Add a driver for Cadence DPI -> DSI bridge. This driver only support a subset of Cadence DSI bridge capabilities. Here is a non-exhaustive list of missing features: * burst mode * dynamic configuration of the DPHY based on the * support for additional input interfaces (SDI input) Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx> --- Changes in v3: - replace magic values by real timing calculation. The DPHY PLL clock is still hardcoded since we don't have a working DPHY block yet, and this is the piece of HW we need to dynamically configure the PLL rate based on the display refresh rate and the resolution. - parse DSI devices represented with the OF-graph. This is needed to support DSI devices controlled through an external bus like I2C or SPI. - use the DRM panel-bridge infrastructure to simplify the DRM panel logic Changes in v2: - rebase on v4.12-rc1 and adapt to driver to the drm_bridge API changes - return the correct error when devm_clk_get(sysclk) fails - add missing depends on OF and select DRM_PANEL in the Kconfig entry --- drivers/gpu/drm/bridge/Kconfig | 9 + drivers/gpu/drm/bridge/Makefile | 1 + drivers/gpu/drm/bridge/cdns-dsi.c | 1090 +++++++++++++++++++++++++++++++++++++ 3 files changed, 1100 insertions(+) create mode 100644 drivers/gpu/drm/bridge/cdns-dsi.c diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig index adf9ae0e0b7c..88c324b12e16 100644 --- a/drivers/gpu/drm/bridge/Kconfig +++ b/drivers/gpu/drm/bridge/Kconfig @@ -25,6 +25,15 @@ config DRM_ANALOGIX_ANX78XX the HDMI output of an application processor to MyDP or DisplayPort. +config DRM_CDNS_DSI + tristate "Cadence DPI/DSI bridge" + select DRM_KMS_HELPER + select DRM_MIPI_DSI + select DRM_PANEL + depends on OF + help + Support Cadence DPI to DSI bridge. + config DRM_DUMB_VGA_DAC tristate "Dumb VGA DAC Bridge support" depends on OF diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile index defcf1e7ca1c..77b65e8ecf59 100644 --- a/drivers/gpu/drm/bridge/Makefile +++ b/drivers/gpu/drm/bridge/Makefile @@ -1,4 +1,5 @@ obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o +obj-$(CONFIG_DRM_CDNS_DSI) += cdns-dsi.o obj-$(CONFIG_DRM_DUMB_VGA_DAC) += dumb-vga-dac.o obj-$(CONFIG_DRM_LVDS_ENCODER) += lvds-encoder.o obj-$(CONFIG_DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW) += megachips-stdpxxxx-ge-b850v3-fw.o diff --git a/drivers/gpu/drm/bridge/cdns-dsi.c b/drivers/gpu/drm/bridge/cdns-dsi.c new file mode 100644 index 000000000000..f5dc26c90b20 --- /dev/null +++ b/drivers/gpu/drm/bridge/cdns-dsi.c @@ -0,0 +1,1090 @@ +/* + * Copyright: 2017 Cadence Design Systems, Inc. + * + * Author: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx> + * + * 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/>. + */ + +#include <drm/drm_atomic_helper.h> +#include <drm/drm_bridge.h> +#include <drm/drm_crtc_helper.h> +#include <drm/drm_mipi_dsi.h> +#include <drm/drm_panel.h> +#include <video/mipi_display.h> + +#include <linux/clk.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of_graph.h> +#include <linux/platform_device.h> + +#define IP_CONF 0x0 +#define SP_HS_FIFO_DEPTH(x) (((x) & GENMASK(30, 26)) >> 26) +#define SP_LP_FIFO_DEPTH(x) (((x) & GENMASK(25, 21)) >> 21) +#define VRS_FIFO_DEPTH(x) (((x) & GENMASK(20, 16)) >> 16) +#define DIRCMD_FIFO_DEPTH(x) (((x) & GENMASK(15, 13)) >> 13) +#define SDI_IFACE_32 BIT(12) +#define INTERNAL_DATAPATH_32 (0 << 10) +#define INTERNAL_DATAPATH_16 (1 << 10) +#define INTERNAL_DATAPATH_8 (3 << 10) +#define INTERNAL_DATAPATH_SIZE ((x) & GENMASK(11, 10)) +#define INTERNAL_DATAPATH_32 (0 << 10) +#define INTERNAL_DATAPATH_16 (1 << 10) +#define INTERNAL_DATAPATH_8 (3 << 10) +#define NUM_IFACE(x) ((((x) & GENMASK(9, 8)) >> 8) + 1) +#define MAX_LANE_NB(x) (((x) & GENMASK(7, 6)) >> 6) +#define RX_FIFO_DEPTH(x) ((x) & GENMASK(5, 0)) + +#define MCTL_MAIN_DATA_CTL 0x4 +#define TE_MIPI_POLLING_EN BIT(25) +#define TE_HW_POLLING_EN BIT(24) +#define DISP_EOT_GEN BIT(18) +#define HOST_EOT_GEN BIT(17) +#define DISP_GEN_CHECKSUM BIT(16) +#define DISP_GEN_ECC BIT(15) +#define BTA_EN BIT(14) +#define READ_EN BIT(13) +#define REG_TE_EN BIT(12) +#define