Hi Daniel, On 15 May 2018 at 18:27, Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> wrote: > On Mon, May 14, 2018 at 04:55:26PM +0800, Baolin Wang wrote: >> Hi, >> >> We will meet below issues when compensating the suspend time for the timekeeping. >> >> 1. We have too many different ways of dealing with persistent timekeeping >> across architectures, so it is hard for one driver to compatable with different >> architectures. >> >> 2. On some platforms (such as Spreadtrum platform), we registered the high >> resolution timer as one clocksource to update the OS time, but the high >> resolution timer will be stopped in suspend state. So we use another one >> always-on timer (but low resolution) to calculate the suspend time to >> compensate the OS time. Though we can register the always-on timer as one >> clocksource, we need re-calculate the mult/shift with one larger conversion >> range to calculate the suspend time and need update the clock in case of >> running over the always-on timer. > > First, can you elaborate what you mean by 'suspend state' ? On which power What I mean is the high resolution timer will be stopped when the system goes into suspend state. > domain the clocksource belongs to? On Spreadtrum platform, It belongs to one power domain named "APCPU_TOP", that will be power down when the system goes into suspend state. -- Baolin.wang Best Regards -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
