sunxi: video: Add a hpd_delay parameter to configure hpd delay

In some extreme cases it may be necessary to wait 1.5 seconds or more for a hpd
signal to show up (and be able to read edid info), but we do not want to
penalize all headless boots with an extra second boot delay, so add a hpd_delay
parameter which can be set through the video-mode env. variable.

While at it raise the default from 300ms to 500ms as 300 may very well be too
low in many cases.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>

diff --git a/doc/README.video b/doc/README.video
index 2c55d6a47262abe7a9296d47081498bf40f8a43d..d0a3ad6e8d455f52843778a93aa7a760f66c1b65 100644 (file)
--- a/doc/README.video
+++ b/doc/README.video
@@ -53,6 +53,12 @@ The sunxi u-boot driver supports the following video-mode options:
  1: Enabled.  Fallback to the lcd / vga / none in that order (if available)
  Defaults to hpd=1.
 
+- hpd_delay=<int> - How long to wait for the hdmi HPD signal in milliseconds
+ When the monitor and the board power up at the same time, it may take some
+ time for the monitor to assert the HPD signal. This configures how long to
+ wait for the HPD signal before assuming no cable is connected.
+ Defaults to hpd_delay=500.
+
 - edid=[0|1] - Enable use of DDC + EDID to get monitor info
  0: Disabled.
  1: Enabled. If valid EDID info was read from the monitor the EDID info will
@@ -61,4 +67,4 @@ The sunxi u-boot driver supports the following video-mode options:
 
 For example to always use the hdmi connector, even if no cable is inserted,
 using edid info when available and otherwise initalizing it at 1024x768@60Hz,
-use: video-mode=sunxi:1024x768-24@60,monitor=dvi,hpd=0,edid=1 .
+use: "setenv video-mode sunxi:1024x768-24@60,monitor=dvi,hpd=0,edid=1".

diff --git a/drivers/video/sunxi_display.c b/drivers/video/sunxi_display.c
index 536e1cac4db0f3fd47972cb677283a515ed8dec3..82414925afd38876674f366a72c333f1e24fe488 100644 (file)
--- a/drivers/video/sunxi_display.c
+++ b/drivers/video/sunxi_display.c
@@ -56,13 +56,13 @@ static int await_completion(u32 *reg, u32 mask, u32 val)
        return 0;
 }
 
-static int sunxi_hdmi_hpd_detect(void)
+static int sunxi_hdmi_hpd_detect(int hpd_delay)
 {
        struct sunxi_ccm_reg * const ccm =
                (struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
        struct sunxi_hdmi_reg * const hdmi =
                (struct sunxi_hdmi_reg *)SUNXI_HDMI_BASE;
-       unsigned long tmo = timer_get_us() + 300000;
+       unsigned long tmo = timer_get_us() + hpd_delay * 1000;
 
        /* Set pll3 to 300MHz */
        clock_set_pll3(300000000);
@@ -851,7 +851,7 @@ void *video_hw_init(void)
        struct ctfb_res_modes custom;
        const char *options;
 #ifdef CONFIG_VIDEO_HDMI
-       int ret, hpd, edid;
+       int ret, hpd, hpd_delay, edid;
 #endif
        char mon[16];
        char *lcd_mode = CONFIG_VIDEO_LCD_MODE;
@@ -867,6 +867,7 @@ void *video_hw_init(void)
                                 &sunxi_display.depth, &options);
 #ifdef CONFIG_VIDEO_HDMI
        hpd = video_get_option_int(options, "hpd", 1);
+       hpd_delay = video_get_option_int(options, "hpd_delay", 500);
        edid = video_get_option_int(options, "edid", 1);
        sunxi_display.monitor = sunxi_monitor_dvi;
 #elif defined CONFIG_VIDEO_VGA_VIA_LCD
@@ -891,7 +892,7 @@ void *video_hw_init(void)
        if (sunxi_display.monitor == sunxi_monitor_dvi ||
            sunxi_display.monitor == sunxi_monitor_hdmi) {
                /* Always call hdp_detect, as it also enables clocks, etc. */
-               ret = sunxi_hdmi_hpd_detect();
+               ret = sunxi_hdmi_hpd_detect(hpd_delay);
                if (ret) {
                        printf("HDMI connected: ");
                        if (edid && sunxi_hdmi_edid_get_mode(&custom) == 0)