IF_TE_EN(x) BIT(8 + (x)) +#define TBG_SEL BIT(7) +#define TVG_SEL BIT(6) +#define VID_EN BIT(5) +#define IF_VID_SELECT(x) ((x) << 2) +#define IF_VID_SELECT_MASK GENMASK(4, 2) +#define IF_VID_MODE BIT(1) +#define LINK_EN BIT(0) + +#define MCTL_MAIN_PHY_CTL 0x8 +#define CLK_FORCE_STOP BIT(14) +#define WAIT_BURST_TIME(x) ((x) << 10) +#define DATA_ULPM_EN(x) BIT(6 + (x)) +#define CLK_ULPM_EN BIT(5) +#define CLK_CONTINUOUS BIT(4) +#define DATA_FORCE_STOP BIT(3) +#define DATA_LANE_EN(x) BIT((x) - 1) + +#define MCTL_LANE_STS 0x10 +#define LANE_STATE_START 0 +#define LANE_STATE_IDLE 1 +#define LANE_STATE_WRITE 2 +#define LANE_STATE_ULPM 3 +#define LANE_STATE_READ 4 +#define DATA_LANE_STATE(l, val) \ + (((val) >> (2 + 2 * (l) + ((l) ? 1 : 0))) & GENMASK((l) ? 1 : 2, 0)) +#define CLK_LANE_STATE_HS 2 +#define CLK_LANE_STATE(val) ((val) & GENMASK(1, 0)) + +#define MCTL_DPHY_TIMEOUT1 0x14 +#define CLK_DIV(x) (x) +#define CLK_DIV_MAX GENMASK(3, 0) +#define HSTX_TIMEOUT(x) ((x) << 4) +#define HSTX_TIMEOUT_MAX GENMASK(21, 4) + +#define MCTL_DPHY_TIMEOUT2 0x18 +#define LPRX_TIMEOUT(x) (x) + +#define MCTL_ULPOUT_TIME 0x1c +#define DATA_LANE_ULPOUT_TIME(x) ((x) << 9) +#define CLK_LANE_ULPOUT_TIME(x) (x) + +#define MCTL_DPHY_STATIC 0x20 +#define INVERT_DATA_HS(l) BIT((l) * (2 + 1) + 1) +#define SWAP_DATA_PINS(l) BIT((l) * (2 + 1)) +#define INVERT_CLK_HS BIT(1) +#define SWAP_CLK_PINS BIT(0) + +#define MCTL_MAIN_EN 0x24 +#define IF_EN(x) BIT(13 + (x)) +#define DATA_LANE_ULPM_REQ(l) BIT(9 + (l)) +#define CLK_LANE_ULPM_REQ BIT(8) +#define DATA_LANE_START(x) BIT(4 + (x)) +#define CLK_LANE_EN BIT(3) +#define PLL_START BIT(0) + +#define MCTL_MAIN_STS 0x28 +#define MCTL_MAIN_STS_CTL 0x130 +#define MCTL_MAIN_STS_CLR 0x150 +#define MCTL_MAIN_STS_FLAG 0x170 +#define IF_UNTERM_PKT_ERR(x) BIT(8 + (x)) +#define LPRX_TIMEOUT_ERR BIT(7) +#define HSTX_TIMEOUT_ERR BIT(6) +#define DATA_LANE_RDY(l) BIT(2 + (l)) +#define CLK_LANE_RDY BIT(1) +#define PLL_LOCKED BIT(0) + +#define MCTL_DPHY_ERR 0x2c +#define MCTL_DPHY_ERR_CTL1 0x148 +#define MCTL_DPHY_ERR_CLR 0x168 +#define MCTL_DPHY_ERR_FLAG 0x188 +#define ERR_CONT_LP(x, l) BIT(18 + ((x) * 4) + (l)) +#define ERR_CONTROL(l) BIT(14 + (l)) +#define ERR_SYNESC(l) BIT(10 + (l)) +#define ERR_ESC(l) BIT(6 + (l)) + +#define MCTL_DPHY_ERR_CTL2 0x14c +#define ERR_CONT_LP_EDGE(x, l) BIT(12 + ((x) * 4) + (l)) +#define ERR_CONTROL_EDGE(l) BIT(8 + (l)) +#define ERR_SYN_ESC_EDGE(l) BIT(4 + (l)) +#define ERR_ESC_EDGE(l) BIT(0 + (l)) + +#define CMD_MODE_CTL 0x70 +#define IF_VCHAN_ID(x, c) ((c) << ((x) * 2)) +#define IF_LP_EN(x) BIT(9 + (x)) + +#define CMD_MODE_CTL2 0x74 +#define TE_TIMEOUT(x) ((x) << 11) +#define FILL_VALUE(x) ((x) << 3) +#define ARB_IF_WITH_HIGHEST_PRIORITY(x) ((x) << 1) +#define ARB_ROUND_ROBIN_MODE BIT(0) + +#define CMD_MODE_STS 0x78 +#define CMD_MODE_STS_CTL 0x134 +#define CMD_MODE_STS_CLR 0x154 +#define CMD_MODE_STS_FLAG 0x174 +#define ERR_IF_UNDERRUN(x) BIT(4 + (x)) +#define ERR_UNWANTED_READ BIT(3) +#define ERR_TE_MISS BIT(2) +#define ERR_NO_TE BIT(1) +#define CSM_RUNNING BIT(0) + +#define DIRECT_CMD_SEND 0x80 + +#define DIRECT_CMD_MAIN_SETTINGS 0x84 +#define TRIGGER_VAL(x) ((x) << 25) +#define CMD_LP_EN BIT(24) +#define CMD_SIZE(x) ((x) << 16) +#define CMD_VCHAN_ID(x) ((x) << 14) +#define CMD_DATATYPE(x) ((x) << 8) +#define CMD_LONG BIT(3) +#define WRITE_CMD 0 +#define READ_CMD 1 +#define TE_REQ 4 +#define TRIGGER_REQ 5 +#define BTA_REQ 6 + +#define DIRECT_CMD_STS 0x88 +#define DIRECT_CMD_STS_CTL 0x138 +#define DIRECT_CMD_STS_CLR 0x158 +#define DIRECT_CMD_STS_FLAG 0x178 +#define RCVD_ACK_VAL(val) ((val) >> 16) +#define RCVD_TRIGGER_VAL(val) (((val) & GENMASK(14, 11)) >> 11) +#define READ_COMPLETED_WITH_ERR BIT(10) +#define BTA_FINISHED BIT(9) +#define BTA_COMPLETED BIT(8) +#define TE_RCVD BIT(7) +#define TRIGGER_RCVD BIT(6) +#define ACK_WITH_ERR_RCVD BIT(5) +#define ACK_RCVD BIT(4) +#define READ_COMPLETED BIT(3) +#define TRIGGER_COMPLETED BIT(2) +#define WRITE_COMPLETED BIT(1) +#define SENDING_CMD BIT(0) + +#define DIRECT_CMD_STOP_READ 0x8c + +#define DIRECT_CMD_WRDATA 0x90 +#define WRDAT(x, val) ((val) << ((x) * 