On Tue, Feb 27, 2018 at 11:17:12AM +0100, Sebastian Reichel wrote: > Hi, > > On Tue, Feb 27, 2018 at 09:10:34AM +0800, Shawn Guo wrote: > > On Mon, Feb 26, 2018 at 02:47:41PM +0100, Sebastian Reichel wrote: > > > On Sat, Feb 24, 2018 at 03:45:44PM +0800, Shawn Guo wrote: > > > > On Mon, Feb 12, 2018 at 01:39:44PM +0100, Sebastian Reichel wrote: > > > > > On i.MX53 it is necessary to set the DBG_EN bit in the > > > > > platform GPC register to enable access to PMU counters > > > > > other than the cycle counter. > > > > > > > > > > Signed-off-by: Sebastian Reichel <sebastian.reic...@collabora.co.uk> > > > > > --- > > > > > arch/arm/mach-imx/mach-imx53.c | 39 > > > > > ++++++++++++++++++++++++++++++++++++++- > > > > > 1 file changed, 38 insertions(+), 1 deletion(-) > > > > > > > > > > diff --git a/arch/arm/mach-imx/mach-imx53.c > > > > > b/arch/arm/mach-imx/mach-imx53.c > > > > > index 07c2e8dca494..658e28604dca 100644 > > > > > --- a/arch/arm/mach-imx/mach-imx53.c > > > > > +++ b/arch/arm/mach-imx/mach-imx53.c > > > > > @@ -28,10 +28,47 @@ static void __init imx53_init_early(void) > > > > > mxc_set_cpu_type(MXC_CPU_MX53); > > > > > } > > > > > > > > > > +#define MXC_CORTEXA8_PLAT_GPC 0x63fa0004 > > > > > > > > The base address should be retrieved from device tree. > > > > > > DT has no entry for 0x63fa0000-0x63fa3fff. iMX53 TRM lists it as "ARM > > > Platform" > > > with 8 platform specific 32 bit registers. Do you think it's worth the > > > trouble > > > adding a new binding? Do you have a suggestion for a compatible value? > > > > Looking at it more closely, I feel that patching every single platform > > which needs to set up additional register for secure-reg-access support > > doesn't really scale. Can we have pmu driver do it with a phandle in > > DT pointing to the register and bit that need to be configured? > > The PMU driver used to have a feature for initialising platform > specific bits, but it is currently being removed to make the PMU > code more maintainable. My understanding is, that it's very uncommon > to require platform specific setup to get secure-reg-access working. > I.e. it is not needed for newer iMX platforms.
Are you saying this is a very specific setup required by i.MX53 only? In that case, I can live with it. Shawn
