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Diffstat (limited to 'Documentation/gpu/drm-kms.rst')
| -rw-r--r-- | Documentation/gpu/drm-kms.rst | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/Documentation/gpu/drm-kms.rst b/Documentation/gpu/drm-kms.rst index c68588ce4090..b9330343d1bc 100644 --- a/Documentation/gpu/drm-kms.rst +++ b/Documentation/gpu/drm-kms.rst @@ -260,7 +260,8 @@ Taken all together there's two consequences for the atomic design: drm_connector_state <drm_connector_state>` for connectors. These are the only objects with userspace-visible and settable state. For internal state drivers can subclass these structures through embeddeding, or add entirely new state - structures for their globally shared hardware functions. + structures for their globally shared hardware functions, see :c:type:`struct + drm_private_state<drm_private_state>`. - An atomic update is assembled and validated as an entirely free-standing pile of structures within the :c:type:`drm_atomic_state <drm_atomic_state>` @@ -269,6 +270,14 @@ Taken all together there's two consequences for the atomic design: to the driver and modeset objects. This way rolling back an update boils down to releasing memory and unreferencing objects like framebuffers. +Locking of atomic state structures is internally using :c:type:`struct +drm_modeset_lock <drm_modeset_lock>`. As a general rule the locking shouldn't be +exposed to drivers, instead the right locks should be automatically acquired by +any function that duplicates or peeks into a state, like e.g. +:c:func:`drm_atomic_get_crtc_state()`. Locking only protects the software data +structure, ordering of committing state changes to hardware is sequenced using +:c:type:`struct drm_crtc_commit <drm_crtc_commit>`. + Read on in this chapter, and also in :ref:`drm_atomic_helper` for more detailed coverage of specific topics. |