lkml.org 
[lkml]   [2021]   [Feb]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] iommu/tegra-smmu: Fix mc errors on tegra124-nyan
From
Date
19.02.2021 01:07, Nicolin Chen пишет:
> Commit 25938c73cd79 ("iommu/tegra-smmu: Rework tegra_smmu_probe_device()")
> removed certain hack in the tegra_smmu_probe() by relying on IOMMU core to
> of_xlate SMMU's SID per device, so as to get rid of tegra_smmu_find() and
> tegra_smmu_configure() that are typically done in the IOMMU core also.
>
> This approach works for both existing devices that have DT nodes and other
> devices (like PCI device) that don't exist in DT, on Tegra210 and Tegra3
> upon testing. However, Page Fault errors are reported on tegra124-Nyan:
>
> tegra-mc 70019000.memory-controller: display0a: read @0xfe056b40:
> EMEM address decode error (SMMU translation error [--S])
> tegra-mc 70019000.memory-controller: display0a: read @0xfe056b40:
> Page fault (SMMU translation error [--S])
>
> After debugging, I found that the mentioned commit changed some function
> callback sequence of tegra-smmu's, resulting in enabling SMMU for display
> client before display driver gets initialized. I couldn't reproduce exact
> same issue on Tegra210 as Tegra124 (arm-32) differs at arch-level code.

Hello Nicolin,

Could you please explain in a more details what exactly makes the
difference for the callback sequence?

\
 
 \ /
  Last update: 2021-02-20 06:18    [W:0.134 / U:4.076 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site