drm/msm: Implement HDCP 1.x using the new drm HDCP helpers

This patch adds HDCP 1.x support to msm DP connectors using the new HDCP
helpers.

Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Abhinav Kumar <abhinavk@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210913175747.47456-15-sean@poorly.run #v1
Link: https://patchwork.freedesktop.org/patch/msgid/20210915203834.1439-14-sean@poorly.run #v2
Link: https://patchwork.freedesktop.org/patch/msgid/20211001151145.55916-15-sean@poorly.run #v3
Link: https://patchwork.freedesktop.org/patch/msgid/20211105030434.2828845-15-sean@poorly.run #v4

Changes in v2:
-Squash [1] into this patch with the following changes (Stephen)
  -Update the sc7180 dtsi file
  -Remove resource names and just use index (Stephen)
Changes in v3:
-Split out the dtsi change from v2 (Stephen)
-Fix set-but-unused warning identified by 0-day
-Fix up a couple of style nits (Stephen)
-Store HDCP key directly in dp_hdcp struct (Stephen)
-Remove wmb in HDCP key initialization, move an_seed (Stephen)
-Use FIELD_PREP for bstatus/bcaps (Stephen)
-#define read_poll_timeout values (Stephen)
-Remove unnecessary parentheses in dp_hdcp_store_ksv_fifo (Stephen)
-Add compatible string for hdcp (Stephen)
-Rename dp_hdcp_write_* functions (Abhinav)
-Add 1us delay between An reads (Abhinav)
-Delete unused dp_hdcp_read_* functions
Changes in v4:
-Rebase on Bjorn's multi-dp patchset
Changes in v5:
-Change return check of drm_hdcp_helper_initialize_dp() (Stephen)

[1] https://patchwork.freedesktop.org/patch/msgid/20210913175747.47456-14-sean@poorly.run

drivers/gpu/drm/msm/Makefile

@@ -106,6 +106,7 @@ msm-$(CONFIG_DRM_MSM_DP)+= dp/dp_aux.o \
 	dp/dp_ctrl.o \
 	dp/dp_display.o \
 	dp/dp_drm.o \
+	dp/dp_hdcp.o \
 	dp/dp_hpd.o \
 	dp/dp_link.o \
 	dp/dp_panel.o \

drivers/gpu/drm/msm/dp/dp_debug.c

@@ -8,13 +8,15 @@
 #include <linux/debugfs.h>
 #include <drm/drm_connector.h>
 #include <drm/drm_file.h>
+#include <drm/drm_hdcp.h>
 
 #include "dp_parser.h"
 #include "dp_catalog.h"
 #include "dp_aux.h"
 #include "dp_ctrl.h"
 #include "dp_debug.h"
 #include "dp_display.h"
+#include "dp_hdcp.h"
 
 #define DEBUG_NAME "msm_dp"
 
@@ -25,6 +27,7 @@ struct dp_debug_private {
 	struct dp_link *link;
 	struct dp_panel *panel;
 	struct drm_connector *connector;
+	struct dp_hdcp *hdcp;
 	struct device *dev;
 	struct drm_device *drm_dev;
 
@@ -198,6 +201,35 @@ static int dp_test_active_open(struct inode *inode,
 			inode->i_private);
 }
 
+static ssize_t dp_hdcp_key_write(struct file *file, const char __user *ubuf,
+				 size_t len, loff_t *offp)
+{
+	char *input_buffer;
+	int ret;
+	struct dp_debug_private *debug = file->private_data;
+
+	if (len != (DRM_HDCP_KSV_LEN + DP_HDCP_NUM_KEYS * DP_HDCP_KEY_LEN))
+		return -EINVAL;
+
+	if (!debug->hdcp)
+		return -ENOENT;
+
+	input_buffer = memdup_user_nul(ubuf, len);
+	if (IS_ERR(input_buffer))
+		return PTR_ERR(input_buffer);
+
+	ret = dp_hdcp_ingest_key(debug->hdcp, input_buffer, len);
+
+	kfree(input_buffer);
+	if (ret < 0) {
+		DRM_ERROR("Could not ingest HDCP key, ret=%d\n", ret);
+		return ret;
+	}
+
+	*offp += len;
+	return len;
+}
+
 static const struct file_operations test_active_fops = {
 	.owner = THIS_MODULE,
 	.open = dp_test_active_open,
@@ -207,6 +239,12 @@ static const struct file_operations test_active_fops = {
 	.write = dp_test_active_write
 };
 
