1 files changed, 68 insertions, 37 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_acpi.c b/drivers/gpu/drm/nouveau/nouveau_acpi.c
index db76b94e6e26..f2ad17aa33f0 100644
--- a/drivers/gpu/drm/nouveau/nouveau_acpi.c
+++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c
@@ -45,6 +45,8 @@
 static struct nouveau_dsm_priv {
         bool dsm_detected;
         bool optimus_detected;
+        bool optimus_flags_detected;
+        bool optimus_skip_dsm;
         acpi_handle dhandle;
         acpi_handle rom_handle;
 } nouveau_dsm_priv;
@@ -57,9 +59,6 @@ bool nouveau_is_v1_dsm(void) {
         return nouveau_dsm_priv.dsm_detected;
 }
 
-#define NOUVEAU_DSM_HAS_MUX 0x1
-#define NOUVEAU_DSM_HAS_OPT 0x2
-
 #ifdef CONFIG_VGA_SWITCHEROO
 static const char nouveau_dsm_muid[] = {
         0xA0, 0xA0, 0x95, 0x9D, 0x60, 0x00, 0x48, 0x4D,
@@ -110,7 +109,7 @@ static int nouveau_optimus_dsm(acpi_handle handle, int func, int arg, uint32_t *
  * requirements on the fourth parameter, so a private implementation
  * instead of using acpi_check_dsm().
  */
-static int nouveau_check_optimus_dsm(acpi_handle handle)
+static int nouveau_dsm_get_optimus_functions(acpi_handle handle)
 {
         int result;
 
@@ -125,7 +124,9 @@ static int nouveau_check_optimus_dsm(acpi_handle handle)
          * ACPI Spec v4 9.14.1: if bit 0 is zero, no function is supported.
          * If the n-th bit is enabled, function n is supported
          */
-        return result & 1 && result & (1 << NOUVEAU_DSM_OPTIMUS_CAPS);
+        if (result & 1 && result & (1 << NOUVEAU_DSM_OPTIMUS_CAPS))
+                return result;
+        return 0;
 }
 
 static int nouveau_dsm(acpi_handle handle, int func, int arg)
@@ -212,26 +213,55 @@ static const struct vga_switcheroo_handler nouveau_dsm_handler = {
         .get_client_id = nouveau_dsm_get_client_id,
 };
 
-static int nouveau_dsm_pci_probe(struct pci_dev *pdev)
+/*
+ * Firmware supporting Windows 8 or later do not use _DSM to put the device into
+ * D3cold, they instead rely on disabling power resources on the parent.
+ */
+static bool nouveau_pr3_present(struct pci_dev *pdev)
+{
+        struct pci_dev *parent_pdev = pci_upstream_bridge(pdev);
+        struct acpi_device *parent_adev;
+
+        if (!parent_pdev)
+                return false;
+
+        parent_adev = ACPI_COMPANION(&parent_pdev->dev);
+        if (!parent_adev)
+                return false;
+
+        return acpi_has_method(parent_adev->handle, "_PR3");
+}
+
+static void nouveau_dsm_pci_probe(struct pci_dev *pdev, acpi_handle *dhandle_out,
+                                  bool *has_mux, bool *has_opt,
+                                  bool *has_opt_flags, bool *has_pr3)
 {
         acpi_handle dhandle;
-        int retval = 0;
+        bool supports_mux;
+        int optimus_funcs;
 
         dhandle = ACPI_HANDLE(&pdev->dev);
         if (!dhandle)
-                return false;
+                return;
 
         if (!acpi_has_method(dhandle, "_DSM"))
-                return false;
+                return;
+
+        supports_mux = acpi_check_dsm(dhandle, nouveau_dsm_muid, 0x00000102,
+                                      1 << NOUVEAU_DSM_POWER);
+        optimus_funcs = nouveau_dsm_get_optimus_functions(dhandle);
 
-        if (acpi_check_dsm(dhandle, nouveau_dsm_muid, 0x00000102,
-                           1 << NOUVEAU_DSM_POWER))
-                retval |= NOUVEAU_DSM_HAS_MUX;
+        /* Does not look like a Nvidia device. */
+        if (!supports_mux && !optimus_funcs)
+                return;
 
-        if (nouveau_check_optimus_dsm(dhandle))
-                retval |= NOUVEAU_DSM_HAS_OPT;
+        *dhandle_out = dhandle;
+        *has_mux = supports_mux;
+        *has_opt = !!optimus_funcs;
+        *has_opt_flags = optimus_funcs & (1 << NOUVEAU_DSM_OPTIMUS_FLAGS);
+        *has_pr3 = false;
 
