Re: [PATCH v9 10/18] drm/dp_mst: Manually overwrite PBN divider for calculating timeslots
Reviewed-by: Lyude Paul
On Fri, 2019-12-13 at 15:08 -0500, mikita.lip...@amd.com wrote:
> From: Mikita Lipski
>
> [why]
> For DSC case we cannot use topology manager's PBN divider
> variable. The default divider does not take FEC into account.
> Therefore the driver has to calculate its own divider based
> on the link rate and lane count its handling, as it is hw specific.
>
> [how]
> Pass pbn_div as an argument, which is used if its more than
> zero, otherwise default topology manager's pbn_div will be used.
>
> Cc: Lyude Paul
> Cc: Harry Wentland
> Cc: Manasi Navare
> Signed-off-by: Mikita Lipski
> ---
> drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 ++-
> drivers/gpu/drm/drm_dp_mst_topology.c | 9 +++--
> drivers/gpu/drm/i915/display/intel_dp_mst.c | 2 +-
> drivers/gpu/drm/nouveau/dispnv50/disp.c | 3 ++-
> include/drm/drm_dp_mst_helper.h | 3 ++-
> 5 files changed, 14 insertions(+), 6 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 9fc03fc1017d..753a79734817 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -4972,7 +4972,8 @@ static int dm_encoder_helper_atomic_check(struct
> drm_encoder *encoder,
> dm_new_connector_state->vcpi_slots =
> drm_dp_atomic_find_vcpi_slots(state,
> mst
> _mgr,
> mst
> _port,
> -dm_
> new_connector_state->pbn);
> +dm_
> new_connector_state->pbn,
> +0);
> if (dm_new_connector_state->vcpi_slots < 0) {
> DRM_DEBUG_ATOMIC("failed finding vcpi slots: %d\n",
> (int)dm_new_connector_state->vcpi_slots);
> return dm_new_connector_state->vcpi_slots;
> diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c
> b/drivers/gpu/drm/drm_dp_mst_topology.c
> index 74bed71f7315..bb0844dfb3d2 100644
> --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> @@ -4020,6 +4020,7 @@ static int drm_dp_init_vcpi(struct
> drm_dp_mst_topology_mgr *mgr,
> * @mgr: MST topology manager for the port
> * @port: port to find vcpi slots for
> * @pbn: bandwidth required for the mode in PBN
> + * @pbn_div: divider for DSC mode that takes FEC into account
> *
> * Allocates VCPI slots to @port, replacing any previous VCPI allocations
> it
> * may have had. Any atomic drivers which support MST must call this
> function
> @@ -4046,7 +4047,8 @@ static int drm_dp_init_vcpi(struct
> drm_dp_mst_topology_mgr *mgr,
> */
> int drm_dp_atomic_find_vcpi_slots(struct drm_atomic_state *state,
> struct drm_dp_mst_topology_mgr *mgr,
> - struct drm_dp_mst_port *port, int pbn)
> + struct drm_dp_mst_port *port, int pbn,
> + int pbn_div)
> {
> struct drm_dp_mst_topology_state *topology_state;
> struct drm_dp_vcpi_allocation *pos, *vcpi = NULL;
> @@ -4079,7 +4081,10 @@ int drm_dp_atomic_find_vcpi_slots(struct
> drm_atomic_state *state,
> if (!vcpi)
> prev_slots = 0;
>
> - req_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
> + if (pbn_div <= 0)
> + pbn_div = mgr->pbn_div;
> +
> + req_slots = DIV_ROUND_UP(pbn, pbn_div);
>
> DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] [MST PORT:%p] VCPI %d -> %d\n",
>port->connector->base.id, port->connector->name,
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index 92be17711287..a068f54a6793 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -65,7 +65,7 @@ static int intel_dp_mst_compute_link_config(struct
> intel_encoder *encoder,
> false);
>
> slots = drm_dp_atomic_find_vcpi_slots(state, _dp-
> >mst_mgr,
> - port, crtc_state->pbn);
> + port, crtc_state->pbn,
> 0);
> if (slots == -EDEADLK)
> return slots;
> if (slots >= 0)
> diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> index 1c9e23d5a6fd..edb78966c5b6 100644
> --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> @@ -787,7 +787,8 @@ nv50_msto_atomic_check(struct drm_encoder *encoder,
>
> slots =
[PATCH v9 10/18] drm/dp_mst: Manually overwrite PBN divider for calculating timeslots
From: Mikita Lipski
[why]
For DSC case we cannot use topology manager's PBN divider
variable. The default divider does not take FEC into account.
