Re: [RFC PATCH 7/9] drm/rockchip: force enable vop when do mode setting

From: Mark yao
Date: Wed Dec 02 2015 - 20:55:16 EST


On 2015å12æ03æ 06:17, Daniel Vetter wrote:
On Wed, Dec 02, 2015 at 05:55:36PM +0100, Thierry Reding wrote:
On Tue, Dec 01, 2015 at 11:32:01AM +0800, Mark Yao wrote:
When do mode setting, mean that we want to enable display output,
but sometimes, vop_crtc_enable is after mode_set, we can't allow
that, so force enable vop in mode setting.

Signed-off-by: Mark Yao <mark.yao@xxxxxxxxxxxxxx>
---
drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
index c65b454..7c07537 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
@@ -1110,6 +1110,7 @@ static void vop_crtc_mode_set_nofb(struct drm_crtc *crtc)
u16 vact_end = vact_st + vdisplay;
uint32_t val;
+ vop_crtc_enable(crtc);
/*
* If dclk rate is zero, mean that scanout is stop,
* we don't need wait any more.
Have you considered simply moving everything into ->enable()? That's
what I did for Tegra, for much the same reasons that you gave in the
commit message. Doing so gives you a much simpler call graph. Really
the only thing you need to do is move around the code, and perhaps a
different way to get ahold of the display mode, but you can use the
Tegra driver as a reference for how to do that.
Yeah if writing mode related registers requires the thing to be on on your
hw then you can't use the ->mode_set hooks. Those are explicitly called
when everything is off (not just sometimes, at least with atomic helpers).

Like Thierry said the recommendation is to just shovel that code into
->enable hooks. ->mode_set_nofb is mostly there to support easier
transition for drivers which started with the legacy crtc helpers.
-Daniel

Good, thanks, actually it solve my confusion.

--
ïark Yao


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