8)) + +#define DIRECT_CMD_FIFO_RST 0x94 + +#define DIRECT_CMD_RDDATA 0xa0 +#define RDDAT(x, val) (((val) >> ((x) * 8)) & GENMASK(7, 0)) + +#define DIRECT_CMD_RD_PROPS 0xa4 +#define RD_DCS BIT(18) +#define RD_VCHAN_ID(val) (((val) >> 16) & GENMASK(1, 0)) +#define RD_SIZE(val) ((val) & GENMASK(15, 0)) + +#define DIRECT_CMD_RD_STS 0xa8 +#define DIRECT_CMD_RD_STS_CTL 0x13c +#define DIRECT_CMD_RD_STS_CLR 0x15c +#define DIRECT_CMD_RD_STS_FLAG 0x17c +#define ERR_EOT_WITH_ERR BIT(8) +#define ERR_MISSING_EOT BIT(7) +#define ERR_WRONG_LENGTH BIT(6) +#define ERR_OVERSIZE BIT(5) +#define ERR_RECEIVE BIT(4) +#define ERR_UNDECODABLE BIT(3) +#define ERR_CHECKSUM BIT(2) +#define ERR_UNCORRECTABLE BIT(1) +#define ERR_FIXED BIT(0) + +#define VID_MAIN_CTL 0xb0 +#define VID_FIELD_SW BIT(28) +#define VID_INTERLACED_EN BIT(27) +#define RECOVERY_MODE(x) ((x) << 25) +#define RECOVERY_MODE_NEXT_HSYNC 0 +#define RECOVERY_MODE_NEXT_STOP_POINT 2 +#define RECOVERY_MODE_NEXT_VSYNC 3 +#define REG_BLKEOL_MODE(x) ((x) << 23) +#define REG_BLKLINE_MODE(x) ((x) << 21) +#define REG_BLK_MODE_NULL_PKT 0 +#define REG_BLK_MODE_BLANKING_PKT 1 +#define REG_BLK_MODE_LP 2 +#define SYNC_PULSE_HORIZONTAL BIT(20) +#define SYNC_PULSE_ACTIVE BIT(19) +#define BURST_MODE BIT(18) +#define VID_PIXEL_MODE_MASK GENMASK(17, 14) +#define VID_PIXEL_MODE_RGB565 (0 << 14) +#define VID_PIXEL_MODE_RGB666_PACKED (1 << 14) +#define VID_PIXEL_MODE_RGB666 (2 << 14) +#define VID_PIXEL_MODE_RGB888 (3 << 14) +#define VID_PIXEL_MODE_RGB101010 (4 << 14) +#define VID_PIXEL_MODE_RGB121212 (5 << 14) +#define VID_PIXEL_MODE_YUV420 (8 << 14) +#define VID_PIXEL_MODE_YUV422_PACKED (9 << 14) +#define VID_PIXEL_MODE_YUV422 (10 << 14) +#define VID_PIXEL_MODE_YUV422_24B (11 << 14) +#define VID_DATATYPE(x) ((x) << 8) +#define VID_VIRTCHAN_ID(iface, x) ((x) << (4 + (iface) * 2)) +#define STOP_MODE(x) ((x) << 2) +#define START_MODE(x) (x) + +#define VID_VSIZE1 0xb4 +#define VFP_LEN(x) ((x) << 12) +#define VBP_LEN(x) ((x) << 6) +#define VSA_LEN(x) (x) + +#define VID_VSIZE2 0xb8 +#define VACT_LEN(x) (x) + +#define VID_HSIZE1 0xc0 +#define HFP_LEN(x) ((x) << 20) +#define HBP_LEN(x) ((x) << 10) +#define HSA_LEN(x) (x) + +#define VID_HSIZE2 0xc4 +#define HACT_LEN(x) (x) + +#define VID_BLKSIZE1 0xcc +#define BLK_EOL_PKT_LEN(x) ((x) << 15) +#define BLK_LINE_EVENT_PKT_LEN(x) (x) + +#define VID_BLKSIZE2 0xd0 +#define BLK_LINE_PULSE_PKT_LEN(x) (x) + +#define VID_PKT_TIME 0xd8 +#define BLK_EOL_DURATION(x) (x) + +#define VID_DPHY_TIME 0xdc +#define REG_WAKEUP_TIME(x) ((x) << 17) +#define REG_LINE_DURATION(x) (x) + +#define VID_ERR_COLOR1 0xe0 +#define COL_GREEN(x) ((x) << 12) +#define COL_RED(x) (x) + +#define VID_ERR_COLOR2 0xe4 +#define PAD_VAL(x) ((x) << 12) +#define COL_BLUE(x) (x) + +#define VID_VPOS 0xe8 +#define LINE_VAL(val) (((val) & GENMASK(14, 2)) >> 2) +#define LINE_POS(val) ((val) & GENMASK(1, 0)) + +#define VID_HPOS 0xec +#define HORIZ_VAL(val) (((val) & GENMASK(17, 3)) >> 3) +#define HORIZ_POS(val) ((val) & GENMASK(2, 0)) + +#define VID_MODE_STS 0xf0 +#define VID_MODE_STS_CTL 0x140 +#define VID_MODE_STS_CLR 0x160 +#define VID_MODE_STS_FLAG 0x180 +#define VSG_RECOVERY BIT(10) +#define ERR_VRS_WRONG_LEN BIT(9) +#define ERR_LONG_READ BIT(8) +#define ERR_LINE_WRITE BIT(7) +#define ERR_BURST_WRITE BIT(6) +#define ERR_SMALL_HEIGHT BIT(5) +#define ERR_SMALL_LEN BIT(4) +#define ERR_MISSING_VSYNC BIT(3) +#define ERR_MISSING_HSYNC BIT(2) +#define ERR_MISSING_DATA BIT(1) +#define VSG_RUNNING BIT(0) + +#define VID_VCA_SETTING1 0xf4 +#define BURST_LP BIT(16) +#define MAX_BURST_LIMIT(x) (x) + +#define VID_VCA_SETTING2 0xf8 +#define MAX_LINE_LIMIT(x) ((x) << 16) +#define EXACT_BURST_LIMIT(x) (x) + +#define TVG_CTL 0xfc +#define TVG_STRIPE_SIZE(x) ((x) << 5) +#define TVG_MODE_MASK GENMASK(4, 3) +#define TVG_MODE_SINGLE_COLOR (0 << 3) +#define TVG_MODE_VSTRIPES (2 << 3) +#define TVG_MODE_HSTRIPES (3 << 3) +#define TVG_STOPMODE_MASK GENMASK(2, 1) +#define TVG_STOPMODE_EOF (0 << 1) +#define TVG_STOPMODE_EOL (1 << 1) +#define TVG_STOPMODE_NOW (2 << 1) +#define TVG_RUN BIT(0) + +#define TVG_IMG_SIZE 0x100 +#define TVG_NBLINES(x) ((x) << 16) +#define