RE: [PATCH v2] usb: cdns3: Optimize DMA request buffer allocation

2021-03-22 Thread Sanket Parmar 
Hi Peter,

> On 21-03-17 20:13:59, Sanket Parmar wrote:
> > dma_alloc_coherent() might fail on the platform with a small
> > DMA region.
> >
> > To avoid such failure in cdns3_prepare_aligned_request_buf(),
> > dma_alloc_coherent() is replaced with dma_alloc_noncoherent()
> > to allocate aligned request buffer of dynamic length.
> >
> > Reported-by: Aswath Govindraju 
> > Signed-off-by: Sanket Parmar 
> > ---
> >
> > Changelog:
> > v2:
> > - used dma_*_noncoherent() APIs
> > - changed the commit log
> >
> >  drivers/usb/cdns3/cdns3-gadget.c | 30 -
> -
> >  drivers/usb/cdns3/cdns3-gadget.h |  2 ++
> >  2 files changed, 26 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/usb/cdns3/cdns3-gadget.c b/drivers/usb/cdns3/cdns3-
> gadget.c
> > index 0b892a2..126087b 100644
> > --- a/drivers/usb/cdns3/cdns3-gadget.c
> > +++ b/drivers/usb/cdns3/cdns3-gadget.c
> > @@ -819,9 +819,15 @@ void cdns3_gadget_giveback(struct
> cdns3_endpoint *priv_ep,
> > priv_ep->dir);
> >
> > if ((priv_req->flags & REQUEST_UNALIGNED) &&
> > -   priv_ep->dir == USB_DIR_OUT && !request->status)
> > +   priv_ep->dir == USB_DIR_OUT && !request->status) {
> > +   /* Make DMA buffer CPU accessible */
> > +   dma_sync_single_for_cpu(priv_dev->sysdev,
> > +   priv_req->aligned_buf->dma,
> > +   priv_req->aligned_buf->size,
> > +   priv_req->aligned_buf->dir);
> > memcpy(request->buf, priv_req->aligned_buf->buf,
> >request->length);
> > +   }
> >
> > priv_req->flags &= ~(REQUEST_PENDING | REQUEST_UNALIGNED);
> > /* All TRBs have finished, clear the counter */
> > @@ -883,8 +889,8 @@ static void cdns3_free_aligned_request_buf(struct
> work_struct *work)
> >  * interrupts.
> >  */
> > spin_unlock_irqrestore(_dev->lock, flags);
> > -   dma_free_coherent(priv_dev->sysdev, buf->size,
> > - buf->buf, buf->dma);
> > +   dma_free_noncoherent(priv_dev->sysdev, buf-
> >size,
> > + buf->buf, buf->dma, buf->dir);
> > kfree(buf);
> > spin_lock_irqsave(_dev->lock, flags);
> > }
> > @@ -911,10 +917,13 @@ static int
> cdns3_prepare_aligned_request_buf(struct cdns3_request *priv_req)
> > return -ENOMEM;
> >
> > buf->size = priv_req->request.length;
> > +   buf->dir = usb_endpoint_dir_in(priv_ep->endpoint.desc) ?
> > +   DMA_TO_DEVICE : DMA_FROM_DEVICE;
> >
> > -   buf->buf = dma_alloc_coherent(priv_dev->sysdev,
> > +   buf->buf = dma_alloc_noncoherent(priv_dev->sysdev,
> >   buf->size,
> >   >dma,
> > + buf->dir,
> >   GFP_ATOMIC);
> > if (!buf->buf) {
> > kfree(buf);
> > @@ -936,10 +945,18 @@ static int
> cdns3_prepare_aligned_request_buf(struct cdns3_request *priv_req)
> > }
> >
> > if (priv_ep->dir == USB_DIR_IN) {
> > +   /* Make DMA buffer CPU accessible */
> > +   dma_sync_single_for_cpu(priv_dev->sysdev,
> > +   buf->dma, buf->size, buf->dir);
> > memcpy(buf->buf, priv_req->request.buf,
> >priv_req->request.length);
> > }
> >
> > +   /* Transfer DMA buffer ownership back to device */
> > +   dma_sync_single_for_device(priv_dev->sysdev,
> > +   buf->dma, buf->size, buf->dir);
> > +
> > +
> 
> One more blank line.
> 
> Otherwise, it seems OK for me.

I have remove this blank line. New patch has been posted already.

