On 07/01/2016 08:20 PM, Philipp Zabel wrote:
From: Andrey Gusakov <andrey.gusakov@xxxxxxxxxxxxxxxxxx>
Add a drm_bridge driver for the Toshiba TC358767 DPI/DSI to
eDP/DP bridge. Currently only DPI input with 24-bit RGB is
supported.
Signed-off-by: Andrey Gusakov <andrey.gusakov@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
---
drivers/gpu/drm/bridge/Kconfig | 8 +
drivers/gpu/drm/bridge/Makefile | 1 +
drivers/gpu/drm/bridge/tc358767.c | 1419 +++++++++++++++++++++++++++++++++++++
3 files changed, 1428 insertions(+)
create mode 100644 drivers/gpu/drm/bridge/tc358767.c
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index 8f7423f..04c2b6d 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -50,6 +50,14 @@ config DRM_PARADE_PS8622
---help---
Parade eDP-LVDS bridge chip driver.
+config DRM_TOSHIBA_TC358767
+ tristate "Toshiba TC358767 eDP bridge"
+ select DRM_KMS_HELPER
+ select REGMAP_I2C
+ select DRM_PANEL
+ ---help---
+ Toshiba TC358767 eDP bridge chip driver.
+
source "drivers/gpu/drm/bridge/analogix/Kconfig"
endmenu
diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
index 96b13b3..7c21a3c 100644
--- a/drivers/gpu/drm/bridge/Makefile
+++ b/drivers/gpu/drm/bridge/Makefile
@@ -5,4 +5,5 @@ obj-$(CONFIG_DRM_DW_HDMI) += dw-hdmi.o
obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw-hdmi-ahb-audio.o
obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
+obj-$(CONFIG_DRM_TOSHIBA_TC358767) += tc358767.o
obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix/
diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
new file mode 100644
index 0000000..515f123
--- /dev/null
+++ b/drivers/gpu/drm/bridge/tc358767.c
@@ -0,0 +1,1419 @@
+/*
+ * tc358767 eDP bridge driver
+ *
+ * Copyright (C) 2016 CogentEmbedded Inc
+ * Author: Andrey Gusakov <andrey.gusakov@xxxxxxxxxxxxxxxxxx>
+ *
+ * Copyright (C) 2016 Pengutronix, Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
+ *
+ * Initially based on: drivers/gpu/drm/i2c/tda998x_drv.c
+ *
+ * Copyright (C) 2012 Texas Instruments
+ * Author: Rob Clark <robdclark@xxxxxxxxx>
+ *
+ * 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.
+ *
+ * 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.
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include <drm/drmP.h>
This may not be needed.
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_dp_helper.h>
+#include <drm/drm_edid.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+
+/* Registers */
+
+/* Display Parallel Interface */
+#define DPIPXLFMT 0x0440
+#define VS_POL_ACTIVE_LOW (1 << 10)
+#define HS_POL_ACTIVE_LOW (1 << 9)
+#define DE_POL_ACTIVE_HIGH (0 << 8)
+#define SUB_CFG_TYPE_CONFIG1 (0 << 2) /* LSB aligned */
+#define SUB_CFG_TYPE_CONFIG2 (1 << 2) /* Loosely Packed */
+#define SUB_CFG_TYPE_CONFIG3 (2 << 2) /* LSB aligned 8-bit */
+#define DPI_BPP_RGB888 (0 << 0)
+#define DPI_BPP_RGB666 (1 << 0)
+#define DPI_BPP_RGB565 (2 << 0)
+
+/* Video Path */
+#define VPCTRL0 0x0450
+#define OPXLFMT_RGB666 (0 << 8)
+#define OPXLFMT_RGB888 (1 << 8)
+#define FRMSYNC_DISABLED (0 << 4) /* Video Timing Gen Disabled */
+#define FRMSYNC_ENABLED (1 << 4) /* Video Timing Gen Enabled */
+#define MSF_DISABLED (0 << 0) /* Magic Square FRC disabled */
+#define MSF_ENABLED (1 << 0) /* Magic Square FRC enabled */
+#define HTIM01 0x0454
+#define HTIM02 0x0458
+#define VTIM01 0x045c
+#define VTIM02 0x0460
+#define VFUEN0 0x0464
+#define VFUEN BIT(0) /* Video Frame Timing Upload */
+
+/* System */
+#define TC_IDREG 0x0500
+#define SYSCTRL 0x0510
+#define DP0_AUDSRC_NO_INPUT (0 << 3)
+#define DP0_AUDSRC_I2S_RX (1 << 3)
+#define DP0_VIDSRC_NO_INPUT (0 << 0)
+#define DP0_VIDSRC_DSI_RX (1 << 0)
+#define DP0_VIDSRC_DPI_RX (2 << 0)
+#define DP0_VIDSRC_COLOR_BAR (3 << 0)
+
+/* Control */
+#define DP0CTL 0x0600
+#define VID_MN_GEN BIT(6) /* Auto-generate M/N values */
+#define EF_EN BIT(5) /* Enable Enhanced Framing */
+#define VID_EN BIT(1) /* Video transmission enable */
+#define DP_EN BIT(0) /* Enable DPTX function */
+
+/* Clocks */
+#define DP0_VIDMNGEN0 0x0610
+#define DP0_VIDMNGEN1 0x0614
+#define DP0_VMNGENSTATUS 0x0618
+
+/* Main Channel */
+#define DP0_SECSAMPLE 0x0640
+#define DP0_VIDSYNCDELAY 0x0644
+#define DP0_TOTALVAL 0x0648
+#define DP0_STARTVAL 0x064c
+#define DP0_ACTIVEVAL 0x0650
+#define DP0_SYNCVAL 0x0654
+#define DP0_MISC 0x0658
+#define TU_SIZE_RECOMMENDED (0x3f << 16) /* LSCLK cycles per TU */
+#define BPC_6 (0 << 5)
+#define BPC_8 (1 << 5)
