[PATCH v4 06/13] drm/bridge: Add Synopsys DesignWare MIPI DSI host controller driver
From: Chris Zhong
Date: Fri Nov 20 2015 - 03:17:10 EST
add Synopsys DesignWare MIPI DSI host controller driver support.
Signed-off-by: Chris Zhong <zyw@xxxxxxxxxxxxxx>
---
Changes in v4:
eliminate some warnning
Changes in v3: None
Changes in v2: None
drivers/gpu/drm/bridge/Kconfig | 11 +
drivers/gpu/drm/bridge/Makefile | 1 +
drivers/gpu/drm/bridge/dw_mipi_dsi.c | 1056 ++++++++++++++++++++++++++++++++++
include/drm/bridge/dw_mipi_dsi.h | 27 +
4 files changed, 1095 insertions(+)
create mode 100644 drivers/gpu/drm/bridge/dw_mipi_dsi.c
create mode 100644 include/drm/bridge/dw_mipi_dsi.h
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index 6dddd39..c0900e0 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -22,6 +22,17 @@ config DRM_DW_HDMI_AHB_AUDIO
Designware HDMI block. This is used in conjunction with
the i.MX6 HDMI driver.
+config DRM_DW_MIPI_DSI
+ tristate "Synopsys DesignWare MIPI DSI host controller bridge"
+ depends on DRM
+ select DRM_KMS_HELPER
+ select DRM_MIPI_DSI
+ select DRM_PANEL
+ help
+ Choose this if you want to use the Synopsys DesignWare MIPI DSI host
+ controller bridge. If M is selected, the module will be
+ called dw_mipi_dsi. DRM_MIPI_DSI support is required for this driver
+ to work.
config DRM_NXP_PTN3460
tristate "NXP PTN3460 DP/LVDS bridge"
diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
index d4e28be..d908c4b 100644
--- a/drivers/gpu/drm/bridge/Makefile
+++ b/drivers/gpu/drm/bridge/Makefile
@@ -2,5 +2,6 @@ ccflags-y := -Iinclude/drm
obj-$(CONFIG_DRM_DW_HDMI) += dw_hdmi.o
obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw_hdmi-ahb-audio.o
+obj-$(CONFIG_DRM_DW_MIPI_DSI) += dw_mipi_dsi.o
obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
diff --git a/drivers/gpu/drm/bridge/dw_mipi_dsi.c b/drivers/gpu/drm/bridge/dw_mipi_dsi.c
new file mode 100644
index 0000000..23b612d
--- /dev/null
+++ b/drivers/gpu/drm/bridge/dw_mipi_dsi.c
@@ -0,0 +1,1056 @@
+/*
+ * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <drm/bridge/dw_mipi_dsi.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_panel.h>
+#include <video/mipi_display.h>
+
+#define DSI_VERSION 0x00
+
+#define DSI_PWR_UP 0x04
+#define RESET 0
+#define POWERUP BIT(0)
+
+#define DSI_CLKMGR_CFG 0x08
+#define TO_CLK_DIVIDSION(div) (((div) & 0xff) << 8)
+#define TX_ESC_CLK_DIVIDSION(div) (((div) & 0xff) << 0)
+
+#define DSI_DPI_VCID 0x0c
+#define DPI_VID(vid) (((vid) & 0x3) << 0)
+
+#define DSI_DPI_COLOR_CODING 0x10
+#define EN18_LOOSELY BIT(8)
+#define DPI_COLOR_CODING_16BIT_1 0x0
+#define DPI_COLOR_CODING_16BIT_2 0x1
+#define DPI_COLOR_CODING_16BIT_3 0x2
+#define DPI_COLOR_CODING_18BIT_1 0x3
+#define DPI_COLOR_CODING_18BIT_2 0x4
+#define DPI_COLOR_CODING_24BIT 0x5
+
+#define DSI_DPI_CFG_POL 0x14
+#define COLORM_ACTIVE_LOW BIT(4)
+#define SHUTD_ACTIVE_LOW BIT(3)
+#define HSYNC_ACTIVE_LOW BIT(2)
+#define VSYNC_ACTIVE_LOW BIT(1)
+#define DATAEN_ACTIVE_LOW BIT(0)
+
+#define DSI_DPI_LP_CMD_TIM 0x18
+#define OUTVACT_LPCMD_TIME(p) (((p) & 0xff) << 16)
+#define INVACT_LPCMD_TIME(p) ((p) & 0xff)
+
+#define DSI_DBI_CFG 0x20
+#define DSI_DBI_CMDSIZE 0x28
+
+#define DSI_PCKHDL_CFG 0x2c
+#define EN_CRC_RX BIT(4)
+#define EN_ECC_RX BIT(3)
+#define EN_BTA BIT(2)
+#define EN_EOTP_RX BIT(1)
+#define EN_EOTP_TX BIT(0)
+
+#define DSI_MODE_CFG 0x34
+#define ENABLE_VIDEO_MODE 0
+#define ENABLE_CMD_MODE BIT(0)
+
+#define DSI_VID_MODE_CFG 0x38
+#define FRAME_BTA_ACK BIT(14)
+#define ENABLE_LOW_POWER (0x3f << 8)
+#define ENABLE_LOW_POWER_MASK (0x3f << 8)
+#define VID_MODE_TYPE_BURST_SYNC_PULSES 0x2
+#define VID_MODE_TYPE_MASK 0x3
+
+#define DSI_VID_PKT_SIZE 0x3c
+#define VID_PKT_SIZE(p) (((p) & 0x3fff) << 0)
+#define VID_PKT_MAX_SIZE 0x3fff
+
+#define DSI_VID_HSA_TIME 0x48
+#define DSI_VID_HBP_TIME 0x4c
