On Sun, Feb 23, 2025 at 07:30:25PM +0800, Andy Yan wrote:
> From: Andy Yan <andy.yan@xxxxxxxxxxxxxx>
>
> The DW DP TX Controller is compliant with the DisplayPort Specification
> Version 1.4 with the following features:
>
> * DisplayPort 1.4a
> * Main Link: 1/2/4 lanes
> * Main Link Support 1.62Gbps, 2.7Gbps, 5.4Gbps and 8.1Gbps
> * AUX channel 1Mbps
> * Single Stream Transport(SST)
> * Multistream Transport (MST)
> *Type-C support (alternate mode)
> * HDCP 2.2, HDCP 1.3
> * Supports up to 8/10 bits per color component
> * Supports RBG, YCbCr4:4:4, YCbCr4:2:2, YCbCr4:2:0
> * Pixel clock up to 594MHz
> * I2S, SPDIF audio interface
>
> Add library with common helpers to make it can be shared with
> other SoC.
>
> Signed-off-by: Andy Yan <andy.yan@xxxxxxxxxxxxxx>
>
> drm/bridge: cleanup
Stray line?
>
> ---
>
> drivers/gpu/drm/bridge/synopsys/Kconfig | 7 +
> drivers/gpu/drm/bridge/synopsys/Makefile | 1 +
> drivers/gpu/drm/bridge/synopsys/dw-dp.c | 2155 ++++++++++++++++++++++
> include/drm/bridge/dw_dp.h | 19 +
> 4 files changed, 2182 insertions(+)
> create mode 100644 drivers/gpu/drm/bridge/synopsys/dw-dp.c
> create mode 100644 include/drm/bridge/dw_dp.h
>
> diff --git a/drivers/gpu/drm/bridge/synopsys/Kconfig b/drivers/gpu/drm/bridge/synopsys/Kconfig
> index f3ab2f985f8c..2c5e532410de 100644
> --- a/drivers/gpu/drm/bridge/synopsys/Kconfig
> +++ b/drivers/gpu/drm/bridge/synopsys/Kconfig
> @@ -1,4 +1,11 @@
> # SPDX-License-Identifier: GPL-2.0-only
> +config DRM_DW_DP
> + tristate
> + select DRM_DISPLAY_HELPER
> + select DRM_DISPLAY_DP_HELPER
> + select DRM_KMS_HELPER
> + select REGMAP_MMIO
> +
> config DRM_DW_HDMI
> tristate
> select DRM_DISPLAY_HDMI_HELPER
> diff --git a/drivers/gpu/drm/bridge/synopsys/Makefile b/drivers/gpu/drm/bridge/synopsys/Makefile
> index 9dc376d220ad..4dada44029ac 100644
> --- a/drivers/gpu/drm/bridge/synopsys/Makefile
> +++ b/drivers/gpu/drm/bridge/synopsys/Makefile
> @@ -1,4 +1,5 @@
> # SPDX-License-Identifier: GPL-2.0-only
> +obj-$(CONFIG_DRM_DW_DP) += dw-dp.o
> obj-$(CONFIG_DRM_DW_HDMI) += dw-hdmi.o
> obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw-hdmi-ahb-audio.o
> obj-$(CONFIG_DRM_DW_HDMI_GP_AUDIO) += dw-hdmi-gp-audio.o
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-dp.c b/drivers/gpu/drm/bridge/synopsys/dw-dp.c
> new file mode 100644
> index 000000000000..6ecbe9851369
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-dp.c
> @@ -0,0 +1,2155 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Synopsys DesignWare Cores DisplayPort Transmitter Controller
> + *
> + * Copyright (c) 2024 Rockchip Electronics Co., Ltd.
> + *
> + * Author: Andy Yan <andy.yan@xxxxxxxxxxxxxx>
> + */
> +#include <linux/bitfield.h>
> +#include <linux/clk.h>
> +#include <linux/component.h>
> +#include <linux/iopoll.h>
> +#include <linux/irq.h>
> +#include <linux/of_device.h>
> +#include <linux/of_graph.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include <linux/phy/phy.h>
> +#include <linux/unaligned.h>
> +
> +#include <drm/bridge/dw_dp.h>
> +#include <drm/drm_atomic_helper.h>
> +#include <drm/drm_bridge.h>
> +#include <drm/drm_bridge_connector.h>
> +#include <drm/display/drm_dp_helper.h>
> +#include <drm/display/drm_hdmi_helper.h>
> +#include <drm/drm_edid.h>
> +#include <drm/drm_of.h>
> +#include <drm/drm_print.h>
> +#include <drm/drm_probe_helper.h>
> +#include <drm/drm_simple_kms_helper.h>
> +
> +#include <uapi/linux/media-bus-format.h>
> +
> +#define DW_DP_VERSION_NUMBER 0x0000
> +#define DW_DP_VERSION_TYPE 0x0004
> +#define DW_DP_ID 0x0008
> +
> +#define DW_DP_CONFIG_REG1 0x0100
> +#define DW_DP_CONFIG_REG2 0x0104
> +#define DW_DP_CONFIG_REG3 0x0108
> +
> +#define DW_DP_CCTL 0x0200
> +#define FORCE_HPD BIT(4)
> +#define DEFAULT_FAST_LINK_TRAIN_EN BIT(2)
> +#define ENHANCE_FRAMING_EN BIT(1)
> +#define SCRAMBLE_DIS BIT(0)
> +#define DW_DP_SOFT_RESET_CTRL 0x0204
> +#define VIDEO_RESET BIT(5)
> +#define AUX_RESET BIT(4)
> +#define AUDIO_SAMPLER_RESET BIT(3)
> +#define HDCP_MODULE_RESET BIT(2)
> +#define PHY_SOFT_RESET BIT(1)
> +#define CONTROLLER_RESET BIT(0)
> +
> +#define DW_DP_VSAMPLE_CTRL 0x0300
> +#define PIXEL_MODE_SELECT GENMASK(22, 21)
> +#define VIDEO_MAPPING GENMASK(20, 16)
> +#define VIDEO_STREAM_ENABLE BIT(5)
> +
> +#define DW_DP_VSAMPLE_STUFF_CTRL1 0x0304
> +
> +#define DW_DP_VSAMPLE_STUFF_CTRL2 0x0308
> +
> +#define DW_DP_VINPUT_POLARITY_CTRL 0x030c
> +#define DE_IN_POLARITY BIT(2)
> +#define HSYNC_IN_POLARITY BIT(1)
> +#define VSYNC_IN_POLARITY BIT(0)
> +
> +#define DW_DP_VIDEO_CONFIG1 0x0310
> +#define HACTIVE GENMASK(31, 16)
> +#define HBLANK GENMASK(15, 2)
> +#define I_P BIT(1)
> +#define R_V_BLANK_IN_OSC BIT(0)
> +
> +#define DW_DP_VIDEO_CONFIG2 0x0314
> +#define VBLANK GENMASK(31, 16)
> +#define VACTIVE GENMASK(15, 0)
> +
> +#define DW_DP_VIDEO_CONFIG3 0x0318
> +#define H_SYNC_WIDTH GENMASK(31, 16)
> +#define H_FRONT_PORCH GENMASK(15, 0)
> +
> +#define DW_DP_VIDEO_CONFIG4 0x031c
> +#define V_SYNC_WIDTH GENMASK(31, 16)
> +#define V_FRONT_PORCH GENMASK(15, 0)
> +
> +#define DW_DP_VIDEO_CONFIG5 0x0320
> +#define INIT_THRESHOLD_HI GENMASK(22, 21)
> +#define AVERAGE_BYTES_PER_TU_FRAC GENMASK(19, 16)
> +#define INIT_THRESHOLD GENMASK(13, 7)
> +#define AVERAGE_BYTES_PER_TU GENMASK(6, 0)
> +
> +#define DW_DP_VIDEO_MSA1 0x0324
> +#define VSTART GENMASK(31, 16)
> +#define HSTART GENMASK(15, 0)
> +
> +#define DW_DP_VIDEO_MSA2 0x0328
> +#define MISC0 GENMASK(31, 24)
> +
> +#define DW_DP_VIDEO_MSA3 0x032c
> +#define MISC1 GENMASK(31, 24)
> +
> +#define DW_DP_VIDEO_HBLANK_INTERVAL 0x0330
> +#define HBLANK_INTERVAL_EN BIT(16)
> +#define HBLANK_INTERVAL GENMASK(15, 0)
> +
> +#define DW_DP_AUD_CONFIG1 0x0400
> +#define AUDIO_TIMESTAMP_VERSION_NUM GENMASK(29, 24)
> +#define AUDIO_PACKET_ID GENMASK(23, 16)
> +#define AUDIO_MUTE BIT(15)
> +#define NUM_CHANNELS GENMASK(14, 12)
> +#define HBR_MODE_ENABLE BIT(10)
> +#define AUDIO_DATA_WIDTH GENMASK(9, 5)
> +#define AUDIO_DATA_IN_EN GENMASK(4, 1)
> +#define AUDIO_INF_SELECT BIT(0)
> +
> +#define DW_DP_SDP_VERTICAL_CTRL 0x0500
> +#define EN_VERTICAL_SDP BIT(2)
> +#define EN_AUDIO_STREAM_SDP BIT(1)
> +#define EN_AUDIO_TIMESTAMP_SDP BIT(0)
> +#define DW_DP_SDP_HORIZONTAL_CTRL 0x0504
> +#define EN_HORIZONTAL_SDP BIT(2)
> +#define DW_DP_SDP_STATUS_REGISTER 0x0508
> +#define DW_DP_SDP_MANUAL_CTRL 0x050c
> +#define DW_DP_SDP_STATUS_EN 0x0510
> +
> +#define DW_DP_SDP_REGISTER_BANK 0x0600
> +#define SDP_REGS GENMASK(31, 0)
> +
> +#define DW_DP_PHYIF_CTRL 0x0a00
> +#define PHY_WIDTH BIT(25)
> +#define PHY_POWERDOWN GENMASK(20, 17)
> +#define PHY_BUSY GENMASK(15, 12)
> +#define SSC_DIS BIT(16)
> +#define XMIT_ENABLE GENMASK(11, 8)
> +#define PHY_LANES GENMASK(7, 6)
> +#define PHY_RATE GENMASK(5, 4)
> +#define TPS_SEL GENMASK(3, 0)
> +
> +#define DW_DP_PHY_TX_EQ 0x0a04
> +#define DW_DP_CUSTOMPAT0 0x0a08
> +#define DW_DP_CUSTOMPAT1 0x0a0c
> +#define DW_DP_CUSTOMPAT2 0x0a10
> +#define DW_DP_HBR2_COMPLIANCE_SCRAMBLER_RESET 0x0a14
> +#define DW_DP_PHYIF_PWRDOWN_CTRL 0x0a18
> +
> +#define DW_DP_AUX_CMD 0x0b00
> +#define AUX_CMD_TYPE GENMASK(31, 28)
> +#define AUX_ADDR GENMASK(27, 8)
> +#define I2C_ADDR_ONLY BIT(4)
> +#define AUX_LEN_REQ GENMASK(3, 0)
> +
> +#define DW_DP_AUX_STATUS 0x0b04
> +#define AUX_TIMEOUT BIT(17)
> +#define AUX_BYTES_READ GENMASK(23, 19)
> +#define AUX_STATUS GENMASK(7, 4)
> +
> +#define DW_DP_AUX_DATA0 0x0b08
