From: Tomasz Figa tfiga@chromium.org
The first time after we call rockchip_drm_do_flush() after rockchip_drm_psr_register(), we go from PSR_DISABLE to PSR_FLUSH. The difference between PSR_DISABLE and PSR_FLUSH is whether or not we have a delayed work pending - PSR is off in either state. However psr_set_state() only catches the transition from PSR_FLUSH to PSR_DISABLE (which never happens), while going from PSR_DISABLE to PSR_FLUSH triggers a call to psr->set() to disable PSR while it's already disabled. This triggers the eDP PHY power-on sequence without being shut down first and this seems to occasionally leave the encoder unable to later enable PSR. Let's just simplify the state machine and simply consider PSR_DISABLE and PSR_FLUSH the same state. This lets us represent the hardware state by a simple boolean called "enabled" and, while at it, rename the misleading "active" boolean to "inhibit", which represents the purpose much better.
Also, userspace can (and does) trigger the rockchip_drm_do_flush() path from drmModeDirtyFB() at any time, whether or the encoder is active. If no mode is set, we call into analogix_dp_psr_set() which returns -EINVAL because encoder->crtc is NULL. Avoid this by starting out with psr->allowed set to false.
Signed-off-by: Kristian H. Kristensen hoegsberg@chromium.org Signed-off-by: Tomasz Figa tfiga@chromium.org Signed-off-by: Thierry Escande thierry.escande@collabora.com --- drivers/gpu/drm/rockchip/rockchip_drm_psr.c | 79 +++++++++-------------------- 1 file changed, 23 insertions(+), 56 deletions(-)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_psr.c b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c index c8655e625ba2..448c5fde241c 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_psr.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c @@ -22,19 +22,13 @@
#define PSR_FLUSH_TIMEOUT_MS 100
-enum psr_state { - PSR_FLUSH, - PSR_ENABLE, - PSR_DISABLE, -}; - struct psr_drv { struct list_head list; struct drm_encoder *encoder;
struct mutex lock; bool active; - enum psr_state state; + bool enabled;
struct delayed_work flush_work; struct work_struct disable_work; @@ -78,52 +72,22 @@ static struct psr_drv *find_psr_by_encoder(struct drm_encoder *encoder) return psr; }
-static void psr_set_state_locked(struct psr_drv *psr, enum psr_state state) +static int psr_set_state_locked(struct psr_drv *psr, bool enable) { - /* - * Allowed finite state machine: - * - * PSR_ENABLE < = = = = = > PSR_FLUSH - * | ^ | - * | | | - * v | | - * PSR_DISABLE < - - - - - - - - - - */ - if (state == psr->state || !psr->active) - return; - - /* Already disabled in flush, change the state, but not the hardware */ - if (state == PSR_DISABLE && psr->state == PSR_FLUSH) { - psr->state = state; - return; - } + int ret;
- /* Actually commit the state change to hardware */ - switch (state) { - case PSR_ENABLE: - if (psr->set(psr->encoder, true)) - return; - break; - - case PSR_DISABLE: - case PSR_FLUSH: - if (psr->set(psr->encoder, false)) - return; - break; - - default: - pr_err("%s: Unknown state %d\n", __func__, state); - return; - } + if (!psr->active) + return -EINVAL;
- psr->state = state; -} + if (enable == psr->enabled) + return 0;
-static void psr_set_state(struct psr_drv *psr, enum psr_state state) -{ - mutex_lock(&psr->lock); - psr_set_state_locked(psr, state); - mutex_unlock(&psr->lock); + ret = psr->set(psr->encoder, enable); + if (ret) + return ret; + + psr->enabled = enable; + return 0; }
static void psr_flush_handler(struct work_struct *work) @@ -131,10 +95,8 @@ static void psr_flush_handler(struct work_struct *work) struct psr_drv *psr = container_of(to_delayed_work(work), struct psr_drv, flush_work);
- /* If the state has changed since we initiated the flush, do nothing */ mutex_lock(&psr->lock); - if (psr->state == PSR_FLUSH) - psr_set_state_locked(psr, PSR_ENABLE); + psr_set_state_locked(psr, true); mutex_unlock(&psr->lock); }
@@ -176,6 +138,7 @@ int rockchip_drm_psr_deactivate(struct drm_encoder *encoder)
mutex_lock(&psr->lock); psr->active = false; + psr->enabled = false; mutex_unlock(&psr->lock); cancel_delayed_work_sync(&psr->flush_work); cancel_work_sync(&psr->disable_work); @@ -187,8 +150,12 @@ EXPORT_SYMBOL(rockchip_drm_psr_deactivate); static void rockchip_drm_do_flush(struct psr_drv *psr) { cancel_delayed_work_sync(&psr->flush_work); - psr_set_state(psr, PSR_FLUSH); - mod_delayed_work(system_wq, &psr->flush_work, PSR_FLUSH_TIMEOUT_MS); + + mutex_lock(&psr->lock); + if (!psr_set_state_locked(psr, false)) + mod_delayed_work(system_wq, &psr->flush_work, + PSR_FLUSH_TIMEOUT_MS); + mutex_unlock(&psr->lock); }
/** @@ -355,8 +322,8 @@ int rockchip_drm_psr_register(struct drm_encoder *encoder, INIT_WORK(&psr->disable_work, psr_disable_handler); mutex_init(&psr->lock);
- psr->active = true; - psr->state = PSR_DISABLE; + psr->active = false; + psr->enabled = false; psr->encoder = encoder; psr->set = psr_set;