On 5/27/2024 8:36 PM, Luke D. Jones wrote:
Exposes the APU memory setting available on a few ASUS models such as
the ROG Ally.
Signed-off-by: Luke D. Jones <luke@xxxxxxxxxx>
---
.../ABI/testing/sysfs-platform-asus-wmi | 8 ++
drivers/platform/x86/asus-wmi.c | 109 ++++++++++++++++++
include/linux/platform_data/x86/asus-wmi.h | 3 +
3 files changed, 120 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-platform-asus-wmi b/Documentation/ABI/testing/sysfs-platform-asus-wmi
index ac881e72e374..d221a3bc1a81 100644
--- a/Documentation/ABI/testing/sysfs-platform-asus-wmi
+++ b/Documentation/ABI/testing/sysfs-platform-asus-wmi
@@ -245,3 +245,11 @@ Description:
Show the maximum performance and efficiency core countin format
0x[E][P] where [E] is the efficiency core count, and [P] is
the perfromance core count.
+
+What: /sys/devices/platform/<platform>/apu_mem
+Date: Jun 2024
+KernelVersion: 6.11
+Contact: "Luke Jones" <luke@xxxxxxxxxx>
+Description:
+ Set the maximum available system memory for the APU.
+ * Min=0, Max=8
What is the unit? It seems like multiples of something?
diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index f62a36dfcd4b..4b5fbae8c563 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -855,6 +855,112 @@ static DEVICE_ATTR_RW(cores_enabled);
WMI_SIMPLE_SHOW(cores_max, "0x%x\n", ASUS_WMI_DEVID_CORES_MAX);
static DEVICE_ATTR_RO(cores_max);
+/* Device memory available to APU */
+
+static ssize_t apu_mem_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct asus_wmi *asus = dev_get_drvdata(dev);
+ int err;
+ u32 mem;
+
+ err = asus_wmi_get_devstate(asus, ASUS_WMI_DEVID_APU_MEM, &mem);
+ if (err < 0)
+ 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:
+ 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, "%d\n", mem);
+}
+
+static ssize_t apu_mem_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct asus_wmi *asus = dev_get_drvdata(dev);
+ int result, err;
+ u32 mem;
+
+ result = kstrtou32(buf, 10, &mem);
+ if (result)
+ return result;
+
+ switch (mem) {
+ 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:
+ mem = 262;
Is case 8 a mistake, or intentionally out of order?
+ 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, reboot required\n");
If you're logging something into the logs for this, I'd say make it more
useful.
"APU memory changed to %d MB"
+ sysfs_notify(&asus->platform_device->dev.kobj, NULL, "apu_mem");
So this is a case that the BIOS attributes API I mentioned before would
be REALLY useful. There is a pending_reboot sysfs file that userspace
can query to know if a given setting requires a reboot or not.
Fwupd also uses this attribute to know to delay BIOS updates until the
system has been rebooted.
+
+ return count;
+}
+static DEVICE_ATTR_RW(apu_mem);
+
/* Tablet mode ****************************************************************/
static void asus_wmi_tablet_mode_get_state(struct asus_wmi *asus)
@@ -4100,6 +4206,7 @@ static struct attribute *platform_attributes[] = {
&dev_attr_panel_fhd.attr,
&dev_attr_cores_enabled.attr,
&dev_attr_cores_max.attr,
+ &dev_attr_apu_mem.attr,
&dev_attr_mini_led_mode.attr,
&dev_attr_available_mini_led_mode.attr,
NULL
@@ -4176,6 +4283,8 @@ static umode_t asus_sysfs_is_visible(struct kobject *kobj,
else if (attr == &dev_attr_cores_enabled.attr
|| attr == &dev_attr_cores_max.attr)
ok = asus_wmi_dev_is_present(asus, ASUS_WMI_DEVID_CORES_SET);
+ else if (attr == &dev_attr_apu_mem.attr)
+ ok = asus_wmi_dev_is_present(asus, ASUS_WMI_DEVID_APU_MEM);
else if (attr == &dev_attr_mini_led_mode.attr)
ok = asus->mini_led_dev_id != 0;
else if (attr == &dev_attr_available_mini_led_mode.attr)
diff --git a/include/linux/platform_data/x86/asus-wmi.h b/include/linux/platform_data/x86/asus-wmi.h
index 5a56e7e97785..efe608861e55 100644
--- a/include/linux/platform_data/x86/asus-wmi.h
+++ b/include/linux/platform_data/x86/asus-wmi.h
@@ -121,6 +121,9 @@
/* Maximum Intel E-core and P-core availability */
#define ASUS_WMI_DEVID_CORES_MAX 0x001200D3
+/* Set the memory available to the APU */
+#define ASUS_WMI_DEVID_APU_MEM 0x000600C1
+
/* MCU powersave mode */
#define ASUS_WMI_DEVID_MCU_POWERSAVE 0x001200E2