TVG_LINE_SIZE(x) (x) + +#define TVG_COLOR1 0x104 +#define TVG_COL1_GREEN(x) ((x) << 12) +#define TVG_COL1_RED(x) (x) + +#define TVG_COLOR1_BIS 0x108 +#define TVG_COL1_BLUE(x) (x) + +#define TVG_COLOR2 0x10c +#define TVG_COL2_GREEN(x) ((x) << 12) +#define TVG_COL2_RED(x) (x) + +#define TVG_COLOR2_BIS 0x110 +#define TVG_COL2_BLUE(x) (x) + +#define TVG_STS 0x114 +#define TVG_STS_RUNNING BIT(0) + +#define TBG_CTL 0x118 +#define TBG_MODE_MASK GENMASK(4, 3) +#define TBG_MODE_START_1B_STOP (0 << 3) +#define TBG_MODE_START_2B_STOP (1 << 3) +#define TBG_MODE_START_BURST_CNT_STOP (2 << 3) +#define TBG_MODE_START_BURST_STOP (3 << 3) +#define TBG_DATA_SEL BIT(2) +#define TBG_HS_REQ BIT(1) +#define TBG_START BIT(0) + +#define TBG_SETTING1 0x11c +#define TBG_SETTING2 0x120 + +#define TBG_STS 0x124 +#define TBG_STS_RUNNING BIT(0) + +#define TVG_TBG_STS_CTL 0x144 +#define TVG_TBG_STS_CLR 0x164 +#define TVG_TBG_STS_FLAG 0x184 +#define TVG_TBG_STS_TBG_RUNNING BIT(1) +#define TVG_TBG_STS_TVG_RUNNING BIT(0) + +#define STS_CTL_EDGE(e) ((e) << 16) + +#define DPHY_LANES_MAP 0x198 +#define DAT_REMAP_CFG(b, l) ((l) << ((b) * 8)) + +#define DPI_IRQ_EN 0x1a0 +#define DPI_IRQ_CLR 0x1a4 +#define DPI_IRQ_STS 0x1a8 +#define PIXEL_BUF_OVERFLOW BIT(0) + +#define DPI_CFG 0x1ac +#define DPI_CFG_FIFO_LEVEL(x) ((x) & GENMASK(15, 0)) +#define DPI_CFG_FIFO_DEPTH(x) ((x) >> 16) + +#define DPHY_CFG0 0x1b0 +#define DPHY_C_RSTB BIT(20) +#define DPHY_D_RSTB(x) ((x) << 16) +#define DPHY_TIF_FORCE_WRITE BIT(12) +#define DPHY_PLL_PDN BIT(10) +#define DPHY_CMN_PDN BIT(9) +#define DPHY_C_PDN BIT(8) +#define DPHY_D_PDN(x) ((x) << 4) +#define DPHY_PLL_PSO BIT(1) +#define DPHY_CMN_PSO BIT(0) + +#define DPHY_CFG1 0x1b4 +#define PDHY_PLL_OPDIV(x) ((x) << 20) +#define PDHY_PLL_IPDIV(x) ((x) << 12) +#define PDHY_PLL_FBDIV(x) (x) + +#define DPHY_PLL_TM_LO 0x1b8 +#define DPHY_PLL_TM_MID 0x1bc +#define DPHY_PLL_TM_HI 0x1c0 + +#define DPHY_STATUS 0x1c4 +#define PPI_D_RX_ULPS_ESC(x) ((x) >> 12) +#define PPI_C_TX_READY_HS BIT(8) +#define PPI_PLL_LOCK BIT(7) +#define PPI_PLL_COARSE BIT(6) +#define PPI_PLL_COARSE_CODE(x) ((x) & GENMASK(5, 0)) + +#define DPHY_BIST 0x1c8 +#define PSO_BYPASS_CTX_EN BIT(12) +#define PSO_BYPASS_TX_EN(l) BIT(8 + (l)) +#define BIST_CTX_EN BIT(4) +#define BIST_TX_EN(l) BIT(l) + +#define TEST_GENERIC 0x1cc +#define TEST_STATUS(x) ((x) >> 16) +#define TEST_CTRL(x) (x) + +#define ID_REG 0x1f0 +#define REV_VENDOR_ID(x) (((x) & GENMASK(31, 20)) >> 20) +#define REV_PRODUCT_ID(x) (((x) & GENMASK(19, 12)) >> 12) +#define REV_HW(x) (((x) & GENMASK(11, 8)) >> 8) +#define REV_MAJOR(x) (((x) & GENMASK(7, 4)) >> 4) +#define REV_MINOR(x) ((x) & GENMASK(3, 0)) + +#define DSI_OUTPUT_PORT 0 +#define DSI_INPUT_PORT(inputid) (1 + (inputid)) + +struct cdns_dsi_output { + struct mipi_dsi_device *dev; + struct drm_panel *panel; + struct drm_bridge *bridge; +}; + +enum cdns_dsi_input_id { + CDNS_DPI_INPUT = 0, +}; + +struct cdns_dsi_input { + enum cdns_dsi_input_id id; + struct drm_bridge bridge; +}; + +struct cdns_dsi { + struct mipi_dsi_host base; + void __iomem *regs; + struct cdns_dsi_input input; + struct cdns_dsi_output output; + unsigned int direct_cmd_fifo_depth; + unsigned int rx_fifo_depth; + struct completion direct_cmd_comp; + struct clk *pclk; + struct clk *sysclk; +}; + +static inline struct cdns_dsi *input_to_dsi(struct cdns_dsi_input *input) +{ + return container_of(input, struct cdns_dsi, input); +} + +static inline struct cdns_dsi *to_cdns_dsi(struct mipi_dsi_host *host) +{ + return container_of(host, struct cdns_dsi, base); +} + +static inline struct cdns_dsi_input * +bridge_to_cdns_dsi_input(struct drm_bridge *bridge) +{ + return container_of(bridge, struct cdns_dsi_input, bridge); +} + +static int cdns_dsi_bridge_attach(struct drm_bridge *bridge) +{ + struct cdns_dsi_input *input = bridge_to_cdns_dsi_input(bridge); + struct cdns_dsi *dsi = input_to_dsi(input); + struct cdns_dsi_output *output = &dsi->output; + + if (!drm_core_check_feature(bridge->dev, DRIVER_ATOMIC)) { + dev_err(dsi->base.dev, + "cdns-dsi driver is only compatible with DRM devices supporting atomic updates"); + return -ENOTSUPP; + } + + return drm_bridge_attach(bridge->encoder, output->bridge, bridge); +} + +static enum drm_mode_status +cdns_dsi_bridge_mode_valid(struct drm_bridge *bridge, + const struct drm_display_mode *mode) +{ + struct cdns_dsi_input *input = bridge_to_cdns_dsi_input(bridge); + struct cdns_dsi *dsi = input_to_dsi(input); + struct cdns_dsi_output *output = &dsi->output; + int bpp; + + /* + * VFP_DSI should be less than VFP_DPI and VFP_DSI should be at + * least 1. + */ + if (mode->vtotal - mode->vsync_end < 2) + return MODE_V_ILLEGAL; + + /* VSA_DSI = VSA_DPI and must be at least 2. */ + if (mode->vsync_end - mode->vsync_start < 2) + return MODE_V_ILLEGAL; + + /* HACT must be a 32-bits aligned. */ + bpp = mipi_dsi_pixel_format_to_bpp(output->dev->format); + if ((mode->hdisplay * bpp) % 32) + return MODE_H_ILLEGAL; + + return MODE_OK; +} + +static void cdns_dsi_bridge_disable(struct drm_bridge *bridge) +{ + struct cdns_dsi_input *input = bridge_to_cdns_dsi_input(bridge); + struct cdns_dsi *dsi = input_to_dsi(input); + u32 val; + + val = readl(dsi->regs + MCTL_MAIN_DATA_CTL); + val &= ~(IF_VID_SELECT_MASK | IF_VID_MODE | VID_EN | HOST_EOT_GEN | + DISP_EOT_GEN); + writel(val, dsi->regs + MCTL_MAIN_DATA_CTL); + + val = readl(dsi->regs + MCTL_MAIN_EN) & ~IF_EN(input->id); + writel(val, dsi->regs + MCTL_MAIN_EN); +} + +#define DSI_HBP_FRAME_OVERHEAD 12 +#define DSI_HSA_FRAME_OVERHEAD 14 +#define DSI_HFP_FRAME_OVERHEAD 6 +#define DSI_HSS_VSS_VSE_FRAME_OVERHEAD 4 +#define DSI_BLANKING_FRAME_OVERHEAD 6 +#define DSI_NULL_FRAME_OVERHEAD 6 +#define DSI_EOT_PKT_SIZE 4 + +#define REG_WAKEUP_TIME_NS 800 +#define DPHY_PLL_RATE_HZ 108000000 + +static void cdns_dsi_bridge_enable(struct drm_bridge *bridge) +{ + struct cdns_dsi_input *input = bridge_to_cdns_dsi_input(bridge); + struct cdns_dsi *dsi = input_to_dsi(input); + struct cdns_dsi_output *output = &dsi->output; + u32 hsize0, hsa, hline, tmp, reg_wakeup, div; + unsigned long dphy_pll_period, tx_byte_period; + struct drm_display_mode *mode; + int bpp, nlanes; + + mode = &bridge->encoder->crtc->state->adjusted_mode; + bpp = mipi_dsi_pixel_format_to_bpp(output->dev->format); + nlanes = output->dev->lanes; + + if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) + tmp = mode->crtc_htotal - mode->crtc_hsync_end; + else + tmp = mode->crtc_htotal - mode->crtc_hsync_start; + tmp = (tmp * bpp) / 8; + tmp = tmp < DSI_HBP_FRAME_OVERHEAD ? 0 : tmp - DSI_HBP_FRAME_OVERHEAD; + hsize0 = HBP_LEN(tmp); + + tmp = mode->crtc_hsync_start - mode->crtc_hdisplay; + tmp = (tmp * bpp) / 8; + tmp = tmp < DSI_HFP_FRAME_OVERHEAD ? 0 : tmp - DSI_HFP_FRAME_OVERHEAD; + hsize0 |= HFP_LEN(tmp); + + if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) + tmp = mode->crtc_hsync_end - mode->crtc_hsync_start; + else + tmp = 0; + tmp = (tmp * 8) / bpp; + tmp = tmp < DSI_HSA_FRAME_OVERHEAD ? 0 : tmp - DSI_HSA_FRAME_OVERHEAD; + hsa = tmp; + hsize0 |= HSA_LEN(tmp); + + writel(hsize0, dsi->regs + VID_HSIZE1); + writel((mode->crtc_hdisplay * bpp) / 8, dsi->regs + VID_HSIZE2); + + writel(VBP_LEN(mode->crtc_vtotal - mode->crtc_vsync_end - 1) | + VFP_LEN(mode->crtc_vsync_start - mode->crtc_vdisplay) | + VSA_LEN(mode->crtc_vsync_end - mode->crtc_vsync_start), + dsi->regs + VID_VSIZE1); + writel(mode->crtc_vdisplay, dsi->regs + VID_VSIZE2); + + hline = (mode->crtc_htotal * bpp) / 8; + tmp = hline - DSI_HSA_FRAME_OVERHEAD; + if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) + tmp -= hsa + DSI_HSA_FRAME_OVERHEAD; + + writel(BLK_LINE_PULSE_PKT_LEN(tmp), dsi->regs + VID_BLKSIZE2); + if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) + writel(MAX_LINE_LIMIT(tmp - DSI_NULL_FRAME_OVERHEAD), + dsi->regs + VID_VCA_SETTING2); + + tmp = hline - + (DSI_HSS_VSS_VSE_FRAME_OVERHEAD + DSI_BLANKING_FRAME_OVERHEAD); + writel(BLK_LINE_EVENT_PKT_LEN(tmp), dsi->regs + VID_BLKSIZE1); + if (!(output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)) + writel(MAX_LINE_LIMIT(tmp - DSI_NULL_FRAME_OVERHEAD), + dsi->regs + VID_VCA_SETTING2); + + tmp = DIV_ROUND_UP(hline, nlanes) - DIV_ROUND_UP(hsa, nlanes); + + if (!