Re: [PATCH 3/3] drm/msm/dpu: add support for clk and bw scaling for display
From: Dmitry Baryshkov
Date: Tue Oct 27 2020 - 04:32:53 EST
Hello,
On 04/08/2020 18:40, Rob Clark wrote:
On Thu, Jul 16, 2020 at 4:36 AM Kalyan Thota <kalyan_t@xxxxxxxxxxxxxx> wrote:
This change adds support to scale src clk and bandwidth as
per composition requirements.
Interconnect registration for bw has been moved to mdp
device node from mdss to facilitate the scaling.
Changes in v1:
- Address armv7 compilation issues with the patch (Rob)
Signed-off-by: Kalyan Thota <kalyan_t@xxxxxxxxxxxxxx>
Kalyan, back in July you promised to provide a followup patchset,
removing code duplication. It's close to November now. Are there any
plans for the followup or is a forgotten topic?
Reviewed-by: Rob Clark <robdclark@xxxxxxxxxxxx>
---
drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c | 109 +++++++++++++++++++++----
drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c | 5 +-
drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h | 4 +
drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 37 ++++++++-
drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h | 4 +
drivers/gpu/drm/msm/disp/dpu1/dpu_mdss.c | 9 +-
drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c | 84 +++++++++++++++++++
drivers/gpu/drm/msm/disp/dpu1/dpu_plane.h | 4 +
8 files changed, 233 insertions(+), 23 deletions(-)
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c
index 7c230f7..e52bc44 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c
@@ -29,6 +29,74 @@ enum dpu_perf_mode {
DPU_PERF_MODE_MAX
};
+/**
+ * @_dpu_core_perf_calc_bw() - to calculate BW per crtc
+ * @kms - pointer to the dpu_kms
+ * @crtc - pointer to a crtc
+ * Return: returns aggregated BW for all planes in crtc.
+ */
+static u64 _dpu_core_perf_calc_bw(struct dpu_kms *kms,
+ struct drm_crtc *crtc)
+{
+ struct drm_plane *plane;
+ struct dpu_plane_state *pstate;
+ u64 crtc_plane_bw = 0;
+ u32 bw_factor;
+
+ drm_atomic_crtc_for_each_plane(plane, crtc) {
+ pstate = to_dpu_plane_state(plane->state);
+ if (!pstate)
+ continue;
+
+ crtc_plane_bw += pstate->plane_fetch_bw;
+ }
+
+ bw_factor = kms->catalog->perf.bw_inefficiency_factor;
+ if (bw_factor) {
+ crtc_plane_bw *= bw_factor;
+ do_div(crtc_plane_bw, 100);
+ }
+
+ return crtc_plane_bw;
+}
+
+/**
+ * _dpu_core_perf_calc_clk() - to calculate clock per crtc
+ * @kms - pointer to the dpu_kms
+ * @crtc - pointer to a crtc
+ * @state - pointer to a crtc state
+ * Return: returns max clk for all planes in crtc.
+ */
+static u64 _dpu_core_perf_calc_clk(struct dpu_kms *kms,
+ struct drm_crtc *crtc, struct drm_crtc_state *state)
+{
+ struct drm_plane *plane;
+ struct dpu_plane_state *pstate;
+ struct drm_display_mode *mode;
+ u64 crtc_clk;
+ u32 clk_factor;
+
+ mode = &state->adjusted_mode;
+
+ crtc_clk = mode->vtotal * mode->hdisplay * drm_mode_vrefresh(mode);
+
+ drm_atomic_crtc_for_each_plane(plane, crtc) {
+ pstate = to_dpu_plane_state(plane->state);
+ if (!pstate)
+ continue;
+
+ crtc_clk = max(pstate->plane_clk, crtc_clk);
+ }
+
+ clk_factor = kms->catalog->perf.clk_inefficiency_factor;
+ if (clk_factor) {
+ crtc_clk *= clk_factor;
+ do_div(crtc_clk, 100);
+ }
+
+ return crtc_clk;
+}
+
static struct dpu_kms *_dpu_crtc_get_kms(struct drm_crtc *crtc)
{
struct msm_drm_private *priv;
@@ -51,12 +119,7 @@ static void _dpu_core_perf_calc_crtc(struct dpu_kms *kms,
dpu_cstate = to_dpu_crtc_state(state);
memset(perf, 0, sizeof(struct dpu_core_perf_params));
- if (!dpu_cstate->bw_control) {
- perf->bw_ctl = kms->catalog->perf.max_bw_high *
- 1000ULL;
- perf->max_per_pipe_ib = perf->bw_ctl;
- perf->core_clk_rate = kms->perf.max_core_clk_rate;
- } else if (kms->perf.perf_tune.mode == DPU_PERF_MODE_MINIMUM) {
+ if (kms->perf.perf_tune.mode == DPU_PERF_MODE_MINIMUM) {
perf->bw_ctl = 0;
perf->max_per_pipe_ib = 0;
perf->core_clk_rate = 0;
Now bw_control is unused and can be removed alltogether.
@@ -64,6 +127,10 @@ static void _dpu_core_perf_calc_crtc(struct dpu_kms *kms,
perf->bw_ctl = kms->perf.fix_core_ab_vote;
perf->max_per_pipe_ib = kms->perf.fix_core_ib_vote;
perf->core_clk_rate = kms->perf.fix_core_clk_rate;
+ } else {
+ perf->bw_ctl = _dpu_core_perf_calc_bw(kms, crtc);
+ perf->max_per_pipe_ib = kms->catalog->perf.min_dram_ib;
+ perf->core_clk_rate = _dpu_core_perf_calc_clk(kms, crtc, state);
}
DPU_DEBUG(
@@ -115,11 +182,7 @@ int dpu_core_perf_crtc_check(struct drm_crtc *crtc,
DPU_DEBUG("crtc:%d bw:%llu ctrl:%d\n",
tmp_crtc->base.id, tmp_cstate->new_perf.bw_ctl,
tmp_cstate->bw_control);
- /*
- * For bw check only use the bw if the
- * atomic property has been already set
- */
- if (tmp_cstate->bw_control)
+
bw_sum_of_intfs += tmp_cstate->new_perf.bw_ctl;
Just a nitpick: indent is wrong.
}
@@ -131,9 +194,7 @@ int dpu_core_perf_crtc_check(struct drm_crtc *crtc,
DPU_DEBUG("final threshold bw limit = %d\n", threshold);
- if (!dpu_cstate->bw_control) {
- DPU_DEBUG("bypass bandwidth check\n");
- } else if (!threshold) {
+ if (!threshold) {
DPU_ERROR("no bandwidth limits specified\n");
return -E2BIG;
} else if (bw > threshold) {
@@ -154,7 +215,11 @@ static int _dpu_core_perf_crtc_update_bus(struct dpu_kms *kms,
= dpu_crtc_get_client_type(crtc);
struct drm_crtc *tmp_crtc;
struct dpu_crtc_state *dpu_cstate;
- int ret = 0;
+ int i, ret = 0;
+ u64 avg_bw;
+
+ if (!kms->num_paths)
+ return -EINVAL;
This broke bandwidth setting for everybody except sc7180, since
_dpu_core_perf_crtc_update_bus will be still called for them, and
returning -EINVAL here prevents dpu_core_perf_crtc_update() from setting
clock rate. Returning 0 here fixes the issue.
drm_for_each_crtc(tmp_crtc, crtc->dev) {
if (tmp_crtc->enabled &&
@@ -165,10 +230,20 @@ static int _dpu_core_perf_crtc_update_bus(struct dpu_kms *kms,
--
With best wishes
Dmitry