> Subject: [PATCH v3 1/4] fpga: dfl: expose feature revision from struct dfl_device
>
> From: Martin Hundebøll <mhu@xxxxxxxxxx>
>
> DFL device drivers have a common need for checking feature revision
> information from the DFL header, as well as other common DFL information
> like the already exposed feature id and type.
>
> This patch exposes the feature revision information directly via the DFL
> device data structure.
>
> Since the DFL core code has already read the DFL header, this this patch
> saves additional mmio reads from DFL device drivers too.
>
> Signed-off-by: Martin Hundebøll <mhu@xxxxxxxxxx>
Acked-by: Wu Hao <hao.wu@xxxxxxxxx>
Thanks!
Hao
> ---
>
> Changes since v2:
> * Reworded commit message as per Hao's suggestion
>
> Changes since v1:
> * This patch replaces the previous patch 2 and exposes the feature
> revision through struct dfl_device instead of a helper reading from
> io-mem
>
> drivers/fpga/dfl.c | 27 +++++++++++++++++----------
> drivers/fpga/dfl.h | 1 +
> include/linux/dfl.h | 1 +
> 3 files changed, 19 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
> index 511b20ff35a3..9381c579d1cd 100644
> --- a/drivers/fpga/dfl.c
> +++ b/drivers/fpga/dfl.c
> @@ -381,6 +381,7 @@ dfl_dev_add(struct dfl_feature_platform_data *pdata,
>
> ddev->type = feature_dev_id_type(pdev);
> ddev->feature_id = feature->id;
> + ddev->revision = feature->revision;
> ddev->cdev = pdata->dfl_cdev;
>
> /* add mmio resource */
> @@ -717,6 +718,7 @@ struct build_feature_devs_info {
> */
> struct dfl_feature_info {
> u16 fid;
> + u8 rev;
> struct resource mmio_res;
> void __iomem *ioaddr;
> struct list_head node;
> @@ -796,6 +798,7 @@ static int build_info_commit_dev(struct
> build_feature_devs_info *binfo)
> /* save resource information for each feature */
> feature->dev = fdev;
> feature->id = finfo->fid;
> + feature->revision = finfo->rev;
>
> /*
> * the FIU header feature has some fundamental functions
> (sriov
> @@ -910,19 +913,17 @@ static void build_info_free(struct
> build_feature_devs_info *binfo)
> devm_kfree(binfo->dev, binfo);
> }
>
> -static inline u32 feature_size(void __iomem *start)
> +static inline u32 feature_size(u64 value)
> {
> - u64 v = readq(start + DFH);
> - u32 ofst = FIELD_GET(DFH_NEXT_HDR_OFST, v);
> + u32 ofst = FIELD_GET(DFH_NEXT_HDR_OFST, value);
> /* workaround for private features with invalid size, use 4K instead */
> return ofst ? ofst : 4096;
> }
>
> -static u16 feature_id(void __iomem *start)
> +static u16 feature_id(u64 value)
> {
> - u64 v = readq(start + DFH);
> - u16 id = FIELD_GET(DFH_ID, v);
> - u8 type = FIELD_GET(DFH_TYPE, v);
> + u16 id = FIELD_GET(DFH_ID, value);
> + u8 type = FIELD_GET(DFH_TYPE, value);
>
> if (type == DFH_TYPE_FIU)
> return FEATURE_ID_FIU_HEADER;
> @@ -1021,10 +1022,15 @@ create_feature_instance(struct
> build_feature_devs_info *binfo,
> unsigned int irq_base, nr_irqs;
> struct dfl_feature_info *finfo;
> int ret;
> + u8 rev;
> + u64 v;
> +
> + v = readq(binfo->ioaddr + ofst);
> + rev = FIELD_GET(DFH_REVISION, v);
>
> /* read feature size and id if inputs are invalid */
> - size = size ? size : feature_size(binfo->ioaddr + ofst);
> - fid = fid ? fid : feature_id(binfo->ioaddr + ofst);
> + size = size ? size : feature_size(v);
> + fid = fid ? fid : feature_id(v);
>
> if (binfo->len - ofst < size)
> return -EINVAL;
> @@ -1038,6 +1044,7 @@ create_feature_instance(struct
> build_feature_devs_info *binfo,
> return -ENOMEM;
>
> finfo->fid = fid;
> + finfo->rev = rev;
> finfo->mmio_res.start = binfo->start + ofst;
> finfo->mmio_res.end = finfo->mmio_res.start + size - 1;
> finfo->mmio_res.flags = IORESOURCE_MEM;
> @@ -1166,7 +1173,7 @@ static int parse_feature_private(struct
> build_feature_devs_info *binfo,
> {
> if (!is_feature_dev_detected(binfo)) {
> dev_err(binfo->dev, "the private feature 0x%x does not belong
> to any AFU.\n",
> - feature_id(binfo->ioaddr + ofst));
> + feature_id(readq(binfo->ioaddr + ofst)));
> return -EINVAL;
> }
>
> diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h
> index 2b82c96ba56c..422157cfd742 100644
> --- a/drivers/fpga/dfl.h
> +++ b/drivers/fpga/dfl.h
> @@ -243,6 +243,7 @@ struct dfl_feature_irq_ctx {
> struct dfl_feature {
> struct platform_device *dev;
> u16 id;
> + u8 revision;
> int resource_index;
> void __iomem *ioaddr;
> struct dfl_feature_irq_ctx *irq_ctx;
> diff --git a/include/linux/dfl.h b/include/linux/dfl.h
> index 6cc10982351a..431636a0dc78 100644
> --- a/include/linux/dfl.h
> +++ b/include/linux/dfl.h
> @@ -38,6 +38,7 @@ struct dfl_device {
> int id;
> u16 type;
> u16 feature_id;
> + u8 revision;
> struct resource mmio_res;
> int *irqs;
> unsigned int num_irqs;
> --
> 2.31.0