> +#define DW_DP_AUX_DATA1 0x0b0c
> +#define DW_DP_AUX_DATA2 0x0b10
> +#define DW_DP_AUX_DATA3 0x0b14
> +
> +#define DW_DP_GENERAL_INTERRUPT 0x0d00
> +#define VIDEO_FIFO_OVERFLOW_STREAM0 BIT(6)
> +#define AUDIO_FIFO_OVERFLOW_STREAM0 BIT(5)
> +#define SDP_EVENT_STREAM0 BIT(4)
> +#define AUX_CMD_INVALID BIT(3)
> +#define HDCP_EVENT BIT(2)
> +#define AUX_REPLY_EVENT BIT(1)
> +#define HPD_EVENT BIT(0)
> +
> +#define DW_DP_GENERAL_INTERRUPT_ENABLE 0x0d04
> +#define HDCP_EVENT_EN BIT(2)
> +#define AUX_REPLY_EVENT_EN BIT(1)
> +#define HPD_EVENT_EN BIT(0)
> +
> +#define DW_DP_HPD_STATUS 0x0d08
> +#define HPD_STATE GENMASK(11, 9)
> +#define HPD_STATUS BIT(8)
> +#define HPD_HOT_UNPLUG BIT(2)
> +#define HPD_HOT_PLUG BIT(1)
> +#define HPD_IRQ BIT(0)
> +
> +#define DW_DP_HPD_INTERRUPT_ENABLE 0x0d0c
> +#define HPD_UNPLUG_ERR_EN BIT(3)
> +#define HPD_UNPLUG_EN BIT(2)
> +#define HPD_PLUG_EN BIT(1)
> +#define HPD_IRQ_EN BIT(0)
> +
> +#define DW_DP_HDCP_CFG 0x0e00
> +#define DPCD12PLUS BIT(7)
> +#define CP_IRQ BIT(6)
> +#define BYPENCRYPTION BIT(5)
> +#define HDCP_LOCK BIT(4)
> +#define ENCRYPTIONDISABLE BIT(3)
> +#define ENABLE_HDCP_13 BIT(2)
> +#define ENABLE_HDCP BIT(1)
> +
> +#define DW_DP_HDCP_OBS 0x0e04
> +#define HDCP22_RE_AUTHENTICATION_REQ BIT(31)
> +#define HDCP22_AUTHENTICATION_FAILED BIT(30)
> +#define HDCP22_AUTHENTICATION_SUCCESS BIT(29)
> +#define HDCP22_CAPABLE_SINK BIT(28)
> +#define HDCP22_SINK_CAP_CHECK_COMPLETE BIT(27)
> +#define HDCP22_STATE GENMASK(26, 24)
> +#define HDCP22_BOOTED BIT(23)
> +#define HDCP13_BSTATUS GENMASK(22, 19)
> +#define REPEATER BIT(18)
> +#define HDCP_CAPABLE BIT(17)
> +#define STATEE GENMASK(16, 14)
> +#define STATEOEG GENMASK(13, 11)
> +#define STATER GENMASK(10, 8)
> +#define STATEA GENMASK(7, 4)
> +#define SUBSTATEA GENMASK(3, 1)
> +#define HDCPENGAGED BIT(0)
> +
> +#define DW_DP_HDCP_APIINTCLR 0x0e08
> +#define DW_DP_HDCP_APIINTSTAT 0x0e0c
> +#define DW_DP_HDCP_APIINTMSK 0x0e10
> +#define HDCP22_GPIOINT BIT(8)
> +#define HDCP_ENGAGED BIT(7)
> +#define HDCP_FAILED BIT(6)
> +#define KSVSHA1CALCDONEINT BIT(5)
> +#define AUXRESPNACK7TIMES BIT(4)
> +#define AUXRESPTIMEOUT BIT(3)
> +#define AUXRESPDEFER7TIMES BIT(2)
> +#define KSVACCESSINT BIT(0)
> +
> +#define DW_DP_HDCP_KSVMEMCTRL 0x0e18
> +#define KSVSHA1STATUS BIT(4)
> +#define KSVMEMACCESS BIT(1)
> +#define KSVMEMREQUEST BIT(0)
> +
> +#define DW_DP_HDCP_REG_BKSV0 0x3600
> +#define DW_DP_HDCP_REG_BKSV1 0x3604
> +#define DW_DP_HDCP_REG_ANCONF 0x3608
> +#define AN_BYPASS BIT(0)
> +
> +#define DW_DP_HDCP_REG_AN0 0x360c
> +#define DW_DP_HDCP_REG_AN1 0x3610
> +#define DW_DP_HDCP_REG_RMLCTL 0x3614
> +#define ODPK_DECRYPT_ENABLE BIT(0)
> +
> +#define DW_DP_HDCP_REG_RMLSTS 0x3618
> +#define IDPK_WR_OK_STS BIT(6)
> +#define IDPK_DATA_INDEX GENMASK(5, 0)
> +#define DW_DP_HDCP_REG_SEED 0x361c
> +#define DW_DP_HDCP_REG_DPK0 0x3620
> +#define DW_DP_HDCP_REG_DPK1 0x3624
> +#define DW_DP_HDCP22_GPIOSTS 0x3628
> +#define DW_DP_HDCP22_GPIOCHNGSTS 0x362c
> +#define DW_DP_HDCP_REG_DPK_CRC 0x3630
> +
> +#define DW_DP_MAX_REGISTER DW_DP_HDCP_REG_DPK_CRC
> +
> +#define SDP_REG_BANK_SIZE 16
> +
> +struct dw_dp_link_caps {
> + bool enhanced_framing;
> + bool tps3_supported;
> + bool tps4_supported;
> + bool fast_training;
> + bool channel_coding;
> + bool ssc;
> +};
> +
> +struct dw_dp_link_train_set {
> + unsigned int voltage_swing[4];
> + unsigned int pre_emphasis[4];
> + bool voltage_max_reached[4];
> + bool pre_max_reached[4];
> +};
> +
> +struct dw_dp_link_train {
> + struct dw_dp_link_train_set request;
> + struct dw_dp_link_train_set adjust;
> + bool clock_recovered;
> + bool channel_equalized;
> +};
> +
> +struct dw_dp_link {
> + u8 dpcd[DP_RECEIVER_CAP_SIZE];
> + unsigned char revision;
> + unsigned int rate;
> + unsigned int lanes;
> + u8 sink_count;
> + u8 vsc_sdp_supported;
> + struct dw_dp_link_caps caps;
> + struct dw_dp_link_train train;
> + struct drm_dp_desc desc;
> +};
> +
> +struct dw_dp_video {
> + struct drm_display_mode mode;
> + u8 video_mapping;
> + u8 pixel_mode;
> + u8 color_format;
> + u8 bpc;
> + u8 bpp;
> +};
> +
> +struct dw_dp_sdp {
> + struct dp_sdp_header header;
> + u8 db[32];
struct dp_sdp, please
> + unsigned long flags;
> +};
> +
> +struct dw_dp_hotplug {
> + bool long_hpd;
> +};
> +
> +struct dw_dp {
> + struct drm_bridge bridge;
> + struct device *dev;
> + struct regmap *regmap;
> + struct phy *phy;
> + struct clk *apb_clk;
> + struct clk *aux_clk;
> + struct clk *i2s_clk;
> + struct clk *spdif_clk;
> + struct clk *hdcp_clk;
> + struct reset_control *rstc;
> + struct completion complete;
> + int irq;
> + struct work_struct hpd_work;
> + struct dw_dp_hotplug hotplug;
> + struct mutex irq_lock;
> +
> + struct drm_dp_aux aux;
> +
> + struct dw_dp_link link;
> + struct dw_dp_video video;
> + const struct dw_dp_plat_data *plat_data;
> +
> + DECLARE_BITMAP(sdp_reg_bank, SDP_REG_BANK_SIZE);
> +};
> +
> +enum {
> + DW_DP_RGB_6BIT,
> + DW_DP_RGB_8BIT,
> + DW_DP_RGB_10BIT,
> + DW_DP_RGB_12BIT,
> + DW_DP_RGB_16BIT,
> + DW_DP_YCBCR444_8BIT,
> + DW_DP_YCBCR444_10BIT,
> + DW_DP_YCBCR444_12BIT,
> + DW_DP_YCBCR444_16BIT,
> + DW_DP_YCBCR422_8BIT,
> + DW_DP_YCBCR422_10BIT,
> + DW_DP_YCBCR422_12BIT,
> + DW_DP_YCBCR422_16BIT,
> + DW_DP_YCBCR420_8BIT,
> + DW_DP_YCBCR420_10BIT,
> + DW_DP_YCBCR420_12BIT,
> + DW_DP_YCBCR420_16BIT,
> +};
> +
> +enum {
> + DW_DP_MP_SINGLE_PIXEL,
> + DW_DP_MP_DUAL_PIXEL,
> + DW_DP_MP_QUAD_PIXEL,
> +};
> +
> +enum {
> + DW_DP_SDP_VERTICAL_INTERVAL = BIT(0),
> + DW_DP_SDP_HORIZONTAL_INTERVAL = BIT(1),
> +};
> +
> +enum {
> + DW_DP_HPD_STATE_IDLE,
> + DW_DP_HPD_STATE_UNPLUG,
> + DP_DP_HPD_STATE_TIMEOUT = 4,
> + DW_DP_HPD_STATE_PLUG = 7
> +};
> +
> +enum {
> + DW_DP_PHY_PATTERN_NONE,
> + DW_DP_PHY_PATTERN_TPS_1,
> + DW_DP_PHY_PATTERN_TPS_2,
> + DW_DP_PHY_PATTERN_TPS_3,
> + DW_DP_PHY_PATTERN_TPS_4,
> + DW_DP_PHY_PATTERN_SERM,
> + DW_DP_PHY_PATTERN_PBRS7,
> + DW_DP_PHY_PATTERN_CUSTOM_80BIT,
> + DW_DP_PHY_PATTERN_CP2520_1,
> + DW_DP_PHY_PATTERN_CP2520_2,
> +};
> +
> +struct dw_dp_output_format {
> + u32 bus_format;
> + u32 color_format;
> + u8 video_mapping;
> + u8 bpc;
> + u8 bpp;
> +};
> +
> +static const struct dw_dp_output_format dw_dp_output_formats[] = {
> + { MEDIA_BUS_FMT_RGB101010_1X30, DRM_COLOR_FORMAT_RGB444, DW_DP_RGB_10BIT, 10, 30 },
> + { MEDIA_BUS_FMT_RGB888_1X24, DRM_COLOR_FORMAT_RGB444, DW_DP_RGB_8BIT, 8, 24 },
> + { MEDIA_BUS_FMT_YUV10_1X30, DRM_COLOR_FORMAT_YCBCR444, DW_DP_YCBCR444_10BIT, 10, 30 },
> + { MEDIA_BUS_FMT_YUV8_1X24, DRM_COLOR_FORMAT_YCBCR444, DW_DP_YCBCR444_8BIT, 8, 24},
> + { MEDIA_BUS_FMT_YUYV10_1X20, DRM_COLOR_FORMAT_YCBCR422, DW_DP_YCBCR422_10BIT, 10, 20 },
> + { MEDIA_BUS_FMT_YUYV8_1X16, DRM_COLOR_FORMAT_YCBCR422, DW_DP_YCBCR422_8BIT, 8, 16 },
> + { MEDIA_BUS_FMT_UYYVYY10_0_5X30, DRM_COLOR_FORMAT_YCBCR420, DW_DP_YCBCR420_10BIT, 10, 15 },
> + { MEDIA_BUS_FMT_UYYVYY8_0_5X24, DRM_COLOR_FORMAT_YCBCR420, DW_DP_YCBCR420_8BIT, 8, 12 },
> + { MEDIA_BUS_FMT_RGB666_1X24_CPADHI, DRM_COLOR_FORMAT_RGB444, DW_DP_RGB_6BIT, 6, 18 },
> +};
> +
> +static const struct dw_dp_output_format *dw_dp_get_output_format(u32 bus_format)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < ARRAY_SIZE(dw_dp_output_formats); i++)
> + if (dw_dp_output_formats[i].bus_format == bus_format)
> + return &dw_dp_output_formats[i];
> +
> + return &dw_dp_output_formats[1];
Why? Shouldn't it be NULL?
