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-rw-r--r--arch/x86/cpu/sc520/sc520_timer.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/arch/x86/cpu/sc520/sc520_timer.c b/arch/x86/cpu/sc520/sc520_timer.c
new file mode 100644
index 0000000000..1bcfe67c94
--- /dev/null
+++ b/arch/x86/cpu/sc520/sc520_timer.c
@@ -0,0 +1,90 @@
+/*
+ * (C) Copyright 2008-2011
+ * Graeme Russ, <graeme.russ@gmail.com>
+ *
+ * (C) Copyright 2002
+ * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/interrupt.h>
+#include <asm/ic/sc520.h>
+
+void sc520_timer_isr(void)
+{
+ /* Ack the GP Timer Interrupt */
+ writeb(0x02, &sc520_mmcr->gptmrsta);
+}
+
+int timer_init(void)
+{
+ /* Register the SC520 specific timer interrupt handler */
+ register_timer_isr (sc520_timer_isr);
+
+ /* Install interrupt handler for GP Timer 1 */
+ irq_install_handler (0, timer_isr, NULL);
+
+ /* Map GP Timer 1 to Master PIC IR0 */
+ writeb(0x01, &sc520_mmcr->gp_tmr_int_map[1]);
+
+ /* Disable GP Timers 1 & 2 - Allow configuration writes */
+ writew(0x4000, &sc520_mmcr->gptmr1ctl);
+ writew(0x4000, &sc520_mmcr->gptmr2ctl);
+
+ /* Reset GP Timers 1 & 2 */
+ writew(0x0000, &sc520_mmcr->gptmr1cnt);
+ writew(0x0000, &sc520_mmcr->gptmr2cnt);
+
+ /* Setup GP Timer 2 as a 100kHz (10us) prescaler */
+ writew(83, &sc520_mmcr->gptmr2maxcmpa);
+ writew(0xc001, &sc520_mmcr->gptmr2ctl);
+
+ /* Setup GP Timer 1 as a 1000 Hz (1ms) interrupt generator */
+ writew(100, &sc520_mmcr->gptmr1maxcmpa);
+ writew(0xe009, &sc520_mmcr->gptmr1ctl);
+
+ unmask_irq (0);
+
+ /* Clear the GP Timer 1 status register to get the show rolling*/
+ writeb(0x02, &sc520_mmcr->gptmrsta);
+
+ return 0;
+}
+
+/* Allow boards to override udelay implementation */
+void __udelay(unsigned long usec)
+ __attribute__((weak, alias("sc520_udelay")));
+
+void sc520_udelay(unsigned long usec)
+{
+ int m = 0;
+ long u;
+ long temp;
+
+ temp = readw(&sc520_mmcr->swtmrmilli);
+ temp = readw(&sc520_mmcr->swtmrmicro);
+
+ do {
+ m += readw(&sc520_mmcr->swtmrmilli);
+ u = readw(&sc520_mmcr->swtmrmicro) + (m * 1000);
+ } while (u < usec);
+}
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