On Thu, Jun 12, 2014 at 01:38:28PM -0600, Stephen Warren wrote: > On 06/12/2014 09:58 AM, Peter De Schrijver wrote: > > This patchset introduces support for Tegra's microsecond counter as the > > udelay() timer. This is useful on Tegra SoCs which do not have an arch timer > > such as Tegra20 and Tegra30. Using the microsecond counter instead of a delay > > based loop avoids potential problems during cpu frequency changes. > > > > The set consists of 3 patches: > > > > Patch 1 introduces a new call which is used by the ARM architecture delay > > timer code to prevent changing the delay timer after calibration is finished > > and thus can be in use. > > > > Patch 2 adds logic to choose the delay timer with the highest resolution. This > > allows the same registration code to be used on all Tegra SoCs and yet use the > > higher resolution arch timer when available (eg on Tegra114 or Tegra124). > > > > Patch 3 adds the actual delay timer code. > > > > Patch set has been verified on ventana (Tegra20), beaver (Tegra30), > > dalmore (Tegra114) and jetson TK1 (Tegra124). > > Russell, Paul, do patches 1 and 2 look good to you? If so, if you can > ack them, I'd be happy to queue this series in the Tegra git tree. If > that doesn't work for you, please let me know who will apply these > patches. Thanks. When I saw them, I did have a question in the back of my mind about the interlocking - whether we should just mandate that these are always registered before delay calibration. Then I remember the mess that platforms made of the sched_clock() stuff. So, I don't see any other way to ensure that platforms do the right thing other than providing that kind of stick... so I guess we'll have to have them. Acked-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> -- FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly improving, and getting towards what was expected from it. -- 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
