drivers/gpu/drm/amd/amdgpu/amdgpu_bios.c - linux - Git at Google

 /*
  * Copyright 2008 Advanced Micro Devices, Inc.
  * Copyright 2008 Red Hat Inc.
  * Copyright 2009 Jerome Glisse.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  * and/or sell copies of the Software, and to permit persons to whom the
  * Software is furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  * OTHER DEALINGS IN THE SOFTWARE.
  *
  * Authors: Dave Airlie
  *          Alex Deucher
  *          Jerome Glisse
  */

 #include "amdgpu.h"
 #include "atom.h"

 #include <linux/pci.h>
 #include <linux/slab.h>
 #include <linux/acpi.h>
 /*
  * BIOS.
  */

 #define AMD_VBIOS_SIGNATURE " 761295520"
 #define AMD_VBIOS_SIGNATURE_OFFSET 0x30
 #define AMD_VBIOS_SIGNATURE_SIZE sizeof(AMD_VBIOS_SIGNATURE)
 #define AMD_VBIOS_SIGNATURE_END (AMD_VBIOS_SIGNATURE_OFFSET + AMD_VBIOS_SIGNATURE_SIZE)
 #define AMD_IS_VALID_VBIOS(p) ((p)[0] == 0x55 && (p)[1] == 0xAA)
 #define AMD_VBIOS_LENGTH(p) ((p)[2] << 9)

 /* Check if current bios is an ATOM BIOS.
  * Return true if it is ATOM BIOS. Otherwise, return false.
  */
 static bool check_atom_bios(uint8_t *bios, size_t size)
 {
 	uint16_t tmp, bios_header_start;

 	if (!bios || size < 0x49) {
 		DRM_INFO("vbios mem is null or mem size is wrong\n");
 		return false;
 	}

 	if (!AMD_IS_VALID_VBIOS(bios)) {
 		DRM_INFO("BIOS signature incorrect %x %x\n", bios[0], bios[1]);
 		return false;
 	}

 	bios_header_start = bios[0x48] | (bios[0x49] << 8);
 	if (!bios_header_start) {
 		DRM_INFO("Can't locate bios header\n");
 		return false;
 	}

 	tmp = bios_header_start + 4;
 	if (size < tmp) {
 		DRM_INFO("BIOS header is broken\n");
 		return false;
 	}

 	if (!memcmp(bios + tmp, "ATOM", 4) ||
 	    !memcmp(bios + tmp, "MOTA", 4)) {
 		DRM_DEBUG("ATOMBIOS detected\n");
 		return true;
 	}

 	return false;
 }

 /* If you boot an IGP board with a discrete card as the primary,
  * the IGP rom is not accessible via the rom bar as the IGP rom is
  * part of the system bios.  On boot, the system bios puts a
  * copy of the igp rom at the start of vram if a discrete card is
  * present.
  */
 static bool igp_read_bios_from_vram(struct amdgpu_device *adev)
 {
 	uint8_t __iomem *bios;
 	resource_size_t vram_base;
 	resource_size_t size = 256 * 1024; /* ??? */

 	if (!(adev->flags & AMD_IS_APU))
 		if (amdgpu_device_need_post(adev))
 			return false;

 	adev->bios = NULL;
 	vram_base = pci_resource_start(adev->pdev, 0);
 	bios = ioremap_wc(vram_base, size);
 	if (!bios) {
 		return false;
 	}

 	adev->bios = kmalloc(size, GFP_KERNEL);
 	if (!adev->bios) {
 		iounmap(bios);
 		return false;
 	}
 	adev->bios_size = size;
 	memcpy_fromio(adev->bios, bios, size);
 	iounmap(bios);

 	if (!check_atom_bios(adev->bios, size)) {
 		kfree(adev->bios);
 		return false;
 	}

 	return true;
 }

 bool amdgpu_read_bios(struct amdgpu_device *adev)
 {
 	uint8_t __iomem *bios;
 	size_t size;

 	adev->bios = NULL;
 	/* XXX: some cards may return 0 for rom size? ddx has a workaround */
 	bios = pci_map_rom(adev->pdev, &size);
 	if (!bios) {
 		return false;
 	}

