From: Tomasz Figa tfiga@chromium.org

Currently both rockchip_drm_psr_activate() and _deactivate() only set the boolean "active" flag without actually making sure that hardware state complies with it.

Since we are going to extend the usage of this API to properly lock PSR for the duration of atomic commits, we change the semantics in following way: - a counter is used to track the number of disallow requests, - PSR is actually disabled in hardware on first disallow request, - PSR enable work is scheduled on last disallow request.

The above allows using the API as a way to deterministically synchronize PSR state changes with other DRM events, i.e. atomic commits and cursor updates. As a nice side effect, the naming is sorted out and we have "inhibit" for stopping the software logic and "enable" for hardware state.

Signed-off-by: Tomasz Figa tfiga@chromium.org Signed-off-by: Thierry Escande thierry.escande@collabora.com Signed-off-by: Enric Balletbo i Serra enric.balletbo@collabora.com ---

drivers/gpu/drm/rockchip/analogix_dp-rockchip.c | 4 +- drivers/gpu/drm/rockchip/rockchip_drm_psr.c | 57 ++++++++++++++++++------- drivers/gpu/drm/rockchip/rockchip_drm_psr.h | 4 +- 3 files changed, 46 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c index 6d45d62466b3..080f05352195 100644 --- a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c +++ b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c @@ -134,7 +134,7 @@ static int rockchip_dp_poweron_end(struct analogix_dp_plat_data *plat_data) { struct rockchip_dp_device *dp = to_dp(plat_data);

- return rockchip_drm_psr_activate(&dp->encoder); + return rockchip_drm_psr_inhibit_put(&dp->encoder); }

static int rockchip_dp_powerdown(struct analogix_dp_plat_data *plat_data) @@ -142,7 +142,7 @@ static int rockchip_dp_powerdown(struct analogix_dp_plat_data *plat_data) struct rockchip_dp_device *dp = to_dp(plat_data); int ret;

- ret = rockchip_drm_psr_deactivate(&dp->encoder); + ret = rockchip_drm_psr_inhibit_get(&dp->encoder); if (ret != 0) return ret;

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_psr.c b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c index 448c5fde241c..e7e16d92d5a1 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_psr.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c @@ -27,7 +27,7 @@ struct psr_drv { struct drm_encoder *encoder;

struct mutex lock; - bool active; + int inhibit_count; bool enabled;

struct delayed_work flush_work; @@ -76,7 +76,7 @@ static int psr_set_state_locked(struct psr_drv *psr, bool enable) { int ret;

- if (!psr->active) + if (psr->inhibit_count > 0) return -EINVAL;

if (enable == psr->enabled) @@ -101,13 +101,18 @@ static void psr_flush_handler(struct work_struct *work) }

/** - * rockchip_drm_psr_activate - activate PSR on the given pipe + * rockchip_drm_psr_inhibit_put - release PSR inhibit on given encoder * @encoder: encoder to obtain the PSR encoder * + * Decrements PSR inhibit count on given encoder. Should be called only + * for a PSR inhibit count increment done before. If PSR inhibit counter + * reaches zero, PSR flush work is scheduled to make the hardware enter + * PSR mode in PSR_FLUSH_TIMEOUT_MS. + * * Returns: * Zero on success, negative errno on failure. */ -int rockchip_drm_psr_activate(struct drm_encoder *encoder) +int rockchip_drm_psr_inhibit_put(struct drm_encoder *encoder) { struct psr_drv *psr = find_psr_by_encoder(encoder);

@@ -115,21 +120,29 @@ int rockchip_drm_psr_activate(struct drm_encoder *encoder) return PTR_ERR(psr);

mutex_lock(&psr->lock); - psr->active = true; + --psr->inhibit_count; + if (!psr->inhibit_count) + mod_delayed_work(system_wq, &psr->flush_work, + PSR_FLUSH_TIMEOUT_MS); mutex_unlock(&psr->lock);

return 0; } -EXPORT_SYMBOL(rockchip_drm_psr_activate); +EXPORT_SYMBOL(rockchip_drm_psr_inhibit_put);