> 
> > priv_req->flags |= REQUEST_UNALIGNED;
> > trace_cdns3_prepare_aligned_request(priv_req);
> >
> > @@ -3088,9 +3105,10 @@ static void cdns3_gadget_exit(struct cdns *cdns)
> > struct cdns3_aligned_buf *buf;
> >
> > buf = cdns3_next_align_buf(_dev->aligned_buf_list);
> > -   dma_free_coherent(priv_dev->sysdev, buf->size,
> > +   dma_free_noncoherent(priv_dev->sysdev, buf->size,
> >   buf->buf,
> > - buf->dma);
> > + buf->dma,
> > + buf->dir);
> >
> > list_del(>list);
> > kfree(buf);
> > diff --git a/drivers/usb/cdns3/cdns3-gadget.h b/drivers/usb/cdns3/cdns3-
> gadget.h
> > index ecf9b91..c5660f2 100644
> > --- a/drivers/usb/cdns3/cdns3-gadget.h
> > +++ b/drivers/usb/cdns3/cdns3-gadget.h
> > @@ -12,6 +12,7 @@
> >  #ifndef __LINUX_CDNS3_GADGET
> >  #define __LINUX_CDNS3_GADGET
> >  #include 
> > +#include 
> >
> >  /*
> >   * USBSS-DEV register interface.
> > @@ -1205,6 +1206,7 @@ struct cdns3_aligned_buf {
> >

Re: [PATCH v2] usb: cdns3: Optimize DMA request buffer allocation

2021-03-20 Thread Peter Chen 
On 21-03-17 20:13:59, Sanket Parmar wrote:
> dma_alloc_coherent() might fail on the platform with a small
> DMA region.
> 
> To avoid such failure in cdns3_prepare_aligned_request_buf(),
> dma_alloc_coherent() is replaced with dma_alloc_noncoherent()
> to allocate aligned request buffer of dynamic length.
> 
> Reported-by: Aswath Govindraju 
> Signed-off-by: Sanket Parmar 
> ---
> 
> Changelog:
> v2:
> - used dma_*_noncoherent() APIs
> - changed the commit log
> 
>  drivers/usb/cdns3/cdns3-gadget.c | 30 --
>  drivers/usb/cdns3/cdns3-gadget.h |  2 ++
>  2 files changed, 26 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/usb/cdns3/cdns3-gadget.c 
> b/drivers/usb/cdns3/cdns3-gadget.c
> index 0b892a2..126087b 100644
> --- a/drivers/usb/cdns3/cdns3-gadget.c
> +++ b/drivers/usb/cdns3/cdns3-gadget.c
> @@ -819,9 +819,15 @@ void cdns3_gadget_giveback(struct cdns3_endpoint 
> *priv_ep,
>   priv_ep->dir);
>  
>   if ((priv_req->flags & REQUEST_UNALIGNED) &&
> - priv_ep->dir == USB_DIR_OUT && !request->status)
> + priv_ep->dir == USB_DIR_OUT && !request->status) {
> + /* Make DMA buffer CPU accessible */
> + dma_sync_single_for_cpu(priv_dev->sysdev,
> + priv_req->aligned_buf->dma,
> + priv_req->aligned_buf->size,
> + priv_req->aligned_buf->dir);
>   memcpy(request->buf, priv_req->aligned_buf->buf,
>  request->length);
> + }
>  
>   priv_req->flags &= ~(REQUEST_PENDING | REQUEST_UNALIGNED);
>   /* All TRBs have finished, clear the counter */
> @@ -883,8 +889,8 @@ static void cdns3_free_aligned_request_buf(struct 
> work_struct *work)
>* interrupts.
>*/
>   spin_unlock_irqrestore(_dev->lock, flags);
> - dma_free_coherent(priv_dev->sysdev, buf->size,
> -   buf->buf, buf->dma);
> + dma_free_noncoherent(priv_dev->sysdev, buf->size,
> +   buf->buf, buf->dma, buf->dir);
>   kfree(buf);
>   spin_lock_irqsave(_dev->lock, flags);
>   }
> @@ -911,10 +917,13 @@ static int cdns3_prepare_aligned_request_buf(struct 
> cdns3_request *priv_req)
>   return -ENOMEM;
>  
>   buf->size = priv_req->request.length;
> + buf->dir = usb_endpoint_dir_in(priv_ep->endpoint.desc) ?
> + DMA_TO_DEVICE : DMA_FROM_DEVICE;
>  
> - buf->buf = dma_alloc_coherent(priv_dev->sysdev,
> + buf->buf = dma_alloc_noncoherent(priv_dev->sysdev,
> buf->size,
> >dma,
> +   buf->dir,
> GFP_ATOMIC);
>   if (!buf->buf) {
>   kfree(buf);
> @@ -936,10 +945,18 @@ static int cdns3_prepare_aligned_request_buf(struct 
> cdns3_request *priv_req)
>   }
>  
>   if (priv_ep->dir == USB_DIR_IN) {
> + /* Make DMA buffer CPU accessible */
> + dma_sync_single_for_cpu(priv_dev->sysdev,
> + buf->dma, buf->size, buf->dir);
>   memcpy(buf->buf, priv_req->request.buf,
>  priv_req->request.length);
>   }
>  
> + /* Transfer DMA buffer ownership back to device */
> + dma_sync_single_for_device(priv_dev->sysdev,
> + buf->dma, buf->size, buf->dir);
> +
> +