 	adev->bios = kzalloc(size, GFP_KERNEL);
 	if (adev->bios == NULL) {
 		pci_unmap_rom(adev->pdev, bios);
 		return false;
 	}
 	adev->bios_size = size;
 	memcpy_fromio(adev->bios, bios, size);
 	pci_unmap_rom(adev->pdev, bios);

 	if (!check_atom_bios(adev->bios, size)) {
 		kfree(adev->bios);
 		return false;
 	}

 	return true;
 }

 static bool amdgpu_read_bios_from_rom(struct amdgpu_device *adev)
 {
 	u8 header[AMD_VBIOS_SIGNATURE_END+1] = {0};
 	int len;

 	if (!adev->asic_funcs->read_bios_from_rom)
 		return false;

 	/* validate VBIOS signature */
 	if (amdgpu_asic_read_bios_from_rom(adev, &header[0], sizeof(header)) == false)
 		return false;
 	header[AMD_VBIOS_SIGNATURE_END] = 0;

 	if ((!AMD_IS_VALID_VBIOS(header)) ||
 	    0 != memcmp((char *)&header[AMD_VBIOS_SIGNATURE_OFFSET],
 			AMD_VBIOS_SIGNATURE,
 			strlen(AMD_VBIOS_SIGNATURE)))
 		return false;

 	/* valid vbios, go on */
 	len = AMD_VBIOS_LENGTH(header);
 	len = ALIGN(len, 4);
 	adev->bios = kmalloc(len, GFP_KERNEL);
 	if (!adev->bios) {
 		DRM_ERROR("no memory to allocate for BIOS\n");
 		return false;
 	}
 	adev->bios_size = len;

 	/* read complete BIOS */
 	amdgpu_asic_read_bios_from_rom(adev, adev->bios, len);

 	if (!check_atom_bios(adev->bios, len)) {
 		kfree(adev->bios);
 		return false;
 	}

 	return true;
 }

 static bool amdgpu_read_platform_bios(struct amdgpu_device *adev)
 {
 	phys_addr_t rom = adev->pdev->rom;
 	size_t romlen = adev->pdev->romlen;
 	void __iomem *bios;

 	adev->bios = NULL;

 	if (!rom || romlen == 0)
 		return false;

 	adev->bios = kzalloc(romlen, GFP_KERNEL);
 	if (!adev->bios)
 		return false;

 	bios = ioremap(rom, romlen);
 	if (!bios)
 		goto free_bios;

 	memcpy_fromio(adev->bios, bios, romlen);
 	iounmap(bios);

 	if (!check_atom_bios(adev->bios, romlen))
 		goto free_bios;

 	adev->bios_size = romlen;

 	return true;
 free_bios:
 	kfree(adev->bios);
 	return false;
 }

 #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
 /**
  * amdgpu_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 amdgpu_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 amdgpu_atrm_get_bios(struct amdgpu_device *adev)
 {
 	int ret;
 	int size = 256 * 1024;
 	int i;
 	struct pci_dev *pdev = NULL;
 	acpi_handle dhandle, atrm_handle;
 	acpi_status status;
 	bool found = false;

 	/* ATRM is for the discrete card only */
 	if (adev->flags & AMD_IS_APU)
 		return false;

 	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
 		dhandle = ACPI_HANDLE(&pdev->dev);
 		if (!dhandle)
 			continue;

 		status = acpi_get_handle(dhandle, "ATRM", &atrm_handle);
 		if (!ACPI_FAILURE(status)) {
 			found = true;
 			break;
 		}
 	}

 	if (!found) {
 		while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
 			dhandle = 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;

 	adev->bios = kmalloc(size, GFP_KERNEL);
 	if (!adev->bios) {
 		DRM_ERROR("Unable to allocate bios\n");
 		return false;
 	}

 	for (i = 0; i < size / ATRM_BIOS_PAGE; i++) {
 		ret = amdgpu_atrm_call(atrm_handle,
 				       adev->bios,
 				       (i * ATRM_BIOS_PAGE),
 				       ATRM_BIOS_PAGE);
 		if (ret < ATRM_BIOS_PAGE)
 			break;
 	}

 	if (!check_atom_bios(adev->bios, size)) {
 		kfree(adev->bios);
 		return false;
 	}
 	adev->bios_size = size;
 	return true;
 }
 #else
 static inline bool amdgpu_atrm_get_bios(struct amdgpu_device *adev)
 {
 	return false;
 }
 #endif

 static bool amdgpu_read_disabled_bios(struct amdgpu_device *adev)
 {
 	if (adev->flags & AMD_IS_APU)
 		return igp_read_bios_from_vram(adev);
 	else
 		return amdgpu_asic_read_disabled_bios(adev);
 }

