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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2016 Broadcom Limited4 */5 6/**7 * DOC: VC4 DPI module8 *9 * The VC4 DPI hardware supports MIPI DPI type 4 and Nokia ViSSI10 * signals. On BCM2835, these can be routed out to GPIO0-27 with the11 * ALT2 function.12 */13 14#include <drm/drm_atomic_helper.h>15#include <drm/drm_bridge.h>16#include <drm/drm_drv.h>17#include <drm/drm_edid.h>18#include <drm/drm_of.h>19#include <drm/drm_panel.h>20#include <drm/drm_probe_helper.h>21#include <drm/drm_simple_kms_helper.h>22#include <linux/clk.h>23#include <linux/component.h>24#include <linux/media-bus-format.h>25#include <linux/mod_devicetable.h>26#include <linux/platform_device.h>27#include "vc4_drv.h"28#include "vc4_regs.h"29 30#define DPI_C 0x0031# define DPI_OUTPUT_ENABLE_MODE BIT(16)32 33/* The order field takes the incoming 24 bit RGB from the pixel valve34 * and shuffles the 3 channels.35 */36# define DPI_ORDER_MASK VC4_MASK(15, 14)37# define DPI_ORDER_SHIFT 1438# define DPI_ORDER_RGB 039# define DPI_ORDER_BGR 140# define DPI_ORDER_GRB 241# define DPI_ORDER_BRG 342 43/* The format field takes the ORDER-shuffled pixel valve data and44 * formats it onto the output lines.45 */46# define DPI_FORMAT_MASK VC4_MASK(13, 11)47# define DPI_FORMAT_SHIFT 1148/* This define is named in the hardware, but actually just outputs 0. */49# define DPI_FORMAT_9BIT_666_RGB 050/* Outputs 00000000rrrrrggggggbbbbb */51# define DPI_FORMAT_16BIT_565_RGB_1 152/* Outputs 000rrrrr00gggggg000bbbbb */53# define DPI_FORMAT_16BIT_565_RGB_2 254/* Outputs 00rrrrr000gggggg00bbbbb0 */55# define DPI_FORMAT_16BIT_565_RGB_3 356/* Outputs 000000rrrrrrggggggbbbbbb */57# define DPI_FORMAT_18BIT_666_RGB_1 458/* Outputs 00rrrrrr00gggggg00bbbbbb */59# define DPI_FORMAT_18BIT_666_RGB_2 560/* Outputs rrrrrrrrggggggggbbbbbbbb */61# define DPI_FORMAT_24BIT_888_RGB 662 63/* Reverses the polarity of the corresponding signal */64# define DPI_PIXEL_CLK_INVERT BIT(10)65# define DPI_HSYNC_INVERT BIT(9)66# define DPI_VSYNC_INVERT BIT(8)67# define DPI_OUTPUT_ENABLE_INVERT BIT(7)68 69/* Outputs the signal the falling clock edge instead of rising. */70# define DPI_HSYNC_NEGATE BIT(6)71# define DPI_VSYNC_NEGATE BIT(5)72# define DPI_OUTPUT_ENABLE_NEGATE BIT(4)73 74/* Disables the signal */75# define DPI_HSYNC_DISABLE BIT(3)76# define DPI_VSYNC_DISABLE BIT(2)77# define DPI_OUTPUT_ENABLE_DISABLE BIT(1)78 79/* Power gate to the device, full reset at 0 -> 1 transition */80# define DPI_ENABLE BIT(0)81 82/* All other registers besides DPI_C return the ID */83#define DPI_ID 0x0484# define DPI_ID_VALUE 0x0064706985 86/* General DPI hardware state. */87struct vc4_dpi {88 struct vc4_encoder encoder;89 90 struct platform_device *pdev;91 92 void __iomem *regs;93 94 struct clk *pixel_clock;95 struct clk *core_clock;96 97 struct debugfs_regset32 regset;98};99 100#define to_vc4_dpi(_encoder) \101 container_of_const(_encoder, struct vc4_dpi, encoder.base)102 103#define DPI_READ(offset) \104 ({ \105 kunit_fail_current_test("Accessing a register in a unit test!\n"); \106 readl(dpi->regs + (offset)); \107 })108 109#define DPI_WRITE(offset, val) \110 do { \111 kunit_fail_current_test("Accessing a register in a unit test!