+static const struct file_operations dp_hdcp_key_fops = {
+	.owner = THIS_MODULE,
+	.open = simple_open,
+	.write = dp_hdcp_key_write,
+};
+
 static void dp_debug_init(struct dp_debug *dp_debug, struct drm_minor *minor)
 {
 	char path[64];
@@ -231,11 +269,16 @@ static void dp_debug_init(struct dp_debug *dp_debug, struct drm_minor *minor)
 	debugfs_create_file("msm_dp_test_type", 0444,
 			debug->root,
 			debug, &dp_test_type_fops);
+
+	debugfs_create_file("msm_dp_hdcp_key", 0222,
+			minor->debugfs_root,
+			debug, &dp_hdcp_key_fops);
 }
 
 struct dp_debug *dp_debug_get(struct device *dev, struct dp_panel *panel,
 		struct dp_usbpd *usbpd, struct dp_link *link,
-		struct drm_connector *connector, struct drm_minor *minor)
+		struct dp_hdcp *hdcp, struct drm_connector *connector,
+		struct drm_minor *minor)
 {
 	struct dp_debug_private *debug;
 	struct dp_debug *dp_debug;
@@ -257,6 +300,7 @@ struct dp_debug *dp_debug_get(struct device *dev, struct dp_panel *panel,
 	debug->usbpd = usbpd;
 	debug->link = link;
 	debug->panel = panel;
+	debug->hdcp = hdcp;
 	debug->dev = dev;
 	debug->drm_dev = minor->dev;
 	debug->connector = connector;

drivers/gpu/drm/msm/dp/dp_debug.h

@@ -6,6 +6,7 @@
 #ifndef _DP_DEBUG_H_
 #define _DP_DEBUG_H_
 
+#include "dp_hdcp.h"
 #include "dp_panel.h"
 #include "dp_link.h"
 
@@ -43,7 +44,7 @@ struct dp_debug {
  */
 struct dp_debug *dp_debug_get(struct device *dev, struct dp_panel *panel,
 		struct dp_usbpd *usbpd, struct dp_link *link,
-		struct drm_connector *connector,
+		struct dp_hdcp *hdcp, struct drm_connector *connector,
 		struct drm_minor *minor);
 
 /**
@@ -60,7 +61,8 @@ void dp_debug_put(struct dp_debug *dp_debug);
 static inline
 struct dp_debug *dp_debug_get(struct device *dev, struct dp_panel *panel,
 		struct dp_usbpd *usbpd, struct dp_link *link,
-		struct drm_connector *connector, struct drm_minor *minor)
+		struct dp_hdcp *hdcp, struct drm_connector *connector,
+		struct drm_minor *minor)
 {
 	return ERR_PTR(-EINVAL);
 }

drivers/gpu/drm/msm/dp/dp_display.c

@@ -27,6 +27,7 @@
 #include "dp_drm.h"
 #include "dp_audio.h"
 #include "dp_debug.h"
+#include "dp_hdcp.h"
 
 #define HPD_STRING_SIZE 30
 
@@ -99,6 +100,7 @@ struct dp_display_private {
 	struct dp_panel   *panel;
 	struct dp_ctrl    *ctrl;
 	struct dp_debug   *debug;
+	struct dp_hdcp	  *hdcp;
 
 	struct dp_usbpd_cb usbpd_cb;
 	struct dp_display_mode dp_mode;
@@ -177,6 +179,15 @@ static struct dp_display_private *dev_get_dp_display_private(struct device *dev)
 	return container_of(dp, struct dp_display_private, dp_display);
 }
 