+
+/* AUX channel */
+#define DP0_AUXCFG0 0x0660
+#define DP0_AUXCFG1 0x0664
+#define AUX_RX_FILTER_EN BIT(16)
+
+#define DP0_AUXADDR 0x0668
+#define DP0_AUXWDATA(i) (0x066c + (i) * 4)
+#define DP0_AUXRDATA(i) (0x067c + (i) * 4)
+#define DP0_AUXSTATUS 0x068c
+#define AUX_STATUS_MASK 0xf0
+#define AUX_STATUS_SHIFT 4
+#define AUX_TIMEOUT BIT(1)
+#define AUX_BUSY BIT(0)
+#define DP0_AUXI2CADR 0x0698
+
+/* Link Training */
+#define DP0_SRCCTRL 0x06a0
+#define DP0_SRCCTRL_SCRMBLDIS BIT(13)
+#define DP0_SRCCTRL_EN810B BIT(12)
+#define DP0_SRCCTRL_NOTP (0 << 8)
+#define DP0_SRCCTRL_TP1 (1 << 8)
+#define DP0_SRCCTRL_TP2 (2 << 8)
+#define DP0_SRCCTRL_LANESKEW BIT(7)
+#define DP0_SRCCTRL_SSCG BIT(3)
+#define DP0_SRCCTRL_LANES_1 (0 << 2)
+#define DP0_SRCCTRL_LANES_2 (1 << 2)
+#define DP0_SRCCTRL_BW27 (1 << 1)
+#define DP0_SRCCTRL_BW162 (0 << 1)
+#define DP0_SRCCTRL_AUTOCORRECT BIT(0)
+#define DP0_LTSTAT 0x06d0
+#define LT_LOOPDONE BIT(13)
+#define LT_STATUS_MASK (0x1f << 8)
+#define LT_CHANNEL1_EQ_BITS (DP_CHANNEL_EQ_BITS << 4)
+#define LT_INTERLANE_ALIGN_DONE BIT(3)
+#define LT_CHANNEL0_EQ_BITS (DP_CHANNEL_EQ_BITS)
+#define DP0_SNKLTCHGREQ 0x06d4
+#define DP0_LTLOOPCTRL 0x06d8
+#define DP0_SNKLTCTRL 0x06e4
+
+/* PHY */
+#define DP_PHY_CTRL 0x0800
+#define DP_PHY_RST BIT(28) /* DP PHY Global Soft Reset */
+#define BGREN BIT(25) /* AUX PHY BGR Enable */
+#define PWR_SW_EN BIT(24) /* PHY Power Switch Enable */
+#define PHY_M1_RST BIT(12) /* Reset PHY1 Main Channel */
+#define PHY_RDY BIT(16) /* PHY Main Channels Ready */
+#define PHY_M0_RST BIT(8) /* Reset PHY0 Main Channel */
+#define PHY_A0_EN BIT(1) /* PHY Aux Channel0 Enable */
+#define PHY_M0_EN BIT(0) /* PHY Main Channel0 Enable */
+
+/* PLL */
+#define DP0_PLLCTRL 0x0900
+#define DP1_PLLCTRL 0x0904 /* not defined in DS */
+#define PXL_PLLCTRL 0x0908
+#define PLLUPDATE BIT(2)
+#define PLLBYP BIT(1)
+#define PLLEN BIT(0)
+#define PXL_PLLPARAM 0x0914
+#define IN_SEL_REFCLK (0 << 14)
+#define SYS_PLLPARAM 0x0918
+#define REF_FREQ_38M4 (0 << 8) /* 38.4 MHz */
+#define REF_FREQ_19M2 (1 << 8) /* 19.2 MHz */
+#define REF_FREQ_26M (2 << 8) /* 26 MHz */
+#define REF_FREQ_13M (3 << 8) /* 13 MHz */
+#define SYSCLK_SEL_LSCLK (0 << 4)
+#define LSCLK_DIV_1 (0 << 0)
+#define LSCLK_DIV_2 (1 << 0)
+
+/* Test & Debug */
+#define TSTCTL 0x0a00
+#define PLL_DBG 0x0a04
+
+struct tc_edp_link {
+ struct drm_dp_link base;
+ u8 assr;
+ int scrambler_dis;
+ int spread;
+ int coding8b10b;
+ u8 swing;
+ u8 preemp;
+};
+
+struct tc_data {
+ struct device *dev;
+ struct regmap *regmap;
+ struct drm_dp_aux aux;
+
+ struct drm_bridge bridge;
+ struct drm_connector connector;
+ struct drm_panel *panel;
+
+ /* link settings */
+ struct tc_edp_link link;
+
+ /* display edid */
+ struct edid *edid;
+ /* current mode */
+ struct drm_display_mode *mode;
+
+ /* PLL pixelclock */
+ u32 pll_clk;
+ u32 pll_clk_real;
+
+ int test_pattern;
+
+ u32 rev;
+ u8 assr;
+
+ struct gpio_desc *sd_gpio;
+ struct gpio_desc *reset_gpio;
+ struct clk *refclk;
+};
+
+static inline struct tc_data *aux_to_tc(struct drm_dp_aux *a)
+{
+ return container_of(a, struct tc_data, aux);
+}
+
+static inline struct tc_data *bridge_to_tc(struct drm_bridge *b)
+{
+ return container_of(b, struct tc_data, bridge);
+}
+
+static inline struct tc_data *connector_to_tc(struct drm_connector *c)
+{
+ return container_of(c, struct tc_data, connector);
+}
+
+/* Simple macros to avoid repeated error checks */
+#define tc_write(reg, var) \
+ do { \
+ ret = regmap_write(tc->regmap, reg, var); \
+ if (ret) \
+ goto err; \
+ } while (0)
+#define tc_read(reg, var) \
+ do { \
+ ret = regmap_read(tc->regmap, reg, var); \
+ if (ret) \
+ goto err; \
+ } while (0)
+
+#ifndef regmap_read_poll_timeout
+#define regmap_read_poll_timeout(map, addr, val, cond, sleep_us, timeout_us) \
+({ \
+ ktime_t timeout = ktime_add_us(ktime_get(), timeout_us); \
+ int ret; \
+ might_sleep_if(sleep_us); \
+ for (;;) { \
+ ret = regmap_read((map), (addr), &(val)); \
+ if (ret) \
+ break; \
+ if (cond) \
+ break; \
+ if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) { \
+ ret = regmap_read((map), (addr), &(val)); \
+ break; \
+ } \
+ if (sleep_us) \
+ usleep_range((sleep_us >> 2) + 1, sleep_us); \
+ } \
+ ret ?: ((cond) ? 0 : -ETIMEDOUT); \
+})
+#endif
Is there a reason why this is wrapped around a #ifndef? I don't see it
in the current regmap.h headers. It would also be nice if it were made
into a function.