+#define DSI_VID_HLINE_TIME 0x50
+#define DSI_VID_VSA_LINES 0x54
+#define DSI_VID_VBP_LINES 0x58
+#define DSI_VID_VFP_LINES 0x5c
+#define DSI_VID_VACTIVE_LINES 0x60
+#define DSI_CMD_MODE_CFG 0x68
+#define MAX_RD_PKT_SIZE_LP BIT(24)
+#define DCS_LW_TX_LP BIT(19)
+#define DCS_SR_0P_TX_LP BIT(18)
+#define DCS_SW_1P_TX_LP BIT(17)
+#define DCS_SW_0P_TX_LP BIT(16)
+#define GEN_LW_TX_LP BIT(14)
+#define GEN_SR_2P_TX_LP BIT(13)
+#define GEN_SR_1P_TX_LP BIT(12)
+#define GEN_SR_0P_TX_LP BIT(11)
+#define GEN_SW_2P_TX_LP BIT(10)
+#define GEN_SW_1P_TX_LP BIT(9)
+#define GEN_SW_0P_TX_LP BIT(8)
+#define EN_ACK_RQST BIT(1)
+#define EN_TEAR_FX BIT(0)
+
+#define CMD_MODE_ALL_LP (MAX_RD_PKT_SIZE_LP | \
+ DCS_LW_TX_LP | \
+ DCS_SR_0P_TX_LP | \
+ DCS_SW_1P_TX_LP | \
+ DCS_SW_0P_TX_LP | \
+ GEN_LW_TX_LP | \
+ GEN_SR_2P_TX_LP | \
+ GEN_SR_1P_TX_LP | \
+ GEN_SR_0P_TX_LP | \
+ GEN_SW_2P_TX_LP | \
+ GEN_SW_1P_TX_LP | \
+ GEN_SW_0P_TX_LP)
+
+#define DSI_GEN_HDR 0x6c
+#define GEN_HDATA(data) (((data) & 0xffff) << 8)
+#define GEN_HDATA_MASK (0xffff << 8)
+#define GEN_HTYPE(type) (((type) & 0xff) << 0)
+#define GEN_HTYPE_MASK 0xff
+
+#define DSI_GEN_PLD_DATA 0x70
+
+#define DSI_CMD_PKT_STATUS 0x74
+#define GEN_CMD_EMPTY BIT(0)
+#define GEN_CMD_FULL BIT(1)
+#define GEN_PLD_W_EMPTY BIT(2)
+#define GEN_PLD_W_FULL BIT(3)
+#define GEN_PLD_R_EMPTY BIT(4)
+#define GEN_PLD_R_FULL BIT(5)
+#define GEN_RD_CMD_BUSY BIT(6)
+
+#define DSI_TO_CNT_CFG 0x78
+#define HSTX_TO_CNT(p) (((p) & 0xffff) << 16)
+#define LPRX_TO_CNT(p) ((p) & 0xffff)
+
+#define DSI_BTA_TO_CNT 0x8c
+
+#define DSI_LPCLK_CTRL 0x94
+#define AUTO_CLKLANE_CTRL BIT(1)
+#define PHY_TXREQUESTCLKHS BIT(0)
+
+#define DSI_PHY_TMR_LPCLK_CFG 0x98
+#define PHY_CLKHS2LP_TIME(lbcc) (((lbcc) & 0x3ff) << 16)
+#define PHY_CLKLP2HS_TIME(lbcc) ((lbcc) & 0x3ff)
+
+#define DSI_PHY_TMR_CFG 0x9c
+#define PHY_HS2LP_TIME(lbcc) (((lbcc) & 0xff) << 24)
+#define PHY_LP2HS_TIME(lbcc) (((lbcc) & 0xff) << 16)
+#define MAX_RD_TIME(lbcc) ((lbcc) & 0x7fff)
+
+#define DSI_PHY_RSTZ 0xa0
+#define PHY_DISFORCEPLL 0
+#define PHY_ENFORCEPLL BIT(3)
+#define PHY_DISABLECLK 0
+#define PHY_ENABLECLK BIT(2)
+#define PHY_RSTZ 0
+#define PHY_UNRSTZ BIT(1)
+#define PHY_SHUTDOWNZ 0
+#define PHY_UNSHUTDOWNZ BIT(0)
+
+#define DSI_PHY_IF_CFG 0xa4
+#define N_LANES(n) ((((n) - 1) & 0x3) << 0)
+#define PHY_STOP_WAIT_TIME(cycle) (((cycle) & 0xff) << 8)
+
+#define DSI_PHY_STATUS 0xb0
+#define LOCK BIT(0)
+#define STOP_STATE_CLK_LANE BIT(2)
+
+#define DSI_PHY_TST_CTRL0 0xb4
+#define PHY_TESTCLK BIT(1)
+#define PHY_UNTESTCLK 0
+#define PHY_TESTCLR BIT(0)
+#define PHY_UNTESTCLR 0
+
+#define DSI_PHY_TST_CTRL1 0xb8
+#define PHY_TESTEN BIT(16)
+#define PHY_UNTESTEN 0
+#define PHY_TESTDOUT(n) (((n) & 0xff) << 8)
+#define PHY_TESTDIN(n) (((n) & 0xff) << 0)
+
+#define DSI_INT_ST0 0xbc
+#define DSI_INT_ST1 0xc0
+#define DSI_INT_MSK0 0xc4
+#define DSI_INT_MSK1 0xc8
+
+#define PHY_STATUS_TIMEOUT 10
+#define CMD_PKT_STATUS_TIMEOUT 20
+
+struct dw_mipi_dsi {
+ struct mipi_dsi_host dsi_host;
+ struct drm_connector connector;
+ struct drm_encoder *encoder;
+ struct drm_bridge *bridge;
+ struct drm_panel *panel;
+ struct device *dev;
+
+ void __iomem *base;
+
+ struct clk *pllref_clk;
+ struct clk *cfg_clk;
+ struct clk *pclk;
+
+ unsigned int lane_mbps; /* per lane */
+ u32 channel;
+ u32 lanes;
+ u32 format;
+ u16 input_div;
+ u16 feedback_div;
+ struct drm_display_mode *mode;
+
+ const struct dw_mipi_dsi_plat_data *pdata;
+
+ bool enabled;
+};
+
+enum {
+ STATUS_TO_CLEAR,
+ STATUS_TO_SET,
+};
+
+enum dw_mipi_dsi_mode {
+ DW_MIPI_DSI_CMD_MODE,
+ DW_MIPI_DSI_VID_MODE,
+};
+
+struct dphy_pll_testdin_map {
+ unsigned int max_mbps;
+ u8 testdin;
+};
+
+/* The table is based on 27MHz DPHY pll reference clock. */
+static const struct dphy_pll_testdin_map dptdin_map[] = {
+ {90, 0x00}, {100, 0x10}, {110, 0x20}, {130, 0x01},
