[MIPS] add DECstation I/O ASIC clocksource
Add DECstation I/O ASIC clocksource
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 77e3d24..2e4ac65 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -82,6 +82,7 @@
bool "DECstations"
select BOOT_ELF32
select CEVT_R4K
+ select CSRC_IOASIC
select CSRC_R4K
select CPU_DADDI_WORKAROUNDS if 64BIT
select CPU_R4000_WORKAROUNDS if 64BIT
@@ -784,6 +785,9 @@
config CSRC_BCM1480
bool
+config CSRC_IOASIC
+ bool
+
config CSRC_R4K
bool
diff --git a/arch/mips/dec/time.c b/arch/mips/dec/time.c
index 6034906..0cbab8d 100644
--- a/arch/mips/dec/time.c
+++ b/arch/mips/dec/time.c
@@ -165,7 +165,7 @@
if (!cpu_has_counter && IOASIC)
/* For pre-R4k systems we use the I/O ASIC's counter. */
- clocksource_mips.read = dec_ioasic_hpt_read;
+ dec_ioasic_clocksource_init();
/* Set up the rate of periodic DS1287 interrupts. */
CMOS_WRITE(RTC_REF_CLCK_32KHZ | (16 - __ffs(HZ)), RTC_REG_A);
diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
index 87067e8..00ac35e 100644
--- a/arch/mips/kernel/Makefile
+++ b/arch/mips/kernel/Makefile
@@ -14,6 +14,7 @@
obj-$(CONFIG_CEVT_SB1250) += cevt-sb1250.o
obj-$(CONFIG_CEVT_TXX9) += cevt-txx9.o
obj-$(CONFIG_CSRC_BCM1480) += csrc-bcm1480.o
+obj-$(CONFIG_CSRC_IOASIC) += csrc-ioasic.o
obj-$(CONFIG_CSRC_R4K) += csrc-r4k.o
obj-$(CONFIG_CSRC_SB1250) += csrc-sb1250.o
obj-$(CONFIG_SYNC_R4K) += sync-r4k.o
diff --git a/arch/mips/kernel/csrc-ioasic.c b/arch/mips/kernel/csrc-ioasic.c
new file mode 100644
index 0000000..1d5f63c
--- /dev/null
+++ b/arch/mips/kernel/csrc-ioasic.c
@@ -0,0 +1,65 @@
+/*
+ * DEC I/O ASIC's counter clocksource
+ *
+ * Copyright (C) 2008 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
+ *
+ * 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
+ */
+#include <linux/clocksource.h>
+#include <linux/init.h>
+
+#include <asm/ds1287.h>
+#include <asm/time.h>
+#include <asm/dec/ioasic.h>
+#include <asm/dec/ioasic_addrs.h>
+
+static cycle_t dec_ioasic_hpt_read(void)
+{
+ return ioasic_read(IO_REG_FCTR);
+}
+
+static struct clocksource clocksource_dec = {
+ .name = "dec-ioasic",
+ .read = dec_ioasic_hpt_read,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+void __init dec_ioasic_clocksource_init(void)
+{
+ unsigned int freq;
+ u32 start, end;
+ int i = HZ / 10;
+
+
+ while (!ds1287_timer_state())
+ ;
+
+ start = dec_ioasic_hpt_read();
+
+ while (i--)
+ while (!ds1287_timer_state())
+ ;
+
+ end = dec_ioasic_hpt_read();
+
+ freq = (end - start) * 10;
+ printk(KERN_INFO "I/O ASIC clock frequency %dHz\n", freq);
+
+ clocksource_dec.rating = 200 + freq / 10000000;
+ clocksource_set_clock(&clocksource_dec, freq);
+
+ clocksource_register(&clocksource_dec);
+}
diff --git a/include/asm-mips/dec/ioasic.h b/include/asm-mips/dec/ioasic.h
index 486a5b0..98badd6 100644
--- a/include/asm-mips/dec/ioasic.h
+++ b/include/asm-mips/dec/ioasic.h
@@ -33,4 +33,6 @@
extern void init_ioasic_irqs(int base);
+extern void dec_ioasic_clocksource_init(void);
+
#endif /* __ASM_DEC_IOASIC_H */