drm/amd/display: Initialize writeback connector

[WHAT]
Create a drm_writeback_connector when connector signal equals
SIGNAL_TYPE_VIRTUAL.
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/Makefile

@@ -37,7 +37,8 @@ AMDGPUDM = \
 	amdgpu_dm_helpers.o \
 	amdgpu_dm_pp_smu.o \
 	amdgpu_dm_psr.o \
-	amdgpu_dm_replay.o
+	amdgpu_dm_replay.o \
+	amdgpu_dm_wb.o
 
 ifdef CONFIG_DRM_AMD_DC_FP
 AMDGPUDM += dc_fpu.o

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -54,6 +54,7 @@
 #include "amdgpu_dm_crtc.h"
 #include "amdgpu_dm_hdcp.h"
 #include <drm/display/drm_hdcp_helper.h>
+#include "amdgpu_dm_wb.h"
 #include "amdgpu_pm.h"
 #include "amdgpu_atombios.h"
 
@@ -4511,8 +4512,25 @@ static int amdgpu_dm_initialize_drm_device(struct amdgpu_device *adev)
 
 		link = dc_get_link_at_index(dm->dc, i);
 
-		if (link->connector_signal == SIGNAL_TYPE_VIRTUAL)
+		if (link->connector_signal == SIGNAL_TYPE_VIRTUAL) {
+			struct drm_writeback_connector *wbcon = kzalloc(sizeof(*wbcon), GFP_KERNEL);
+
+			if (!wbcon) {
+				DRM_ERROR("KMS: Failed to allocate writeback connector\n");
+				continue;
+			}
+
+			if (amdgpu_dm_wb_connector_init(dm, wbcon)) {
+				DRM_ERROR("KMS: Failed to initialize writeback connector\n");
+				kfree(wbcon);
+				continue;
+			}
+
+			link->psr_settings.psr_feature_enabled = false;
+			link->psr_settings.psr_version = DC_PSR_VERSION_UNSUPPORTED;
+
 			continue;
+		}
 
 		aconnector = kzalloc(sizeof(*aconnector), GFP_KERNEL);
 		if (!aconnector)