+ {140, 0x11}, {150, 0x21}, {170, 0x02}, {180, 0x12},
+ {200, 0x22}, {220, 0x03}, {240, 0x13}, {250, 0x23},
+ {270, 0x04}, {300, 0x14}, {330, 0x05}, {360, 0x15},
+ {400, 0x25}, {450, 0x06}, {500, 0x16}, {550, 0x07},
+ {600, 0x17}, {650, 0x08}, {700, 0x18}, {750, 0x09},
+ {800, 0x19}, {850, 0x29}, {900, 0x39}, {950, 0x0a},
+ {1000, 0x1a}, {1050, 0x2a}, {1100, 0x3a}, {1150, 0x0b},
+ {1200, 0x1b}, {1250, 0x2b}, {1300, 0x3b}, {1350, 0x0c},
+ {1400, 0x1c}, {1450, 0x2c}, {1500, 0x3c}
+};
+
+static inline struct dw_mipi_dsi *host_to_dsi(struct mipi_dsi_host *host)
+{
+ return container_of(host, struct dw_mipi_dsi, dsi_host);
+}
+
+static inline struct dw_mipi_dsi *con_to_dsi(struct drm_connector *con)
+{
+ return container_of(con, struct dw_mipi_dsi, connector);
+}
+
+int dw_mipi_dsi_get_encoder_pixel_format(struct drm_encoder *encoder)
+{
+ struct dw_mipi_dsi *dsi = encoder->bridge->driver_private;
+
+ return dsi->format;
+}
+EXPORT_SYMBOL_GPL(dw_mipi_dsi_get_encoder_pixel_format);
+
+static int max_mbps_to_testdin(unsigned int max_mbps)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(dptdin_map); i++)
+ if (dptdin_map[i].max_mbps > max_mbps)
+ return dptdin_map[i].testdin;
+
+ return -EINVAL;
+}
+
+static inline void dsi_write(struct dw_mipi_dsi *dsi, u32 reg, u32 val)
+{
+ writel(val, dsi->base + reg);
+}
+
+static inline u32 dsi_read(struct dw_mipi_dsi *dsi, u32 reg)
+{
+ return readl(dsi->base + reg);
+}
+
+static inline void dsi_modify(struct dw_mipi_dsi *dsi, u32 reg,
+ u32 mask, u32 val)
+{
+ u32 v;
+
+ v = readl(dsi->base + reg);
+ v &= ~mask;
+ v |= val;
+ writel(v, dsi->base + reg);
+}
+
+static int check_status(struct dw_mipi_dsi *dsi, u32 reg, u32 status,
+ unsigned int timeout, bool to_set)
+{
+ unsigned long expire;
+ bool out;
+ u32 val;
+
+ expire = jiffies + msecs_to_jiffies(timeout);
+ for (;;) {
+ val = dsi_read(dsi, reg);
+ out = to_set ? ((val & status) == status) : !(val & status);
+ if (out)
+ break;
+
+ if (time_after(jiffies, expire))
+ return -ETIMEDOUT;
+
+ cpu_relax();
+ }
+
+ return 0;
+}
+
+/*
+ * The controller should generate 2 frames before
+ * preparing the peripheral.
+ */
+static void dw_mipi_dsi_wait_for_two_frames(struct dw_mipi_dsi *dsi)
+{
+ unsigned long expire;
+ int refresh, two_frames;
+
+ refresh = drm_mode_vrefresh(dsi->mode);
+ two_frames = DIV_ROUND_UP(MSEC_PER_SEC, refresh) * 2;
+
+ expire = jiffies + msecs_to_jiffies(two_frames);
+ while (time_before(jiffies, expire))
+ cpu_relax();
+}
+
+static void dw_mipi_dsi_phy_test(struct dw_mipi_dsi *dsi, u8 test_code,
+ u8 test_data)
+{
+ dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLK | PHY_UNTESTCLR);
+
+ dsi_write(dsi, DSI_PHY_TST_CTRL1, PHY_TESTEN | PHY_TESTDOUT(0) |
+ PHY_TESTDIN(test_code));
+
+ dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_TESTCLK | PHY_UNTESTCLR);
+ dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLK | PHY_UNTESTCLR);
+
+ dsi_write(dsi, DSI_PHY_TST_CTRL1, PHY_UNTESTEN | PHY_TESTDOUT(0) |
+ PHY_TESTDIN(test_data));
+
+ dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_TESTCLK | PHY_UNTESTCLR);
+ dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLK | PHY_UNTESTCLR);
+}
+
+static int dw_mipi_dsi_phy_init(struct dw_mipi_dsi *dsi)
+{
+ int ret, testdin, vco;
+
+ vco = (dsi->lane_mbps < 200) ? 0 : (dsi->lane_mbps + 100) / 200;
+
+ testdin = max_mbps_to_testdin(dsi->lane_mbps);
+ if (testdin < 0) {
+ dev_err(dsi->dev,
+ "failed to get testdin for %dmbps lane clock\n",
+ dsi->lane_mbps);
+ return testdin;
+ }
+
+ dsi_write(dsi, DSI_PWR_UP, POWERUP);
+
+ dw_mipi_dsi_phy_test(dsi, 0x10, 0x80 | (vco & 0x7) << 3 | 0x3);
+ dw_mipi_dsi_phy_test(dsi, 0x11, 0x8);
+ dw_mipi_dsi_phy_test(dsi, 0x12, 0xc0);
+
+ dw_mipi_dsi_phy_test(dsi, 0x44, testdin << 1);
+
+ dw_mipi_dsi_phy_test(dsi, 0x17, dsi->input_div - 1);