 #ifdef CONFIG_ACPI
 static bool amdgpu_acpi_vfct_bios(struct amdgpu_device *adev)
 {
 	struct acpi_table_header *hdr;
 	acpi_size tbl_size;
 	UEFI_ACPI_VFCT *vfct;
 	unsigned offset;

 	if (!ACPI_SUCCESS(acpi_get_table("VFCT", 1, &hdr)))
 		return false;
 	tbl_size = hdr->length;
 	if (tbl_size < sizeof(UEFI_ACPI_VFCT)) {
 		DRM_ERROR("ACPI VFCT table present but broken (too short #1)\n");
 		return false;
 	}

 	vfct = (UEFI_ACPI_VFCT *)hdr;
 	offset = vfct->VBIOSImageOffset;

 	while (offset < tbl_size) {
 		GOP_VBIOS_CONTENT *vbios = (GOP_VBIOS_CONTENT *)((char *)hdr + offset);
 		VFCT_IMAGE_HEADER *vhdr = &vbios->VbiosHeader;

 		offset += sizeof(VFCT_IMAGE_HEADER);
 		if (offset > tbl_size) {
 			DRM_ERROR("ACPI VFCT image header truncated\n");
 			return false;
 		}

 		offset += vhdr->ImageLength;
 		if (offset > tbl_size) {
 			DRM_ERROR("ACPI VFCT image truncated\n");
 			return false;
 		}

 		if (vhdr->ImageLength &&
 		    vhdr->PCIBus == adev->pdev->bus->number &&
 		    vhdr->PCIDevice == PCI_SLOT(adev->pdev->devfn) &&
 		    vhdr->PCIFunction == PCI_FUNC(adev->pdev->devfn) &&
 		    vhdr->VendorID == adev->pdev->vendor &&
 		    vhdr->DeviceID == adev->pdev->device) {
 			adev->bios = kmemdup(&vbios->VbiosContent,
 					     vhdr->ImageLength,
 					     GFP_KERNEL);

 			if (!check_atom_bios(adev->bios, vhdr->ImageLength)) {
 				kfree(adev->bios);
 				return false;
 			}
 			adev->bios_size = vhdr->ImageLength;
 			return true;
 		}
 	}

 	DRM_ERROR("ACPI VFCT table present but broken (too short #2)\n");
 	return false;
 }
 #else
 static inline bool amdgpu_acpi_vfct_bios(struct amdgpu_device *adev)
 {
 	return false;
 }
 #endif

 bool amdgpu_get_bios(struct amdgpu_device *adev)
 {
 	if (amdgpu_atrm_get_bios(adev)) {
 		dev_info(adev->dev, "Fetched VBIOS from ATRM\n");
 		goto success;
 	}

 	if (amdgpu_acpi_vfct_bios(adev)) {
 		dev_info(adev->dev, "Fetched VBIOS from VFCT\n");
 		goto success;
 	}

 	if (igp_read_bios_from_vram(adev)) {
 		dev_info(adev->dev, "Fetched VBIOS from VRAM BAR\n");
 		goto success;
 	}

 	if (amdgpu_read_bios(adev)) {
 		dev_info(adev->dev, "Fetched VBIOS from ROM BAR\n");
 		goto success;
 	}

 	if (amdgpu_read_bios_from_rom(adev)) {
 		dev_info(adev->dev, "Fetched VBIOS from ROM\n");
 		goto success;
 	}

 	if (amdgpu_read_disabled_bios(adev)) {
 		dev_info(adev->dev, "Fetched VBIOS from disabled ROM BAR\n");
 		goto success;
 	}

 	if (amdgpu_read_platform_bios(adev)) {
 		dev_info(adev->dev, "Fetched VBIOS from platform\n");
 		goto success;
 	}

