[PATCH v2 2/3] [ARM] perfevents: Add support for Scorpion performance monitors
Will Deacon
will.deacon at arm.com
Tue Mar 8 09:52:37 EST 2011
Hello Sheetal,
On Mon, 2011-03-07 at 21:47 +0000, Sheetal Sahasrabudhe wrote:
> This commit adds support for performance monitors provided by
> Qualcomm Scorpion and ScorpionMP processor to perfevents.
>
> Signed-off-by: Sheetal Sahasrabudhe <sheetals at codeaurora.org>
> Reviewed-by: Jean Pihet <j-pihet at ti.com>
> Reviewed-by: Will Deacon <will.deacon at arm.com>
> ---
> arch/arm/include/asm/perf_event.h | 2 +
> arch/arm/kernel/perf_event.c | 11 +
> arch/arm/kernel/perf_event_msm.c | 665 +++++++++++++++++++++++++++++++++++++
> 3 files changed, 678 insertions(+), 0 deletions(-)
> create mode 100644 arch/arm/kernel/perf_event_msm.c
>
[...]
> +static DEFINE_PER_CPU(u32, venum_orig_val);
> +static DEFINE_PER_CPU(u32, fp_orig_val);
> +
> +static void scorpion_pre_vlpm(void)
> +{
> + u32 venum_new_val;
> + u32 fp_new_val;
> + /* CPACR Enable CP10 access*/
> + asm volatile("mrc p15, 0, %0, c1, c0, 2" : "=r" (venum_orig_val));
> + venum_new_val = venum_orig_val | 0x00100000;
> + asm volatile("mcr p15, 0, %0, c1, c0, 2" : : "r" (venum_new_val));
> + isb();
> + /* Enable FPEXC */
> + fp_orig_val = fmrx(FPEXC);
> + fp_new_val = fp_orig_val | FPEXC_EN;
> + fmxr(FPEXC, fp_new_val);
> +}
> +
When I looked at this originally, I thought it would be nice to have
some functions or macros for poking with the CPACR and planned to submit
that as a separate patch...
... well it turns out we already have this! Please can you update this
bit of code to use the {get,set}_copro_access functions in asm/system.h?
You can use the CPACC_SVC macro to generate the access mask too instead
of hardcoding the 0x00100000.
Cheers,
Will
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