Commit b3e4aae6 authored by Suraj Kandpal's avatar Suraj Kandpal Committed by Ankit Nautiyal
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drm/i915/hdcp: Modify hdcp_gsc_message msg sending mechanism 

Allocate a multipage object that can be used for input
and output for intel_hdcp_gsc_message so that corruption of
output message can be avoided by the current overwriting method.
Modify intel_gsc_send_sync() to take into account header_out
and addr_out so as to use them to verify the message send status.
Check link for comment and review history
https://patchwork.freedesktop.org/series/118499/



--v2
-Change approach from allocating two objects to just one multipage
object [Daniele]

--v3
-Squash the two patches together [Daniele]
-No need to allocate twice the size of intel_hdcp_gsc_message [Daniele]

Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Cc: Alan Previn <alan.previn.teres.alexis@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: default avatarSuraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: default avatarDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: default avatarAnkit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230602105113.1791104-1-suraj.kandpal@intel.com
parent 19a49f39

drivers/gpu/drm/i915/display/intel_hdcp_gsc.c

+47 −33
Original line number Diff line number Diff line
@@ -621,24 +621,26 @@ static int intel_hdcp_gsc_initialize_message(struct drm_i915_private *i915, 
	struct intel_gt *gt = i915->media_gt;

	struct drm_i915_gem_object *obj = NULL;

	struct i915_vma *vma = NULL;

	void *cmd;

	void *cmd_in, *cmd_out;

	int err;



	/* allocate object of one page for HDCP command memory and store it */

	obj = i915_gem_object_create_shmem(i915, PAGE_SIZE);

	/* allocate object of two page for HDCP command memory and store it */

	obj = i915_gem_object_create_shmem(i915, 2 * PAGE_SIZE);



	if (IS_ERR(obj)) {

		drm_err(&i915->drm, "Failed to allocate HDCP streaming command!\n");

		return PTR_ERR(obj);

	}



	cmd = i915_gem_object_pin_map_unlocked(obj, i915_coherent_map_type(i915, obj, true));

	if (IS_ERR(cmd)) {

	cmd_in = i915_gem_object_pin_map_unlocked(obj, i915_coherent_map_type(i915, obj, true));

	if (IS_ERR(cmd_in)) {

		drm_err(&i915->drm, "Failed to map gsc message page!\n");

		err = PTR_ERR(cmd);

		err = PTR_ERR(cmd_in);

		goto out_unpin;

	}



	cmd_out = cmd_in + PAGE_SIZE;



	vma = i915_vma_instance(obj, &gt->ggtt->vm, NULL);

	if (IS_ERR(vma)) {

		err = PTR_ERR(vma);
@@ -649,9 +651,10 @@ static int intel_hdcp_gsc_initialize_message(struct drm_i915_private *i915, 
	if (err)

		goto out_unmap;



	memset(cmd, 0, obj->base.size);

	memset(cmd_in, 0, obj->base.size);



	hdcp_message->hdcp_cmd = cmd;

	hdcp_message->hdcp_cmd_in = cmd_in;

	hdcp_message->hdcp_cmd_out = cmd_out;

	hdcp_message->vma = vma;



	return 0;
@@ -691,6 +694,8 @@ static void intel_hdcp_gsc_free_message(struct drm_i915_private *i915) 
	struct intel_hdcp_gsc_message *hdcp_message =

					i915->display.hdcp.hdcp_message;



	hdcp_message->hdcp_cmd_in = NULL;

	hdcp_message->hdcp_cmd_out = NULL;

	i915_vma_unpin_and_release(&hdcp_message->vma, I915_VMA_RELEASE_MAP);

	kfree(hdcp_message);

}
@@ -721,38 +726,42 @@ void intel_hdcp_gsc_fini(struct drm_i915_private *i915) 
}



static int intel_gsc_send_sync(struct drm_i915_private *i915,

			       struct intel_gsc_mtl_header *header, u64 addr,

			       struct intel_gsc_mtl_header *header_in,

			       struct intel_gsc_mtl_header *header_out,

			       u64 addr_in, u64 addr_out,

			       size_t msg_out_len)

{

	struct intel_gt *gt = i915->media_gt;

	int ret;



	header->flags = 0;

	ret = intel_gsc_uc_heci_cmd_submit_packet(&gt->uc.gsc, addr,

						  header->message_size,

						  addr,

						  msg_out_len + sizeof(*header));

	ret = intel_gsc_uc_heci_cmd_submit_packet(&gt->uc.gsc, addr_in,

						  header_in->message_size,

						  addr_out,

						  msg_out_len + sizeof(*header_out));

	if (ret) {

		drm_err(&i915->drm, "failed to send gsc HDCP msg (%d)\n", ret);

		return ret;

	}



	/*

	 * Checking validity marker for memory sanity

	 * Checking validity marker and header status to see if some error has

	 * blocked us from sending message to gsc cs

	 */

	if (header->validity_marker != GSC_HECI_VALIDITY_MARKER) {

	if (header_out->validity_marker != GSC_HECI_VALIDITY_MARKER) {

		drm_err(&i915->drm, "invalid validity marker\n");

		return -EINVAL;

