From ba6984786294ad4e849473584611d3406f89a1d3 Mon Sep 17 00:00:00 2001
From: Janne Grunau <j@jannau.net>
Date: Sat, 25 Nov 2023 12:07:29 +0100
Subject: [PATCH] display: Add NO_DISPLAY build config to skip display init

Required for stage 1 loader to allow chainloaded display/dcp experiments
to start with the state left by iboot.

Signed-off-by: Janne Grunau <j@jannau.net>
---
 config.h      |  2 ++
 src/display.c | 12 ++++++++++++
 2 files changed, 14 insertions(+)

diff --git a/config.h b/config.h
index 7ba01566..31c89387 100644
--- a/config.h
+++ b/config.h
@@ -12,6 +12,8 @@
 
 // Minimal build for bring-up
 //#define BRINGUP
+// Disable display configuration / bringup on desktop devices
+//#define NO_DISPLAY
 
 // Print RTKit logs to the console
 //#define RTKIT_SYSLOG
diff --git a/src/display.c b/src/display.c
index 7145030c..19c5b697 100644
--- a/src/display.c
+++ b/src/display.c
@@ -1,5 +1,7 @@
 /* SPDX-License-Identifier: MIT */
 
+#include "../build/build_cfg.h"
+
 #include "display.h"
 #include "adt.h"
 #include "assert.h"
@@ -225,6 +227,11 @@ int display_start_dcp(void)
     if (iboot)
         return 0;
 
+#ifdef NO_DISPLAY
+    printf("display: NO_DISPLAY!\n");
+    return 0;
+#endif
+
     const display_config_t *disp_cfg = &display_config_m1;
 
     if (adt_is_compatible(adt, 0, "J473AP"))
@@ -350,6 +357,11 @@ int display_configure(const char *config)
     dcp_timing_mode_t want;
     struct display_options opts = {0};
 
+#ifdef NO_DISPLAY
+    printf("display: skip configuration (NO_DISPLAY)\n");
+    return 0;
+#endif
+
     display_parse_mode(config, &want, &opts);
 
     u64 start_time = get_ticks();