BUTTERFLY-FIRMWARE: Check keyboard more often in recovery mode

Currently we check the keyboard each 250ms. This makes for a pretty choppy
experience when changing languages. Change to check every 20ms, without
changing the disk check interval (which remains 1s).

BUG=chrome-os-partner:15396
BRANCH=butterfly
TEST=manual, verify basic firmware functions.

Change-Id: I2c7a810ec1358aa3ae7876c74ed7f857b9e14bde
Original-Change-Id: I2ae411bc36fdb2badac11595b099bca43f116669
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/35784
Reviewed-by: Shawn Nematbakhsh <shawnn@google.com>
Tested-by: Shawn Nematbakhsh <shawnn@google.com>

1 files changed, 8 insertions, 7 deletions

diff --git a/firmware/lib/vboot_api_kernel.c b/firmware/lib/vboot_api_kernel.c
index c0261e89..378400f0 100644
--- a/firmware/lib/vboot_api_kernel.c
+++ b/firmware/lib/vboot_api_kernel.c
@@ -285,8 +285,9 @@ fallout:
   return VbTryLoadKernel(cparams, p, VB_DISK_FLAG_FIXED);
 }
 
-/* Delay between disk checks in recovery mode */
-#define REC_DELAY_INCREMENT 250
+/* Delay in recovery mode */
+#define REC_DISK_DELAY 1000     /* Check disks every 1s */
+#define REC_KEY_DELAY  20       /* Check keys every 20ms */
 
 /* Handle a recovery-mode boot */
 VbError_t VbBootRecovery(VbCommonParams* cparams, LoadKernelParams* p) {
@@ -324,18 +325,18 @@ VbError_t VbBootRecovery(VbCommonParams* cparams, LoadKernelParams* p) {
 
       /* Scan keyboard more frequently than media, since x86 platforms
        * don't like to scan USB too rapidly. */
-      for (i = 0; i < 4; i++) {
+      for (i = 0; i < REC_DISK_DELAY; i += REC_KEY_DELAY) {
         VbCheckDisplayKey(cparams, VbExKeyboardRead(), &vnc);
         if (VbExIsShutdownRequested())
           return VBERROR_SHUTDOWN_REQUESTED;
-        VbExSleepMs(REC_DELAY_INCREMENT);
+        VbExSleepMs(REC_KEY_DELAY);
       }
     }
   }
 
   /* Loop and wait for a recovery image */
   while (1) {
-    VBDEBUG(("VbBootRecovery() attempting to load kernel\n"));
+    VBDEBUG(("VbBootRecovery() attempting to load kernel2\n"));
     retval = VbTryLoadKernel(cparams, p, VB_DISK_FLAG_REMOVABLE);
 
     /* Clear recovery requests from failed kernel loading, since we're
@@ -352,7 +353,7 @@ VbError_t VbBootRecovery(VbCommonParams* cparams, LoadKernelParams* p) {
 
     /* Scan keyboard more frequently than media, since x86 platforms don't like
      * to scan USB too rapidly. */
-    for (i = 0; i < 4; i++) {
+    for (i = 0; i < REC_DISK_DELAY; i += REC_KEY_DELAY) {
       key = VbExKeyboardRead();
       /* We might want to enter dev-mode from the Insert screen if... */
       if (key == 0x04 &&                /* user pressed Ctrl-D */
@@ -382,7 +383,7 @@ VbError_t VbBootRecovery(VbCommonParams* cparams, LoadKernelParams* p) {
         VbCheckDisplayKey(cparams, key, &vnc);
       if (VbExIsShutdownRequested())
         return VBERROR_SHUTDOWN_REQUESTED;
-      VbExSleepMs(REC_DELAY_INCREMENT);
+      VbExSleepMs(REC_KEY_DELAY);
     }
   }