(output->dev->mode_flags & MIPI_DSI_MODE_EOT_PACKET)) + tmp -= DIV_ROUND_UP(DSI_EOT_PKT_SIZE, nlanes); + + dphy_pll_period = NSEC_PER_SEC / DPHY_PLL_RATE_HZ; + tx_byte_period = (dphy_pll_period * 2) / 8; + reg_wakeup = REG_WAKEUP_TIME_NS / dphy_pll_period; + writel(REG_WAKEUP_TIME(reg_wakeup) | REG_LINE_DURATION(tmp), + dsi->regs + VID_DPHY_TIME); + + /* + * HSTX and LPRX timeouts are both expressed in TX byte clk cycles and + * both should be set to at least the time it takes to transmit a + * frame. + */ + tmp = NSEC_PER_SEC / mode->vrefresh; + tmp /= tx_byte_period; + + for (div = 0; div <= CLK_DIV_MAX; div++) { + if (tmp <= HSTX_TIMEOUT_MAX) + break; + + tmp >>= 1; + } + + if (tmp > HSTX_TIMEOUT_MAX) + tmp = HSTX_TIMEOUT_MAX; + + writel(CLK_DIV(div) | HSTX_TIMEOUT(tmp), + dsi->regs + MCTL_DPHY_TIMEOUT1); + + writel(LPRX_TIMEOUT(tmp), dsi->regs + MCTL_DPHY_TIMEOUT2); + + if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO) { + switch (output->dev->format) { + case MIPI_DSI_FMT_RGB888: + tmp = VID_PIXEL_MODE_RGB888 | + VID_DATATYPE(MIPI_DSI_PACKED_PIXEL_STREAM_24); + break; + + case MIPI_DSI_FMT_RGB666: + tmp = VID_PIXEL_MODE_RGB666 | + VID_DATATYPE(MIPI_DSI_PIXEL_STREAM_3BYTE_18); + break; + + case MIPI_DSI_FMT_RGB666_PACKED: + tmp = VID_PIXEL_MODE_RGB666_PACKED | + VID_DATATYPE(MIPI_DSI_PACKED_PIXEL_STREAM_18); + break; + + case MIPI_DSI_FMT_RGB565: + tmp = VID_PIXEL_MODE_RGB666_PACKED | + VID_DATATYPE(MIPI_DSI_PACKED_PIXEL_STREAM_16); + break; + + default: + dev_err(dsi->base.dev, "Unsupported DSI format\n"); + return; + } + + if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) + tmp |= SYNC_PULSE_ACTIVE | SYNC_PULSE_HORIZONTAL; + + tmp |= REG_BLKLINE_MODE(REG_BLK_MODE_BLANKING_PKT) | + REG_BLKEOL_MODE(REG_BLK_MODE_BLANKING_PKT) | + RECOVERY_MODE(RECOVERY_MODE_NEXT_HSYNC); + + writel(tmp, dsi->regs + VID_MAIN_CTL); + } + + tmp = readl(dsi->regs + MCTL_MAIN_DATA_CTL); + tmp &= ~(IF_VID_SELECT_MASK | HOST_EOT_GEN | IF_VID_MODE); + + if (!(output->dev->mode_flags & MIPI_DSI_MODE_EOT_PACKET)) + tmp |= HOST_EOT_GEN; + + if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO) + tmp |= IF_VID_MODE | IF_VID_SELECT(input->id) | VID_EN; + + writel(tmp, dsi->regs + MCTL_MAIN_DATA_CTL); + + tmp = readl(dsi->regs + MCTL_MAIN_EN) | IF_EN(input->id); + writel(tmp, dsi->regs + MCTL_MAIN_EN); +} + +static const struct drm_bridge_funcs cdns_dsi_bridge_funcs = { + .attach = cdns_dsi_bridge_attach, + .mode_valid = cdns_dsi_bridge_mode_valid, + .disable = cdns_dsi_bridge_disable, + .enable = cdns_dsi_bridge_enable, +}; + +static int cdns_dsi_init_link(struct cdns_dsi *dsi) +{ + struct cdns_dsi_output *output = &dsi->output; + unsigned long sysclk_period, ulpout; + u32 val; + int i; + + writel(0, dsi->regs + MCTL_DPHY_STATIC); + + val = 0; + for (i = 1; i < output->dev->lanes; i++) + val |= DATA_LANE_EN(i); + + if (!(output->dev->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)) + val |= CLK_CONTINUOUS; + + writel(val, dsi->regs + MCTL_MAIN_PHY_CTL); + + /* ULPOUT should be set to 1ms and is expressed in sysclk cycles. */ + sysclk_period = NSEC_PER_SEC / clk_get_rate(dsi->sysclk); + ulpout = DIV_ROUND_UP(NSEC_PER_MSEC, sysclk_period); + writel(CLK_LANE_ULPOUT_TIME(ulpout) | DATA_LANE_ULPOUT_TIME(ulpout), + dsi->regs + MCTL_ULPOUT_TIME); + + writel(LINK_EN, dsi->regs + MCTL_MAIN_DATA_CTL); + + val = CLK_LANE_EN | PLL_START; + for (i = 0; i < output->dev->lanes; i++) + val |= DATA_LANE_START(i); + + writel(val, dsi->regs + MCTL_MAIN_EN); + + ndelay(100); + + return 0; +} + +static int cdns_dsi_attach(struct mipi_dsi_host *host, + struct mipi_dsi_device *dev) +{ + struct cdns_dsi *dsi = to_cdns_dsi(host); + struct cdns_dsi_output *output = &dsi->output; + struct cdns_dsi_input *input = &dsi->input; + struct drm_bridge *bridge; + struct drm_panel *panel; + struct device_node *np; + int ret; + + /* + * We currently do not support connecting several DSI devices to the + * same host. In order to support that we'd need the DRM bridge + * framework to allow dynamic reconfiguration of the bridge chain. + */ + if (output->dev) + return -EBUSY; + + /* We do not support burst mode