[PATCH 05/49] drm/amd/display: Add KUnit tests for HDCP display helpers

[Fangzhi Zuo <jerry.zuo@amd.com>]

From: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>

Cover the HDCP display lifecycle helpers:
- hdcp_update_display() registers the connector and, on the
  disable path, resets the per-link encryption status to
  HDCP_OFF.
- hdcp_remove_display() reverts an ENABLED connector back to
  DESIRED and clears the per-link entry, including the NULL
  connector-state path.
- hdcp_reset_display() clears the encryption status and the
  connector for every link.

Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Signed-off-by: Fangzhi Zuo <jerry.zuo@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
---
 .../amd/display/amdgpu_dm/amdgpu_dm_hdcp.c    |   6 +-
 .../amd/display/amdgpu_dm/amdgpu_dm_hdcp.h    |   2 +
 .../amdgpu_dm/tests/amdgpu_dm_hdcp_test.c     | 207 ++++++++++++++++++
 3 files changed, 214 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
index 3b5e0e64adde..f786c0a85425 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
@@ -317,8 +317,10 @@ void hdcp_update_display(struct hdcp_workqueue *hdcp_work,
 
 	process_output(hdcp_w);
 }
+EXPORT_IF_KUNIT(hdcp_update_display);
 
-static void hdcp_remove_display(struct hdcp_workqueue *hdcp_work,
+STATIC_IFN_KUNIT
+void hdcp_remove_display(struct hdcp_workqueue *hdcp_work,
 				unsigned int link_index,
 			 struct amdgpu_dm_connector *aconnector)
 {
@@ -348,6 +350,7 @@ static void hdcp_remove_display(struct hdcp_workqueue *hdcp_work,
 	}
 	process_output(hdcp_w);
 }
+EXPORT_IF_KUNIT(hdcp_remove_display);
 
 void hdcp_reset_display(struct hdcp_workqueue *hdcp_work, unsigned int link_index)
 {
@@ -371,6 +374,7 @@ void hdcp_reset_display(struct hdcp_workqueue *hdcp_work, unsigned int link_inde
 
 	process_output(hdcp_w);
 }
+EXPORT_IF_KUNIT(hdcp_reset_display);
 
 void hdcp_handle_cpirq(struct hdcp_workqueue *hdcp_work, unsigned int link_index)
 {
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.h
index fb66f48d7297..69a50e081c56 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.h
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.h
@@ -115,6 +115,8 @@ void hdcp_update_display_encryption_control(struct hdcp_workqueue *hdcp_work,
 					    bool enable_encryption);
 void event_property_update(struct work_struct *work);
 void link_lock(struct hdcp_workqueue *work, bool lock);
+void hdcp_remove_display(struct hdcp_workqueue *hdcp_work, unsigned int link_index,
+			 struct amdgpu_dm_connector *aconnector);
 uint8_t *psp_get_srm(struct psp_context *psp, uint32_t *srm_version, uint32_t *srm_size);
 int psp_set_srm(struct psp_context *psp, u8 *srm, uint32_t srm_size, uint32_t *srm_version);
 #endif
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_hdcp_test.c b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_hdcp_test.c
index 43c7efcdd22c..e6d03199187b 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_hdcp_test.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_hdcp_test.c
@@ -9,6 +9,7 @@
 #include <linux/workqueue.h>
 
 #include "amdgpu.h"
+#include "amdgpu_dm.h"
 #include "amdgpu_dm_hdcp.h"
 
 static void dummy_work_fn(struct work_struct *work) {}
@@ -753,6 +754,206 @@ static void dm_test_psp_set_srm_uninitialized_returns_einval(struct kunit *test)
 
