drm/amd/display: HDCP Locality check using DMUB Fused IO

[Why]
HDCP locality check has strict timing requirements, currently broken
due to reliance on msleep which does not guarantee accuracy.
The PR moves the write-poll-read sequence into DMUB using new generic
Fused IO interface, where the timing accuracy is greatly improved.
New flow is enabled using DCN resource capability bit (none for now),
or using a debug flag.

[How]
* Extended mod_hdcp_config with new function for requesting DMUB
to execute a sequence of fused I2C/AUX commands and synchronously
wait until an outbox reply arrives or a timeout expires.
* If the timeout expires, send an abort to DMUB.
* Update HDCP to use the DMUB for locality check if supported.
* Add DC_HDCP_LC_FORCE_FW_ENABLE and DC_HDCP_LC_ENABLE_SW_FALLBACK.
* Make the first enable new flow regardless of resource capabilities.
* Make the second enable fallback to old SW flow.
* Clean up makefile source file listings for easier updates.

Reviewed-by: Alvin Lee <alvin.lee2@amd.com>
Signed-off-by: Dominik Kaszewski <dominik.kaszewski@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 138 insertions, 10 deletions

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index f1de629c7637..40915767265d 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -115,6 +115,8 @@
 #include "modules/inc/mod_freesync.h"
 #include "modules/power/power_helpers.h"
 
+static_assert(AMDGPU_DMUB_NOTIFICATION_MAX == DMUB_NOTIFICATION_MAX, "AMDGPU_DMUB_NOTIFICATION_MAX mismatch");
+
 #define FIRMWARE_RENOIR_DMUB "amdgpu/renoir_dmcub.bin"
 MODULE_FIRMWARE(FIRMWARE_RENOIR_DMUB);
 #define FIRMWARE_SIENNA_CICHLID_DMUB "amdgpu/sienna_cichlid_dmcub.bin"
@@ -749,6 +751,29 @@ static void dmub_aux_setconfig_callback(struct amdgpu_device *adev,
 		complete(&adev->dm.dmub_aux_transfer_done);
 }
 
+static void dmub_aux_fused_io_callback(struct amdgpu_device *adev,
+					struct dmub_notification *notify)
+{
+	if (!adev || !notify) {
+		ASSERT(false);
+		return;
+	}
+
+	const struct dmub_cmd_fused_request *req = &notify->fused_request;
+	const uint8_t ddc_line = req->u.aux.ddc_line;
+
+	if (ddc_line >= ARRAY_SIZE(adev->dm.fused_io)) {
+		ASSERT(false);
+		return;
+	}
+
+	struct fused_io_sync *sync = &adev->dm.fused_io[ddc_line];
+
+	static_assert(sizeof(*req) <= sizeof(sync->reply_data), "Size mismatch");
+	memcpy(sync->reply_data, req, sizeof(*req));
+	complete(&sync->replied);
+}
+
 /**
  * dmub_hpd_callback - DMUB HPD interrupt processing callback.
  * @adev: amdgpu_device pointer
@@ -885,6 +910,30 @@ static void dm_handle_hpd_work(struct work_struct *work)
 
 }
 
+static const char *dmub_notification_type_str(enum dmub_notification_type e)
+{
+	switch (e) {
+	case DMUB_NOTIFICATION_NO_DATA:
+		return "NO_DATA";
+	case DMUB_NOTIFICATION_AUX_REPLY:
+		return "AUX_REPLY";
+	case DMUB_NOTIFICATION_HPD:
+		return "HPD";
+	case DMUB_NOTIFICATION_HPD_IRQ:
+		return "HPD_IRQ";
+	case DMUB_NOTIFICATION_SET_CONFIG_REPLY:
+		return "SET_CONFIG_REPLY";
+	case DMUB_NOTIFICATION_DPIA_NOTIFICATION:
+		return "DPIA_NOTIFICATION";
+	case DMUB_NOTIFICATION_HPD_SENSE_NOTIFY:
+		return "HPD_SENSE_NOTIFY";
+	case DMUB_NOTIFICATION_FUSED_IO:
+		return "FUSED_IO";
+	default:
+		return "<unknown>";
+	}
+}
+
 #define DMUB_TRACE_MAX_READ 64
 /**
  * dm_dmub_outbox1_low_irq() - Handles Outbox interrupt
@@ -902,15 +951,6 @@ static void dm_dmub_outbox1_low_irq(void *interrupt_params)
 	struct dmcub_trace_buf_entry entry = { 0 };
 	u32 count = 0;
 	struct dmub_hpd_work *dmub_hpd_wrk;
-	static const char *const event_type[] = {
-		"NO_DATA",
-		"AUX_REPLY",
-		"HPD",
-		"HPD_IRQ",
-		"SET_CONFIGC_REPLY",
-		"DPIA_NOTIFICATION",
-		"HPD_SENSE_NOTIFY",
-	};
 
 	do {
 		if (dc_dmub_srv_get_dmub_outbox0_msg(dm->dc, &entry)) {
@@ -940,7 +980,7 @@ static void dm_dmub_outbox1_low_irq(void *interrupt_params)
 			}
 			if (!dm->dmub_callback[notify.type]) {
 				drm_warn(adev_to_drm(adev), "DMUB notification skipped due to no handler: type=%s\n",
-					event_type[notify.type]);
+					dmub_notification_type_str(notify.type));
 				continue;
 			}
 			if (dm->dmub_thread_offload[notify.type] == true) {
@@ -2131,6 +2171,12 @@ static int amdgpu_dm_init(struct amdgpu_device *adev)
 		adev->dm.dc->debug.using_dml21 = true;
 	}
 