/** - * rockchip_drm_psr_deactivate - deactivate PSR on the given pipe + * rockchip_drm_psr_inhibit_get - acquire PSR inhibit on given encoder * @encoder: encoder to obtain the PSR encoder * + * Increments PSR inhibit count on given encoder. This function guarantees + * that after it returns PSR is turned off on given encoder and no PSR-related + * hardware state change occurs at least until a matching call to + * rockchip_drm_psr_inhibit_put() is done. + * * Returns: * Zero on success, negative errno on failure. */ -int rockchip_drm_psr_deactivate(struct drm_encoder *encoder) +int rockchip_drm_psr_inhibit_get(struct drm_encoder *encoder) { struct psr_drv *psr = find_psr_by_encoder(encoder);

@@ -137,15 +150,15 @@ int rockchip_drm_psr_deactivate(struct drm_encoder *encoder) return PTR_ERR(psr);

mutex_lock(&psr->lock); - psr->active = false; - psr->enabled = false; + psr_set_state_locked(psr, false); + ++psr->inhibit_count; mutex_unlock(&psr->lock); cancel_delayed_work_sync(&psr->flush_work); cancel_work_sync(&psr->disable_work);

return 0; } -EXPORT_SYMBOL(rockchip_drm_psr_deactivate); +EXPORT_SYMBOL(rockchip_drm_psr_inhibit_get);

static void rockchip_drm_do_flush(struct psr_drv *psr) { @@ -301,6 +314,11 @@ static const struct input_device_id psr_ids[] = { * @encoder: encoder that obtain the PSR function * @psr_set: call back to set PSR state * + * The function returns with PSR inhibit counter initialized with one + * and the caller (typically encoder driver) needs to call + * rockchip_drm_psr_inhibit_put() when it becomes ready to accept PSR + * enable request. + * * Returns: * Zero on success, negative errno on failure. */ @@ -322,7 +340,7 @@ int rockchip_drm_psr_register(struct drm_encoder *encoder, INIT_WORK(&psr->disable_work, psr_disable_handler); mutex_init(&psr->lock);

- psr->active = false; + psr->inhibit_count = 1; psr->enabled = false; psr->encoder = encoder; psr->set = psr_set; @@ -362,6 +380,11 @@ EXPORT_SYMBOL(rockchip_drm_psr_register); * @encoder: encoder that obtain the PSR function * @psr_set: call back to set PSR state * + * It is expected that the PSR inhibit counter is 1 when this function is + * called, which corresponds to a state when related encoder has been + * disconnected from any CRTCs and its driver called + * rockchip_drm_psr_inhibit_get() to stop the PSR logic. + * * Returns: * Zero on success, negative errno on failure. */ @@ -373,10 +396,14 @@ void rockchip_drm_psr_unregister(struct drm_encoder *encoder) mutex_lock(&drm_drv->psr_list_lock); list_for_each_entry_safe(psr, n, &drm_drv->psr_list, list) { if (psr->encoder == encoder) { - input_unregister_handler(&psr->input_handler); - cancel_delayed_work_sync(&psr->flush_work); - cancel_work_sync(&psr->disable_work); + /* + * Any other value would mean that the encoder + * is still in use. + */ + WARN_ON(psr->inhibit_count != 1); + list_del(&psr->list); + input_unregister_handler(&psr->input_handler); kfree(psr->input_handler.name); kfree(psr); } diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_psr.h b/drivers/gpu/drm/rockchip/rockchip_drm_psr.h index 06537ee27565..40e026c14168 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_psr.h +++ b/drivers/gpu/drm/rockchip/rockchip_drm_psr.h @@ -18,8 +18,8 @@ void rockchip_drm_psr_flush_all(struct drm_device *dev); int rockchip_drm_psr_flush(struct drm_crtc *crtc);

-int rockchip_drm_psr_activate(struct drm_encoder *encoder); -int rockchip_drm_psr_deactivate(struct drm_encoder *encoder); +int rockchip_drm_psr_inhibit_put(struct drm_encoder *encoder); +int rockchip_drm_psr_inhibit_get(struct drm_encoder *encoder);

int rockchip_drm_psr_register(struct drm_encoder *encoder, int (*psr_set)(struct drm_encoder *, bool enable));

From: Tomasz Figa tfiga@chromium.org

Currently PSR flush is triggered from CRTC's .atomic_begin() callback, which is executed after modeset disables and enables and before plane updates are committed. Since PSR flush and re-enable can be triggered asynchronously by external sources (input event, delayed work), it can race with hardware programming done in the aforementioned stages.

