drm/radeon: split ATRM support out from the ATPX handler (v3)

There are systems that use ATRM, but not ATPX.

Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=41265

V2: fix #ifdefs as per Greg's comments
V3: fix it harder

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

drivers/gpu/drm/radeon/radeon.h

@@ -142,21 +142,6 @@ struct radeon_device;
 /*
  * BIOS.
  */
-#define ATRM_BIOS_PAGE 4096
-
-#if defined(CONFIG_VGA_SWITCHEROO)
-bool radeon_atrm_supported(struct pci_dev *pdev);
-int radeon_atrm_get_bios_chunk(uint8_t *bios, int offset, int len);
-#else
-static inline bool radeon_atrm_supported(struct pci_dev *pdev)
-{
-	return false;
-}
-
-static inline int radeon_atrm_get_bios_chunk(uint8_t *bios, int offset, int len){
-	return -EINVAL;
-}
-#endif
 bool radeon_get_bios(struct radeon_device *rdev);
 
 /*

drivers/gpu/drm/radeon/radeon_atpx_handler.c

@@ -30,57 +30,8 @@ static struct radeon_atpx_priv {
 	/* handle for device - and atpx */
 	acpi_handle dhandle;
 	acpi_handle atpx_handle;
-	acpi_handle atrm_handle;
 } radeon_atpx_priv;
 
-/* retrieve the ROM in 4k blocks */
-static int radeon_atrm_call(acpi_handle atrm_handle, uint8_t *bios,
-			    int offset, int len)
-{
-	acpi_status status;
-	union acpi_object atrm_arg_elements[2], *obj;
-	struct acpi_object_list atrm_arg;
-	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL};
-
-	atrm_arg.count = 2;
-	atrm_arg.pointer = &atrm_arg_elements[0];
-
-	atrm_arg_elements[0].type = ACPI_TYPE_INTEGER;
-	atrm_arg_elements[0].integer.value = offset;
-
-	atrm_arg_elements[1].type = ACPI_TYPE_INTEGER;
-	atrm_arg_elements[1].integer.value = len;
-
-	status = acpi_evaluate_object(atrm_handle, NULL, &atrm_arg, &buffer);
-	if (ACPI_FAILURE(status)) {
-		printk("failed to evaluate ATRM got %s\n", acpi_format_exception(status));
-		return -ENODEV;
-	}
-
-	obj = (union acpi_object *)buffer.pointer;
-	memcpy(bios+offset, obj->buffer.pointer, obj->buffer.length);
-	len = obj->buffer.length;
-	kfree(buffer.pointer);
-	return len;
-}
-
-bool radeon_atrm_supported(struct pci_dev *pdev)
-{
-	/* get the discrete ROM only via ATRM */
-	if (!radeon_atpx_priv.atpx_detected)
-		return false;
-
-	if (radeon_atpx_priv.dhandle == DEVICE_ACPI_HANDLE(&pdev->dev))
-		return false;
-	return true;
-}
-
-
-int radeon_atrm_get_bios_chunk(uint8_t *bios, int offset, int len)
-{
-	return radeon_atrm_call(radeon_atpx_priv.atrm_handle, bios, offset, len);
-}
-
 static int radeon_atpx_get_version(acpi_handle handle)
 {
 	acpi_status status;
@@ -198,7 +149,7 @@ static int radeon_atpx_power_state(enum vga_switcheroo_client_id id,
 
 static bool radeon_atpx_pci_probe_handle(struct pci_dev *pdev)
 {
-	acpi_handle dhandle, atpx_handle, atrm_handle;
+	acpi_handle dhandle, atpx_handle;
 	acpi_status status;
 
 	dhandle = DEVICE_ACPI_HANDLE(&pdev->dev);
@@ -209,13 +160,8 @@ static bool radeon_atpx_pci_probe_handle(struct pci_dev *pdev)
 	if (ACPI_FAILURE(status))
 		return false;
 
