Example #1
0
void intel_gt_workarounds_apply(struct drm_i915_private *dev_priv)
{
	if (INTEL_GEN(dev_priv) < 8)
		return;
	else if (IS_BROADWELL(dev_priv))
		bdw_gt_workarounds_apply(dev_priv);
	else if (IS_CHERRYVIEW(dev_priv))
		chv_gt_workarounds_apply(dev_priv);
	else if (IS_SKYLAKE(dev_priv))
		skl_gt_workarounds_apply(dev_priv);
	else if (IS_BROXTON(dev_priv))
		bxt_gt_workarounds_apply(dev_priv);
	else if (IS_KABYLAKE(dev_priv))
		kbl_gt_workarounds_apply(dev_priv);
	else if (IS_GEMINILAKE(dev_priv))
		glk_gt_workarounds_apply(dev_priv);
	else if (IS_COFFEELAKE(dev_priv))
		cfl_gt_workarounds_apply(dev_priv);
	else if (IS_CANNONLAKE(dev_priv))
		cnl_gt_workarounds_apply(dev_priv);
	else if (IS_ICELAKE(dev_priv))
		icl_gt_workarounds_apply(dev_priv);
	else
		MISSING_CASE(INTEL_GEN(dev_priv));
}
Example #2
0
/**
 * intel_guc_fw_select() - selects GuC firmware for uploading
 *
 * @guc:	intel_guc struct
 *
 * Return: zero when we know firmware, non-zero in other case
 */
int intel_guc_fw_select(struct intel_guc *guc)
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);

	intel_uc_fw_init(&guc->fw, INTEL_UC_FW_TYPE_GUC);

	if (i915_modparams.guc_firmware_path) {
		guc->fw.path = i915_modparams.guc_firmware_path;
		guc->fw.major_ver_wanted = 0;
		guc->fw.minor_ver_wanted = 0;
	} else if (IS_SKYLAKE(dev_priv)) {
		guc->fw.path = I915_SKL_GUC_UCODE;
		guc->fw.major_ver_wanted = SKL_FW_MAJOR;
		guc->fw.minor_ver_wanted = SKL_FW_MINOR;
	} else if (IS_BROXTON(dev_priv)) {
		guc->fw.path = I915_BXT_GUC_UCODE;
		guc->fw.major_ver_wanted = BXT_FW_MAJOR;
		guc->fw.minor_ver_wanted = BXT_FW_MINOR;
	} else if (IS_KABYLAKE(dev_priv) || IS_COFFEELAKE(dev_priv)) {
		guc->fw.path = I915_KBL_GUC_UCODE;
		guc->fw.major_ver_wanted = KBL_FW_MAJOR;
		guc->fw.minor_ver_wanted = KBL_FW_MINOR;
	} else if (IS_GEMINILAKE(dev_priv)) {
		guc->fw.path = I915_GLK_GUC_UCODE;
		guc->fw.major_ver_wanted = GLK_FW_MAJOR;
		guc->fw.minor_ver_wanted = GLK_FW_MINOR;
	} else {
		DRM_ERROR("No GuC firmware known for platform with GuC!\n");
		return -ENOENT;
	}

	return 0;
}
Example #3
0
static void intel_fbc_get_reg_params(struct intel_crtc *crtc,
				     struct intel_fbc_reg_params *params)
{
	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
	struct intel_fbc *fbc = &dev_priv->fbc;
	struct intel_fbc_state_cache *cache = &fbc->state_cache;

	/* Since all our fields are integer types, use memset here so the
	 * comparison function can rely on memcmp because the padding will be
	 * zero. */
	memset(params, 0, sizeof(*params));

	params->vma = cache->vma;

	params->crtc.pipe = crtc->pipe;
	params->crtc.i9xx_plane = to_intel_plane(crtc->base.primary)->i9xx_plane;
	params->crtc.fence_y_offset = get_crtc_fence_y_offset(fbc);

	params->fb.format = cache->fb.format;
	params->fb.stride = cache->fb.stride;

	params->cfb_size = intel_fbc_calculate_cfb_size(dev_priv, cache);

	if (IS_GEN9(dev_priv) && !IS_GEMINILAKE(dev_priv))
		params->gen9_wa_cfb_stride = DIV_ROUND_UP(cache->plane.src_w,
						32 * fbc->threshold) * 8;
}
Example #4
0
static struct whitelist *whitelist_build(struct intel_engine_cs *engine,
					 struct whitelist *w)
{
	struct drm_i915_private *i915 = engine->i915;