+	if (amdgpu_dc_debug_mask & DC_HDCP_LC_FORCE_FW_ENABLE)
+		adev->dm.dc->debug.hdcp_lc_force_fw_enable = true;
+
+	if (amdgpu_dc_debug_mask & DC_HDCP_LC_ENABLE_SW_FALLBACK)
+		adev->dm.dc->debug.hdcp_lc_enable_sw_fallback = true;
+
 	adev->dm.dc->debug.visual_confirm = amdgpu_dc_visual_confirm;
 
 	/* TODO: Remove after DP2 receiver gets proper support of Cable ID feature */
@@ -2213,6 +2259,15 @@ static int amdgpu_dm_init(struct amdgpu_device *adev)
 			drm_err(adev_to_drm(adev), "amdgpu: fail to register dmub aux callback");
 			goto error;
 		}
+
+		for (size_t i = 0; i < ARRAY_SIZE(adev->dm.fused_io); i++)
+			init_completion(&adev->dm.fused_io[i].replied);
+
+		if (!register_dmub_notify_callback(adev, DMUB_NOTIFICATION_FUSED_IO,
+			dmub_aux_fused_io_callback, false)) {
+			drm_err(adev_to_drm(adev), "amdgpu: fail to register dmub fused io callback");
+			goto error;
+		}
 		/* Enable outbox notification only after IRQ handlers are registered and DMUB is alive.
 		 * It is expected that DMUB will resend any pending notifications at this point. Note
 		 * that hpd and hpd_irq handler registration are deferred to register_hpd_handlers() to
@@ -12812,6 +12867,79 @@ out:
 	return ret;
 }
 
+static void abort_fused_io(
+		struct dc_context *ctx,
+		const struct dmub_cmd_fused_request *request
+)
+{
+	union dmub_rb_cmd command = { 0 };
+	struct dmub_rb_cmd_fused_io *io = &command.fused_io;
+
+	io->header.type = DMUB_CMD__FUSED_IO;
+	io->header.sub_type = DMUB_CMD__FUSED_IO_ABORT;
+	io->header.payload_bytes = sizeof(*io) - sizeof(io->header);
+	io->request = *request;
+	dm_execute_dmub_cmd(ctx, &command, DM_DMUB_WAIT_TYPE_NO_WAIT);
+}
+
+static bool execute_fused_io(
+		struct amdgpu_device *dev,
+		struct dc_context *ctx,
+		union dmub_rb_cmd *commands,
+		uint8_t count,
+		uint32_t timeout_us
+)
+{
+	const uint8_t ddc_line = commands[0].fused_io.request.u.aux.ddc_line;
+
+	if (ddc_line >= ARRAY_SIZE(dev->dm.fused_io))
+		return false;
+
+	struct fused_io_sync *sync = &dev->dm.fused_io[ddc_line];
+	struct dmub_rb_cmd_fused_io *first = &commands[0].fused_io;
+	const bool result = dm_execute_dmub_cmd_list(ctx, count, commands, DM_DMUB_WAIT_TYPE_WAIT_WITH_REPLY)
+			&& first->header.ret_status
+			&& first->request.status == FUSED_REQUEST_STATUS_SUCCESS;
+
+	if (!result)
+		return false;
+
+	while (wait_for_completion_timeout(&sync->replied, usecs_to_jiffies(timeout_us))) {
+		reinit_completion(&sync->replied);
+
+		struct dmub_cmd_fused_request *reply = (struct dmub_cmd_fused_request *) sync->reply_data;
+
+		static_assert(sizeof(*reply) <= sizeof(sync->reply_data), "Size mismatch");
+
+		if (reply->identifier == first->request.identifier) {
+			first->request = *reply;
+			return true;
+		}
+	}
+
+	reinit_completion(&sync->replied);
+	first->request.status = FUSED_REQUEST_STATUS_TIMEOUT;
+	abort_fused_io(ctx, &first->request);
+	return false;
+}
+
+bool amdgpu_dm_execute_fused_io(
+		struct amdgpu_device *dev,
+		struct dc_link *link,
+		union dmub_rb_cmd *commands,
+		uint8_t count,
+		uint32_t timeout_us)
+{
+	struct amdgpu_display_manager *dm = &dev->dm;
+
+	mutex_lock(&dm->dpia_aux_lock);
+
+	const bool result = execute_fused_io(dev, link->ctx, commands, count, timeout_us);
+
+	mutex_unlock(&dm->dpia_aux_lock);
+	return result;
+}
+
 int amdgpu_dm_process_dmub_set_config_sync(
 		struct dc_context *ctx,
 		unsigned int link_index,