// 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/mod_devicetable.h>
#include <linux/platform_device.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;
};
#define to_vc4_dpi(_encoder) \
container_of_const(_encoder, struct vc4_dpi, encoder.base)
#define DPI_READ(offset) \
({ \
kunit_fail_current_test("Accessing a register in a unit test!\n"); \
readl(dpi->regs + (offset)); \
})
#define DPI_WRITE(offset, val) \
do { \
kunit_fail_current_test("Accessing a register in a unit test!\n"); \
writel(val, dpi->regs + (offset)); \
} while (0)
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 18bit if no connector or format found. */
dpi_c |= VC4_SET_FIELD(DPI_FORMAT_18BIT_666_RGB_1, 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_BGR666_1X24_CPADHI:
dpi_c |= VC4_SET_FIELD(DPI_ORDER_BGR, DPI_ORDER);
fallthrough;
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_BGR666_1X18:
dpi_c |= VC4_SET_FIELD(DPI_ORDER_BGR, DPI_ORDER);
fallthrough;
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;
case MEDIA_BUS_FMT_RGB565_1X24_CPADHI:
dpi_c |= VC4_SET_FIELD(DPI_FORMAT_16BIT_565_RGB_2,
DPI_FORMAT);
break;
default:
drm_err(dev, "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_err(dev, "Failed to set clock rate: %d\n", ret);
ret = clk_prepare_enable(dpi->pixel_clock);
if (ret)
drm_err(dev, "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);
vc4_debugfs_add_regset32(drm, "dpi_regs", &dpi->regset);
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_err(drm, "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_err(drm, "Failed to get pixel clock: %d\n", ret);
return ret;
}
ret = clk_prepare_enable(dpi->core_clock);
if (ret) {
drm_err(drm, "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 void vc4_dpi_dev_remove(struct platform_device *pdev)
{
component_del(&pdev->dev, &vc4_dpi_ops);
}
struct platform_driver vc4_dpi_driver = {
.probe = vc4_dpi_dev_probe,
.remove_new = vc4_dpi_dev_remove,
.driver = {
.name = "vc4_dpi",
.of_match_table = vc4_dpi_dt_match,
},
};
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