> +}
> +
> +static inline struct dw_dp *bridge_to_dp(struct drm_bridge *b)
> +{
> + return container_of(b, struct dw_dp, bridge);
> +}
> +
> +static inline void dw_dp_phy_set_pattern(struct dw_dp *dp, u32 pattern)
> +{
> + regmap_update_bits(dp->regmap, DW_DP_PHYIF_CTRL, TPS_SEL,
> + FIELD_PREP(TPS_SEL, pattern));
> +}
> +
> +static void dw_dp_phy_xmit_enable(struct dw_dp *dp, u32 lanes)
> +{
> + u32 xmit_enable;
> +
> + switch (lanes) {
> + case 4:
> + case 2:
> + case 1:
> + xmit_enable = GENMASK(lanes - 1, 0);
> + break;
> + case 0:
> + default:
> + xmit_enable = 0;
> + break;
> + }
> +
> + regmap_update_bits(dp->regmap, DW_DP_PHYIF_CTRL, XMIT_ENABLE,
> + FIELD_PREP(XMIT_ENABLE, xmit_enable));
> +}
> +
> +static bool dw_dp_bandwidth_ok(struct dw_dp *dp,
> + const struct drm_display_mode *mode, u32 bpp,
> + unsigned int lanes, unsigned int rate)
> +{
> + u32 max_bw, req_bw;
> +
> + req_bw = mode->clock * bpp / 8;
> + max_bw = lanes * rate;
> + if (req_bw > max_bw)
> + return false;
> +
> + return true;
> +}
> +
> +static bool dw_dp_hpd_detect(struct dw_dp *dp)
> +{
> + u32 value;
> +
> + regmap_read(dp->regmap, DW_DP_HPD_STATUS, &value);
> +
> + return FIELD_GET(HPD_STATE, value) == DW_DP_HPD_STATE_PLUG;
> +}
> +
> +static void dw_dp_link_caps_reset(struct dw_dp_link_caps *caps)
> +{
> + caps->enhanced_framing = false;
> + caps->tps3_supported = false;
> + caps->tps4_supported = false;
> + caps->fast_training = false;
> + caps->channel_coding = false;
> +}
> +
> +static void dw_dp_link_reset(struct dw_dp_link *link)
> +{
> + link->vsc_sdp_supported = 0;
> + link->sink_count = 0;
> + link->revision = 0;
> + link->rate = 0;
> + link->lanes = 0;
> +
> + dw_dp_link_caps_reset(&link->caps);
> + memset(link->dpcd, 0, sizeof(link->dpcd));
> +}
> +
> +static int dw_dp_link_power_up(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + int ret;
> + u8 value;
> +
> + if (link->revision < DP_DPCD_REV_11)
> + return 0;
> +
> + ret = drm_dp_dpcd_readb(&dp->aux, DP_SET_POWER, &value);
> + if (ret < 0)
> + return ret;
> +
> + value &= ~DP_SET_POWER_MASK;
> + value |= DP_SET_POWER_D0;
> +
> + ret = drm_dp_dpcd_writeb(&dp->aux, DP_SET_POWER, value);
> + if (ret < 0)
> + return ret;
> +
> + usleep_range(1000, 2000);
> +
> + return 0;
> +}
> +
> +static int dw_dp_link_power_down(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + int ret;
> + u8 value;
> +
> + if (link->revision < DP_DPCD_REV_11)
> + return 0;
> +
> + ret = drm_dp_dpcd_readb(&dp->aux, DP_SET_POWER, &value);
> + if (ret < 0)
> + return ret;
> +
> + value &= ~DP_SET_POWER_MASK;
> + value |= DP_SET_POWER_D3;
> +
> + ret = drm_dp_dpcd_writeb(&dp->aux, DP_SET_POWER, value);
> + if (ret < 0)
> + return ret;
> +
Would you please mind pulling these two functions to DRM DP helpers?
There are enough users to make this into a common code.
> + return 0;
> +}
> +
> +static bool dw_dp_has_sink_count(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
> + const struct drm_dp_desc *desc)
> +{
> + return dpcd[DP_DPCD_REV] >= DP_DPCD_REV_11 &&
> + dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT &&
> + !drm_dp_has_quirk(desc, DP_DPCD_QUIRK_NO_SINK_COUNT);
isn't it drm_dp_read_sink_count_cap() ?
> +}
> +
> +static int dw_dp_link_parse(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + u8 dpcd;
> + int ret;
> +
> + dw_dp_link_reset(link);
> +
> + ret = drm_dp_read_dpcd_caps(&dp->aux, link->dpcd);
> + if (ret < 0)
> + return ret;
> +
> + drm_dp_read_desc(&dp->aux, &link->desc, drm_dp_is_branch(link->dpcd));
> +
> + if (dw_dp_has_sink_count(link->dpcd, &link->desc)) {
> + ret = drm_dp_read_sink_count(&dp->aux);
> + if (ret < 0)
> + return ret;
> +
> + link->sink_count = ret;
> +
> + /* Dongle connected, but no display */
> + if (!link->sink_count)
> + return -ENODEV;
> + }
> +
> + ret = drm_dp_dpcd_readb(&dp->aux, DP_DPRX_FEATURE_ENUMERATION_LIST, &dpcd);
> + if (ret < 0)
> + return ret;
> +
> + link->vsc_sdp_supported = !!(dpcd & DP_VSC_SDP_EXT_FOR_COLORIMETRY_SUPPORTED);
> +
> + link->revision = link->dpcd[DP_DPCD_REV];
> + link->rate = min_t(u32, min(dp->plat_data->max_link_rate,
> + dp->phy->attrs.max_link_rate * 100),
> + drm_dp_max_link_rate(link->dpcd));
> + link->lanes = min_t(u8, phy_get_bus_width(dp->phy),
> + drm_dp_max_lane_count(link->dpcd));
> +
> + link->caps.enhanced_framing = drm_dp_enhanced_frame_cap(link->dpcd);
> + link->caps.tps3_supported = drm_dp_tps3_supported(link->dpcd);
> + link->caps.tps4_supported = drm_dp_tps4_supported(link->dpcd);
> + link->caps.fast_training = drm_dp_fast_training_cap(link->dpcd);
> + link->caps.channel_coding = drm_dp_channel_coding_supported(link->dpcd);
> + link->caps.ssc = !!(link->dpcd[DP_MAX_DOWNSPREAD] & DP_MAX_DOWNSPREAD_0_5);
> +
> + return 0;
> +}
> +
> +static int dw_dp_phy_update_vs_emph(struct dw_dp *dp, unsigned int rate, unsigned int lanes,
> + struct dw_dp_link_train_set *train_set)
> +{
> + union phy_configure_opts phy_cfg;
> + unsigned int *vs, *pe;
> + u8 buf[4];
> + int i, ret;
> +
> + vs = train_set->voltage_swing;
> + pe = train_set->pre_emphasis;
> +
> + for (i = 0; i < lanes; i++) {
> + phy_cfg.dp.voltage[i] = vs[i];
> + phy_cfg.dp.pre[i] = pe[i];
> + }
> +
> + phy_cfg.dp.lanes = lanes;
> + phy_cfg.dp.link_rate = rate / 100;
> + phy_cfg.dp.set_lanes = false;
> + phy_cfg.dp.set_rate = false;
You don't need to set lanes / link_rate if set_lanes and set_rate is
false.
> + phy_cfg.dp.set_voltages = true;
> +
> + ret = phy_configure(dp->phy, &phy_cfg);
> + if (ret)
> + return ret;
> +
> + for (i = 0; i < lanes; i++) {
> + buf[i] = (vs[i] << DP_TRAIN_VOLTAGE_SWING_SHIFT) |
> + (pe[i] << DP_TRAIN_PRE_EMPHASIS_SHIFT);
> + if (train_set->voltage_max_reached[i])
> + buf[i] |= DP_TRAIN_MAX_SWING_REACHED;
> + if (train_set->pre_max_reached[i])
> + buf[i] |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
> + }
> +
> + ret = drm_dp_dpcd_write(&dp->aux, DP_TRAINING_LANE0_SET, buf, lanes);
> + if (ret < 0)
> + return ret;
> +
> + return 0;
> +}
> +
> +static int dw_dp_link_train_update_vs_emph(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + struct dw_dp_link_train_set *request = &link->train.request;
> +
> + return dw_dp_phy_update_vs_emph(dp, dp->link.rate, dp->link.lanes, request);
Inline it mayeb?
