31.05.2019 23:31, Daniel Lezcano пишет: > On 31/05/2019 14:33, Dmitry Osipenko wrote: >> 31.05.2019 11:26, Peter De Schrijver пишет: >>> On Fri, May 24, 2019 at 06:32:45PM +0300, Dmitry Osipenko wrote: >>>> Hello, >>>> >>>> This series primarily unifies the driver code across all Tegra SoC >>>> generations. In a result the clocksources are allocated per-CPU on >>>> older Tegra's and have a higher rating than the arch-timer, the newer >>>> Tegra210 is getting support for microsecond clocksource and the driver's >>>> code is getting much cleaner. Note that arch-timer usage is discouraged on >>>> all Tegra's due to the time jitter caused by the CPU frequency scaling. >>> >>> I think the limitations are more as follows: >>> >>> Chip timer suffers cpu dvfs jitter can wakeup from cc7 >>> T20 us-timer No Yes >>> T20 twd timer Yes No? >>> T30 us-timer No Yes >>> T30 twd timer Yes No? >>> T114 us-timer No Yes >>> T114 arch timer No Yes >>> T124 us-timer No Yes >>> T124 arch timer No Yes >>> T210 us-timer No Yes >>> T210 arch timer No No >>> T210 clk_m timer No Yes >>> >>> right? >> >> Doesn't arch timer run off the CPU clock? If yes (that's what I >> assumed), then it should be affected by the DVFS. Otherwise I'll lower >> the clocksource's rating for T114/124/132. >> >> TWD can't wake CPU from the power-down state, so it's a solid "No" for >> TWD in the "can wakeup from cc7" column. > > Wouldn't make sense to rename the timer-tegra20.c to timer-tegra.c now ? Wouldn't hurt, given the refreshment that driver is getting lately. I'll include a patch for that in the next revision, thanks.
