[ARM] 3822/1: iop3xx: rewrite time handling

Merge and rewrite the iop32x/iop33x time code to do lost jiffy
tracking properly, and put the result in plat-iop/time.c.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/plat-iop/Makefile b/arch/arm/plat-iop/Makefile
index efde7a513fb718c5e6f0e1567328c7a62cc79e53..d20cdec3a9447b6f9196424aaf2f2a0933bb695a 100644 (file)
--- a/arch/arm/plat-iop/Makefile
+++ b/arch/arm/plat-iop/Makefile
@@ -2,7 +2,7 @@
 # Makefile for the linux kernel.
 #
 
-obj-y                  := i2c.o pci.o setup.o
+obj-y                  := i2c.o pci.o setup.o time.o
 obj-m                  :=
 obj-n                  :=
 obj-                   :=

diff --git a/arch/arm/plat-iop/time.c b/arch/arm/plat-iop/time.c
new file mode 100644 (file)
index 0000000..5730a0d
--- /dev/null
+++ b/arch/arm/plat-iop/time.c
@@ -0,0 +1,94 @@
+/*
+ * arch/arm/plat-iop/time.c
+ *
+ * Timer code for IOP32x and IOP33x based systems
+ *
+ * Author: Deepak Saxena <dsaxena@mvista.com>
+ *
+ * Copyright 2002-2003 MontaVista Software Inc.
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/init.h>
+#include <linux/timex.h>
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+#ifdef CONFIG_ARCH_IOP32X
+#define IRQ_IOP3XX_TIMER0      IRQ_IOP321_TIMER0
+#else
+#ifdef CONFIG_ARCH_IOP33X
+#define IRQ_IOP3XX_TIMER0      IRQ_IOP331_TIMER0
+#endif
+#endif
+
+static unsigned long ticks_per_jiffy;
+static unsigned long ticks_per_usec;
+static unsigned long next_jiffy_time;
+
+unsigned long iop3xx_gettimeoffset(void)
+{
+       unsigned long offset;
+
+       offset = next_jiffy_time - *IOP3XX_TU_TCR1;
+
+       return offset / ticks_per_usec;
+}
+
+static irqreturn_t
+iop3xx_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+       write_seqlock(&xtime_lock);
+
+       asm volatile("mcr p6, 0, %0, c6, c1, 0" : : "r" (1));
+
+       while ((signed long)(next_jiffy_time - *IOP3XX_TU_TCR1)
+                                                       >= ticks_per_jiffy) {
+               timer_tick(regs);
+               next_jiffy_time -= ticks_per_jiffy;
+       }
+
+       write_sequnlock(&xtime_lock);
+
+       return IRQ_HANDLED;
+}
+
+static struct irqaction iop3xx_timer_irq = {
+       .name           = "IOP3XX Timer Tick",
+       .handler        = iop3xx_timer_interrupt,
+       .flags          = IRQF_DISABLED | IRQF_TIMER,
+};
+
+void __init iop3xx_init_time(unsigned long tick_rate)
+{
+       u32 timer_ctl;
+
+       ticks_per_jiffy = (tick_rate + HZ/2) / HZ;
+       ticks_per_usec = tick_rate / 1000000;
+       next_jiffy_time = 0xffffffff;
+
+       timer_ctl = IOP3XX_TMR_EN | IOP3XX_TMR_PRIVILEGED |
+                       IOP3XX_TMR_RELOAD | IOP3XX_TMR_RATIO_1_1;
+
+       /*
+        * We use timer 0 for our timer interrupt, and timer 1 as
+        * monotonic counter for tracking missed jiffies.
+        */
+       asm volatile("mcr p6, 0, %0, c4, c1, 0" : : "r" (ticks_per_jiffy - 1));
+       asm volatile("mcr p6, 0, %0, c0, c1, 0" : : "r" (timer_ctl));
+       asm volatile("mcr p6, 0, %0, c5, c1, 0" : : "r" (0xffffffff));
+       asm volatile("mcr p6, 0, %0, c1, c1, 0" : : "r" (timer_ctl));
+
+       setup_irq(IRQ_IOP3XX_TIMER0, &iop3xx_timer_irq);
+}

diff --git a/include/asm-arm/arch-iop32x/iop321.h b/include/asm-arm/arch-iop32x/iop321.h
index e3c85a05e73afa16d9b2cd00e61af904355d7b9b..bd96b8d55a76c4bdf29f60bcb28ff127fd5911f4 100644 (file)
--- a/include/asm-arm/arch-iop32x/iop321.h
+++ b/include/asm-arm/arch-iop32x/iop321.h
@@ -233,6 +233,12 @@
 