 	DRM_ERROR("Unable to locate a BIOS ROM\n");
 	return false;

 success:
 	adev->is_atom_fw = (adev->asic_type >= CHIP_VEGA10) ? true : false;
 	return true;
 }
	/*
	* Copyright 2008 Advanced Micro Devices, Inc.
	* Copyright 2008 Red Hat Inc.
	* Copyright 2009 Jerome Glisse.
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the "Software"),
	* to deal in the Software without restriction, including without limitation
	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	* and/or sell copies of the Software, and to permit persons to whom the
	* Software is furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
	* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
	* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
	* OTHER DEALINGS IN THE SOFTWARE.
	*
	* Authors: Dave Airlie
	* Alex Deucher
	* Jerome Glisse
	*/

	#include "amdgpu.h"
	#include "atom.h"

	#include <linux/pci.h>
	#include <linux/slab.h>
	#include <linux/acpi.h>
	/*
	* BIOS.
	*/

	#define AMD_VBIOS_SIGNATURE " 761295520"
	#define AMD_VBIOS_SIGNATURE_OFFSET 0x30
	#define AMD_VBIOS_SIGNATURE_SIZE sizeof(AMD_VBIOS_SIGNATURE)
	#define AMD_VBIOS_SIGNATURE_END (AMD_VBIOS_SIGNATURE_OFFSET + AMD_VBIOS_SIGNATURE_SIZE)
	#define AMD_IS_VALID_VBIOS(p) ((p)[0] == 0x55 && (p)[1] == 0xAA)
	#define AMD_VBIOS_LENGTH(p) ((p)[2] << 9)

	/* Check if current bios is an ATOM BIOS.
	* Return true if it is ATOM BIOS. Otherwise, return false.
	*/
	static bool check_atom_bios(uint8_t *bios, size_t size)
	{
	uint16_t tmp, bios_header_start;

	if (!bios \|\| size < 0x49) {
	DRM_INFO("vbios mem is null or mem size is wrong\n");
	return false;
	}

	if (!AMD_IS_VALID_VBIOS(bios)) {
	DRM_INFO("BIOS signature incorrect %x %x\n", bios[0], bios[1]);
	return false;
	}

	bios_header_start = bios[0x48] \| (bios[0x49] << 8);
	if (!bios_header_start) {
	DRM_INFO("Can't locate bios header\n");
	return false;
	}

	tmp = bios_header_start + 4;
	if (size < tmp) {
	DRM_INFO("BIOS header is broken\n");
	return false;
	}

	if (!memcmp(bios + tmp, "ATOM", 4) \|\|
	!memcmp(bios + tmp, "MOTA", 4)) {
	DRM_DEBUG("ATOMBIOS detected\n");
	return true;
	}

	return false;
	}

	/* If you boot an IGP board with a discrete card as the primary,
	* the IGP rom is not accessible via the rom bar as the IGP rom is
	* part of the system bios. On boot, the system bios puts a
	* copy of the igp rom at the start of vram if a discrete card is
	* present.
	*/
	static bool igp_read_bios_from_vram(struct amdgpu_device *adev)
	{
	uint8_t __iomem *bios;
	resource_size_t vram_base;
	resource_size_t size = 256 * 1024; /* ??? */

	if (!(adev->flags & AMD_IS_APU))
	if (amdgpu_device_need_post(adev))
	return false;

	adev->bios = NULL;
	vram_base = pci_resource_start(adev->pdev, 0);
	bios = ioremap_wc(vram_base, size);
	if (!bios) {
	return false;
	}

	adev->bios = kmalloc(size, GFP_KERNEL);
	if (!adev->bios) {
	iounmap(bios);
	return false;
	}
	adev->bios_size = size;
	memcpy_fromio(adev->bios, bios, size);
	iounmap(bios);

	if (!check_atom_bios(adev->bios, size)) {
	kfree(adev->bios);
	return false;
	}

	return true;
	}

	bool amdgpu_read_bios(struct amdgpu_device *adev)
	{
	uint8_t __iomem *bios;
	size_t size;

