[PATCH] ppc32 8xx: use io accessor macros instead of direct memory reference

Convert core 8xx drivers to use in_xxxbe/in_xxx macros instead of direct
memory references.

Other than making IO accesses explicit (which is a plus for readability), a
common set of macros provides a unified place for the volatile flag to
constraint compiler code reordering.

There are several unlucky places at the moment which lack the volatile
flag.

Signed-off-by: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

3 files changed, 34 insertions, 42 deletions

diff --git a/arch/ppc/syslib/m8xx_setup.c b/arch/ppc/syslib/m8xx_setup.c
index c88e2d4dceb..a192719929d 100644
--- a/arch/ppc/syslib/m8xx_setup.c
+++ b/arch/ppc/syslib/m8xx_setup.c
@@ -144,12 +144,12 @@ void __init m8xx_calibrate_decr(void)
 	int freq, fp, divisor;
 
 	/* Unlock the SCCR. */
-	((volatile immap_t *)IMAP_ADDR)->im_clkrstk.cark_sccrk = ~KAPWR_KEY;
-	((volatile immap_t *)IMAP_ADDR)->im_clkrstk.cark_sccrk = KAPWR_KEY;
+	out_be32(&((immap_t *)IMAP_ADDR)->im_clkrstk.cark_sccrk, ~KAPWR_KEY);
+	out_be32(&((immap_t *)IMAP_ADDR)->im_clkrstk.cark_sccrk, KAPWR_KEY);
 
 	/* Force all 8xx processors to use divide by 16 processor clock. */
-	((volatile immap_t *)IMAP_ADDR)->im_clkrst.car_sccr |= 0x02000000;
-
+	out_be32(&((immap_t *)IMAP_ADDR)->im_clkrst.car_sccr,
+		in_be32(&((immap_t *)IMAP_ADDR)->im_clkrst.car_sccr)|0x02000000);
 	/* Processor frequency is MHz.
 	 * The value 'fp' is the number of decrementer ticks per second.
 	 */
@@ -175,28 +175,24 @@ void __init m8xx_calibrate_decr(void)
 	 * we guarantee the registers are locked, then we unlock them
 	 * for our use.
 	 */
-	((volatile immap_t *)IMAP_ADDR)->im_sitk.sitk_tbscrk = ~KAPWR_KEY;
-	((volatile immap_t *)IMAP_ADDR)->im_sitk.sitk_rtcsck = ~KAPWR_KEY;
-	((volatile immap_t *)IMAP_ADDR)->im_sitk.sitk_tbk    = ~KAPWR_KEY;
-	((volatile immap_t *)IMAP_ADDR)->im_sitk.sitk_tbscrk =  KAPWR_KEY;
-	((volatile immap_t *)IMAP_ADDR)->im_sitk.sitk_rtcsck =  KAPWR_KEY;
-	((volatile immap_t *)IMAP_ADDR)->im_sitk.sitk_tbk    =  KAPWR_KEY;
+	out_be32(&((immap_t *)IMAP_ADDR)->im_sitk.sitk_tbscrk, ~KAPWR_KEY);
+	out_be32(&((immap_t *)IMAP_ADDR)->im_sitk.sitk_rtcsck, ~KAPWR_KEY);
+	out_be32(&((immap_t *)IMAP_ADDR)->im_sitk.sitk_tbk, ~KAPWR_KEY);
+	out_be32(&((immap_t *)IMAP_ADDR)->im_sitk.sitk_tbscrk, KAPWR_KEY);
+	out_be32(&((immap_t *)IMAP_ADDR)->im_sitk.sitk_rtcsck, KAPWR_KEY);
+	out_be32(&((immap_t *)IMAP_ADDR)->im_sitk.sitk_tbk, KAPWR_KEY);
 
 	/* Disable the RTC one second and alarm interrupts. */
-	((volatile immap_t *)IMAP_ADDR)->im_sit.sit_rtcsc &=
-						~(RTCSC_SIE | RTCSC_ALE);
+	out_be16(&((immap_t *)IMAP_ADDR)->im_sit.sit_rtcsc, in_be16(&((immap_t *)IMAP_ADDR)->im_sit.sit_rtcsc) & ~(RTCSC_SIE | RTCSC_ALE));
 	/* Enable the RTC */
-	((volatile immap_t *)IMAP_ADDR)->im_sit.sit_rtcsc |=
-						(RTCSC_RTF | RTCSC_RTE);
+	out_be16(&((immap_t *)IMAP_ADDR)->im_sit.sit_rtcsc, in_be16(&((immap_t *)IMAP_ADDR)->im_sit.sit_rtcsc) | (RTCSC_RTF | RTCSC_RTE));
 
