[MIPS] time: Add GT641xx timer0 clockevent driver
authorYoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Mon, 22 Oct 2007 10:43:15 +0000 (19:43 +0900)
committerRalf Baechle <ralf@linux-mips.org>
Mon, 22 Oct 2007 21:09:00 +0000 (22:09 +0100)
And make use of it for Cobalt.  A few others such as the Malta could make
use of it as well.

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/Kconfig
arch/mips/cobalt/Makefile
arch/mips/cobalt/setup.c
arch/mips/cobalt/time.c [new file with mode: 0644]
arch/mips/kernel/Makefile
arch/mips/kernel/cevt-gt641xx.c [new file with mode: 0644]
include/asm-mips/gt64120.h

index 3ecff5e..61262c5 100644 (file)
@@ -66,6 +66,7 @@ config BCM47XX
 config MIPS_COBALT
        bool "Cobalt Server"
        select CEVT_R4K
+       select CEVT_GT641XX
        select DMA_NONCOHERENT
        select HW_HAS_PCI
        select I8253
@@ -729,6 +730,9 @@ config ARCH_MAY_HAVE_PC_FDC
 config BOOT_RAW
        bool
 
+config CEVT_GT641XX
+       bool
+
 config CEVT_R4K
        bool
 
index 6b83f4d..d73833b 100644 (file)
@@ -2,7 +2,7 @@
 # Makefile for the Cobalt micro systems family specific parts of the kernel
 #
 
-obj-y := buttons.o irq.o led.o reset.o rtc.o serial.o setup.o
+obj-y := buttons.o irq.o led.o reset.o rtc.o serial.o setup.o time.o
 
 obj-$(CONFIG_PCI)              += pci.o
 obj-$(CONFIG_EARLY_PRINTK)     += console.o
index d11bb1b..dd23beb 100644 (file)
@@ -9,19 +9,17 @@
  * Copyright (C) 2001, 2002, 2003 by Liam Davies (ldavies@agile.tv)
  *
  */
-#include <linux/interrupt.h>
 #include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
 #include <linux/pm.h>
 
 #include <asm/bootinfo.h>
-#include <asm/time.h>
-#include <asm/i8253.h>
-#include <asm/io.h>
 #include <asm/reboot.h>
 #include <asm/gt64120.h>
 
 #include <cobalt.h>
-#include <irq.h>
 
 extern void cobalt_machine_restart(char *command);
 extern void cobalt_machine_halt(void);
@@ -41,17 +39,6 @@ const char *get_system_type(void)
        return "MIPS Cobalt";
 }
 
-void __init plat_timer_setup(struct irqaction *irq)
-{
-       /* Load timer value for HZ (TCLK is 50MHz) */
-       GT_WRITE(GT_TC0_OFS, 50*1000*1000 / HZ);
-
-       /* Enable timer0 */
-       GT_WRITE(GT_TC_CONTROL_OFS, GT_TC_CONTROL_ENTC0_MSK | GT_TC_CONTROL_SELTC0_MSK);
-
-       setup_irq(GT641XX_TIMER0_IRQ, irq);
-}
-
 /*
  * Cobalt doesn't have PS/2 keyboard/mouse interfaces,
  * keyboard conntroller is never used.
@@ -84,11 +71,6 @@ static struct resource cobalt_reserved_resources[] = {
        },
 };
 
-void __init plat_time_init(void)
-{
-       setup_pit_timer();
-}
-
 void __init plat_mem_setup(void)
 {
        int i;
diff --git a/arch/mips/cobalt/time.c b/arch/mips/cobalt/time.c
new file mode 100644 (file)
index 0000000..fa819fc
--- /dev/null
@@ -0,0 +1,35 @@
+/*
+ *  Cobalt time initialization.
+ *
+ *  Copyright (C) 2007  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/init.h>
+
+#include <asm/gt64120.h>
+#include <asm/i8253.h>
+#include <asm/time.h>
+
+#define GT641XX_BASE_CLOCK     50000000        /* 50MHz */
+
+void __init plat_time_init(void)
+{
+       setup_pit_timer();
+
+       gt641xx_set_base_clock(GT641XX_BASE_CLOCK);
+
+       mips_timer_state = gt641xx_timer0_state;
+}
index a3afa39..d7745c8 100644 (file)
@@ -9,6 +9,7 @@ obj-y           += cpu-probe.o branch.o entry.o genex.o irq.o process.o \
                   time.o topology.o traps.o unaligned.o
 
 obj-$(CONFIG_CEVT_R4K)         += cevt-r4k.o
+obj-$(CONFIG_CEVT_GT641XX)     += cevt-gt641xx.o
 
