diff options
author | Yakir Yang <ykk@rock-chips.com> | 2016-07-24 09:57:44 +0300 |
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committer | Sean Paul <seanpaul@chromium.org> | 2016-08-23 18:44:32 +0300 |
commit | 5182c1a556d7ff70e28516c4b9250a347b732af0 (patch) | |
tree | 60c2d74532993ab5f9623a43ce93d50c05044adf /drivers/gpu/drm/rockchip/rockchip_drm_psr.c | |
parent | 69c34e41f5d4e8a719d67673647b39f807ae8c71 (diff) | |
download | linux-5182c1a556d7ff70e28516c4b9250a347b732af0.tar.xz |
drm/rockchip: add an common abstracted PSR driver
The PSR driver have exported four symbols for specific device driver, and
it's safe to call them in interrupt context:
- rockchip_drm_psr_register()
- rockchip_drm_psr_unregister()
- rockchip_drm_psr_enable()
- rockchip_drm_psr_disable()
- rockchip_drm_psr_flush()
Encoder driver should call the register/unregister interfaces to hook
itself into common PSR driver, encoder have implement the 'psr_set'
callback which use the set PSR state in hardware side.
Crtc driver would call the enable/disable interfaces when vblank is
enable/disable, after that the common PSR driver would call the encoder
registered callback to set the PSR state.
Fb driver would call the flush interface in 'fb->dirty' callback, this
helper function would force all PSR enabled encoders to exit from PSR
for 3 seconds.
Signed-off-by: Yakir Yang <ykk@rock-chips.com>
[seanpaul removed leftover psr_enabled/psr_work kruft from drm_vop.c]
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Diffstat (limited to 'drivers/gpu/drm/rockchip/rockchip_drm_psr.c')
-rw-r--r-- | drivers/gpu/drm/rockchip/rockchip_drm_psr.c | 249 |
1 files changed, 249 insertions, 0 deletions
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_psr.c b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c new file mode 100644 index 000000000000..a6d3bd25b905 --- /dev/null +++ b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c @@ -0,0 +1,249 @@ +/* + * Copyright (C) Fuzhou Rockchip Electronics Co.Ltd + * Author: Yakir Yang <ykk@rock-chips.com> + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <drm/drmP.h> +#include <drm/drm_crtc_helper.h> + +#include "rockchip_drm_drv.h" +#include "rockchip_drm_psr.h" + +#define PSR_FLUSH_TIMEOUT msecs_to_jiffies(3000) /* 3 seconds */ +#define PSR_SET_DELAY_TIME msecs_to_jiffies(10) + +enum psr_state { + PSR_FLUSH, + PSR_ENABLE, + PSR_DISABLE, +}; + +struct psr_drv { + struct list_head list; + struct drm_encoder *encoder; + + enum psr_state request_state; + enum psr_state state; + + struct delayed_work state_work; + + struct timer_list flush_timer; + + void (*set)(struct drm_encoder *encoder, bool enable); +}; + +static struct psr_drv *find_psr_by_crtc(struct drm_crtc *crtc) +{ + struct rockchip_drm_private *drm_drv = crtc->dev->dev_private; + struct psr_drv *psr; + + list_for_each_entry(psr, &drm_drv->psr_list, list) + if (psr->encoder->crtc == crtc) + return psr; + + return ERR_PTR(-ENODEV); +} + +static void psr_state_work(struct work_struct *work) +{ + struct psr_drv *psr = container_of(work, typeof(*psr), state_work.work); + enum psr_state request_state = psr->request_state; + + /* + * Allowed finite state machine: + * + * PSR_ENABLE < = = = = = > PSR_FLUSH + * | ^ | + * | | | + * v | | + * PSR_DISABLE < - - - - - - - - - + */ + + /* Forbid no state change */ + if (request_state == psr->state) + return; + + /* Forbid DISABLE change to FLUSH */ + if (request_state == PSR_FLUSH && psr->state == PSR_DISABLE) + return; + + /* Allow but no need hardware change, just need assign the state */ + if (request_state == PSR_DISABLE && psr->state == PSR_FLUSH) { + psr->state = request_state; + return; + } + + /* Only wrote in this work, no need lock protection */ + psr->state = request_state; + + /* Refact to hardware state change */ + switch (request_state) { + case PSR_ENABLE: + psr->set(psr->encoder, true); + break; + + case