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1 Commits
| Author | SHA1 | Message | Date |
|---|---|---|---|
Gustavo Sousa
|
f14d81b710 |
drm/i915/cmtg: Disable the CMTG
The CMTG is a timing generator that runs in parallel with transcoders
timing generators and can be used as a reference for synchronization.
We have observed that we are inheriting from GOP a display configuration
with the CMTG enabled. Because our driver doesn't currently implement
any CMTG sequences, the CMTG ends up still enabled after our driver
takes over.
We need to make sure that the CMTG is not enabled if we are not going to
use it. For that, let's add a partial implementation in our driver that
only cares about disabling the CMTG if it was found enabled during
initial hardware readout. In the future, we can also implement sequences
for using the CMTG if that becomes a needed feature.
For now, we only deal with cases when it is possible to disable the CMTG
without requiring a modeset. For earlier display versions, we simply
skip if we find the CMTG enabled and we can't disable it without a
proper modeset. In the future, we need to properly handle that case.
v2:
- DG2 does not have the CMTG. Update HAS_CMTG() accordingly.
- Update logic to force disabling of CMTG only for initial commit.
v3:
- Add missing changes for v2 that were staged but not committed.
v4:
- Avoid if/else duplication in intel_cmtg_dump_state() by using "n/a"
for CMTG B enabled/disabled string for platforms without it. (Jani)
- Prefer intel_cmtg_readout_hw_state() over intel_cmtg_readout_state().
(Jani)
- Use display struct instead of i915 as first parameter for
TRANS_DDI_FUNC_CTL2(). (Jani)
- Fewer continuation lines in variable declaration/initialization for
better readability. (Jani)
- Coding style improvements. (Jani)
- Use drm_dbg_kms() instead of drm_info() for logging the disabling
of the CMTG.
- Make struct intel_cmtg_state entirely private to intel_cmtg.c.
v5:
- Do the disable sequence as part of the sanitization step after
hardware readout instead of initial modeset commit. (Jani)
- Adapt to commit
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