	GEM_BUG_ON(engine->id != RCS);

	w->count = 0;
	w->nopid = i915_mmio_reg_offset(RING_NOPID(engine->mmio_base));

	if (INTEL_GEN(i915) < 8)
		return NULL;
	else if (IS_BROADWELL(i915))
		bdw_whitelist_build(w);
	else if (IS_CHERRYVIEW(i915))
		chv_whitelist_build(w);
	else if (IS_SKYLAKE(i915))
		skl_whitelist_build(w);
	else if (IS_BROXTON(i915))
		bxt_whitelist_build(w);
	else if (IS_KABYLAKE(i915))
		kbl_whitelist_build(w);
	else if (IS_GEMINILAKE(i915))
		glk_whitelist_build(w);
	else if (IS_COFFEELAKE(i915))
		cfl_whitelist_build(w);
	else if (IS_CANNONLAKE(i915))
		cnl_whitelist_build(w);
	else if (IS_ICELAKE(i915))
		icl_whitelist_build(w);
	else
		MISSING_CASE(INTEL_GEN(i915));

	return w;
}
Example #5
0
int intel_ctx_workarounds_init(struct drm_i915_private *dev_priv)
{
	int err = 0;

	dev_priv->workarounds.count = 0;

	if (INTEL_GEN(dev_priv) < 8)
		err = 0;
	else if (IS_BROADWELL(dev_priv))
		err = bdw_ctx_workarounds_init(dev_priv);
	else if (IS_CHERRYVIEW(dev_priv))
		err = chv_ctx_workarounds_init(dev_priv);
	else if (IS_SKYLAKE(dev_priv))
		err = skl_ctx_workarounds_init(dev_priv);
	else if (IS_BROXTON(dev_priv))
		err = bxt_ctx_workarounds_init(dev_priv);
	else if (IS_KABYLAKE(dev_priv))
		err = kbl_ctx_workarounds_init(dev_priv);
	else if (IS_GEMINILAKE(dev_priv))
		err = glk_ctx_workarounds_init(dev_priv);
	else if (IS_COFFEELAKE(dev_priv))
		err = cfl_ctx_workarounds_init(dev_priv);
	else if (IS_CANNONLAKE(dev_priv))
		err = cnl_ctx_workarounds_init(dev_priv);
	else if (IS_ICELAKE(dev_priv))
		err = icl_ctx_workarounds_init(dev_priv);
	else
		MISSING_CASE(INTEL_GEN(dev_priv));
	if (err)
		return err;

	DRM_DEBUG_DRIVER("Number of context specific w/a: %d\n",
			 dev_priv->workarounds.count);
	return 0;
}
Example #6
0
/**
 * intel_csr_ucode_init() - initialize the firmware loading.
 * @dev_priv: i915 drm device.
 *
 * This function is called at the time of loading the display driver to read
 * firmware from a .bin file and copied into a internal memory.
 */
void intel_csr_ucode_init(struct drm_i915_private *dev_priv)
{
	struct intel_csr *csr = &dev_priv->csr;

	INIT_WORK(&dev_priv->csr.work, csr_load_work_fn);

	if (!HAS_CSR(dev_priv))
		return;

	if (IS_GEMINILAKE(dev_priv))
		csr->fw_path = I915_CSR_GLK;
	else if (IS_KABYLAKE(dev_priv))
		csr->fw_path = I915_CSR_KBL;
	else if (IS_SKYLAKE(dev_priv))
		csr->fw_path = I915_CSR_SKL;
	else if (IS_BROXTON(dev_priv))
		csr->fw_path = I915_CSR_BXT;
	else {
		DRM_ERROR("Unexpected: no known CSR firmware for platform\n");
		return;
	}

	DRM_DEBUG_KMS("Loading %s\n", csr->fw_path);

