[lkml]   [2020]   [Feb]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH AUTOSEL 5.5 219/542] ARM: OMAP2+: use separate IOMMU pdata to fix DRA7 IPU1 boot
On Fri, Feb 14, 2020 at 12:34:58PM -0600, Suman Anna wrote:
>Hi Sasha,
>On 2/14/20 9:43 AM, Sasha Levin wrote:
>> From: Suman Anna <>
>> [ Upstream commit 4601832f40501efc3c2fd264a5a69bd1ac17d520 ]
>> The IPU1 MMU has been using common IOMMU pdata quirks defined and
>> used by all IPU IOMMU devices on OMAP4 and beyond. Separate out the
>> pdata for IPU1 MMU with the additional .set_pwrdm_constraint ops
>> plugged in, so that the IPU1 power domain can be restricted to ON
>> state during the boot and active period of the IPU1 remote processor.
>> This eliminates the pre-conditions for the IPU1 boot issue as
>> described in commit afe518400bdb ("iommu/omap: fix boot issue on
>> remoteprocs with AMMU/Unicache").
>> NOTE:
>> 1. RET is not a valid target power domain state on DRA7 platforms,
>> and IPU power domain is normally programmed for OFF. The IPU1
>> still fails to boot though, and an unclearable l3_noc error is
>> thrown currently on 4.14 kernel without this fix. This behavior
>> is slightly different from previous 4.9 LTS kernel.
>> 2. The fix is currently applied only to IPU1 on DRA7xx SoC, as the
>> other affected processors on OMAP4/OMAP5/DRA7 are in domains
>> that are not entering RET. IPU2 on DRA7 is in CORE power domain
>> which is only programmed for ON power state. The fix can be easily
>> scaled if these domains do hit RET in the future.
>> 3. The issue was not seen on current DRA7 platforms if any of the
>> DSP remote processors were booted and using one of the GPTimers
>> 5, 6, 7 or 8 on previous 4.9 LTS kernel. This was due to the
>> errata fix for i874 implemented in commit 1cbabcb9807e ("ARM:
>> DRA7: clockdomain: Implement timer workaround for errata i874")
>> which keeps the IPU1 power domain from entering RET when the
>> timers are active. But the timer workaround did not make any
>> difference on 4.14 kernel, and an l3_noc error was seen still
>> without this fix.
>> Signed-off-by: Suman Anna <>
>> Signed-off-by: Tony Lindgren <>
>> Signed-off-by: Sasha Levin <>
>And drop this one as well, since mainline doesn't yet boot
>the processors, so this is not needed for stable queue.

Now dropped, thank you.


 \ /
  Last update: 2020-02-20 17:50    [W:0.301 / U:2.812 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site