+
+static int tc_aux_wait_busy(struct tc_data *tc, unsigned int timeout_ms)
+{
+ u32 value;
+
+ return regmap_read_poll_timeout(tc->regmap, DP0_AUXSTATUS, value,
+ !(value & AUX_BUSY),
+ 1000, 1000 * timeout_ms);
+}
+
+static int tc_aux_get_status(struct tc_data *tc, u8 *reply)
+{
+ int ret;
+ u32 value;
+
+ ret = regmap_read(tc->regmap, DP0_AUXSTATUS, &value);
+ if (ret < 0)
+ return ret;
+ if (value & AUX_BUSY) {
+ if (value & AUX_TIMEOUT) {
+ dev_err(tc->dev, "i2c access timeout!\n");
+ return -ETIMEDOUT;
+ }
+ return -EBUSY;
+ }
+
+ *reply = (value & AUX_STATUS_MASK) >> AUX_STATUS_SHIFT;
+ return 0;
+}
+
+static ssize_t tc_aux_transfer(struct drm_dp_aux *aux,
+ struct drm_dp_aux_msg *msg)
+{
+ struct tc_data *tc = aux_to_tc(aux);
+ size_t size = min_t(size_t, 8, msg->size);
+ u8 request = msg->request & ~DP_AUX_I2C_MOT;
+ u8 *buf = msg->buffer;
+ u32 tmp = 0;
+ int i = 0;
+ int ret;
+
+ if (size == 0)
+ return 0;
+
+ ret = tc_aux_wait_busy(tc, 100);
+ if (ret)
+ goto err;
+
+ if (request == DP_AUX_I2C_WRITE || request == DP_AUX_NATIVE_WRITE) {
+ /* Store data */
+ while (i < size) {
+ if (request == DP_AUX_NATIVE_WRITE)
+ tmp = tmp | (buf[i] << (8 * (i & 0x3)));
+ else
+ tmp = (tmp << 8) | buf[i];
+ i++;
+ if (((i % 4) == 0) || (i == size)) {
+ tc_write(DP0_AUXWDATA(i >> 2), tmp);
+ tmp = 0;
+ }
+ }
+ } else if (request != DP_AUX_I2C_READ &&
+ request != DP_AUX_NATIVE_READ) {
+ return -EINVAL;
+ }
+
+ /* Store address */
+ tc_write(DP0_AUXADDR, msg->address);
+ /* Start transfer */
+ tc_write(DP0_AUXCFG0, ((size - 1) << 8) | request);
+
+ ret = tc_aux_wait_busy(tc, 100);
+ if (ret)
+ goto err;
+
+ ret = tc_aux_get_status(tc, &msg->reply);
+ if (ret)
+ goto err;
+
+ if (request == DP_AUX_I2C_READ || request == DP_AUX_NATIVE_READ) {
+ /* Read data */
+ while (i < size) {
+ if ((i % 4) == 0)
+ tc_read(DP0_AUXRDATA(i >> 2), &tmp);
+ buf[i] = tmp & 0xff;
+ tmp = tmp >> 8;
+ i++;
+ }
+ }
+
+ return size;
+err:
+ return ret;
+}
+
+static const char * const training_pattern1_errors[] = {
+ "No errors",
+ "Aux write error",
+ "Aux read error",
+ "Max voltage reached error",
+ "Loop counter expired error",
+ "res", "res", "res"
+};
+
+static const char * const training_pattern2_errors[] = {
+ "No errors",
+ "Aux write error",
+ "Aux read error",
+ "Clock recovery failed error",
+ "Loop counter expired error",
+ "res", "res", "res"
+};
+
+static u32 tc_srcctrl(struct tc_data *tc)
+{
+ /*
+ * No training pattern, skew lane 1 data by two LSCLK cycles with
+ * respect to lane 0 data, AutoCorrect Mode = 0
+ */
+ u32 reg = DP0_SRCCTRL_NOTP | DP0_SRCCTRL_LANESKEW;
+
+ if (tc->link.scrambler_dis)
+ reg |= DP0_SRCCTRL_SCRMBLDIS; /* Scrambler Disabled */
+ if (tc->link.coding8b10b)
+ /* Enable 8/10B Encoder (TxData[19:16] not used) */
+ reg |= DP0_SRCCTRL_EN810B;
+ if (tc->link.spread)
+ reg |= DP0_SRCCTRL_SSCG; /* Spread Spectrum Enable */
+ if (tc->link.base.num_lanes == 2)
+ reg |= DP0_SRCCTRL_LANES_2; /* Two Main Channel Lanes */
+ if (tc->link.base.rate != 162000)
+ reg |= DP0_SRCCTRL_BW27; /* 2.7 Gbps link */
+ return reg;
+}
+
+static void tc_wait_pll_lock(struct tc_data *tc)
+{
+ /* Wait for PLL to lock: up to 2.09 ms, depending on refclk */
+ usleep_range(3000, 6000);
+}
+
+static int tc_pxl_pll_en(struct tc_data *tc, u32 refclk)
+{
+ int ret;
+ int i_pre, best_pre = 1;
+ int i_post, best_post = 1;
+ int div, best_div = 1;
+ int mul, best_mul = 1;
+ int delta, best_delta;
+ int ext_div[] = {1, 2, 3, 5, 7};
+ int best_pixelclock = 0;
+ int vco_hi = 0;
+ int pixelclock;
+
+ pixelclock = tc->pll_clk;
+
+ dev_dbg(tc->dev, "PLL: requested %d pixelclock, ref %d\n", pixelclock,
+ refclk);
+ best_delta = pixelclock;
+ /* big loops */
The above comment could be improved.
