout(chan, XILINX_VDMA_REG_DMASR, val,
> > + (val & XILINX_VDMA_DMASR_HALTED), 0,
> > + XILINX_VDMA_LOOP_COUNT);
> >
> > - if (!loop) {
> > + if (err) {
> > dev_err(chan->dev, "Cannot stop channel %p: %x\n",
> > chan, vdma_ctrl_read(chan,
> XILINX_VDMA_REG_DMASR));
> > chan->err = true;
> > @@ -576,18 +579,17 @@ static void xilinx_vdma_halt(struct
> xilinx_vdma_chan *chan)
> > */
> > static void xilinx_vdma_start(struct xilinx_vdma_chan *chan) {
> > - int loop = XILINX_VDMA_LOOP_COUNT;
> > + int err = 0;
>
> why is this initialization required here and other places?

Yes initialization is not required on the other mail you said you already applied this patch series.
Will send a separate patch to fix it.

Regards,
Kedar.

>
> > + u32 val;
> >
> > vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR,
> > XILINX_VDMA_DMACR_RUNSTOP);
> >
> > /* Wait for the hardware to start */
> > - do {
> > - if (!(vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) &
> > - XILINX_VDMA_DMASR_HALTED))
> > - break;
> > - } while (loop--);
> > + err = xilinx_vdma_poll_timeout(chan, XILINX_VDMA_REG_DMASR, val,
> > + !(val & XILINX_VDMA_DMASR_HALTED), 0,
> > + XILINX_VDMA_LOOP_COUNT);
> >
> > - if (!loop) {
> > + if (err) {
> > dev_err(chan->dev, "Cannot start channel %p: %x\n",
> > chan, vdma_ctrl_read(chan,
> XILINX_VDMA_REG_DMASR));
> >
> > @@ -754,21 +756,17 @@ static void xilinx_vdma_complete_descriptor(struct
> xilinx_vdma_chan *chan)
> > */
> > static int xilinx_vdma_reset(struct xilinx_vdma_chan *chan) {
> > - int loop = XILINX_VDMA_LOOP_COUNT;
> > + int err = 0;
> > u32 tmp;
> >
> > vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR,
> XILINX_VDMA_DMACR_RESET);
> >
> > - tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) &
> > - XILINX_VDMA_DMACR_RESET;
> > -
> > /* Wait for the hardware to finish reset */
> > - do {
> > - tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) &
> > - XILINX_VDMA_DMACR_RESET;
> > - } while (loop-- && tmp);
> > + err = xilinx_vdma_poll_timeout(chan, XILINX_VDMA_REG_DMACR, tmp,
> > + !(tmp & XILINX_VDMA_DMACR_RESET), 0,
> > + XILINX_VDMA_LOOP_COUNT);
> >
> > - if (!loop) {
> > + if (err) {
>
>
>
> --
> ~Vinod
> --
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