Re: [PATCH V2 7/7] perf/x86/intel/uncore: Implement global init callback for GNR uncore

["Mi, Dapeng" <dapeng1.mi@linux.intel.com>]

On 5/27/2026 11:11 PM, Zide Chen wrote:
> On Sierra Forest and Clearwater Forest, the FRZ_ALL bit in the global
> control register defaults to 0 at boot, but UBOX PMON units do not
> work until the global control register is explicitly written with 0
> to trigger hardware initialization properly.
>
> Implement the generic uncore_msr_global_init() callback and add it to
> gnr_uncore_init[], which is shared by GNR, GRR, SRF, and CWF.

Need a "Fixes" tag?

Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>


> Signed-off-by: Zide Chen <zide.chen@intel.com>
> ---
> V2:
> - Propagate return value of wrmsrq_on_cpu() to global_init().
> ---
>  arch/x86/events/intel/uncore.c           | 13 ++++++++++++-
>  arch/x86/events/intel/uncore.h           |  2 +-
>  arch/x86/events/intel/uncore_discovery.c |  2 +-
>  3 files changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/events/intel/uncore.c b/arch/x86/events/intel/uncore.c
> index 4b3a1fa5b41b..7857959c6e82 100644
> --- a/arch/x86/events/intel/uncore.c
> +++ b/arch/x86/events/intel/uncore.c
> @@ -1716,7 +1716,7 @@ static int __init uncore_mmio_init(void)
>  	return ret;
>  }
>  
> -static int uncore_mmio_global_init(u64 ctl)
> +static int uncore_mmio_global_init(int die, u64 ctl)
>  {
>  	void __iomem *io_addr;
>  
> @@ -1731,6 +1731,16 @@ static int uncore_mmio_global_init(u64 ctl)
>  	return 0;
>  }
>  
> +static int uncore_msr_global_init(int die, u64 msr)
> +{
> +	int cpu = uncore_die_to_cpu(die);
> +
> +	if (cpu == -1)
> +		return -ENODEV;
> +
> +	return wrmsrq_on_cpu(cpu, msr, 0);
> +}
> +
>  static const struct uncore_plat_init nhm_uncore_init __initconst = {
>  	.cpu_init = nhm_uncore_cpu_init,
>  };
> @@ -1871,6 +1881,7 @@ static const struct uncore_plat_init gnr_uncore_init __initconst = {
>  	.domain[0].base_is_pci = true,
>  	.domain[0].discovery_base = UNCORE_DISCOVERY_TABLE_DEVICE,
>  	.domain[0].units_ignore = gnr_uncore_units_ignore,
> +	.domain[0].global_init = uncore_msr_global_init,
>  };
>  
>  static const struct uncore_plat_init dmr_uncore_init __initconst = {
> diff --git a/arch/x86/events/intel/uncore.h b/arch/x86/events/intel/uncore.h
> index 94c68e3417b6..c2e5ccb1d72c 100644
> --- a/arch/x86/events/intel/uncore.h
> +++ b/arch/x86/events/intel/uncore.h
> @@ -53,7 +53,7 @@ struct uncore_discovery_domain {
>  	/* MSR address or PCI device used as the discovery base */
>  	u32	discovery_base;
>  	bool	base_is_pci;
> -	int	(*global_init)(u64 ctl);
> +	int	(*global_init)(int die, u64 ctl);
>  
>  	/* The units in the discovery table should be ignored. */
>  	int	*units_ignore;
> diff --git a/arch/x86/events/intel/uncore_discovery.c b/arch/x86/events/intel/uncore_discovery.c
> index af2217b44a81..e36613d934b1 100644
> --- a/arch/x86/events/intel/uncore_discovery.c
> +++ b/arch/x86/events/intel/uncore_discovery.c
> @@ -287,7 +287,7 @@ static int __parse_discovery_table(struct uncore_discovery_domain *domain,
>  	if (!io_addr)
>  		return -ENOMEM;
>  
> -	if (domain->global_init && domain->global_init(global.ctl)) {
> +	if (domain->global_init && domain->global_init(die, global.ctl)) {
>  		ret = -ENODEV;
>  		goto out;
>  	}