drm/nouveau/mxm: implement _DSM shadow method

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/nouveau_mxm.c b/drivers/gpu/drm/nouveau/nouveau_mxm.c
index f6f7356..840c88f 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_mxm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_mxm.c
@@ -476,11 +476,68 @@ mxm_shadow_rom(struct drm_device *dev, u8 version)
        return false;
 }
 
+#if defined(CONFIG_ACPI)
 static bool
 mxm_shadow_dsm(struct drm_device *dev, u8 version)
 {
-       return false;
+       struct drm_nouveau_private *dev_priv = dev->dev_private;
+       static char muid[] = {
+               0x00, 0xA4, 0x04, 0x40, 0x7D, 0x91, 0xF2, 0x4C,
+               0xB8, 0x9C, 0x79, 0xB6, 0x2F, 0xD5, 0x56, 0x65
+       };
+       u32 mxms_args[] = { 0x00000000 };
+       union acpi_object args[4] = {
+               /* _DSM MUID */
+               { .buffer.type = 3,
+                 .buffer.length = sizeof(muid),
+                 .buffer.pointer = muid,
+               },
+               /* spec says this can be zero to mean "highest revision", but
+                * of course there's at least one bios out there which fails
+                * unless you pass in exactly the version it supports..
+                */
+               { .integer.type = ACPI_TYPE_INTEGER,
+                 .integer.value = (version & 0xf0) << 4 | (version & 0x0f),
+               },
+               /* MXMS function */
+               { .integer.type = ACPI_TYPE_INTEGER,
+                 .integer.value = 0x00000010,
+               },
+               /* Pointer to MXMS arguments */
+               { .buffer.type = ACPI_TYPE_BUFFER,
+                 .buffer.length = sizeof(mxms_args),
+                 .buffer.pointer = (char *)mxms_args,
+               },
+       };
+       struct acpi_object_list list = { ARRAY_SIZE(args), args };
+       struct acpi_buffer retn = { ACPI_ALLOCATE_BUFFER, NULL };
+       union acpi_object *obj;
+       acpi_handle handle;
+       int ret;
+
+       handle = DEVICE_ACPI_HANDLE(&dev->pdev->dev);
+       if (!handle)
+               return false;
+
+       ret = acpi_evaluate_object(handle, "_DSM", &list, &retn);
+       if (ret) {
+               MXM_DBG(dev, "DSM MXMS failed: %d\n", ret);
+               return false;
+       }
+
+       obj = retn.pointer;
+       if (obj->type == ACPI_TYPE_BUFFER) {
+               dev_priv->mxms = kmemdup(obj->buffer.pointer,
+                                        obj->buffer.length, GFP_KERNEL);
+       } else
+       if (obj->type == ACPI_TYPE_INTEGER) {
+               MXM_DBG(dev, "DSM MXMS returned 0x%llx\n", obj->integer.value);
+       }
+
+       kfree(obj);
+       return dev_priv->mxms != NULL;
 }
+#endif
 
 #if defined(CONFIG_ACPI_WMI) || defined(CONFIG_ACPI_WMI_MODULE)
 
@@ -521,7 +578,9 @@ struct mxm_shadow_h {
        bool (*exec)(struct drm_device *, u8 version);
 } _mxm_shadow[] = {
        { "ROM", mxm_shadow_rom },
+#if defined(CONFIG_ACPI)
        { "DSM", mxm_shadow_dsm },
+#endif
 #if defined(CONFIG_ACPI_WMI) || defined(CONFIG_ACPI_WMI_MODULE)
        { "WMI", mxm_shadow_wmi },
 #endif