diff mbox series

[1/2] usb: cdns3: Use dma_pool_* api to alloc trb pool

Message ID 1615267180-9289-1-git-send-email-sparmar@cadence.com (mailing list archive)
State New, archived
Headers show
Series [1/2] usb: cdns3: Use dma_pool_* api to alloc trb pool | expand

Commit Message

Sanket Parmar March 9, 2021, 5:19 a.m. UTC
Allocation of DMA coherent memory in atomic context using
dma_alloc_coherent() might fail on platforms with smaller
DMA region.

To fix it, dma_alloc_coherent() is replaced with dma_pool
API to allocate a smaller chunk of DMA coherent memory for
TRB rings.

Fixes: 7733f6c32e36 ("usb: cdns3: Add Cadence USB3 DRD Driver")
Reported-by: Aswath Govindraju <a-govindraju@ti.com>
Signed-off-by: Sanket Parmar <sparmar@cadence.com>
---
 drivers/usb/cdns3/cdns3-gadget.c |   42 +++++++++++++++++--------------------
 drivers/usb/cdns3/cdns3-gadget.h |    1 +
 2 files changed, 20 insertions(+), 23 deletions(-)

Comments

Peter Chen March 14, 2021, 2:49 a.m. UTC | #1
On 21-03-09 06:19:39, Sanket Parmar wrote:
> Allocation of DMA coherent memory in atomic context using
> dma_alloc_coherent() might fail on platforms with smaller
> DMA region.
> 
> To fix it, dma_alloc_coherent() is replaced with dma_pool
> API to allocate a smaller chunk of DMA coherent memory for
> TRB rings.
> 
> Fixes: 7733f6c32e36 ("usb: cdns3: Add Cadence USB3 DRD Driver")

The patch is ok, but I don't think it is a bug-fix, it is an
improvement for smaller DMA region use case.

I will apply it with deletion of above Fixes tag if you have no
more opinion.