+ dw_mipi_dsi_phy_test(dsi, 0x18, (dsi->feedback_div - 1) & 0x1f);
+ dw_mipi_dsi_phy_test(dsi, 0x18, (dsi->feedback_div - 1) >> 5 | 0x80);
+ dw_mipi_dsi_phy_test(dsi, 0x19, 0x30);
+
+ dw_mipi_dsi_phy_test(dsi, 0x20, 0x4d);
+ dw_mipi_dsi_phy_test(dsi, 0x21, 0x3d);
+ dw_mipi_dsi_phy_test(dsi, 0x21, 0xdf);
+ dw_mipi_dsi_phy_test(dsi, 0x22, 0x7);
+ dw_mipi_dsi_phy_test(dsi, 0x22, 0x87);
+ dw_mipi_dsi_phy_test(dsi, 0x70, 0x80 | 0xf);
+ dw_mipi_dsi_phy_test(dsi, 0x71, 0x80 | 0x55);
+ dw_mipi_dsi_phy_test(dsi, 0x72, 0x40 | 0xa);
+
+ dsi_write(dsi, DSI_PHY_RSTZ, PHY_ENFORCEPLL | PHY_ENABLECLK
+ | PHY_UNRSTZ | PHY_UNSHUTDOWNZ);
+
+ ret = check_status(dsi, DSI_PHY_STATUS, LOCK,
+ PHY_STATUS_TIMEOUT, STATUS_TO_SET);
+ if (ret < 0) {
+ dev_err(dsi->dev, "failed to wait for phy lock state\n");
+ return ret;
+ }
+ ret = check_status(dsi, DSI_PHY_STATUS, STOP_STATE_CLK_LANE,
+ PHY_STATUS_TIMEOUT, STATUS_TO_SET);
+ if (ret < 0) {
+ dev_err(dsi->dev,
+ "failed to wait for phy clk lane stop state\n");
+ return ret;
+ }
+
+ return ret;
+}
+
+static int dw_mipi_dsi_get_lane_bps(struct dw_mipi_dsi *dsi)
+{
+ int bpp, i;
+ unsigned int max_mbps = 0, target_mbps = 1000;
+ unsigned long mpclk, pllref, tmp;
+ int m = 1, n = 1, pre;
+
+ for (i = 0; i < ARRAY_SIZE(dptdin_map); i++) {
+ if (max_mbps < dptdin_map[i].max_mbps)
+ max_mbps = dptdin_map[i].max_mbps;
+ }
+
+ bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
+ if (bpp < 0) {
+ dev_err(dsi->dev, "failed to get bpp for pixel format %d\n",
+ dsi->format);
+ return bpp;
+ }
+
+ mpclk = DIV_ROUND_UP(dsi->mode->clock, MSEC_PER_SEC);
+ if (mpclk) {
+ /* take 1 / 0.9, since mbps must big than bandwidth of RGB */
+ tmp = mpclk * (bpp / dsi->lanes) * 10 / 9;
+ if (tmp < max_mbps)
+ target_mbps = tmp;
+ else
+ dev_err(dsi->dev, "DPHY clock frequency is out of range\n");
+ }
+
+ pllref = DIV_ROUND_UP(clk_get_rate(dsi->pllref_clk), USEC_PER_SEC);
+ tmp = pllref;
+
+ for (i = 1; i < 6; i++) {
+ pre = pllref / i;
+ if ((tmp > (target_mbps % pre)) && (target_mbps / pre < 512)) {
+ tmp = target_mbps % pre;
+ n = i;
+ m = target_mbps / pre;
+ }
+ if (tmp == 0)
+ break;
+ }
+
+ dsi->lane_mbps = pllref / n * m;
+ dsi->input_div = n;
+ dsi->feedback_div = m;
+
+ return 0;
+}
+
+static int dw_mipi_dsi_host_attach(struct mipi_dsi_host *host,
+ struct mipi_dsi_device *device)
+{
+ struct dw_mipi_dsi *dsi = host_to_dsi(host);
+
+ if (device->lanes > dsi->pdata->max_data_lanes) {
+ dev_err(dsi->dev, "the number of data lanes(%d) is too many\n",
+ device->lanes);
+ return -EINVAL;
+ }
+
+ if (!(device->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) ||
+ !(device->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)) {
+ dev_err(dsi->dev, "device mode is unsupported\n");
+ return -EINVAL;
+ }
+
+ dsi->lanes = device->lanes;
+ dsi->channel = device->channel;
+ dsi->format = device->format;
+ dsi->panel = of_drm_find_panel(device->dev.of_node);
+ drm_panel_attach(dsi->panel, &dsi->connector);
+
+ return 0;
+}
+
+static int dw_mipi_dsi_host_detach(struct mipi_dsi_host *host,
+ struct mipi_dsi_device *device)
+{
+ struct dw_mipi_dsi *dsi = host_to_dsi(host);
+
+ drm_panel_detach(dsi->panel);
+
+ return 0;
+}
+
+static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 val)
+{
+ int ret;
+
+ ret = check_status(dsi, DSI_CMD_PKT_STATUS, GEN_CMD_FULL,
+ CMD_PKT_STATUS_TIMEOUT, STATUS_TO_CLEAR);
+ if (ret < 0) {
+ dev_err(dsi->dev, "failed to get available command FIFO\n");
+ return ret;
+ }
+
+ dsi_write(dsi, DSI_GEN_HDR, val);
+
+ ret = check_status(dsi, DSI_CMD_PKT_STATUS,
+ GEN_CMD_EMPTY | GEN_PLD_W_EMPTY,
+ CMD_PKT_STATUS_TIMEOUT, STATUS_TO_SET);
+ if (ret < 0) {
+ dev_err(dsi->dev, "failed to write command FIFO\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int dw_mipi_dsi_dcs_short_write(struct dw_mipi_dsi *dsi,
+ const struct mipi_dsi_msg *msg)
+{