Therefore the driver has to calculate its own divider based
on the link rate and lane count its handling, as it is hw specific.
[how]
Pass pbn_div as an argument, which is used if its more than
zero, otherwise default topology manager's pbn_div will be used.
Cc: Lyude Paul
Cc: Harry Wentland
Cc: Manasi Navare
Signed-off-by: Mikita Lipski
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 ++-
drivers/gpu/drm/drm_dp_mst_topology.c | 9 +++--
drivers/gpu/drm/i915/display/intel_dp_mst.c | 2 +-
drivers/gpu/drm/nouveau/dispnv50/disp.c | 3 ++-
include/drm/drm_dp_mst_helper.h | 3 ++-
5 files changed, 14 insertions(+), 6 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 9fc03fc1017d..753a79734817 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -4972,7 +4972,8 @@ static int dm_encoder_helper_atomic_check(struct
drm_encoder *encoder,
dm_new_connector_state->vcpi_slots =
drm_dp_atomic_find_vcpi_slots(state,
mst_mgr,
mst_port,
-
dm_new_connector_state->pbn);
+
dm_new_connector_state->pbn,
+ 0);
if (dm_new_connector_state->vcpi_slots < 0) {
DRM_DEBUG_ATOMIC("failed finding vcpi slots: %d\n",
(int)dm_new_connector_state->vcpi_slots);
return dm_new_connector_state->vcpi_slots;
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c
b/drivers/gpu/drm/drm_dp_mst_topology.c
index 74bed71f7315..bb0844dfb3d2 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -4020,6 +4020,7 @@ static int drm_dp_init_vcpi(struct
drm_dp_mst_topology_mgr *mgr,
* @mgr: MST topology manager for the port
* @port: port to find vcpi slots for
* @pbn: bandwidth required for the mode in PBN
+ * @pbn_div: divider for DSC mode that takes FEC into account
*
* Allocates VCPI slots to @port, replacing any previous VCPI allocations it
* may have had. Any atomic drivers which support MST must call this function
@@ -4046,7 +4047,8 @@ static int drm_dp_init_vcpi(struct
drm_dp_mst_topology_mgr *mgr,
*/
int drm_dp_atomic_find_vcpi_slots(struct drm_atomic_state *state,
struct drm_dp_mst_topology_mgr *mgr,
- struct drm_dp_mst_port *port, int pbn)
+ struct drm_dp_mst_port *port, int pbn,
+ int pbn_div)
{
struct drm_dp_mst_topology_state *topology_state;
struct drm_dp_vcpi_allocation *pos, *vcpi = NULL;
@@ -4079,7 +4081,10 @@ int drm_dp_atomic_find_vcpi_slots(struct
drm_atomic_state *state,
if (!vcpi)
prev_slots = 0;
- req_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
+ if (pbn_div <= 0)
+ pbn_div = mgr->pbn_div;
+
+ req_slots = DIV_ROUND_UP(pbn, pbn_div);
DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] [MST PORT:%p] VCPI %d -> %d\n",
port->connector->base.id, port->connector->name,
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c
b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index 92be17711287..a068f54a6793 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -65,7 +65,7 @@ static int intel_dp_mst_compute_link_config(struct
intel_encoder *encoder,
false);
slots = drm_dp_atomic_find_vcpi_slots(state, _dp->mst_mgr,
- port, crtc_state->pbn);
+ port, crtc_state->pbn, 0);
if (slots == -EDEADLK)
return slots;
if (slots >= 0)
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c
b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index 1c9e23d5a6fd..edb78966c5b6 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -787,7 +787,8 @@ nv50_msto_atomic_check(struct drm_encoder *encoder,
slots = drm_dp_atomic_find_vcpi_slots(state, >mgr,
mstc->port,
- asyh->dp.pbn);
+ asyh->dp.pbn,
+