yet. */ + if (dev->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) + return -ENOTSUPP; + + /* + * The host <-> device link might be described using an OF-graph + * representation, in this case we extract the device of_node from + * this representation, otherwise we use dsidev->dev.of_node which + * should have been filled by the core. + */ + np = of_graph_get_remote_node(dsi->base.dev->of_node, DSI_OUTPUT_PORT, + dev->channel); + if (!np) + np = of_node_get(dev->dev.of_node); + + panel = of_drm_find_panel(np); + if (panel) { + bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_DSI); + } else { + bridge = of_drm_find_bridge(dev->dev.of_node); + if (!bridge) + bridge = ERR_PTR(-EINVAL); + } + + of_node_put(np); + + if (IS_ERR(bridge)) { + ret = PTR_ERR(bridge); + dev_err(host->dev, "failed to add DSI device %s (err = %d)", + dev->name, ret); + return ret; + } + + output->dev = dev; + output->bridge = bridge; + output->panel = panel; + + ret = cdns_dsi_init_link(dsi); + if (ret) + goto err_rst_output; + + /* + * The DSI output has been properly configured, we can now safely + * register the input to the bridge framework so that it can take place + * in a display pipeline. + */ + drm_bridge_add(&input->bridge); + + return 0; + +err_rst_output: + if (panel) + drm_panel_bridge_remove(bridge); + + output->bridge = NULL; + output->panel = NULL; + output->dev = NULL; + + return ret; +} + +static int cdns_dsi_detach(struct mipi_dsi_host *host, + struct mipi_dsi_device *dev) +{ + struct cdns_dsi *dsi = to_cdns_dsi(host); + struct cdns_dsi_output *output = &dsi->output; + struct cdns_dsi_input *input = &dsi->input; + + drm_bridge_remove(&input->bridge); + if (output->panel) + drm_panel_bridge_remove(output->bridge); + + writel(0, dsi->regs + MCTL_MAIN_EN); + writel(0, dsi->regs + MCTL_MAIN_DATA_CTL); + writel(0, dsi->regs + MCTL_MAIN_PHY_CTL); + + return 0; +} + +static irqreturn_t cdns_dsi_interrupt(int irq, void *data) +{ + struct cdns_dsi *dsi = data; + irqreturn_t ret = IRQ_NONE; + u32 flag, ctl; + + flag = readl(dsi->regs + DIRECT_CMD_STS_FLAG); + if (flag) { + ctl = readl(dsi->regs + DIRECT_CMD_STS_CTL); + ctl &= ~flag; + writel(ctl, dsi->regs + DIRECT_CMD_STS_CTL); + complete(&dsi->direct_cmd_comp); + ret = IRQ_HANDLED; + } + + return ret; +} + +static ssize_t cdns_dsi_transfer(struct mipi_dsi_host *host, + const struct mipi_dsi_msg *msg) +{ + struct cdns_dsi *dsi = to_cdns_dsi(host); + u32 cmd, sts, val, wait = WRITE_COMPLETED, ctl = 0; + struct mipi_dsi_packet packet; + int ret, i, tx_len, rx_len; + + ret = mipi_dsi_create_packet(&packet, msg); + if (ret) + return ret; + + tx_len = msg->tx_buf ? msg->tx_len : 0; + rx_len = msg->rx_buf ? msg->rx_len : 0; + + /* For read operations, the maximum TX len is 2. */ + if (rx_len && tx_len > 2) + return -ENOTSUPP; + + /* TX len is limited by the CMD FIFO depth. */ + if (tx_len > dsi->direct_cmd_fifo_depth) + return -ENOTSUPP; + + /* RX len is limited by the RX FIFO depth. */ + if (rx_len > dsi->rx_fifo_depth) + return -ENOTSUPP; + + cmd = CMD_SIZE(tx_len) | CMD_VCHAN_ID(msg->channel) | + CMD_DATATYPE(msg->type); + + if (msg->flags & MIPI_DSI_MSG_USE_LPM) + cmd |= CMD_LP_EN; + + if (mipi_dsi_packet_format_is_long(msg->type)) + cmd |= CMD_LONG; + + if (rx_len) { + cmd |= READ_CMD; + wait = READ_COMPLETED_WITH_ERR | READ_COMPLETED; + ctl = READ_EN | BTA_EN; + } else if (msg->flags & MIPI_DSI_MSG_REQ_ACK) { + cmd |= BTA_REQ; + wait = ACK_WITH_ERR_RCVD | ACK_RCVD; + ctl = BTA_EN; + } + + writel(readl(dsi->regs + MCTL_MAIN_DATA_CTL) | ctl, + dsi->regs + MCTL_MAIN_DATA_CTL); + + writel(cmd, dsi->regs + DIRECT_CMD_MAIN_SETTINGS); + + for (i = 0; i < tx_len; i += 4) { + const u8 *buf = msg->tx_buf; + int j; + + val = 0; + for (j = 0; j < 4 && j + i < tx_len; j++) + val |= (u32)buf[i + j] << (8 * j); + + writel(val, dsi->regs + DIRECT_CMD_WRDATA); + } + + /* Clear status flags before sending the command. */ + writel(wait, dsi->regs + DIRECT_CMD_STS_CLR); + writel(wait, dsi->regs + DIRECT_CMD_STS_CTL); + reinit_completion(&dsi->direct_cmd_comp); + writel(0, dsi->regs + DIRECT_CMD_SEND); + + wait_for_completion_timeout(&dsi->direct_cmd_comp, + msecs_to_jiffies(1000)); + + sts = readl(dsi->regs + DIRECT_CMD_STS); + writel(wait, dsi->regs + DIRECT_CMD_STS_CLR); + writel(0, dsi->regs + DIRECT_CMD_STS_CTL); + + writel(readl(dsi->regs + MCTL_MAIN_DATA_CTL) & ~ctl, + dsi->regs + MCTL_MAIN_DATA_CTL); + + /* We did not receive the events we were waiting for. */ + if (!