> +}
> +
> +static int dw_dp_phy_configure(struct dw_dp *dp, unsigned int rate,
> + unsigned int lanes, bool ssc)
> +{
> + union phy_configure_opts phy_cfg;
> + int ret;
> +
> + /* Move PHY to P3 */
> + regmap_update_bits(dp->regmap, DW_DP_PHYIF_CTRL, PHY_POWERDOWN,
> + FIELD_PREP(PHY_POWERDOWN, 0x3));
> +
> + phy_cfg.dp.lanes = lanes;
> + phy_cfg.dp.link_rate = rate / 100;
> + phy_cfg.dp.ssc = ssc;
> + phy_cfg.dp.set_lanes = true;
> + phy_cfg.dp.set_rate = true;
> + phy_cfg.dp.set_voltages = false;
> + ret = phy_configure(dp->phy, &phy_cfg);
> + if (ret)
> + return ret;
> +
> + regmap_update_bits(dp->regmap, DW_DP_PHYIF_CTRL, PHY_LANES,
> + FIELD_PREP(PHY_LANES, lanes / 2));
> +
> + /* Move PHY to P0 */
> + regmap_update_bits(dp->regmap, DW_DP_PHYIF_CTRL, PHY_POWERDOWN,
> + FIELD_PREP(PHY_POWERDOWN, 0x0));
> +
> + dw_dp_phy_xmit_enable(dp, lanes);
> +
> + return 0;
> +}
> +
> +static int dw_dp_link_configure(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + u8 buf[2];
> + int ret;
> +
> + ret = dw_dp_phy_configure(dp, link->rate, link->lanes, link->caps.ssc);
> + if (ret)
> + return ret;
> +
> + buf[0] = drm_dp_link_rate_to_bw_code(link->rate);
> + buf[1] = link->lanes;
> +
> + if (link->caps.enhanced_framing) {
> + buf[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
> + regmap_update_bits(dp->regmap, DW_DP_CCTL, ENHANCE_FRAMING_EN,
> + FIELD_PREP(ENHANCE_FRAMING_EN, 1));
> + } else {
> + regmap_update_bits(dp->regmap, DW_DP_CCTL, ENHANCE_FRAMING_EN,
> + FIELD_PREP(ENHANCE_FRAMING_EN, 0));
> + }
> +
> + ret = drm_dp_dpcd_write(&dp->aux, DP_LINK_BW_SET, buf, sizeof(buf));
> + if (ret < 0)
> + return ret;
> +
> + buf[0] = link->caps.ssc ? DP_SPREAD_AMP_0_5 : 0;
> + buf[1] = link->caps.channel_coding ? DP_SET_ANSI_8B10B : 0;
> +
> + ret = drm_dp_dpcd_write(&dp->aux, DP_DOWNSPREAD_CTRL, buf, sizeof(buf));
> + if (ret < 0)
> + return ret;
> +
> + return 0;
> +}
> +
> +static void dw_dp_link_train_init(struct dw_dp_link_train *train)
> +{
> + struct dw_dp_link_train_set *request = &train->request;
> + struct dw_dp_link_train_set *adjust = &train->adjust;
> + unsigned int i;
> +
> + for (i = 0; i < 4; i++) {
> + request->voltage_swing[i] = 0;
> + adjust->voltage_swing[i] = 0;
> +
> + request->pre_emphasis[i] = 0;
> + adjust->pre_emphasis[i] = 0;
> +
> + request->voltage_max_reached[i] = false;
> + adjust->voltage_max_reached[i] = false;
> +
> + request->pre_max_reached[i] = false;
> + adjust->pre_max_reached[i] = false;
> + }
> +
> + train->clock_recovered = false;
> + train->channel_equalized = false;
> +}
> +
> +static bool dw_dp_link_train_valid(const struct dw_dp_link_train *train)
> +{
> + return train->clock_recovered && train->channel_equalized;
> +}
> +
> +static int dw_dp_link_train_set_pattern(struct dw_dp *dp, u32 pattern)
> +{
> + u8 buf = 0;
> + int ret;
> +
> + if (pattern && pattern != DP_TRAINING_PATTERN_4) {
> + buf |= DP_LINK_SCRAMBLING_DISABLE;
> +
> + regmap_update_bits(dp->regmap, DW_DP_CCTL, SCRAMBLE_DIS,
> + FIELD_PREP(SCRAMBLE_DIS, 1));
> + } else {
> + regmap_update_bits(dp->regmap, DW_DP_CCTL, SCRAMBLE_DIS,
> + FIELD_PREP(SCRAMBLE_DIS, 0));
> + }
> +
> + switch (pattern) {
> + case DP_TRAINING_PATTERN_DISABLE:
> + dw_dp_phy_set_pattern(dp, DW_DP_PHY_PATTERN_NONE);
> + break;
> + case DP_TRAINING_PATTERN_1:
> + dw_dp_phy_set_pattern(dp, DW_DP_PHY_PATTERN_TPS_1);
> + break;
> + case DP_TRAINING_PATTERN_2:
> + dw_dp_phy_set_pattern(dp, DW_DP_PHY_PATTERN_TPS_2);
> + break;
> + case DP_TRAINING_PATTERN_3:
> + dw_dp_phy_set_pattern(dp, DW_DP_PHY_PATTERN_TPS_3);
> + break;
> + case DP_TRAINING_PATTERN_4:
> + dw_dp_phy_set_pattern(dp, DW_DP_PHY_PATTERN_TPS_4);
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + ret = drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,
> + buf | pattern);
> + if (ret < 0)
> + return ret;
> +
> + return 0;
> +}
> +
> +static u8 dw_dp_voltage_max(u8 preemph)
> +{
> + switch (preemph & DP_TRAIN_PRE_EMPHASIS_MASK) {
> + case DP_TRAIN_PRE_EMPH_LEVEL_0:
> + return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
> + case DP_TRAIN_PRE_EMPH_LEVEL_1:
> + return DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
> + case DP_TRAIN_PRE_EMPH_LEVEL_2:
> + return DP_TRAIN_VOLTAGE_SWING_LEVEL_1;
> + case DP_TRAIN_PRE_EMPH_LEVEL_3:
> + default:
> + return DP_TRAIN_VOLTAGE_SWING_LEVEL_0;
> + }
> +}
> +
> +static void dw_dp_link_get_adjustments(struct dw_dp_link *link,
> + u8 status[DP_LINK_STATUS_SIZE])
> +{
> + struct dw_dp_link_train_set *adjust = &link->train.adjust;
> + u8 v = 0;
> + u8 p = 0;
> + unsigned int i;
> +
> + for (i = 0; i < link->lanes; i++) {
> + v = drm_dp_get_adjust_request_voltage(status, i);
> + p = drm_dp_get_adjust_request_pre_emphasis(status, i);
> + if (p >= DP_TRAIN_PRE_EMPH_LEVEL_3) {
> + adjust->pre_emphasis[i] = DP_TRAIN_PRE_EMPH_LEVEL_3 >>
> + DP_TRAIN_PRE_EMPHASIS_SHIFT;
> + adjust->pre_max_reached[i] = true;
> + } else {
> + adjust->pre_emphasis[i] = p >> DP_TRAIN_PRE_EMPHASIS_SHIFT;
> + adjust->pre_max_reached[i] = false;
> + }
> + v = min(v, dw_dp_voltage_max(p));
> + if (v >= DP_TRAIN_VOLTAGE_SWING_LEVEL_3) {
> + adjust->voltage_swing[i] = DP_TRAIN_VOLTAGE_SWING_LEVEL_3 >>
> + DP_TRAIN_VOLTAGE_SWING_SHIFT;
> + adjust->voltage_max_reached[i] = true;
> + } else {
> + adjust->voltage_swing[i] = v >> DP_TRAIN_VOLTAGE_SWING_SHIFT;
> + adjust->voltage_max_reached[i] = false;
> + }
> + }
> +}
> +
> +static void dw_dp_link_train_adjust(struct dw_dp_link_train *train)
> +{
> + struct dw_dp_link_train_set *request = &train->request;
> + struct dw_dp_link_train_set *adjust = &train->adjust;
> + unsigned int i;
> +
> + for (i = 0; i < 4; i++) {
Shouldn't it be a loop up to link->lanes?
> + if (request->voltage_swing[i] != adjust->voltage_swing[i])
> + request->voltage_swing[i] = adjust->voltage_swing[i];
> + if (request->voltage_max_reached[i] != adjust->voltage_max_reached[i])
> + request->voltage_max_reached[i] = adjust->voltage_max_reached[i];
> + }
> +
> + for (i = 0; i < 4; i++) {
> + if (request->pre_emphasis[i] != adjust->pre_emphasis[i])
> + request->pre_emphasis[i] = adjust->pre_emphasis[i];
> + if (request->pre_max_reached[i] != adjust->pre_max_reached[i])
> + request->pre_max_reached[i] = adjust->pre_max_reached[i];
Why do you need separate request and adjustment structs?
> + }
> +}
> +
> +static int dw_dp_link_clock_recovery(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + u8 status[DP_LINK_STATUS_SIZE];
> + unsigned int tries = 0;
> + int ret;
> +
> + ret = dw_dp_link_train_set_pattern(dp, DP_TRAINING_PATTERN_1);
> + if (ret)
> + return ret;
> +
> + for (;;) {
> + ret = dw_dp_link_train_update_vs_emph(dp);
> + if (ret)
> + return ret;
> +
> + drm_dp_link_train_clock_recovery_delay(&dp->aux, link->dpcd);
> +
> + ret = drm_dp_dpcd_read_link_status(&dp->aux, status);
> + if (ret < 0) {
> + dev_err(dp->dev, "failed to read link status: %d\n", ret);
> + return ret;
> + }
> +
> + if (drm_dp_clock_recovery_ok(status, link->lanes)) {
> + link->train.clock_recovered = true;
> + break;
> + }
> +
> + dw_dp_link_get_adjustments(link, status);
> +
> + if (link->train.request.voltage_swing[0] ==
> + link->train.adjust.voltage_swing[0])
Should this take all lanes to account? I think it might be posssible to
drop the adjust / request split and adjust tries in
dw_dp_link_get_adjustments() instead.
> + tries++;
> + else
> + tries = 0;
> +
> + if (tries == 5)
> + break;
> +
> + dw_dp_link_train_adjust(&link->train);
> + }
> +
> + return 0;
> +}
> +
> +static int dw_dp_link_channel_equalization(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + u8 status[DP_LINK_STATUS_SIZE], pattern;
> + unsigned int tries;
> + int ret;
> +
> + if (link->caps.tps4_supported)
> + pattern = DP_TRAINING_PATTERN_4;
> + else if (link->caps.tps3_supported)
> + pattern = DP_TRAINING_PATTERN_3;
> + else
> + pattern = DP_TRAINING_PATTERN_2;
> + ret = dw_dp_link_train_set_pattern(dp, pattern);
> + if (ret)
> + return ret;
> +
> + for (tries = 1; tries < 5; tries++) {
> + ret = dw_dp_link_train_update_vs_emph(dp);
> + if (ret)
> + return ret;
> +
> + drm_dp_link_train_channel_eq_delay(&dp->aux, link->dpcd);
> +
> + ret = drm_dp_dpcd_read_link_status(&dp->aux, status);
> + if (ret < 0)
> + return ret;
> +
> + if (!drm_dp_clock_recovery_ok(status, link->lanes)) {
> + dev_err(dp->dev, "clock recovery lost while equalizing channel\n");
> + link->train.clock_recovered = false;
> + break;
> + }
> +
> + if (drm_dp_channel_eq_ok(status, link->lanes)) {
> + link->train.channel_equalized = true;
> + break;
> + }
> +
> + dw_dp_link_get_adjustments(link, status);
> + dw_dp_link_train_adjust(&link->train);
> + }
> +
> + return 0;
> +}
> +
> +static int dw_dp_link_downgrade(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + struct dw_dp_video *video = &dp->video;
> +
> + switch (link->rate) {
> + case 162000:
> + return -EINVAL;
> + case 270000:
> + link->rate = 162000;
> + break;
> + case 540000:
> + link->rate = 270000;
> + break;
> + case 810000:
> + link->rate = 540000;
> + break;
> + }