	/*
	 * Obtain a runtime pm reference, until CSR is loaded,
	 * to avoid entering runtime-suspend.
	 */
	intel_display_power_get(dev_priv, POWER_DOMAIN_INIT);

	schedule_work(&dev_priv->csr.work);
}
Example #7
0
/**
 * intel_csr_ucode_init() - initialize the firmware loading.
 * @dev_priv: i915 drm device.
 *
 * This function is called at the time of loading the display driver to read
 * firmware from a .bin file and copied into a internal memory.
 */
void intel_csr_ucode_init(struct drm_i915_private *dev_priv)
{
	struct intel_csr *csr = &dev_priv->csr;

	INIT_WORK(&dev_priv->csr.work, csr_load_work_fn);

	if (!HAS_CSR(dev_priv))
		return;

	if (i915_modparams.dmc_firmware_path)
		csr->fw_path = i915_modparams.dmc_firmware_path;
	else if (IS_ICELAKE(dev_priv))
		csr->fw_path = I915_CSR_ICL;
	else if (IS_CANNONLAKE(dev_priv))
		csr->fw_path = I915_CSR_CNL;
	else if (IS_GEMINILAKE(dev_priv))
		csr->fw_path = I915_CSR_GLK;
	else if (IS_KABYLAKE(dev_priv) || IS_COFFEELAKE(dev_priv))
		csr->fw_path = I915_CSR_KBL;
	else if (IS_SKYLAKE(dev_priv))
		csr->fw_path = I915_CSR_SKL;
	else if (IS_BROXTON(dev_priv))
		csr->fw_path = I915_CSR_BXT;

	/*
	 * Obtain a runtime pm reference, until CSR is loaded,
	 * to avoid entering runtime-suspend.
	 */
	intel_display_power_get(dev_priv, POWER_DOMAIN_INIT);

	if (csr->fw_path == NULL) {
		DRM_DEBUG_KMS("No known CSR firmware for platform, disabling runtime PM\n");
		WARN_ON(!IS_ALPHA_SUPPORT(INTEL_INFO(dev_priv)));

		return;
	}

	DRM_DEBUG_KMS("Loading %s\n", csr->fw_path);
	schedule_work(&dev_priv->csr.work);
}
Example #8
0
static void guc_fw_select(struct intel_uc_fw *guc_fw)
{
	struct intel_guc *guc = container_of(guc_fw, struct intel_guc, fw);
	struct drm_i915_private *i915 = guc_to_i915(guc);

	GEM_BUG_ON(guc_fw->type != INTEL_UC_FW_TYPE_GUC);

	if (!HAS_GUC(i915))
		return;

	if (i915_modparams.guc_firmware_path) {
		guc_fw->path = i915_modparams.guc_firmware_path;
		guc_fw->major_ver_wanted = 0;
		guc_fw->minor_ver_wanted = 0;
	} else if (IS_ICELAKE(i915)) {
		guc_fw->path = ICL_GUC_FIRMWARE_PATH;
		guc_fw->major_ver_wanted = ICL_GUC_FW_MAJOR;
		guc_fw->minor_ver_wanted = ICL_GUC_FW_MINOR;
	} else if (IS_GEMINILAKE(i915)) {
		guc_fw->path = GLK_GUC_FIRMWARE_PATH;
		guc_fw->major_ver_wanted = GLK_GUC_FW_MAJOR;
		guc_fw->minor_ver_wanted = GLK_GUC_FW_MINOR;
	} else if (IS_KABYLAKE(i915) || IS_COFFEELAKE(i915)) {
		guc_fw->path = KBL_GUC_FIRMWARE_PATH;
		guc_fw->major_ver_wanted = KBL_GUC_FW_MAJOR;
		guc_fw->minor_ver_wanted = KBL_GUC_FW_MINOR;
	} else if (IS_BROXTON(i915)) {
		guc_fw->path = BXT_GUC_FIRMWARE_PATH;
		guc_fw->major_ver_wanted = BXT_GUC_FW_MAJOR;
		guc_fw->minor_ver_wanted = BXT_GUC_FW_MINOR;
	} else if (IS_SKYLAKE(i915)) {
		guc_fw->path = SKL_GUC_FIRMWARE_PATH;
		guc_fw->major_ver_wanted = SKL_GUC_FW_MAJOR;
		guc_fw->minor_ver_wanted = SKL_GUC_FW_MINOR;
	}
}
Example #9
0
bool bxt_dsi_pll_is_enabled(struct drm_i915_private *dev_priv)
{
	bool enabled;
	u32 val;
	u32 mask;

	mask = BXT_DSI_PLL_DO_ENABLE | BXT_DSI_PLL_LOCKED;
	val = I915_READ(BXT_DSI_PLL_ENABLE);
	enabled = (val & mask) == mask;

	if (!enabled)
		return false;

