[PATCH 5/8] drm/i915/huc: Support HuC authentication

[Anusha Srivatsa]

From: Peter Antoine <peter.antoine at intel.com>

The HuC authentication is done by host2guc call. The HuC RSA keys
are sent to GuC for authentication.

v2: rebased on top of drm-intel-nightly.
    changed name format and upped version 1.7.
v3: rebased on top of drm-intel-nightly.
v4: changed wait_for_automic to wait_for
v5: rebased.
v7: rebased.
v8: rebased.

Tested-by: Xiang Haihao <haihao.xiang at intel.com>
Signed-off-by: Anusha Srivatsa <anusha.srivatsa at intel.com>
Signed-off-by: Alex Dai <yu.dai at intel.com>
Signed-off-by: Peter Antoine <peter.antoine at intel.com>
Reviewed-by: Dave Gordon <david.s.gordon at intel.com>
---
 drivers/gpu/drm/i915/i915_guc_submission.c | 65 ++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/intel_guc_fwif.h      |  1 +
 drivers/gpu/drm/i915/intel_guc_loader.c    |  2 +
 3 files changed, 68 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
index 4b92943..984b529 100644
--- a/drivers/gpu/drm/i915/i915_guc_submission.c
+++ b/drivers/gpu/drm/i915/i915_guc_submission.c
@@ -25,6 +25,7 @@
 #include <linux/circ_buf.h>
 #include "i915_drv.h"
 #include "intel_guc.h"
+#include "intel_huc.h"
 
 /**
  * DOC: GuC-based command submission
@@ -1110,3 +1111,67 @@ int intel_guc_resume(struct drm_device *dev)
 
 	return host2guc_action(guc, data, ARRAY_SIZE(data));
 }
+
+/**
+ * intel_huc_auth() - authenticate ucode
+ * @dev: the drm device
+ *
+ * Triggers a HuC fw authentication request to the GuC via host-2-guc
+ * interface.
+ */
+void intel_huc_auth(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_guc *guc = &dev_priv->guc;
+	struct intel_huc *huc = &dev_priv->huc;
+	struct i915_vma *vma;
+	int ret;
+	u32 data[2];
+
+	/* Bypass the case where there is no HuC firmware */
+	if (huc->huc_fw.fetch_status == UC_FIRMWARE_NONE ||
+	    huc->huc_fw.load_status == UC_FIRMWARE_NONE)
+		return;
+
+	if (guc->guc_fw.load_status != UC_FIRMWARE_SUCCESS) {
+		DRM_ERROR("HuC: GuC fw wasn't loaded. Can't authenticate");
+		return;
+	}
+
+	if (huc->huc_fw.load_status != UC_FIRMWARE_SUCCESS) {
+		DRM_ERROR("HuC: fw wasn't loaded. Nothing to authenticate");
+		return;
+	}
+
+	vma = i915_gem_object_ggtt_pin(huc->huc_fw.uc_fw_obj, NULL, 0, 0, 0);
+	if (IS_ERR(vma)) {
+		DRM_DEBUG_DRIVER("pin failed %d\n", (int)PTR_ERR(vma));
+		return;
+	}
+
+
+	/* Invalidate GuC TLB to let GuC take the latest updates to GTT. */
+	I915_WRITE(GEN8_GTCR, GEN8_GTCR_INVALIDATE);
+
+	/* Specify auth action and where public signature is. It's stored
+	 * at the beginning of the gem object, before the fw bits
+	 */
+	data[0] = HOST2GUC_ACTION_AUTHENTICATE_HUC;
+	data[1] = i915_ggtt_offset(vma) + huc->huc_fw.rsa_offset;
+
+	ret = host2guc_action(guc, data, ARRAY_SIZE(data));
+	if (ret) {
+		DRM_ERROR("HuC: GuC did not ack Auth request\n");
+		goto out;
+	}
+
+	/* Check authentication status, it should be done by now */
+	ret = wait_for((I915_READ(HUC_STATUS2) & HUC_FW_VERIFIED) > 0, 50);
+	if (ret) {
+		DRM_ERROR("HuC: Authentication failed\n");
+		goto out;
+	}
+
+out:
+	i915_vma_unpin(vma);
+}
diff --git a/drivers/gpu/drm/i915/intel_guc_fwif.h b/drivers/gpu/drm/i915/intel_guc_fwif.h
index b38b6b4..57e6466 100644
--- a/drivers/gpu/drm/i915/intel_guc_fwif.h
+++ b/drivers/gpu/drm/i915/intel_guc_fwif.h
@@ -438,6 +438,7 @@ enum host2guc_action {
 	HOST2GUC_ACTION_ENTER_S_STATE = 0x501,
 	HOST2GUC_ACTION_EXIT_S_STATE = 0x502,
 	HOST2GUC_ACTION_SLPC_REQUEST = 0x3003,
+	HOST2GUC_ACTION_AUTHENTICATE_HUC = 0x4000,
 	HOST2GUC_ACTION_LIMIT
 };
 
diff --git a/drivers/gpu/drm/i915/intel_guc_loader.c b/drivers/gpu/drm/i915/intel_guc_loader.c
index 0d214b4..31a2b0a 100644
--- a/drivers/gpu/drm/i915/intel_guc_loader.c
+++ b/drivers/gpu/drm/i915/intel_guc_loader.c
@@ -527,6 +527,8 @@ int intel_guc_setup(struct drm_device *dev)
 		intel_uc_fw_status_repr(guc_fw->fetch_status),
 		intel_uc_fw_status_repr(guc_fw->load_status));
 
+	intel_huc_auth(dev);
+
 	if (i915.enable_guc_submission) {
 		err = i915_guc_submission_enable(dev_priv);
 		if (err)
-- 
2.7.4