> +
> + if (!dw_dp_bandwidth_ok(dp, &video->mode, video->bpp, link->lanes,
> + link->rate))
> + return -E2BIG;
> +
> + return 0;
> +}
> +
> +static int dw_dp_link_train_full(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + int ret;
> +
> +retry:
> + dw_dp_link_train_init(&link->train);
> +
> + dev_dbg(dp->dev, "full-training link: %u lane%s at %u MHz\n",
> + link->lanes, (link->lanes > 1) ? "s" : "", link->rate / 100);
> +
> + ret = dw_dp_link_configure(dp);
> + if (ret < 0) {
> + dev_err(dp->dev, "failed to configure DP link: %d\n", ret);
> + return ret;
> + }
> +
> + ret = dw_dp_link_clock_recovery(dp);
> + if (ret < 0) {
> + dev_err(dp->dev, "clock recovery failed: %d\n", ret);
> + goto out;
> + }
> +
> + if (!link->train.clock_recovered) {
> + dev_err(dp->dev, "clock recovery failed, downgrading link\n");
> +
> + ret = dw_dp_link_downgrade(dp);
> + if (ret < 0)
> + goto out;
> + else
> + goto retry;
> + }
> +
> + dev_dbg(dp->dev, "clock recovery succeeded\n");
> +
> + ret = dw_dp_link_channel_equalization(dp);
> + if (ret < 0) {
> + dev_err(dp->dev, "channel equalization failed: %d\n", ret);
> + goto out;
> + }
> +
> + if (!link->train.channel_equalized) {
> + dev_err(dp->dev, "channel equalization failed, downgrading link\n");
> +
> + ret = dw_dp_link_downgrade(dp);
> + if (ret < 0)
> + goto out;
> + else
> + goto retry;
> + }
> +
> + dev_dbg(dp->dev, "channel equalization succeeded\n");
> +
> +out:
> + dw_dp_link_train_set_pattern(dp, DP_TRAINING_PATTERN_DISABLE);
> + return ret;
> +}
> +
> +static int dw_dp_link_train_fast(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + int ret;
> + u8 status[DP_LINK_STATUS_SIZE];
> + u8 pattern;
> +
> + dw_dp_link_train_init(&link->train);
> +
> + dev_dbg(dp->dev, "fast-training link: %u lane%s at %u MHz\n",
> + link->lanes, (link->lanes > 1) ? "s" : "", link->rate / 100);
> +
> + ret = dw_dp_link_configure(dp);
> + if (ret < 0) {
> + dev_err(dp->dev, "failed to configure DP link: %d\n", ret);
> + return ret;
> + }
> +
> + ret = dw_dp_link_train_set_pattern(dp, DP_TRAINING_PATTERN_1);
> + if (ret)
> + goto out;
> +
> + usleep_range(500, 1000);
> +
> + if (link->caps.tps4_supported)
> + pattern = DP_TRAINING_PATTERN_4;
> + else if (link->caps.tps3_supported)
> + pattern = DP_TRAINING_PATTERN_3;
> + else
> + pattern = DP_TRAINING_PATTERN_2;
> + ret = dw_dp_link_train_set_pattern(dp, pattern);
> + if (ret)
> + goto out;
> +
> + usleep_range(500, 1000);
> +
> + ret = drm_dp_dpcd_read_link_status(&dp->aux, status);
> + if (ret < 0) {
> + dev_err(dp->dev, "failed to read link status: %d\n", ret);
> + goto out;
> + }
> +
> + if (!drm_dp_clock_recovery_ok(status, link->lanes)) {
> + dev_err(dp->dev, "clock recovery failed\n");
> + ret = -EIO;
> + goto out;
> + }
> +
> + if (!drm_dp_channel_eq_ok(status, link->lanes)) {
> + dev_err(dp->dev, "channel equalization failed\n");
> + ret = -EIO;
> + goto out;
> + }
> +
> +out:
> + dw_dp_link_train_set_pattern(dp, DP_TRAINING_PATTERN_DISABLE);
> + return ret;
> +}
> +
> +static int dw_dp_link_train(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + int ret;
> +
> + if (link->caps.fast_training) {
> + if (dw_dp_link_train_valid(&link->train)) {
> + ret = dw_dp_link_train_fast(dp);
> + if (ret < 0)
> + dev_err(dp->dev, "fast link training failed: %d\n", ret);
> + else
> + return 0;
> + }
> + }
> +
> + ret = dw_dp_link_train_full(dp);
> + if (ret < 0) {
> + dev_err(dp->dev, "full link training failed: %d\n", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int dw_dp_send_sdp(struct dw_dp *dp, struct dw_dp_sdp *sdp)
> +{
> + const u8 *payload = sdp->db;
> + u32 reg;
> + int i, nr;
> +
> + nr = find_first_zero_bit(dp->sdp_reg_bank, SDP_REG_BANK_SIZE);
> + if (nr < SDP_REG_BANK_SIZE)
> + set_bit(nr, dp->sdp_reg_bank);
> + else
> + return -EBUSY;
> +
> + reg = DW_DP_SDP_REGISTER_BANK + nr * 9 * 4;
> +
> + /* SDP header */
> + regmap_write(dp->regmap, reg, get_unaligned_le32(&sdp->header));
> +
> + /* SDP data payload */
> + for (i = 1; i < 9; i++, payload += 4)
> + regmap_write(dp->regmap, reg + i * 4,
> + FIELD_PREP(SDP_REGS, get_unaligned_le32(payload)));
> +
> + if (sdp->flags & DW_DP_SDP_VERTICAL_INTERVAL)
> + regmap_update_bits(dp->regmap, DW_DP_SDP_VERTICAL_CTRL,
> + EN_VERTICAL_SDP << nr,
> + EN_VERTICAL_SDP << nr);
> +
> + if (sdp->flags & DW_DP_SDP_HORIZONTAL_INTERVAL)
> + regmap_update_bits(dp->regmap, DW_DP_SDP_HORIZONTAL_CTRL,
> + EN_HORIZONTAL_SDP << nr,
> + EN_HORIZONTAL_SDP << nr);
> +
> + return 0;
> +}
> +
> +static void dw_dp_vsc_sdp_pack(const struct drm_dp_vsc_sdp *vsc,
> + struct dw_dp_sdp *sdp)
Use drm_dp_vsc_sdp_pack() instead.
> +{
> + sdp->header.HB0 = 0;
> + sdp->header.HB1 = DP_SDP_VSC;
> + sdp->header.HB2 = vsc->revision;
> + sdp->header.HB3 = vsc->length;
> +
> + sdp->db[16] = (vsc->pixelformat & 0xf) << 4;
> + sdp->db[16] |= vsc->colorimetry & 0xf;
> +
> + switch (vsc->bpc) {
> + case 8:
> + sdp->db[17] = 0x1;
> + break;
> + case 10:
> + sdp->db[17] = 0x2;
> + break;
> + case 12:
> + sdp->db[17] = 0x3;
> + break;
> + case 16:
> + sdp->db[17] = 0x4;
> + break;
> + case 6:
> + default:
> + break;
> + }
> +
> + if (vsc->dynamic_range == DP_DYNAMIC_RANGE_CTA)
> + sdp->db[17] |= 0x80;
> +
> + sdp->db[18] = vsc->content_type & 0x7;
> +
> + sdp->flags |= DW_DP_SDP_VERTICAL_INTERVAL;
> +}
> +
> +static int dw_dp_send_vsc_sdp(struct dw_dp *dp)
> +{
> + struct dw_dp_video *video = &dp->video;
> + struct drm_dp_vsc_sdp vsc = {};
> + struct dw_dp_sdp sdp = {};
> +
> + vsc.revision = 0x5;
> + vsc.length = 0x13;
> +
> + switch (video->color_format) {
> + case DRM_COLOR_FORMAT_YCBCR444:
> + vsc.pixelformat = DP_PIXELFORMAT_YUV444;
> + break;
> + case DRM_COLOR_FORMAT_YCBCR420:
> + vsc.pixelformat = DP_PIXELFORMAT_YUV420;
> + break;
> + case DRM_COLOR_FORMAT_YCBCR422:
> + vsc.pixelformat = DP_PIXELFORMAT_YUV422;
> + break;
> + case DRM_COLOR_FORMAT_RGB444:
> + default:
> + vsc.pixelformat = DP_PIXELFORMAT_RGB;
> + break;
> + }
> +
> + if (video->color_format == DRM_COLOR_FORMAT_RGB444) {
> + vsc.colorimetry = DP_COLORIMETRY_DEFAULT;
> + vsc.dynamic_range = DP_DYNAMIC_RANGE_VESA;
> + } else {
> + vsc.colorimetry = DP_COLORIMETRY_BT709_YCC;
> + vsc.dynamic_range = DP_DYNAMIC_RANGE_CTA;
> + }
> +
> + vsc.bpc = video->bpc;
> + vsc.content_type = DP_CONTENT_TYPE_NOT_DEFINED;
> +
> + dw_dp_vsc_sdp_pack(&vsc, &sdp);
> +
> + return dw_dp_send_sdp(dp, &sdp);
> +}
> +
> +static int dw_dp_video_set_pixel_mode(struct dw_dp *dp, u8 pixel_mode)
> +{
> + switch (pixel_mode) {
> + case DW_DP_MP_SINGLE_PIXEL:
> + case DW_DP_MP_DUAL_PIXEL:
> + case DW_DP_MP_QUAD_PIXEL:
> + break;
> + default:
> + return -EINVAL;
Is it possible?
> + }
> +
> + regmap_update_bits(dp->regmap, DW_DP_VSAMPLE_CTRL, PIXEL_MODE_SELECT,
> + FIELD_PREP(PIXEL_MODE_SELECT, pixel_mode));
> +
> + return 0;
> +}
> +
> +static bool dw_dp_video_need_vsc_sdp(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + struct dw_dp_video *video = &dp->video;
> +
> + if (!link->vsc_sdp_supported)
> + return false;
> +
> + if (video->color_format == DRM_COLOR_FORMAT_YCBCR420)
> + return true;
> +
> + return false;
> +}
> +
> +static int dw_dp_video_set_msa(struct dw_dp *dp, u8 color_format, u8 bpc,
> + u16 vstart, u16 hstart)
> +{
> + u16 misc = 0;
> +
> + if (dw_dp_video_need_vsc_sdp(dp))
> + misc |= DP_MSA_MISC_COLOR_VSC_SDP;
> +
> + switch (color_format) {
> + case DRM_COLOR_FORMAT_RGB444:
> + misc |= DP_MSA_MISC_COLOR_RGB;
> + break;
> + case DRM_COLOR_FORMAT_YCBCR444:
> + misc |= DP_MSA_MISC_COLOR_YCBCR_444_BT709;
> + break;
> + case DRM_COLOR_FORMAT_YCBCR422:
> + misc |= DP_MSA_MISC_COLOR_YCBCR_422_BT709;
> + break;
> + case DRM_COLOR_FORMAT_YCBCR420:
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + switch (bpc) {
> + case 6:
> + misc |= DP_MSA_MISC_6_BPC;
> + break;
> + case 8:
> + misc |= DP_MSA_MISC_8_BPC;
> + break;
> + case 10:
> + misc |= DP_MSA_MISC_10_BPC;
> + break;
> + case 12:
> + misc |= DP_MSA_MISC_12_BPC;
> + break;
> + case 16:
> + misc |= DP_MSA_MISC_16_BPC;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + regmap_write(dp->regmap, DW_DP_VIDEO_MSA1,
> + FIELD_PREP(VSTART, vstart) | FIELD_PREP(HSTART, hstart));
> + regmap_write(dp->regmap, DW_DP_VIDEO_MSA2, FIELD_PREP(MISC0, misc));
> + regmap_write(dp->regmap, DW_DP_VIDEO_MSA3, FIELD_PREP(MISC1, misc >> 8));
> +
> + return 0;
> +}
> +
> +static void dw_dp_video_disable(struct dw_dp *dp)
> +{
> + regmap_update_bits(dp->regmap, DW_DP_VSAMPLE_CTRL, VIDEO_STREAM_ENABLE,
> + FIELD_PREP(VIDEO_STREAM_ENABLE, 0));
> +}
> +
> +static int dw_dp_video_enable(struct dw_dp *dp)
> +{
> + struct dw_dp_video *video = &dp->video;
> + struct dw_dp_link *link = &dp->link;
> + struct drm_display_mode *mode = &video->mode;
> + u8 color_format = video->color_format;
> + u8 bpc = video->bpc;
> + u8 pixel_mode = video->pixel_mode;
> + u8 bpp = video->bpp, init_threshold, vic;
> + u32 hactive, hblank, h_sync_width, h_front_porch;
> + u32 vactive, vblank, v_sync_width, v_front_porch;
> + u32 vstart = mode->vtotal - mode->vsync_start;