	/*
	 * Dividers must be programmed with valid values. As per BSEPC, for
	 * GEMINLAKE only PORT A divider values are checked while for BXT
	 * both divider values are validated. Check this here for
	 * paranoia, since BIOS is known to misconfigure PLLs in this way at
	 * times, and since accessing DSI registers with invalid dividers
	 * causes a system hang.
	 */
	val = I915_READ(BXT_DSI_PLL_CTL);
	if (IS_GEMINILAKE(dev_priv)) {
		if (!(val & BXT_DSIA_16X_MASK)) {
			DRM_DEBUG_DRIVER("Invalid PLL divider (%08x)\n", val);
			enabled = false;
		}
	} else {
		if (!(val & BXT_DSIA_16X_MASK) || !(val & BXT_DSIC_16X_MASK)) {
			DRM_DEBUG_DRIVER("Invalid PLL divider (%08x)\n", val);
			enabled = false;
		}
	}

	return enabled;
}
Example #10
0
static void gen7_fbc_activate(struct drm_i915_private *dev_priv)
{
	struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
	u32 dpfc_ctl;
	int threshold = dev_priv->fbc.threshold;

	/* Display WA #0529: skl, kbl, bxt. */
	if (IS_GEN9(dev_priv) && !IS_GEMINILAKE(dev_priv)) {
		u32 val = I915_READ(CHICKEN_MISC_4);

		val &= ~(FBC_STRIDE_OVERRIDE | FBC_STRIDE_MASK);

		if (i915_gem_object_get_tiling(params->vma->obj) !=
		    I915_TILING_X)
			val |= FBC_STRIDE_OVERRIDE | params->gen9_wa_cfb_stride;

		I915_WRITE(CHICKEN_MISC_4, val);
	}

	dpfc_ctl = 0;
	if (IS_IVYBRIDGE(dev_priv))
		dpfc_ctl |= IVB_DPFC_CTL_PLANE(params->crtc.i9xx_plane);

	if (params->fb.format->cpp[0] == 2)
		threshold++;

	switch (threshold) {
	case 4:
	case 3:
		dpfc_ctl |= DPFC_CTL_LIMIT_4X;
		break;
	case 2:
		dpfc_ctl |= DPFC_CTL_LIMIT_2X;
		break;
	case 1:
		dpfc_ctl |= DPFC_CTL_LIMIT_1X;
		break;
	}

	if (params->vma->fence) {
		dpfc_ctl |= IVB_DPFC_CTL_FENCE_EN;
		I915_WRITE(SNB_DPFC_CTL_SA,
			   SNB_CPU_FENCE_ENABLE |
			   params->vma->fence->id);
		I915_WRITE(DPFC_CPU_FENCE_OFFSET, params->crtc.fence_y_offset);
	} else {
		I915_WRITE(SNB_DPFC_CTL_SA,0);
		I915_WRITE(DPFC_CPU_FENCE_OFFSET, 0);
	}

	if (dev_priv->fbc.false_color)
		dpfc_ctl |= FBC_CTL_FALSE_COLOR;

	if (IS_IVYBRIDGE(dev_priv)) {
		/* WaFbcAsynchFlipDisableFbcQueue:ivb */
		I915_WRITE(ILK_DISPLAY_CHICKEN1,
			   I915_READ(ILK_DISPLAY_CHICKEN1) |
			   ILK_FBCQ_DIS);
	} else if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) {
		/* WaFbcAsynchFlipDisableFbcQueue:hsw,bdw */
		I915_WRITE(CHICKEN_PIPESL_1(params->crtc.pipe),
			   I915_READ(CHICKEN_PIPESL_1(params->crtc.pipe)) |
			   HSW_FBCQ_DIS);
	}

	I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);

	intel_fbc_recompress(dev_priv);
}
Example #11
0
/**
 * intel_csr_ucode_init() - initialize the firmware loading.
 * @dev_priv: i915 drm device.
 *
 * This function is called at the time of loading the display driver to read
 * firmware from a .bin file and copied into a internal memory.
 */
void intel_csr_ucode_init(struct drm_i915_private *dev_priv)
{
	struct intel_csr *csr = &dev_priv->csr;