Peter
> Reported-by: Aswath Govindraju <a-govindraju@ti.com>
> Signed-off-by: Sanket Parmar <sparmar@cadence.com>
> ---
>  drivers/usb/cdns3/cdns3-gadget.c |   42 +++++++++++++++++--------------------
>  drivers/usb/cdns3/cdns3-gadget.h |    1 +
>  2 files changed, 20 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/usb/cdns3/cdns3-gadget.c b/drivers/usb/cdns3/cdns3-gadget.c
> index 582bfec..5f51215 100644
> --- a/drivers/usb/cdns3/cdns3-gadget.c
> +++ b/drivers/usb/cdns3/cdns3-gadget.c
> @@ -59,6 +59,7 @@
>  #include <linux/dma-mapping.h>
>  #include <linux/usb/gadget.h>
>  #include <linux/module.h>
> +#include <linux/dmapool.h>
>  #include <linux/iopoll.h>
>  
>  #include "core.h"
> @@ -190,29 +191,13 @@ dma_addr_t cdns3_trb_virt_to_dma(struct cdns3_endpoint *priv_ep,
>  	return priv_ep->trb_pool_dma + offset;
>  }
>  
> -static int cdns3_ring_size(struct cdns3_endpoint *priv_ep)
> -{
> -	switch (priv_ep->type) {
> -	case USB_ENDPOINT_XFER_ISOC:
> -		return TRB_ISO_RING_SIZE;
> -	case USB_ENDPOINT_XFER_CONTROL:
> -		return TRB_CTRL_RING_SIZE;
> -	default:
> -		if (priv_ep->use_streams)
> -			return TRB_STREAM_RING_SIZE;
> -		else
> -			return TRB_RING_SIZE;
> -	}
> -}
> -
>  static void cdns3_free_trb_pool(struct cdns3_endpoint *priv_ep)
>  {
>  	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
>  
>  	if (priv_ep->trb_pool) {
> -		dma_free_coherent(priv_dev->sysdev,
> -				  cdns3_ring_size(priv_ep),
> -				  priv_ep->trb_pool, priv_ep->trb_pool_dma);
> +		dma_pool_free(priv_dev->eps_dma_pool,
> +			      priv_ep->trb_pool, priv_ep->trb_pool_dma);
>  		priv_ep->trb_pool = NULL;
>  	}
>  }
> @@ -226,7 +211,7 @@ static void cdns3_free_trb_pool(struct cdns3_endpoint *priv_ep)
>  int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep)
>  {
>  	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
> -	int ring_size = cdns3_ring_size(priv_ep);
> +	int ring_size = TRB_RING_SIZE;
>  	int num_trbs = ring_size / TRB_SIZE;
>  	struct cdns3_trb *link_trb;
>  
> @@ -234,10 +219,10 @@ int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep)
>  		cdns3_free_trb_pool(priv_ep);
>  
>  	if (!priv_ep->trb_pool) {
> -		priv_ep->trb_pool = dma_alloc_coherent(priv_dev->sysdev,
> -						       ring_size,
> -						       &priv_ep->trb_pool_dma,
> -						       GFP_DMA32 | GFP_ATOMIC);
> +		priv_ep->trb_pool = dma_pool_alloc(priv_dev->eps_dma_pool,