+ const u16 *tx_buf = msg->tx_buf;
+ u32 val = GEN_HDATA(*tx_buf) | GEN_HTYPE(msg->type);
+
+ if (msg->tx_len > 2) {
+ dev_err(dsi->dev, "too long tx buf length %d for short write\n",
+ (int)msg->tx_len);
+ return -EINVAL;
+ }
+
+ return dw_mipi_dsi_gen_pkt_hdr_write(dsi, val);
+}
+
+static int dw_mipi_dsi_dcs_long_write(struct dw_mipi_dsi *dsi,
+ const struct mipi_dsi_msg *msg)
+{
+ const u32 *tx_buf = msg->tx_buf;
+ int len = msg->tx_len, pld_data_bytes = sizeof(*tx_buf), ret;
+ u32 val = GEN_HDATA(msg->tx_len) | GEN_HTYPE(msg->type);
+ u32 remainder = 0;
+
+ if (msg->tx_len < 3) {
+ dev_err(dsi->dev, "wrong tx buf length %d for long write\n",
+ (int)msg->tx_len);
+ return -EINVAL;
+ }
+
+ while (DIV_ROUND_UP(len, pld_data_bytes)) {
+ if (len < pld_data_bytes) {
+ memcpy(&remainder, tx_buf, len);
+ dsi_write(dsi, DSI_GEN_PLD_DATA, remainder);
+ len = 0;
+ } else {
+ dsi_write(dsi, DSI_GEN_PLD_DATA, *tx_buf);
+ tx_buf++;
+ len -= pld_data_bytes;
+ }
+ ret = check_status(dsi, DSI_CMD_PKT_STATUS, GEN_PLD_W_FULL,
+ CMD_PKT_STATUS_TIMEOUT, STATUS_TO_CLEAR);
+ if (ret < 0) {
+ dev_err(dsi->dev,
+ "failed to get available write payload FIFO\n");
+ return ret;
+ }
+ }
+
+ return dw_mipi_dsi_gen_pkt_hdr_write(dsi, val);
+}
+
+static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
+ const struct mipi_dsi_msg *msg)
+{
+ struct dw_mipi_dsi *dsi = host_to_dsi(host);
+ int ret;
+
+ switch (msg->type) {
+ case MIPI_DSI_DCS_SHORT_WRITE:
+ case MIPI_DSI_DCS_SHORT_WRITE_PARAM:
+ case MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE:
+ ret = dw_mipi_dsi_dcs_short_write(dsi, msg);
+ break;
+ case MIPI_DSI_DCS_LONG_WRITE:
+ ret = dw_mipi_dsi_dcs_long_write(dsi, msg);
+ break;
+ default:
+ dev_err(dsi->dev, "unsupported message type\n");
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+static const struct mipi_dsi_host_ops dw_mipi_dsi_host_ops = {
+ .attach = dw_mipi_dsi_host_attach,
+ .detach = dw_mipi_dsi_host_detach,
+ .transfer = dw_mipi_dsi_host_transfer,
+};
+
+static enum drm_connector_status
+dw_mipi_dsi_detect(struct drm_connector *connector, bool force)
+{
+ return connector_status_connected;
+}
+
+static void dw_mipi_dsi_drm_connector_destroy(struct drm_connector *connector)
+{
+ drm_connector_unregister(connector);
+ drm_connector_cleanup(connector);
+}
+
+static struct drm_connector_funcs dw_mipi_dsi_connector_funcs = {
+ .dpms = drm_helper_connector_dpms,
+ .fill_modes = drm_helper_probe_single_connector_modes,
+ .detect = dw_mipi_dsi_detect,
+ .destroy = dw_mipi_dsi_drm_connector_destroy,
+};
+
+static int dw_mipi_dsi_connector_get_modes(struct drm_connector *connector)
+{
+ struct dw_mipi_dsi *dsi = con_to_dsi(connector);
+
+ return drm_panel_get_modes(dsi->panel);
+}
+
+static enum drm_mode_status dw_mipi_dsi_mode_valid(
+ struct drm_connector *connector,
+ struct drm_display_mode *mode)
+{
+ struct dw_mipi_dsi *dsi = con_to_dsi(connector);
+
+ enum drm_mode_status mode_status = MODE_OK;
+
+ if (dsi->pdata->mode_valid)
+ mode_status = dsi->pdata->mode_valid(connector, mode);
+
+ return mode_status;
+}
+
+static struct drm_encoder *dw_mipi_dsi_connector_best_encoder(
+ struct drm_connector *connector)
+{
+ struct dw_mipi_dsi *dsi = con_to_dsi(connector);
+
+ return dsi->encoder;
+}
+
+static struct drm_connector_helper_funcs dw_mipi_dsi_connector_helper_funcs = {
+ .get_modes = dw_mipi_dsi_connector_get_modes,
+ .mode_valid = dw_mipi_dsi_mode_valid,
+ .best_encoder = dw_mipi_dsi_connector_best_encoder,
+};
+
+static void dw_mipi_dsi_video_mode_config(struct dw_mipi_dsi *dsi)
+{
+ u32 val;
+
+ val = VID_MODE_TYPE_BURST_SYNC_PULSES | ENABLE_LOW_POWER;
+
+ dsi_write(dsi, DSI_VID_MODE_CFG, val);
+}
+
+static void dw_mipi_dsi_set_mode(struct dw_mipi_dsi *dsi,
+ enum dw_mipi_dsi_mode mode)
+{
+ if (mode == DW_MIPI_DSI_CMD_MODE) {
+ dsi_write(dsi, DSI_PWR_UP, RESET);