One more blank line.

Otherwise, it seems OK for me.

>   priv_req->flags |= REQUEST_UNALIGNED;
>   trace_cdns3_prepare_aligned_request(priv_req);
>  
> @@ -3088,9 +3105,10 @@ static void cdns3_gadget_exit(struct cdns *cdns)
>   struct cdns3_aligned_buf *buf;
>  
>   buf = cdns3_next_align_buf(_dev->aligned_buf_list);
> - dma_free_coherent(priv_dev->sysdev, buf->size,
> + dma_free_noncoherent(priv_dev->sysdev, buf->size,
> buf->buf,
> -   buf->dma);
> +   buf->dma,
> +   buf->dir);
>  
>   list_del(>list);
>   kfree(buf);
> diff --git a/drivers/usb/cdns3/cdns3-gadget.h 
> b/drivers/usb/cdns3/cdns3-gadget.h
> index ecf9b91..c5660f2 100644
> --- a/drivers/usb/cdns3/cdns3-gadget.h
> +++ b/drivers/usb/cdns3/cdns3-gadget.h
> @@ -12,6 +12,7 @@
>  #ifndef __LINUX_CDNS3_GADGET
>  #define __LINUX_CDNS3_GADGET
>  #include 
> +#include 
>  
>  /*
>   * USBSS-DEV register interface.
> @@ -1205,6 +1206,7 @@ struct cdns3_aligned_buf {
>   void*buf;
>   dma_addr_t  dma;
>   u32 size;
> + enum dma_data_direction dir;
>   unsigned

Re: [PATCH v2] usb: cdns3: Optimize DMA request buffer allocation

2021-03-20 Thread Peter Chen 
On 21-03-18 07:32:45, Christoph Hellwig wrote:
> On Wed, Mar 17, 2021 at 08:13:59PM +0100, Sanket Parmar wrote:
> > dma_alloc_coherent() might fail on the platform with a small
> > DMA region.
> > 
> > To avoid such failure in cdns3_prepare_aligned_request_buf(),
> > dma_alloc_coherent() is replaced with dma_alloc_noncoherent()
> > to allocate aligned request buffer of dynamic length.
> > 
> > Reported-by: Aswath Govindraju 
> > Signed-off-by: Sanket Parmar 
> 
> Looks good to me:
> 
> Reviewed-by: Christoph Hellwig 

Hi Christoph,

I would like to confirm the dma_alloc_noncoherent allocates the memory
less than PAGE_SIZE if buffer size it would like to allocate is small
(eg, 64 bytes)? 

-- 

Thanks,
Peter Chen

Re: [PATCH v2] usb: cdns3: Optimize DMA request buffer allocation

2021-03-18 Thread Christoph Hellwig 
On Wed, Mar 17, 2021 at 08:13:59PM +0100, Sanket Parmar wrote:
> dma_alloc_coherent() might fail on the platform with a small
> DMA region.
> 
> To avoid such failure in cdns3_prepare_aligned_request_buf(),
> dma_alloc_coherent() is replaced with dma_alloc_noncoherent()
> to allocate aligned request buffer of dynamic length.
> 
> Reported-by: Aswath Govindraju 
> Signed-off-by: Sanket Parmar 

Looks good to me:

Reviewed-by: Christoph Hellwig

[PATCH v2] usb: cdns3: Optimize DMA request buffer allocation

2021-03-17 Thread Sanket Parmar 
dma_alloc_coherent() might fail on the platform with a small
DMA region.

To avoid such failure in cdns3_prepare_aligned_request_buf(),
dma_alloc_coherent() is replaced with dma_alloc_noncoherent()
to allocate aligned request buffer of dynamic length.

