1// SPDX-License-Identifier: GPL-2.0
2/*
3 * rcar_du_writeback.c  --  R-Car Display Unit Writeback Support
4 *
5 * Copyright (C) 2019 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
6 */
7
8#include <drm/drm_atomic_helper.h>
9#include <drm/drm_device.h>
10#include <drm/drm_fourcc.h>
11#include <drm/drm_probe_helper.h>
12#include <drm/drm_writeback.h>
13
14#include "rcar_du_crtc.h"
15#include "rcar_du_drv.h"
16#include "rcar_du_kms.h"
17#include "rcar_du_writeback.h"
18
19/**
20 * struct rcar_du_wb_conn_state - Driver-specific writeback connector state
21 * @state: base DRM connector state
22 * @format: format of the writeback framebuffer
23 */
24struct rcar_du_wb_conn_state {
25	struct drm_connector_state state;
26	const struct rcar_du_format_info *format;
27};
28
29#define to_rcar_wb_conn_state(s) \
30	container_of(s, struct rcar_du_wb_conn_state, state)
31
32/**
33 * struct rcar_du_wb_job - Driver-private data for writeback jobs
34 * @sg_tables: scatter-gather tables for the framebuffer memory
35 */
36struct rcar_du_wb_job {
37	struct sg_table sg_tables[3];
38};
39
40static int rcar_du_wb_conn_get_modes(struct drm_connector *connector)
41{
42	struct drm_device *dev = connector->dev;
43
44	return drm_add_modes_noedid(connector, dev->mode_config.max_width,
45				    dev->mode_config.max_height);
46}
47
48static int rcar_du_wb_prepare_job(struct drm_writeback_connector *connector,
49				  struct drm_writeback_job *job)
50{
51	struct rcar_du_crtc *rcrtc = wb_to_rcar_crtc(connector);
52	struct rcar_du_wb_job *rjob;
53	int ret;
54
55	if (!job->fb)
56		return 0;
57
58	rjob = kzalloc(sizeof(*rjob), GFP_KERNEL);
59	if (!rjob)
60		return -ENOMEM;
61
62	/* Map the framebuffer to the VSP. */
63	ret = rcar_du_vsp_map_fb(rcrtc->vsp, job->fb, rjob->sg_tables);
64	if (ret < 0) {
65		kfree(rjob);
66		return ret;
67	}
68
69	job->priv = rjob;
70	return 0;
71}
72
73static void rcar_du_wb_cleanup_job(struct drm_writeback_connector *connector,
74				   struct drm_writeback_job *job)
75{
76	struct rcar_du_crtc *rcrtc = wb_to_rcar_crtc(connector);
77	struct rcar_du_wb_job *rjob = job->priv;
78
79	if (!job->fb)
80		return;
81
82	rcar_du_vsp_unmap_fb(rcrtc->vsp, job->fb, rjob->sg_tables);
83	kfree(rjob);
84}
85
86static const struct drm_connector_helper_funcs rcar_du_wb_conn_helper_funcs = {
87	.get_modes = rcar_du_wb_conn_get_modes,
88	.prepare_writeback_job = rcar_du_wb_prepare_job,
89	.cleanup_writeback_job = rcar_du_wb_cleanup_job,
90};
91
92static struct drm_connector_state *
93rcar_du_wb_conn_duplicate_state(struct drm_connector *connector)
94{
95	struct rcar_du_wb_conn_state *copy;
96
97	if (WARN_ON(!connector->state))
98		return NULL;
99
100	copy = kzalloc(sizeof(*copy), GFP_KERNEL);
101	if (!copy)
102		return NULL;
103
104	__drm_atomic_helper_connector_duplicate_state(connector, &copy->state);
105
106	return &copy->state;
107}
108
109static void rcar_du_wb_conn_destroy_state(struct drm_connector *connector,
110					  struct drm_connector_state *state)
111{
112	__drm_atomic_helper_connector_destroy_state(state);
113	kfree(to_rcar_wb_conn_state(state));
114}
115
116static void rcar_du_wb_conn_reset(struct drm_connector *connector)
117{
118	struct rcar_du_wb_conn_state *state;
119
120	if (connector->state) {
121		rcar_du_wb_conn_destroy_state(connector, connector->state);
122		connector->state = NULL;
123	}
124
125	state = kzalloc(sizeof(*state), GFP_KERNEL);
126	if (state == NULL)
127		return;
128
129	__drm_atomic_helper_connector_reset(connector, &state->state);
130}
131
132static const struct drm_connector_funcs rcar_du_wb_conn_funcs = {
133	.reset = rcar_du_wb_conn_reset,
134	.fill_modes = drm_helper_probe_single_connector_modes,
135	.destroy = drm_connector_cleanup,
136	.atomic_duplicate_state = rcar_du_wb_conn_duplicate_state,
137	.atomic_destroy_state = rcar_du_wb_conn_destroy_state,
138};
139
140static int rcar_du_wb_enc_atomic_check(struct drm_encoder *encoder,
141				       struct drm_crtc_state *crtc_state,
142				       struct drm_connector_state *conn_state)
143{
144	struct rcar_du_wb_conn_state *wb_state =
145		to_rcar_wb_conn_state(conn_state);
146	const struct drm_display_mode *mode = &crtc_state->mode;
147	struct drm_device *dev = encoder->dev;
148	struct drm_framebuffer *fb;
149
150	if (!conn_state->writeback_job)
151		return 0;
152
153	fb = conn_state->writeback_job->fb;
154
155	/*
156	 * Verify that the framebuffer format is supported and that its size
157	 * matches the current mode.