+ dsi_write(dsi, DSI_MODE_CFG, ENABLE_CMD_MODE);
+ dsi_write(dsi, DSI_PWR_UP, POWERUP);
+ } else {
+ dsi_write(dsi, DSI_PWR_UP, RESET);
+ dsi_write(dsi, DSI_MODE_CFG, ENABLE_VIDEO_MODE);
+ dw_mipi_dsi_video_mode_config(dsi);
+ dsi_write(dsi, DSI_PWR_UP, POWERUP);
+ }
+}
+
+static void dw_mipi_dsi_disable(struct dw_mipi_dsi *dsi)
+{
+ dsi_write(dsi, DSI_PWR_UP, RESET);
+ dsi_write(dsi, DSI_PHY_RSTZ, PHY_RSTZ);
+}
+
+static void dw_mipi_dsi_bridge_enable(struct drm_bridge *bridge)
+{
+ struct dw_mipi_dsi *dsi = bridge->driver_private;
+
+ if (dsi->enabled)
+ return;
+
+ if (!IS_ERR(dsi->cfg_clk))
+ clk_prepare_enable(dsi->cfg_clk);
+
+ clk_prepare_enable(dsi->pclk);
+ dw_mipi_dsi_phy_init(dsi);
+ dw_mipi_dsi_set_mode(dsi, DW_MIPI_DSI_VID_MODE);
+ dw_mipi_dsi_wait_for_two_frames(dsi);
+ dw_mipi_dsi_set_mode(dsi, DW_MIPI_DSI_CMD_MODE);
+ drm_panel_prepare(dsi->panel);
+ dw_mipi_dsi_set_mode(dsi, DW_MIPI_DSI_VID_MODE);
+ clk_disable_unprepare(dsi->pclk);
+
+ if (!IS_ERR(dsi->cfg_clk))
+ clk_disable_unprepare(dsi->cfg_clk);
+
+ drm_panel_enable(dsi->panel);
+
+ dsi->enabled = true;
+}
+
+static void dw_mipi_dsi_bridge_disable(struct drm_bridge *bridge)
+{
+ struct dw_mipi_dsi *dsi = bridge->driver_private;
+ unsigned long expire;
+
+ if (!dsi->enabled)
+ return;
+
+ drm_panel_disable(dsi->panel);
+
+ if (!IS_ERR(dsi->cfg_clk))
+ clk_prepare_enable(dsi->cfg_clk);
+
+ clk_prepare_enable(dsi->pclk);
+ dw_mipi_dsi_set_mode(dsi, DW_MIPI_DSI_CMD_MODE);
+ drm_panel_unprepare(dsi->panel);
+ dw_mipi_dsi_set_mode(dsi, DW_MIPI_DSI_VID_MODE);
+
+ /*
+ * This is necessary to make sure the peripheral
+ * will be driven normally when the display is
+ * enabled again later.
+ */
+ expire = jiffies + msecs_to_jiffies(120);
+ while (time_before(jiffies, expire))
+ cpu_relax();
+
+ dw_mipi_dsi_set_mode(dsi, DW_MIPI_DSI_CMD_MODE);
+ dw_mipi_dsi_disable(dsi);
+ clk_disable_unprepare(dsi->pclk);
+
+ if (!IS_ERR(dsi->cfg_clk))
+ clk_disable_unprepare(dsi->cfg_clk);
+
+ dsi->enabled = false;
+}
+
+static void dw_mipi_dsi_bridge_nope(struct drm_bridge *bridge)
+{
+ /* do nothing */
+}
+
+static void dw_mipi_dsi_init(struct dw_mipi_dsi *dsi)
+{
+ dsi_write(dsi, DSI_PWR_UP, RESET);
+ dsi_write(dsi, DSI_PHY_RSTZ, PHY_DISFORCEPLL | PHY_DISABLECLK
+ | PHY_RSTZ | PHY_SHUTDOWNZ);
+ dsi_write(dsi, DSI_CLKMGR_CFG, TO_CLK_DIVIDSION(10) |
+ TX_ESC_CLK_DIVIDSION(7));
+ dsi_write(dsi, DSI_LPCLK_CTRL, PHY_TXREQUESTCLKHS);
+}
+
+static void dw_mipi_dsi_dpi_config(struct dw_mipi_dsi *dsi,
+ struct drm_display_mode *mode)
+{
+ u32 val = 0, calor = 0;
+
+ switch (dsi->format) {
+ case MIPI_DSI_FMT_RGB888:
+ calor = DPI_COLOR_CODING_24BIT;
+ break;
+ case MIPI_DSI_FMT_RGB666:
+ calor = DPI_COLOR_CODING_18BIT_2 | EN18_LOOSELY;
+ break;
+ case MIPI_DSI_FMT_RGB666_PACKED:
+ calor = DPI_COLOR_CODING_18BIT_1;
+ break;
+ case MIPI_DSI_FMT_RGB565:
+ calor = DPI_COLOR_CODING_16BIT_1;
+ break;
+ }
+
+ if (!(mode->flags & DRM_MODE_FLAG_PVSYNC))
+ val |= VSYNC_ACTIVE_LOW;
+ if (!(mode->flags & DRM_MODE_FLAG_PHSYNC))
+ val |= HSYNC_ACTIVE_LOW;
+
+ dsi_write(dsi, DSI_DPI_VCID, DPI_VID(dsi->channel));
+ dsi_write(dsi, DSI_DPI_COLOR_CODING, calor);
+ dsi_write(dsi, DSI_DPI_CFG_POL, val);
+ dsi_write(dsi, DSI_DPI_LP_CMD_TIM, OUTVACT_LPCMD_TIME(4)
+ | INVACT_LPCMD_TIME(4));
+}
+
+static void dw_mipi_dsi_packet_handler_config(struct dw_mipi_dsi *dsi)
+{
+ dsi_write(dsi, DSI_PCKHDL_CFG, EN_CRC_RX | EN_ECC_RX | EN_BTA);
+}
+
+static void dw_mipi_dsi_video_packet_config(struct dw_mipi_dsi *dsi,
+ struct drm_display_mode *mode)
+{
+ dsi_write(dsi, DSI_VID_PKT_SIZE, VID_PKT_SIZE(mode->hdisplay));
+}
+
+static void dw_mipi_dsi_command_mode_config(struct dw_mipi_dsi *dsi)
+{
+ dsi_write(dsi, DSI_TO_CNT_CFG, HSTX_TO_CNT(1000) | LPRX_TO_CNT(1000));
+ dsi_write(dsi, DSI_BTA_TO_CNT, 0xd00);
+ dsi_write(dsi, DSI_CMD_MODE_CFG, CMD_MODE_ALL_LP);