+struct dp_hdcp *dp_display_connector_to_hdcp(struct drm_connector *connector)
+{
+	struct msm_dp *dp_display = msm_dp_from_connector(connector);
+	struct dp_display_private *dp;
+
+	dp = container_of(dp_display, struct dp_display_private, dp_display);
+	return dp->hdcp;
+}
+
 static int dp_add_event(struct dp_display_private *dp_priv, u32 event,
 						u32 data, u32 delay)
 {
@@ -749,6 +760,7 @@ static int dp_irq_hpd_handle(struct dp_display_private *dp, u32 data)
 static void dp_display_deinit_sub_modules(struct dp_display_private *dp)
 {
 	dp_debug_put(dp->debug);
+	dp_hdcp_put(dp->hdcp);
 	dp_audio_put(dp->audio);
 	dp_panel_put(dp->panel);
 	dp_aux_put(dp->aux);
@@ -845,8 +857,18 @@ static int dp_init_sub_modules(struct dp_display_private *dp)
 		goto error_ctrl;
 	}
 
+	dp->hdcp = dp_hdcp_get(dp->parser, dp->aux);
+	if (IS_ERR(dp->hdcp)) {
+		rc = PTR_ERR(dp->hdcp);
+		DRM_ERROR("failed to initialize hdcp, rc = %d\n", rc);
+		dp->hdcp = NULL;
+		goto error_hdcp;
+	}
+
 	return rc;
 
+error_hdcp:
+	dp_audio_put(dp->audio);
 error_ctrl:
 	dp_panel_put(dp->panel);
 error_link:
@@ -968,6 +990,16 @@ int dp_display_set_plugged_cb(struct msm_dp *dp_display,
 	return 0;
 }
 
+void dp_display_hdcp_commit(struct msm_dp *dp, struct drm_atomic_state *state)
+{
+	struct dp_display_private *dp_display;
+
+	dp_display = container_of(dp, struct dp_display_private, dp_display);
+
+	if (dp_display->hdcp)
+		dp_hdcp_commit(dp_display->hdcp, state);
+}
+
 int dp_display_validate_mode(struct msm_dp *dp, u32 mode_pclk_khz)
 {
 	const u32 num_components = 3, default_bpp = 24;
@@ -1498,8 +1530,8 @@ void msm_dp_debugfs_init(struct msm_dp *dp_display, struct drm_minor *minor)
 	dev = &dp->pdev->dev;
 
 	dp->debug = dp_debug_get(dev, dp->panel, dp->usbpd,
-					dp->link, dp->dp_display.connector,
-					minor);
+					dp->link, dp->hdcp,
+					dp->dp_display.connector, minor);
 	if (IS_ERR(dp->debug)) {
 		rc = PTR_ERR(dp->debug);
 		DRM_ERROR("failed to initialize debug, rc = %d\n", rc);
@@ -1510,13 +1542,17 @@ void msm_dp_debugfs_init(struct msm_dp *dp_display, struct drm_minor *minor)
 int msm_dp_modeset_init(struct msm_dp *dp_display, struct drm_device *dev,
 			struct drm_encoder *encoder)
 {
+	struct dp_display_private *dp_display_priv;
 	struct msm_drm_private *priv;
 	struct dp_display_private *dp_priv;
 	int ret;
 
 	if (WARN_ON(!encoder) || WARN_ON(!dp_display) || WARN_ON(!dev))
 		return -EINVAL;
 
+	dp_display_priv = container_of(dp_display, struct dp_display_private,
+				       dp_display);
+
 	priv = dev->dev_private;
 	dp_display->drm_dev = dev;
 
@@ -1541,6 +1577,12 @@ int msm_dp_modeset_init(struct msm_dp *dp_display, struct drm_device *dev,
 
 	dp_priv->panel->connector = dp_display->connector;
 
+	ret = dp_hdcp_attach(dp_display_priv->hdcp, dp_display->connector);
+	if (ret) {
+		DRM_ERROR("Failed to attach hdcp, ret=%d\n", ret);
+		return ret;
+	}
+
 	priv->connectors[priv->num_connectors++] = dp_display->connector;
 
 	dp_display->bridge = msm_dp_bridge_init(dp_display, dev, encoder);

drivers/gpu/drm/msm/dp/dp_display.h

@@ -30,8 +30,13 @@ struct msm_dp {
 	struct dp_audio *dp_audio;
 };
 
