On Wed, Aug 23, 2017 at 05:20:55PM +0200, Geert Uytterhoeven wrote: > Hi Simon, > > On Mon, Aug 21, 2017 at 3:01 PM, Simon Horman > <horms+renesas@xxxxxxxxxxxx> wrote: > > this patch-set adds Z and Z2 clock support. > > > > These are dependencies for supporting CPUFreq. The remainder of that > > work is being posted separately and can be found at: > > > > https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas.git topic/rcar-gen3-cpufreq > > > > A description of steps taken to lightly exercise the same feature for the > > r88a7795 the above can be found at the link below. The results are the same > > for the r8a7796 with the exception that it has two active CPU cores rather > > than four. > > > > http://elinux.org/Tests:R-CAR-GEN3-CPUFreq > > Thanks for your patches, and the wiki page! > > I gave it a try on R-Car H3 (ES1.0 and ES2.0) and M3-W (ES1.0), and the > off-by-two factor of the Z clock frequency is gone. > I couldn't test on R-Car H3 ES1.1. Probably it's OK, too (ES1.1 fixed the > missing PLL0/2/4 post-divider in ES1.0). > > 1. After boot-up, the CPU clock frequency is 1.5 GHz, and > /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq and > /sys/kernel/debug/clk/z/clk_rate agree. Good. > > 2. After switching to the conservative governor, scaling_cur_freq reports > either a 500 MHz or 1 GHz clock rate. > But /sys/kernel/debug/clk/z/clk_rate disagrees: it reports either a 200 > or 700 MHz clock rate. > > Ah, there's also cpuinfo_cur_freq. That value matches the Z clock. > Interestingly, cpuinfo_cur_freq is lower than cpuinfo_min_freq? > /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq:200000 > /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq:1500000 > /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq:500000 > > 3. After switching back to the performance governor, scaling_cur_freq reports > 1.5 GHz again. > But cpuinfo_cur_freq is still only 700 MHz, just like z/clk_rate. > > Do you know what's wrong? Unfortunately not. I will look into this.
