Re: [Freedreno] [PATCH 01/11] drm/msm/dsi: add support for dsc data
From: abhinavk
Date: Mon Aug 02 2021 - 18:55:36 EST
On 2021-07-14 23:51, Vinod Koul wrote:
Display Stream Compression (DSC) parameters need to be calculated. Add
helpers and struct msm_display_dsc_config in msm_drv for this
msm_display_dsc_config uses drm_dsc_config for DSC parameters.
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
---
Changes since RFC:
- Drop the DT parsing code
- Port dsc param calculation from downstream
drivers/gpu/drm/msm/dsi/dsi_host.c | 133 +++++++++++++++++++++++++++++
drivers/gpu/drm/msm/msm_drv.h | 21 +++++
2 files changed, 154 insertions(+)
diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c
b/drivers/gpu/drm/msm/dsi/dsi_host.c
index 8a10e4343281..e1e5d91809b5 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -30,6 +30,8 @@
#define DSI_RESET_TOGGLE_DELAY_MS 20
+static int dsi_populate_dsc_params(struct msm_display_dsc_config
*dsc);
+
static int dsi_get_version(const void __iomem *base, u32 *major, u32
*minor)
{
u32 ver;
@@ -156,6 +158,7 @@ struct msm_dsi_host {
struct regmap *sfpb;
struct drm_display_mode *mode;
+ struct msm_display_dsc_config *dsc;
/* connected device info */
struct device_node *device_node;
@@ -1744,6 +1747,136 @@ static int dsi_host_parse_lane_data(struct
msm_dsi_host *msm_host,
return -EINVAL;
}
+static u32 dsi_dsc_rc_buf_thresh[DSC_NUM_BUF_RANGES - 1] = {
+ 0x0e, 0x1c, 0x2a, 0x38, 0x46, 0x54, 0x62,
+ 0x69, 0x70, 0x77, 0x79, 0x7b, 0x7d, 0x7e
+};
+
+/* only 8bpc, 8bpp added */
+static char min_qp[DSC_NUM_BUF_RANGES] = {
+ 0, 0, 1, 1, 3, 3, 3, 3, 3, 3, 5, 5, 5, 7, 13
+};
+
+static char max_qp[DSC_NUM_BUF_RANGES] = {
+ 4, 4, 5, 6, 7, 7, 7, 8, 9, 10, 11, 12, 13, 13, 15
+};
+
+static char bpg_offset[DSC_NUM_BUF_RANGES] = {
+ 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12
+};
+
+static int dsi_populate_dsc_params(struct msm_display_dsc_config *dsc)
+{
+ int mux_words_size;
+ int groups_per_line, groups_total;
+ int min_rate_buffer_size;
+ int hrd_delay;
+ int pre_num_extra_mux_bits, num_extra_mux_bits;
+ int slice_bits;
+ int target_bpp_x16;
+ int data;
+ int final_value, final_scale;
+ int i;
+
+ dsc->drm->rc_model_size = 8192;
+ dsc->drm->first_line_bpg_offset = 12;
+ dsc->drm->rc_edge_factor = 6;
+ dsc->drm->rc_tgt_offset_high = 3;
+ dsc->drm->rc_tgt_offset_low = 3;
+ dsc->drm->simple_422 = 0;
+ dsc->drm->convert_rgb = 1;
+ dsc->drm->vbr_enable = 0;
+
+ /* handle only bpp = bpc = 8 */
+ for (i = 0; i < DSC_NUM_BUF_RANGES - 1 ; i++)
+ dsc->drm->rc_buf_thresh[i] = dsi_dsc_rc_buf_thresh[i];
+
+ for (i = 0; i < DSC_NUM_BUF_RANGES; i++) {
+ dsc->drm->rc_range_params[i].range_min_qp = min_qp[i];
+ dsc->drm->rc_range_params[i].range_max_qp = max_qp[i];
+ dsc->drm->rc_range_params[i].range_bpg_offset = bpg_offset[i];
+ }
+
+ dsc->drm->initial_offset = 6144; /* Not bpp 12 */
+ if (dsc->drm->bits_per_pixel != 8)
+ dsc->drm->initial_offset = 2048; /* bpp = 12 */
+
+ mux_words_size = 48; /* bpc == 8/10 */
+ if (dsc->drm->bits_per_component == 12)
+ mux_words_size = 64;
+
+ dsc->drm->initial_xmit_delay = 512;
+ dsc->drm->initial_scale_value = 32;
+ dsc->drm->first_line_bpg_offset = 12;
+ dsc->drm->line_buf_depth = dsc->drm->bits_per_component + 1;
+
+ /* bpc 8 */
+ dsc->drm->flatness_min_qp = 3;
+ dsc->drm->flatness_max_qp = 12;
+ dsc->det_thresh_flatness = 7 + 2 * (dsc->drm->bits_per_component -
8);
+ dsc->drm->rc_quant_incr_limit0 = 11;
+ dsc->drm->rc_quant_incr_limit1 = 11;
+ dsc->drm->mux_word_size = DSC_MUX_WORD_SIZE_8_10_BPC;
+
+ /* FIXME: need to call drm_dsc_compute_rc_parameters() so that rest
of
+ * params are calculated
+ */
+ dsc->slice_last_group_size = 3 - (dsc->drm->slice_width % 3);
+ groups_per_line = DIV_ROUND_UP(dsc->drm->slice_width, 3);