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_wb.c

+// SPDX-License-Identifier: MIT
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#include "dm_services_types.h"
+
+#include "amdgpu.h"
+#include "amdgpu_dm.h"
+#include "amdgpu_dm_wb.h"
+#include "amdgpu_display.h"
+
+#include <drm/drm_atomic_state_helper.h>
+#include <drm/drm_modeset_helper_vtables.h>
+
+static const u32 amdgpu_dm_wb_formats[] = {
+	DRM_FORMAT_XRGB2101010,
+};
+
+static int amdgpu_dm_wb_encoder_atomic_check(struct drm_encoder *encoder,
+					struct drm_crtc_state *crtc_state,
+					struct drm_connector_state *conn_state)
+{
+	struct drm_framebuffer *fb;
+	const struct drm_display_mode *mode = &crtc_state->mode;
+	bool found = false;
+	uint8_t i;
+
+	if (!conn_state->writeback_job || !conn_state->writeback_job->fb)
+		return 0;
+
+	fb = conn_state->writeback_job->fb;
+	if (fb->width != mode->hdisplay || fb->height != mode->vdisplay) {
+		DRM_DEBUG_KMS("Invalid framebuffer size %ux%u\n",
+			      fb->width, fb->height);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < sizeof(amdgpu_dm_wb_formats) / sizeof(u32); i++) {
+		if (fb->format->format == amdgpu_dm_wb_formats[i])
+			found = true;
+	}
+
+	if (!found) {
+		DRM_DEBUG_KMS("Invalid pixel format %p4cc\n",
+			      &fb->format->format);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+
+static int amdgpu_dm_wb_connector_get_modes(struct drm_connector *connector)
+{
+	struct drm_device *dev = connector->dev;
+
+	return drm_add_modes_noedid(connector, dev->mode_config.max_width,
+				    dev->mode_config.max_height);
+}
+
+static int amdgpu_dm_wb_prepare_job(struct drm_writeback_connector *wb_connector,
+			       struct drm_writeback_job *job)
+{
+	struct amdgpu_framebuffer *afb;
+	struct drm_gem_object *obj;
+	struct amdgpu_device *adev;
+	struct amdgpu_bo *rbo;
+	uint32_t domain;
+	int r;
+
+	if (!job->fb) {
+		DRM_DEBUG_KMS("No FB bound\n");
+		return 0;
+	}
+
+	afb = to_amdgpu_framebuffer(job->fb);
+	obj = job->fb->obj[0];
+	rbo = gem_to_amdgpu_bo(obj);
+	adev = amdgpu_ttm_adev(rbo->tbo.bdev);
+
+	r = amdgpu_bo_reserve(rbo, true);
+	if (r) {
+		dev_err(adev->dev, "fail to reserve bo (%d)\n", r);
+		return r;
+	}
+
+	r = dma_resv_reserve_fences(rbo->tbo.base.resv, 1);
+	if (r) {
+		dev_err(adev->dev, "reserving fence slot failed (%d)\n", r);
+		goto error_unlock;
+	}
+
+	domain = amdgpu_display_supported_domains(adev, rbo->flags);
+
+	r = amdgpu_bo_pin(rbo, domain);
+	if (unlikely(r != 0)) {
+		if (r != -ERESTARTSYS)
+			DRM_ERROR("Failed to pin framebuffer with error %d\n", r);
+		goto error_unlock;
+	}
+
+	r = amdgpu_ttm_alloc_gart(&rbo->tbo);
+	if (unlikely(r != 0)) {
+		DRM_ERROR("%p bind failed\n", rbo);
+		goto error_unpin;
+	}
+
+	amdgpu_bo_unreserve(rbo);
+
+	afb->address = amdgpu_bo_gpu_offset(rbo);
+
+	amdgpu_bo_ref(rbo);
+
+	return 0;
+
+error_unpin:
+	amdgpu_bo_unpin(rbo);
+
+error_unlock:
+	amdgpu_bo_unreserve(rbo);
+	return r;
+}
+
+static void amdgpu_dm_wb_cleanup_job(struct drm_writeback_connector *connector,
+				struct drm_writeback_job *job)
+{
+	struct amdgpu_bo *rbo;
+	int r;
+
+	if (!job->fb)
+		return;
+
+	rbo = gem_to_amdgpu_bo(job->fb->obj[0]);
+	r = amdgpu_bo_reserve(rbo, false);
+	if (unlikely(r)) {
+		DRM_ERROR("failed to reserve rbo before unpin\n");
+		return;
+	}
+
+	amdgpu_bo_unpin(rbo);
+	amdgpu_bo_unreserve(rbo);
+	amdgpu_bo_unref(&rbo);
+}
+
+static const struct drm_encoder_helper_funcs amdgpu_dm_wb_encoder_helper_funcs = {
+	.atomic_check = amdgpu_dm_wb_encoder_atomic_check,
+};
+
+static const struct drm_connector_funcs amdgpu_dm_wb_connector_funcs = {
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.destroy = drm_connector_cleanup,
+	.reset = amdgpu_dm_connector_funcs_reset,
+	.atomic_duplicate_state = amdgpu_dm_connector_atomic_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static const struct drm_connector_helper_funcs amdgpu_dm_wb_conn_helper_funcs = {
+	.get_modes = amdgpu_dm_wb_connector_get_modes,
+	.prepare_writeback_job = amdgpu_dm_wb_prepare_job,
+	.cleanup_writeback_job = amdgpu_dm_wb_cleanup_job,
+};
+
+int amdgpu_dm_wb_connector_init(struct amdgpu_display_manager *dm,
+				struct drm_writeback_connector *wbcon)
+{
+	int res = 0;
+
+	drm_connector_helper_add(&wbcon->base, &amdgpu_dm_wb_conn_helper_funcs);
+
+	res = drm_writeback_connector_init(&dm->adev->ddev, wbcon,
+					    &amdgpu_dm_wb_connector_funcs,
+					    &amdgpu_dm_wb_encoder_helper_funcs,
+					    amdgpu_dm_wb_formats,
+					    ARRAY_SIZE(amdgpu_dm_wb_formats),
+					    amdgpu_dm_get_encoder_crtc_mask(dm->adev));
+
+	if (res)
+		return res;
+	/*
+	 * Some of the properties below require access to state, like bpc.
+	 * Allocate some default initial connector state with our reset helper.
+	 */
+	if (wbcon->base.funcs->reset)
+		wbcon->base.funcs->reset(&wbcon->base);
+
+	return 0;
+}

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_wb.h

+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef __AMDGPU_DM_WB_H__
+#define __AMDGPU_DM_WB_H__
+
+#include <drm/drm_writeback.h>
+
+int amdgpu_dm_wb_connector_init(struct amdgpu_display_manager *dm,
+				struct drm_writeback_connector *wbcon);
+
+#endif