[PATCH 3/3] arm: mach-k3: am62a: Fixup a53 max cpu frequency by speed-grade

[Daniel Schultz]

On 4/30/25 12:42, Aparna Patra wrote:
> AM62A SoC has multiple speed grades. Add function to delete
> non-relevant CPU frequency nodes, based on the information
> retrieved from hardware registers. Fastest grade's maximum
> frequency also depends on PMIC voltage,hence to simplify
> implementation use the smaller value.
>
> Signed-off-by: Aparna Patra <a-patra at ti.com>
> ---
>   arch/arm/mach-k3/am62ax/am62a7_fdt.c          | 14 +++++++++++
>   .../arm/mach-k3/include/mach/am62a_hardware.h | 23 +++++++++++++++++++
>   2 files changed, 37 insertions(+)
>
> diff --git a/arch/arm/mach-k3/am62ax/am62a7_fdt.c b/arch/arm/mach-k3/am62ax/am62a7_fdt.c
> index 40833ca392..9526c5b255 100644
> --- a/arch/arm/mach-k3/am62ax/am62a7_fdt.c
> +++ b/arch/arm/mach-k3/am62ax/am62a7_fdt.c
> @@ -81,6 +81,19 @@ static void fdt_fixup_thermal_zone_nodes_am62a(void *blob, int maxc)
>   	}
>   }
>   
> +static void fdt_fixup_cpu_freq_nodes_am62a(void *blob, int max_freq)
> +{
> +	if (max_freq >= 1250000000)
> +		return;
I dont think this if case is required. Just let if fail both following 
conditions.
> +	if (max_freq <= 1000000000) {
> +		fdt_del_node_path(blob, "/opp-table/opp-1250000000");
> +		fdt_del_node_path(blob, "/opp-table/opp-1400000000");
> +	}
> +	if (max_freq <= 800000000) {
> +		fdt_del_node_path(blob, "/opp-table/opp-1000000000");
> +	}
> +}
> +
>   int ft_system_setup(void *blob, struct bd_info *bd)
>   {
>   	fdt_fixup_cores_wdt_nodes_am62a(blob, k3_get_core_nr());
> @@ -88,6 +101,7 @@ int ft_system_setup(void *blob, struct bd_info *bd)
>   	fdt_fixup_video_codec_nodes_am62a(blob, k3_has_video_codec());
>   	fdt_fixup_canfd_nodes_am62a(blob, k3_has_canfd());
>   	fdt_fixup_thermal_zone_nodes_am62a(blob, k3_get_max_temp());
> +	fdt_fixup_cpu_freq_nodes_am62a(blob, k3_get_a53_max_frequency());
>   	fdt_fixup_reserved(blob, "tfa", CONFIG_K3_ATF_LOAD_ADDR, 0x80000);
>   	fdt_fixup_reserved(blob, "optee", CONFIG_K3_OPTEE_LOAD_ADDR, 0x1800000);
>   
> diff --git a/arch/arm/mach-k3/include/mach/am62a_hardware.h b/arch/arm/mach-k3/include/mach/am62a_hardware.h
> index 0ec04a72f5..64e4a379fa 100644
> --- a/arch/arm/mach-k3/include/mach/am62a_hardware.h
> +++ b/arch/arm/mach-k3/include/mach/am62a_hardware.h
> @@ -28,6 +28,8 @@
>   #define JTAG_DEV_VIDEO_CODEC_SHIFT			14
>   #define JTAG_DEV_DSS_MASK			GENMASK(16, 13)
>   #define JTAG_DEV_DSS_SHIFT			13
> +#define JTAG_DEV_SPEED_MASK			GENMASK(10, 6)
> +#define JTAG_DEV_SPEED_SHIFT			6
>   #define JTAG_DEV_TEMP_MASK			GENMASK(5, 3)
>   #define JTAG_DEV_TEMP_SHIFT			3
>   
> @@ -144,6 +146,27 @@ static inline int k3_get_max_temp(void)
>   		return JTAG_DEV_TEMP_EXTENDED_VALUE;
>   }
>   
> +static inline char k3_get_speed_grade(void)
> +{
> +	u32 dev_id = readl(CTRLMMR_WKUP_JTAG_DEVICE_ID);
> +	u32 speed_grade = (dev_id & JTAG_DEV_SPEED_MASK) >>
> +			   JTAG_DEV_SPEED_SHIFT;
> +
> +	return 'A' - 1 + speed_grade;
> +}
> +
> +static inline int k3_get_a53_max_frequency(void)
> +{
> +	if (k3_get_speed_grade() <= 'N')
> +		return 800000000;
> +

^ empty lines where should be none in this function.

- Daniel

> +	else if (k3_get_speed_grade() <= 'R')
> +		return 1000000000;
> +
> +	else
> +		return 1250000000;
> +}
> +
>   #if defined(CONFIG_SYS_K3_SPL_ATF) && !defined(__ASSEMBLY__)
>   
>   static const u32 put_device_ids[] = {};