The return from the call to _mixer_stages can be a negative error
code however this is being assigned to an unsigned variable 'stages'
hence the check is always false. Fix this by making 'stages' an
int.
Detected by Coccinelle ("Unsigned expression compared with zero:
stages < 0")
Fixes: 25fdd5933e ("drm/msm: Add SDM845 DPU support")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Rob Clark <robdclark@gmail.com>
Support for CDM block is not present in DPU. Remove CDM
handlers from resource manager.
changes in v4:
- Introduced in the series
changes in v5:
- Remove catalog references to CDM (Sean)
Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
SDM845 SoC includes the Mobile Display Sub System (MDSS) which is a
top level wrapper consisting of Display Processing Unit (DPU) and
display peripheral modules such as Display Serial Interface (DSI)
and DisplayPort (DP).
MDSS functions essentially as a back-end composition engine. It blends
video and graphic images stored in the frame buffers and scans out the
composed image to a display sink (over DSI/DP).
The following diagram represents hardware blocks for a simple pipeline
(two planes are present on a given crtc which is connected to a DSI
connector):
MDSS
+---------------------------------+
| +-----------------------------+ |
| | DPU | |
| | +--------+ +--------+ | |
| | | SSPP | | SSPP | | |
| | +----+---+ +----+---+ | |
| | | | | |
| | +----v-----------v---+ | |
| | | Layer Mixer (LM) | | |
| | +--------------------+ | |
| | +--------------------+ | |
| | | PingPong (PP) | | |
| | +--------------------+ | |
| | +--------------------+ | |
| | | INTERFACE (VIDEO) | | |
| | +---+----------------+ | |
| +------|----------------------+ |
| | |
| +------|---------------------+ |
| | | DISPLAY PERIPHERALS | |
| | +---v-+ +-----+ | |
| | | DSI | | DP | | |
| | +-----+ +-----+ | |
| +----------------------------+ |
+---------------------------------+
The number of DPU sub-blocks (i.e. SSPPs, LMs, PP blocks and INTFs)
depends on SoC capabilities.
Overview of DPU sub-blocks:
---------------------------
* Source Surface Processor (SSPP):
Refers to any of hardware pipes like ViG, DMA etc. Only ViG pipes are
capable of performing format conversion, scaling and quality improvement
for source surfaces.
* Layer Mixer (LM):
Blend source surfaces together (in requested zorder)
* PingPong (PP):
This block controls frame done interrupt output, EOL and EOF generation,
overflow/underflow control.
* Display interface (INTF):
Timing generator and interface connecting the display peripherals.
DRM components mapping to DPU architecture:
------------------------------------------
PLANEs maps to SSPPs
CRTC maps to LMs
Encoder maps to PPs, INTFs
Data flow setup:
---------------
MDSS hardware can support various data flows (e.g.):
- Dual pipe: Output from two LMs combined to single display.
- Split display: Output from two LMs connected to two separate
interfaces.
The hardware capabilities determine the number of concurrent data paths
possible. Any control path (i.e. pipeline w/i DPU) can be routed to any
of the hardware data paths. A given control path can be triggered,
flushed and controlled independently.
Changes in v3:
- Move msm_media_info.h from uapi to dpu/ subdir
- Remove preclose callback dpu (it's handled in core)
- Fix kbuild warnings with parent_ops
- Remove unused functions from dpu_core_irq
- Rename mdss_phys to mdss
- Rename mdp_phys address space to mdp
- Drop _phys from vbif and regdma binding names
Signed-off-by: Abhinav Kumar <abhinavk@codeaurora.org>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Chandan Uddaraju <chandanu@codeaurora.org>
Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rajesh Yadav <ryadav@codeaurora.org>
Signed-off-by: Sravanthi Kollukuduru <skolluku@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
[robclark minor rebase]
Signed-off-by: Rob Clark <robdclark@gmail.com>