> +						   GFP_DMA32 | GFP_ATOMIC,
> +						   &priv_ep->trb_pool_dma);
> +
>  		if (!priv_ep->trb_pool)
>  			return -ENOMEM;
>  
> @@ -3113,6 +3098,7 @@ static void cdns3_gadget_exit(struct cdns *cdns)
>  
>  	dma_free_coherent(priv_dev->sysdev, 8, priv_dev->setup_buf,
>  			  priv_dev->setup_dma);
> +	dma_pool_destroy(priv_dev->eps_dma_pool);
>  
>  	kfree(priv_dev->zlp_buf);
>  	usb_put_gadget(&priv_dev->gadget);
> @@ -3185,6 +3171,14 @@ static int cdns3_gadget_start(struct cdns *cdns)
>  	/* initialize endpoint container */
>  	INIT_LIST_HEAD(&priv_dev->gadget.ep_list);
>  	INIT_LIST_HEAD(&priv_dev->aligned_buf_list);
> +	priv_dev->eps_dma_pool = dma_pool_create("cdns3_eps_dma_pool",
> +						 priv_dev->sysdev,
> +						 TRB_RING_SIZE, 8, 0);
> +	if (!priv_dev->eps_dma_pool) {
> +		dev_err(priv_dev->dev, "Failed to create TRB dma pool\n");
> +		ret = -ENOMEM;
> +		goto err1;
> +	}
>  
>  	ret = cdns3_init_eps(priv_dev);
>  	if (ret) {
> @@ -3235,6 +3229,8 @@ static int cdns3_gadget_start(struct cdns *cdns)
>  err2:
>  	cdns3_free_all_eps(priv_dev);
>  err1:
> +	dma_pool_destroy(priv_dev->eps_dma_pool);
> +
>  	usb_put_gadget(&priv_dev->gadget);
>  	cdns->gadget_dev = NULL;
>  	return ret;
> diff --git a/drivers/usb/cdns3/cdns3-gadget.h b/drivers/usb/cdns3/cdns3-gadget.h
> index 21fa461..ecf9b91 100644
> --- a/drivers/usb/cdns3/cdns3-gadget.h
> +++ b/drivers/usb/cdns3/cdns3-gadget.h
> @@ -1298,6 +1298,7 @@ struct cdns3_device {
>  
>  	struct cdns3_usb_regs		__iomem *regs;
>  
> +	struct dma_pool			*eps_dma_pool;
>  	struct usb_ctrlrequest		*setup_buf;
>  	dma_addr_t			setup_dma;
>  	void				*zlp_buf;
> -- 
> 1.7.1
>
Sanket Parmar March 15, 2021, 6:11 a.m. UTC | #2
Hi Peter,
> 
> On 21-03-09 06:19:39, Sanket Parmar wrote:
> > Allocation of DMA coherent memory in atomic context using
> > dma_alloc_coherent() might fail on platforms with smaller
> > DMA region.
> >
> > To fix it, dma_alloc_coherent() is replaced with dma_pool
> > API to allocate a smaller chunk of DMA coherent memory for
> > TRB rings.
> >
> > Fixes: 7733f6c32e36 ("usb: cdns3: Add Cadence USB3 DRD Driver")
> 
> The patch is ok, but I don't think it is a bug-fix, it is an
> improvement for smaller DMA region use case.
> 
> I will apply it with deletion of above Fixes tag if you have no
> more opinion.
> 

Please go ahead.