	adev->bios = NULL;
	/* XXX: some cards may return 0 for rom size? ddx has a workaround */
	bios = pci_map_rom(adev->pdev, &size);
	if (!bios) {
	return false;
	}

	adev->bios = kzalloc(size, GFP_KERNEL);
	if (adev->bios == NULL) {
	pci_unmap_rom(adev->pdev, bios);
	return false;
	}
	adev->bios_size = size;
	memcpy_fromio(adev->bios, bios, size);
	pci_unmap_rom(adev->pdev, bios);

	if (!check_atom_bios(adev->bios, size)) {
	kfree(adev->bios);
	return false;
	}

	return true;
	}

	static bool amdgpu_read_bios_from_rom(struct amdgpu_device *adev)
	{
	u8 header[AMD_VBIOS_SIGNATURE_END+1] = {0};
	int len;

	if (!adev->asic_funcs->read_bios_from_rom)
	return false;

	/* validate VBIOS signature */
	if (amdgpu_asic_read_bios_from_rom(adev, &header[0], sizeof(header)) == false)
	return false;
	header[AMD_VBIOS_SIGNATURE_END] = 0;

	if ((!AMD_IS_VALID_VBIOS(header)) \|\|
	0 != memcmp((char *)&header[AMD_VBIOS_SIGNATURE_OFFSET],
	AMD_VBIOS_SIGNATURE,
	strlen(AMD_VBIOS_SIGNATURE)))
	return false;

	/* valid vbios, go on */
	len = AMD_VBIOS_LENGTH(header);
	len = ALIGN(len, 4);
	adev->bios = kmalloc(len, GFP_KERNEL);
	if (!adev->bios) {
	DRM_ERROR("no memory to allocate for BIOS\n");
	return false;
	}
	adev->bios_size = len;

	/* read complete BIOS */
	amdgpu_asic_read_bios_from_rom(adev, adev->bios, len);

	if (!check_atom_bios(adev->bios, len)) {
	kfree(adev->bios);
	return false;
	}

	return true;
	}

	static bool amdgpu_read_platform_bios(struct amdgpu_device *adev)
	{
	phys_addr_t rom = adev->pdev->rom;
	size_t romlen = adev->pdev->romlen;
	void __iomem *bios;

	adev->bios = NULL;

	if (!rom \|\| romlen == 0)
	return false;

	adev->bios = kzalloc(romlen, GFP_KERNEL);
	if (!adev->bios)
	return false;

	bios = ioremap(rom, romlen);
	if (!bios)
	goto free_bios;

	memcpy_fromio(adev->bios, bios, romlen);
	iounmap(bios);

	if (!check_atom_bios(adev->bios, romlen))
	goto free_bios;

	adev->bios_size = romlen;

	return true;
	free_bios:
	kfree(adev->bios);
	return false;
	}

	#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
	/**
	* amdgpu_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 amdgpu_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 amdgpu_atrm_get_bios(struct amdgpu_device *adev)
	{
	int ret;
	int size = 256 * 1024;
	int i;
	struct pci_dev *pdev = NULL;
	acpi_handle dhandle, atrm_handle;
	acpi_status status;
	bool found = false;

	/* ATRM is for the discrete card only */
	if (adev->flags & AMD_IS_APU)
	return false;

	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
	dhandle = ACPI_HANDLE(&pdev->dev);
	if (!dhandle)
	continue;

	status = acpi_get_handle(dhandle, "ATRM", &atrm_handle);
	if (!ACPI_FAILURE(status)) {
	found = true;
	break;
	}
	}

	if (!found) {
	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
	dhandle = 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;

	adev->bios = kmalloc(size, GFP_KERNEL);
	if (!adev->bios) {
	DRM_ERROR("Unable to allocate bios\n");
	return false;
	}

	for (i = 0; i < size / ATRM_BIOS_PAGE; i++) {
	ret = amdgpu_atrm_call(atrm_handle,
	adev->bios,
	(i * ATRM_BIOS_PAGE),
	ATRM_BIOS_PAGE);
	if (ret < ATRM_BIOS_PAGE)
	break;
	}

	if (!check_atom_bios(adev->bios, size)) {
	kfree(adev->bios);
	return false;
	}
	adev->bios_size = size;
	return true;
	}
	#else
	static inline bool amdgpu_atrm_get_bios(struct amdgpu_device *adev)
	{
	return false;
	}
	#endif

	static bool amdgpu_read_disabled_bios(struct amdgpu_device *adev)
	{
	if (adev->flags & AMD_IS_APU)
	return igp_read_bios_from_vram(adev);
	else
	return amdgpu_asic_read_disabled_bios(adev);
	}