+ dsi_write(dsi, DSI_MODE_CFG, ENABLE_CMD_MODE);
+}
+
+/* Get lane byte clock cycles. */
+static u32 dw_mipi_dsi_get_hcomponent_lbcc(struct dw_mipi_dsi *dsi,
+ u32 hcomponent)
+{
+ u32 frac, lbcc;
+
+ lbcc = hcomponent * dsi->lane_mbps * MSEC_PER_SEC / 8;
+
+ frac = lbcc % dsi->mode->clock;
+ lbcc = lbcc / dsi->mode->clock;
+ if (frac)
+ lbcc++;
+
+ return lbcc;
+}
+
+static void dw_mipi_dsi_line_timer_config(struct dw_mipi_dsi *dsi)
+{
+ u32 htotal, hsa, hbp, lbcc;
+ struct drm_display_mode *mode = dsi->mode;
+
+ htotal = mode->htotal;
+ hsa = mode->hsync_end - mode->hsync_start;
+ hbp = mode->htotal - mode->hsync_end;
+
+ lbcc = dw_mipi_dsi_get_hcomponent_lbcc(dsi, htotal);
+ dsi_write(dsi, DSI_VID_HLINE_TIME, lbcc);
+
+ lbcc = dw_mipi_dsi_get_hcomponent_lbcc(dsi, hsa);
+ dsi_write(dsi, DSI_VID_HSA_TIME, lbcc);
+
+ lbcc = dw_mipi_dsi_get_hcomponent_lbcc(dsi, hbp);
+ dsi_write(dsi, DSI_VID_HBP_TIME, lbcc);
+}
+
+static void dw_mipi_dsi_vertical_timing_config(struct dw_mipi_dsi *dsi)
+{
+ u32 vactive, vsa, vfp, vbp;
+ struct drm_display_mode *mode = dsi->mode;
+
+ vactive = mode->vdisplay;
+ vsa = mode->vsync_end - mode->vsync_start;
+ vfp = mode->vsync_start - mode->vdisplay;
+ vbp = mode->vtotal - mode->vsync_end;
+
+ dsi_write(dsi, DSI_VID_VACTIVE_LINES, vactive);
+ dsi_write(dsi, DSI_VID_VSA_LINES, vsa);
+ dsi_write(dsi, DSI_VID_VFP_LINES, vfp);
+ dsi_write(dsi, DSI_VID_VBP_LINES, vbp);
+}
+
+static void dw_mipi_dsi_dphy_timing_config(struct dw_mipi_dsi *dsi)
+{
+ dsi_write(dsi, DSI_PHY_TMR_CFG, PHY_HS2LP_TIME(0x40)
+ | PHY_LP2HS_TIME(0x40) | MAX_RD_TIME(10000));
+
+ dsi_write(dsi, DSI_PHY_TMR_LPCLK_CFG, PHY_CLKHS2LP_TIME(0x40)
+ | PHY_CLKLP2HS_TIME(0x40));
+}
+
+static void dw_mipi_dsi_dphy_interface_config(struct dw_mipi_dsi *dsi)
+{
+ dsi_write(dsi, DSI_PHY_IF_CFG, PHY_STOP_WAIT_TIME(0x20) |
+ N_LANES(dsi->lanes));
+}
+
+static void dw_mipi_dsi_clear_err(struct dw_mipi_dsi *dsi)
+{
+ dsi_read(dsi, DSI_INT_ST0);
+ dsi_read(dsi, DSI_INT_ST1);
+ dsi_write(dsi, DSI_INT_MSK0, 0);
+ dsi_write(dsi, DSI_INT_MSK1, 0);
+}
+
+static void dw_mipi_dsi_bridge_mode_set(struct drm_bridge *bridge,
+ struct drm_display_mode *mode,
+ struct drm_display_mode *adjusted_mode)
+{
+ struct dw_mipi_dsi *dsi = bridge->driver_private;
+ int ret;
+
+ dsi->mode = adjusted_mode;
+
+ ret = dw_mipi_dsi_get_lane_bps(dsi);
+ if (ret < 0)
+ return;
+
+ if (!IS_ERR(dsi->cfg_clk))
+ clk_prepare_enable(dsi->cfg_clk);
+
+ clk_prepare_enable(dsi->pclk);
+ dw_mipi_dsi_init(dsi);
+ dw_mipi_dsi_dpi_config(dsi, mode);
+ dw_mipi_dsi_packet_handler_config(dsi);
+ dw_mipi_dsi_video_mode_config(dsi);
+ dw_mipi_dsi_video_packet_config(dsi, mode);
+ dw_mipi_dsi_command_mode_config(dsi);
+ dw_mipi_dsi_line_timer_config(dsi);
+ dw_mipi_dsi_vertical_timing_config(dsi);
+ dw_mipi_dsi_dphy_timing_config(dsi);
+ dw_mipi_dsi_dphy_interface_config(dsi);
+ dw_mipi_dsi_clear_err(dsi);
+ dw_mipi_dsi_phy_init(dsi);
+ dw_mipi_dsi_wait_for_two_frames(dsi);
+ drm_panel_prepare(dsi->panel);
+ clk_disable_unprepare(dsi->pclk);
+
+ if (!IS_ERR(dsi->cfg_clk))
+ clk_disable_unprepare(dsi->cfg_clk);
+}
+
+static bool dw_mipi_dsi_bridge_mode_fixup(struct drm_bridge *bridge,
+ const struct drm_display_mode *mode,
+ struct drm_display_mode *adjusted_mode)
+{
+ return true;
+}
+
+static struct drm_bridge_funcs dw_mipi_dsi_bridge_funcs = {
+ .enable = dw_mipi_dsi_bridge_enable,
+ .disable = dw_mipi_dsi_bridge_disable,
+ .pre_enable = dw_mipi_dsi_bridge_nope,
+ .post_disable = dw_mipi_dsi_bridge_nope,
+ .mode_set = dw_mipi_dsi_bridge_mode_set,
+ .mode_fixup = dw_mipi_dsi_bridge_mode_fixup,
+};
+
+static int dw_mipi_dsi_register(struct drm_device *drm, struct dw_mipi_dsi *dsi)
+{
+ struct drm_encoder *encoder = dsi->encoder;
+ struct drm_bridge *bridge;
+ int ret;
+
+ bridge = devm_kzalloc(drm->dev, sizeof(*bridge), GFP_KERNEL);