> + u32 hstart = mode->htotal - mode->hsync_start;
> + u32 peak_stream_bandwidth, link_bandwidth;
> + u32 average_bytes_per_tu, average_bytes_per_tu_frac;
> + u32 ts, hblank_interval;
> + u32 value;
> + int ret;
> +
> + ret = dw_dp_video_set_pixel_mode(dp, pixel_mode);
> + if (ret)
> + return ret;
> +
> + ret = dw_dp_video_set_msa(dp, color_format, bpc, vstart, hstart);
> + if (ret)
> + return ret;
> +
> + regmap_update_bits(dp->regmap, DW_DP_VSAMPLE_CTRL, VIDEO_MAPPING,
> + FIELD_PREP(VIDEO_MAPPING, video->video_mapping));
> +
> + /* Configure DW_DP_VINPUT_POLARITY_CTRL register */
> + value = 0;
> + if (mode->flags & DRM_MODE_FLAG_PHSYNC)
> + value |= FIELD_PREP(HSYNC_IN_POLARITY, 1);
> + if (mode->flags & DRM_MODE_FLAG_PVSYNC)
> + value |= FIELD_PREP(VSYNC_IN_POLARITY, 1);
> + regmap_write(dp->regmap, DW_DP_VINPUT_POLARITY_CTRL, value);
> +
> + /* Configure DW_DP_VIDEO_CONFIG1 register */
> + hactive = mode->hdisplay;
> + hblank = mode->htotal - mode->hdisplay;
> + value = FIELD_PREP(HACTIVE, hactive) | FIELD_PREP(HBLANK, hblank);
> + if (mode->flags & DRM_MODE_FLAG_INTERLACE)
> + value |= FIELD_PREP(I_P, 1);
> + vic = drm_match_cea_mode(mode);
> + if (vic == 5 || vic == 6 || vic == 7 ||
> + vic == 10 || vic == 11 || vic == 20 ||
> + vic == 21 || vic == 22 || vic == 39 ||
> + vic == 25 || vic == 26 || vic == 40 ||
> + vic == 44 || vic == 45 || vic == 46 ||
> + vic == 50 || vic == 51 || vic == 54 ||
> + vic == 55 || vic == 58 || vic == 59)
> + value |= R_V_BLANK_IN_OSC;
> + regmap_write(dp->regmap, DW_DP_VIDEO_CONFIG1, value);
> +
> + /* Configure DW_DP_VIDEO_CONFIG2 register */
> + vblank = mode->vtotal - mode->vdisplay;
> + vactive = mode->vdisplay;
> + regmap_write(dp->regmap, DW_DP_VIDEO_CONFIG2,
> + FIELD_PREP(VBLANK, vblank) | FIELD_PREP(VACTIVE, vactive));
> +
> + /* Configure DW_DP_VIDEO_CONFIG3 register */
> + h_sync_width = mode->hsync_end - mode->hsync_start;
> + h_front_porch = mode->hsync_start - mode->hdisplay;
> + regmap_write(dp->regmap, DW_DP_VIDEO_CONFIG3,
> + FIELD_PREP(H_SYNC_WIDTH, h_sync_width) |
> + FIELD_PREP(H_FRONT_PORCH, h_front_porch));
> +
> + /* Configure DW_DP_VIDEO_CONFIG4 register */
> + v_sync_width = mode->vsync_end - mode->vsync_start;
> + v_front_porch = mode->vsync_start - mode->vdisplay;
> + regmap_write(dp->regmap, DW_DP_VIDEO_CONFIG4,
> + FIELD_PREP(V_SYNC_WIDTH, v_sync_width) |
> + FIELD_PREP(V_FRONT_PORCH, v_front_porch));
> +
> + /* Configure DW_DP_VIDEO_CONFIG5 register */
> + peak_stream_bandwidth = mode->clock * bpp / 8;
> + link_bandwidth = (link->rate / 1000) * link->lanes;
> + ts = peak_stream_bandwidth * 64 / link_bandwidth;
> + average_bytes_per_tu = ts / 1000;
> + average_bytes_per_tu_frac = ts / 100 - average_bytes_per_tu * 10;
> + if (pixel_mode == DW_DP_MP_SINGLE_PIXEL) {
> + if (average_bytes_per_tu < 6)
> + init_threshold = 32;
> + else if (hblank <= 80 && color_format != DRM_COLOR_FORMAT_YCBCR420)
> + init_threshold = 12;
> + else if (hblank <= 40 && color_format == DRM_COLOR_FORMAT_YCBCR420)
> + init_threshold = 3;
> + else
> + init_threshold = 16;
> + } else {
> + u32 t1 = 0, t2 = 0, t3 = 0;
> +
> + switch (bpc) {
> + case 6:
> + t1 = (4 * 1000 / 9) * link->lanes;
> + break;
> + case 8:
> + if (color_format == DRM_COLOR_FORMAT_YCBCR422) {
> + t1 = (1000 / 2) * link->lanes;
> + } else {
> + if (pixel_mode == DW_DP_MP_DUAL_PIXEL)
> + t1 = (1000 / 3) * link->lanes;
> + else
> + t1 = (3000 / 16) * link->lanes;
> + }
> + break;
> + case 10:
> + if (color_format == DRM_COLOR_FORMAT_YCBCR422)
> + t1 = (2000 / 5) * link->lanes;
> + else
> + t1 = (4000 / 15) * link->lanes;
> + break;
> + case 12:
> + if (color_format == DRM_COLOR_FORMAT_YCBCR422) {
> + if (pixel_mode == DW_DP_MP_DUAL_PIXEL)
> + t1 = (1000 / 6) * link->lanes;
> + else
> + t1 = (1000 / 3) * link->lanes;
> + } else {
> + t1 = (2000 / 9) * link->lanes;
> + }
> + break;
> + case 16:
> + if (color_format != DRM_COLOR_FORMAT_YCBCR422 &&
> + pixel_mode == DW_DP_MP_DUAL_PIXEL)
> + t1 = (1000 / 6) * link->lanes;
> + else
> + t1 = (1000 / 4) * link->lanes;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + if (color_format == DRM_COLOR_FORMAT_YCBCR420)
> + t2 = (link->rate / 4) * 1000 / (mode->clock / 2);
> + else
> + t2 = (link->rate / 4) * 1000 / mode->clock;
> +
> + if (average_bytes_per_tu_frac)
> + t3 = average_bytes_per_tu + 1;
> + else
> + t3 = average_bytes_per_tu;
> + init_threshold = t1 * t2 * t3 / (1000 * 1000);
> + if (init_threshold <= 16 || average_bytes_per_tu < 10)
> + init_threshold = 40;
> + }
> +
> + regmap_write(dp->regmap, DW_DP_VIDEO_CONFIG5,
> + FIELD_PREP(INIT_THRESHOLD_HI, init_threshold >> 6) |
> + FIELD_PREP(AVERAGE_BYTES_PER_TU_FRAC, average_bytes_per_tu_frac) |
> + FIELD_PREP(INIT_THRESHOLD, init_threshold) |
> + FIELD_PREP(AVERAGE_BYTES_PER_TU, average_bytes_per_tu));
> +
> + /* Configure DW_DP_VIDEO_HBLANK_INTERVAL register */
> + hblank_interval = hblank * (link->rate / 4) / mode->clock;
> + regmap_write(dp->regmap, DW_DP_VIDEO_HBLANK_INTERVAL,
> + FIELD_PREP(HBLANK_INTERVAL_EN, 1) |
> + FIELD_PREP(HBLANK_INTERVAL, hblank_interval));
> +
> + /* Video stream enable */
> + regmap_update_bits(dp->regmap, DW_DP_VSAMPLE_CTRL, VIDEO_STREAM_ENABLE,
> + FIELD_PREP(VIDEO_STREAM_ENABLE, 1));
> +
> + if (dw_dp_video_need_vsc_sdp(dp))
> + dw_dp_send_vsc_sdp(dp);
> +
> + return 0;
> +}
> +
> +static void dw_dp_hpd_init(struct dw_dp *dp)
> +{
> + /* Enable all HPD interrupts */
> + regmap_update_bits(dp->regmap, DW_DP_HPD_INTERRUPT_ENABLE,
> + HPD_UNPLUG_EN | HPD_PLUG_EN | HPD_IRQ_EN,
> + FIELD_PREP(HPD_UNPLUG_EN, 1) |
> + FIELD_PREP(HPD_PLUG_EN, 1) |
> + FIELD_PREP(HPD_IRQ_EN, 1));
> +
> + /* Enable all top-level interrupts */
> + regmap_update_bits(dp->regmap, DW_DP_GENERAL_INTERRUPT_ENABLE,
> + HPD_EVENT_EN, FIELD_PREP(HPD_EVENT_EN, 1));
> +}
> +
> +static void dw_dp_aux_init(struct dw_dp *dp)
> +{
> + regmap_update_bits(dp->regmap, DW_DP_GENERAL_INTERRUPT_ENABLE,
> + AUX_REPLY_EVENT_EN, FIELD_PREP(AUX_REPLY_EVENT_EN, 1));
> +}
> +
> +static void dw_dp_init_hw(struct dw_dp *dp)
> +{
> + regmap_update_bits(dp->regmap, DW_DP_CCTL, DEFAULT_FAST_LINK_TRAIN_EN,
> + FIELD_PREP(DEFAULT_FAST_LINK_TRAIN_EN, 0));
> +
> + dw_dp_hpd_init(dp);
> + dw_dp_aux_init(dp);
> +}
> +
> +static int dw_dp_aux_write_data(struct dw_dp *dp, const u8 *buffer, size_t size)
> +{
> + size_t i, j;
> +
> + for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
> + size_t num = min_t(size_t, size - i * 4, 4);
> + u32 value = 0;
> +
> + for (j = 0; j < num; j++)
> + value |= buffer[i * 4 + j] << (j * 8);
> +
> + regmap_write(dp->regmap, DW_DP_AUX_DATA0 + i * 4, value);
> + }
> +
> + return size;
> +}
> +
> +static int dw_dp_aux_read_data(struct dw_dp *dp, u8 *buffer, size_t size)
> +{
> + size_t i, j;
> +
> + for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
> + size_t num = min_t(size_t, size - i * 4, 4);
> + u32 value;
> +
> + regmap_read(dp->regmap, DW_DP_AUX_DATA0 + i * 4, &value);
> +
> + for (j = 0; j < num; j++)
> + buffer[i * 4 + j] = value >> (j * 8);
> + }
> +
> + return size;
> +}
> +
> +static ssize_t dw_dp_aux_transfer(struct drm_dp_aux *aux,
> + struct drm_dp_aux_msg *msg)
> +{
> + struct dw_dp *dp = container_of(aux, struct dw_dp, aux);
> + unsigned long timeout = msecs_to_jiffies(10);
> + u32 status, value;
> + ssize_t ret = 0;
> +
> + if (WARN_ON(msg->size > 16))
> + return -E2BIG;
> +
> + switch (msg->request & ~DP_AUX_I2C_MOT) {
> + case DP_AUX_NATIVE_WRITE:
> + case DP_AUX_I2C_WRITE:
> + case DP_AUX_I2C_WRITE_STATUS_UPDATE:
> + ret = dw_dp_aux_write_data(dp, msg->buffer, msg->size);
> + if (ret < 0)
> + return ret;
> + break;
> + case DP_AUX_NATIVE_READ:
> + case DP_AUX_I2C_READ:
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + if (msg->size > 0)
> + value = FIELD_PREP(AUX_LEN_REQ, msg->size - 1);
> + else
> + value = FIELD_PREP(I2C_ADDR_ONLY, 1);
> + value |= FIELD_PREP(AUX_CMD_TYPE, msg->request);
> + value |= FIELD_PREP(AUX_ADDR, msg->address);
> + regmap_write(dp->regmap, DW_DP_AUX_CMD, value);
> +
> + status = wait_for_completion_timeout(&dp->complete, timeout);
> + if (!status) {
> + dev_err(dp->dev, "timeout waiting for AUX reply\n");
> + return -ETIMEDOUT;
> + }
> +
> + regmap_read(dp->regmap, DW_DP_AUX_STATUS, &value);
> + if (value & AUX_TIMEOUT)
> + return -ETIMEDOUT;
> +
> + msg->reply = FIELD_GET(AUX_STATUS, value);
> +
> + if (msg->size > 0 && msg->reply == DP_AUX_NATIVE_REPLY_ACK) {
> + if (msg->request & DP_AUX_I2C_READ) {
> + size_t count = FIELD_GET(AUX_BYTES_READ, value) - 1;
> +
> + if (count != msg->size)
> + return -EBUSY;
> +
> + ret = dw_dp_aux_read_data(dp, msg->buffer, count);
> + if (ret < 0)
> + return ret;
> + }
> + }
> +
> + return ret;
> +}
> +
> +/*
> + * Limits for the video timing output by DP:
> + * 1. the hfp should be 2 pixels aligned;
> + * 2. the minimum hsync should be 9 pixel;
> + * 3. the minimum hbp should be 16 pixel;
> + */
> +static bool dw_dp_bridge_mode_fixup(struct drm_bridge *bridge,
> + const struct drm_display_mode *mode,
> + struct drm_display_mode *adjusted_mode)
