On Tue, 2021-11-30 at 13:33 +0200, Dafna Hirschfeld wrote:

On 30.11.21 09:39, Yong Wu wrote:

quoted

On Sat, 2021-11-27 at 12:11 +0200, Dafna Hirschfeld wrote:

quoted

On 10.11.21 09:50, Yong Wu wrote:

quoted

On Wed, 2021-11-10 at 07:29 +0200, Dafna Hirschfeld wrote:

quoted

On 10.11.21 04:20, Yong Wu wrote:

quoted

On Tue, 2021-11-09 at 14:21 +0200, Dafna Hirschfeld wrote:

quoted

Hi
This patch is needed in order to update the tlb when a
device
is
powered on.
Could you send this patch alone without the whole series
so
it
get
accepted easier?

Which SoC are you testing on? In previous SoC, the IOMMU HW
don't
have
power-domain, and we have a "has_pm"[1] in the tlb function
for
that
case. The "has_pm" should be always 0 for the previous SoC
like
mt8173,
it should always tlb synchronize.

thus, Could you help share more about your issue? In which
case
it
lack
the necessary tlb operation. At least, We need confirm if
it
needs
a
"Fixes" tags if sending this patch alone.

Hi,
I work with the mtk-vcodec driver on mt8173. As you wrote,
the
iommu
doesn't
have a power-domain and so when allocating buffers before the
device
is powered
on, there is the warning
"Partial TLB flush timed out, falling back to full flush"
flooding the log buf.

oh. Thanks very much for your information. Get it now.

This issue should be introduced by the:

b34ea31fe013 ("iommu/mediatek: Always enable the clk on
resume")

Hi, reverting this commit didn't solve those warnings,
I think this is because in the function mtk_iommu_attach_device
the first call to pm_runtime_resume_and_get does not turn the
clks on
since m4u_dom is not yet initialize. And then
mtk_iommu_attach_device
calls pm_runtime_put right after mtk_iommu_hw_init is called
(where the clks are turned on)

oh. Right. this is also related with the patch of "Add power-domain
operation".

The current problem is that there is a redundant log of "Partial
TLB
flush timed out" in mt8173. We need fix this issue firstly. Are you
going to prepare the patches again? If not, I could help this. You
could help confirm them if you are free.

Hi,
I already sent a patch last week: 
https://lore.kernel.org/linux-iommu/afb46ad6ca9477a2bf71233858406caa6ccb1588.camel@mediatek.com/T/ (local)
could you please review it?

I have replied them before you send this reply. Have you got them?


https://lore.kernel.org/linux-iommu/afb46ad6ca9477a2bf71233858406caa6ccb1588.camel@mediatek.com/ (local)

https://lore.kernel.org/linux-iommu/6abef78f6447c626b737fd35688f421c29871f43.camel@mediatek.com/ (local)

Thanks.

Thanks,
Dafna

quoted

Thanks.

quoted

thanks,
Dafna

quoted

tlb failed due to the bclk is not enabled. Could you help try
that
after reverting this?

quoted

Sebastian Reichel suggested to remove the 'if(has_pm)' check
to
avoid
this warning,
and avoid flushing the tlb if the device is off:

[1] http://ix.io/3Eyr

This fixes the warning, but then the tlb is not flushed in
sync,
Therefore the tlb should be flushed when the device is
resumed.

So the two patches (the one suggested in the link [1] and
this
patch)
should be sent together as a 2-patch series.

then this is reasonable. You could help this into a new
patchset if
you
are free(add Fixes tag).

Thanks.

quoted

Thanks,
Dafna

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel