2 * Copyright (C) 2016 Broadcom Limited
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 as published by
6 * the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * You should have received a copy of the GNU General Public License along with
14 * this program. If not, see <http://www.gnu.org/licenses/>.
20 * The VC4 DPI hardware supports MIPI DPI type 4 and Nokia ViSSI
21 * signals. On BCM2835, these can be routed out to GPIO0-27 with the
25 #include <drm/drm_atomic_helper.h>
26 #include <drm/drm_bridge.h>
27 #include <drm/drm_crtc_helper.h>
28 #include <drm/drm_edid.h>
29 #include <drm/drm_of.h>
30 #include <drm/drm_panel.h>
31 #include <linux/clk.h>
32 #include <linux/component.h>
33 #include <linux/of_graph.h>
34 #include <linux/of_platform.h>
39 # define DPI_OUTPUT_ENABLE_MODE BIT(16)
41 /* The order field takes the incoming 24 bit RGB from the pixel valve
42 * and shuffles the 3 channels.
44 # define DPI_ORDER_MASK VC4_MASK(15, 14)
45 # define DPI_ORDER_SHIFT 14
46 # define DPI_ORDER_RGB 0
47 # define DPI_ORDER_BGR 1
48 # define DPI_ORDER_GRB 2
49 # define DPI_ORDER_BRG 3
51 /* The format field takes the ORDER-shuffled pixel valve data and
52 * formats it onto the output lines.
54 # define DPI_FORMAT_MASK VC4_MASK(13, 11)
55 # define DPI_FORMAT_SHIFT 11
56 /* This define is named in the hardware, but actually just outputs 0. */
57 # define DPI_FORMAT_9BIT_666_RGB 0
58 /* Outputs 00000000rrrrrggggggbbbbb */
59 # define DPI_FORMAT_16BIT_565_RGB_1 1
60 /* Outputs 000rrrrr00gggggg000bbbbb */
61 # define DPI_FORMAT_16BIT_565_RGB_2 2
62 /* Outputs 00rrrrr000gggggg00bbbbb0 */
63 # define DPI_FORMAT_16BIT_565_RGB_3 3
64 /* Outputs 000000rrrrrrggggggbbbbbb */
65 # define DPI_FORMAT_18BIT_666_RGB_1 4
66 /* Outputs 00rrrrrr00gggggg00bbbbbb */
67 # define DPI_FORMAT_18BIT_666_RGB_2 5
68 /* Outputs rrrrrrrrggggggggbbbbbbbb */
69 # define DPI_FORMAT_24BIT_888_RGB 6
71 /* Reverses the polarity of the corresponding signal */
72 # define DPI_PIXEL_CLK_INVERT BIT(10)
73 # define DPI_HSYNC_INVERT BIT(9)
74 # define DPI_VSYNC_INVERT BIT(8)
75 # define DPI_OUTPUT_ENABLE_INVERT BIT(7)
77 /* Outputs the signal the falling clock edge instead of rising. */
78 # define DPI_HSYNC_NEGATE BIT(6)
79 # define DPI_VSYNC_NEGATE BIT(5)
80 # define DPI_OUTPUT_ENABLE_NEGATE BIT(4)
82 /* Disables the signal */
83 # define DPI_HSYNC_DISABLE BIT(3)
84 # define DPI_VSYNC_DISABLE BIT(2)
85 # define DPI_OUTPUT_ENABLE_DISABLE BIT(1)
87 /* Power gate to the device, full reset at 0 -> 1 transition */
88 # define DPI_ENABLE BIT(0)
90 /* All other registers besides DPI_C return the ID */
92 # define DPI_ID_VALUE 0x00647069
94 /* General DPI hardware state. */
96 struct platform_device *pdev;
98 struct drm_encoder *encoder;
102 struct clk *pixel_clock;
103 struct clk *core_clock;
106 #define DPI_READ(offset) readl(dpi->regs + (offset))
107 #define DPI_WRITE(offset, val) writel(val, dpi->regs + (offset))
109 /* VC4 DPI encoder KMS struct */
110 struct vc4_dpi_encoder {
111 struct vc4_encoder base;
115 static inline struct vc4_dpi_encoder *
116 to_vc4_dpi_encoder(struct drm_encoder *encoder)
118 return container_of(encoder, struct vc4_dpi_encoder, base.base);
121 #define DPI_REG(reg) { reg, #reg }
122 static const struct {
130 #ifdef CONFIG_DEBUG_FS
131 int vc4_dpi_debugfs_regs(struct seq_file *m, void *unused)
133 struct drm_info_node *node = (struct drm_info_node *)m->private;
134 struct drm_device *dev = node->minor->dev;
135 struct vc4_dev *vc4 = to_vc4_dev(dev);
136 struct vc4_dpi *dpi = vc4->dpi;
142 for (i = 0; i < ARRAY_SIZE(dpi_regs); i++) {
143 seq_printf(m, "%s (0x%04x): 0x%08x\n",
144 dpi_regs[i].name, dpi_regs[i].reg,
145 DPI_READ(dpi_regs[i].reg));
152 static const struct drm_encoder_funcs vc4_dpi_encoder_funcs = {
153 .destroy = drm_encoder_cleanup,
156 static void vc4_dpi_encoder_disable(struct drm_encoder *encoder)
158 struct vc4_dpi_encoder *vc4_encoder = to_vc4_dpi_encoder(encoder);
159 struct vc4_dpi *dpi = vc4_encoder->dpi;
161 clk_disable_unprepare(dpi->pixel_clock);
164 static void vc4_dpi_encoder_enable(struct drm_encoder *encoder)
166 struct drm_device *dev = encoder->dev;
167 struct drm_display_mode *mode = &encoder->crtc->mode;
168 struct vc4_dpi_encoder *vc4_encoder = to_vc4_dpi_encoder(encoder);
169 struct vc4_dpi *dpi = vc4_encoder->dpi;
170 struct drm_connector_list_iter conn_iter;
171 struct drm_connector *connector = NULL, *connector_scan;
172 u32 dpi_c = DPI_ENABLE | DPI_OUTPUT_ENABLE_MODE;
175 /* Look up the connector attached to DPI so we can get the
176 * bus_format. Ideally the bridge would tell us the
177 * bus_format we want, but it doesn't yet, so assume that it's
178 * uniform throughout the bridge chain.
180 drm_connector_list_iter_begin(dev, &conn_iter);
181 drm_for_each_connector_iter(connector_scan, &conn_iter) {
182 if (connector_scan->encoder == encoder) {
183 connector = connector_scan;
187 drm_connector_list_iter_end(&conn_iter);
190 if (connector->display_info.num_bus_formats) {
191 u32 bus_format = connector->display_info.bus_formats[0];
193 switch (bus_format) {
194 case MEDIA_BUS_FMT_RGB888_1X24:
195 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_24BIT_888_RGB,
198 case MEDIA_BUS_FMT_BGR888_1X24:
199 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_24BIT_888_RGB,
201 dpi_c |= VC4_SET_FIELD(DPI_ORDER_BGR,
204 case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
205 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_18BIT_666_RGB_2,
208 case MEDIA_BUS_FMT_RGB666_1X18:
209 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_18BIT_666_RGB_1,
212 case MEDIA_BUS_FMT_RGB565_1X16:
213 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_16BIT_565_RGB_1,
217 DRM_ERROR("Unknown media bus format %d\n",
223 if (connector->display_info.bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE)
224 dpi_c |= DPI_PIXEL_CLK_INVERT;
226 if (connector->display_info.bus_flags & DRM_BUS_FLAG_DE_LOW)
227 dpi_c |= DPI_OUTPUT_ENABLE_INVERT;
229 /* Default to 24bit if no connector found. */
230 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_24BIT_888_RGB, DPI_FORMAT);
233 if (mode->flags & DRM_MODE_FLAG_NHSYNC)
234 dpi_c |= DPI_HSYNC_INVERT;
235 else if (!(mode->flags & DRM_MODE_FLAG_PHSYNC))
236 dpi_c |= DPI_HSYNC_DISABLE;
238 if (mode->flags & DRM_MODE_FLAG_NVSYNC)
239 dpi_c |= DPI_VSYNC_INVERT;
240 else if (!(mode->flags & DRM_MODE_FLAG_PVSYNC))
241 dpi_c |= DPI_VSYNC_DISABLE;
243 DPI_WRITE(DPI_C, dpi_c);
245 ret = clk_set_rate(dpi->pixel_clock, mode->clock * 1000);
247 DRM_ERROR("Failed to set clock rate: %d\n", ret);
249 ret = clk_prepare_enable(dpi->pixel_clock);
251 DRM_ERROR("Failed to set clock rate: %d\n", ret);
254 static enum drm_mode_status vc4_dpi_encoder_mode_valid(struct drm_encoder *encoder,
255 const struct drm_display_mode *mode)
257 if (mode->flags & DRM_MODE_FLAG_INTERLACE)
258 return MODE_NO_INTERLACE;
263 static const struct drm_encoder_helper_funcs vc4_dpi_encoder_helper_funcs = {
264 .disable = vc4_dpi_encoder_disable,
265 .enable = vc4_dpi_encoder_enable,
266 .mode_valid = vc4_dpi_encoder_mode_valid,
269 static const struct of_device_id vc4_dpi_dt_match[] = {
270 { .compatible = "brcm,bcm2835-dpi", .data = NULL },
274 /* Sets up the next link in the display chain, whether it's a panel or
277 static int vc4_dpi_init_bridge(struct vc4_dpi *dpi)
279 struct device *dev = &dpi->pdev->dev;
280 struct drm_panel *panel;
281 struct drm_bridge *bridge;
284 ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0,
287 /* If nothing was connected in the DT, that's not an
297 bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_DPI);
299 return drm_bridge_attach(dpi->encoder, bridge, NULL);
302 static int vc4_dpi_bind(struct device *dev, struct device *master, void *data)
304 struct platform_device *pdev = to_platform_device(dev);
305 struct drm_device *drm = dev_get_drvdata(master);
306 struct vc4_dev *vc4 = to_vc4_dev(drm);
308 struct vc4_dpi_encoder *vc4_dpi_encoder;
311 dpi = devm_kzalloc(dev, sizeof(*dpi), GFP_KERNEL);
315 vc4_dpi_encoder = devm_kzalloc(dev, sizeof(*vc4_dpi_encoder),
317 if (!vc4_dpi_encoder)
319 vc4_dpi_encoder->base.type = VC4_ENCODER_TYPE_DPI;
320 vc4_dpi_encoder->dpi = dpi;
321 dpi->encoder = &vc4_dpi_encoder->base.base;
324 dpi->regs = vc4_ioremap_regs(pdev, 0);
325 if (IS_ERR(dpi->regs))
326 return PTR_ERR(dpi->regs);
328 if (DPI_READ(DPI_ID) != DPI_ID_VALUE) {
329 dev_err(dev, "Port returned 0x%08x for ID instead of 0x%08x\n",
330 DPI_READ(DPI_ID), DPI_ID_VALUE);
334 dpi->core_clock = devm_clk_get(dev, "core");
335 if (IS_ERR(dpi->core_clock)) {
336 ret = PTR_ERR(dpi->core_clock);
337 if (ret != -EPROBE_DEFER)
338 DRM_ERROR("Failed to get core clock: %d\n", ret);
341 dpi->pixel_clock = devm_clk_get(dev, "pixel");
342 if (IS_ERR(dpi->pixel_clock)) {
343 ret = PTR_ERR(dpi->pixel_clock);
344 if (ret != -EPROBE_DEFER)
345 DRM_ERROR("Failed to get pixel clock: %d\n", ret);
349 ret = clk_prepare_enable(dpi->core_clock);
351 DRM_ERROR("Failed to turn on core clock: %d\n", ret);
353 drm_encoder_init(drm, dpi->encoder, &vc4_dpi_encoder_funcs,
354 DRM_MODE_ENCODER_DPI, NULL);
355 drm_encoder_helper_add(dpi->encoder, &vc4_dpi_encoder_helper_funcs);
357 ret = vc4_dpi_init_bridge(dpi);
359 goto err_destroy_encoder;
361 dev_set_drvdata(dev, dpi);
368 drm_encoder_cleanup(dpi->encoder);
369 clk_disable_unprepare(dpi->core_clock);
373 static void vc4_dpi_unbind(struct device *dev, struct device *master,
376 struct drm_device *drm = dev_get_drvdata(master);
377 struct vc4_dev *vc4 = to_vc4_dev(drm);
378 struct vc4_dpi *dpi = dev_get_drvdata(dev);
380 drm_of_panel_bridge_remove(dev->of_node, 0, 0);
382 drm_encoder_cleanup(dpi->encoder);
384 clk_disable_unprepare(dpi->core_clock);
389 static const struct component_ops vc4_dpi_ops = {
390 .bind = vc4_dpi_bind,
391 .unbind = vc4_dpi_unbind,
394 static int vc4_dpi_dev_probe(struct platform_device *pdev)
396 return component_add(&pdev->dev, &vc4_dpi_ops);
399 static int vc4_dpi_dev_remove(struct platform_device *pdev)
401 component_del(&pdev->dev, &vc4_dpi_ops);
405 struct platform_driver vc4_dpi_driver = {
406 .probe = vc4_dpi_dev_probe,
407 .remove = vc4_dpi_dev_remove,
410 .of_match_table = vc4_dpi_dt_match,