Re: [PATCH v2 10/16] fpga: region: use image info as parameter for programming region

Alan Tull
2017-05-09T15:25:57Z

On Thu, Apr 20, 2017 at 9:09 AM, Alan Tull <atull@kernel.org> wrote:
> Use FPGA image info as a parameter when region code is
> programming the FPGA.
>
> This is a baby step in refactoring the FPGA region code to
> separate out common FPGA region code from FPGA region
> Device Tree overlay support.
>
> Signed-off-by: Alan Tull <atull@kernel.org>
> ---
> v2: split out from another patch
> ---
> drivers/fpga/fpga-region.c | 26 ++++++++++++++++----------
> include/linux/fpga/fpga-mgr.h | 4 ++++
> 2 files changed, 20 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
> index d6f2313..1892126 100644
> --- a/drivers/fpga/fpga-region.c
> +++ b/drivers/fpga/fpga-region.c
> @@ -223,16 +223,21 @@ static int fpga_region_get_bridges(struct fpga_region *region,
> /**
> * fpga_region_program_fpga - program FPGA
> * @region: FPGA region
> - * @overlay: device node of the overlay
> - * Program an FPGA using information in the region's fpga image info.
> + * @info: FPGA image info
> + * Program an FPGA using fpga image info.
> * Return 0 for success or negative error code.
> */
> static int fpga_region_program_fpga(struct fpga_region *region,
> - struct device_node *overlay)
> + struct fpga_image_info *info)
> {
> struct device *dev = &region->dev;
> int ret;
>
> + if (region->info) {
> + dev_err(dev, "region already programmed\n");
> + return PTR_ERR(region);
> + }
> +

Currently if region has info, that is supposed to mean that the region
is programmed. I can already see how that could be limiting. I'm
think that in v3, I'm going to change this to add a region->state or
region->status that can indicate whether the region has been
programmed. Having done that, the second parameter of this functon
can go away and region->info is used.

Alan

> region = fpga_region_get(region);
> if (IS_ERR(region)) {
> dev_err(dev, "failed to get FPGA region\n");
> @@ -245,7 +250,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
> goto err_put_region;
> }
>
> - ret = fpga_region_get_bridges(region, overlay);
> + ret = fpga_region_get_bridges(region, info->overlay);
> if (ret) {
> dev_err(dev, "failed to get FPGA bridges\n");
> goto err_unlock_mgr;
> @@ -257,7 +262,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
> goto err_put_br;
> }
>
> - ret = fpga_mgr_load(region->mgr, region->info);
> + ret = fpga_mgr_load(region->mgr, info);
> if (ret) {
> dev_err(dev, "failed to load FPGA image\n");
> goto err_put_br;
> @@ -269,6 +274,8 @@ static int fpga_region_program_fpga(struct fpga_region *region,
> goto err_put_br;
> }
>
> + region->info = info;
> +
> fpga_mgr_unlock(region->mgr);
> fpga_region_put(region);
>
> @@ -373,6 +380,8 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
> if (!info)
> return -ENOMEM;
>
> + info->overlay = nd->overlay;
> +
> /* Read FPGA region properties from the overlay */
> if (of_property_read_bool(nd->overlay, "partial-fpga-config"))
> info->flags |= FPGA_MGR_PARTIAL_RECONFIG;
> @@ -420,12 +429,9 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
> return -EINVAL;
> }
>
> - region->info = info;
> - ret = fpga_region_program_fpga(region, nd->overlay);
> - if (ret) {
> + ret = fpga_region_program_fpga(region, info);
> + if (ret)
> fpga_image_info_free(&region->dev, info);
> - region->info = NULL;
> - }
>
> return ret;
> }
> diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
> index 4e14bdb..66d0e32 100644
> --- a/include/linux/fpga/fpga-mgr.h
> +++ b/include/linux/fpga/fpga-mgr.h
> @@ -84,6 +84,7 @@ enum fpga_mgr_states {
> * @sgt: scatter/gather table containing FPGA image
> * @buf: contiguous buffer containing FPGA image
> * @count: size of buf
> + * @overlay: Device Tree overlay
> */
> struct fpga_image_info {
> u32 flags;
> @@ -94,6 +95,9 @@ struct fpga_image_info {
> struct sg_table *sgt;
> const char *buf;
> size_t count;
> +#ifdef CONFIG_OF
> + struct device_node *overlay;
> +#endif
> };
>
> /**
> --
> 2.7.4
>