From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chanwoo Choi Subject: Re: [RFC PATCH v2 6/6] drm/rockchip: Add dmc notifier in vop driver Date: Thu, 23 Jun 2016 10:19:06 +0900 Message-ID: <576B390A.3050905@samsung.com> References: <1465207986-17888-1-git-send-email-hl@rock-chips.com> <1465207986-17888-7-git-send-email-hl@rock-chips.com> <576A3A38.3000306@samsung.com> <576A83A0.3080908@rock-chips.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-reply-to: <576A83A0.3080908@rock-chips.com> Sender: linux-clk-owner@vger.kernel.org To: hl , heiko@sntech.de, mark.yao@rock-chips.com, myungjoo.ham@samsung.com Cc: mturquette@baylibre.com, sboyd@codeaurora.org, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, airlied@linux.ie, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, kyungmin.park@samsung.com, dianders@chromium.org, dbasehore@chromium.org List-Id: linux-rockchip.vger.kernel.org Hi Lin, On 2016=EB=85=84 06=EC=9B=94 22=EC=9D=BC 21:25, hl wrote: > Hi Chanwoo Choi, >=20 > On 2016=E5=B9=B406=E6=9C=8822=E6=97=A5 15:11, Chanwoo Choi wrote: >> Hi, >> >> On 2016=EB=85=84 06=EC=9B=94 06=EC=9D=BC 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 v= 4.7-rc1) >> which includes the following notification: >> - DEVFREQ_PRECHANGE >> - DEVFREQ_POSTCHANGE=09 >> >> [1] "PM / devfreq: Add new DEVFREQ_TRANSITION_NOTIFIER notifier" >> - https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/co= mmit/?id=3D0fe3a66410a3ba96679be903f1e287d7a0a264a9 > Check the code, if the set target fail, it will not send DEVFREQ_POST= CHANGE, but in our case, whether the target > setting sucess or fail, it should send message to vop driver, tell v= op driver dmc have finish frequency setting. I check the code when target function is failed. DEVFREQ_TRANSITION_NOTIFIER notifier[1] is missing the error case as yo= u mentioned. So, we would add following patches to fix the problem. diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 1d6c803804d5..2bd9d4228b7b 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -268,8 +268,10 @@ int update_devfreq(struct devfreq *devfreq) devfreq_notify_transition(devfreq, &freqs, DEVFREQ_PRECHANGE); =20 err =3D devfreq->profile->target(devfreq->dev.parent, &freq, fl= ags); - if (err) + if (err) { + freqs.new =3D cur_freq; + devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POST= CHANGE); return err; + } =20 freqs.new =3D freq; devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); Thanks, Chanwoo Choi >> >> Thanks, >> Chanwoo Choi >> >>> Signed-off-by: Lin Huang >>> --- >>> >>> 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 >>> #include >>> =20 >>> +#include >>> + >>> #include "rockchip_drm_drv.h" >>> #include "rockchip_drm_gem.h" >>> #include "rockchip_drm_fb.h" >>> @@ -116,6 +118,10 @@ struct vop { >>> =20 >>> const struct vop_data *data; >>> =20 >>> + struct notifier_block dmc_nb; >>> + int dmc_in_process; >>> + wait_queue_head_t wait_dmc_queue; >>> + >>> uint32_t *regsbak; >>> void __iomem *regs; >>> =20 >>> @@ -426,6 +432,21 @@ static void vop_dsp_hold_valid_irq_disable(str= uct vop *vop) >>> spin_unlock_irqrestore(&vop->irq_lock, flags); >>> } >>> =20 >>> +static int dmc_notify(struct notifier_block *nb, unsigned long eve= nt, >>> + void *data) >>> +{ >>> + struct vop *vop =3D container_of(nb, struct vop, dmc_nb); >>> + >>> + if (event =3D=3D DMCFREQ_ADJUST) { >>> + vop->dmc_in_process =3D 1; >>> + } else if (event =3D=3D DMCFREQ_FINISH) { >>> + vop->dmc_in_process =3D 0; >>> + wake_up(&vop->wait_dmc_queue); >>> + } >>> + >>> + return NOTIFY_OK; >>> +} >>> + >>> static void vop_enable(struct drm_crtc *crtc) >>> { >>> struct vop *vop =3D to_vop(crtc); >>> @@ -434,6 +455,13 @@ static void vop_enable(struct drm_crtc *crtc) >>> if (vop->is_enabled) >>> return; >>> =20 >>> + /* >>> + * 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 =3D 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); >>> =20 >>> drm_crtc_vblank_on(crtc); >>> + rockchip_dmc_get(&vop->dmc_nb); >>> =20 >>> return; >>> =20 >>> @@ -505,6 +534,13 @@ static void vop_crtc_disable(struct drm_crtc *= crtc) >>> return; >>> =20 >>> /* >>> + * 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 destr= oyed >>> * buffer later. >>> @@ -517,7 +553,7 @@ static void vop_crtc_disable(struct drm_crtc *c= rtc) >>> VOP_WIN_SET(vop, win, enable, 0); >>> spin_unlock(&vop->reg_lock); >>> } >>> - >>> + rockchip_dmc_put(&vop->dmc_nb); >>> drm_crtc_vblank_off(crtc); >>> =20 >>> /* >>> @@ -1243,7 +1279,7 @@ static int vop_create_crtc(struct vop *vop) >>> ret =3D -ENOENT; >>> goto err_cleanup_crtc; >>> } >>> - >>> + vop->dmc_nb.notifier_call =3D dmc_notify; >>> init_completion(&vop->dsp_hold_completion); >>> init_completion(&vop->wait_update_complete); >>> crtc->port =3D port; >>> @@ -1465,6 +1501,9 @@ static int vop_bind(struct device *dev, struc= t device *master, void *data) >>> /* IRQ is initially disabled; it gets enabled in power_on */ >>> disable_irq(vop->irq); >>> =20 >>> + init_waitqueue_head(&vop->wait_dmc_queue); >>> + vop->dmc_in_process =3D 0; >>> + >>> ret =3D vop_create_crtc(vop); >>> if (ret) >>> return ret; >>> >> >> >> >=20 > --=20 > Lin Huang >=20