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@xxxxxx> > > Signed-off-by: Sanket Parmar <sparmar@xxxxxxxxxxx> > > --- > > 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