+ for (i_pre = 0; i_pre < ARRAY_SIZE(ext_div); i_pre++) {
+ /* refclk / ext_pre_div should be in the 1 to 200 MHz range */
+ if ((refclk / ext_div[i_pre] > 200000000) ||
The > 200 Mhz check seems redundant, since no refclk beyond 38.4 Mhz is
supported.
+ (refclk / ext_div[i_pre] < 1000000))
+ continue;
+ for (i_post = 0; i_post < ARRAY_SIZE(ext_div); i_post++) {
+ for (div = 1; div <= 16; div++) {
+ u32 clk;
+ u64 tmp;
+
+ tmp = pixelclock * ext_div[i_pre] *
+ ext_div[i_post] * div;
+ do_div(tmp, refclk);
+ mul = tmp;
+
+ clk = refclk / ext_div[i_pre] / div * mul /
+ ext_div[i_post];
Some braces for the above expression might help :)
+ delta = clk - pixelclock;
+
+ /* check limits */
+ if ((mul < 1) ||
+ (mul > 128))
minor comment: the above check could be in a single line.
+ continue;
+ /*
+ * refclk * mul / (ext_pre_div * pre_div)
+ * should be in the 150 to 650 MHz range
+ */
+ if ((refclk / ext_div[i_pre] / div * mul > 650000000) ||
+ (refclk / ext_div[i_pre] / div * mul < 150000000))
+ continue;
+
+ if (abs(delta) < abs(best_delta)) {
+ best_pre = i_pre;
+ best_post = i_post;
+ best_div = div;
+ best_mul = mul;
+ best_delta = delta;
+ best_pixelclock = clk;
+ }
+ }
+ }
+ }
+ if (best_pixelclock == 0) {
+ dev_err(tc->dev, "Failed to calc clock for %d pixelclock\n",
+ pixelclock);
+ return -EINVAL;
+ }
+
+ dev_dbg(tc->dev, "PLL: got %d, delta %d\n", best_pixelclock,
+ best_delta);
+ dev_dbg(tc->dev, "PLL: %d / %d / %d * %d / %d\n", refclk,
+ ext_div[best_pre], best_div, best_mul, ext_div[best_post]);
+
+ /* if VCO >= 300 MHz */
+ if (refclk / ext_div[best_pre] / best_div * best_mul >= 300000000)
+ vco_hi = 1;
+ /* see DS */
+ if (best_div == 16)
+ best_div = 0;
+ if (best_mul == 128)
+ best_mul = 0;
+
+ /* Power up PLL and switch to bypass */
+ tc_write(PXL_PLLCTRL, PLLBYP | PLLEN);
+
+ tc_write(PXL_PLLPARAM,
+ (vco_hi << 24) | /* For PLL VCO >= 300 MHz = 1 */
+ (ext_div[best_pre] << 20) | /* External Pre-divider */
+ (ext_div[best_post] << 16) | /* External Post-divider */
+ IN_SEL_REFCLK | /* Use RefClk as PLL input */
+ (best_div << 8) | /* Divider for PLL RefClk */
+ (best_mul << 0)); /* Multiplier for PLL */
+
+ /* Force PLL parameter update and disable bypass */
+ tc_write(PXL_PLLCTRL, PLLUPDATE | PLLEN);
+
+ tc_wait_pll_lock(tc);
+
+ /* save */
+ tc->pll_clk_real = best_pixelclock;
+
+ return 0;
+err:
+ return ret;
+}
+
+static int tc_pxl_pll_dis(struct tc_data *tc)
+{
+ /* Enable PLL bypass, power down PLL */
+ return regmap_write(tc->regmap, PXL_PLLCTRL, PLLBYP);
+}
+
+static int tc_stream_clock_calc(struct tc_data *tc)
+{
+ int ret;
+ /*
+ * If the Stream clock and Link Symbol clock are
+ * asynchronous with each other, the value of M changes over
+ * time. This way of generating link clock and stream
+ * clock is called Asynchronous Clock mode. The value M
+ * must change while the value N stays constant. The
+ * value of N in this Asynchronous Clock mode must be set
+ * to 2^15 or 32,768.
+ *
+ * LSCLK = 1/10 of high speed link clock
+ *
+ * f_STRMCLK = M/N * f_LSCLK
+ * M/N = f_STRMCLK / f_LSCLK
+ *
+ */
+ tc_write(DP0_VIDMNGEN1, 32768);
+
+ return 0;
+err:
+ return ret;
+}
+
+static int tc_aux_link_setup(struct tc_data *tc)
+{
+ unsigned long rate;
+ u32 value;
+ int ret;
+
+ rate = clk_get_rate(tc->refclk);
Ah, you can discard my comment on the clock binding in the DT patch.
I guess you needed it to figure out the rate.
+ switch (rate) {
+ case 38400000:
+ value = REF_FREQ_38M4;
+ break;
+ case 26000000:
+ value = REF_FREQ_26M;
+ break;
+ case 19200000:
+ value = REF_FREQ_19M2;
+ break;
+ case 13000000:
+ value = REF_FREQ_13M;
+ break;
+ default:
+ dev_err(tc->dev, "Invalid refclk rate: %lu Hz\n", rate);
+ return -EINVAL;
+ }
+
+ /* Setup DP-PHY / PLL */
+ value |= SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
+ tc_write(SYS_PLLPARAM, value);
+
+ tc_write(DP_PHY_CTRL, BGREN | PWR_SW_EN | BIT(2) | PHY_A0_EN);
It seems a bit strange to have BIT(2) besides the other predefined
macros.
+
+ /*
+ * Initially PLLs are in bypass. Force PLL parameter update,
+ * disable PLL bypass, enable PLL
+ */
+ tc_write(DP0_PLLCTRL, PLLUPDATE | PLLEN);
+ tc_wait_pll_lock(tc);
+
+ tc_write(DP1_PLLCTRL, PLLUPDATE | PLLEN);
+ tc_wait_pll_lock(tc);
+
+ ret = regmap_read_poll_timeout(tc->regmap, DP_PHY_CTRL, value,
+ value & PHY_RDY, 1, 1000);
+ if (ret == -ETIMEDOUT) {
+ dev_err(tc->dev, "Timeout waiting for PHY to become ready");
+ return ret;
+ } else if (ret)
+ goto err;
+
+ /* Setup AUX link */
+ tc_write(DP0_AUXCFG1, AUX_RX_FILTER_EN |
+ (0x06 << 8) | /* Aux Bit Period Calculator Threshold */
+ (0x3f << 0)); /* Aux Response Timeout Timer */
+
+ return 0;
+err:
+ dev_err(tc->dev, "tc_aux_link_setup failed: %d\n", ret);
+ return ret;
+}
+
+static int tc_get_display_props(struct tc_data *tc)
+{
+ int ret;
+ /* temp buffer */
+ u8 tmp[8];
+
+ /* Read DP Rx Link Capability */
+ ret = drm_dp_link_probe(&tc->aux, &tc->link.base);
+ if (ret < 0)
+ goto err_dpcd_read;
+ if ((tc->link.base.rate != 162000) && (tc->link.base.rate != 270000))
+ goto err_dpcd_inval;
+
+ ret = drm_dp_dpcd_readb(&tc->aux, DP_MAX_DOWNSPREAD, tmp);
+ if (ret < 0)
+ goto err_dpcd_read;
+ tc->link.spread = tmp[0] & BIT(0); /* 0.5% down spread */
+
+ ret = drm_dp_dpcd_readb(&tc->aux, DP_MAIN_LINK_CHANNEL_CODING, tmp);
+ if (ret < 0)
+ goto err_dpcd_read;
+ tc->link.coding8b10b = tmp[0] & BIT(0);
+ tc->link.scrambler_dis = 0;
+ /* read assr */
+ ret = drm_dp_dpcd_readb(&tc->aux, DP_EDP_CONFIGURATION_SET, tmp);
+ if (ret < 0)
+ goto err_dpcd_read;
+ tc->link.assr = tmp[0] & DP_ALTERNATE_SCRAMBLER_RESET_ENABLE;
+
+ dev_dbg(tc->dev, "DPCD rev: %d.%d, rate: %s, lanes: %d, framing: %s\n",
+ tc->link.base.revision >> 4, tc->link.base.revision & 0x0f,
+ (tc->link.base.rate == 162000) ? "1.62Gbps" : "2.7Gbps",
+ tc->link.base.num_lanes,
+ (tc->link.base.capabilities & DP_LINK_CAP_ENHANCED_FRAMING) ?
+ "enhanced" : "non-enhanced");
+ dev_dbg(tc->dev, "ANSI 8B/10B: %d\n", tc->link.coding8b10b);
+ dev_dbg(tc->dev, "Display ASSR: %d, TC358767 ASSR: %d\n",
+ tc->link.assr, tc->assr);
+
+ return 0;
+
+err_dpcd_read:
+ dev_err(tc->dev, "failed to read DPCD: %d\n", ret);
+ return ret;
+err_dpcd_inval:
+ dev_err(tc->dev, "invalid DPCD\n");
+ return -EINVAL;
+}
+
+static int tc_set_video_mode(struct tc_data *tc, struct drm_display_mode *mode)
+{
+ int ret;
+ int vid_sync_dly;
+ int max_tu_symbol;
+
+ int left_margin = mode->htotal - mode->hsync_end;
+ int right_margin = mode->hsync_start - mode->hdisplay;
+ int hsync_len = mode->hsync_end - mode->hsync_start;
+ int upper_margin = mode->vtotal - mode->vsync_end;
+ int lower_margin = mode->vsync_start - mode->vdisplay;
+ int vsync_len = mode->vsync_end - mode->vsync_start;
+
+ dev_dbg(tc->dev, "set mode %dx%d\n",
+ mode->hdisplay, mode->vdisplay);
+ dev_dbg(tc->dev, "H margin %d,%d sync %d\n",
+ left_margin, right_margin, hsync_len);
+ dev_dbg(tc->dev, "V margin %d,%d sync %d\n",
+ upper_margin, lower_margin, vsync_len);
+ dev_dbg(tc->dev, "total: %dx%d\n", mode->htotal, mode->vtotal);
+
+
+ /* LCD Ctl Frame Size */
+ tc_write(VPCTRL0, (0x40 << 20) /* VSDELAY */ |
+ OPXLFMT_RGB888 | FRMSYNC_DISABLED | MSF_DISABLED);
+ tc_write(HTIM01, (left_margin << 16) | /* H back porch */
+ (hsync_len << 0)); /* Hsync */
+ tc_write(HTIM02, (right_margin << 16) | /* H front porch */
+ (mode->hdisplay << 0)); /* width */
+ tc_write(VTIM01, (upper_margin << 16) | /* V back porch */
+ (vsync_len << 0)); /* Vsync */
+ tc_write(VTIM02, (lower_margin << 16) | /* V front porch */
+ (mode->vdisplay << 0)); /* height */
+ tc_write(VFUEN0, VFUEN); /* update settings */
+
+ /* Test pattern settings */
+ tc_write(TSTCTL,
+ (120 << 24) | /* Red Color component value */
+ (20 << 16) | /* Green Color component value */
+ (99 << 8) | /* Blue Color component value */
+ (1 << 4) | /* Enable I2C Filter */
+ (2 << 0) | /* Color bar Mode */
+ 0);
+
+ /* DP Main Stream Attributes */
+ vid_sync_dly = hsync_len + left_margin + mode->hdisplay;
+ tc_write(DP0_VIDSYNCDELAY,
+ (0x003e << 16) | /* thresh_dly */
+ (vid_sync_dly << 0));
+
+ tc_write(DP0_TOTALVAL, (mode->vtotal << 16) | (mode->htotal));
+
+ tc_write(DP0_STARTVAL,
+ ((upper_margin + vsync_len) << 16) |
+ ((left_margin + hsync_len) << 0));
+
+ tc_write(DP0_ACTIVEVAL, (mode->vdisplay << 16) | (mode->hdisplay));
+
+ tc_write(DP0_SYNCVAL, (vsync_len << 16) | (hsync_len << 0));
+
+ tc_write(DPIPXLFMT, VS_POL_ACTIVE_LOW | HS_POL_ACTIVE_LOW |
+ DE_POL_ACTIVE_HIGH | SUB_CFG_TYPE_CONFIG1 | DPI_BPP_RGB888);
+
+ /*
+ * Recommended maximum number of symbols transferred in a transfer unit:
+ * DIV_ROUND_UP((input active video bandwidth in bytes) * tu_size,
+ * (output active video bandwidth in bytes))
+ * Must be less than tu_size.
+ */
+ max_tu_symbol = TU_SIZE_RECOMMENDED - 1;
+ tc_write(DP0_MISC, (max_tu_symbol << 23) | TU_SIZE_RECOMMENDED | BPC_8);
+
+ return 0;
+err:
+ return ret;
+}
+
+static int tc_link_training(struct tc_data *tc, int pattern)
+{
+ const char * const *errors;
+ u32 srcctrl = tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS |
+ DP0_SRCCTRL_AUTOCORRECT;
+ int timeout;
+ int retry;
+ u32 value;
+ int ret;
+
+ if (pattern == DP_TRAINING_PATTERN_1) {
+ srcctrl |= DP0_SRCCTRL_TP1;
+ errors = training_pattern1_errors;
+ } else {
+ srcctrl |= DP0_SRCCTRL_TP2;
+ errors = training_pattern2_errors;
+ }
+
+ /* Set DPCD 0x102 for Training Part 1 or 2 */
+ tc_write(DP0_SNKLTCTRL, DP_LINK_SCRAMBLING_DISABLE | pattern);
+
+ tc_write(DP0_LTLOOPCTRL,
+ (0x0f << 28) | /* Defer Iteration Count */
+ (0x0f << 24) | /* Loop Iteration Count */
+ (0x0d << 0)); /* Loop Timer Delay */
+
+ retry = 5;
+ do {
+ /* Set DP0 Training Pattern */
+ tc_write(DP0_SRCCTRL, srcctrl);
+
+ /* Enable DP0 to start Link Training */
+ tc_write(DP0CTL, DP_EN);
+
+ /* wait */
+ timeout = 1000;
+ do {
+ tc_read(DP0_LTSTAT, &value);
+ udelay(1);
+ } while ((!(value & LT_LOOPDONE)) && (--timeout));
+ if (timeout == 0) {
+ dev_err(tc->dev, "Link training timeout!\n");
+ } else {
+ int pattern = (value >> 11) & 0x3;
+ int error = (value >> 8) & 0x7;
+
+ dev_dbg(tc->dev,
+ "Link training phase %d done after %d uS: %s\n",
+ pattern, 1000 - timeout, errors[error]);
+ if (pattern == DP_TRAINING_PATTERN_1 && error == 0)
+ break;
+ if (pattern == DP_TRAINING_PATTERN_2) {
+ value &= LT_CHANNEL1_EQ_BITS |
+ LT_INTERLANE_ALIGN_DONE |
+ LT_CHANNEL0_EQ_BITS;
+ /* in case of two lanes */
+ if ((tc->link.base.num_lanes == 2) &&
+ (value == (LT_CHANNEL1_EQ_BITS |
+ LT_INTERLANE_ALIGN_DONE |
+ LT_CHANNEL0_EQ_BITS)))
+ break;
+ /* in case of one line */
+ if ((tc->link.base.num_lanes == 1) &&
+ (value == (LT_INTERLANE_ALIGN_DONE |
+ LT_CHANNEL0_EQ_BITS)))
+ break;
+ }
+ }
+ /* restart */
+ tc_write(DP0CTL, 0);
+ usleep_range(10, 20);
+ } while (--retry);
+ if (retry == 0) {
+ dev_err(tc->dev, "Failed to finish training phase %d\n",
+ pattern);
+ }
+
+ return 0;
+err:
+ return ret;
+}
+
+static int tc_main_link_setup(struct tc_data *tc)
+{
+ struct drm_dp_aux *aux = &tc->aux;
+ struct device *dev = tc->dev;
+ unsigned int rate;
+ u32 dp_phy_ctrl;
+ int timeout;
+ bool aligned;
+ bool ready;
+ u32 value;
+ int ret;
+ u8 tmp[8];
+
+ /* display mode should be set at this point */
+ if (!tc->mode)
+ return -EINVAL;
+
+ /* from excel file - DP0_SrcCtrl */
+ tc_write(DP0_SRCCTRL, DP0_SRCCTRL_SCRMBLDIS | DP0_SRCCTRL_EN810B |
+ DP0_SRCCTRL_LANESKEW | DP0_SRCCTRL_LANES_2 |
+ DP0_SRCCTRL_BW27 | DP0_SRCCTRL_AUTOCORRECT);
+ /* from excel file - DP1_SrcCtrl */
+ tc_write(0x07a0, 0x00003083);
+
+ rate = clk_get_rate(tc->refclk);
+ switch (rate) {
+ case 38400000:
+ value = REF_FREQ_38M4;
+ break;
+ case 26000000:
+ value = REF_FREQ_26M;
+ break;
+ case 19200000:
+ value = REF_FREQ_19M2;
+ break;
+ case 13000000:
+ value = REF_FREQ_13M;
+ break;
+ default:
+ return -EINVAL;
+ }
+ value |= SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
+ tc_write(SYS_PLLPARAM, value);
+ /* Setup Main Link */
+ dp_phy_ctrl = BGREN | PWR_SW_EN | BIT(2) | PHY_A0_EN | PHY_M0_EN;
+ tc_write(DP_PHY_CTRL, dp_phy_ctrl);
+ msleep(100);
+
+ /* PLL setup */
+ tc_write(DP0_PLLCTRL, PLLUPDATE | PLLEN);
+ tc_wait_pll_lock(tc);
+
+ tc_write(DP1_PLLCTRL, PLLUPDATE | PLLEN);
+ tc_wait_pll_lock(tc);
+
+ /* PXL PLL setup */
+ if (tc->test_pattern) {
I couldn't find out who is setting tc->test_pattern. Is it always
0?
