Re: [PATCH] ARM: OMAP3: Fix iva2_pwrdm settings for 3703

From: Yegor Yefremov <yegorslists@googlemail.com>
To: Tony Lindgren <tony@atomide.com>
Cc: "Mark A. Greer" <mgreer@animalcreek.com>,
	Yegor Yefremov <yegor_sub1@visionsystems.de>,
	Kevin Hilman <khilman@linaro.org>, Paul Walmsley <paul@pwsan.com>,
	linux-omap@vger.kernel.org,
	linux-arm-kernel <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH] ARM: OMAP3: Fix iva2_pwrdm settings for 3703
Date: Tue, 21 May 2013 11:17:16 +0200	[thread overview]
Message-ID: <CAGm1_ku3Fgib8+ZkF0XOq6K9QxY80dAMZAP65uz4jpMEXQtWLg@mail.gmail.com> (raw)
In-Reply-To: <20130520220540.GL10378@atomide.com>

On Tue, May 21, 2013 at 12:05 AM, Tony Lindgren <tony@atomide.com> wrote:
> * Yegor Yefremov <yegorslists@googlemail.com> [130517 14:34]:
>> On Fri, May 17, 2013 at 8:56 PM, Mark A. Greer <mgreer@animalcreek.com> wrote:
>> > On Thu, May 16, 2013 at 12:19:20PM +0200, Yegor Yefremov wrote:
>> >> On 15.05.2013 23:50, Mark A. Greer wrote:
>> >> > On Wed, May 15, 2013 at 10:07:35AM -0700, Tony Lindgren wrote:
>> >
>> >> >> Mark, do you have some omap3 with no iva (other than am3703) to test the
>> >> >> idle states with?
>> >> >
>> >> > I have an am35xx which isn't supposed to have an IVA so I can test with it
>> >> > (although, I'm not sure how well the kernel works on the am35xx these days).
>> >> >
>> >> > I'm a bit busy today but I'll try booting the am35xx tomorrow and if it
>> >> > comes up, see what I can figure out.
>> >>
>> >> I think this issue is relevant to am3517 as you can see from this thread: http://thread.gmane.org/gmane.linux.ports.arm.omap/97903
>> >> I could boot only with your patch http://www.spinics.net/lists/arm-kernel/msg168865.html
>> >>
>> >> I have such a system running, so if you have any other patches/ideas to test, I would do it.
>> >
>> > Yegor, since I've so far been unable to get my am3517evm to fire up, can
>> > you play around with the 3517 to see if there appears to be iva registers
>> > that can be read/written to safely?  In particular, can the code that idles
>> > the iva be run safely on an am3517?
>>
>> I'll look into this next week. am3517 and IVA seems to be a really big
>> mystery. In the TI forum will be stated, there is no IVA:
>> http://e2e.ti.com/support/arm/sitara_arm/f/791/t/150961.aspx, but TRM
>> has various appearances of IVA2 registers, but no real
>> description/explanation of what is IVA and how to eat it.
>
> On 3703 it looks like the whole omap3_iva_idle() reset is needed, except
> for setting the iva2 bootmode to idle. So I'm planning to merge the following
> patch with just comments update this week unless somebody has a better fix
> in mind.

calling omap3_iva_idle() made no difference so far. I still can boot
3.10-rc2 with 'nohlt' and omap3_iva_idle() and vice versa, without
'nohlt' I cannot boot whether with or without calling
omap3_iva_idle().

BTW Tony I've sent a patch to fix MUSB clock naming. Should I also
make a recent including linux-usb mailing list or can we handle this
internally on omap/arm list?

Yegor