Re: [Freedreno] [PATCH 08/11] drm/msm/disp/dpu1: Add support for DSC in encoder

From: abhinavk
Date: Mon Aug 02 2021 - 20:58:06 EST


On 2021-07-14 23:52, Vinod Koul wrote:
When DSC is enabled in DT, we need to configure the encoder for DSC
configuration, calculate DSC parameters for the given timing.

This patch adds that support by adding dpu_encoder_prep_dsc() which is
invoked when DSC is enabled in DT
correct me if wrong but this commit text is not valid anymore in my opinion.
are there any params you are getting from DT now? I thought its all coming from the panel
driver directly.

Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
agree with dmitry's comment's https://patchwork.freedesktop.org/patch/444078/?series=90413&rev=2

instead of dsc being part of priv->dsc it should be per encoder.

On top of his comment, I also think that like on the newer chipsets, moving the dsc related
encoder configuration to a dpu_encoder_dce.c will help for future expansion of other topologies
and also for other compression algorithms.

---
drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 142 +++++++++++++++++++-
1 file changed, 141 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index 8d942052db8a..41140b781e66 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -21,12 +21,17 @@
#include "dpu_hw_intf.h"
#include "dpu_hw_ctl.h"
#include "dpu_hw_dspp.h"
+#include "dpu_hw_dsc.h"
#include "dpu_formats.h"
#include "dpu_encoder_phys.h"
#include "dpu_crtc.h"
#include "dpu_trace.h"
#include "dpu_core_irq.h"

+#define DSC_MODE_SPLIT_PANEL BIT(0)
+#define DSC_MODE_MULTIPLEX BIT(1)
+#define DSC_MODE_VIDEO BIT(2)
+
#define DPU_DEBUG_ENC(e, fmt, ...) DPU_DEBUG("enc%d " fmt,\
(e) ? (e)->base.base.id : -1, ##__VA_ARGS__)

@@ -135,6 +140,7 @@ enum dpu_enc_rc_states {
* @cur_slave: As above but for the slave encoder.
* @hw_pp: Handle to the pingpong blocks used for the display. No.
* pingpong blocks can be different than num_phys_encs.
+ * @hw_dsc Handle to the DSC blocks used for the display.
* @intfs_swapped: Whether or not the phys_enc interfaces have been swapped
* for partial update right-only cases, such as pingpong
* split where virtual pingpong does not generate IRQs
@@ -180,6 +186,7 @@ struct dpu_encoder_virt {
struct dpu_encoder_phys *cur_master;
struct dpu_encoder_phys *cur_slave;
struct dpu_hw_pingpong *hw_pp[MAX_CHANNELS_PER_ENC];
+ struct dpu_hw_dsc *hw_dsc[MAX_CHANNELS_PER_ENC];

bool intfs_swapped;

@@ -1008,7 +1015,8 @@ static void dpu_encoder_virt_mode_set(struct
drm_encoder *drm_enc,
struct dpu_hw_blk *hw_ctl[MAX_CHANNELS_PER_ENC];
struct dpu_hw_blk *hw_lm[MAX_CHANNELS_PER_ENC];
struct dpu_hw_blk *hw_dspp[MAX_CHANNELS_PER_ENC] = { NULL };
- int num_lm, num_ctl, num_pp;
+ struct dpu_hw_blk *hw_dsc[MAX_CHANNELS_PER_ENC];
+ int num_lm, num_ctl, num_pp, num_dsc;
int i, j;

if (!drm_enc) {
@@ -1061,11 +1069,16 @@ static void dpu_encoder_virt_mode_set(struct
drm_encoder *drm_enc,
dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
drm_enc->base.id, DPU_HW_BLK_DSPP, hw_dspp,
ARRAY_SIZE(hw_dspp));
+ num_dsc = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
+ drm_enc->base.id, DPU_HW_BLK_DSC, hw_dsc, ARRAY_SIZE(hw_dsc));

for (i = 0; i < MAX_CHANNELS_PER_ENC; i++)
dpu_enc->hw_pp[i] = i < num_pp ? to_dpu_hw_pingpong(hw_pp[i])
: NULL;

+ for (i = 0; i < MAX_CHANNELS_PER_ENC; i++)
+ dpu_enc->hw_dsc[i] = i < num_dsc ? to_dpu_hw_dsc(hw_dsc[i]) : NULL;
+
cstate = to_dpu_crtc_state(drm_crtc->state);

for (i = 0; i < num_lm; i++) {
@@ -1810,10 +1823,133 @@ static void
dpu_encoder_vsync_event_work_handler(struct kthread_work *work)
nsecs_to_jiffies(ktime_to_ns(wakeup_time)));
}

+static void
+dpu_encoder_dsc_pclk_param_calc(struct msm_display_dsc_config *dsc, u32 width)
+{
+ int slice_count, slice_per_intf;
+ int bytes_in_slice, total_bytes_per_intf;
+
+ if (!dsc || !dsc->drm->slice_width || !dsc->drm->slice_count) {
+ DPU_ERROR("Invalid DSC/slices\n");
+ return;
+ }
+
+ slice_count = dsc->drm->slice_count;
+ slice_per_intf = DIV_ROUND_UP(width, dsc->drm->slice_width);
+
+ /*
+ * If slice_count is greater than slice_per_intf then default to 1.
+ * This can happen during partial update.
+ */
+ if (slice_count > slice_per_intf)
+ slice_count = 1;
+
+ bytes_in_slice = DIV_ROUND_UP(dsc->drm->slice_width *
+ dsc->drm->bits_per_pixel, 8);
+ total_bytes_per_intf = bytes_in_slice * slice_per_intf;
+
+ dsc->eol_byte_num = total_bytes_per_intf % 3;
+ dsc->pclk_per_line = DIV_ROUND_UP(total_bytes_per_intf, 3);
+ dsc->bytes_in_slice = bytes_in_slice;
+ dsc->bytes_per_pkt = bytes_in_slice * slice_count;
+ dsc->pkt_per_line = slice_per_intf / slice_count;
+}
+
+static void
+dpu_encoder_dsc_initial_line_calc(struct msm_display_dsc_config *dsc,
+ u32 enc_ip_width)
+{
+ int ssm_delay, total_pixels, soft_slice_per_enc;
+
+ soft_slice_per_enc = enc_ip_width / dsc->drm->slice_width;
+
+ /*
+ * minimum number of initial line pixels is a sum of:
+ * 1. sub-stream multiplexer delay (83 groups for 8bpc,
+ * 91 for 10 bpc) * 3
+ * 2. for two soft slice cases, add extra sub-stream multiplexer * 3
+ * 3. the initial xmit delay
+ * 4. total pipeline delay through the "lock step" of encoder (47)
+ * 5. 6 additional pixels as the output of the rate buffer is
+ * 48 bits wide
+ */
+ ssm_delay = ((dsc->drm->bits_per_component < 10) ? 84 : 92);
+ total_pixels = ssm_delay * 3 + dsc->drm->initial_xmit_delay + 47;
+ if (soft_slice_per_enc > 1)
+ total_pixels += (ssm_delay * 3);
+ dsc->initial_lines = DIV_ROUND_UP(total_pixels, dsc->drm->slice_width);
+}
+
+static void dpu_encoder_dsc_pipe_cfg(struct dpu_hw_dsc *hw_dsc,
+ struct dpu_hw_pingpong *hw_pp,
+ struct msm_display_dsc_config *dsc,
+ u32 common_mode)
+{
+ if (hw_dsc->ops.dsc_config)
+ hw_dsc->ops.dsc_config(hw_dsc, dsc, common_mode);
+
+ if (hw_dsc->ops.dsc_config_thresh)
+ hw_dsc->ops.dsc_config_thresh(hw_dsc, dsc);
+
+ if (hw_pp->ops.setup_dsc)
+ hw_pp->ops.setup_dsc(hw_pp);
+
+ if (hw_pp->ops.enable_dsc)
+ hw_pp->ops.enable_dsc(hw_pp);
+}
+
+static void dpu_encoder_prep_dsc(struct dpu_encoder_virt *dpu_enc,
+ struct msm_display_dsc_config *dsc)
+{
+ /* coding only for 2LM, 2enc, 1 dsc config */
+ struct dpu_encoder_phys *enc_master = dpu_enc->cur_master;
+ struct dpu_hw_dsc *hw_dsc[MAX_CHANNELS_PER_ENC];
+ struct dpu_hw_pingpong *hw_pp[MAX_CHANNELS_PER_ENC];
+ int this_frame_slices;
+ int intf_ip_w, enc_ip_w;
+ int dsc_common_mode;
+ int pic_width, pic_height;
+ int i;
+
+ for (i = 0; i < MAX_CHANNELS_PER_ENC; i++) {
+ hw_pp[i] = dpu_enc->hw_pp[i];
+ hw_dsc[i] = dpu_enc->hw_dsc[i];
+
+ if (!hw_pp[i] || !hw_dsc[i]) {
+ DPU_ERROR_ENC(dpu_enc, "invalid params for DSC\n");
+ return;
+ }
+ }
+
+ dsc_common_mode = 0;
+ pic_width = dsc->drm->pic_width;
+ pic_height = dsc->drm->pic_height;
+
+ dsc_common_mode = DSC_MODE_MULTIPLEX | DSC_MODE_SPLIT_PANEL;
+ if (enc_master->intf_mode == INTF_MODE_VIDEO)
+ dsc_common_mode |= DSC_MODE_VIDEO;
+
+ this_frame_slices = pic_width / dsc->drm->slice_width;
+ intf_ip_w = this_frame_slices * dsc->drm->slice_width;
+
+ dpu_encoder_dsc_pclk_param_calc(dsc, intf_ip_w);
+
+ /*
+ * dsc merge case: when using 2 encoders for the same stream,
+ * no. of slices need to be same on both the encoders.
+ */
+ enc_ip_w = intf_ip_w / 2;
+ dpu_encoder_dsc_initial_line_calc(dsc, enc_ip_w);
+
+ for (i = 0; i < MAX_CHANNELS_PER_ENC; i++)
+ dpu_encoder_dsc_pipe_cfg(hw_dsc[i], hw_pp[i], dsc, dsc_common_mode);
+}
+
void dpu_encoder_prepare_for_kickoff(struct drm_encoder *drm_enc)
{
struct dpu_encoder_virt *dpu_enc;
struct dpu_encoder_phys *phys;
+ struct msm_drm_private *priv;
bool needs_hw_reset = false;
unsigned int i;

@@ -1841,6 +1977,10 @@ void dpu_encoder_prepare_for_kickoff(struct
drm_encoder *drm_enc)
dpu_encoder_helper_hw_reset(dpu_enc->phys_encs[i]);
}
}
+
+ priv = drm_enc->dev->dev_private;
+ if (priv->dsc)
+ dpu_encoder_prep_dsc(dpu_enc, priv->dsc);
}

void dpu_encoder_kickoff(struct drm_encoder *drm_enc)