diff options
Diffstat (limited to 'drivers/gpu/drm/vc4/vc4_dpi.c')
| -rw-r--r-- | drivers/gpu/drm/vc4/vc4_dpi.c | 391 |
1 files changed, 391 insertions, 0 deletions
diff --git a/drivers/gpu/drm/vc4/vc4_dpi.c b/drivers/gpu/drm/vc4/vc4_dpi.c new file mode 100644 index 000000000..61ef7d232 --- /dev/null +++ b/drivers/gpu/drm/vc4/vc4_dpi.c @@ -0,0 +1,391 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2016 Broadcom Limited + */ + +/** + * DOC: VC4 DPI module + * + * The VC4 DPI hardware supports MIPI DPI type 4 and Nokia ViSSI + * signals. On BCM2835, these can be routed out to GPIO0-27 with the + * ALT2 function. + */ + +#include <drm/drm_atomic_helper.h> +#include <drm/drm_bridge.h> +#include <drm/drm_drv.h> +#include <drm/drm_edid.h> +#include <drm/drm_of.h> +#include <drm/drm_panel.h> +#include <drm/drm_probe_helper.h> +#include <drm/drm_simple_kms_helper.h> +#include <linux/clk.h> +#include <linux/component.h> +#include <linux/media-bus-format.h> +#include <linux/of_graph.h> +#include <linux/of_platform.h> +#include "vc4_drv.h" +#include "vc4_regs.h" + +#define DPI_C 0x00 +# define DPI_OUTPUT_ENABLE_MODE BIT(16) + +/* The order field takes the incoming 24 bit RGB from the pixel valve + * and shuffles the 3 channels. + */ +# define DPI_ORDER_MASK VC4_MASK(15, 14) +# define DPI_ORDER_SHIFT 14 +# define DPI_ORDER_RGB 0 +# define DPI_ORDER_BGR 1 +# define DPI_ORDER_GRB 2 +# define DPI_ORDER_BRG 3 + +/* The format field takes the ORDER-shuffled pixel valve data and + * formats it onto the output lines. + */ +# define DPI_FORMAT_MASK VC4_MASK(13, 11) +# define DPI_FORMAT_SHIFT 11 +/* This define is named in the hardware, but actually just outputs 0. */ +# define DPI_FORMAT_9BIT_666_RGB 0 +/* Outputs 00000000rrrrrggggggbbbbb */ +# define DPI_FORMAT_16BIT_565_RGB_1 1 +/* Outputs 000rrrrr00gggggg000bbbbb */ +# define DPI_FORMAT_16BIT_565_RGB_2 2 +/* Outputs 00rrrrr000gggggg00bbbbb0 */ +# define DPI_FORMAT_16BIT_565_RGB_3 3 +/* Outputs 000000rrrrrrggggggbbbbbb */ +# define DPI_FORMAT_18BIT_666_RGB_1 4 +/* Outputs 00rrrrrr00gggggg00bbbbbb */ +# define DPI_FORMAT_18BIT_666_RGB_2 5 +/* Outputs rrrrrrrrggggggggbbbbbbbb */ +# define DPI_FORMAT_24BIT_888_RGB 6 + +/* Reverses the polarity of the corresponding signal */ +# define DPI_PIXEL_CLK_INVERT BIT(10) +# define DPI_HSYNC_INVERT BIT(9) +# define DPI_VSYNC_INVERT BIT(8) +# define DPI_OUTPUT_ENABLE_INVERT BIT(7) + +/* Outputs the signal the falling clock edge instead of rising. */ +# define DPI_HSYNC_NEGATE BIT(6) +# define DPI_VSYNC_NEGATE BIT(5) +# define DPI_OUTPUT_ENABLE_NEGATE BIT(4) + +/* Disables the signal */ +# define DPI_HSYNC_DISABLE BIT(3) +# define DPI_VSYNC_DISABLE BIT(2) +# define DPI_OUTPUT_ENABLE_DISABLE BIT(1) + +/* Power gate to the device, full reset at 0 -> 1 transition */ +# define DPI_ENABLE BIT(0) + +/* All other registers besides DPI_C return the ID */ +#define DPI_ID 0x04 +# define DPI_ID_VALUE 0x00647069 + +/* General DPI hardware state. */ +struct vc4_dpi { + struct vc4_encoder encoder; + + struct platform_device *pdev; + + void __iomem *regs; + + struct clk *pixel_clock; + struct clk *core_clock; + + struct debugfs_regset32 regset; +}; + +static inline struct vc4_dpi * +to_vc4_dpi(struct drm_encoder *encoder) +{ + return container_of(encoder, struct vc4_dpi, encoder.base); +} + +#define DPI_READ(offset) readl(dpi->regs + (offset)) +#define DPI_WRITE(offset, val) writel(val, dpi->regs + (offset)) + +static const struct debugfs_reg32 dpi_regs[] = { + VC4_REG32(DPI_C), + VC4_REG32(DPI_ID), +}; + +static void