-        if (retval & NOUVEAU_DSM_HAS_OPT) {
+        if (optimus_funcs) {
                 uint32_t result;
                 nouveau_optimus_dsm(dhandle, NOUVEAU_DSM_OPTIMUS_CAPS, 0,
                                     &result);
@@ -239,11 +269,9 @@ static int nouveau_dsm_pci_probe(struct pci_dev *pdev)
                          (result & OPTIMUS_ENABLED) ? "enabled" : "disabled",
                          (result & OPTIMUS_DYNAMIC_PWR_CAP) ? "dynamic power, " : "",
                          (result & OPTIMUS_HDA_CODEC_MASK) ? "hda bios codec supported" : "");
-        }
-        if (retval)
-                nouveau_dsm_priv.dhandle = dhandle;
 
-        return retval;
+                *has_pr3 = nouveau_pr3_present(pdev);
+        }
 }
 
 static bool nouveau_dsm_detect(void)
@@ -251,11 +279,13 @@ static bool nouveau_dsm_detect(void)
         char acpi_method_name[255] = { 0 };
         struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
         struct pci_dev *pdev = NULL;
-        int has_dsm = 0;
-        int has_optimus = 0;
+        acpi_handle dhandle = NULL;
+        bool has_mux = false;
+        bool has_optimus = false;
+        bool has_optimus_flags = false;
+        bool has_power_resources = false;
         int vga_count = 0;
         bool guid_valid;
-        int retval;
         bool ret = false;
 
         /* lookup the MXM GUID */
@@ -268,32 +298,32 @@ static bool nouveau_dsm_detect(void)
         while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
                 vga_count++;
 
-                retval = nouveau_dsm_pci_probe(pdev);
-                if (retval & NOUVEAU_DSM_HAS_MUX)
-                        has_dsm |= 1;
-                if (retval & NOUVEAU_DSM_HAS_OPT)
-                        has_optimus = 1;
+                nouveau_dsm_pci_probe(pdev, &dhandle, &has_mux, &has_optimus,
+                                      &has_optimus_flags, &has_power_resources);
         }
 
         while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_3D << 8, pdev)) != NULL) {
                 vga_count++;
 
-                retval = nouveau_dsm_pci_probe(pdev);
-                if (retval & NOUVEAU_DSM_HAS_MUX)
-                        has_dsm |= 1;
-                if (retval & NOUVEAU_DSM_HAS_OPT)
-                        has_optimus = 1;
+                nouveau_dsm_pci_probe(pdev, &dhandle, &has_mux, &has_optimus,
+                                      &has_optimus_flags, &has_power_resources);
         }
 
         /* find the optimus DSM or the old v1 DSM */
-        if (has_optimus == 1) {
+        if (has_optimus) {
+                nouveau_dsm_priv.dhandle = dhandle;
                 acpi_get_name(nouveau_dsm_priv.dhandle, ACPI_FULL_PATHNAME,
                         &buffer);
                 printk(KERN_INFO "VGA switcheroo: detected Optimus DSM method %s handle\n",
                         acpi_method_name);
+                if (has_power_resources)
+                        pr_info("nouveau: detected PR support, will not use DSM\n");
                 nouveau_dsm_priv.optimus_detected = true;
+                nouveau_dsm_priv.optimus_flags_detected = has_optimus_flags;
+                nouveau_dsm_priv.optimus_skip_dsm = has_power_resources;
                 ret = true;
-        } else if (vga_count == 2 && has_dsm && guid_valid) {
+        } else if (vga_count == 2 && has_mux && guid_valid) {
+                nouveau_dsm_priv.dhandle = dhandle;
                 acpi_get_name(nouveau_dsm_priv.dhandle, ACPI_FULL_PATHNAME,
                         &buffer);
                 printk(KERN_INFO "VGA switcheroo: detected DSM switching method %s handle\n",
@@ -321,11 +351,12 @@ void nouveau_register_dsm_handler(void)
 void nouveau_switcheroo_optimus_dsm(void)
 {
         u32 result = 0;
-        if (!nouveau_dsm_priv.optimus_detected)
+        if (!nouveau_dsm_priv.optimus_detected || nouveau_dsm_priv.optimus_skip_dsm)
                 return;
 
-        nouveau_optimus_dsm(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_OPTIMUS_FLAGS,
-                            0x3, &result);
+        if (nouveau_dsm_priv.optimus_flags_detected)
+                nouveau_optimus_dsm(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_OPTIMUS_FLAGS,
+                                    0x3, &result);
 
         nouveau_optimus_dsm(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_OPTIMUS_CAPS,
                 NOUVEAU_DSM_OPTIMUS_SET_POWERDOWN, &result);