	#ifdef CONFIG_ACPI
	static bool amdgpu_acpi_vfct_bios(struct amdgpu_device *adev)
	{
	struct acpi_table_header *hdr;
	acpi_size tbl_size;
	UEFI_ACPI_VFCT *vfct;
	unsigned offset;

	if (!ACPI_SUCCESS(acpi_get_table("VFCT", 1, &hdr)))
	return false;
	tbl_size = hdr->length;
	if (tbl_size < sizeof(UEFI_ACPI_VFCT)) {
	DRM_ERROR("ACPI VFCT table present but broken (too short #1)\n");
	return false;
	}

	vfct = (UEFI_ACPI_VFCT *)hdr;
	offset = vfct->VBIOSImageOffset;

	while (offset < tbl_size) {
	GOP_VBIOS_CONTENT vbios = (GOP_VBIOS_CONTENT )((char *)hdr + offset);
	VFCT_IMAGE_HEADER *vhdr = &vbios->VbiosHeader;

	offset += sizeof(VFCT_IMAGE_HEADER);
	if (offset > tbl_size) {
	DRM_ERROR("ACPI VFCT image header truncated\n");
	return false;
	}

	offset += vhdr->ImageLength;
	if (offset > tbl_size) {
	DRM_ERROR("ACPI VFCT image truncated\n");
	return false;
	}

	if (vhdr->ImageLength &&
	vhdr->PCIBus == adev->pdev->bus->number &&
	vhdr->PCIDevice == PCI_SLOT(adev->pdev->devfn) &&
	vhdr->PCIFunction == PCI_FUNC(adev->pdev->devfn) &&
	vhdr->VendorID == adev->pdev->vendor &&
	vhdr->DeviceID == adev->pdev->device) {
	adev->bios = kmemdup(&vbios->VbiosContent,
	vhdr->ImageLength,
	GFP_KERNEL);

	if (!check_atom_bios(adev->bios, vhdr->ImageLength)) {
	kfree(adev->bios);
	return false;
	}
	adev->bios_size = vhdr->ImageLength;
	return true;
	}
	}

	DRM_ERROR("ACPI VFCT table present but broken (too short #2)\n");
	return false;
	}
	#else
	static inline bool amdgpu_acpi_vfct_bios(struct amdgpu_device *adev)
	{
	return false;
	}
	#endif

	bool amdgpu_get_bios(struct amdgpu_device *adev)
	{
	if (amdgpu_atrm_get_bios(adev)) {
	dev_info(adev->dev, "Fetched VBIOS from ATRM\n");
	goto success;
	}

	if (amdgpu_acpi_vfct_bios(adev)) {
	dev_info(adev->dev, "Fetched VBIOS from VFCT\n");
	goto success;
	}

	if (igp_read_bios_from_vram(adev)) {
	dev_info(adev->dev, "Fetched VBIOS from VRAM BAR\n");
	goto success;
	}

	if (amdgpu_read_bios(adev)) {
	dev_info(adev->dev, "Fetched VBIOS from ROM BAR\n");
	goto success;
	}

	if (amdgpu_read_bios_from_rom(adev)) {
	dev_info(adev->dev, "Fetched VBIOS from ROM\n");
	goto success;
	}

	if (amdgpu_read_disabled_bios(adev)) {
	dev_info(adev->dev, "Fetched VBIOS from disabled ROM BAR\n");
	goto success;
	}

	if (amdgpu_read_platform_bios(adev)) {
	dev_info(adev->dev, "Fetched VBIOS from platform\n");
	goto success;
	}

	DRM_ERROR("Unable to locate a BIOS ROM\n");
	return false;

	success:
	adev->is_atom_fw = (adev->asic_type >= CHIP_VEGA10) ? true : false;
	return true;
	}