On Wed, Mar 29, 2017 at 08:50:23AM +0300, Felipe Balbi wrote:
>
> Hi,
>
> Peter Chen <peter.chen@xxxxxxx> writes:
> > According to xHCI ch4.20 Scratchpad Buffers
> > A Scratchpad Buffer is a PAGESIZE block of system memory
> > located on a PAGESIZE boundary
> > ...
> > Software clears the Scratchpad Buffer to ‘0’
> >
> > So, we need to use dma pool for PAGESIZE boundary buffer, and zeroed
> > its region using dma_pool_zalloc.
>
> you're doing two separate things here...
>
> > Signed-off-by: Peter Chen <peter.chen@xxxxxxx>
> > ---
> > drivers/usb/host/xhci-mem.c | 21 +++++++++++++++------
> > drivers/usb/host/xhci.h | 1 +
> > 2 files changed, 16 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
> > index 22a03b7..56aa0a6 100644
> > --- a/drivers/usb/host/xhci-mem.c
> > +++ b/drivers/usb/host/xhci-mem.c
> > @@ -1710,12 +1710,18 @@ static int scratchpad_alloc(struct xhci_hcd *xhci, gfp_t flags)
> > goto fail_sp3;
> >
> > xhci->dcbaa->dev_context_ptrs[0] = cpu_to_le64(xhci->scratchpad->sp_dma);
> > +
> > + xhci->scratchpad_pool = dma_pool_create("xhci scratchpad buffer pool",
> > + dev, xhci->page_size,
> > + xhci->page_size, xhci->page_size);
>
> adding a DMA pool here, and ...
>
> > + if (!xhci->scratchpad_pool)
> > + goto fail_sp4;
> > +
> > for (i = 0; i < num_sp; i++) {
> > dma_addr_t dma;
> > - void *buf = dma_alloc_coherent(dev, xhci->page_size, &dma,
> > - flags);
> > + void *buf = dma_pool_zalloc(xhci->scratchpad_pool, flags, &dma);
>
> ... fixing a possible bug here.
>
I know it is two things, but after the dma pool is introduced, we need a
new API to allocate memory, do you want to me use dma_pool_alloc first,
then, change it to use dma_pool_zalloc at another patch? I am ok to do
that.
--
Best Regards,
Peter Chen
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