 /* for I2C bit defs see drivers/i2c/i2c-iop3xx.h */
 
+/*
+ * Peripherals that are shared between the iop32x and iop33x but
+ * located at different addresses.
+ */
+#define IOP3XX_TIMER_REG(reg)  (IOP3XX_PERIPHERAL_VIRT_BASE + 0x07e0 + (reg))
+
 #include <asm/hardware/iop3xx.h>
 
 

diff --git a/include/asm-arm/arch-iop33x/iop331.h b/include/asm-arm/arch-iop33x/iop331.h
index e85e1a2e1a868e1eeba36003d65e07049e26c455..b301ef8f7f32cfe7157cc2787ac9065d6d872a8e 100644 (file)
--- a/include/asm-arm/arch-iop33x/iop331.h
+++ b/include/asm-arm/arch-iop33x/iop331.h
@@ -238,6 +238,12 @@
 
 /* Reserved 0x0000178c through 0x000019ff */
 
+/*
+ * Peripherals that are shared between the iop32x and iop33x but
+ * located at different addresses.
+ */
+#define IOP3XX_TIMER_REG(reg)  (IOP3XX_PERIPHERAL_VIRT_BASE + 0x07d0 + (reg))
+
 #include <asm/hardware/iop3xx.h>
 
 

diff --git a/include/asm-arm/hardware/iop3xx.h b/include/asm-arm/hardware/iop3xx.h
index d488ced2e12d8935f08db46f1d47d14e5bffdef7..b21ea41b149e1a8ff5504769f46b39c92d33993d 100644 (file)
--- a/include/asm-arm/hardware/iop3xx.h
+++ b/include/asm-arm/hardware/iop3xx.h
@@ -81,6 +81,24 @@
 #define IOP3XX_PCIXSR          (volatile u32 *)IOP3XX_REG_ADDR(0x01e4)
 #define IOP3XX_PCIIRSR         (volatile u32 *)IOP3XX_REG_ADDR(0x01ec)
 
+/* Timers  */
+#define IOP3XX_TU_TMR0         (volatile u32 *)IOP3XX_TIMER_REG(0x0000)
+#define IOP3XX_TU_TMR1         (volatile u32 *)IOP3XX_TIMER_REG(0x0004)
+#define IOP3XX_TU_TCR0         (volatile u32 *)IOP3XX_TIMER_REG(0x0008)
+#define IOP3XX_TU_TCR1         (volatile u32 *)IOP3XX_TIMER_REG(0x000c)
+#define IOP3XX_TU_TRR0         (volatile u32 *)IOP3XX_TIMER_REG(0x0010)
+#define IOP3XX_TU_TRR1         (volatile u32 *)IOP3XX_TIMER_REG(0x0014)
+#define IOP3XX_TU_TISR         (volatile u32 *)IOP3XX_TIMER_REG(0x0018)
+#define IOP3XX_TU_WDTCR                (volatile u32 *)IOP3XX_TIMER_REG(0x001c)
+#define IOP3XX_TMR_TC          0x01
+#define IOP3XX_TMR_EN          0x02
+#define IOP3XX_TMR_RELOAD      0x04
+#define IOP3XX_TMR_PRIVILEGED  0x09
+#define IOP3XX_TMR_RATIO_1_1   0x00
+#define IOP3XX_TMR_RATIO_4_1   0x10
+#define IOP3XX_TMR_RATIO_8_1   0x20
+#define IOP3XX_TMR_RATIO_16_1  0x30
+
 /* I2C bus interface unit  */
 #define IOP3XX_ICR0            (volatile u32 *)IOP3XX_REG_ADDR(0x1680)
 #define IOP3XX_ISR0            (volatile u32 *)IOP3XX_REG_ADDR(0x1684)
@@ -109,6 +127,8 @@
 
 #ifndef __ASSEMBLY__
 void iop3xx_map_io(void);
+void iop3xx_init_time(unsigned long);
+unsigned long iop3xx_gettimeoffset(void);
 
 extern struct platform_device iop3xx_i2c0_device;
 extern struct platform_device iop3xx_i2c1_device;