Stub out easter egg, in case BIOS wants to implement one.

BUG=none
TEST=manual

Type 'xyzzy' at dev-mode BIOS screen. What happens next depends on the BIOS.

Change-Id: Ifdb49eb6cb53ecee91f576be91679bd5a232f008
Reviewed-on: http://gerrit.chromium.org/gerrit/7656
Tested-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>

4 files changed, 26 insertions, 3 deletions

diff --git a/firmware/include/utility.h b/firmware/include/utility.h
index ddfd3d18..931789cb 100644
--- a/firmware/include/utility.h
+++ b/firmware/include/utility.h
@@ -43,6 +43,13 @@
 #define VbAssert(expr)
 #endif
 
+/* Optional, up to the BIOS */
+#ifdef VBOOT_EASTER_EGG
+#define VBEASTEREGG(A,B) VbExEasterEgg(A,B)
+#else
+#define VBEASTEREGG(A,B)
+#endif
+
 /* Combine [msw] and [lsw] uint16s to a uint32_t with its [msw] and
  * [lsw] forming the most and least signficant 16-bit words.
  */
diff --git a/firmware/lib/include/vboot_display.h b/firmware/lib/include/vboot_display.h
index 57688aed..8dc22606 100644
--- a/firmware/lib/include/vboot_display.h
+++ b/firmware/lib/include/vboot_display.h
@@ -19,5 +19,7 @@ VbError_t VbDisplayDebugInfo(VbCommonParams* cparams, VbNvContext *vncptr);
 VbError_t VbCheckDisplayKey(VbCommonParams* cparams, uint32_t key,
                             VbNvContext *vncptr);
 
+void VbExEasterEgg(VbCommonParams* cparams, VbNvContext *vncptr);
+
 #endif /* VBOOT_REFERENCE_VBOOT_DISPLAY_H_ */
 
diff --git a/firmware/lib/vboot_api_kernel.c b/firmware/lib/vboot_api_kernel.c
index 99ad7999..ed288103 100644
--- a/firmware/lib/vboot_api_kernel.c
+++ b/firmware/lib/vboot_api_kernel.c
@@ -109,7 +109,7 @@ VbError_t VbBootNormal(VbCommonParams* cparams, LoadKernelParams* p) {
 /* Developer mode delays.  All must be multiples of DEV_DELAY_INCREMENT */
 #define DEV_DELAY_INCREMENT 250  /* Delay each loop, in msec */
 #define DEV_DELAY_BEEP1 20000    /* Beep for first time at this time */
-#define DEV_DELAY_BEEP2 21000    /* Beep for second time at this time */
+#define DEV_DELAY_BEEP2 20500    /* Beep for second time at this time */
 #define DEV_DELAY_TIMEOUT 30000  /* Give up at this time */
 #define DEV_DELAY_TIMEOUT_SHORT 2000  /* Give up at this time (short delay) */
 
@@ -153,7 +153,7 @@ VbError_t VbBootDeveloper(VbCommonParams* cparams, LoadKernelParams* p) {
       case ' ':
       case 0x1B:
         /* Enter, space, or ESC = reboot to recovery */
-        VBDEBUG(("VbBootDeveloper() - user pressed ENTER/SPACE/ESC"));
+        VBDEBUG(("VbBootDeveloper() - user pressed ENTER/SPACE/ESC\n"));
         VbSetRecoveryRequest(VBNV_RECOVERY_RW_DEV_SCREEN);
         return 1;
       case 0x04:
@@ -185,7 +185,6 @@ VbError_t VbBootDeveloper(VbCommonParams* cparams, LoadKernelParams* p) {
       default:
         VbCheckDisplayKey(cparams, key, &vnc);
         break;
-        /* TODO: xyzzy easter egg check */
     }
   }
 
diff --git a/firmware/lib/vboot_display.c b/firmware/lib/vboot_display.c
index 9d759a86..b09c7748 100644
--- a/firmware/lib/vboot_display.c
+++ b/firmware/lib/vboot_display.c
@@ -461,8 +461,19 @@ VbError_t VbDisplayDebugInfo(VbCommonParams* cparams, VbNvContext *vncptr) {
 }
 
 
+#define MAGIC_WORD_LEN 5
+#define MAGIC_WORD     "xyzzy"
+static uint8_t MagicBuffer[MAGIC_WORD_LEN];
+
 VbError_t VbCheckDisplayKey(VbCommonParams* cparams, uint32_t key,
                             VbNvContext *vncptr) {
+  int i;
+
+  /* Update key buffer */
+  for(i=1; i<MAGIC_WORD_LEN; i++)
+    MagicBuffer[i-1] = MagicBuffer[i];
+  /* Save as lower-case ASCII */
+  MagicBuffer[MAGIC_WORD_LEN-1] = (key | 0x20) & 0xFF;
 
   if ('\t' == key) {
     /* Tab = display debug info */
@@ -488,5 +499,9 @@ VbError_t VbCheckDisplayKey(VbCommonParams* cparams, uint32_t key,
     return VbDisplayScreen(cparams, disp_current_screen, 1, vncptr);
   }
 
+  if (0 == Memcmp(MagicBuffer, MAGIC_WORD, MAGIC_WORD_LEN)) {
+    VBEASTEREGG(cparams, vncptr);
+  }
+
   return VBERROR_SUCCESS;
 }