On Sun, Mar 24, 2019 at 10:23 PM Wu Hao <hao.wu@xxxxxxxxx> wrote: Hi Hao, Looks good, one question below. > > Current driver checks if input bitstream file size is aligned or > not per PR data width (default 32bits). It requires one additional > step for end user when they generate the bitstream file, padding > extra zeros to bitstream file to align its size per PR data width, > but they don't have to as hardware will drop extra padding bytes > automatically. > > In order to simplify the user steps, this patch aligns PR buffer > size per PR data width in driver, to allow user to pass unaligned > size bitstream files to driver. > > Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx> > Signed-off-by: Wu Hao <hao.wu@xxxxxxxxx> > --- > drivers/fpga/dfl-fme-pr.c | 14 +++++++++----- > 1 file changed, 9 insertions(+), 5 deletions(-) > > diff --git a/drivers/fpga/dfl-fme-pr.c b/drivers/fpga/dfl-fme-pr.c > index d9ca955..c1fb1fe 100644 > --- a/drivers/fpga/dfl-fme-pr.c > +++ b/drivers/fpga/dfl-fme-pr.c > @@ -74,6 +74,7 @@ static int fme_pr(struct platform_device *pdev, unsigned long arg) > struct dfl_fme *fme; > unsigned long minsz; > void *buf = NULL; > + size_t length; > int ret = 0; > u64 v; > > @@ -85,9 +86,6 @@ static int fme_pr(struct platform_device *pdev, unsigned long arg) > if (port_pr.argsz < minsz || port_pr.flags) > return -EINVAL; > > - if (!IS_ALIGNED(port_pr.buffer_size, 4)) > - return -EINVAL; > - > /* get fme header region */ > fme_hdr = dfl_get_feature_ioaddr_by_id(&pdev->dev, > FME_FEATURE_ID_HEADER); > @@ -103,7 +101,13 @@ static int fme_pr(struct platform_device *pdev, unsigned long arg) > port_pr.buffer_size)) > return -EFAULT; > > - buf = vmalloc(port_pr.buffer_size); > + /* > + * align PR buffer per PR bandwidth, as HW ignores the extra padding > + * data automatically. > + */ > + length = ALIGN(port_pr.buffer_size, 4); > + > + buf = vmalloc(length); Since it may not be completely filled, would it be worthwhile to alloc a zero'ed buff? Alan > if (!buf) > return -ENOMEM; > > @@ -140,7 +144,7 @@ static int fme_pr(struct platform_device *pdev, unsigned long arg) > fpga_image_info_free(region->info); > > info->buf = buf; > - info->count = port_pr.buffer_size; > + info->count = length; > info->region_id = port_pr.port_id; > region->info = info; > > -- > 2.7.4 >
