| Message ID | 20170109133237.17413-4-tomeu.vizoso@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Jan 9, 2017 at 8:32 AM, Tomeu Vizoso <tomeu.vizoso@collabora.com> wrote: > Adds helpers for starting and stopping capture of frame CRCs through the > DPCD. When capture is on, a worker waits for vblanks and retrieves the > frame CRC to put it in the queue on the CRTC that is using the > eDP connector, so it's passed to userspace. > > v2: Reuse drm_crtc_wait_one_vblank > Update locking, as drm_crtc_add_crc_entry now takes the lock > > v3: Don't call wake_up_interruptible directly, that's now done in > drm_crtc_add_crc_entry. > > v4: Style fixes (Sean Paul) > Reworked retry of CRC reads (Sean Paul) > Flush worker after stopping CRC generationa (Sean Paul) > > Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> > --- > > drivers/gpu/drm/drm_dp_helper.c | 129 ++++++++++++++++++++++++++++++++++++++++ > include/drm/drm_dp_helper.h | 7 +++ > 2 files changed, 136 insertions(+) > > diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c > index 3e6fe82c6d64..f9018faf7e07 100644 > --- a/drivers/gpu/drm/drm_dp_helper.c > +++ b/drivers/gpu/drm/drm_dp_helper.c > @@ -981,6 +981,83 @@ static const struct i2c_lock_operations drm_dp_i2c_lock_ops = { > .unlock_bus = unlock_bus, > }; > > +static int drm_dp_aux_get_crc(struct drm_dp_aux *aux, u8 *crc) > +{ > + u8 buf, count; > + int ret; > + > + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK, &buf); > + if (ret < 0) > + return ret; > + > + WARN_ON(!(buf & DP_TEST_SINK_START)); > + > + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK_MISC, &buf); > + if (ret < 0) > + return ret; > + > + count = buf & DP_TEST_COUNT_MASK; > + if (count == aux->crc_count) > + return -EAGAIN; /* No CRC yet */ > + > + aux->crc_count = count; > + > + /* > + * At DP_TEST_CRC_R_CR, there's 6 bytes containing CRC data, 2 bytes > + * per component (RGB or CrYCb). > + */ > + ret = drm_dp_dpcd_read(aux, DP_TEST_CRC_R_CR, crc, 6); > + if (ret < 0) > + return ret; > + > + return 0; > +} > + > +static void drm_dp_aux_crc_work(struct work_struct *work) > +{ > + struct drm_dp_aux *aux = container_of(work, struct drm_dp_aux, > + crc_work); > + struct drm_crtc *crtc; > + u8 crc_bytes[6]; > + uint32_t crcs[3]; > + bool retry = false; > + int ret; > + > + if (WARN_ON(!aux->connector)) > + return; > + > + crtc = aux->connector->state->crtc; > + while (crtc->crc.opened) { > + if (!retry) { > + drm_crtc_wait_one_vblank(crtc); > + if (!crtc->crc.opened) > + break; > + } > + > + ret = drm_dp_aux_get_crc(aux, crc_bytes); > + if (ret == -EAGAIN) { > + if (retry) > + DRM_DEBUG_KMS("Failed to get a CRC even after retrying: %d\n", > + ret); > + retry = !retry; > + usleep_range(1000, 2000); > + continue; > + } > + > + retry = false; Yeah, the retry handling gets ugly fast, doesn't it? I think I'm coming around to your original way of handing things (with the addition of handling EAGAIN separately from other errors) Sean > + if (!ret) { > + crcs[0] = crc_bytes[0] | crc_bytes[1] << 8; > + crcs[1] = crc_bytes[2] | crc_bytes[3] << 8; > + crcs[2] = crc_bytes[4] | crc_bytes[5] << 8; > + ret = drm_crtc_add_crc_entry(crtc, false, 0, crcs); > + if (ret) > + DRM_DEBUG_KMS("Failed to add crc entry %d\n", ret); > + } else { > + DRM_DEBUG_KMS("Get CRC failed: %d\n", ret); > + } > + } > +} > + > /** > * drm_dp_aux_init() - minimally initialise an aux channel > * @aux: DisplayPort AUX channel > @@ -993,6 +1070,7 @@ static const struct i2c_lock_operations drm_dp_i2c_lock_ops = { > void drm_dp_aux_init(struct drm_dp_aux *aux) > { > mutex_init(&aux->hw_mutex); > + INIT_WORK(&aux->crc_work, drm_dp_aux_crc_work); > > aux->ddc.algo = &drm_dp_i2c_algo; > aux->ddc.algo_data = aux; > @@ -1081,3 +1159,54 @@ int drm_dp_psr_setup_time(const u8 psr_cap[EDP_PSR_RECEIVER_CAP_SIZE]) > EXPORT_SYMBOL(drm_dp_psr_setup_time); > > #undef PSR_SETUP_TIME > + > +/** > + * drm_dp_start_crc() - start