[PATCH v8 01/17] drm/dp_mst: Add PBN calculation for DSC modes
mikita.lipski at amd.com
mikita.lipski at amd.com
Tue Dec 3 14:35:14 UTC 2019
From: David Francis <David.Francis at amd.com>
With DSC, bpp can be fractional in multiples of 1/16.
Change drm_dp_calc_pbn_mode to reflect this, adding a new
parameter bool dsc. When this parameter is true, treat the
bpp parameter as having units not of bits per pixel, but
1/16 of a bit per pixel
v2: Don't add separate function for this
v3: Keep the calculation in a single equation
Cc: Lyude Paul <lyude at redhat.com>
Reviewed-by: Manasi Navare <manasi.d.navare at intel.com>
Reviewed-by: Lyude Paul <lyude at redhat.com>
Reviewed-by: Harry Wentland <harry.wentland at amd.com>
Signed-off-by: David Francis <David.Francis at amd.com>
Signed-off-by: Mikita Lipski <mikita.lipski at amd.com>
---
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 +-
drivers/gpu/drm/drm_dp_mst_topology.c | 38 ++++++++++++++++++-
drivers/gpu/drm/i915/display/intel_dp_mst.c | 3 +-
drivers/gpu/drm/nouveau/dispnv50/disp.c | 2 +-
drivers/gpu/drm/radeon/radeon_dp_mst.c | 2 +-
include/drm/drm_dp_mst_helper.h | 3 +-
6 files changed, 43 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 455c51c38720..9fc03fc1017d 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -4967,7 +4967,7 @@ static int dm_encoder_helper_atomic_check(struct drm_encoder *encoder,
is_y420);
bpp = convert_dc_color_depth_into_bpc(color_depth) * 3;
clock = adjusted_mode->clock;
- dm_new_connector_state->pbn = drm_dp_calc_pbn_mode(clock, bpp);
+ dm_new_connector_state->pbn = drm_dp_calc_pbn_mode(clock, bpp, false);
}
dm_new_connector_state->vcpi_slots = drm_dp_atomic_find_vcpi_slots(state,
mst_mgr,
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index ae5809a1f19a..261e2c1828c6 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -4342,10 +4342,11 @@ EXPORT_SYMBOL(drm_dp_check_act_status);
* drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
* @clock: dot clock for the mode
* @bpp: bpp for the mode.
+ * @dsc: DSC mode. If true, bpp has units of 1/16 of a bit per pixel
*
* This uses the formula in the spec to calculate the PBN value for a mode.
*/
-int drm_dp_calc_pbn_mode(int clock, int bpp)
+int drm_dp_calc_pbn_mode(int clock, int bpp, bool dsc)
{
/*
* margin 5300ppm + 300ppm ~ 0.6% as per spec, factor is 1.006
@@ -4356,12 +4357,47 @@ int drm_dp_calc_pbn_mode(int clock, int bpp)
* peak_kbps *= (1006/1000)
* peak_kbps *= (64/54)
* peak_kbps *= 8 convert to bytes
+ *
+ * If the bpp is in units of 1/16, further divide by 16. Put this
+ * factor in the numerator rather than the denominator to avoid
+ * integer overflow
*/
+
+ if (dsc)
+ return DIV_ROUND_UP_ULL(mul_u32_u32(clock * bpp, 64 * 1006 / 16),
+ 8 * 54 * 1000 * 1000);
+
return DIV_ROUND_UP_ULL(mul_u32_u32(clock * bpp, 64 * 1006),
8 * 54 * 1000 * 1000);
+
}
EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
+static int test_calc_pbn_mode(void)
+{
+ int ret;
+ ret = drm_dp_calc_pbn_mode(154000, 30, false);
+ if (ret != 689) {
+ DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
+ 154000, 30, 689, ret);
+ return -EINVAL;
+ }
+ ret = drm_dp_calc_pbn_mode(234000, 30, false);
+ if (ret != 1047) {
+ DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
+ 234000, 30, 1047, ret);
+ return -EINVAL;
+ }
+ ret = drm_dp_calc_pbn_mode(297000, 24, false);
+ if (ret != 1063) {
+ DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
+ 297000, 24, 1063, ret);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+
/* we want to kick the TX after we've ack the up/down IRQs. */
static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
{
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index 03d1cba0b696..92be17711287 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -61,7 +61,8 @@ static int intel_dp_mst_compute_link_config(struct intel_encoder *encoder,
crtc_state->pipe_bpp = bpp;
crtc_state->pbn = drm_dp_calc_pbn_mode(adjusted_mode->crtc_clock,
- crtc_state->pipe_bpp);
+ crtc_state->pipe_bpp,
+ false);
slots = drm_dp_atomic_find_vcpi_slots(state, &intel_dp->mst_mgr,
port, crtc_state->pbn);
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index 549486f1d937..1c9e23d5a6fd 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -782,7 +782,7 @@ nv50_msto_atomic_check(struct drm_encoder *encoder,
const int bpp = connector->display_info.bpc * 3;
const int clock = crtc_state->adjusted_mode.clock;
- asyh->dp.pbn = drm_dp_calc_pbn_mode(clock, bpp);
+ asyh->dp.pbn = drm_dp_calc_pbn_mode(clock, bpp, false);
}
slots = drm_dp_atomic_find_vcpi_slots(state, &mstm->mgr,
diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c b/drivers/gpu/drm/radeon/radeon_dp_mst.c
index ee28f5b3785e..28eef9282874 100644
--- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
+++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
@@ -518,7 +518,7 @@ static bool radeon_mst_mode_fixup(struct drm_encoder *encoder,
mst_enc = radeon_encoder->enc_priv;
- mst_enc->pbn = drm_dp_calc_pbn_mode(adjusted_mode->clock, bpp);
+ mst_enc->pbn = drm_dp_calc_pbn_mode(adjusted_mode->clock, bpp, false);
mst_enc->primary->active_device = mst_enc->primary->devices & mst_enc->connector->devices;
DRM_DEBUG_KMS("setting active device to %08x from %08x %08x for encoder %d\n",
diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index d5fc90b30487..68656913cfe5 100644
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -719,8 +719,7 @@ bool drm_dp_mst_port_has_audio(struct drm_dp_mst_topology_mgr *mgr,
struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
-int drm_dp_calc_pbn_mode(int clock, int bpp);
-
+int drm_dp_calc_pbn_mode(int clock, int bpp, bool dsc);
bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_mst_port *port, int pbn, int slots);
--
2.17.1
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