\n"); \112 writel(val, dpi->regs + (offset)); \113 } while (0)114 115static const struct debugfs_reg32 dpi_regs[] = {116 VC4_REG32(DPI_C),117 VC4_REG32(DPI_ID),118};119 120static void vc4_dpi_encoder_disable(struct drm_encoder *encoder)121{122 struct drm_device *dev = encoder->dev;123 struct vc4_dpi *dpi = to_vc4_dpi(encoder);124 int idx;125 126 if (!drm_dev_enter(dev, &idx))127 return;128 129 clk_disable_unprepare(dpi->pixel_clock);130 131 drm_dev_exit(idx);132}133 134static void vc4_dpi_encoder_enable(struct drm_encoder *encoder)135{136 struct drm_device *dev = encoder->dev;137 struct drm_display_mode *mode = &encoder->crtc->mode;138 struct vc4_dpi *dpi = to_vc4_dpi(encoder);139 struct drm_connector_list_iter conn_iter;140 struct drm_connector *connector = NULL, *connector_scan;141 u32 dpi_c = DPI_ENABLE;142 int idx;143 int ret;144 145 /* Look up the connector attached to DPI so we can get the146 * bus_format. Ideally the bridge would tell us the147 * bus_format we want, but it doesn't yet, so assume that it's148 * uniform throughout the bridge chain.149 */150 drm_connector_list_iter_begin(dev, &conn_iter);151 drm_for_each_connector_iter(connector_scan, &conn_iter) {152 if (connector_scan->encoder == encoder) {153 connector = connector_scan;154 break;155 }156 }157 drm_connector_list_iter_end(&conn_iter);158 159 /* Default to 18bit if no connector or format found. */160 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_18BIT_666_RGB_1, DPI_FORMAT);161 162 if (connector) {163 if (connector->display_info.num_bus_formats) {164 u32 bus_format = connector->display_info.bus_formats[0];165 166 dpi_c &= ~DPI_FORMAT_MASK;167 168 switch (bus_format) {169 case MEDIA_BUS_FMT_RGB888_1X24:170 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_24BIT_888_RGB,171 DPI_FORMAT);172 break;173 case MEDIA_BUS_FMT_BGR888_1X24:174 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_24BIT_888_RGB,175 DPI_FORMAT);176 dpi_c |= VC4_SET_FIELD(DPI_ORDER_BGR,177 DPI_ORDER);178 break;179 case MEDIA_BUS_FMT_BGR666_1X24_CPADHI:180 dpi_c |= VC4_SET_FIELD(DPI_ORDER_BGR, DPI_ORDER);181 fallthrough;182 case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:183 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_18BIT_666_RGB_2,184 DPI_FORMAT);185 break;186 case MEDIA_BUS_FMT_BGR666_1X18:187 dpi_c |= VC4_SET_FIELD(DPI_ORDER_BGR, DPI_ORDER);188 fallthrough;189 case MEDIA_BUS_FMT_RGB666_1X18:190 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_18BIT_666_RGB_1,191 DPI_FORMAT);192 break;193 case MEDIA_BUS_FMT_RGB565_1X16:194 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_16BIT_565_RGB_1,195 DPI_FORMAT);196 break;197 case MEDIA_BUS_FMT_RGB565_1X24_CPADHI:198 dpi_c |= VC4_SET_FIELD(DPI_FORMAT_16BIT_565_RGB_2,199 DPI_FORMAT);200 break;201 default:202 drm_err(dev, "Unknown media bus format %d\n",203 bus_format);204 break;205 }206 }207 208 if (connector->display_info.bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE)209 dpi_c |= DPI_PIXEL_CLK_INVERT;210 211 if (connector->display_info.bus_flags & DRM_BUS_FLAG_DE_LOW)212 dpi_c |= DPI_OUTPUT_ENABLE_INVERT;213 }214 215 if (mode->flags & DRM_MODE_FLAG_CSYNC) {216 if (mode->flags & DRM_MODE_FLAG_NCSYNC)217 dpi_c |= DPI_OUTPUT_ENABLE_INVERT;218 } else {219 dpi_c |= DPI_OUTPUT_ENABLE_MODE;220 221 if (mode->flags & DRM_MODE_FLAG_NHSYNC)222 dpi_c |= DPI_HSYNC_INVERT;223 else if (!(mode->flags & DRM_MODE_FLAG_PHSYNC))224 dpi_c |= DPI_HSYNC_DISABLE;225 226 if (mode->flags & DRM_MODE_FLAG_NVSYNC)227 dpi_c |= DPI_VSYNC_INVERT;228 else if (!(mode->flags & DRM_MODE_FLAG_PVSYNC))229 dpi_c |= DPI_VSYNC_DISABLE;230 }231 232 if (!drm_dev_enter(dev, &idx))233 return;234 235 DPI_WRITE(DPI_C, dpi_c);236 237 ret = clk_set_rate(dpi->pixel_clock, mode->clock * 1000);238 if (ret)239 drm_err(dev, "Failed to set clock rate: %d\n", ret);240 241 ret = clk_prepare_enable(dpi->pixel_clock);242 if (ret)243 drm_err(dev, "Failed to set clock rate: %d\n", ret);244 245 drm_dev_exit(idx);246}247 248static enum drm_mode_status vc4_dpi_encoder_mode_valid(struct drm_encoder *encoder,249 const struct drm_display_mode *mode)250{251 if (mode->flags & DRM_MODE_FLAG_INTERLACE)252 return MODE_NO_INTERLACE;253 254 return MODE_OK;255}256 257static const struct drm_encoder_helper_funcs