	}



	if (header->status != 0) {

	if (header_out->status != 0) {

		drm_err(&i915->drm, "header status indicates error %d\n",

			header->status);

			header_out->status);

		return -EINVAL;

	}



	if (header->flags & GSC_OUTFLAG_MSG_PENDING)

	if (header_out->flags & GSC_OUTFLAG_MSG_PENDING) {

		header_in->gsc_message_handle = header_out->gsc_message_handle;

		return -EAGAIN;

	}



	return 0;

}
@@ -769,11 +778,11 @@ ssize_t intel_hdcp_gsc_msg_send(struct drm_i915_private *i915, u8 *msg_in, 
				size_t msg_out_len)

{

	struct intel_gt *gt = i915->media_gt;

	struct intel_gsc_mtl_header *header;

	const size_t max_msg_size = PAGE_SIZE - sizeof(*header);

	struct intel_gsc_mtl_header *header_in, *header_out;

	const size_t max_msg_size = PAGE_SIZE - sizeof(*header_in);

	struct intel_hdcp_gsc_message *hdcp_message;

	u64 addr, host_session_id;

	u32 reply_size, msg_size;

	u64 addr_in, addr_out, host_session_id;

	u32 reply_size, msg_size_in, msg_size_out;

	int ret, tries = 0;



	if (!intel_uc_uses_gsc_uc(&gt->uc))
@@ -782,16 +791,20 @@ ssize_t intel_hdcp_gsc_msg_send(struct drm_i915_private *i915, u8 *msg_in, 
	if (msg_in_len > max_msg_size || msg_out_len > max_msg_size)

		return -ENOSPC;



	msg_size_in = msg_in_len + sizeof(*header_in);

	msg_size_out = msg_out_len + sizeof(*header_out);

	hdcp_message = i915->display.hdcp.hdcp_message;

	header = hdcp_message->hdcp_cmd;

	addr = i915_ggtt_offset(hdcp_message->vma);

	header_in = hdcp_message->hdcp_cmd_in;

	header_out = hdcp_message->hdcp_cmd_out;

	addr_in = i915_ggtt_offset(hdcp_message->vma);

	addr_out = addr_in + PAGE_SIZE;



	msg_size = msg_in_len + sizeof(*header);

	memset(header, 0, msg_size);

	memset(header_in, 0, msg_size_in);

	memset(header_out, 0, msg_size_out);

	get_random_bytes(&host_session_id, sizeof(u64));

	intel_gsc_uc_heci_cmd_emit_mtl_header(header, HECI_MEADDRESS_HDCP,

					      msg_size, host_session_id);

	memcpy(hdcp_message->hdcp_cmd + sizeof(*header), msg_in, msg_in_len);

	intel_gsc_uc_heci_cmd_emit_mtl_header(header_in, HECI_MEADDRESS_HDCP,

					      msg_size_in, host_session_id);

	memcpy(hdcp_message->hdcp_cmd_in + sizeof(*header_in), msg_in, msg_in_len);



	/*

	 * Keep sending request in case the pending bit is set no need to add
@@ -800,7 +813,8 @@ ssize_t intel_hdcp_gsc_msg_send(struct drm_i915_private *i915, u8 *msg_in, 
	 * 20 times each message 50 ms apart

	 */

	do {

		ret = intel_gsc_send_sync(i915, header, addr, msg_out_len);

		ret = intel_gsc_send_sync(i915, header_in, header_out, addr_in,

					  addr_out, msg_out_len);



		/* Only try again if gsc says so */

		if (ret != -EAGAIN)
@@ -814,7 +828,7 @@ ssize_t intel_hdcp_gsc_msg_send(struct drm_i915_private *i915, u8 *msg_in, 
		goto err;



	/* we use the same mem for the reply, so header is in the same loc */

	reply_size = header->message_size - sizeof(*header);

	reply_size = header_out->message_size - sizeof(*header_out);

	if (reply_size > msg_out_len) {

		drm_warn(&i915->drm, "caller with insufficient HDCP reply size %u (%d)\n",

			 reply_size, (u32)msg_out_len);
@@ -824,7 +838,7 @@ ssize_t intel_hdcp_gsc_msg_send(struct drm_i915_private *i915, u8 *msg_in, 
			    reply_size, (u32)msg_out_len);

	}



	memcpy(msg_out, hdcp_message->hdcp_cmd + sizeof(*header), msg_out_len);

	memcpy(msg_out, hdcp_message->hdcp_cmd_out + sizeof(*header_out), msg_out_len);



err:

	return ret;

drivers/gpu/drm/i915/display/intel_hdcp_gsc.h

+2 −1
Original line number Diff line number Diff line
@@ -13,7 +13,8 @@ struct drm_i915_private; 


struct intel_hdcp_gsc_message {

	struct i915_vma *vma;

	void *hdcp_cmd;

	void *hdcp_cmd_in;

	void *hdcp_cmd_out;

};



bool intel_hdcp_gsc_cs_required(struct drm_i915_private *i915);