[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>

2 files changed, 23 insertions, 22 deletions

diff --git a/arch/m68knommu/platform/5307/pit.c b/arch/m68knommu/platform/5307/pit.c
index 323f2677e49d..ef174748825f 100644
--- 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 0d2672dd518a..f570cf64fd29 100644
--- 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.