> +{
> + struct dw_dp *dp = bridge_to_dp(bridge);
> + int min_hbp = 16;
> + int min_hsync = 9;
> +
> + if ((adjusted_mode->hsync_start - adjusted_mode->hdisplay) & 0x1) {
> + adjusted_mode->hsync_start += 1;
> + dev_warn(dp->dev, "hfp is not 2 pixeel aligned, fixup to aligned hfp\n");
> + }
> + if (adjusted_mode->hsync_end - adjusted_mode->hsync_start < min_hsync) {
> + adjusted_mode->hsync_end = adjusted_mode->hsync_start + min_hsync;
> + dev_warn(dp->dev, "hsync is too narrow, fixup to min hsync:%d\n", min_hsync);
> + }
> + if (adjusted_mode->htotal - adjusted_mode->hsync_end < min_hbp) {
> + adjusted_mode->htotal = adjusted_mode->hsync_end + min_hbp;
> + dev_warn(dp->dev, "hbp is too narrow, fixup to min hbp:%d\n", min_hbp);
> + }
> +
> + return true;
> +}
> +
> +static enum drm_mode_status dw_dp_bridge_mode_valid(struct drm_bridge *bridge,
> + const struct drm_display_info *info,
> + const struct drm_display_mode *mode)
> +{
> + struct dw_dp *dp = bridge_to_dp(bridge);
> + struct dw_dp_link *link = &dp->link;
> + u32 min_bpp;
> +
> + if (info->color_formats & DRM_COLOR_FORMAT_YCBCR420 &&
> + link->vsc_sdp_supported &&
> + (drm_mode_is_420_only(info, mode) || drm_mode_is_420_also(info, mode)))
> + min_bpp = 12;
> + else if (info->color_formats & DRM_COLOR_FORMAT_YCBCR422)
> + min_bpp = 16;
> + else if (info->color_formats & DRM_COLOR_FORMAT_RGB444)
> + min_bpp = 18;
> + else
> + min_bpp = 24;
> +
> + if (!link->vsc_sdp_supported &&
> + drm_mode_is_420_only(info, mode))
> + return MODE_NO_420;
> +
> + if (!dw_dp_bandwidth_ok(dp, mode, min_bpp, link->lanes, link->rate))
> + return MODE_CLOCK_HIGH;
> +
> + return MODE_OK;
> +}
> +
> +static void dw_dp_bridge_atomic_pre_enable(struct drm_bridge *bridge,
> + struct drm_bridge_state *old_bridge_state)
> +{
> + struct drm_atomic_state *state = old_bridge_state->base.state;
> + struct drm_crtc_state *crtc_state = bridge->encoder->crtc->state;
> + struct dw_dp *dp = bridge_to_dp(bridge);
> + struct dw_dp_video *video = &dp->video;
> + struct drm_display_mode *m = &video->mode;
> + struct drm_bridge_state *bridge_state;
> + const struct dw_dp_output_format *fmt;
> +
> + drm_mode_copy(m, &crtc_state->adjusted_mode);
> +
> + bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
> + fmt = dw_dp_get_output_format(bridge_state->output_bus_cfg.format);
Should it be a part of the atomic_check() instead?
> +
> + video->video_mapping = fmt->video_mapping;
> + video->color_format = fmt->color_format;
> + video->bpc = fmt->bpc;
> + video->bpp = fmt->bpp;
> +}
> +
> +static bool dw_dp_needs_link_retrain(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> + u8 link_status[DP_LINK_STATUS_SIZE];
> +
> + if (!dw_dp_link_train_valid(&link->train))
> + return false;
> +
> + if (drm_dp_dpcd_read_link_status(&dp->aux, link_status) < 0)
> + return false;
> +
> + /* Retrain if Channel EQ or CR not ok */
> + return !drm_dp_channel_eq_ok(link_status, dp->link.lanes);
> +}
> +
> +static void dw_dp_link_disable(struct dw_dp *dp)
> +{
> + struct dw_dp_link *link = &dp->link;
> +
> + if (dw_dp_hpd_detect(dp))
> + dw_dp_link_power_down(dp);
> +
> + dw_dp_phy_xmit_enable(dp, 0);
> +
> + phy_power_off(dp->phy);
> +
> + link->train.clock_recovered = false;
> + link->train.channel_equalized = false;
> +}
> +
> +static int dw_dp_link_enable(struct dw_dp *dp)
> +{
> + int ret;
> +
> + ret = phy_power_on(dp->phy);
> + if (ret)
> + return ret;
> +
> + ret = dw_dp_link_power_up(dp);
> + if (ret < 0)
> + return ret;
> +
> + ret = dw_dp_link_train(dp);
> +
> + return ret;
> +}
> +
> +static void dw_dp_bridge_atomic_enable(struct drm_bridge *bridge,
> + struct drm_bridge_state *old_state)
> +{
> + struct dw_dp *dp = bridge_to_dp(bridge);
> + struct drm_atomic_state *state = old_state->base.state;
> + struct drm_connector *connector;
> + struct drm_connector_state *conn_state;
> + int ret;
> +
> + connector = drm_atomic_get_new_connector_for_encoder(state, bridge->encoder);
> + if (!connector) {
> + dev_err(dp->dev, "failed to get connector\n");
> + return;
> + }
> +
> + conn_state = drm_atomic_get_new_connector_state(state, connector);
> + if (!conn_state) {
> + dev_err(dp->dev, "failed to get connector state\n");
> + return;
> + }
> +
> + set_bit(0, dp->sdp_reg_bank);
> +
> + ret = dw_dp_link_enable(dp);
> + if (ret < 0) {
> + dev_err(dp->dev, "failed to enable link: %d\n", ret);
> + return;
> + }
> +
> + ret = dw_dp_video_enable(dp);
> + if (ret < 0) {
> + dev_err(dp->dev, "failed to enable video: %d\n", ret);
> + return;
> + }
> +}
> +
> +static void dw_dp_reset(struct dw_dp *dp)
> +{
> + int val;
> +
> + disable_irq(dp->irq);
> + regmap_update_bits(dp->regmap, DW_DP_SOFT_RESET_CTRL, CONTROLLER_RESET,
> + FIELD_PREP(CONTROLLER_RESET, 1));
> + udelay(10);
> + regmap_update_bits(dp->regmap, DW_DP_SOFT_RESET_CTRL, CONTROLLER_RESET,
> + FIELD_PREP(CONTROLLER_RESET, 0));
> +
> + dw_dp_init_hw(dp);
> + regmap_read_poll_timeout(dp->regmap, DW_DP_HPD_STATUS, val,
> + FIELD_GET(HPD_HOT_PLUG, val), 200, 200000);
> + regmap_write(dp->regmap, DW_DP_HPD_STATUS, HPD_HOT_PLUG);
> + enable_irq(dp->irq);
> +}
> +
> +static void dw_dp_bridge_atomic_disable(struct drm_bridge *bridge,
> + struct drm_bridge_state *old_bridge_state)
> +{
> + struct dw_dp *dp = bridge_to_dp(bridge);
> +
> + dw_dp_video_disable(dp);
> + dw_dp_link_disable(dp);
> + bitmap_zero(dp->sdp_reg_bank, SDP_REG_BANK_SIZE);
> + dw_dp_reset(dp);
> +}
> +
> +static bool dw_dp_hpd_detect_link(struct dw_dp *dp)
> +{
> + int ret;
> +
> + ret = phy_power_on(dp->phy);
> + if (ret < 0)
> + return false;
> + ret = dw_dp_link_parse(dp);
> + phy_power_off(dp->phy);
> +
> + return !ret;
> +}
> +
> +static enum drm_connector_status dw_dp_bridge_detect(struct drm_bridge *bridge)
> +{
> + struct dw_dp *dp = bridge_to_dp(bridge);
> +
> + if (!dw_dp_hpd_detect(dp))
> + return connector_status_disconnected;
> +
> + if (!dw_dp_hpd_detect_link(dp))
> + return connector_status_disconnected;
> +
> + return connector_status_connected;
> +}
> +
> +static const struct drm_edid *dw_dp_bridge_edid_read(struct drm_bridge *bridge,
> + struct drm_connector *connector)
> +{
> + struct dw_dp *dp = bridge_to_dp(bridge);
> + const struct drm_edid *edid;
> + int ret;
> +
> + ret = phy_power_on(dp->phy);
> + if (ret)
> + return NULL;
> +
> + edid = drm_edid_read_ddc(connector, &dp->aux.ddc);
> +
> + phy_power_off(dp->phy);
> +
> + return edid;
> +}
> +
> +static u32 *dw_dp_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
> + struct drm_bridge_state *bridge_state,
> + struct drm_crtc_state *crtc_state,
> + struct drm_connector_state *conn_state,
> + unsigned int *num_output_fmts)
> +{
> + struct dw_dp *dp = bridge_to_dp(bridge);
> + struct dw_dp_link *link = &dp->link;
> + struct drm_display_info *di = &conn_state->connector->display_info;
> + struct drm_display_mode mode = crtc_state->mode;
> + const struct dw_dp_output_format *fmt;
> + u32 i, j = 0;
> + u32 *output_fmts;
> +
> + *num_output_fmts = 0;
> +
> + output_fmts = kcalloc(ARRAY_SIZE(dw_dp_output_formats), sizeof(*output_fmts), GFP_KERNEL);
> + if (!output_fmts)
> + return NULL;
> +
> + for (i = 0; i < ARRAY_SIZE(dw_dp_output_formats); i++) {
> + fmt = &dw_dp_output_formats[i];
> +
> + if (fmt->bpc > conn_state->max_bpc)
> + continue;
> +
> + if (!(fmt->color_format & di->color_formats))
> + continue;
> +
> + if (fmt->color_format == DRM_COLOR_FORMAT_YCBCR420 &&
> + !link->vsc_sdp_supported)
> + continue;
> +
> + if (fmt->color_format != DRM_COLOR_FORMAT_YCBCR420 &&
> + drm_mode_is_420_only(di, &mode))
> + continue;
> +
> + if (!dw_dp_bandwidth_ok(dp, &mode, fmt->bpp, link->lanes, link->rate))
> + continue;
> +
> + output_fmts[j++] = fmt->bus_format;
> + }
> +
> + *num_output_fmts = j;
> +
> + return output_fmts;
> +}
> +
> +static const struct drm_bridge_funcs dw_dp_bridge_funcs = {
> + .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
> + .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
> + .atomic_reset = drm_atomic_helper_bridge_reset,
> + .atomic_get_input_bus_fmts = drm_atomic_helper_bridge_propagate_bus_fmt,
> + .atomic_get_output_bus_fmts = dw_dp_bridge_atomic_get_output_bus_fmts,
> + .mode_fixup = dw_dp_bridge_mode_fixup,
> + .mode_valid = dw_dp_bridge_mode_valid,
> + .atomic_pre_enable = dw_dp_bridge_atomic_pre_enable,
> + .atomic_enable = dw_dp_bridge_atomic_enable,
> + .atomic_disable = dw_dp_bridge_atomic_disable,
> + .detect = dw_dp_bridge_detect,
> + .edid_read = dw_dp_bridge_edid_read,
> +};
> +
> +static int dw_dp_link_retrain(struct dw_dp *dp)
> +{
> + struct drm_device *dev = dp->bridge.dev;
> + struct drm_modeset_acquire_ctx ctx;
> + int ret;
> +
> + if (!dw_dp_needs_link_retrain(dp))
> + return 0;
> +
> + dev_dbg(dp->dev, "Retraining link\n");
> +
> + drm_modeset_acquire_init(&ctx, 0);
> + for (;;) {
> + ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx);
> + if (ret != -EDEADLK)
> + break;
I think it's an error to continue in such a case. There should be a
return after the loop if ret is not 0.
