[PATCH] m68knommu: read/write register access for PIT timer

Modify the m68knommu/ColdFire PIT timer code to use register offsets
with raw_read/raw_write access, instead of a mapped struct.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/arch/m68knommu/platform/5307/pit.c b/arch/m68knommu/platform/5307/pit.c
index 323f267..ef17474 100644 (file)
--- a/arch/m68knommu/platform/5307/pit.c
+++ b/arch/m68knommu/platform/5307/pit.c
@@ -1,11 +1,11 @@
 /***************************************************************************/
 
 /*
- *     pit.c -- Motorola ColdFire PIT timer. Currently this type of
- *              hardware timer only exists in the Motorola ColdFire
+ *     pit.c -- Freescale ColdFire PIT timer. Currently this type of
+ *              hardware timer only exists in the Freescale ColdFire
  *              5270/5271, 5282 and other CPUs.
  *
- *     Copyright (C) 1999-2004, Greg Ungerer (gerg@snapgear.com)
+ *     Copyright (C) 1999-2006, Greg Ungerer (gerg@snapgear.com)
  *     Copyright (C) 2001-2004, SnapGear Inc. (www.snapgear.com)
  *
  */
@@ -18,6 +18,7 @@
 #include <linux/param.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
+#include <asm/io.h>
 #include <asm/irq.h>
 #include <asm/coldfire.h>
 #include <asm/mcfpit.h>
@@ -25,13 +26,20 @@
 
 /***************************************************************************/
 
+/*
+ *     By default use timer1 as the system clock timer.
+ */
+#define        TA(a)   (MCF_IPSBAR + MCFPIT_BASE1 + (a))
+
+/***************************************************************************/
+
 void coldfire_pit_tick(void)
 {
-       volatile struct mcfpit *tp;
+       unsigned short pcsr;
 
        /* Reset the ColdFire timer */
-       tp = (volatile struct mcfpit *) (MCF_IPSBAR + MCFPIT_BASE1);
-       tp->pcsr |= MCFPIT_PCSR_PIF;
+       pcsr = __raw_readw(TA(MCFPIT_PCSR));
+       __raw_writew(pcsr | MCFPIT_PCSR_PIF, TA(MCFPIT_PCSR));
 }
 
 /***************************************************************************/
@@ -40,7 +48,6 @@ void coldfire_pit_init(irqreturn_t (*handler)(int, void *, struct pt_regs *))
 {
        volatile unsigned char *icrp;
        volatile unsigned long *imrp;
-       volatile struct mcfpit *tp;
 
        request_irq(MCFINT_VECBASE + MCFINT_PIT1, handler, SA_INTERRUPT,
                "ColdFire Timer", NULL);
@@ -53,27 +60,23 @@ void coldfire_pit_init(irqreturn_t (*handler)(int, void *, struct pt_regs *))
        *imrp &= ~MCFPIT_IMR_IBIT;
 
        /* Set up PIT timer 1 as poll clock */
-       tp = (volatile struct mcfpit *) (MCF_IPSBAR + MCFPIT_BASE1);
-       tp->pcsr = MCFPIT_PCSR_DISABLE;
-
-       tp->pmr = ((MCF_CLK / 2) / 64) / HZ;
-       tp->pcsr = MCFPIT_PCSR_EN | MCFPIT_PCSR_PIE | MCFPIT_PCSR_OVW |
-               MCFPIT_PCSR_RLD | MCFPIT_PCSR_CLK64;
+       __raw_writew(MCFPIT_PCSR_DISABLE, TA(MCFPIT_PCSR));
+       __raw_writew(((MCF_CLK / 2) / 64) / HZ, TA(MCFPIT_PMR));
+       __raw_writew(MCFPIT_PCSR_EN | MCFPIT_PCSR_PIE | MCFPIT_PCSR_OVW |
+               MCFPIT_PCSR_RLD | MCFPIT_PCSR_CLK64, TA(MCFPIT_PCSR));
 }
 
 /***************************************************************************/
 
 unsigned long coldfire_pit_offset(void)
 {
-       volatile struct mcfpit *tp;
        volatile unsigned long *ipr;
        unsigned long pmr, pcntr, offset;
 
-       tp = (volatile struct mcfpit *) (MCF_IPSBAR + MCFPIT_BASE1);
        ipr = (volatile unsigned long *) (MCF_IPSBAR + MCFICM_INTC0 + MCFPIT_IMR);
 
-       pmr = *(&tp->pmr);
-       pcntr = *(&tp->pcntr);
+       pmr = __raw_readw(TA(MCFPIT_PMR));
+       pcntr = __raw_readw(TA(MCFPIT_PCNTR));
 
        /*
         * If we are still in the first half of the upcount and a

diff --git a/include/asm-m68knommu/mcfpit.h b/include/asm-m68knommu/mcfpit.h
index 0d2672d..f570cf6 100644 (file)
--- a/include/asm-m68knommu/mcfpit.h
+++ b/include/asm-m68knommu/mcfpit.h
@@ -28,11 +28,9 @@
 /*
  *     Define the PIT timer register set addresses.
  */
-struct mcfpit {
-       unsigned short  pcsr;                   /* PIT control and status */
-       unsigned short  pmr;                    /* PIT modulus register */
-       unsigned short  pcntr;                  /* PIT count register */
-} __attribute__((packed));
+#define        MCFPIT_PCSR             0x0             /* PIT control register */
+#define        MCFPIT_PMR              0x2             /* PIT modulus register */
+#define        MCFPIT_PCNTR            0x4             /* PIT count register */
 
 /*
  *     Bit definitions for the PIT Control and Status register.