	INIT_WORK(&dev_priv->csr.work, csr_load_work_fn);

	if (!HAS_CSR(dev_priv))
		return;

	/*
	 * Obtain a runtime pm reference, until CSR is loaded, to avoid entering
	 * runtime-suspend.
	 *
	 * On error, we return with the rpm wakeref held to prevent runtime
	 * suspend as runtime suspend *requires* a working CSR for whatever
	 * reason.
	 */
	intel_csr_runtime_pm_get(dev_priv);

	if (INTEL_GEN(dev_priv) >= 12) {
		/* Allow to load fw via parameter using the last known size */
		csr->max_fw_size = GEN12_CSR_MAX_FW_SIZE;
	} else if (IS_GEN(dev_priv, 11)) {
		csr->fw_path = ICL_CSR_PATH;
		csr->required_version = ICL_CSR_VERSION_REQUIRED;
		csr->max_fw_size = ICL_CSR_MAX_FW_SIZE;
	} else if (IS_CANNONLAKE(dev_priv)) {
		csr->fw_path = CNL_CSR_PATH;
		csr->required_version = CNL_CSR_VERSION_REQUIRED;
		csr->max_fw_size = CNL_CSR_MAX_FW_SIZE;
	} else if (IS_GEMINILAKE(dev_priv)) {
		csr->fw_path = GLK_CSR_PATH;
		csr->required_version = GLK_CSR_VERSION_REQUIRED;
		csr->max_fw_size = GLK_CSR_MAX_FW_SIZE;
	} else if (IS_KABYLAKE(dev_priv) || IS_COFFEELAKE(dev_priv)) {
		csr->fw_path = KBL_CSR_PATH;
		csr->required_version = KBL_CSR_VERSION_REQUIRED;
		csr->max_fw_size = KBL_CSR_MAX_FW_SIZE;
	} else if (IS_SKYLAKE(dev_priv)) {
		csr->fw_path = SKL_CSR_PATH;
		csr->required_version = SKL_CSR_VERSION_REQUIRED;
		csr->max_fw_size = SKL_CSR_MAX_FW_SIZE;
	} else if (IS_BROXTON(dev_priv)) {
		csr->fw_path = BXT_CSR_PATH;
		csr->required_version = BXT_CSR_VERSION_REQUIRED;
		csr->max_fw_size = BXT_CSR_MAX_FW_SIZE;
	}

	if (i915_modparams.dmc_firmware_path) {
		if (strlen(i915_modparams.dmc_firmware_path) == 0) {
			csr->fw_path = NULL;
			DRM_INFO("Disabling CSR firmware and runtime PM\n");
			return;
		}

		csr->fw_path = i915_modparams.dmc_firmware_path;
		/* Bypass version check for firmware override. */
		csr->required_version = 0;
	}

	if (csr->fw_path == NULL) {
		DRM_DEBUG_KMS("No known CSR firmware for platform, disabling runtime PM\n");
		WARN_ON(!IS_ALPHA_SUPPORT(INTEL_INFO(dev_priv)));

		return;
	}

	DRM_DEBUG_KMS("Loading %s\n", csr->fw_path);
	schedule_work(&dev_priv->csr.work);
}
Example #12
0
static uint32_t *parse_csr_fw(struct drm_i915_private *dev_priv,
			      const struct firmware *fw)
{
	struct intel_css_header *css_header;
	struct intel_package_header *package_header;
	struct intel_dmc_header *dmc_header;
	struct intel_csr *csr = &dev_priv->csr;
	const struct stepping_info *si = intel_get_stepping_info(dev_priv);
	uint32_t dmc_offset = CSR_DEFAULT_FW_OFFSET, readcount = 0, nbytes;
	uint32_t i;
	uint32_t *dmc_payload;
	uint32_t required_version;

	if (!fw)
		return NULL;