> +
> + drm_modeset_backoff(&ctx);
> + }
> +
> + ret = dw_dp_link_train(dp);
> + drm_modeset_drop_locks(&ctx);
> + drm_modeset_acquire_fini(&ctx);
> +
> + return ret;
> +}
> +
> +static void dw_dp_hpd_work(struct work_struct *work)
> +{
> + struct dw_dp *dp = container_of(work, struct dw_dp, hpd_work);
> + bool long_hpd;
> + int ret;
> +
> + mutex_lock(&dp->irq_lock);
> + long_hpd = dp->hotplug.long_hpd;
> + mutex_unlock(&dp->irq_lock);
> +
> + dev_dbg(dp->dev, "[drm] Get hpd irq - %s\n", long_hpd ? "long" : "short");
> +
> + if (!long_hpd) {
> + if (dw_dp_needs_link_retrain(dp)) {
> + ret = dw_dp_link_retrain(dp);
> + if (ret)
> + dev_warn(dp->dev, "Retrain link failed\n");
> + }
> + } else {
> + drm_helper_hpd_irq_event(dp->bridge.dev);
> + }
> +}
> +
> +static void dw_dp_handle_hpd_event(struct dw_dp *dp)
> +{
> + u32 value;
> +
> + mutex_lock(&dp->irq_lock);
> + regmap_read(dp->regmap, DW_DP_HPD_STATUS, &value);
> +
> + if (value & HPD_IRQ) {
> + dev_dbg(dp->dev, "IRQ from the HPD\n");
> + dp->hotplug.long_hpd = false;
> + regmap_write(dp->regmap, DW_DP_HPD_STATUS, HPD_IRQ);
> + }
> +
> + if (value & HPD_HOT_PLUG) {
> + dev_dbg(dp->dev, "Hot plug detected\n");
> + dp->hotplug.long_hpd = true;
> + regmap_write(dp->regmap, DW_DP_HPD_STATUS, HPD_HOT_PLUG);
> + }
> +
> + if (value & HPD_HOT_UNPLUG) {
> + dev_dbg(dp->dev, "Unplug detected\n");
> + dp->hotplug.long_hpd = true;
> + regmap_write(dp->regmap, DW_DP_HPD_STATUS, HPD_HOT_UNPLUG);
> + }
> + mutex_unlock(&dp->irq_lock);
> +
> + schedule_work(&dp->hpd_work);
> +}
> +
> +static irqreturn_t dw_dp_irq(int irq, void *data)
> +{
> + struct dw_dp *dp = data;
> + u32 value;
> +
> + regmap_read(dp->regmap, DW_DP_GENERAL_INTERRUPT, &value);
> + if (!value)
> + return IRQ_NONE;
> +
> + if (value & HPD_EVENT)
> + dw_dp_handle_hpd_event(dp);
> +
> + if (value & AUX_REPLY_EVENT) {
> + regmap_write(dp->regmap, DW_DP_GENERAL_INTERRUPT, AUX_REPLY_EVENT);
> + complete(&dp->complete);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static const struct regmap_range dw_dp_readable_ranges[] = {
> + regmap_reg_range(DW_DP_VERSION_NUMBER, DW_DP_ID),
> + regmap_reg_range(DW_DP_CONFIG_REG1, DW_DP_CONFIG_REG3),
> + regmap_reg_range(DW_DP_CCTL, DW_DP_SOFT_RESET_CTRL),
> + regmap_reg_range(DW_DP_VSAMPLE_CTRL, DW_DP_VIDEO_HBLANK_INTERVAL),
> + regmap_reg_range(DW_DP_AUD_CONFIG1, DW_DP_AUD_CONFIG1),
> + regmap_reg_range(DW_DP_SDP_VERTICAL_CTRL, DW_DP_SDP_STATUS_EN),
> + regmap_reg_range(DW_DP_PHYIF_CTRL, DW_DP_PHYIF_PWRDOWN_CTRL),
> + regmap_reg_range(DW_DP_AUX_CMD, DW_DP_AUX_DATA3),
> + regmap_reg_range(DW_DP_GENERAL_INTERRUPT, DW_DP_HPD_INTERRUPT_ENABLE),
> +};
> +
> +static const struct regmap_access_table dw_dp_readable_table = {
> + .yes_ranges = dw_dp_readable_ranges,
> + .n_yes_ranges = ARRAY_SIZE(dw_dp_readable_ranges),
> +};
> +
> +static const struct regmap_config dw_dp_regmap_config = {
> + .reg_bits = 32,
> + .reg_stride = 4,
> + .val_bits = 32,
> + .fast_io = true,
> + .max_register = DW_DP_MAX_REGISTER,
> + .rd_table = &dw_dp_readable_table,
> +};
> +
> +struct dw_dp *dw_dp_bind(struct device *dev, struct drm_encoder *encoder,
> + const struct dw_dp_plat_data *plat_data)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct dw_dp *dp;
> + struct drm_bridge *bridge;
> + void __iomem *res;
> + int ret;
> +
> + dp = devm_kzalloc(dev, sizeof(*dp), GFP_KERNEL);
> + if (!dp)
> + return ERR_PTR(-ENOMEM);
> +
> + dp->dev = dev;
> + dp->video.pixel_mode = DW_DP_MP_QUAD_PIXEL;
> +
> + dp->plat_data = plat_data;
> + bridge = &dp->bridge;
> + mutex_init(&dp->irq_lock);
> + INIT_WORK(&dp->hpd_work, dw_dp_hpd_work);
> + init_completion(&dp->complete);
> +
> + res = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(res))
> + return ERR_CAST(res);
> +
> + dp->regmap = devm_regmap_init_mmio(dev, res, &dw_dp_regmap_config);
> + if (IS_ERR(dp->regmap)) {
> + dev_err_probe(dev, PTR_ERR(dp->regmap), "failed to create regmap\n");
> + return ERR_CAST(dp->regmap);
> + }
> +
> + dp->phy = devm_of_phy_get(dev, dev->of_node, NULL);
> + if (IS_ERR(dp->phy)) {
> + dev_err_probe(dev, PTR_ERR(dp->phy), "failed to get phy\n");
> + return ERR_CAST(dp->phy);
> + }
> +
> + dp->apb_clk = devm_clk_get_enabled(dev, "apb");
> + if (IS_ERR(dp->apb_clk)) {
> + dev_err_probe(dev, PTR_ERR(dp->apb_clk), "failed to get apb clock\n");
> + return ERR_CAST(dp->apb_clk);
> + }
> +
> + dp->aux_clk = devm_clk_get_enabled(dev, "aux");
> + if (IS_ERR(dp->aux_clk)) {
> + dev_err_probe(dev, PTR_ERR(dp->aux_clk), "failed to get aux clock\n");
> + return ERR_CAST(dp->aux_clk);
> + }
> +
> + dp->i2s_clk = devm_clk_get(dev, "i2s");
> + if (IS_ERR(dp->i2s_clk)) {
> + dev_err_probe(dev, PTR_ERR(dp->i2s_clk), "failed to get i2s clock\n");
> + return ERR_CAST(dp->i2s_clk);
> + }
> +
> + dp->spdif_clk = devm_clk_get(dev, "spdif");
> + if (IS_ERR(dp->spdif_clk)) {
> + dev_err_probe(dev, PTR_ERR(dp->spdif_clk), "failed to get spdif clock\n");
> + return ERR_CAST(dp->spdif_clk);
> + }
> +
> + dp->hdcp_clk = devm_clk_get(dev, "hdcp");
> + if (IS_ERR(dp->hdcp_clk)) {
> + dev_err_probe(dev, PTR_ERR(dp->hdcp_clk), "failed to get hdcp clock\n");
> + return ERR_CAST(dp->hdcp_clk);
> + }
> +
> + dp->rstc = devm_reset_control_get(dev, NULL);
> + if (IS_ERR(dp->rstc)) {
> + dev_err_probe(dev, PTR_ERR(dp->rstc), "failed to get reset control\n");
> + return ERR_CAST(dp->rstc);
> + }
> +
> + dp->irq = platform_get_irq(pdev, 0);
> + if (dp->irq < 0)
> + return ERR_PTR(ret);
> +
> + ret = devm_request_threaded_irq(dev, dp->irq, NULL, dw_dp_irq,
> + IRQF_ONESHOT, dev_name(dev), dp);
Are you ready to handle the IRQ here, before the bridge is filled?
> + if (ret) {
> + dev_err_probe(dev, ret, "failed to request irq\n");
> + return ERR_PTR(ret);
> + }
> +
> + bridge->of_node = dev->of_node;
> + bridge->funcs = &dw_dp_bridge_funcs;
> + bridge->ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID | DRM_BRIDGE_OP_HPD;
> + bridge->type = DRM_MODE_CONNECTOR_DisplayPort;
> + bridge->ycbcr_420_allowed = true;
> + bridge->vendor = "Synopsys";
> + bridge->product = "DW DP TX";
These two are unused
> +
> + platform_set_drvdata(pdev, dp);
Unused
> +
> + dp->aux.dev = dev;
> + dp->aux.drm_dev = encoder->dev;
> + dp->aux.name = dev_name(dev);
> + dp->aux.transfer = dw_dp_aux_transfer;
> + ret = drm_dp_aux_register(&dp->aux);
> + if (ret) {
> + dev_err_probe(dev, ret, "Aux register failed\n");
> + return ERR_PTR(ret);
> + }
> +
> + ret = drm_bridge_attach(encoder, bridge, NULL, DRM_BRIDGE_ATTACH_NO_CONNECTOR);
> + if (ret)
> + dev_err_probe(dev, ret, "Failed to attach bridge\n");
> +
> + dw_dp_init_hw(dp);
> +
> + return dp;
> +}
> +MODULE_AUTHOR("Andy Yan <andyshrk@xxxxxxx>");
> +MODULE_DESCRIPTION("DW DP Core Library");
> +MODULE_LICENSE("GPL");
> diff --git a/include/drm/bridge/dw_dp.h b/include/drm/bridge/dw_dp.h
> new file mode 100644
> index 000000000000..07845f609eca
> --- /dev/null
> +++ b/include/drm/bridge/dw_dp.h
> @@ -0,0 +1,19 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * Copyright (c) 2025 Rockchip Electronics Co., Ltd.
> + */
> +
> +#ifndef __DW_DP__
> +#define __DW_DP__
> +
> +struct device;
> +struct drm_encoder;
> +struct dw_dp;
> +
> +struct dw_dp_plat_data {
> + u32 max_link_rate;
> +};
> +
> +struct dw_dp *dw_dp_bind(struct device *dev, struct drm_encoder *encoder,
> + const struct dw_dp_plat_data *plat_data);
> +#endif /* __DW_DP__ */
> --
> 2.34.1
>
--
With best wishes
Dmitry
