diff options
author | Eric Anholt <eric@anholt.net> | 2016-02-10 11:42:32 -0800 |
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committer | Eric Anholt <eric@anholt.net> | 2016-04-14 12:22:53 -0700 |
commit | 08302c35b59d306ff37b996e56fb2a488c1d2c2e (patch) | |
tree | 869cb7794b855310b934dc26bffe39f05d830577 /drivers/gpu/drm/vc4/vc4_dpi.c | |
parent | 0b27c02a7f1c697694f2ad6d6517e7dbf9ecfa39 (diff) | |
download | op-kernel-dev-08302c35b59d306ff37b996e56fb2a488c1d2c2e.zip op-kernel-dev-08302c35b59d306ff37b996e56fb2a488c1d2c2e.tar.gz |
drm/vc4: Add DPI driver
The DPI interface involves taking a ton of our GPIOs to be used as
outputs, and routing display signals over them in parallel.
v2: Use display_info.bus_formats[] to replace our custom DT
properties.
v3: Rebase on V3D documentation changes.
v4: Fix rebase detritus from V3D documentation changes.
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Rob Herring <robh@kernel.org>
Diffstat (limited to 'drivers/gpu/drm/vc4/vc4_dpi.c')
-rw-r--r-- | drivers/gpu/drm/vc4/vc4_dpi.c | 520 |
1 files changed, 520 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 0000000..9817dbf --- /dev/null +++ b/drivers/gpu/drm/vc4/vc4_dpi.c @@ -0,0 +1,520 @@ +/* + * Copyright (C) 2016 Broadcom Limited + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ + +/** + * DOC: VC4 DPI module + * + * The VC4 DPI hardware supports MIPI DPI type 4 and Nokia ViSSI + * signals, which are routed out to GPIO0-27 with the ALT2 function. + */ + +#include "drm_atomic_helper.h" +#include "drm_crtc_helper.h" +#include "drm_edid.h" +#include "drm_panel.h" +#include "linux/clk.h" +#include "linux/component.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 platform_device *pdev; + + struct drm_encoder *encoder; + struct drm_connector *connector; + struct drm_panel *panel; + + void __iomem *regs; + + struct clk *pixel_clock; + struct clk *core_clock; +}; + +#define DPI_READ(offset) readl(dpi->regs + (offset)) +#define DPI_WRITE(offset, val) writel(val, dpi->regs + (offset)) + +/* VC4 DPI encoder KMS struct */ +struct vc4_dpi_encoder { + struct vc4_encoder base; + struct vc4_dpi *dpi; +}; + +static inline struct vc4_dpi_encoder * +to_vc4_dpi_encoder(struct drm_encoder *encoder) +{ + return container_of(encoder, struct vc4_dpi_encoder, base.base); +} + +/* VC4 DPI connector KMS struct */ +struct vc4_dpi_connector { + struct drm_connector base; + struct vc4_dpi *dpi; + + /* Since the connector is attached to just the one encoder, + * this is the reference to it so we can do the best_encoder() + * hook. + */ + struct drm_encoder *encoder; +}; + +static inline struct vc4_dpi_connector * +to_vc4_dpi_connector(struct drm_connector *connector) +{ + return container_of(connector, struct vc4_dpi_connector, base); +} + +#define DPI_REG(reg) { reg, #reg } +static const struct { + u32 reg; + const char *name; +} dpi_regs[] = { + DPI_REG(DPI_C), + DPI_REG(DPI_ID), +}; + +static void vc4_dpi_dump_regs(struct vc4_dpi *dpi) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(dpi_regs); i++) { + DRM_INFO("0x%04x (%s): 0x%08x\n", + dpi_regs[i].reg, dpi_regs[i].name, + DPI_READ(dpi_regs[i].reg)); + } +} + +#ifdef CONFIG_DEBUG_FS +int vc4_dpi_debugfs_regs(struct seq_file *m, void *unused) +{ + struct drm_info_node *node = (struct drm_info_node *)m->private; + struct drm_device *dev = node->minor->dev; + struct vc4_dev *vc4 = to_vc4_dev(dev); + struct vc4_dpi *dpi = vc4->dpi; + int i; + + if (!dpi) + return 0; + + for (i = 