+ dsc->drm->slice_chunk_size = dsc->drm->slice_width *
dsc->drm->bits_per_pixel / 8;
+ if ((dsc->drm->slice_width * dsc->drm->bits_per_pixel) % 8)
+ dsc->drm->slice_chunk_size++;
+
+ /* rbs-min */
+ min_rate_buffer_size = dsc->drm->rc_model_size -
dsc->drm->initial_offset +
+ dsc->drm->initial_xmit_delay * dsc->drm->bits_per_pixel +
+ groups_per_line * dsc->drm->first_line_bpg_offset;
+
+ hrd_delay = DIV_ROUND_UP(min_rate_buffer_size,
dsc->drm->bits_per_pixel);
+
+ dsc->drm->initial_dec_delay = hrd_delay -
dsc->drm->initial_xmit_delay;
+
+ dsc->drm->initial_scale_value = 8 * dsc->drm->rc_model_size /
+ (dsc->drm->rc_model_size - dsc->drm->initial_offset);
+
+ slice_bits = 8 * dsc->drm->slice_chunk_size * dsc->drm->slice_height;
+
+ groups_total = groups_per_line * dsc->drm->slice_height;
+
+ data = dsc->drm->first_line_bpg_offset * 2048;
+
+ dsc->drm->nfl_bpg_offset = DIV_ROUND_UP(data, (dsc->drm->slice_height
- 1));
+
+ pre_num_extra_mux_bits = 3 * (mux_words_size + (4 *
dsc->drm->bits_per_component + 4) - 2);
+
+ num_extra_mux_bits = pre_num_extra_mux_bits - (mux_words_size -
+ ((slice_bits - pre_num_extra_mux_bits) % mux_words_size));
+
+ data = 2048 * (dsc->drm->rc_model_size - dsc->drm->initial_offset +
num_extra_mux_bits);
+ dsc->drm->slice_bpg_offset = DIV_ROUND_UP(data, groups_total);
+
+ /* bpp * 16 + 0.5 */
+ data = dsc->drm->bits_per_pixel * 16;
+ data *= 2;
+ data++;
+ data /= 2;
+ target_bpp_x16 = data;
+
+ data = (dsc->drm->initial_xmit_delay * target_bpp_x16) / 16;
+ final_value = dsc->drm->rc_model_size - data + num_extra_mux_bits;
As we discussed, can you please check why there is an additional + 8 and
/16 in the upstream final_offset calculation?
If we can eliminate or root-cause the difference in the calculations,
either this patch can be substantially reduced or
we will atleast know for future reference what was the delta and can
leave a comment.
+ dsc->drm->final_offset = final_value;
+
+ final_scale = 8 * dsc->drm->rc_model_size / (dsc->drm->rc_model_size
- final_value);
+
+
+ data = (final_scale - 9) * (dsc->drm->nfl_bpg_offset +
dsc->drm->slice_bpg_offset);
+ dsc->drm->scale_increment_interval = (2048 * dsc->drm->final_offset)
/ data;
+
+ dsc->drm->scale_decrement_interval = groups_per_line /
(dsc->drm->initial_scale_value - 8);
+
+ return 0;
+}
+
static int dsi_host_parse_dt(struct msm_dsi_host *msm_host)
{
struct device *dev = &msm_host->pdev->dev;
diff --git a/drivers/gpu/drm/msm/msm_drv.h
b/drivers/gpu/drm/msm/msm_drv.h
index 2668941df529..65bff0176b66 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -30,6 +30,7 @@
#include <drm/drm_plane_helper.h>
#include <drm/drm_probe_helper.h>
#include <drm/drm_fb_helper.h>
+#include <drm/drm_dsc.h>
#include <drm/msm_drm.h>
#include <drm/drm_gem.h>
@@ -134,6 +135,23 @@ struct msm_drm_thread {
struct kthread_worker *worker;
};
+/* DSC config */
+struct msm_display_dsc_config {
+ struct drm_dsc_config *drm;
+ u8 scr_rev;
Can scr_rev also move into drm_dsc_config? SCR itself is not QC
specific. Its just telling there was a change request
for that DSC revision.
In QC side, we only use this scr_rev to have some different tables. This
can even be true for other vendors.
So moving this to drm_dsc_config will only help.
+
+ u32 initial_lines;
+ u32 pkt_per_line;
+ u32 bytes_in_slice;
+ u32 bytes_per_pkt;
+ u32 eol_byte_num;
+ u32 pclk_per_line;
+ u32 slice_last_group_size;
+ u32 det_thresh_flatness;
+ u32 extra_width;
+ u32 pps_delay_ms;
+};
+
struct msm_drm_private {
struct drm_device *dev;
@@ -227,6 +245,9 @@ struct msm_drm_private {
/* Properties */
struct drm_property *plane_property[PLANE_PROP_MAX_NUM];
+ /* DSC configuration */
+ struct msm_display_dsc_config *dsc;
+
/* VRAM carveout, used when no IOMMU: */
struct {
unsigned long size;