x86: Initialize i8254 timer counter 1
authorBin Meng <bmeng.cn@gmail.com>
Fri, 23 Oct 2015 02:13:29 +0000 (19:13 -0700)
committerBin Meng <bmeng.cn@gmail.com>
Fri, 13 Nov 2015 14:46:18 +0000 (06:46 -0800)
Initialize counter 1, used to refresh request signal. This is
required for legacy purpose as some codes like vgabios utilizes
counter 1 to provide delay functionality.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
arch/x86/lib/pcat_timer.c

index ce15818ec276bae0cea667fa0a4f4ea36902aac6..347cdda9f6b264210c1a025fc4626c2839ecaeb3 100644 (file)
@@ -9,10 +9,20 @@
 #include <asm/io.h>
 #include <asm/i8254.h>
 
+#define TIMER1_VALUE   18      /* 15.6us */
 #define TIMER2_VALUE   0x0a8e  /* 440Hz */
 
 int pcat_timer_init(void)
 {
+       /*
+        * Initialize counter 1, used to refresh request signal.
+        * This is required for legacy purpose as some codes like
+        * vgabios utilizes counter 1 to provide delay functionality.
+        */
+       outb(PIT_CMD_CTR1 | PIT_CMD_LOW | PIT_CMD_MODE2,
+            PIT_BASE + PIT_COMMAND);
+       outb(TIMER1_VALUE, PIT_BASE + PIT_T1);
+
        /*
         * Initialize counter 2, used to drive the speaker.
         * To start a beep, set both bit0 and bit1 of port 0x61.