 /* End of tests for psp_get_srm() and psp_set_srm() */
 
+/*
+ * Tests for hdcp_update_display() / hdcp_remove_display() /
+ * hdcp_reset_display().
+ */
+
+/**
+ * alloc_test_workqueue_locked - workqueue with dworks and mutex initialised
+ * @test: KUnit test context for managed allocation
+ *
+ * Allocates a minimal hdcp_workqueue with its mutex and the three delayed
+ * works initialised, as required by the guard(mutex) and process_output()
+ * usage in the display update/remove/reset helpers.
+ */
+static struct hdcp_workqueue *alloc_test_workqueue_locked(struct kunit *test)
+{
+	struct hdcp_workqueue *work;
+
+	work = kunit_kzalloc(test, sizeof(*work), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, work);
+
+	mutex_init(&work->mutex);
+	INIT_DELAYED_WORK(&work->callback_dwork, dummy_work_fn);
+	INIT_DELAYED_WORK(&work->watchdog_timer_dwork, dummy_work_fn);
+	INIT_DELAYED_WORK(&work->property_validate_dwork, dummy_work_fn);
+
+	return work;
+}
+
+/**
+ * alloc_test_connector - minimal amdgpu_dm_connector for display tests
+ * @test: KUnit test context for managed allocation
+ * @index: drm connector index to assign
+ *
+ * Allocates an amdgpu_dm_connector with an initialised connector refcount
+ * (so drm_connector_get() is valid) and a dc_link/dc pair. The connector's
+ * free_cb is left NULL so drm_connector_put() is a safe no-op that never
+ * releases the object.
+ */
+static struct amdgpu_dm_connector *alloc_test_connector(struct kunit *test,
+							unsigned int index)
+{
+	struct amdgpu_dm_connector *aconnector;
+	struct dc_link *dc_link;
+	struct dc *dc;
+
+	aconnector = kunit_kzalloc(test, sizeof(*aconnector), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, aconnector);
+	dc_link = kunit_kzalloc(test, sizeof(*dc_link), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, dc_link);
+	dc = kunit_kzalloc(test, sizeof(*dc), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, dc);
+
+	kref_init(&aconnector->base.base.refcount);
+	aconnector->base.index = index;
+	dc_link->dc = dc;
+	aconnector->dc_link = dc_link;
+
+	return aconnector;
+}
+
+/**
+ * dm_test_hdcp_update_display_enable_registers_connector - enable stores the connector
+ * @test: KUnit test context
+ *
+ * hdcp_update_display() with enable_encryption=true should register the
+ * connector in the per-link aconnector array at its connector index. The
+ * hdcp has no active display, so mod_hdcp_update_display() is effectively a
+ * no-op and the call must not touch encryption_status.
+ */
+static void dm_test_hdcp_update_display_enable_registers_connector(struct kunit *test)
+{
+	struct hdcp_workqueue *work = alloc_test_workqueue_locked(test);
+	struct amdgpu_dm_connector *aconnector = alloc_test_connector(test, 0);
+
+	work->srm_size = 0;
+
+	hdcp_update_display(work, 0, aconnector, DRM_MODE_HDCP_CONTENT_TYPE0, true);
+
+	KUNIT_EXPECT_PTR_EQ(test, work->aconnector[0], aconnector);
+	KUNIT_EXPECT_EQ(test, work->encryption_status[0],
+			MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF);
+
+	cancel_delayed_work_sync(&work->property_validate_dwork);
+	cancel_delayed_work_sync(&work->callback_dwork);
+	cancel_delayed_work_sync(&work->watchdog_timer_dwork);
+}
+
+/**
+ * dm_test_hdcp_update_display_disable_sets_status_off - disable clears status
+ * @test: KUnit test context
+ *
+ * hdcp_update_display() with enable_encryption=false should register the
+ * connector and reset the connector's encryption_status entry to HDCP_OFF
+ * via hdcp_update_display_encryption_control().
+ */
+static void dm_test_hdcp_update_display_disable_sets_status_off(struct kunit *test)
+{
+	struct hdcp_workqueue *work = alloc_test_workqueue_locked(test);
+	struct amdgpu_dm_connector *aconnector = alloc_test_connector(test, 2);
+
+	work->encryption_status[2] = MOD_HDCP_ENCRYPTION_STATUS_HDCP2_TYPE1_ON;
+
+	hdcp_update_display(work, 0, aconnector, DRM_MODE_HDCP_CONTENT_TYPE0, false);
+
+	KUNIT_EXPECT_PTR_EQ(test, work->aconnector[2], aconnector);
+	KUNIT_EXPECT_EQ(test, work->encryption_status[2],
+			MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF);
+
