[linux-sunxi] Re: [PATCH] clk: sunxi-ng: sun6i-a31: Force AHB1 clock to use PLL6 as parent
On Tue, Oct 18, 2016 at 01:42:09PM +0800, Chen-Yu Tsai wrote:
> On the A31, the DMA engine only works if AHB1 is clocked from PLL6.
> In addition, the hstimer is clocked from AHB1, and if AHB1 is clocked
> from the CPU clock, and cpufreq is working, we get an unstable timer.
>
> Force the AHB1 clock to use PLL6 as its parent. Previously this was done
> in the device tree with the assigned-clocks and assigned-clocks-parent
> bindings. However with this new monolithic driver, the system critical
> clocks aren't exported through the device tree. The alternative is to
> force this setting in the driver before the clocks are registered.
>
> This is also done in newer versions of mainline U-boot. But people still
> using an older version, or even the vendor version, can still hit this
> issue. Hence the need to do it in the kernel as well.
>
> Reported-by: Hans de Goede
> Reported-by: Maxime Ripard
> Fixes: c6e6c96d8fa6 ("clk: sunxi-ng: Add A31/A31s clocks")
> Signed-off-by: Chen-Yu Tsai
Applied, thanks!
Maxime
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Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
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[linux-sunxi] Re: [PATCH] clk: sunxi-ng: sun6i-a31: Force AHB1 clock to use PLL6 as parent
On Tue, Oct 18, 2016 at 3:50 PM, Jean-Francois Moine wrote: > On Tue, 18 Oct 2016 13:42:09 +0800 > Chen-Yu Tsai wrote: > >> On the A31, the DMA engine only works if AHB1 is clocked from PLL6. >> In addition, the hstimer is clocked from AHB1, and if AHB1 is clocked >> from the CPU clock, and cpufreq is working, we get an unstable timer. >> >> Force the AHB1 clock to use PLL6 as its parent. Previously this was done >> in the device tree with the assigned-clocks and assigned-clocks-parent >> bindings. However with this new monolithic driver, the system critical >> clocks aren't exported through the device tree. The alternative is to >> force this setting in the driver before the clocks are registered. > > It should be simpler to export the constant (CLK_AHB1) instead of > adding code... I get you. But the plan is to not export system core clocks that don't have a direct user. ChenYu -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[linux-sunxi] Re: [PATCH] clk: sunxi-ng: sun6i-a31: Force AHB1 clock to use PLL6 as parent
On Tue, 18 Oct 2016 13:42:09 +0800 Chen-Yu Tsai wrote: > On the A31, the DMA engine only works if AHB1 is clocked from PLL6. > In addition, the hstimer is clocked from AHB1, and if AHB1 is clocked > from the CPU clock, and cpufreq is working, we get an unstable timer. > > Force the AHB1 clock to use PLL6 as its parent. Previously this was done > in the device tree with the assigned-clocks and assigned-clocks-parent > bindings. However with this new monolithic driver, the system critical > clocks aren't exported through the device tree. The alternative is to > force this setting in the driver before the clocks are registered. It should be simpler to export the constant (CLK_AHB1) instead of adding code... -- Ken ar c'hentañ | ** Breizh ha Linux atav! ** Jef | http://moinejf.free.fr/ -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