Thanks,
Sanket

> Peter
> > Reported-by: Aswath Govindraju <a-govindraju@ti.com>
> > Signed-off-by: Sanket Parmar <sparmar@cadence.com>
> > ---
> >  drivers/usb/cdns3/cdns3-gadget.c |   42 +++++++++++++++++---------------
> -----
> >  drivers/usb/cdns3/cdns3-gadget.h |    1 +
> >  2 files changed, 20 insertions(+), 23 deletions(-)
> >
> > diff --git a/drivers/usb/cdns3/cdns3-gadget.c b/drivers/usb/cdns3/cdns3-
> gadget.c
> > index 582bfec..5f51215 100644
> > --- a/drivers/usb/cdns3/cdns3-gadget.c
> > +++ b/drivers/usb/cdns3/cdns3-gadget.c
> > @@ -59,6 +59,7 @@
> >  #include <linux/dma-mapping.h>
> >  #include <linux/usb/gadget.h>
> >  #include <linux/module.h>
> > +#include <linux/dmapool.h>
> >  #include <linux/iopoll.h>
> >
> >  #include "core.h"
> > @@ -190,29 +191,13 @@ dma_addr_t cdns3_trb_virt_to_dma(struct
> cdns3_endpoint *priv_ep,
> >  	return priv_ep->trb_pool_dma + offset;
> >  }
> >
> > -static int cdns3_ring_size(struct cdns3_endpoint *priv_ep)
> > -{
> > -	switch (priv_ep->type) {
> > -	case USB_ENDPOINT_XFER_ISOC:
> > -		return TRB_ISO_RING_SIZE;
> > -	case USB_ENDPOINT_XFER_CONTROL:
> > -		return TRB_CTRL_RING_SIZE;
> > -	default:
> > -		if (priv_ep->use_streams)
> > -			return TRB_STREAM_RING_SIZE;
> > -		else
> > -			return TRB_RING_SIZE;
> > -	}
> > -}
> > -
> >  static void cdns3_free_trb_pool(struct cdns3_endpoint *priv_ep)
> >  {
> >  	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
> >
> >  	if (priv_ep->trb_pool) {
> > -		dma_free_coherent(priv_dev->sysdev,
> > -				  cdns3_ring_size(priv_ep),
> > -				  priv_ep->trb_pool, priv_ep-
> >trb_pool_dma);
> > +		dma_pool_free(priv_dev->eps_dma_pool,
> > +			      priv_ep->trb_pool, priv_ep->trb_pool_dma);
> >  		priv_ep->trb_pool = NULL;
> >  	}
> >  }
> > @@ -226,7 +211,7 @@ static void cdns3_free_trb_pool(struct
> cdns3_endpoint *priv_ep)
> >  int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep)
> >  {
> >  	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
> > -	int ring_size = cdns3_ring_size(priv_ep);
> > +	int ring_size = TRB_RING_SIZE;
> >  	int num_trbs = ring_size / TRB_SIZE;
> >  	struct cdns3_trb *link_trb;
> >
> > @@ -234,10 +219,10 @@ int cdns3_allocate_trb_pool(struct
> cdns3_endpoint *priv_ep)
> >  		cdns3_free_trb_pool(priv_ep);
> >
> >  	if (!priv_ep->trb_pool) {
> > -		priv_ep->trb_pool = dma_alloc_coherent(priv_dev->sysdev,
> > -						       ring_size,
> > -						       &priv_ep-
> >trb_pool_dma,
> > -						       GFP_DMA32 |
> GFP_ATOMIC);
> > +		priv_ep->trb_pool = dma_pool_alloc(priv_dev-
> >eps_dma_pool,
> > +						   GFP_DMA32 |
> GFP_ATOMIC,
> > +						   &priv_ep->trb_pool_dma);
> > +
> >  		if (!priv_ep->trb_pool)
> >  			return -ENOMEM;
> >
> > @@ -3113,6 +3098,7 @@ static void cdns3_gadget_exit(struct cdns *cdns)
> >
> >  	dma_free_coherent(priv_dev->sysdev, 8, priv_dev->setup_buf,
> >  			  priv_dev->setup_dma);
> > +	dma_pool_destroy(priv_dev->eps_dma_pool);
> >
> >  	kfree(priv_dev->zlp_buf);
> >  	usb_put_gadget(&priv_dev->gadget);
> > @@ -3185,6 +3171,14 @@ static int cdns3_gadget_start(struct cdns *cdns)
> >  	/* initialize endpoint container */
> >  	INIT_LIST_HEAD(&priv_dev->gadget.ep_list);
> >  	INIT_LIST_HEAD(&priv_dev->aligned_buf_list);
> > +	priv_dev->eps_dma_pool =
> dma_pool_create("cdns3_eps_dma_pool",
> > +						 priv_dev->sysdev,
> > +						 TRB_RING_SIZE, 8, 0);
> > +	if (!priv_dev->eps_dma_pool) {
> > +		dev_err(priv_dev->dev, "Failed to create TRB dma pool\n");
> > +		ret = -ENOMEM;
> > +		goto err1;
> > +	}
> >
> >  	ret = cdns3_init_eps(priv_dev);
> >  	if (ret) {
> > @@ -3235,6 +3229,8 @@ static int cdns3_gadget_start(struct cdns *cdns)
> >  err2:
> >  	cdns3_free_all_eps(priv_dev);
> >  err1:
> > +	dma_pool_destroy(priv_dev->eps_dma_pool);
> > +
> >  	usb_put_gadget(&priv_dev->gadget);
> >  	cdns->gadget_dev = NULL;
> >  	return ret;
> > diff --git a/drivers/usb/cdns3/cdns3-gadget.h b/drivers/usb/cdns3/cdns3-
> gadget.h
> > index 21fa461..ecf9b91 100644
> > --- a/drivers/usb/cdns3/cdns3-gadget.h
> > +++ b/drivers/usb/cdns3/cdns3-gadget.h
> > @@ -1298,6 +1298,7 @@ struct cdns3_device {
> >
> >  	struct cdns3_usb_regs		__iomem *regs;
> >
> > +	struct dma_pool			*eps_dma_pool;
> >  	struct usb_ctrlrequest		*setup_buf;
> >  	dma_addr_t			setup_dma;
> >  	void				*zlp_buf;
> > --
> > 1.7.1
> >
> 
> --
> 
> Thanks,
> Peter Chen
diff mbox series