Reported-by: Aswath Govindraju 
Signed-off-by: Sanket Parmar 
---

Changelog:
v2:
- used dma_*_noncoherent() APIs
- changed the commit log

 drivers/usb/cdns3/cdns3-gadget.c | 30 --
 drivers/usb/cdns3/cdns3-gadget.h |  2 ++
 2 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/cdns3/cdns3-gadget.c b/drivers/usb/cdns3/cdns3-gadget.c
index 0b892a2..126087b 100644
--- a/drivers/usb/cdns3/cdns3-gadget.c
+++ b/drivers/usb/cdns3/cdns3-gadget.c
@@ -819,9 +819,15 @@ void cdns3_gadget_giveback(struct cdns3_endpoint *priv_ep,
priv_ep->dir);
 
if ((priv_req->flags & REQUEST_UNALIGNED) &&
-   priv_ep->dir == USB_DIR_OUT && !request->status)
+   priv_ep->dir == USB_DIR_OUT && !request->status) {
+   /* Make DMA buffer CPU accessible */
+   dma_sync_single_for_cpu(priv_dev->sysdev,
+   priv_req->aligned_buf->dma,
+   priv_req->aligned_buf->size,
+   priv_req->aligned_buf->dir);
memcpy(request->buf, priv_req->aligned_buf->buf,
   request->length);
+   }
 
priv_req->flags &= ~(REQUEST_PENDING | REQUEST_UNALIGNED);
/* All TRBs have finished, clear the counter */
@@ -883,8 +889,8 @@ static void cdns3_free_aligned_request_buf(struct 
work_struct *work)
 * interrupts.
 */
spin_unlock_irqrestore(_dev->lock, flags);
-   dma_free_coherent(priv_dev->sysdev, buf->size,
- buf->buf, buf->dma);
+   dma_free_noncoherent(priv_dev->sysdev, buf->size,
+ buf->buf, buf->dma, buf->dir);
kfree(buf);
spin_lock_irqsave(_dev->lock, flags);
}
@@ -911,10 +917,13 @@ static int cdns3_prepare_aligned_request_buf(struct 
cdns3_request *priv_req)
return -ENOMEM;
 
buf->size = priv_req->request.length;
+   buf->dir = usb_endpoint_dir_in(priv_ep->endpoint.desc) ?
+   DMA_TO_DEVICE : DMA_FROM_DEVICE;
 
-   buf->buf = dma_alloc_coherent(priv_dev->sysdev,
+   buf->buf = dma_alloc_noncoherent(priv_dev->sysdev,
  buf->size,
  >dma,
+ buf->dir,
  GFP_ATOMIC);
if (!buf->buf) {
kfree(buf);
@@ -936,10 +945,18 @@ static int cdns3_prepare_aligned_request_buf(struct 
cdns3_request *priv_req)
}
 
if (priv_ep->dir == USB_DIR_IN) {
+   /* Make DMA buffer CPU accessible */
+   dma_sync_single_for_cpu(priv_dev->sysdev,
+   buf->dma, buf->size, buf->dir);
memcpy(buf->buf, priv_req->request.buf,
   priv_req->request.length);
}
 
+   /* Transfer DMA buffer ownership back to device */
+   dma_sync_single_for_device(priv_dev->sysdev,
+   buf->dma, buf->size, buf->dir);
+
+
priv_req->flags |= REQUEST_UNALIGNED;
trace_cdns3_prepare_aligned_request(priv_req);
 
@@ -3088,9 +3105,10 @@ static void cdns3_gadget_exit(struct cdns *cdns)
struct cdns3_aligned_buf *buf;
 
buf = cdns3_next_align_buf(_dev->aligned_buf_list);
-   dma_free_coherent(priv_dev->sysdev, buf->size,
+   dma_free_noncoherent(priv_dev->sysdev, buf->size,
  buf->buf,
- buf->dma);
+ buf->dma,
+ buf->dir);
 
list_del(>list);
kfree(buf);
diff --git a/drivers/usb/cdns3/cdns3-gadget.h b/drivers/usb/cdns3/cdns3-gadget.h
index ecf9b91..c5660f2 100644
--- a/drivers/usb/cdns3/cdns3-gadget.h
+++ b/drivers/usb/cdns3/cdns3-gadget.h
@@ -12,6 +12,7 @@
 #ifndef __LINUX_CDNS3_GADGET
 #define __LINUX_CDNS3_GADGET
 #include 
+#include 
 
 /*
  * USBSS-DEV register interface.
@@ -1205,6 +1206,7 @@ struct cdns3_aligned_buf {
void*buf;
dma_addr_t  dma;
u32 size;
+   enum dma_data_direction dir;
unsignedin_use:1;
struct list_headlist;
 };
-- 
2.4.5