capture of frame CRCs > + * @aux: DisplayPort AUX channel > + * > + * Returns 0 on success or a negative error code on failure. > + */ > +int drm_dp_start_crc(struct drm_dp_aux *aux) > +{ > + u8 buf; > + int ret; > + > + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK, &buf); > + if (ret < 0) > + return ret; > + > + ret = drm_dp_dpcd_writeb(aux, DP_TEST_SINK, buf | DP_TEST_SINK_START); > + if (ret < 0) > + return ret; > + > + aux->crc_count = 0; > + schedule_work(&aux->crc_work); > + > + return 0; > +} > +EXPORT_SYMBOL(drm_dp_start_crc); > + > +/** > + * drm_dp_stop_crc() - stop capture of frame CRCs > + * @aux: DisplayPort AUX channel > + * > + * Returns 0 on success or a negative error code on failure. > + */ > +int drm_dp_stop_crc(struct drm_dp_aux *aux) > +{ > + u8 buf; > + int ret; > + > + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK, &buf); > + if (ret < 0) > + return ret; > + > + ret = drm_dp_dpcd_writeb(aux, DP_TEST_SINK, buf & ~DP_TEST_SINK_START); > + if (ret < 0) > + return ret; > + > + flush_work(&aux->crc_work); > + > + return 0; > +} > +EXPORT_SYMBOL(drm_dp_stop_crc); > diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h > index 4fa77b434594..276e1ecd947b 100644 > --- a/include/drm/drm_dp_helper.h > +++ b/include/drm/drm_dp_helper.h > @@ -723,6 +723,8 @@ struct drm_dp_aux_msg { > * @dev: pointer to struct device that is the parent for this AUX channel > * @connector: backpointer to connector that uses this AUX channel > * @hw_mutex: internal mutex used for locking transfers > + * @crc_work: worker that captures CRCs for each frame > + * @crc_count: counter of captured frame CRCs > * @transfer: transfers a message representing a single AUX transaction > * > * The .dev field should be set to a pointer to the device that implements > @@ -760,6 +762,8 @@ struct drm_dp_aux { > struct device *dev; > struct drm_connector *connector; > struct mutex hw_mutex; > + struct work_struct crc_work; > + u8 crc_count; > ssize_t (*transfer)(struct drm_dp_aux *aux, > struct drm_dp_aux_msg *msg); > /** > @@ -838,4 +842,7 @@ void drm_dp_aux_init(struct drm_dp_aux *aux); > int drm_dp_aux_register(struct drm_dp_aux *aux); > void drm_dp_aux_unregister(struct drm_dp_aux *aux); > > +int drm_dp_start_crc(struct drm_dp_aux *aux); > +int drm_dp_stop_crc(struct drm_dp_aux *aux); > + > #endif /* _DRM_DP_HELPER_H_ */ > -- > 2.9.3 >
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 3e6fe82c6d64..f9018faf7e07 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -981,6 +981,83 @@ static const struct i2c_lock_operations drm_dp_i2c_lock_ops = { .unlock_bus = unlock_bus, }; +static int drm_dp_aux_get_crc(struct drm_dp_aux *aux, u8 *crc) +{ + u8 buf, count; + int ret; + + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK, &buf); + if (ret < 0) + return ret; + + WARN_ON(!(buf & DP_TEST_SINK_START)); + + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK_MISC, &buf); + if (ret < 0) + return ret; + + count = buf & DP_TEST_COUNT_MASK; + if (count == aux->crc_count) + return -EAGAIN; /* No CRC yet */ + + aux->crc_count = count; + + /* + * At DP_TEST_CRC_R_CR, there's 6 bytes containing CRC data, 2 bytes + * per component (RGB or CrYCb). + */ + ret = drm_dp_dpcd_read(aux, DP_TEST_CRC_R_CR, crc, 6); + if (ret < 0) + return ret; + + return 0; +} + +static void drm_dp_aux_crc_work(struct work_struct *work) +{ + struct drm_dp_aux *aux = container_of(work, struct drm_dp_aux, + crc_work); + struct drm_crtc *crtc; + u8 crc_bytes[6]; + uint32_t crcs[3]; + bool retry = false; + int ret; + + if (WARN_ON(!aux->connector)) + return; + + crtc = aux->connector->state->crtc; + while (crtc->crc.opened) { + if (!retry) { + drm_crtc_wait_one_vblank(crtc); + if (!crtc->crc.opened) + break; + } + + ret = drm_dp_aux_get_crc(aux, crc_bytes); + if (ret == -EAGAIN) { + if (retry) + DRM_DEBUG_KMS("Failed to get a CRC even after retrying: %d\n", + ret); + retry = !retry; + usleep_range(1000, 2000); + continue; + } + + retry = false; + if (!ret) { + crcs[0] = crc_bytes[0] | crc_bytes[1] << 8; + crcs[1] = crc_bytes[2] | crc_bytes[3] << 8; + crcs[2] = crc_bytes[4] | crc_bytes[5] << 8; + ret = drm_crtc_add_crc_entry(crtc, false, 0, crcs); + if (ret) + DRM_DEBUG_KMS("Failed to add crc entry %d\n", ret); + } else { + DRM_DEBUG_KMS("Get CRC failed: %d\n", ret); + } + } +} + /** * drm_dp_aux_init() - minimally initialise an aux channel * @aux: DisplayPort AUX channel @@ -993,6 +1070,7 @@ static const struct i2c_lock_operations drm_dp_i2c_lock_ops = { void drm_dp_aux_init(struct drm_dp_aux *aux) { mutex_init(&aux->hw_mutex); + INIT_WORK(&aux->crc_work, drm_dp_aux_crc_work); aux->ddc.algo = &drm_dp_i2c_algo; aux->ddc.algo_data = aux; @@ -1081,3 +1159,54 @@ int drm_dp_psr_setup_time(const u8 psr_cap[EDP_PSR_RECEIVER_CAP_SIZE]) EXPORT_SYMBOL(drm_dp_psr_setup_time); #undef PSR_SETUP_TIME + +/** + * drm_dp_start_crc() - start capture of frame CRCs + * @aux: DisplayPort AUX channel + * + * Returns 0 on success or a negative error code on failure. + */ +int drm_dp_start_crc(struct drm_dp_aux *aux) +{ + u8 buf; + int ret; + + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK, &buf); + if (ret < 0) + return ret; + + ret = drm_dp_dpcd_writeb(aux, DP_TEST_SINK, buf | DP_TEST_SINK_START); + if (ret < 0) + return ret; + + aux->crc_count = 0; + schedule_work(&aux->crc_work); + + return 0; +} +EXPORT_SYMBOL(drm_dp_start_crc); + +/** + * drm_dp_stop_crc() - stop capture of frame CRCs + * @aux: DisplayPort AUX channel + * + * Returns 0 on success or a negative error code on failure. + */ +int drm_dp_stop_crc(struct drm_dp_aux *aux) +{ + u8 buf; + int ret; + + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK, &buf); + if (ret < 0) + return ret; + + ret = drm_dp_dpcd_writeb(aux, DP_TEST_SINK, buf & ~DP_TEST_SINK_START); + if (ret < 0) + return ret; + + flush_work(&aux->crc_work); + + return 0; +} +EXPORT_SYMBOL(drm_dp_stop_crc); diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 4fa77b434594..276e1ecd947b 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -723,6 +723,8 @@ struct drm_dp_aux_msg { * @dev: pointer to struct device that is the parent for this AUX channel * @connector: backpointer to connector that uses this AUX channel * @hw_mutex: internal mutex used for locking transfers + * @crc_work: worker that captures CRCs for each frame + * @crc_count: counter of captured frame CRCs * @transfer: transfers a message representing a single AUX transaction * * The .dev field should be set to a pointer to the device that implements @@ -760,6 +762,8 @@ struct drm_dp_aux { struct device *dev; struct drm_connector *connector; struct mutex hw_mutex; + struct work_struct crc_work; + u8 crc_count; ssize_t (*transfer)(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg); /** @@ -838,4 +842,7 @@ void drm_dp_aux_init(struct drm_dp_aux *aux); int drm_dp_aux_register(struct drm_dp_aux *aux); void drm_dp_aux_unregister(struct drm_dp_aux *aux); +int drm_dp_start_crc(struct drm_dp_aux *aux); +int drm_dp_stop_crc(struct drm_dp_aux *aux); + #endif /* _DRM_DP_HELPER_H_ */
Adds helpers for starting and stopping capture of frame CRCs through the DPCD. When capture is on, a worker waits for vblanks and retrieves the frame CRC to put it in the queue on the CRTC that is using the eDP connector, so it's passed to userspace. v2: Reuse drm_crtc_wait_one_vblank Update locking, as drm_crtc_add_crc_entry now takes the lock v3: Don't call wake_up_interruptible directly, that's now done in drm_crtc_add_crc_entry. v4: Style fixes (Sean Paul) Reworked retry of CRC reads (Sean Paul) Flush worker after stopping CRC generationa (Sean Paul) Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> --- drivers/gpu/drm/drm_dp_helper.c | 129 ++++++++++++++++++++++++++++++++++++++++ include/drm/drm_dp_helper.h | 7 +++ 2 files changed, 136 insertions(+)