PSR_DISABLE: + case PSR_FLUSH: + psr->set(psr->encoder, false); + break; + } +} + +static void psr_set_state(struct psr_drv *psr, enum psr_state state) +{ + psr->request_state = state; + + schedule_delayed_work(&psr->state_work, PSR_SET_DELAY_TIME); +} + +static void psr_flush_handler(unsigned long data) +{ + struct psr_drv *psr = (struct psr_drv *)data; + + if (!psr) + return; + + /* State changed between flush time, then keep it */ + if (psr->request_state != PSR_FLUSH) + return; + + psr_set_state(psr, PSR_ENABLE); +} + +/** + * rockchip_drm_psr_enable - enable the encoder PSR which bind to given CRTC + * @crtc: CRTC to obtain the PSR encoder + * + * Returns: + * Zero on success, negative errno on failure. + */ +int rockchip_drm_psr_enable(struct drm_crtc *crtc) +{ + struct psr_drv *psr = find_psr_by_crtc(crtc); + + if (IS_ERR(psr)) + return PTR_ERR(psr); + + psr_set_state(psr, PSR_ENABLE); + return 0; +} +EXPORT_SYMBOL(rockchip_drm_psr_enable); + +/** + * rockchip_drm_psr_disable - disable the encoder PSR which bind to given CRTC + * @crtc: CRTC to obtain the PSR encoder + * + * Returns: + * Zero on success, negative errno on failure. + */ +int rockchip_drm_psr_disable(struct drm_crtc *crtc) +{ + struct psr_drv *psr = find_psr_by_crtc(crtc); + + if (IS_ERR(psr)) + return PTR_ERR(psr); + + psr_set_state(psr, PSR_DISABLE); + return 0; +} +EXPORT_SYMBOL(rockchip_drm_psr_disable); + +/** + * rockchip_drm_psr_flush - force to flush all registered PSR encoders + * @dev: drm device + * + * Disable the PSR function for all registered encoders, and then enable the + * PSR function back after PSR_FLUSH_TIMEOUT. If encoder PSR state have been + * changed during flush time, then keep the state no change after flush + * timeout. + * + * Returns: + * Zero on success, negative errno on failure. + */ +void rockchip_drm_psr_flush(struct drm_device *dev) +{ + struct rockchip_drm_private *drm_drv = dev->dev_private; + struct psr_drv *psr; + + list_for_each_entry(psr, &drm_drv->psr_list, list) { + if (psr->request_state == PSR_DISABLE) + continue; + + mod_timer(&psr->flush_timer, + round_jiffies_up(jiffies + PSR_FLUSH_TIMEOUT)); + + psr_set_state(psr, PSR_FLUSH); + } +} +EXPORT_SYMBOL(rockchip_drm_psr_flush); + +/** + * rockchip_drm_psr_register - register encoder to psr driver + * @encoder: encoder that obtain the PSR function + * @psr_set: call back to set PSR state + * + * Returns: + * Zero on success, negative errno on failure. + */ +int rockchip_drm_psr_register(struct drm_encoder *encoder, + void (*psr_set)(struct drm_encoder *, bool enable)) +{ + struct rockchip_drm_private *drm_drv = encoder->dev->dev_private; + struct psr_drv *psr; + + if (!encoder || !psr_set) + return -EINVAL; + + psr = kzalloc(sizeof(struct psr_drv), GFP_KERNEL); + if (!psr) + return -ENOMEM; + + setup_timer(&psr->flush_timer, psr_flush_handler, (unsigned long)psr); + + INIT_DELAYED_WORK(&psr->state_work, psr_state_work); + + psr->state = PSR_DISABLE; + psr->encoder = encoder; + psr->set = psr_set; + + mutex_lock(&drm_drv->psr_list_mutex); + list_add_tail(&psr->list, &drm_drv->psr_list); + mutex_unlock(&drm_drv->psr_list_mutex); + + return 0; +} +EXPORT_SYMBOL(rockchip_drm_psr_register); + +/** + * rockchip_drm_psr_unregister - unregister encoder to psr driver + * @encoder: encoder that obtain the PSR function + * @psr_set: call back to set PSR state + * + * Returns: + * Zero on success, negative errno on failure. + */ +void rockchip_drm_psr_unregister(struct drm_encoder *encoder) +{ + struct rockchip_drm_private *drm_drv = encoder->dev->dev_private; + struct psr_drv *psr, *n; + + mutex_lock(&drm_drv->psr_list_mutex); + list_for_each_entry_safe(psr, n, &drm_drv->psr_list, list) { + if (psr->encoder == encoder) { + del_timer(&psr->flush_timer); + list_del(&psr->list); + kfree(psr); + } + } + mutex_unlock(&drm_drv->psr_list_mutex); +} +EXPORT_SYMBOL(rockchip_drm_psr_unregister); |