On Thu, Nov 19, 2015 at 02:19:47PM +0000, Jon Hunter wrote: > Tegra support several low-power (LPx) states, which are: > - LP0: CPU + Core voltage off and DRAM in self-refresh > - LP1: CPU voltage off and DRAM in self-refresh > - LP2: CPU voltage off > > When entering any of the above states the tegra_disable_clean_inv_dcache() > function is called to flush the dcache. The function > tegra_disable_clean_inv_dcache() will either flush the entire data cache or > up to the Level of Unification Inner Shareable (LoUIS) depending on the > value in r0. When tegra_disable_clean_inv_dcache() is called by > tegra20_sleep_core_finish() or tegra30_sleep_core_finish(), to enter LP0 > and LP1 power state, the r0 register contains a physical memory address > which will not be equal to TEGRA_FLUSH_CACHE_ALL (1) and so the data cache > will be only flushed to the LoUIS. However, when > tegra_disable_clean_inv_dcache() called by tegra_sleep_cpu_finish() to > enter to LP2 power state, r0 is set to TEGRA_FLUSH_CACHE_ALL to flush the > entire dcache. > > Please note that tegra20_sleep_core_finish(), tegra30_sleep_core_finish() > and tegra_sleep_cpu_finish() are called by the boot CPU once all other CPUs > have been disabled and so it seems appropriate to flush the entire cache at > this stage. > > Therefore, ensure that r0 is set to TEGRA_FLUSH_CACHE_ALL when calling > tegra_disable_clean_inv_dcache() from tegra20_sleep_core_finish() and > tegra30_sleep_core_finish(). > > Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx> > --- > > Please note that I have not encountered any problems without this change > so far, but I noticed this from reviewing the suspend sequence. I have > tested this on tegra20, tegra30, tegra114 and tegra124 and verified that > suspend/resume to LP1 is working fine. > > arch/arm/mach-tegra/sleep-tegra20.S | 3 +++ > arch/arm/mach-tegra/sleep-tegra30.S | 3 +++ > 2 files changed, 6 insertions(+) Applied, thanks. Thierry
Attachment:
signature.asc
Description: PGP signature