158	 */
159	if (fb->width != mode->hdisplay || fb->height != mode->vdisplay) {
160		dev_dbg(dev->dev, "%s: invalid framebuffer size %ux%u\n",
161			__func__, fb->width, fb->height);
162		return -EINVAL;
163	}
164
165	wb_state->format = rcar_du_format_info(fb->format->format);
166	if (wb_state->format == NULL) {
167		dev_dbg(dev->dev, "%s: unsupported format %08x\n", __func__,
168			fb->format->format);
169		return -EINVAL;
170	}
171
172	return 0;
173}
174
175static const struct drm_encoder_helper_funcs rcar_du_wb_enc_helper_funcs = {
176	.atomic_check = rcar_du_wb_enc_atomic_check,
177};
178
179/*
180 * Only RGB formats are currently supported as the VSP outputs RGB to the DU
181 * and can't convert to YUV separately for writeback.
182 */
183static const u32 writeback_formats[] = {
184	DRM_FORMAT_RGB332,
185	DRM_FORMAT_ARGB4444,
186	DRM_FORMAT_XRGB4444,
187	DRM_FORMAT_ARGB1555,
188	DRM_FORMAT_XRGB1555,
189	DRM_FORMAT_RGB565,
190	DRM_FORMAT_BGR888,
191	DRM_FORMAT_RGB888,
192	DRM_FORMAT_BGRA8888,
193	DRM_FORMAT_BGRX8888,
194	DRM_FORMAT_ARGB8888,
195	DRM_FORMAT_XRGB8888,
196};
197
198int rcar_du_writeback_init(struct rcar_du_device *rcdu,
199			   struct rcar_du_crtc *rcrtc)
200{
201	struct drm_writeback_connector *wb_conn = &rcrtc->writeback;
202
203	wb_conn->encoder.possible_crtcs = 1 << drm_crtc_index(&rcrtc->crtc);
204	drm_connector_helper_add(&wb_conn->base,
205				 &rcar_du_wb_conn_helper_funcs);
206
207	return drm_writeback_connector_init(rcdu->ddev, wb_conn,
208					    &rcar_du_wb_conn_funcs,
209					    &rcar_du_wb_enc_helper_funcs,
210					    writeback_formats,
211					    ARRAY_SIZE(writeback_formats));
212}
213
214void rcar_du_writeback_setup(struct rcar_du_crtc *rcrtc,
215			     struct vsp1_du_writeback_config *cfg)
216{
217	struct rcar_du_wb_conn_state *wb_state;
218	struct drm_connector_state *state;
219	struct rcar_du_wb_job *rjob;
220	struct drm_framebuffer *fb;
221	unsigned int i;
222
223	state = rcrtc->writeback.base.state;
224	if (!state || !state->writeback_job)
225		return;
226
227	fb = state->writeback_job->fb;
228	rjob = state->writeback_job->priv;
229	wb_state = to_rcar_wb_conn_state(state);
230
231	cfg->pixelformat = wb_state->format->v4l2;
232	cfg->pitch = fb->pitches[0];
233
234	for (i = 0; i < wb_state->format->planes; ++i)
235		cfg->mem[i] = sg_dma_address(rjob->sg_tables[i].sgl)
236			    + fb->offsets[i];
237
238	drm_writeback_queue_job(&rcrtc->writeback, state);
239}
240
241void rcar_du_writeback_complete(struct rcar_du_crtc *rcrtc)
242{
243	drm_writeback_signal_completion(&rcrtc->writeback, 0);
244}
245