New patch to review for coreboot: a3b8f6c pit: Redo the display port bridge initialization code.

[Gabe Black]

Gabe Black ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/3723

-gerrit

commit a3b8f6ca17345bca0411acc585894ab5c4129fc0
Author: Gabe Black 
Date:   Sun Jun 30 05:19:53 2013 -0700

pit: Redo the display port bridge initialization code.

The display port bridge on pit is different from the one on snow and needs to
    be initialized differently. Instead of waiting for the chip to come up on its
    own and assert the hotplug detect, we need to access it over i2c and get it up
    and running ourselves.

Change-Id: I4bc911cb8e4463edff7beabd2f356cb70ae9f507
    Signed-off-by: Gabe Black 
---
 src/mainboard/google/pit/mainboard.c | 71 +++++++++---------------------------
 1 file changed, 17 insertions(+), 54 deletions(-)

diff --git a/src/mainboard/google/pit/mainboard.c b/src/mainboard/google/pit/mainboard.c
index 67d3b5d..54ea042 100644
--- a/src/mainboard/google/pit/mainboard.c
+++ b/src/mainboard/google/pit/mainboard.c
@@ -34,7 +34,9 @@
 #include <cpu/samsung/exynos5420/power.h>
 #include <cpu/samsung/exynos5420/i2c.h>
 #include <cpu/samsung/exynos5420/dp-core.h>
+#include <drivers/parade/ps8625/ps8625.h>
 #include <ec/google/chromeec/ec.h>
+#include <stdlib.h>

#include "exynos5420.h"

@@ -56,7 +58,7 @@ static enum exynos5_gpio_pin dp_hpd = GPIO_X26;		/* active high */
 static enum exynos5_gpio_pin bl_pwm = GPIO_B20;		/* active high */
 static enum exynos5_gpio_pin bl_en = GPIO_X22;		/* active high */

-static void exynos_dp_bridge_setup(void)
+static void parade_dp_bridge_setup(void)
 {
    gpio_set_value(dp_pd_l, 1);
    gpio_cfg_pin(dp_pd_l, GPIO_OUTPUT);
@@ -69,37 +71,19 @@ static void exynos_dp_bridge_setup(void)
    gpio_set_value(dp_rst_l, 1);

gpio_cfg_pin(dp_hpd, GPIO_INPUT);
-}

-static void exynos_dp_bridge_init(void)
-{
-	/* De-assert PD (and possibly RST) to power up the bridge */
+	/* De-assert PD (and possibly RST) to power up the bridge. */
    gpio_set_value(dp_pd_l, 1);
    gpio_set_value(dp_rst_l, 1);

-	/*
-	 * We need to wait for 90ms after bringing up the bridge since
-	 * there is a phantom "high" on the HPD chip during its
-	 * bootup.  The phantom high comes within 7ms of de-asserting
-	 * PD and persists for at least 15ms.  The real high comes
-	 * roughly 50ms after PD is de-asserted. The phantom high
-	 * makes it hard for us to know when the NXP chip is up.
-	 */
-	udelay(90000);
-}
+	/* Hang around for the bridge to come up. */
+	mdelay(40);

-static int exynos_dp_hotplug(void)
-{
-	/* Check HPD.  If it's high, we're all good. */
-	return gpio_get_value(dp_hpd) ? 0 : 1;
-}
+	/* Configure the bridge chip. */
+	exynos_pinmux_i2c7();
+	i2c_init(7, 100000, 0x00);

-static void exynos_dp_reset(void)
-{
-	gpio_set_value(dp_pd_l, 0);
-	gpio_set_value(dp_rst_l, 0);
-	/* paranoid delay period (300ms) */
-	udelay(300 * 1000);
+	parade_ps8625_bridge_setup(7, 0x48);
 }

/*
@@ -203,7 +187,6 @@ static void backlight_vdd(void)
 /* this happens after cpu_init where exynos resources are set */
 static void mainboard_init(device_t dev)
 {
-	int dp_tries;
    struct s5p_dp_device dp_device = {
    	.base = (struct exynos5_dp *)EXYNOS5420_DP1_BASE,
    	.video_info = &dp_video_info,
@@ -225,34 +208,14 @@ static void mainboard_init(device_t dev)

lcd_vdd();

-	// FIXME: should timeout
-	do {
-		udelay(50);
-	} while (!exynos_dp_hotplug());
-
-	exynos_dp_bridge_setup();
-	for (dp_tries = 1; dp_tries <= MAX_DP_TRIES; dp_tries++) {
-		exynos_dp_bridge_init();
-		if (exynos_dp_hotplug()) {
-			printk(BIOS_ERR, "Hotplug detect failed.\n");
-			exynos_dp_reset();
-			continue;
-		}
-
-		if (dp_controller_init(&dp_device))
-			continue;
-
-		udelay(LCD_T3_DELAY_MS * 1000);
-
-		backlight_vdd();
-		backlight_pwm();
-		backlight_en();
-		/* if we're here, we're successful */
-		break;
-	}
+	parade_dp_bridge_setup();
+	dp_controller_init(&dp_device);
+
+	udelay(LCD_T3_DELAY_MS * 1000);

-	if (dp_tries > MAX_DP_TRIES)
-		printk(BIOS_ERR, "%s: Failed to set up displayport\n", __func__);
+	backlight_vdd();
+	backlight_pwm();
+	backlight_en();

// Uncomment to get excessive GPIO output:
    // gpio_info();