0; i < ARRAY_SIZE(dpi_regs); i++) { + seq_printf(m, "%s (0x%04x): 0x%08x\n", + dpi_regs[i].name, dpi_regs[i].reg, + DPI_READ(dpi_regs[i].reg)); + } + + return 0; +} +#endif + +static enum drm_connector_status +vc4_dpi_connector_detect(struct drm_connector *connector, bool force) +{ + struct vc4_dpi_connector *vc4_connector = + to_vc4_dpi_connector(connector); + struct vc4_dpi *dpi = vc4_connector->dpi; + + if (dpi->panel) + return connector_status_connected; + else + return connector_status_disconnected; +} + +static void vc4_dpi_connector_destroy(struct drm_connector *connector) +{ + drm_connector_unregister(connector); + drm_connector_cleanup(connector); +} + +static int vc4_dpi_connector_get_modes(struct drm_connector *connector) +{ + struct vc4_dpi_connector *vc4_connector = + to_vc4_dpi_connector(connector); + struct vc4_dpi *dpi = vc4_connector->dpi; + + if (dpi->panel) + return drm_panel_get_modes(dpi->panel); + + return 0; +} + +static struct drm_encoder * +vc4_dpi_connector_best_encoder(struct drm_connector *connector) +{ + struct vc4_dpi_connector *dpi_connector = + to_vc4_dpi_connector(connector); + return dpi_connector->encoder; +} + +static const struct drm_connector_funcs vc4_dpi_connector_funcs = { + .dpms = drm_atomic_helper_connector_dpms, + .detect = vc4_dpi_connector_detect, + .fill_modes = drm_helper_probe_single_connector_modes, + .destroy = vc4_dpi_connector_destroy, + .reset = drm_atomic_helper_connector_reset, + .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, +}; + +static const struct drm_connector_helper_funcs vc4_dpi_connector_helper_funcs = { + .get_modes = vc4_dpi_connector_get_modes, + .best_encoder = vc4_dpi_connector_best_encoder, +}; + +static struct drm_connector *vc4_dpi_connector_init(struct drm_device *dev, + struct vc4_dpi *dpi) +{ + struct drm_connector *connector = NULL; + struct vc4_dpi_connector *dpi_connector; + int ret = 0; + + dpi_connector = devm_kzalloc(dev->dev, sizeof(*dpi_connector), + GFP_KERNEL); + if (!dpi_connector) { + ret = -ENOMEM; + goto fail; + } + connector = &dpi_connector->base; + + dpi_connector->encoder = dpi->encoder; + dpi_connector->dpi = dpi; + + drm_connector_init(dev, connector, &vc4_dpi_connector_funcs, + DRM_MODE_CONNECTOR_DPI); + drm_connector_helper_add(connector, &vc4_dpi_connector_helper_funcs); + + connector->polled = 0; + connector->interlace_allowed = 0; + connector->doublescan_allowed = 0; + + drm_mode_connector_attach_encoder(connector, dpi->encoder); + + return connector; + + fail: + if (connector) + vc4_dpi_connector_destroy(connector); + + return ERR_PTR(ret); +} + +static const struct drm_encoder_funcs vc4_dpi_encoder_funcs = { + .destroy = drm_encoder_cleanup, +}; + +static void vc4_dpi_encoder_disable(struct drm_encoder *encoder) +{ + struct vc4_dpi_encoder *vc4_encoder = to_vc4_dpi_encoder(encoder); + struct vc4_dpi *dpi = vc4_encoder->dpi; + + drm_panel_disable(dpi->panel); + + clk_disable_unprepare(dpi->pixel_clock); + + drm_panel_unprepare(dpi->panel); +} + +static void vc4_dpi_encoder_enable(struct drm_encoder *encoder) +{ + struct drm_display_mode *mode = &encoder->crtc->mode; + struct vc4_dpi_encoder *vc4_encoder = to_vc4_dpi_encoder(encoder); + struct vc4_dpi *dpi = vc4_encoder->dpi; + u32 dpi_c = DPI_ENABLE | DPI_OUTPUT_ENABLE_MODE; + int ret; + + ret = drm_panel_prepare(dpi->panel); + if (ret) { + DRM_ERROR("Panel failed to prepare\n"); + return; + } + + if (dpi->connector->display_info.num_bus_formats) { + u32 bus_format = dpi->connector->display_info.bus_formats[0]; + + 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_3, + DPI_FORMAT); + break; + default: + DRM_ERROR("Unknown media bus format %d\n", bus_format); + break; + } + } + + 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; + + 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); + + ret = drm_panel_enable(dpi->panel); + if (ret) { + DRM_ERROR("Panel failed to enable\n"); + drm_panel_unprepare(dpi->panel); + return; + } +} + +static const struct drm_encoder_helper_funcs vc4_dpi_encoder_helper_funcs = { + .disable = vc4_dpi_encoder_disable, + .enable = vc4_dpi_encoder_enable, +}; + +static const struct of_device_id vc4_dpi_dt_match[] = { + { .compatible = "brcm,bcm2835-dpi", .data = NULL }, + {} +}; + +/* Walks the OF graph to find the panel node and then asks DRM to look + * up the panel. + */ +static struct drm_panel *vc4_dpi_get_panel(struct device *dev) +{ + struct device_node *endpoint, *panel_node; + struct device_node *np = dev->of_node; + struct drm_panel *panel; + + endpoint = of_graph_get_next_endpoint(np, NULL); + if (!endpoint) { + dev_err(dev, "no endpoint to fetch DPI panel\n"); + return NULL; + } + + /* don't proceed if we have an endpoint but no panel_node tied to it */ + panel_node = of_graph_get_remote_port_parent(endpoint); + of_node_put(endpoint); + if (!panel_node) { + dev_err(dev, "no valid panel node\n"); + return NULL; + } + + panel = of_drm_find_panel(panel_node); + of_node_put(panel_node); + + return panel; +} + +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_dev *vc4 = to_vc4_dev(drm); + struct vc4_dpi *dpi; + struct vc4_dpi_encoder *vc4_dpi_encoder; + int ret; + + dpi = devm_kzalloc(dev, sizeof(*dpi), GFP_KERNEL); + if (!dpi) + return -ENOMEM; + + vc4_dpi_encoder = devm_kzalloc(dev, sizeof(*vc4_dpi_encoder), + GFP_KERNEL); + if (!vc4_dpi_encoder) + return -ENOMEM; + vc4_dpi_encoder->base.type = VC4_ENCODER_TYPE_DPI; + vc4_dpi_encoder->dpi = dpi; + dpi->encoder = &vc4_dpi_encoder->base.base; + + dpi->pdev = pdev; + dpi->regs = vc4_ioremap_regs(pdev, 0); + if (IS_ERR(dpi->regs)) + return PTR_ERR(dpi->regs); + + vc4_dpi_dump_regs(dpi); + + 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); + + dpi->panel = vc4_dpi_get_panel(dev); + + drm_encoder_init(drm, dpi->encoder, &vc4_dpi_encoder_funcs, + DRM_MODE_ENCODER_DPI, NULL); + drm_encoder_helper_add(dpi->encoder, &vc4_dpi_encoder_helper_funcs); + + dpi->connector = vc4_dpi_connector_init(drm, dpi); + if (IS_ERR(dpi->connector)) { + ret = PTR_ERR(dpi->connector); + goto err_destroy_encoder; + } + + if (dpi->panel) + drm_panel_attach(dpi->panel, dpi->connector); + + dev_set_drvdata(dev, dpi); + + vc4->dpi = dpi; + + return 0; + +err_destroy_encoder: + drm_encoder_cleanup(dpi->encoder); + clk_disable_unprepare(dpi->core_clock); + return ret; +} + +static void vc4_dpi_unbind(struct device *dev, struct device *master, + void *data) +{ + struct drm_device *drm = dev_get_drvdata(master); + struct vc4_dev *vc4 = to_vc4_dev(drm); + struct vc4_dpi *dpi = dev_get_drvdata(dev); + + if (dpi->panel) + drm_panel_detach(dpi->panel); + + vc4_dpi_connector_destroy(dpi->connector); + drm_encoder_cleanup(dpi->encoder); + + clk_disable_unprepare(dpi->core_clock); + + vc4->dpi = NULL; +} + +static const struct component_ops vc4_dpi_ops = { + .bind = vc4_dpi_bind, + .unbind = vc4_dpi_unbind, +}; + +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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