-	status = acpi_get_handle(dhandle, "ATRM", &atrm_handle);
-	if (ACPI_FAILURE(status))
-		return false;
-
 	radeon_atpx_priv.dhandle = dhandle;
 	radeon_atpx_priv.atpx_handle = atpx_handle;
-	radeon_atpx_priv.atrm_handle = atrm_handle;
 	return true;
 }
 

drivers/gpu/drm/radeon/radeon_bios.c

@@ -99,16 +99,81 @@ static bool radeon_read_bios(struct radeon_device *rdev)
 	return true;
 }
 
+#ifdef CONFIG_ACPI
 /* ATRM is used to get the BIOS on the discrete cards in
  * dual-gpu systems.
  */
+/* retrieve the ROM in 4k blocks */
+#define ATRM_BIOS_PAGE 4096
+/**
+ * radeon_atrm_call - fetch a chunk of the vbios
+ *
+ * @atrm_handle: acpi ATRM handle
+ * @bios: vbios image pointer
+ * @offset: offset of vbios image data to fetch
+ * @len: length of vbios image data to fetch
+ *
+ * Executes ATRM to fetch a chunk of the discrete
+ * vbios image on PX systems (all asics).
+ * Returns the length of the buffer fetched.
+ */
+static int radeon_atrm_call(acpi_handle atrm_handle, uint8_t *bios,
+			    int offset, int len)
+{
+	acpi_status status;
+	union acpi_object atrm_arg_elements[2], *obj;
+	struct acpi_object_list atrm_arg;
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL};
+
+	atrm_arg.count = 2;
+	atrm_arg.pointer = &atrm_arg_elements[0];
+
+	atrm_arg_elements[0].type = ACPI_TYPE_INTEGER;
+	atrm_arg_elements[0].integer.value = offset;
+
+	atrm_arg_elements[1].type = ACPI_TYPE_INTEGER;
+	atrm_arg_elements[1].integer.value = len;
+
+	status = acpi_evaluate_object(atrm_handle, NULL, &atrm_arg, &buffer);
+	if (ACPI_FAILURE(status)) {
+		printk("failed to evaluate ATRM got %s\n", acpi_format_exception(status));
+		return -ENODEV;
+	}
+
+	obj = (union acpi_object *)buffer.pointer;
+	memcpy(bios+offset, obj->buffer.pointer, obj->buffer.length);
+	len = obj->buffer.length;
+	kfree(buffer.pointer);
+	return len;
+}
+
 static bool radeon_atrm_get_bios(struct radeon_device *rdev)
 {
 	int ret;
 	int size = 256 * 1024;
 	int i;
+	struct pci_dev *pdev = NULL;
+	acpi_handle dhandle, atrm_handle;
+	acpi_status status;
+	bool found = false;
 
-	if (!radeon_atrm_supported(rdev->pdev))
+	/* ATRM is for the discrete card only */
+	if (rdev->flags & RADEON_IS_IGP)
+		return false;
+
+	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
+		dhandle = DEVICE_ACPI_HANDLE(&pdev->dev);
+		if (!dhandle)
+			continue;
+
+		status = acpi_get_handle(dhandle, "ATRM", &atrm_handle);
+		if (!ACPI_FAILURE(status)) {
+			found = true;
+			break;
+		}
+	}
+
+	if (!found)
 		return false;
 
 	rdev->bios = kmalloc(size, GFP_KERNEL);
@@ -118,9 +183,10 @@ static bool radeon_atrm_get_bios(struct radeon_device *rdev)
 	}
 
 	for (i = 0; i < size / ATRM_BIOS_PAGE; i++) {
-		ret = radeon_atrm_get_bios_chunk(rdev->bios,
-						 (i * ATRM_BIOS_PAGE),
-						 ATRM_BIOS_PAGE);
+		ret = radeon_atrm_call(atrm_handle,
+				       rdev->bios,
+				       (i * ATRM_BIOS_PAGE),
+				       ATRM_BIOS_PAGE);
 		if (ret < ATRM_BIOS_PAGE)
 			break;
 	}
@@ -131,6 +197,12 @@ static bool radeon_atrm_get_bios(struct radeon_device *rdev)
 	}
 	return true;
 }
+#else
+static inline bool radeon_atrm_get_bios(struct radeon_device *rdev)
+{
+	return false;
+}
+#endif
 
 static bool ni_read_disabled_bios(struct radeon_device *rdev)
 {