+ if (!bridge)
+ return -ENOMEM;
+
+ dsi->bridge = bridge;
+ bridge->driver_private = dsi;
+
+ bridge->funcs = &dw_mipi_dsi_bridge_funcs;
+ ret = drm_bridge_attach(drm, bridge);
+ if (ret) {
+ DRM_ERROR("failed to initialize bridge with drm\n");
+ return ret;
+ }
+
+ encoder->bridge = bridge;
+
+ drm_connector_helper_add(&dsi->connector,
+ &dw_mipi_dsi_connector_helper_funcs);
+ drm_connector_init(drm, &dsi->connector, &dw_mipi_dsi_connector_funcs,
+ DRM_MODE_CONNECTOR_DSI);
+
+ drm_mode_connector_attach_encoder(&dsi->connector, dsi->encoder);
+
+ return 0;
+}
+
+int dw_mipi_dsi_bind(struct device *dev, struct device *master, void *data,
+ struct drm_encoder *encoder,
+ const struct dw_mipi_dsi_plat_data *pdata)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct resource *res;
+ struct drm_device *drm = data;
+ struct dw_mipi_dsi *dsi;
+ u32 val;
+ int ret;
+
+ dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
+ if (!dsi)
+ return -ENOMEM;
+
+ dsi->pdata = pdata;
+ dsi->dev = dev;
+ dsi->dsi_host.ops = &dw_mipi_dsi_host_ops;
+ dsi->dsi_host.dev = dev;
+ dsi->encoder = encoder;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ dsi->base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(dsi->base))
+ return PTR_ERR(dsi->base);
+
+ dsi->pllref_clk = devm_clk_get(dev, "ref");
+ if (IS_ERR(dsi->pllref_clk)) {
+ ret = PTR_ERR(dsi->pllref_clk);
+ dev_err(dev, "Unable to get pll reference clock: %d\n", ret);
+ return ret;
+ }
+ clk_prepare_enable(dsi->pllref_clk);
+
+ dsi->cfg_clk = devm_clk_get(dev, "cfg");
+ if (IS_ERR(dsi->cfg_clk))
+ dev_warn(dev, "Have no configuration clock\n");
+
+ dsi->pclk = devm_clk_get(dev, "pclk");
+ if (IS_ERR(dsi->pclk)) {
+ ret = PTR_ERR(dsi->pclk);
+ dev_err(dev, "Unable to get configuration clock: %d\n", ret);
+ goto err_pllref;
+ }
+
+ if (!IS_ERR(dsi->cfg_clk))
+ clk_prepare_enable(dsi->cfg_clk);
+
+ clk_prepare_enable(dsi->pclk);
+ val = dsi_read(dsi, DSI_VERSION);
+ clk_disable_unprepare(dsi->pclk);
+
+ if (!IS_ERR(dsi->cfg_clk))
+ clk_disable_unprepare(dsi->cfg_clk);
+
+ dev_info(dev, "version number is 0x%08x\n", val);
+
+ ret = dw_mipi_dsi_register(drm, dsi);
+ if (ret) {
+ dev_err(dev, "Unable to register dsi: %d\n", ret);
+ goto err_pllref;
+ }
+ dev_set_drvdata(dev, dsi);
+
+ return mipi_dsi_host_register(&dsi->dsi_host);
+
+err_pllref:
+ clk_disable_unprepare(dsi->pllref_clk);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dw_mipi_dsi_bind);
+
+void dw_mipi_dsi_unbind(struct device *dev, struct device *master, void *data)
+{
+ struct dw_mipi_dsi *dsi = dev_get_drvdata(dev);
+
+ mipi_dsi_host_unregister(&dsi->dsi_host);
+ clk_disable_unprepare(dsi->pllref_clk);
+}
+EXPORT_SYMBOL_GPL(dw_mipi_dsi_unbind);
+
+MODULE_DESCRIPTION("Synopsys DesignWare MIPI DSI host controller driver");
+MODULE_AUTHOR("Chris Zhong <zyw@xxxxxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
diff --git a/include/drm/bridge/dw_mipi_dsi.h b/include/drm/bridge/dw_mipi_dsi.h
new file mode 100644
index 0000000..2e351e4
--- /dev/null
+++ b/include/drm/bridge/dw_mipi_dsi.h
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2014-2015 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ */
+
+#ifndef __DW_MIPI_DSI__
+#define __DW_MIPI_DSI__
+
+#include <drm/drmP.h>
+
+struct dw_mipi_dsi_plat_data {
+ unsigned int max_data_lanes;
+ enum drm_mode_status (*mode_valid)(struct drm_connector *connector,
+ struct drm_display_mode *mode);
+};
+
+int dw_mipi_dsi_get_encoder_pixel_format(struct drm_encoder *encoder);
+
+int dw_mipi_dsi_bind(struct device *dev, struct device *master,
+ void *data, struct drm_encoder *encoder,
+ const struct dw_mipi_dsi_plat_data *pdata);
+void dw_mipi_dsi_unbind(struct device *dev, struct device *master, void *data);
+#endif /* __DW_MIPI_DSI__ */
--
2.6.3
--
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