On 2015年02月02日 15:53, Daniel Vetter wrote:
On Mon, Feb 02, 2015 at 10:30:09AM +0800, Mark yao wrote:
On 2015年02月02日 10:07, Daniel Kurtz wrote:
Hi Mark, Heiko,
On Sat, Jan 31, 2015 at 4:41 PM, Mark Yao mark.yao@rock-chips.com wrote:
Vop standby will take effect end of current frame, if dsp_hold_valid_irq happen, it means vop standby complete.
we must wait standby complete when we want to disable aclk, if not, memory bus maybe dead.
Signed-off-by: Mark Yao mark.yao@rock-chips.com
drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 76 ++++++++++++++++++++++----- 1 file changed, 63 insertions(+), 13 deletions(-)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c index fb25836..47ea61f 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -89,6 +89,7 @@ struct vop { /* mutex vsync_ work */ struct mutex vsync_mutex; bool vsync_work_pending;
struct completion dsp_hold_completion; const struct vop_data *data;@@ -382,6 +383,34 @@ static bool is_alpha_support(uint32_t format) } }
+static void vop_dsp_hold_valid_irq_enable(struct vop *vop) +{
unsigned long flags;BUG_ON(!vop->is_enabled);Re: Heiko "use a WARN_ON":
If the VOP clock is off, then the system will just hang when trying to write the VOP register so in this case, BUG_ON gives a more reliable crash dump than the hang.
In this way, you are right, if vop clocks is disabled, write vop register will hang system, and the WARN_ON
if (WARN_ON(cond)) return;
is what we commonly use in i915. Because it's really not any good to use BUG_ON in drm drivers, at least if you expect anyone to use fbcon on top of it (i.e. anything even remotely resembling a normal distro): Then the intial modeset is all done under console_lock, which means that _none_ of your BUG_ON will ever get out over serial console.
The problem is fbcon locking, but no fool yet signed up to fix it (it's horrible, I looked ...). -Daniel
I know this problem, if fbcon locking, and BUG_ON, we can't get any log from serial console, Trouble me many times. So know, if no drm log output, the first thing I do is remove the fbcon lock, and then we can see the crash dump.
But here, I expect to use BUG_ON, because if BUG happen, vop register will hang system, and WARN_ON may be have no chance to output.
Mark