(sts & wait)) + return -ETIMEDOUT; + + /* READ of WRITE with ACK failed. */ + if (sts & (READ_COMPLETED_WITH_ERR | ACK_WITH_ERR_RCVD)) + return -EIO; + + for (i = 0; i < rx_len; i += 4) { + u8 *buf = msg->rx_buf; + int j; + + val = readl(dsi->regs + DIRECT_CMD_RDDATA); + for (j = 0; j < 4 && j + i < rx_len; j++) + buf[i + j] = val >> (8 * j); + } + + return 0; +} + +static const struct mipi_dsi_host_ops cdns_dsi_ops = { + .attach = cdns_dsi_attach, + .detach = cdns_dsi_detach, + .transfer = cdns_dsi_transfer, +}; + +static int cdns_dsi_drm_probe(struct platform_device *pdev) +{ + struct cdns_dsi *dsi; + struct cdns_dsi_input *input; + struct resource *res; + int ret, irq; + u32 val; + + dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL); + if (!dsi) + return -ENOMEM; + + input = &dsi->input; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + dsi->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(dsi->regs)) + return PTR_ERR(dsi->regs); + + dsi->pclk = devm_clk_get(&pdev->dev, "pclk"); + if (IS_ERR(dsi->pclk)) + return PTR_ERR(dsi->pclk); + + dsi->sysclk = devm_clk_get(&pdev->dev, "sysclk"); + if (IS_ERR(dsi->sysclk)) + return PTR_ERR(dsi->sysclk); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + ret = clk_prepare_enable(dsi->pclk); + if (ret) + return ret; + + ret = clk_prepare_enable(dsi->sysclk); + if (ret) + goto err_dis_pclk; + + val = readl(dsi->regs + ID_REG); + if (REV_VENDOR_ID(val) != 0xcad) { + dev_err(&pdev->dev, "invalid vendor id\n"); + return -EINVAL; + } + + val = readl(dsi->regs + IP_CONF); + dsi->direct_cmd_fifo_depth = 1 << (DIRCMD_FIFO_DEPTH(val) + 2); + dsi->rx_fifo_depth = RX_FIFO_DEPTH(val); + init_completion(&dsi->direct_cmd_comp); + + writel(0, dsi->regs + MCTL_MAIN_DATA_CTL); + writel(0, dsi->regs + MCTL_MAIN_EN); + writel(0, dsi->regs + MCTL_MAIN_PHY_CTL); + + /* + * We only support the DPI input, so force input->id to + * CDNS_DPI_INPUT. + */ + input->id = CDNS_DPI_INPUT; + input->bridge.funcs = &cdns_dsi_bridge_funcs; + input->bridge.of_node = pdev->dev.of_node; + + /* Mask all interrupts before registering the IRQ handler. */ + writel(0, dsi->regs + MCTL_MAIN_STS_CTL); + writel(0, dsi->regs + MCTL_DPHY_ERR_CTL1); + writel(0, dsi->regs + CMD_MODE_STS_CTL); + writel(0, dsi->regs + DIRECT_CMD_STS_CTL); + writel(0, dsi->regs + DIRECT_CMD_RD_STS_CTL); + writel(0, dsi->regs + VID_MODE_STS_CTL); + writel(0, dsi->regs + TVG_TBG_STS_CTL); + writel(0, dsi->regs + DPI_IRQ_EN); + ret = devm_request_irq(&pdev->dev, irq, cdns_dsi_interrupt, 0, + dev_name(&pdev->dev), dsi); + if (ret) + goto err_dis_sysclk; + + dsi->base.dev = &pdev->dev; + dsi->base.ops = &cdns_dsi_ops; + + ret = mipi_dsi_host_register(&dsi->base); + if (ret) + goto err_dis_sysclk; + + platform_set_drvdata(pdev, dsi); + + return 0; + +err_dis_sysclk: + clk_disable_unprepare(dsi->sysclk); + +err_dis_pclk: + clk_disable_unprepare(dsi->pclk); + + return ret; +} + +static int cdns_dsi_drm_remove(struct platform_device *pdev) +{ + struct cdns_dsi *dsi = platform_get_drvdata(pdev); + + mipi_dsi_host_unregister(&dsi->base); + clk_disable_unprepare(dsi->sysclk); + clk_disable_unprepare(dsi->pclk); + + return 0; +} + +static const struct of_device_id cdns_dsi_of_match[] = { + { .compatible = "cdns,dsi-1.3.1" }, + { }, +}; + +static struct platform_driver cdns_dsi_platform_driver = { + .probe = cdns_dsi_drm_probe, + .remove = cdns_dsi_drm_remove, + .driver = { + .name = "cdns-dsi", + .of_match_table = cdns_dsi_of_match, + }, +}; +module_platform_driver(cdns_dsi_platform_driver); + +MODULE_AUTHOR("Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Cadence DSI driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:cdns-dsi"); + -- 2.11.0 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