This patch blocks the PSR completely before hardware programming part begins and unblock after it ends. This relies on reference counted PSR disable introduced with previous patch.

Cc: Kristian H. Kristensen hoegsberg@chromium.org Signed-off-by: Tomasz Figa tfiga@chromium.org Signed-off-by: Sean Paul seanpaul@chromium.org Signed-off-by: Thierry Escande thierry.escande@collabora.com Signed-off-by: Enric Balletbo i Serra enric.balletbo@collabora.com ---

drivers/gpu/drm/rockchip/rockchip_drm_fb.c | 61 ++++++++++++++++++++++++++++- drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 7 ---- 2 files changed, 60 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_fb.c b/drivers/gpu/drm/rockchip/rockchip_drm_fb.c index e266539e04e5..d4f4118b482d 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_fb.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_fb.c @@ -167,8 +167,67 @@ rockchip_user_fb_create(struct drm_device *dev, struct drm_file *file_priv, return ERR_PTR(ret); }

+static void +rockchip_drm_psr_inhibit_get_state(struct drm_atomic_state *state) +{ + struct drm_crtc *crtc; + struct drm_crtc_state *crtc_state; + struct drm_encoder *encoder; + u32 encoder_mask = 0; + int i; + + for_each_old_crtc_in_state(state, crtc, crtc_state, i) { + encoder_mask |= crtc_state->encoder_mask; + encoder_mask |= crtc->state->encoder_mask; + } + + drm_for_each_encoder_mask(encoder, state->dev, encoder_mask) + rockchip_drm_psr_inhibit_get(encoder); +} + +static void +rockchip_drm_psr_inhibit_put_state(struct drm_atomic_state *state) +{ + struct drm_crtc *crtc; + struct drm_crtc_state *crtc_state; + struct drm_encoder *encoder; + u32 encoder_mask = 0; + int i; + + for_each_old_crtc_in_state(state, crtc, crtc_state, i) { + encoder_mask |= crtc_state->encoder_mask; + encoder_mask |= crtc->state->encoder_mask; + } + + drm_for_each_encoder_mask(encoder, state->dev, encoder_mask) + rockchip_drm_psr_inhibit_put(encoder); +} + +static void +rockchip_atomic_helper_commit_tail_rpm(struct drm_atomic_state *old_state) +{ + struct drm_device *dev = old_state->dev; + + rockchip_drm_psr_inhibit_get_state(old_state); + + drm_atomic_helper_commit_modeset_disables(dev, old_state); + + drm_atomic_helper_commit_modeset_enables(dev, old_state); + + drm_atomic_helper_commit_planes(dev, old_state, + DRM_PLANE_COMMIT_ACTIVE_ONLY); + + rockchip_drm_psr_inhibit_put_state(old_state); + + drm_atomic_helper_commit_hw_done(old_state); + + drm_atomic_helper_wait_for_vblanks(dev, old_state); + + drm_atomic_helper_cleanup_planes(dev, old_state); +} + static const struct drm_mode_config_helper_funcs rockchip_mode_config_helpers = { - .atomic_commit_tail = drm_atomic_helper_commit_tail_rpm, + .atomic_commit_tail = rockchip_atomic_helper_commit_tail_rpm, };

static const struct drm_mode_config_funcs rockchip_drm_mode_config_funcs = { diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c index 42562ab04bde..12ebaec740c6 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -1032,16 +1032,9 @@ static void vop_crtc_atomic_flush(struct drm_crtc *crtc, } }

-static void vop_crtc_atomic_begin(struct drm_crtc *crtc, - struct drm_crtc_state *old_crtc_state) -{ - rockchip_drm_psr_flush(crtc); -} - static const struct drm_crtc_helper_funcs vop_crtc_helper_funcs = { .mode_fixup = vop_crtc_mode_fixup, .atomic_flush = vop_crtc_atomic_flush, - .atomic_begin = vop_crtc_atomic_begin, .atomic_enable = vop_crtc_atomic_enable, .atomic_disable = vop_crtc_atomic_disable, };