On 16 March 2016 at 16:23, Tomeu Vizoso tomeu@tomeuvizoso.net wrote:
On 15 March 2016 at 02:30, Mark yao mark.yao@rock-chips.com wrote:
On 2016年03月14日 21:35, Tomeu Vizoso wrote:
On 2 December 2014 at 10:15, Mark Yao mark.yao@rock-chips.com wrote:
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c new file mode 100644 index 0000000..e7ca25b --- /dev/null +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -0,0 +1,1455 @@
...
+static bool vop_crtc_mode_fixup(struct drm_crtc *crtc,
const struct drm_display_mode *mode,struct drm_display_mode *adjusted_mode)+{
if (adjusted_mode->htotal == 0 || adjusted_mode->vtotal == 0)return false;Hi Mark,
what's the rationale for this?
Disabling a CRTC as in [0] will cause mode_fixup() to be called with an empty mode, failing that test.
Removing the check seems to get things working fine for a short while, but a later modeset invariably gets the VOP to hang (as reported by [1]).
Do you know why that check was put in place and what exactly could be causing the hw to hang?
[0] https://cgit.freedesktop.org/xorg/app/intel-gpu-tools/tree/lib/igt_kms.c#n16... [1] https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/driver...
Thanks,
Tomeu
Hi Tomeu
Just thinking that "adjusted_mode->htotal == 0 || adjusted_mode->vtotal == 0" is not a good mode for vop.
Ah, ok. Guess it should be removed then so we don't break userspace?
And you said VOP hang, only WARN_ON error message? or system hang, die?
Sorry, the symptom was only the warning, I just went a bit too far and assumed the VOP had stopped working at all.
I think maybe crtc disable too fast, vblank is off, then no one can feed the wait_update_complete. Can you test it again with following patch?
Actually, in today's testing I don't see that happening any more, sorry about that :/
What I have been looking at today is a related issue when running the kms_flip_event_leak test from intel-gpu-tools. If I remove the check mentioned above so CRTCs can be disabled with the SetCRTC IOCTL, I see this page fault the second and subsequent times I run the test.
[ 75.809031] rk_iommu ff930300.iommu: Page fault at 0x01000000 of type read [ 75.809035] rk_iommu ff930300.iommu: iova = 0x01000000: dte_index: 0x4 pte_index: 0x0 page_offset: 0x0 [ 75.809040] rk_iommu ff930300.iommu: mmu_dte_addr: 0x2c258000 dte@0x2c258010: 0x2c561001 valid: 1 pte@0x2c561000: 0x2a000006 valid: 0 page@0x00000000 flags: 0x0 [ 76.951288] rk_iommu ff930300.iommu: Enable stall request timed out, status: 0x00004b
I have written a smaller standalone test that is attached in case you want to check it out, but I haven't been able to find out why it only happens when the test is rerun.
Apparently the VOP is still trying to read a BO (0x01000000) right when the kernel frees it, but from what I can see, it should be scanning another BO at that point.
Do you have any ideas on what could be happening?
Apparently, when the VOP is re-enabled, it will start scanning from the framebuffer address that had been set last.
Because DMA addresses are recycled and there's going to be a low number of framebuffers, this isn't going to be obvious unless we make sure that there isn't a FB allocated at that DMA address any more.
The attached test case does just that.
Regards,
Tomeu
Thanks,
Tomeu
drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -503,6 +503,8 @@ static void vop_crtc_disable(struct drm_crtc *crtc) if (!vop->is_enabled) return;
vop_crtc_wait_for_update(crtc);drm_crtc_vblank_off(crtc);Thanks.
-- Ｍark Yao