	/* Extract CSS Header information*/
	css_header = (struct intel_css_header *)fw->data;
	if (sizeof(struct intel_css_header) !=
	    (css_header->header_len * 4)) {
		DRM_ERROR("Firmware has wrong CSS header length %u bytes\n",
			  (css_header->header_len * 4));
		return NULL;
	}

	csr->version = css_header->version;

	if (IS_GEMINILAKE(dev_priv)) {
		required_version = GLK_CSR_VERSION_REQUIRED;
	} else if (IS_KABYLAKE(dev_priv)) {
		required_version = KBL_CSR_VERSION_REQUIRED;
	} else if (IS_SKYLAKE(dev_priv)) {
		required_version = SKL_CSR_VERSION_REQUIRED;
	} else if (IS_BROXTON(dev_priv)) {
		required_version = BXT_CSR_VERSION_REQUIRED;
	} else {
		MISSING_CASE(INTEL_REVID(dev_priv));
		required_version = 0;
	}

	if (csr->version != required_version) {
		DRM_INFO("Refusing to load DMC firmware v%u.%u,"
			 " please use v%u.%u [" FIRMWARE_URL "].\n",
			 CSR_VERSION_MAJOR(csr->version),
			 CSR_VERSION_MINOR(csr->version),
			 CSR_VERSION_MAJOR(required_version),
			 CSR_VERSION_MINOR(required_version));
		return NULL;
	}

	readcount += sizeof(struct intel_css_header);

	/* Extract Package Header information*/
	package_header = (struct intel_package_header *)
		&fw->data[readcount];
	if (sizeof(struct intel_package_header) !=
	    (package_header->header_len * 4)) {
		DRM_ERROR("Firmware has wrong package header length %u bytes\n",
			  (package_header->header_len * 4));
		return NULL;
	}
	readcount += sizeof(struct intel_package_header);

	/* Search for dmc_offset to find firware binary. */
	for (i = 0; i < package_header->num_entries; i++) {
		if (package_header->fw_info[i].substepping == '*' &&
		    si->stepping == package_header->fw_info[i].stepping) {
			dmc_offset = package_header->fw_info[i].offset;
			break;
		} else if (si->stepping == package_header->fw_info[i].stepping &&
			   si->substepping == package_header->fw_info[i].substepping) {
			dmc_offset = package_header->fw_info[i].offset;
			break;
		} else if (package_header->fw_info[i].stepping == '*' &&
			   package_header->fw_info[i].substepping == '*')
			dmc_offset = package_header->fw_info[i].offset;
	}
	if (dmc_offset == CSR_DEFAULT_FW_OFFSET) {
		DRM_ERROR("Firmware not supported for %c stepping\n",
			  si->stepping);
		return NULL;
	}
	readcount += dmc_offset;

	/* Extract dmc_header information. */
	dmc_header = (struct intel_dmc_header *)&fw->data[readcount];
	if (sizeof(struct intel_dmc_header) != (dmc_header->header_len)) {
		DRM_ERROR("Firmware has wrong dmc header length %u bytes\n",
			  (dmc_header->header_len));
		return NULL;
	}
	readcount += sizeof(struct intel_dmc_header);

	/* Cache the dmc header info. */
	if (dmc_header->mmio_count > ARRAY_SIZE(csr->mmioaddr)) {
		DRM_ERROR("Firmware has wrong mmio count %u\n",
			  dmc_header->mmio_count);
		return NULL;
	}
	csr->mmio_count = dmc_header->mmio_count;
	for (i = 0; i < dmc_header->mmio_count; i++) {
		if (dmc_header->mmioaddr[i] < CSR_MMIO_START_RANGE ||
		    dmc_header->mmioaddr[i] > CSR_MMIO_END_RANGE) {
			DRM_ERROR(" Firmware has wrong mmio address 0x%x\n",
				  dmc_header->mmioaddr[i]);
			return NULL;
		}
		csr->mmioaddr[i] = _MMIO(dmc_header->mmioaddr[i]);
		csr->mmiodata[i] = dmc_header->mmiodata[i];
	}

	/* fw_size is in dwords, so multiplied by 4 to convert into bytes. */
	nbytes = dmc_header->fw_size * 4;
	if (nbytes > CSR_MAX_FW_SIZE) {
		DRM_ERROR("CSR firmware too big (%u) bytes\n", nbytes);
		return NULL;
	}
	csr->dmc_fw_size = dmc_header->fw_size;

	dmc_payload = kmalloc(nbytes, GFP_KERNEL);
	if (!dmc_payload) {
		DRM_ERROR("Memory allocation failed for dmc payload\n");
		return NULL;
	}

	return memcpy(dmc_payload, &fw->data[readcount], nbytes);
}