From: archit@ti•com (Archit Taneja)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH] ARM: OMAP5: DSS hwmod data
Date: Thu, 8 May 2014 11:18:12 +0530 [thread overview]
Message-ID: <536B1A9C.7050006@ti.com> (raw)
In-Reply-To: <alpine.DEB.2.02.1405080432570.23579@utopia.booyaka.com>
Hi Paul,
On Thursday 08 May 2014 10:07 AM, Paul Walmsley wrote:
> Hi,
>
> On Wed, 12 Mar 2014, Tomi Valkeinen wrote:
>
>> This patch adds hwmod data for omap5 display subsystem. I have tested this on
>> omap5-uevm with a DSI panel. I cannot test omap5-uevm's hdmi output yet, as the
>> mainline is missing omap5 HDMI driver.
>>
>> I do see this when booting:
>>
>> omap_hwmod: dss_dispc: cannot be enabled for reset (3)
>> omap_hwmod: dss_dsi1: cannot be enabled for reset (3)
>> omap_hwmod: dss_dsi2: cannot be enabled for reset (3)
>> omap_hwmod: dss_hdmi: cannot be enabled for reset (3)
>> omap_hwmod: dss_rfbi: cannot be enabled for reset (3)
>>
>> But at least DSI works just fine.
>
> Am looking at this for v3.16. But I think someone needs to take a look at
> those warnings and figure out why they are happening.
We associate DSS clock domain's MODULEMODE bits only with the dss_core
hwmod. The rest of the dss hwmods don't touch MODULEMODE.
Therefore, these hwmods cannot be enabled independently, and reset.
We don't face this issue in the omapdss driver since the platform
devices corresponding to these hwmods have their parent as the platform
device corresponding to 'dss_core'. This parent child-relation ensures
that 'dss_core' is enabled when the a child calls a pm_runtime_get function.
The problem is that we have multiple hwmods which use the same
MODULEMODE bit. There is no use-counting done when it comes to
enabling/disabling modulemode. If there was such a thing, we could have
provided MODULEMODE flags even for the children hwmods.
>
> Is the soc_ops.wait_target_ready() call failing in omap_hwmod.c:_enable()
> ?
Yes, that's the one that fails.
We have the same DSS in OMAP4, but we don't see the issue there. That's
because we have modeled the MODULEMODE bits as a fake interface clock.
That lets us enable hwmods independently, but it messes up DSS PM as it
breaks some rules related to the sequence in which the opt-clocks and
MODULEMODE bits need to be disabled.
We would want to change OMAP4 to work the way as above too, with the
cost of having these prints above.
Archit
next prev parent reply other threads:[~2014-05-08 5:48 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-12 10:26 [PATCH] ARM: OMAP5: DSS hwmod data Tomi Valkeinen
2014-03-12 10:26 ` [PATCH] ARM: OMAP5: Add omap5 DSS related " Tomi Valkeinen
2014-03-12 10:33 ` [PATCH] ARM: OMAP5: DSS " Tomi Valkeinen
2014-03-16 11:41 ` Dmitry Lifshitz
2014-03-17 6:13 ` Tomi Valkeinen
2014-03-17 13:22 ` Dmitry Lifshitz
2014-03-17 13:28 ` Tomi Valkeinen
2014-03-17 14:22 ` Dmitry Lifshitz
2014-03-18 5:29 ` Tomi Valkeinen
2014-03-18 8:19 ` Dmitry Lifshitz
2014-03-18 8:37 ` Tomi Valkeinen
2014-03-18 12:23 ` Dmitry Lifshitz
2014-05-08 4:37 ` Paul Walmsley
2014-05-08 5:48 ` Archit Taneja [this message]
2014-05-08 16:01 ` Paul Walmsley
2014-05-09 6:19 ` Archit Taneja
2014-05-09 6:36 ` Tomi Valkeinen
2014-05-14 19:44 ` Paul Walmsley
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=536B1A9C.7050006@ti.com \
--to=archit@ti$(echo .)com \
--cc=linux-arm-kernel@lists$(echo .)infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox