Commit 9066f83c authored by Chris Wilson's avatar Chris Wilson Committed by Dave Airlie
Browse files

drm: Try loading builtin EDIDs first 



If the firmware is not builtin and userspace is not yet running, we can
stall the boot process for a minute whilst the firmware loader times
out. This is contrary to expectations of providing a builtin EDID!

In the process, we can rearrange the code to make the error handling
more resilient and prevent gcc warning about unitialised variables along
the error paths.

v2: Load builtins first, fix gcc second (Jani) and cosmetics (Ville).
v3: Verify that we do not read beyond the end of the fwdata (Ville)

Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Reviewed-by: default avatarJani Nikula <jani.nikula@intel.com>
Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
parent c3a49737

drivers/gpu/drm/drm_edid_load.c

+54 −54
Original line number Diff line number Diff line
@@ -32,7 +32,7 @@ MODULE_PARM_DESC(edid_firmware, "Do not probe monitor, use specified EDID blob " 
	"from built-in data or /lib/firmware instead. ");



#define GENERIC_EDIDS 5

static char *generic_edid_name[GENERIC_EDIDS] = {

static const char *generic_edid_name[GENERIC_EDIDS] = {

	"edid/1024x768.bin",

	"edid/1280x1024.bin",

	"edid/1600x1200.bin",
@@ -40,7 +40,7 @@ static char *generic_edid_name[GENERIC_EDIDS] = { 
	"edid/1920x1080.bin",

};



static u8 generic_edid[GENERIC_EDIDS][128] = {

static const u8 generic_edid[GENERIC_EDIDS][128] = {

	{

	0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00,

	0x31, 0xd8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
@@ -133,63 +133,68 @@ static u8 generic_edid[GENERIC_EDIDS][128] = { 
	},

};



static int edid_size(const u8 *edid, int data_size)

{

	if (data_size < EDID_LENGTH)

		return 0;



	return (edid[0x7e] + 1) * EDID_LENGTH;

}



static u8 *edid_load(struct drm_connector *connector, const char *name,

			const char *connector_name)

{

	const struct firmware *fw;

	struct platform_device *pdev;

	u8 *fwdata = NULL, *edid, *new_edid;

	int fwsize, expected;

	int builtin = 0, err = 0;

	const struct firmware *fw = NULL;

	const u8 *fwdata;

	u8 *edid;

	int fwsize, builtin;

	int i, valid_extensions = 0;

	bool print_bad_edid = !connector->bad_edid_counter || (drm_debug & DRM_UT_KMS);



	builtin = 0;

	for (i = 0; i < GENERIC_EDIDS; i++) {

		if (strcmp(name, generic_edid_name[i]) == 0) {

			fwdata = generic_edid[i];

			fwsize = sizeof(generic_edid[i]);

			builtin = 1;

			break;

		}

	}

	if (!builtin) {

		struct platform_device *pdev;

		int err;



		pdev = platform_device_register_simple(connector_name, -1, NULL, 0);

		if (IS_ERR(pdev)) {

			DRM_ERROR("Failed to register EDID firmware platform device "

				  "for connector \"%s\"\n", connector_name);

		err = -EINVAL;

		goto out;

			return ERR_CAST(pdev);

		}



		err = request_firmware(&fw, name, &pdev->dev);

		platform_device_unregister(pdev);



	if (err) {

		i = 0;

		while (i < GENERIC_EDIDS && strcmp(name, generic_edid_name[i]))

			i++;

		if (i < GENERIC_EDIDS) {

			err = 0;

			builtin = 1;

			fwdata = generic_edid[i];

			fwsize = sizeof(generic_edid[i]);

		}

	}



		if (err) {

			DRM_ERROR("Requesting EDID firmware \"%s\" failed (err=%d)\n",

				  name, err);

		goto out;

			return ERR_PTR(err);

		}



	if (fwdata == NULL) {

		fwdata = (u8 *) fw->data;

		fwdata = fw->data;

		fwsize = fw->size;

	}



	expected = (fwdata[0x7e] + 1) * EDID_LENGTH;

	if (expected != fwsize) {

	if (edid_size(fwdata, fwsize) != fwsize) {

		DRM_ERROR("Size of EDID firmware \"%s\" is invalid "

		    "(expected %d, got %d)\n", name, expected, (int) fwsize);

		err = -EINVAL;

		goto relfw_out;

			  "(expected %d, got %d\n", name,

			  edid_size(fwdata, fwsize), (int)fwsize);

		edid = ERR_PTR(-EINVAL);

		goto out;

	}



	edid = kmemdup(fwdata, fwsize, GFP_KERNEL);

	if (edid == NULL) {

		err = -ENOMEM;

		goto relfw_out;

		edid = ERR_PTR(-ENOMEM);

		goto out;

	}



	if (!drm_edid_block_valid(edid, 0, print_bad_edid)) {
@@ -197,8 +202,8 @@ static u8 *edid_load(struct drm_connector *connector, const char *name, 
		DRM_ERROR("Base block of EDID firmware \"%s\" is invalid ",

		    name);

		kfree(edid);

		err = -EINVAL;

		goto relfw_out;

		edid = ERR_PTR(-EINVAL);

		goto out;

	}



	for (i = 1; i <= edid[0x7e]; i++) {
@@ -210,18 +215,17 @@ static u8 *edid_load(struct drm_connector *connector, const char *name, 
	}



	if (valid_extensions != edid[0x7e]) {

		u8 *new_edid;



		edid[EDID_LENGTH-1] += edid[0x7e] - valid_extensions;

		DRM_INFO("Found %d valid extensions instead of %d in EDID data "

		    "\"%s\" for connector \"%s\"\n", valid_extensions,

		    edid[0x7e], name, connector_name);

		edid[0x7e] = valid_extensions;



		new_edid = krealloc(edid, (valid_extensions + 1) * EDID_LENGTH,

				    GFP_KERNEL);

		if (new_edid == NULL) {

			err = -ENOMEM;

			kfree(edid);

			goto relfw_out;

		}

		if (new_edid)

			edid = new_edid;

	}
@@ -230,13 +234,9 @@ static u8 *edid_load(struct drm_connector *connector, const char *name, 
	    "external", valid_extensions, valid_extensions == 1 ? "" : "s",

	    name, connector_name);



relfw_out:

	release_firmware(fw);



out:

	if (err)

		return ERR_PTR(err);



	if (fw)

		release_firmware(fw);

	return edid;

}

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