+struct drm_atomic_state;
+
 int dp_display_set_plugged_cb(struct msm_dp *dp_display,
 		hdmi_codec_plugged_cb fn, struct device *codec_dev);
+struct dp_hdcp *dp_display_connector_to_hdcp(struct drm_connector *connector);
+void dp_display_hdcp_commit(struct msm_dp *dp_display,
+			    struct drm_atomic_state *state);
 int dp_display_validate_mode(struct msm_dp *dp_display, u32 mode_pclk_khz);
 int dp_display_get_modes(struct msm_dp *dp_display,
 		struct dp_display_mode *dp_mode);

drivers/gpu/drm/msm/dp/dp_drm.c

@@ -6,11 +6,20 @@
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_atomic.h>
 #include <drm/drm_bridge.h>
+#include <drm/drm_connector.h>
 #include <drm/drm_crtc.h>
+#include <drm/drm_hdcp.h>
 
 #include "msm_drv.h"
 #include "msm_kms.h"
 #include "dp_drm.h"
+#include "dp_hdcp.h"
+
+struct dp_connector_state {
+	struct drm_connector_state base;
+	bool hdcp_transition;
+};
+#define to_dp_connector_state(x) container_of(x, struct dp_connector_state, base)
 
 
 struct msm_dp_bridge {
@@ -26,6 +35,11 @@ struct dp_connector {
 };
 #define to_dp_connector(x) container_of(x, struct dp_connector, base)
 
+struct msm_dp *msm_dp_from_connector(struct drm_connector *connector)
+{
+	return to_dp_connector(connector)->dp_display;
+}
+
 /**
  * dp_connector_detect - callback to determine if connector is connected
  * @conn: Pointer to drm connector structure
@@ -123,20 +137,72 @@ static enum drm_mode_status dp_connector_mode_valid(
 	return dp_display_validate_mode(dp_disp, mode->clock);
 }
 
+static int dp_connector_atomic_check(struct drm_connector *connector,
+				     struct drm_atomic_state *state)
+{
+	struct drm_connector_state *conn_state;
+	struct dp_connector_state *dp_state;
+
+	conn_state = drm_atomic_get_new_connector_state(state, connector);
+	dp_state = to_dp_connector_state(conn_state);
+
+	dp_state->hdcp_transition = drm_hdcp_atomic_check(connector, state);
+
+	return 0;
+}
+
+static struct drm_connector_state *
+dp_connector_atomic_duplicate_state(struct drm_connector *connector)
+{
+	struct dp_connector_state *state;
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (!state)
+		return NULL;
+
+	state->hdcp_transition = false;
+
+	__drm_atomic_helper_connector_duplicate_state(connector, &state->base);
+	return &state->base;
+}
+
 static const struct drm_connector_funcs dp_connector_funcs = {
 	.detect = dp_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = drm_connector_cleanup,
 	.reset = drm_atomic_helper_connector_reset,
-	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_duplicate_state = dp_connector_atomic_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 };
 
 static const struct drm_connector_helper_funcs dp_connector_helper_funcs = {
 	.get_modes = dp_connector_get_modes,
 	.mode_valid = dp_connector_mode_valid,
+	.atomic_check = dp_connector_atomic_check,
 };
 
+bool dp_drm_is_connector_msm_dp(struct drm_connector *connector)
+{
+	return connector->funcs == &dp_connector_funcs;
+}
+
+void dp_drm_atomic_commit(struct drm_connector *connector,
+			  struct drm_connector_state *conn_state,
+			  struct drm_atomic_state *state)
+{
+	struct dp_connector_state *dp_state;
+	struct msm_dp *dp_disp;
+
+	dp_state = to_dp_connector_state(conn_state);
+
+	if (!dp_state->hdcp_transition)
+		return;
+
+	dp_disp = msm_dp_from_connector(connector);
+
+	dp_display_hdcp_commit(dp_disp, state);
+}
+
 /* connector initialization */
 struct drm_connector *dp_drm_connector_init(struct msm_dp *dp_display)
 {

drivers/gpu/drm/msm/dp/dp_drm.h

@@ -14,5 +14,10 @@
 #include "dp_display.h"
 
 struct drm_connector *dp_drm_connector_init(struct msm_dp *dp_display);
+struct msm_dp *msm_dp_from_connector(struct drm_connector *connector);
+bool dp_drm_is_connector_msm_dp(struct drm_connector *connector);
+void dp_drm_atomic_commit(struct drm_connector *connector,
+			  struct drm_connector_state *conn_state,
+			  struct drm_atomic_state *state);
 
 #endif /* _DP_DRM_H_ */