From 6457d9fc3bb87c72db03cfb34cd414c8fb9b8edf Mon Sep 17 00:00:00 2001 From: Yoichi Yuasa Date: Fri, 25 Apr 2008 12:11:44 +0900 Subject: [PATCH] [MIPS] DS1287: Add clockevent driver Signed-off-by: Yoichi Yuasa Signed-off-by: Ralf Baechle --- arch/mips/Kconfig | 4 + arch/mips/dec/time.c | 73 ++++++------------- arch/mips/kernel/Makefile | 1 + arch/mips/kernel/cevt-ds1287.c | 129 +++++++++++++++++++++++++++++++++ include/asm-mips/ds1287.h | 27 +++++++ 5 files changed, 185 insertions(+), 49 deletions(-) create mode 100644 arch/mips/kernel/cevt-ds1287.c create mode 100644 include/asm-mips/ds1287.h diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 2e4ac657a4c3..e5a7c5d96364 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -81,6 +81,7 @@ config MIPS_COBALT config MACH_DECSTATION bool "DECstations" select BOOT_ELF32 + select CEVT_DS1287 select CEVT_R4K select CSRC_IOASIC select CSRC_R4K @@ -770,6 +771,9 @@ config BOOT_RAW config CEVT_BCM1480 bool +config CEVT_DS1287 + bool + config CEVT_GT641XX bool diff --git a/arch/mips/dec/time.c b/arch/mips/dec/time.c index 0cbab8d0052b..3965fda94a89 100644 --- a/arch/mips/dec/time.c +++ b/arch/mips/dec/time.c @@ -9,30 +9,15 @@ * */ #include -#include #include -#include -#include #include -#include -#include #include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include +#include +#include #include - #include #include -#include #include unsigned long read_persistent_clock(void) @@ -139,42 +124,32 @@ int rtc_mips_set_mmss(unsigned long nowtime) return retval; } -static int dec_timer_state(void) -{ - return (CMOS_READ(RTC_REG_C) & RTC_PF) != 0; -} - -static void dec_timer_ack(void) -{ - CMOS_READ(RTC_REG_C); /* Ack the RTC interrupt. */ -} - -static cycle_t dec_ioasic_hpt_read(void) -{ - /* - * The free-running counter is 32-bit which is good for about - * 2 minutes, 50 seconds at possible count rates of up to 25MHz. - */ - return ioasic_read(IO_REG_FCTR); -} - - void __init plat_time_init(void) { - mips_timer_ack = dec_timer_ack; + u32 start, end; + int i = HZ / 10; - if (!cpu_has_counter && IOASIC) + /* Set up the rate of periodic DS1287 interrupts. */ + ds1287_set_base_clock(HZ); + + if (cpu_has_counter) { + while (!ds1287_timer_state()) + ; + + start = read_c0_count(); + + while (i--) + while (!ds1287_timer_state()) + ; + + end = read_c0_count(); + + mips_hpt_frequency = (end - start) * 10; + printk(KERN_INFO "MIPS counter frequency %dHz\n", + mips_hpt_frequency); + } else if (IOASIC) /* For pre-R4k systems we use the I/O ASIC's counter. */ dec_ioasic_clocksource_init(); - /* Set up the rate of periodic DS1287 interrupts. */ - CMOS_WRITE(RTC_REF_CLCK_32KHZ | (16 - __ffs(HZ)), RTC_REG_A); -} - -void __init plat_timer_setup(struct irqaction *irq) -{ - setup_irq(dec_interrupt[DEC_IRQ_RTC], irq); - - /* Enable periodic DS1287 interrupts. */ - CMOS_WRITE(CMOS_READ(RTC_REG_B) | RTC_PIE, RTC_REG_B); + ds1287_clockevent_init(dec_interrupt[DEC_IRQ_RTC]); } diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile index 00ac35e501b3..45545be3eb86 100644 --- a/arch/mips/kernel/Makefile +++ b/arch/mips/kernel/Makefile @@ -10,6 +10,7 @@ obj-y += cpu-probe.o branch.o entry.o genex.o irq.o process.o \ obj-$(CONFIG_CEVT_BCM1480) += cevt-bcm1480.o obj-$(CONFIG_CEVT_R4K) += cevt-r4k.o +obj-$(CONFIG_CEVT_DS1287) += cevt-ds1287.o obj-$(CONFIG_CEVT_GT641XX) += cevt-gt641xx.o obj-$(CONFIG_CEVT_SB1250) += cevt-sb1250.o obj-$(CONFIG_CEVT_TXX9) += cevt-txx9.o diff --git a/arch/mips/kernel/cevt-ds1287.c b/arch/mips/kernel/cevt-ds1287.c new file mode 100644 index 000000000000..df4acb68bfb5 --- /dev/null +++ b/arch/mips/kernel/cevt-ds1287.c @@ -0,0 +1,129 @@ +/* + * DS1287 clockevent driver + * + * Copyright (C) 2008 Yoichi Yuasa + * + * 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 +#include +#include +#include + +#include + +int ds1287_timer_state(void) +{ + return (CMOS_READ(RTC_REG_C) & RTC_PF) != 0; +} + +int ds1287_set_base_clock(unsigned int hz) +{ + u8 rate; + + switch (hz) { + case 128: + rate = 0x9; + break; + case 256: + rate = 0x8; + break; + case 1024: + rate = 0x6; + break; + default: + return -EINVAL; + } + + CMOS_WRITE(RTC_REF_CLCK_32KHZ | rate, RTC_REG_A); + + return 0; +} + +static int ds1287_set_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + return -EINVAL; +} + +static void ds1287_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + u8 val; + + spin_lock(&rtc_lock); + + val = CMOS_READ(RTC_REG_B); + + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + val |= RTC_PIE; + break; + default: + val &= ~RTC_PIE; + break; + } + + CMOS_WRITE(val, RTC_REG_B); + + spin_unlock(&rtc_lock); +} + +static void ds1287_event_handler(struct clock_event_device *dev) +{ +} + +static struct clock_event_device ds1287_clockevent = { + .name = "ds1287", + .features = CLOCK_EVT_FEAT_PERIODIC, + .cpumask = CPU_MASK_CPU0, + .set_next_event = ds1287_set_next_event, + .set_mode = ds1287_set_mode, + .event_handler = ds1287_event_handler, +}; + +static irqreturn_t ds1287_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *cd = &ds1287_clockevent; + + /* Ack the RTC interrupt. */ + CMOS_READ(RTC_REG_C); + + cd->event_handler(cd); + + return IRQ_HANDLED; +} + +static struct irqaction ds1287_irqaction = { + .handler = ds1287_interrupt, + .flags = IRQF_DISABLED | IRQF_PERCPU, + .name = "ds1287", +}; + +int __init ds1287_clockevent_init(int irq) +{ + struct clock_event_device *cd; + + cd = &ds1287_clockevent; + cd->rating = 100; + cd->irq = irq; + clockevent_set_clock(cd, 32768); + cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd); + cd->min_delta_ns = clockevent_delta2ns(0x300, cd); + + clockevents_register_device(&ds1287_clockevent); + + return setup_irq(irq, &ds1287_irqaction); +} diff --git a/include/asm-mips/ds1287.h b/include/asm-mips/ds1287.h new file mode 100644 index 000000000000..ba1702e86931 --- /dev/null +++ b/include/asm-mips/ds1287.h @@ -0,0 +1,27 @@ +/* + * DS1287 timer functions. + * + * Copyright (C) 2008 Yoichi Yuasa + * + * 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 + */ +#ifndef __ASM_DS1287_H +#define __ASM_DS1287_H + +extern int ds1287_timer_state(void); +extern void ds1287_set_base_clock(unsigned int clock); +extern int ds1287_clockevent_init(int irq); + +#endif