Hi Tomi, On Wed, Feb 12, 2014 at 2:18 PM, Tomi Valkeinen <tomi.valkeinen@xxxxxx> wrote: > Hi Tero, Christoph, > > On 07/02/14 12:12, Christoph Fritz wrote: >> On Tue, 2014-02-04 at 17:50 +0200, Tero Kristo wrote: >>> On 01/29/2014 01:21 PM, Christoph Fritz wrote: >>>>> Currently I only analyzed sys_clkout2 (see attachments for full >>>>> clk_summary files): >>>>> >>>>> clk_summary__next-20140115__works_as_expected: >>>>> dpll4_m2_ck 1 1 96000000 >>>>> dpll4_m2x2_ck 1 1 96000000 >>>>> omap_192m_alwon_fck 1 1 96000000 >>>>> omap_96m_alwon_fck 1 2 96000000 >>>>> per_96m_fck 0 6 96000000 >>>>> mcbsp4_fck 0 1 96000000 >>>>> mcbsp3_fck 0 2 96000000 >>>>> mcbsp2_fck 0 2 96000000 >>>>> cm_96m_fck 2 3 96000000 >>>>> clkout2_src_ck 1 1 96000000 >>>>> sys_clkout2 1 1 24000000 >>>>> >>>>> For real, on pin sys_clkout2 are correctly 24 Mhz measured. >>>>> >>>>> clk_summary__next-20140124__sysclkout2_dss_fails: >>>>> dpll4_m2_ck 1 1 96000000 >>>>> dpll4_m2x2_mul_ck 1 1 192000000 >>>>> dpll4_m2x2_ck 1 1 192000000 >>>>> omap_192m_alwon_fck 0 0 192000000 >>>>> omap_96m_alwon_fck 1 2 192000000 >>>>> per_96m_fck 0 6 192000000 >>>>> mcbsp4_fck 0 1 192000000 >>>>> mcbsp3_fck 0 2 192000000 >>>>> mcbsp2_fck 0 2 192000000 >>>>> cm_96m_fck 2 3 192000000 >>>>> clkout2_src_ck 1 1 192000000 >>>>> sys_clkout2 1 1 24000000 >>>>> >>>>> For real, on pin sys_clkout2 are only ~12 Mhz measured. >>> >>> Hey Christoph, >>> >>> I had a chance to look at this in more detail, and it looks like your >>> patch above was almost the correct one (except that I think you modified >>> wrong property and also modified the clock node for all omap3 variants.) >>> Can you give this one a shot? Can you also send me the clk-summary dump >>> with this patch (with the relevant nodes)? >> >> dpll4_m2_ck 1 1 96000000 0 >> dpll4_m2x2_mul_ck 1 1 192000000 0 >> dpll4_m2x2_ck 1 1 192000000 0 >> omap_192m_alwon_fck 0 0 192000000 0 >> omap_96m_alwon_fck 1 2 96000000 0 >> per_96m_fck 0 6 96000000 0 >> mcbsp4_fck 0 1 96000000 0 >> mcbsp3_fck 0 2 96000000 0 >> mcbsp2_fck 0 2 96000000 0 >> cm_96m_fck 2 3 96000000 0 >> clkout2_src_ck 1 1 96000000 0 >> sys_clkout2 1 1 24000000 0 >> >> Yes, your patch fixes the issues for sys_clkout2. Thanks! If you want, >> you can add my: >> Tested-by: Christoph Fritz <chf.fritz@xxxxxxxxxxxxxx> >> >> Below is my clock fix for dss: >> >> From b90a62128068e1b6b0ba2a11c5cc0c8e587cf301 Mon Sep 17 00:00:00 2001 >> From: Christoph Fritz <chf.fritz@xxxxxxxxxxxxxx> >> Date: Fri, 7 Feb 2014 10:51:15 +0100 >> Subject: [PATCH] ARM: dts: omap36xx: fix dpll4_m4_ck tree > > Ookay, I finally got Beagle xM working with DSS DT. So, to summarize the > problem: DPLL4 on omap3630 is a Type B DPLL. Type B DPLL does not have > x2 multiplier like other DPLLs. Afaik, DPLL4 on 3630 is the only Type B > DPLL on OMAP3 SoCs. > > Tero's patch fixed 96m clock, which comes from dpll4_m2, by adding an > extra /2 divider to that clock path. So the 96m clock first gets > mutiplied by 2, even though the HW doesn't do that, and then divided by > 2, even though the HW doesn't do that. > > Christoph's patch fixes DSS fclk, which