vc4_dpi_encoder_helper_funcs = {258 .disable = vc4_dpi_encoder_disable,259 .enable = vc4_dpi_encoder_enable,260 .mode_valid = vc4_dpi_encoder_mode_valid,261};262 263static int vc4_dpi_late_register(struct drm_encoder *encoder)264{265 struct drm_device *drm = encoder->dev;266 struct vc4_dpi *dpi = to_vc4_dpi(encoder);267 268 vc4_debugfs_add_regset32(drm, "dpi_regs", &dpi->regset);269 270 return 0;271}272 273static const struct drm_encoder_funcs vc4_dpi_encoder_funcs = {274 .late_register = vc4_dpi_late_register,275};276 277static const struct of_device_id vc4_dpi_dt_match[] = {278 { .compatible = "brcm,bcm2835-dpi", .data = NULL },279 {}280};281 282/* Sets up the next link in the display chain, whether it's a panel or283 * a bridge.284 */285static int vc4_dpi_init_bridge(struct vc4_dpi *dpi)286{287 struct drm_device *drm = dpi->encoder.base.dev;288 struct device *dev = &dpi->pdev->dev;289 struct drm_bridge *bridge;290 291 bridge = drmm_of_get_bridge(drm, dev->of_node, 0, 0);292 if (IS_ERR(bridge)) {293 /* If nothing was connected in the DT, that's not an294 * error.295 */296 if (PTR_ERR(bridge) == -ENODEV)297 return 0;298 else299 return PTR_ERR(bridge);300 }301 302 return drm_bridge_attach(&dpi->encoder.base, bridge, NULL, 0);303}304 305static void vc4_dpi_disable_clock(void *ptr)306{307 struct vc4_dpi *dpi = ptr;308 309 clk_disable_unprepare(dpi->core_clock);310}311 312static int vc4_dpi_bind(struct device *dev, struct device *master, void *data)313{314 struct platform_device *pdev = to_platform_device(dev);315 struct drm_device *drm = dev_get_drvdata(master);316 struct vc4_dpi *dpi;317 int ret;318 319 dpi = drmm_kzalloc(drm, sizeof(*dpi), GFP_KERNEL);320 if (!dpi)321 return -ENOMEM;322 323 dpi->encoder.type = VC4_ENCODER_TYPE_DPI;324 dpi->pdev = pdev;325 dpi->regs = vc4_ioremap_regs(pdev, 0);326 if (IS_ERR(dpi->regs))327 return PTR_ERR(dpi->regs);328 dpi->regset.base = dpi->regs;329 dpi->regset.regs = dpi_regs;330 dpi->regset.nregs = ARRAY_SIZE(dpi_regs);331 332 if (DPI_READ(DPI_ID) != DPI_ID_VALUE) {333 dev_err(dev, "Port returned 0x%08x for ID instead of 0x%08x\n",334 DPI_READ(DPI_ID), DPI_ID_VALUE);335 return -ENODEV;336 }337 338 dpi->core_clock = devm_clk_get(dev, "core");339 if (IS_ERR(dpi->core_clock)) {340 ret = PTR_ERR(dpi->core_clock);341 if (ret != -EPROBE_DEFER)342 drm_err(drm, "Failed to get core clock: %d\n", ret);343 return ret;344 }345 346 dpi->pixel_clock = devm_clk_get(dev, "pixel");347 if (IS_ERR(dpi->pixel_clock)) {348 ret = PTR_ERR(dpi->pixel_clock);349 if (ret != -EPROBE_DEFER)350 drm_err(drm, "Failed to get pixel clock: %d\n", ret);351 return ret;352 }353 354 ret = clk_prepare_enable(dpi->core_clock);355 if (ret) {356 drm_err(drm, "Failed to turn on core clock: %d\n", ret);357 return ret;358 }359 360 ret = devm_add_action_or_reset(dev, vc4_dpi_disable_clock, dpi);361 if (ret)362 return ret;363 364 ret = drmm_encoder_init(drm, &dpi->encoder.base,365 &vc4_dpi_encoder_funcs,366 DRM_MODE_ENCODER_DPI,367 NULL);368 if (ret)369 return ret;370 371 drm_encoder_helper_add(&dpi->encoder.base, &vc4_dpi_encoder_helper_funcs);372 373 ret = vc4_dpi_init_bridge(dpi);374 if (ret)375 return ret;376 377 dev_set_drvdata(dev, dpi);378 379 return 0;380}381 382static const struct component_ops vc4_dpi_ops = {383 .bind = vc4_dpi_bind,384};385 386static int vc4_dpi_dev_probe(struct platform_device *pdev)387{388 return component_add(&pdev->dev, &vc4_dpi_ops);389}390 391static void vc4_dpi_dev_remove(struct platform_device *pdev)392{393 component_del(&pdev->dev, &vc4_dpi_ops);394}395 396struct platform_driver vc4_dpi_driver = {397 .probe = vc4_dpi_dev_probe,398 .remove_new = vc4_dpi_dev_remove,399 .driver = {400 .name = "vc4_dpi",401 .of_match_table = vc4_dpi_dt_match,402 },403};404