[PATCH v3 2/4] media: hevc: Embedded indexes in RPS

From: Benjamin Gaignard
Date: Thu Nov 25 2021 - 10:59:04 EST


Reference Picture Set lists provide indexes of short and long term
reference in DBP array.
Fix Hantro to not do a look up in DBP entries.
Make documentation more clear about it.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx>
---
.../media/v4l/ext-ctrls-codec.rst | 6 ++---
.../staging/media/hantro/hantro_g2_hevc_dec.c | 25 +++++--------------
2 files changed, 9 insertions(+), 22 deletions(-)

diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
index 38da33e61c3d..b12ad5b3eaba 100644
--- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
+++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
@@ -3381,15 +3381,15 @@ enum v4l2_mpeg_video_hevc_size_of_length_field -
* - __u8
- ``poc_st_curr_before[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]``
- PocStCurrBefore as described in section 8.3.2 "Decoding process for reference
- picture set.
+ picture set": provides the index of the short term before references in DPB array.
* - __u8
- ``poc_st_curr_after[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]``
- PocStCurrAfter as described in section 8.3.2 "Decoding process for reference
- picture set.
+ picture set": provides the index of the short term after references in DPB array.
* - __u8
- ``poc_lt_curr[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]``
- PocLtCurr as described in section 8.3.2 "Decoding process for reference
- picture set.
+ picture set": provides the index of the long term references in DPB array.
* - __u64
- ``flags``
- See :ref:`Decode Parameters Flags <hevc_decode_params_flags>`
diff --git a/drivers/staging/media/hantro/hantro_g2_hevc_dec.c b/drivers/staging/media/hantro/hantro_g2_hevc_dec.c
index 367d0bf7b6e9..b35f36109a6f 100644
--- a/drivers/staging/media/hantro/hantro_g2_hevc_dec.c
+++ b/drivers/staging/media/hantro/hantro_g2_hevc_dec.c
@@ -255,24 +255,11 @@ static void set_params(struct hantro_ctx *ctx)
hantro_reg_write(vpu, &g2_apf_threshold, 8);
}

-static int find_ref_pic_index(const struct v4l2_hevc_dpb_entry *dpb, int pic_order_cnt)
-{
- int i;
-
- for (i = 0; i < V4L2_HEVC_DPB_ENTRIES_NUM_MAX; i++) {
- if (dpb[i].pic_order_cnt[0] == pic_order_cnt)
- return i;
- }
-
- return 0x0;
-}
-
static void set_ref_pic_list(struct hantro_ctx *ctx)
{
const struct hantro_hevc_dec_ctrls *ctrls = &ctx->hevc_dec.ctrls;
struct hantro_dev *vpu = ctx->dev;
const struct v4l2_ctrl_hevc_decode_params *decode_params = ctrls->decode_params;
- const struct v4l2_hevc_dpb_entry *dpb = decode_params->dpb;
u32 list0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX] = {};
u32 list1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX] = {};
static const struct hantro_reg ref_pic_regs0[] = {
@@ -316,11 +303,11 @@ static void set_ref_pic_list(struct hantro_ctx *ctx)
/* List 0 contains: short term before, short term after and long term */
j = 0;
for (i = 0; i < decode_params->num_poc_st_curr_before && j < ARRAY_SIZE(list0); i++)
- list0[j++] = find_ref_pic_index(dpb, decode_params->poc_st_curr_before[i]);
+ list0[j++] = decode_params->poc_st_curr_before[i];
for (i = 0; i < decode_params->num_poc_st_curr_after && j < ARRAY_SIZE(list0); i++)
- list0[j++] = find_ref_pic_index(dpb, decode_params->poc_st_curr_after[i]);
+ list0[j++] = decode_params->poc_st_curr_after[i];
for (i = 0; i < decode_params->num_poc_lt_curr && j < ARRAY_SIZE(list0); i++)
- list0[j++] = find_ref_pic_index(dpb, decode_params->poc_lt_curr[i]);
+ list0[j++] = decode_params->poc_lt_curr[i];

/* Fill the list, copying over and over */
i = 0;
@@ -329,11 +316,11 @@ static void set_ref_pic_list(struct hantro_ctx *ctx)

j = 0;
for (i = 0; i < decode_params->num_poc_st_curr_after && j < ARRAY_SIZE(list1); i++)
- list1[j++] = find_ref_pic_index(dpb, decode_params->poc_st_curr_after[i]);
+ list1[j++] = decode_params->poc_st_curr_after[i];
for (i = 0; i < decode_params->num_poc_st_curr_before && j < ARRAY_SIZE(list1); i++)
- list1[j++] = find_ref_pic_index(dpb, decode_params->poc_st_curr_before[i]);
+ list1[j++] = decode_params->poc_st_curr_before[i];
for (i = 0; i < decode_params->num_poc_lt_curr && j < ARRAY_SIZE(list1); i++)
- list1[j++] = find_ref_pic_index(dpb, decode_params->poc_lt_curr[i]);
+ list1[j++] = decode_params->poc_lt_curr[i];

i = 0;
while (j < ARRAY_SIZE(list1))
--
2.30.2