Re: [PATCH v8 4/8] platform/x86: asus-armoury: add apu-mem control support

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

On Wed, 19 Mar 2025, Luke Jones wrote:

> From: "Luke D. Jones" <luke@ljones.dev>
> 
> Implement the APU memory size control under the asus-armoury module using
> the fw_attributes class.
> 
> This allows the APU allocated memory size to be adjusted depending on
> the users priority. A reboot is required after change.
> 
> Signed-off-by: Luke D. Jones <luke@ljones.dev>
> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
> ---
>  drivers/platform/x86/asus-armoury.c        | 114 +++++++++++++++++++++
>  include/linux/platform_data/x86/asus-wmi.h |   2 +
>  2 files changed, 116 insertions(+)
> 
> diff --git a/drivers/platform/x86/asus-armoury.c b/drivers/platform/x86/asus-armoury.c
> index a299471d78d5..b1d6b0c41669 100644
> --- a/drivers/platform/x86/asus-armoury.c
> +++ b/drivers/platform/x86/asus-armoury.c
> @@ -388,6 +388,119 @@ static ssize_t egpu_enable_current_value_store(struct kobject *kobj, struct kobj
>  WMI_SHOW_INT(egpu_enable_current_value, "%d\n", ASUS_WMI_DEVID_EGPU);
>  ATTR_GROUP_BOOL_CUSTOM(egpu_enable, "egpu_enable", "Enable the eGPU (also disables dGPU)");
>  
> +/* Device memory available to APU */
> +
> +static ssize_t apu_mem_current_value_show(struct kobject *kobj, struct kobj_attribute *attr,
> +					  char *buf)
> +{
> +	int err;
> +	u32 mem;
> +
> +	err = asus_wmi_get_devstate_dsts(ASUS_WMI_DEVID_APU_MEM, &mem);
> +	if (err)
> +		return err;
> +
> +	switch (mem) {
> +	case 0x100:
> +		mem = 0;
> +		break;
> +	case 0x102:
> +		mem = 1;
> +		break;
> +	case 0x103:
> +		mem = 2;
> +		break;
> +	case 0x104:
> +		mem = 3;
> +		break;
> +	case 0x105:
> +		mem = 4;
> +		break;
> +	case 0x106:
> +		/* This is out of order and looks wrong but is correct */
> +		mem = 8;
> +		break;
> +	case 0x107:
> +		mem = 5;
> +		break;
> +	case 0x108:
> +		mem = 6;
> +		break;
> +	case 0x109:
> +		mem = 7;
> +		break;
> +	default:
> +		mem = 4;
> +		break;
> +	}
> +
> +	return sysfs_emit(buf, "%u\n", mem);
> +}
> +
> +static ssize_t apu_mem_current_value_store(struct kobject *kobj, struct kobj_attribute *attr,
> +					   const char *buf, size_t count)
> +{
> +	int result, err;
> +	u32 requested, mem;
> +
> +	result = kstrtou32(buf, 10, &requested);
> +	if (result)
> +		return result;
> +
> +	switch (requested) {
> +	case 0:
> +		mem = 0x000;
> +		break;
> +	case 1:
> +		mem = 0x102;
> +		break;
> +	case 2:
> +		mem = 0x103;
> +		break;
> +	case 3:
> +		mem = 0x104;
> +		break;
> +	case 4:
> +		mem = 0x105;
> +		break;
> +	case 5:
> +		mem = 0x107;
> +		break;
> +	case 6:
> +		mem = 0x108;
> +		break;
> +	case 7:
> +		mem = 0x109;
> +		break;
> +	case 8:
> +		/* This is out of order and looks wrong but is correct */
> +		mem = 0x106;
> +		break;
> +	default:
> +		return -EIO;
> +	}

Should these switch/cases be just replaced with an array (and loop in one 
of the functions).

> +
> +	err = asus_wmi_set_devstate(ASUS_WMI_DEVID_APU_MEM, mem, &result);
> +	if (err) {
> +		pr_warn("Failed to set apu_mem: %d\n", err);
> +		return err;
> +	}
> +
> +	pr_info("APU memory changed to %uGB, reboot required\n", requested);
> +	sysfs_notify(kobj, NULL, attr->attr.name);
> +
> +	asus_set_reboot_and_signal_event();
> +
> +	return count;
> +}
> +
> +static ssize_t apu_mem_possible_values_show(struct kobject *kobj, struct kobj_attribute *attr,
> +					    char *buf)
> +{
> +	return sysfs_emit(buf, "0;1;2;3;4;5;6;7;8\n");

I you add the array, would be useful to BUILD_BUG_ON() in this if the 
ARRAY_SIZE() differs.

> +}
> +ATTR_GROUP_ENUM_CUSTOM(apu_mem, "apu_mem", "Set available system RAM (in GB) for the APU to use");
> +
>  /* Simple attribute creation */
>  ATTR_GROUP_ENUM_INT_RO(charge_mode, "charge_mode", ASUS_WMI_DEVID_CHARGE_MODE, "0;1;2",
>  		       "Show the current mode of charging");
> @@ -408,6 +521,7 @@ static const struct asus_attr_group armoury_attr_groups[] = {
>  	{ &egpu_connected_attr_group, ASUS_WMI_DEVID_EGPU_CONNECTED },
>  	{ &egpu_enable_attr_group, ASUS_WMI_DEVID_EGPU },
>  	{ &dgpu_disable_attr_group, ASUS_WMI_DEVID_DGPU },
> +	{ &apu_mem_attr_group, ASUS_WMI_DEVID_APU_MEM },
>  
>  	{ &charge_mode_attr_group, ASUS_WMI_DEVID_CHARGE_MODE },
>  	{ &boot_sound_attr_group, ASUS_WMI_DEVID_BOOT_SOUND },
> diff --git a/include/linux/platform_data/x86/asus-wmi.h b/include/linux/platform_data/x86/asus-wmi.h
> index 62a9adb1af2f..f3494a9efea7 100644
> --- a/include/linux/platform_data/x86/asus-wmi.h
> +++ b/include/linux/platform_data/x86/asus-wmi.h
> @@ -137,6 +137,8 @@
>  /* dgpu on/off */
>  #define ASUS_WMI_DEVID_DGPU		0x00090020
>  
> +#define ASUS_WMI_DEVID_APU_MEM		0x000600C1
> +
>  /* gpu mux switch, 0 = dGPU, 1 = Optimus */
>  #define ASUS_WMI_DEVID_GPU_MUX		0x00090016
>  #define ASUS_WMI_DEVID_GPU_MUX_VIVO	0x00090026
> 

-- 
 i.