 binfmt_irix-objs       := irixelf.o irixinv.o irixioctl.o irixsig.o    \
                           irix5sys.o sysirix.o
diff --git a/arch/mips/kernel/cevt-gt641xx.c b/arch/mips/kernel/cevt-gt641xx.c
new file mode 100644 (file)
index 0000000..4c651b2
--- /dev/null
@@ -0,0 +1,144 @@
+/*
+ *  GT641xx clockevent routines.
+ *
+ *  Copyright (C) 2007  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/clockchips.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+
+#include <asm/gt64120.h>
+#include <asm/time.h>
+
+#include <irq.h>
+
+static DEFINE_SPINLOCK(gt641xx_timer_lock);
+static unsigned int gt641xx_base_clock;
+
+void gt641xx_set_base_clock(unsigned int clock)
+{
+       gt641xx_base_clock = clock;
+}
+
+int gt641xx_timer0_state(void)
+{
+       if (GT_READ(GT_TC0_OFS))
+               return 0;
+
+       GT_WRITE(GT_TC0_OFS, gt641xx_base_clock / HZ);
+       GT_WRITE(GT_TC_CONTROL_OFS, GT_TC_CONTROL_ENTC0_MSK);
+
+       return 1;
+}
+
+static int gt641xx_timer0_set_next_event(unsigned long delta,
+                                        struct clock_event_device *evt)
+{
+       unsigned long flags;
+       u32 ctrl;
+
+       spin_lock_irqsave(&gt641xx_timer_lock, flags);
+
+       ctrl = GT_READ(GT_TC_CONTROL_OFS);
+       ctrl &= ~(GT_TC_CONTROL_ENTC0_MSK | GT_TC_CONTROL_SELTC0_MSK);
+       ctrl |= GT_TC_CONTROL_ENTC0_MSK;
+
+       GT_WRITE(GT_TC0_OFS, delta);
+       GT_WRITE(GT_TC_CONTROL_OFS, ctrl);
+
+       spin_unlock_irqrestore(&gt641xx_timer_lock, flags);
+
+       return 0;
+}
+
+static void gt641xx_timer0_set_mode(enum clock_event_mode mode,
+                                   struct clock_event_device *evt)
+{
+       unsigned long flags;
+       u32 ctrl;
+
+       spin_lock_irqsave(&gt641xx_timer_lock, flags);
+
+       ctrl = GT_READ(GT_TC_CONTROL_OFS);
+       ctrl &= ~(GT_TC_CONTROL_ENTC0_MSK | GT_TC_CONTROL_SELTC0_MSK);
+
+       switch (mode) {
+       case CLOCK_EVT_MODE_PERIODIC:
+               ctrl |= GT_TC_CONTROL_ENTC0_MSK | GT_TC_CONTROL_SELTC0_MSK;
+               break;
+       case CLOCK_EVT_MODE_ONESHOT:
+               ctrl |= GT_TC_CONTROL_ENTC0_MSK;
+               break;
+       default:
+               break;
+       }
+
+       GT_WRITE(GT_TC_CONTROL_OFS, ctrl);
+
+       spin_unlock_irqrestore(&gt641xx_timer_lock, flags);
+}
+
+static void gt641xx_timer0_event_handler(struct clock_event_device *dev)
+{
+}
+
+static struct clock_event_device gt641xx_timer0_clockevent = {
+       .name           = "gt641xx-timer0",
+       .features       = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+       .cpumask        = CPU_MASK_CPU0,
+       .irq            = GT641XX_TIMER0_IRQ,
+       .set_next_event = gt641xx_timer0_set_next_event,
+       .set_mode       = gt641xx_timer0_set_mode,
+       .event_handler  = gt641xx_timer0_event_handler,
+};
+
+static irqreturn_t gt641xx_timer0_interrupt(int irq, void *dev_id)
+{
+       struct clock_event_device *cd = &gt641xx_timer0_clockevent;
+
+       cd->event_handler(cd);
+
+       return IRQ_HANDLED;
+}
+
+static struct irqaction gt641xx_timer0_irqaction = {
+       .handler        = gt641xx_timer0_interrupt,
+       .flags          = IRQF_DISABLED | IRQF_PERCPU,
+       .name           = "gt641xx_timer0",
+};
+
+static int __init gt641xx_timer0_clockevent_init(void)
+{
+       struct clock_event_device *cd;
+
+       if (!gt641xx_base_clock)
+               return 0;
+
+       GT_WRITE(GT_TC0_OFS, gt641xx_base_clock / HZ);
+
+       cd = &gt641xx_timer0_clockevent;
+       cd->rating = 200 + gt641xx_base_clock / 10000000;
+       cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd);
+       cd->min_delta_ns = clockevent_delta2ns(0x300, cd);
+       clockevent_set_clock(cd, gt641xx_base_clock);
+
+       clockevents_register_device(&gt641xx_timer0_clockevent);
+
+       return setup_irq(GT641XX_TIMER0_IRQ, &gt641xx_timer0_irqaction);
+}
+arch_initcall(gt641xx_timer0_clockevent_init);
index 4bf8e28..e64b410 100644 (file)
@@ -21,6 +21,8 @@
 #ifndef _ASM_GT64120_H
 #define _ASM_GT64120_H
 
+#include <linux/clocksource.h>
+
 #include <asm/addrspace.h>
 #include <asm/byteorder.h>
 
 #define GT_READ(ofs)           le32_to_cpu(__GT_READ(ofs))
 #define GT_WRITE(ofs, data)    __GT_WRITE(ofs, cpu_to_le32(data))
 
+extern void gt641xx_set_base_clock(unsigned int clock);
+extern int gt641xx_timer0_state(void);
+
 #endif /* _ASM_GT64120_H */