These changes are the raw update to qemu-2.6.

[kvmfornfv.git] / qemu / roms / ipxe / src / arch / x86 / core / pit8254.c

diff --git a/qemu/roms/ipxe/src/arch/x86/core/pit8254.c b/qemu/roms/ipxe/src/arch/x86/core/pit8254.c
new file mode 100644 (file)
index 0000000..da20992
--- /dev/null
+++ b/qemu/roms/ipxe/src/arch/x86/core/pit8254.c
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+#include <assert.h>
+#include <ipxe/io.h>
+#include <ipxe/pit8254.h>
+
+/** @file
+ *
+ * 8254 Programmable Interval Timer
+ *
+ */
+
+/**
+ * Delay for a fixed number of timer ticks using the speaker channel
+ *
+ * @v ticks            Number of timer ticks for which to delay
+ */
+void pit8254_speaker_delay ( unsigned int ticks ) {
+       uint8_t spkr;
+       uint8_t cmd;
+       uint8_t low;
+       uint8_t high;
+
+       /* Sanity check */
+       assert ( ticks <= 0xffff );
+
+       /* Disable speaker, set speaker channel gate input high */
+       spkr = inb ( PIT8254_SPKR );
+       spkr &= ~PIT8254_SPKR_ENABLE;
+       spkr |= PIT8254_SPKR_GATE;
+       outb ( spkr, PIT8254_SPKR );
+
+       /* Program speaker channel to "interrupt" on terminal count */
+       cmd = ( PIT8254_CMD_CHANNEL ( PIT8254_CH_SPKR ) |
+               PIT8254_CMD_ACCESS_LOHI | PIT8254_CMD_OP_TERMINAL |
+               PIT8254_CMD_BINARY );
+       low = ( ( ticks >> 0 ) & 0xff );
+       high = ( ( ticks >> 8 ) & 0xff );
+       outb ( cmd, PIT8254_CMD );
+       outb ( low, PIT8254_DATA ( PIT8254_CH_SPKR ) );
+       outb ( high, PIT8254_DATA ( PIT8254_CH_SPKR ) );
+
+       /* Wait for channel to "interrupt" */
+       do {
+               spkr = inb ( PIT8254_SPKR );
+       } while ( ! ( spkr & PIT8254_SPKR_OUT ) );
+}