comes from dpll4_m4, by skipping > the x2 clock nodes totally, which is much better. However, it leaves the > old x2 clock nodes there, and when dpll4_m4 clock rate changes (as it > does when omapdss sets the fclk), the unused x2 clocks do recalcs, > breaking everything. This last bit is a bit guesswork, I didn't actually > verify it, but the fact is that if I remove the x2 clocks totally, > omapdss work fine. > > Sooo... What should be done is create new DPLL4 clock paths for > OMAP3630, which do not have the x2 clocks at all. I tried to do that, > but it wasn't trivial (at least to me who is not so familiar with the > clock data in DT). > > However, I hacked together the patch below, which "fixes" the issue for > 96m and dss fclk. It sets the clock parents so that the x2 clocks are > skipped, and makes the x2 clock nodes compatible with "unused", making > them effectively disappear. I only verified dss fclk, so Christoph, can > you verify the 96m clock? With below hack dss v3 (rebased on top 3.14-rc2) works (without it fails to probe). > > Tomi > > From ab29f9a3a43d95cdf06421bd9f29c4d7418f37de Mon Sep 17 00:00:00 2001 > From: Tomi Valkeinen <tomi.valkeinen@xxxxxx> > Date: Wed, 12 Feb 2014 15:07:03 +0200 > Subject: [PATCH] HACK: OMAP3630: fix for 96m and dss fclks > > --- > arch/arm/boot/dts/omap36xx-clocks.dtsi | 26 ++++++++++++++++++++++++++ > arch/arm/boot/dts/omap36xx.dtsi | 2 +- > 2 files changed, 27 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/boot/dts/omap36xx-clocks.dtsi > b/arch/arm/boot/dts/omap36xx-clocks.dtsi > index 2fcf253b677c..9fe91ebf41fd 100644 > --- a/arch/arm/boot/dts/omap36xx-clocks.dtsi > +++ b/arch/arm/boot/dts/omap36xx-clocks.dtsi > @@ -70,6 +70,32 @@ > }; > }; > > +/* HACK to skip x2 multiplier for 96m clock */ > +&omap_96m_alwon_fck { > + clocks = <&dpll4_m2_ck>; > +}; > + > +&dpll4_m2x2_mul_ck { > + compatible = "unused"; > +}; > + > +&dpll4_m2x2_ck { > + compatible = "unused"; > +}; > + > +/* HACK to skip x2 multiplier for dss clock */ > +&dss1_alwon_fck_3430es2 { > + clocks = <&dpll4_m4_ck>; > +}; > + > +&dpll4_m4x2_mul_ck { > + compatible = "unused"; > +}; > + > +&dpll4_m4x2_ck { > + compatible = "unused"; > +}; > + > &cm_clockdomains { > dpll4_clkdm: dpll4_clkdm { > compatible = "ti,clockdomain"; > diff --git a/arch/arm/boot/dts/omap36xx.dtsi > b/arch/arm/boot/dts/omap36xx.dtsi > index 7e8dee9175d6..5e1bcd06a996 100644 > --- a/arch/arm/boot/dts/omap36xx.dtsi > +++ b/arch/arm/boot/dts/omap36xx.dtsi > @@ -52,7 +52,7 @@ > }; > }; > > -/include/ "omap36xx-clocks.dtsi" > /include/ "omap34xx-omap36xx-clocks.dtsi" > /include/ "omap36xx-omap3430es2plus-clocks.dtsi" > /include/ "omap36xx-am35xx-omap3430es2plus-clocks.dtsi" > +/include/ "omap36xx-clocks.dtsi" > -- > 1.8.3.2 > > > BR, marek -- as simple and primitive as possible ------------------------------------------------- Marek Belisko - OPEN-NANDRA Freelance Developer Ruska Nova Ves 219 | Presov, 08005 Slovak Republic Tel: +421 915 052 184 skype: marekwhite twitter: #opennandra web: http://open-nandra.com -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html