+	cancel_delayed_work_sync(&work->property_validate_dwork);
+	cancel_delayed_work_sync(&work->callback_dwork);
+	cancel_delayed_work_sync(&work->watchdog_timer_dwork);
+}
+
+/**
+ * dm_test_hdcp_remove_display_enabled_resets_cp - ENABLED CP reverts to DESIRED
+ * @test: KUnit test context
+ *
+ * hdcp_remove_display() must revert a connector whose content_protection is
+ * ENABLED back to DESIRED and clear the per-link aconnector entry.
+ */
+static void dm_test_hdcp_remove_display_enabled_resets_cp(struct kunit *test)
+{
+	struct hdcp_workqueue *work = alloc_test_workqueue_locked(test);
+	struct amdgpu_dm_connector *aconnector = alloc_test_connector(test, 1);
+	struct drm_connector_state *conn_state;
+
+	conn_state = kunit_kzalloc(test, sizeof(*conn_state), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, conn_state);
+
+	conn_state->content_protection = DRM_MODE_CONTENT_PROTECTION_ENABLED;
+	aconnector->base.state = conn_state;
+	work->aconnector[1] = aconnector;
+
+	hdcp_remove_display(work, 0, aconnector);
+
+	KUNIT_EXPECT_EQ(test, conn_state->content_protection,
+			DRM_MODE_CONTENT_PROTECTION_DESIRED);
+	KUNIT_EXPECT_PTR_EQ(test, work->aconnector[1], NULL);
+
+	cancel_delayed_work_sync(&work->property_validate_dwork);
+	cancel_delayed_work_sync(&work->callback_dwork);
+	cancel_delayed_work_sync(&work->watchdog_timer_dwork);
+}
+
+/**
+ * dm_test_hdcp_remove_display_null_state_clears_connector - NULL state skips CP change
+ * @test: KUnit test context
+ *
+ * When the connector has no drm_connector_state, hdcp_remove_display() must
+ * skip the content_protection update path and still clear the per-link
+ * aconnector entry.
+ */
+static void dm_test_hdcp_remove_display_null_state_clears_connector(struct kunit *test)
+{
+	struct hdcp_workqueue *work = alloc_test_workqueue_locked(test);
+	struct amdgpu_dm_connector *aconnector = alloc_test_connector(test, 0);
+
+	aconnector->base.state = NULL;
+	work->aconnector[0] = aconnector;
+
+	hdcp_remove_display(work, 0, aconnector);
+
+	KUNIT_EXPECT_PTR_EQ(test, work->aconnector[0], NULL);
+
+	cancel_delayed_work_sync(&work->property_validate_dwork);
+	cancel_delayed_work_sync(&work->callback_dwork);
+	cancel_delayed_work_sync(&work->watchdog_timer_dwork);
+}
+
+/**
+ * dm_test_hdcp_reset_display_clears_all_state - reset clears status and connectors
+ * @test: KUnit test context
+ *
+ * hdcp_reset_display() must reset every connector's encryption_status to
+ * HDCP_OFF and clear all per-link aconnector entries.
+ */
+static void dm_test_hdcp_reset_display_clears_all_state(struct kunit *test)
+{
+	struct hdcp_workqueue *work = alloc_test_workqueue_locked(test);
+	struct amdgpu_dm_connector *aconnector = alloc_test_connector(test, 4);
+
+	work->encryption_status[4] = MOD_HDCP_ENCRYPTION_STATUS_HDCP2_TYPE1_ON;
+	work->aconnector[4] = aconnector;
+
+	hdcp_reset_display(work, 0);
+
+	KUNIT_EXPECT_EQ(test, work->encryption_status[4],
+			MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF);
+	KUNIT_EXPECT_PTR_EQ(test, work->aconnector[4], NULL);
+
+	cancel_delayed_work_sync(&work->property_validate_dwork);
+	cancel_delayed_work_sync(&work->callback_dwork);
+	cancel_delayed_work_sync(&work->watchdog_timer_dwork);
+}
+
+/*
+ * End of tests for hdcp_update_display() / hdcp_remove_display() /
+ * hdcp_reset_display().
+ */
+
 static struct kunit_case dm_hdcp_test_cases[] = {
 	/* hdcp_get_content_protection_from_status() */
 	KUNIT_CASE(dm_test_hdcp_get_cp_disabled_returns_desired),
@@ -790,6 +991,12 @@ static struct kunit_case dm_hdcp_test_cases[] = {
 	/* psp_get_srm() / psp_set_srm() */
 	KUNIT_CASE(dm_test_psp_get_srm_uninitialized_returns_null),
 	KUNIT_CASE(dm_test_psp_set_srm_uninitialized_returns_einval),
+	/* hdcp_update_display() / hdcp_remove_display() / hdcp_reset_display() */
+	KUNIT_CASE(dm_test_hdcp_update_display_enable_registers_connector),
+	KUNIT_CASE(dm_test_hdcp_update_display_disable_sets_status_off),
+	KUNIT_CASE(dm_test_hdcp_remove_display_enabled_resets_cp),
+	KUNIT_CASE(dm_test_hdcp_remove_display_null_state_clears_connector),
+	KUNIT_CASE(dm_test_hdcp_reset_display_clears_all_state),
 	{}
 };
 
-- 
2.53.0