> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of Ankit
> Nautiyal
> Sent: Monday, October 16, 2023 10:51 AM
> To: intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> Subject: [PATCH 1/2] drm/i915/dsc: Use helper to calculate
> range_bpg_offset
>
> We get range_bpg_offset for different bpps based on linear-interpolation from
> values given for nearby bpps.
> Use a helper to get these values.
>
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx>
LGTM.
Reviewed-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_vdsc.c | 59 ++++++++++++-----------
> 1 file changed, 30 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c
> b/drivers/gpu/drm/i915/display/intel_vdsc.c
> index 6757dbae9ee5..708c6d4da0a2 100644
> --- a/drivers/gpu/drm/i915/display/intel_vdsc.c
> +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
> @@ -65,6 +65,13 @@ intel_vdsc_set_min_max_qp(struct drm_dsc_config
> *vdsc_cfg, int buf,
> intel_lookup_range_max_qp(bpc, buf, bpp, vdsc_cfg-
> >native_420); }
>
> +static int
> +get_range_bpg_offset(int bpp_low, int offset_low, int bpp_high, int
> +offset_high, int bpp) {
> + return offset_low + DIV_ROUND_UP((offset_high - offset_low) * (bpp -
> bpp_low),
> + (bpp_low - bpp_high));
> +}
> +
> /*
> * We are using the method provided in DSC 1.2a C-Model in codec_main.c
> * Above method use a common formula to derive values for any combination
> of DSC @@ -82,7 +89,7 @@ calculate_rc_params(struct drm_dsc_config
> *vdsc_cfg)
> int qp_bpc_modifier = (bpc - 8) * 2;
> int uncompressed_bpg_rate;
> int first_line_bpg_offset;
> - u32 res, buf_i, bpp_i;
> + u32 buf_i, bpp_i;
>
> if (vdsc_cfg->slice_height >= 8)
> first_line_bpg_offset =
> @@ -156,23 +163,19 @@ calculate_rc_params(struct drm_dsc_config
> *vdsc_cfg)
> intel_vdsc_set_min_max_qp(vdsc_cfg, buf_i, bpp_i);
>
> /* Calculate range_bpg_offset */
> - if (bpp <= 8) {
> + if (bpp <= 8)
> range_bpg_offset = ofs_und4[buf_i];
> - } else if (bpp <= 10) {
> - res = DIV_ROUND_UP(((bpp - 8) *
> - (ofs_und5[buf_i] -
> ofs_und4[buf_i])), 2);
> - range_bpg_offset = ofs_und4[buf_i] + res;
> - } else if (bpp <= 12) {
> - res = DIV_ROUND_UP(((bpp - 10) *
> - (ofs_und6[buf_i] -
> ofs_und5[buf_i])), 2);
> - range_bpg_offset = ofs_und5[buf_i] + res;
> - } else if (bpp <= 16) {
> - res = DIV_ROUND_UP(((bpp - 12) *
> - (ofs_und8[buf_i] -
> ofs_und6[buf_i])), 4);
> - range_bpg_offset = ofs_und6[buf_i] + res;
> - } else {
> + else if (bpp <= 10)
> + range_bpg_offset = get_range_bpg_offset(8,
> ofs_und4[buf_i],
> + 10,
> ofs_und5[buf_i], bpp);
> + else if (bpp <= 12)
> + range_bpg_offset = get_range_bpg_offset(10,
> ofs_und5[buf_i],
> + 12,
> ofs_und6[buf_i], bpp);
> + else if (bpp <= 16)
> + range_bpg_offset = get_range_bpg_offset(12,
> ofs_und6[buf_i],
> + 16,
> ofs_und8[buf_i], bpp);
> + else
> range_bpg_offset = ofs_und8[buf_i];
> - }
>
> vdsc_cfg->rc_range_params[buf_i].range_bpg_offset =
> range_bpg_offset &
> DSC_RANGE_BPG_OFFSET_MASK; @@ -198,21 +201,19 @@
> calculate_rc_params(struct drm_dsc_config *vdsc_cfg)
> intel_vdsc_set_min_max_qp(vdsc_cfg, buf_i, bpp_i);
>
> /* Calculate range_bpg_offset */
> - if (bpp <= 6) {
> + if (bpp <= 6)
> range_bpg_offset = ofs_und6[buf_i];
> - } else if (bpp <= 8) {
> - res = DIV_ROUND_UP(((bpp - 6) *
> - (ofs_und8[buf_i] -
> ofs_und6[buf_i])), 2);
> - range_bpg_offset = ofs_und6[buf_i] + res;
> - } else if (bpp <= 12) {
> - range_bpg_offset = ofs_und8[buf_i];
> - } else if (bpp <= 15) {
> - res = DIV_ROUND_UP(((bpp - 12) *
> - (ofs_und15[buf_i] -
> ofs_und12[buf_i])), 3);
> - range_bpg_offset = ofs_und12[buf_i] + res;
> - } else {
> + else if (bpp <= 8)
> + range_bpg_offset = get_range_bpg_offset(6,
> ofs_und6[buf_i],
> + 8,
> ofs_und8[buf_i], bpp);
> + else if (bpp <= 12)
> + range_bpg_offset = get_range_bpg_offset(8,
> ofs_und8[buf_i],
> + 12,
> ofs_und12[buf_i], bpp);
> + else if (bpp <= 15)
> + range_bpg_offset = get_range_bpg_offset(12,
> ofs_und12[buf_i],
> + 15,
> ofs_und15[buf_i], bpp);
> + else
> range_bpg_offset = ofs_und15[buf_i];
> - }
>
> vdsc_cfg->rc_range_params[buf_i].range_bpg_offset =
> range_bpg_offset &
> DSC_RANGE_BPG_OFFSET_MASK;
> --
> 2.40.1
