Hi Jon and Vinayak, On Tue, Jun 24, 2014 at 11:42 AM, Jon Masters <jcm@xxxxxxxxxx> wrote: > On 06/23/2014 10:47 PM, Ming Lei wrote: > >> On Thu, Mar 20, 2014 at 5:47 PM, Vinayak Kale <vkale@xxxxxxx> wrote: >>> This patch adds the PMU device tree node for APM X-Gene Storm SOC. >>> >>> Please note that this patch has dependancy on a GIC driver patch [1] which is >>> yet to be approved by maintainers. >>> >>> [1]- https://lkml.org/lkml/2014/2/27/605 >>> (irqchip:gic: change access of gicc_ctrl register to read modify write) > >> No matter if Feng Kan's gic patch is applied or not, perf(PMU) >> still can't work well with your patch, and the failure[1] will be >> triggered when 'perf top' is started. >> >> The failure happened during the 1st pmu overflow interrupt. >> >> I test several mustang boards, and all has the problem with >> upstream kernel. > > Note that the GIC bypass register config is set by the firmware and this > only preserves the original setting, so you could be running an older > firmware (such as U-Boot). On our (UEFI-enabled systems, complete with > correct patch) perf top runs correctly without any such problems. I am wondering if it is related with boot or firmware. We have a board which is running APM internal 3.12 based kernel, and perf(pmu) works well. But if I just replace the 3.12 based kernel with upstream kernel and keep others(boot, kernel parameter, fs, ....) not changed, then the problem still can happen. Thanks, -- Ming Lei -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