vc4_dpi_encoder_disable(struct drm_encoder *encoder) +{ + struct drm_device *dev = encoder->dev; + struct vc4_dpi *dpi = to_vc4_dpi(encoder); + int idx; + + if (!drm_dev_enter(dev, &idx)) + return; + + clk_disable_unprepare(dpi->pixel_clock); + + drm_dev_exit(idx); +} + +static void vc4_dpi_encoder_enable(struct drm_encoder *encoder) +{ + struct drm_device *dev = encoder->dev; + struct drm_display_mode *mode = &encoder->crtc->mode; + struct vc4_dpi *dpi = to_vc4_dpi(encoder); + struct drm_connector_list_iter conn_iter; + struct drm_connector *connector = NULL, *connector_scan; + u32 dpi_c = DPI_ENABLE; + int idx; + int ret; + + /* Look up the connector attached to DPI so we can get the + * bus_format. Ideally the bridge would tell us the + * bus_format we want, but it doesn't yet, so assume that it's + * uniform throughout the bridge chain. + */ + drm_connector_list_iter_begin(dev, &conn_iter); + drm_for_each_connector_iter(connector_scan, &conn_iter) { + if (connector_scan->encoder == encoder) { + connector = connector_scan; + break; + } + } + drm_connector_list_iter_end(&conn_iter); + + /* Default to 24bit if no connector or format found. */ + dpi_c |= VC4_SET_FIELD(DPI_FORMAT_24BIT_888_RGB, DPI_FORMAT); + + if (connector) { + if (connector->display_info.num_bus_formats) { + u32 bus_format = connector->display_info.bus_formats[0]; + + dpi_c &= ~DPI_FORMAT_MASK; + + switch (bus_format) { + case MEDIA_BUS_FMT_RGB888_1X24: + dpi_c |= VC4_SET_FIELD(DPI_FORMAT_24BIT_888_RGB, + DPI_FORMAT); + break; + case MEDIA_BUS_FMT_BGR888_1X24: + dpi_c |= VC4_SET_FIELD(DPI_FORMAT_24BIT_888_RGB, + DPI_FORMAT); + dpi_c |= VC4_SET_FIELD(DPI_ORDER_BGR, + DPI_ORDER); + break; + case MEDIA_BUS_FMT_RGB666_1X24_CPADHI: + dpi_c |= VC4_SET_FIELD(DPI_FORMAT_18BIT_666_RGB_2, + DPI_FORMAT); + break; + case MEDIA_BUS_FMT_RGB666_1X18: + dpi_c |= VC4_SET_FIELD(DPI_FORMAT_18BIT_666_RGB_1, + DPI_FORMAT); + break; + case MEDIA_BUS_FMT_RGB565_1X16: + dpi_c |= VC4_SET_FIELD(DPI_FORMAT_16BIT_565_RGB_1, + DPI_FORMAT); + break; + default: + DRM_ERROR("Unknown media bus format %d\n", + bus_format); + break; + } + } + + if (connector->display_info.bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE) + dpi_c |= DPI_PIXEL_CLK_INVERT; + + if (connector->display_info.bus_flags & DRM_BUS_FLAG_DE_LOW) + dpi_c |= DPI_OUTPUT_ENABLE_INVERT; + } + + if (mode->flags & DRM_MODE_FLAG_CSYNC) { + if (mode->flags & DRM_MODE_FLAG_NCSYNC) + dpi_c |= DPI_OUTPUT_ENABLE_INVERT; + } else { + dpi_c |= DPI_OUTPUT_ENABLE_MODE; + + if (mode->flags & DRM_MODE_FLAG_NHSYNC) + dpi_c |= DPI_HSYNC_INVERT; + else if (!(mode->flags & DRM_MODE_FLAG_PHSYNC)) + dpi_c |= DPI_HSYNC_DISABLE; + + if (mode->flags & DRM_MODE_FLAG_NVSYNC) + dpi_c |= DPI_VSYNC_INVERT; + else if (!(mode->flags & DRM_MODE_FLAG_PVSYNC)) + dpi_c |= DPI_VSYNC_DISABLE; + } + + if (!drm_dev_enter(dev, &idx)) + return; + + DPI_WRITE(DPI_C, dpi_c); + + ret = clk_set_rate(dpi->pixel_clock, mode->clock * 1000); + if (ret) + DRM_ERROR("Failed to set clock rate: %d\n", ret); + + ret = clk_prepare_enable(dpi->pixel_clock); + if (ret) + DRM_ERROR("Failed to set clock rate: %d\n", ret); + + drm_dev_exit(idx); +} + +static enum drm_mode_status vc4_dpi_encoder_mode_valid(struct drm_encoder *encoder, + const struct drm_display_mode *mode) +{ + if (mode->flags & DRM_MODE_FLAG_INTERLACE) + return MODE_NO_INTERLACE; + + return MODE_OK; +} + +static const struct drm_encoder_helper_funcs vc4_dpi_encoder_helper_funcs = { + .disable = vc4_dpi_encoder_disable, + .enable = vc4_dpi_encoder_enable, + .mode_valid = vc4_dpi_encoder_mode_valid, +}; + +static int vc4_dpi_late_register(struct drm_encoder *encoder) +{ + struct drm_device *drm = encoder->dev; + struct vc4_dpi *dpi = to_vc4_dpi(encoder); + int ret; + + ret = vc4_debugfs_add_regset32(drm->primary, "dpi_regs", &dpi->regset); + if (ret) + return ret; + + return 0; +} + +static const struct drm_encoder_funcs vc4_dpi_encoder_funcs = { + .late_register = vc4_dpi_late_register, +}; + +static const struct of_device_id vc4_dpi_dt_match[] = { + { .compatible = "brcm,bcm2835-dpi", .data = NULL }, + {} +}; + +/* Sets up the next link in the display chain, whether it's a panel or + * a bridge. + */ +static int vc4_dpi_init_bridge(struct vc4_dpi *dpi) +{ + struct drm_device *drm = dpi->encoder.base.dev; + struct device *dev = &dpi->pdev->dev; + struct drm_bridge *bridge; + + bridge = drmm_of_get_bridge(drm, dev->of_node, 0, 0); + if (IS_ERR(bridge)) { + /* If nothing was connected in the DT, that's not an + * error. + */ + if (PTR_ERR(bridge) == -ENODEV) + return 0; + else + return PTR_ERR(bridge); + } + + return drm_bridge_attach(&dpi->encoder.base, bridge, NULL, 0); +} + +static void vc4_dpi_disable_clock(void *ptr) +{ + struct vc4_dpi *dpi = ptr; + + clk_disable_unprepare(dpi->core_clock); +} + +static int vc4_dpi_bind(struct device *dev, struct device *master, void *data) +{ + struct platform_device *pdev = to_platform_device(dev); + struct drm_device *drm = dev_get_drvdata(master); + struct vc4_dpi *dpi; + int ret; + + dpi = drmm_kzalloc(drm, sizeof(*dpi), GFP_KERNEL); + if (!dpi) + return -ENOMEM; + + dpi->encoder.type = VC4_ENCODER_TYPE_DPI; + dpi->pdev = pdev; + dpi->regs = vc4_ioremap_regs(pdev, 0); + if (IS_ERR(dpi->regs)) + return PTR_ERR(dpi->regs); + dpi->regset.base = dpi->regs; + dpi->regset.regs = dpi_regs; + dpi->regset.nregs = ARRAY_SIZE(dpi_regs); + + if (DPI_READ(DPI_ID) != DPI_ID_VALUE) { + dev_err(dev, "Port returned 0x%08x for ID instead of 0x%08x\n", + DPI_READ(DPI_ID), DPI_ID_VALUE); + return -ENODEV; + } + + dpi->core_clock = devm_clk_get(dev, "core"); + if (IS_ERR(dpi->core_clock)) { + ret = PTR_ERR(dpi->core_clock); + if (ret != -EPROBE_DEFER) + DRM_ERROR("Failed to get core clock: %d\n", ret); + return ret; + } + + dpi->pixel_clock = devm_clk_get(dev, "pixel"); + if (IS_ERR(dpi->pixel_clock)) { + ret = PTR_ERR(dpi->pixel_clock); + if (ret != -EPROBE_DEFER) + DRM_ERROR("Failed to get pixel clock: %d\n", ret); + return ret; + } + + ret = clk_prepare_enable(dpi->core_clock); + if (ret) { + DRM_ERROR("Failed to turn on core clock: %d\n", ret); + return ret; + } + + ret = devm_add_action_or_reset(dev, vc4_dpi_disable_clock, dpi); + if (ret) + return ret; + + ret = drmm_encoder_init(drm, &dpi->encoder.base, + &vc4_dpi_encoder_funcs, + DRM_MODE_ENCODER_DPI, + NULL); + if (ret) + return ret; + + drm_encoder_helper_add(&dpi->encoder.base, &vc4_dpi_encoder_helper_funcs); + + ret = vc4_dpi_init_bridge(dpi); + if (ret) + return ret; + + dev_set_drvdata(dev, dpi); + + return 0; +} + +static const struct component_ops vc4_dpi_ops = { + .bind = vc4_dpi_bind, +}; + +static int vc4_dpi_dev_probe(struct platform_device *pdev) +{ + return component_add(&pdev->dev, &vc4_dpi_ops); +} + +static int vc4_dpi_dev_remove(struct platform_device *pdev) +{ + component_del(&pdev->dev, &vc4_dpi_ops); + return 0; +} + +struct platform_driver vc4_dpi_driver = { + .probe = vc4_dpi_dev_probe, + .remove = vc4_dpi_dev_remove, + .driver = { + .name = "vc4_dpi", + .of_match_table = vc4_dpi_dt_match, + }, +}; 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