Hi, On 2016ë 06ì 06ì¼ 19:13, Lin Huang wrote: > when in ddr frequency scaling process, vop can not do > enable or disable operate, since dcf will base on vop vblank > time to do frequency scaling and need to get vop irq if there > have vop enabled. So need register to dmc notifier, and we can > get the dmc status.
If you want to know when ddr frequency is chanaged, you can use the DEVFREQ_TRANSITION_NOTIFIER notifier[1] (merged to v4.7-rc1) which includes the following notification: - DEVFREQ_PRECHANGE - DEVFREQ_POSTCHANGE [1] "PM / devfreq: Add new DEVFREQ_TRANSITION_NOTIFIER notifier" - https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=0fe3a66410a3ba96679be903f1e287d7a0a264a9 Thanks, Chanwoo Choi > > Signed-off-by: Lin Huang <hl at rock-chips.com> > --- > > Changes in v2: > - None > > Changes in v1: > - use wait_event instead usleep > > drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 43 > +++++++++++++++++++++++++++-- > 1 file changed, 41 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c > b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c > index 1c4d5b5..8286048 100644 > --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c > +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c > @@ -31,6 +31,8 @@ > #include <linux/reset.h> > #include <linux/delay.h> > > +#include <soc/rockchip/rockchip_dmc.h> > + > #include "rockchip_drm_drv.h" > #include "rockchip_drm_gem.h" > #include "rockchip_drm_fb.h" > @@ -116,6 +118,10 @@ struct vop { > > const struct vop_data *data; > > + struct notifier_block dmc_nb; > + int dmc_in_process; > + wait_queue_head_t wait_dmc_queue; > + > uint32_t *regsbak; > void __iomem *regs; > > @@ -426,6 +432,21 @@ static void vop_dsp_hold_valid_irq_disable(struct vop > *vop) > spin_unlock_irqrestore(&vop->irq_lock, flags); > } > > +static int dmc_notify(struct notifier_block *nb, unsigned long event, > + void *data) > +{ > + struct vop *vop = container_of(nb, struct vop, dmc_nb); > + > + if (event == DMCFREQ_ADJUST) { > + vop->dmc_in_process = 1; > + } else if (event == DMCFREQ_FINISH) { > + vop->dmc_in_process = 0; > + wake_up(&vop->wait_dmc_queue); > + } > + > + return NOTIFY_OK; > +} > + > static void vop_enable(struct drm_crtc *crtc) > { > struct vop *vop = to_vop(crtc); > @@ -434,6 +455,13 @@ static void vop_enable(struct drm_crtc *crtc) > if (vop->is_enabled) > return; > > + /* > + * if in dmc scaling frequency process, wait until it finish > + * use 100ms as timeout time. > + */ > + wait_event_timeout(vop->wait_dmc_queue, > + !vop->dmc_in_process, HZ / 10); > + > ret = pm_runtime_get_sync(vop->dev); > if (ret < 0) { > dev_err(vop->dev, "failed to get pm runtime: %d\n", ret); > @@ -485,6 +513,7 @@ static void vop_enable(struct drm_crtc *crtc) > enable_irq(vop->irq); > > drm_crtc_vblank_on(crtc); > + rockchip_dmc_get(&vop->dmc_nb); > > return; > > @@ -505,6 +534,13 @@ static void vop_crtc_disable(struct drm_crtc *crtc) > return; > > /* > + * if in dmc scaling frequency process, wait until it finish > + * use 100ms as timeout time. > + */ > + wait_event_timeout(vop->wait_dmc_queue, > + !vop->dmc_in_process, HZ / 10); > + > + /* > * We need to make sure that all windows are disabled before we > * disable that crtc. Otherwise we might try to scan from a destroyed > * buffer later. > @@ -517,7 +553,7 @@ static void vop_crtc_disable(struct drm_crtc *crtc) > VOP_WIN_SET(vop, win, enable, 0); > spin_unlock(&vop->reg_lock); > } > - > + rockchip_dmc_put(&vop->dmc_nb); > drm_crtc_vblank_off(crtc); > > /* > @@ -1243,7 +1279,7 @@ static int vop_create_crtc(struct vop *vop) > ret = -ENOENT; > goto err_cleanup_crtc; > } > - > + vop->dmc_nb.notifier_call = dmc_notify; > init_completion(&vop->dsp_hold_completion); > init_completion(&vop->wait_update_complete); > crtc->port = port; > @@ -1465,6 +1501,9 @@ static int vop_bind(struct device *dev, struct device > *master, void *data) > /* IRQ is initially disabled; it gets enabled in power_on */ > disable_irq(vop->irq); > > + init_waitqueue_head(&vop->wait_dmc_queue); > + vop->dmc_in_process = 0; > + > ret = vop_create_crtc(vop); > if (ret) > return ret; >
