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