+ ret = tc_pxl_pll_en(tc, clk_get_rate(tc->refclk));
+ if (ret)
+ goto err;
+ }
+
+ /* Reset/Enable Main Links */
+ dp_phy_ctrl |= DP_PHY_RST | PHY_M1_RST | PHY_M0_RST;
+ tc_write(DP_PHY_CTRL, dp_phy_ctrl);
+ usleep_range(100, 200);
+ dp_phy_ctrl &= ~(DP_PHY_RST | PHY_M1_RST | PHY_M0_RST);
+ tc_write(DP_PHY_CTRL, dp_phy_ctrl);
+
+ timeout = 1000;
+ do {
+ tc_read(DP_PHY_CTRL, &value);
+ udelay(1);
+ } while ((!(value & PHY_RDY)) && (--timeout));
+
+ if (timeout == 0) {
+ dev_err(dev, "timeout waiting for phy become ready");
+ return -ETIMEDOUT;
+ }
+
+ /* Set misc: 8 bits per color */
+ ret = regmap_update_bits(tc->regmap, DP0_MISC, BPC_8, BPC_8);
+ if (ret)
+ goto err;
+
+ /*
+ * ASSR mode
+ * on TC358767 side ASSR configured through strap pin
+ * seems there is no way to change this setting from SW
+ *
+ * check is tc configured for same mode
+ */
+ if (tc->assr != tc->link.assr) {
+ dev_dbg(dev, "Trying to set display to ASSR: %d\n",
+ tc->assr);
+ /* try to set ASSR on display side */
+ tmp[0] = tc->assr;
+ ret = drm_dp_dpcd_writeb(aux, DP_EDP_CONFIGURATION_SET, tmp[0]);
+ if (ret < 0)
+ goto err_dpcd_read;
+ /* read back */
+ ret = drm_dp_dpcd_readb(aux, DP_EDP_CONFIGURATION_SET, tmp);
+ if (ret < 0)
+ goto err_dpcd_read;
+
+ if (tmp[0] != tc->assr) {
+ dev_warn(dev, "Failed to switch display ASSR to %d, falling back to unscrambled mode\n",
+ tc->assr);
+ /* trying with disabled scrambler */
+ tc->link.scrambler_dis = 1;
+ }
+ }
+
+ /* Setup Link & DPRx Config for Training */
+ ret = drm_dp_link_configure(aux, &tc->link.base);
+ if (ret < 0)
+ goto err_dpcd_write;
+
+ /* DOWNSPREAD_CTRL */
+ tmp[0] = tc->link.spread ? DP_SPREAD_AMP_0_5 : 0x00;
+ /* MAIN_LINK_CHANNEL_CODING_SET */
+ tmp[1] = tc->link.coding8b10b ? DP_SET_ANSI_8B10B : 0x00;
+ ret = drm_dp_dpcd_write(aux, DP_DOWNSPREAD_CTRL, tmp, 2);
+ if (ret < 0)
+ goto err_dpcd_write;
+
+ ret = tc_link_training(tc, DP_TRAINING_PATTERN_1);
+ if (ret)
+ goto err;
+
+ ret = tc_link_training(tc, DP_TRAINING_PATTERN_2);
+ if (ret)
+ goto err;
+
+ /* Clear DPCD 0x102 */
+ /* Note: Can Not use DP0_SNKLTCTRL (0x06E4) short cut */
+ tmp[0] = tc->link.scrambler_dis ? DP_LINK_SCRAMBLING_DISABLE : 0x00;
+ ret = drm_dp_dpcd_writeb(aux, DP_TRAINING_PATTERN_SET, tmp[0]);
+ if (ret < 0)
+ goto err_dpcd_write;
+
+ /* Clear Training Pattern, set AutoCorrect Mode = 1 */
+ tc_write(DP0_SRCCTRL, tc_srcctrl(tc) | DP0_SRCCTRL_AUTOCORRECT);
+
+ /* Wait */
+ timeout = 100;
+ do {
+ udelay(1);
+ /* Read DPCD 0x202-0x207 */
+ ret = drm_dp_dpcd_read_link_status(aux, tmp + 2);
+ if (ret < 0)
+ goto err_dpcd_read;
+ ready = (tmp[2] == ((DP_CHANNEL_EQ_BITS << 4) | /* Lane1 */
+ DP_CHANNEL_EQ_BITS)); /* Lane0 */
+ aligned = tmp[4] & DP_INTERLANE_ALIGN_DONE;
+ } while ((--timeout) && !(ready && aligned));
+
+ if (timeout == 0) {
+ /* Read DPCD 0x200-0x201 */
+ ret = drm_dp_dpcd_read(aux, DP_SINK_COUNT, tmp, 2);
+ if (ret < 0)
+ goto err_dpcd_read;
+ dev_info(dev, "0x0200 SINK_COUNT: 0x%02x\n", tmp[0]);
+ dev_info(dev, "0x0201 DEVICE_SERVICE_IRQ_VECTOR: 0x%02x\n",
+ tmp[1]);
+ dev_info(dev, "0x0202 LANE0_1_STATUS: 0x%02x\n", tmp[2]);
+ dev_info(dev, "0x0204 LANE_ALIGN_STATUS_UPDATED: 0x%02x\n",
+ tmp[4]);
+ dev_info(dev, "0x0205 SINK_STATUS: 0x%02x\n", tmp[5]);
+ dev_info(dev, "0x0206 ADJUST_REQUEST_LANE0_1: 0x%02x\n",
+ tmp[6]);
+
+ if (!ready)
+ dev_err(dev, "Lane0/1 not ready\n");
+ if (!aligned)
+ dev_err(dev, "Lane0/1 not aligned\n");
+ return -EAGAIN;
+ }
+
+ ret = tc_set_video_mode(tc, tc->mode);
+ if (ret)
+ goto err;
+
+ /* Set M/N */
+ ret = tc_stream_clock_calc(tc);
+ if (ret)
+ goto err;
+
+ return 0;
+err_dpcd_read:
+ dev_err(tc->dev, "Failed to read DPCD: %d\n", ret);
+ return ret;
+err_dpcd_write:
+ dev_err(tc->dev, "Failed to write DPCD: %d\n", ret);
+err:
+ return ret;
+}
+
+static int tc_main_link_stream(struct tc_data *tc, int state)
+{
+ int ret;
+ u32 value;
+
+ dev_dbg(tc->dev, "stream: %d\n", state);
+
+ if (state) {
+ value = VID_MN_GEN | DP_EN;
+ if (tc->link.base.capabilities & DP_LINK_CAP_ENHANCED_FRAMING)
+ value |= EF_EN;
+ tc_write(DP0CTL, value);
+ /*
+ * VID_EN assertion should be delayed by at least N * LSCLK
+ * cycles from the time VID_MN_GEN is enabled in order to
+ * generate stable values for VID_M. LSCLK is 270 MHz or
+ * 162 MHz, VID_N is set to 32768 in tc_stream_clock_calc(),
+ * so a delay of at least 203 us should suffice.
