Re: [PATCH v3 3/5] platform/x86: asus-armoury: add apu-mem control support

[Luke Jones]

On Thu, 19 Sep 2024, at 3:44 AM, Mario Limonciello wrote:
> On 9/18/2024 04:42, Luke D. Jones wrote:
> > 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@xxxxxxxxxx>
> > ---
> >   drivers/platform/x86/asus-armoury.c        | 114 +++++++++++++++++++++
> >   include/linux/platform_data/x86/asus-wmi.h |   1 +
> >   2 files changed, 115 insertions(+)
> > 
> > diff --git a/drivers/platform/x86/asus-armoury.c b/drivers/platform/x86/asus-armoury.c
> > index 176ab5f105dd..b276c42f98d8 100644
> > --- a/drivers/platform/x86/asus-armoury.c
> > +++ b/drivers/platform/x86/asus-armoury.c
> > @@ -456,6 +456,119 @@ 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 256:
> > + mem = 0;
> > + break;
> > + case 258:
> > + mem = 1;
> > + break;
> > + case 259:
> > + mem = 2;
> > + break;
> > + case 260:
> > + mem = 3;
> > + break;
> > + case 261:
> > + mem = 4;
> > + break;
> > + case 262:
> > + /* This is out of order and looks wrong but is correct */
> > + mem = 8;
> > + break;
> > + case 263:
> > + mem = 5;
> > + break;
> > + case 264:
> > + mem = 6;
> > + break;
> > + case 265:
> > + 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 = 0;
> > + break;
> > + case 1:
> > + mem = 258;
> > + break;
> > + case 2:
> > + mem = 259;
> > + break;
> > + case 3:
> > + mem = 260;
> > + break;
> > + case 4:
> > + mem = 261;
> > + break;
> > + case 5:
> > + mem = 263;
> > + break;
> > + case 6:
> > + mem = 264;
> > + break;
> > + case 7:
> > + mem = 265;
> > + break;
> > + case 8:
> > + /* This is out of order and looks wrong but is correct */
> > + mem = 262;
> > + break;
> > + default:
> > + return -EIO;
> > + }
> > +
> > + 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);
> 
> This doesn't seem right.  If you requested "0", you just set APU memory 
> to 0GB?

Yep.. I know it seems wrong but it's true. GHelper on windows does the same thing https://github.com/seerge/g-helper/blob/ab08bd8ab45774b3e1961ddff69b6281a2f6e733/app/AsusACPI.cs#L666

> > + 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");
> 
> What exactly is the unit for 0-8?  It's obviously not a a multiple of 
> base memory, is it a multiple of an adder?
> 
> Is this changing the VRAM allocation?  Like does 0 mean 256MB, 1 is 512 etc?

There is a log entry above that clarifying it but I thought I'd done the same here. Fixed now.
 
> > +}
> > +ATTR_GROUP_ENUM_CUSTOM(apu_mem, "apu_mem", "Set the available system memory for the APU to use");
> > +
> >   /* Simple attribute creation */
> >   ATTR_GROUP_ROG_TUNABLE(ppt_pl1_spl, "ppt_pl1_spl", ASUS_WMI_DEVID_PPT_PL1_SPL, cpu_default,
> >          cpu_min, cpu_max, 1, "Set the CPU slow package limit");
> > @@ -511,6 +624,7 @@ static const struct asus_attr_group armoury_attr_groups[] = {
> >   { &nv_temp_target_attr_group, ASUS_WMI_DEVID_NV_THERM_TARGET },
> >   { &dgpu_base_tgp_attr_group, ASUS_WMI_DEVID_DGPU_BASE_TGP },
> >   { &dgpu_tgp_attr_group, ASUS_WMI_DEVID_DGPU_SET_TGP },
> > + { &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 86629e621c61..e1aeafdf05d5 100644
> > --- a/include/linux/platform_data/x86/asus-wmi.h
> > +++ b/include/linux/platform_data/x86/asus-wmi.h
> > @@ -136,6 +136,7 @@
> >   
> >   #define ASUS_WMI_DEVID_DGPU_BASE_TGP 0x00120099
> >   #define ASUS_WMI_DEVID_DGPU_SET_TGP 0x00120098
> > +#define ASUS_WMI_DEVID_APU_MEM 0x000600C1
> >   
> >   /* gpu mux switch, 0 = dGPU, 1 = Optimus */
> >   #define ASUS_WMI_DEVID_GPU_MUX 0x00090016
> 
>