Patch

diff --git a/drivers/usb/cdns3/cdns3-gadget.c b/drivers/usb/cdns3/cdns3-gadget.c
index 582bfec..5f51215 100644
--- a/drivers/usb/cdns3/cdns3-gadget.c
+++ b/drivers/usb/cdns3/cdns3-gadget.c
@@ -59,6 +59,7 @@ 
 #include <linux/dma-mapping.h>
 #include <linux/usb/gadget.h>
 #include <linux/module.h>
+#include <linux/dmapool.h>
 #include <linux/iopoll.h>
 
 #include "core.h"
@@ -190,29 +191,13 @@  dma_addr_t cdns3_trb_virt_to_dma(struct cdns3_endpoint *priv_ep,
 	return priv_ep->trb_pool_dma + offset;
 }
 
-static int cdns3_ring_size(struct cdns3_endpoint *priv_ep)
-{
-	switch (priv_ep->type) {
-	case USB_ENDPOINT_XFER_ISOC:
-		return TRB_ISO_RING_SIZE;
-	case USB_ENDPOINT_XFER_CONTROL:
-		return TRB_CTRL_RING_SIZE;
-	default:
-		if (priv_ep->use_streams)
-			return TRB_STREAM_RING_SIZE;
-		else
-			return TRB_RING_SIZE;
-	}
-}
-
 static void cdns3_free_trb_pool(struct cdns3_endpoint *priv_ep)
 {
 	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
 
 	if (priv_ep->trb_pool) {
-		dma_free_coherent(priv_dev->sysdev,
-				  cdns3_ring_size(priv_ep),
-				  priv_ep->trb_pool, priv_ep->trb_pool_dma);
+		dma_pool_free(priv_dev->eps_dma_pool,
+			      priv_ep->trb_pool, priv_ep->trb_pool_dma);
 		priv_ep->trb_pool = NULL;
 	}
 }
@@ -226,7 +211,7 @@  static void cdns3_free_trb_pool(struct cdns3_endpoint *priv_ep)
 int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep)
 {
 	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
-	int ring_size = cdns3_ring_size(priv_ep);
+	int ring_size = TRB_RING_SIZE;
 	int num_trbs = ring_size / TRB_SIZE;
 	struct cdns3_trb *link_trb;
 
@@ -234,10 +219,10 @@  int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep)
 		cdns3_free_trb_pool(priv_ep);
 
 	if (!priv_ep->trb_pool) {
-		priv_ep->trb_pool = dma_alloc_coherent(priv_dev->sysdev,
-						       ring_size,
-						       &priv_ep->trb_pool_dma,
-						       GFP_DMA32 | GFP_ATOMIC);
+		priv_ep->trb_pool = dma_pool_alloc(priv_dev->eps_dma_pool,
+						   GFP_DMA32 | GFP_ATOMIC,
+						   &priv_ep->trb_pool_dma);
+
 		if (!priv_ep->trb_pool)
 			return -ENOMEM;
 
@@ -3113,6 +3098,7 @@  static void cdns3_gadget_exit(struct cdns *cdns)
 
 	dma_free_coherent(priv_dev->sysdev, 8, priv_dev->setup_buf,
 			  priv_dev->setup_dma);
+	dma_pool_destroy(priv_dev->eps_dma_pool);
 
 	kfree(priv_dev->zlp_buf);
 	usb_put_gadget(&priv_dev->gadget);
@@ -3185,6 +3171,14 @@  static int cdns3_gadget_start(struct cdns *cdns)
 	/* initialize endpoint container */
 	INIT_LIST_HEAD(&priv_dev->gadget.ep_list);
 	INIT_LIST_HEAD(&priv_dev->aligned_buf_list);
+	priv_dev->eps_dma_pool = dma_pool_create("cdns3_eps_dma_pool",
+						 priv_dev->sysdev,
+						 TRB_RING_SIZE, 8, 0);
+	if (!priv_dev->eps_dma_pool) {
+		dev_err(priv_dev->dev, "Failed to create TRB dma pool\n");
+		ret = -ENOMEM;
+		goto err1;
+	}
 
 	ret = cdns3_init_eps(priv_dev);
 	if (ret) {
@@ -3235,6 +3229,8 @@  static int cdns3_gadget_start(struct cdns *cdns)
 err2:
 	cdns3_free_all_eps(priv_dev);
 err1:
+	dma_pool_destroy(priv_dev->eps_dma_pool);
+
 	usb_put_gadget(&priv_dev->gadget);
 	cdns->gadget_dev = NULL;
 	return ret;
diff --git a/drivers/usb/cdns3/cdns3-gadget.h b/drivers/usb/cdns3/cdns3-gadget.h
index 21fa461..ecf9b91 100644
--- a/drivers/usb/cdns3/cdns3-gadget.h
+++ b/drivers/usb/cdns3/cdns3-gadget.h
@@ -1298,6 +1298,7 @@  struct cdns3_device {
 
 	struct cdns3_usb_regs		__iomem *regs;
 
+	struct dma_pool			*eps_dma_pool;
 	struct usb_ctrlrequest		*setup_buf;
 	dma_addr_t			setup_dma;
 	void				*zlp_buf;