+ */
+ usleep_range(500, 1000);
+ value |= VID_EN;
+ tc_write(DP0CTL, value);
+ /* Set input interface */
+ value = DP0_AUDSRC_NO_INPUT;
+ if (tc->test_pattern)
+ value |= DP0_VIDSRC_COLOR_BAR;
+ else
+ value |= DP0_VIDSRC_DPI_RX;
+ tc_write(SYSCTRL, value);
+ } else {
+ tc_write(DP0CTL, 0);
+ }
+
+ return 0;
+err:
+ return ret;
+}
+
+static enum drm_connector_status
+tc_connector_detect(struct drm_connector *connector, bool force)
+{
+ return connector_status_connected;
+}
+
+static void tc_bridge_pre_enable(struct drm_bridge *bridge)
+{
+ struct tc_data *tc = bridge_to_tc(bridge);
+
+ drm_panel_prepare(tc->panel);
+}
+
+static void tc_bridge_enable(struct drm_bridge *bridge)
+{
+ struct tc_data *tc = bridge_to_tc(bridge);
+ int ret;
+
+ ret = tc_main_link_setup(tc);
+ if (ret < 0) {
+ dev_err(tc->dev, "main link setup error: %d\n", ret);
+ return;
+ }
+
+ ret = tc_main_link_stream(tc, 1);
+ if (ret < 0) {
+ dev_err(tc->dev, "main link stream start error: %d\n", ret);
+ return;
+ }
+
+ drm_panel_enable(tc->panel);
+}
+
+static void tc_bridge_disable(struct drm_bridge *bridge)
+{
+ struct tc_data *tc = bridge_to_tc(bridge);
+ int ret;
+
+ drm_panel_disable(tc->panel);
+
+ ret = tc_main_link_stream(tc, 0);
+ if (ret < 0)
+ dev_err(tc->dev, "main link stream stop error: %d\n", ret);
+}
+
+static void tc_bridge_post_disable(struct drm_bridge *bridge)
+{
+ struct tc_data *tc = bridge_to_tc(bridge);
+
+ drm_panel_unprepare(tc->panel);
+}
+
+static bool tc_bridge_mode_fixup(struct drm_bridge *bridge,
+ const struct drm_display_mode *mode,
+ struct drm_display_mode *adj)
+{
+ /* Fixup sync polarities, both hsync and vsync are active low */
+ adj->flags = mode->flags;
+ adj->flags |= (DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
+ adj->flags &= ~(DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
+
+ return true;
+}
+
+static int tc_connector_mode_valid(struct drm_connector *connector,
+ struct drm_display_mode *mode)
+{
+ /* Accept any mode */
+ return MODE_OK;
+}
+
+static void tc_bridge_mode_set(struct drm_bridge *bridge,
+ struct drm_display_mode *mode,
+ struct drm_display_mode *adj)
+{
+ struct tc_data *tc = bridge_to_tc(bridge);
+
+ tc->mode = mode;
+}
+
+static int tc_connector_get_modes(struct drm_connector *connector)
+{
+ struct tc_data *tc = connector_to_tc(connector);
+ struct edid *edid;
+ unsigned int count;
+
+ if (tc->panel && tc->panel->funcs && tc->panel->funcs->get_modes) {
+ count = tc->panel->funcs->get_modes(tc->panel);
+ if (count > 0)
+ return count;
+ }
+
+ edid = drm_get_edid(connector, &tc->aux.ddc);
+
+ kfree(tc->edid);
+ tc->edid = edid;
+ if (!edid)
+ return 0;
+
+ drm_mode_connector_update_edid_property(connector, edid);
+ count = drm_add_edid_modes(connector, edid);
+
+ return count;
+}
+
+static void tc_connector_set_polling(struct tc_data *tc,
+ struct drm_connector *connector)
+{
+ /* TODO: add support for HPD */
+ connector->polled = DRM_CONNECTOR_POLL_CONNECT |
+ DRM_CONNECTOR_POLL_DISCONNECT;
+}
+
+static struct drm_encoder *
+tc_connector_best_encoder(struct drm_connector *connector)
+{
+ struct tc_data *tc = connector_to_tc(connector);
+
+ return tc->bridge.encoder;
+}
+
+static const struct drm_connector_helper_funcs tc_connector_helper_funcs = {
+ .get_modes = tc_connector_get_modes,
+ .mode_valid = tc_connector_mode_valid,
+ .best_encoder = tc_connector_best_encoder,
+};
+
+static void tc_connector_destroy(struct drm_connector *connector)
+{
+ drm_connector_unregister(connector);
+ drm_connector_cleanup(connector);
+}
+
+static const struct drm_connector_funcs tc_connector_funcs = {
+ .dpms = drm_helper_connector_dpms,
+ .fill_modes = drm_helper_probe_single_connector_modes,
+ .detect = tc_connector_detect,
+ .destroy = tc_connector_destroy,
Can we use atomic helpers where applicable?
Thanks,
Archit
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