 	/* Enabling the decrementer also enables the timebase interrupts
 	 * (or from the other point of view, to get decrementer interrupts
 	 * we have to enable the timebase).  The decrementer interrupt
 	 * is wired into the vector table, nothing to do here for that.
 	 */
-	((volatile immap_t *)IMAP_ADDR)->im_sit.sit_tbscr =
-				((mk_int_int_mask(DEC_INTERRUPT) << 8) |
-					 (TBSCR_TBF | TBSCR_TBE));
+	out_be16(&((immap_t *)IMAP_ADDR)->im_sit.sit_tbscr, (mk_int_int_mask(DEC_INTERRUPT) << 8) | (TBSCR_TBF | TBSCR_TBE));
 
 	if (setup_irq(DEC_INTERRUPT, &tbint_irqaction))
 		panic("Could not allocate timer IRQ!");
@@ -216,9 +212,9 @@ void __init m8xx_calibrate_decr(void)
 static int
 m8xx_set_rtc_time(unsigned long time)
 {
-	((volatile immap_t *)IMAP_ADDR)->im_sitk.sitk_rtck = KAPWR_KEY;
-	((volatile immap_t *)IMAP_ADDR)->im_sit.sit_rtc = time;
-	((volatile immap_t *)IMAP_ADDR)->im_sitk.sitk_rtck = ~KAPWR_KEY;
+	out_be32(&((immap_t *)IMAP_ADDR)->im_sitk.sitk_rtck, KAPWR_KEY);
+	out_be32(&((immap_t *)IMAP_ADDR)->im_sit.sit_rtc, time);
+	out_be32(&((immap_t *)IMAP_ADDR)->im_sitk.sitk_rtck, ~KAPWR_KEY);
 	return(0);
 }
 
@@ -226,7 +222,7 @@ static unsigned long
 m8xx_get_rtc_time(void)
 {
 	/* Get time from the RTC. */
-	return((unsigned long)(((immap_t *)IMAP_ADDR)->im_sit.sit_rtc));
+	return (unsigned long) in_be32(&((immap_t *)IMAP_ADDR)->im_sit.sit_rtc);
 }
 
 static void
@@ -235,13 +231,13 @@ m8xx_restart(char *cmd)
 	__volatile__ unsigned char dummy;
 
 	local_irq_disable();
-	((immap_t *)IMAP_ADDR)->im_clkrst.car_plprcr |= 0x00000080;
+	out_be32(&((immap_t *)IMAP_ADDR)->im_clkrst.car_plprcr, in_be32(&((immap_t *)IMAP_ADDR)->im_clkrst.car_plprcr) | 0x00000080);
 
 	/* Clear the ME bit in MSR to cause checkstop on machine check
 	*/
 	mtmsr(mfmsr() & ~0x1000);
 
-	dummy = ((immap_t *)IMAP_ADDR)->im_clkrst.res[0];
+	dummy = in_8(&((immap_t *)IMAP_ADDR)->im_clkrst.res[0]);
 	printk("Restart failed\n");
 	while(1);
 }
@@ -306,8 +302,7 @@ m8xx_init_IRQ(void)
 	i8259_init(0);
 
 	/* The i8259 cascade interrupt must be level sensitive. */
-	((immap_t *)IMAP_ADDR)->im_siu_conf.sc_siel &=
-		~(0x80000000 >> ISA_BRIDGE_INT);
+	out_be32(&((immap_t *)IMAP_ADDR)->im_siu_conf.sc_siel, in_be32(&((immap_t *)IMAP_ADDR)->im_siu_conf.sc_siel & ~(0x80000000 >> ISA_BRIDGE_INT)));
 
 	if (setup_irq(ISA_BRIDGE_INT, &mbx_i8259_irqaction))
 		enable_irq(ISA_BRIDGE_INT);
diff --git a/arch/ppc/syslib/m8xx_wdt.c b/arch/ppc/syslib/m8xx_wdt.c
index 2ddc857e7fc..c5ac5ce5d7d 100644
--- a/arch/ppc/syslib/m8xx_wdt.c
+++ b/arch/ppc/syslib/m8xx_wdt.c
@@ -29,8 +29,8 @@ void m8xx_wdt_reset(void)
 {
 	volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR;
 
-	imap->im_siu_conf.sc_swsr = 0x556c;	/* write magic1 */
-	imap->im_siu_conf.sc_swsr = 0xaa39;	/* write magic2 */
+	out_be16(imap->im_siu_conf.sc_swsr, 0x556c);	/* write magic1 */
+	out_be16(imap->im_siu_conf.sc_swsr, 0xaa39);	/* write magic2 */
 }
 
 static irqreturn_t m8xx_wdt_interrupt(int irq, void *dev, struct pt_regs *regs)
@@ -39,7 +39,7 @@ static irqreturn_t m8xx_wdt_interrupt(int irq, void *dev, struct pt_regs *regs)
 
 	m8xx_wdt_reset();
 
-	imap->im_sit.sit_piscr |= PISCR_PS;	/* clear irq */
+	out_be16(imap->im_sit.sit_piscr, in_be16(imap->im_sit.sit_piscr | PISCR_PS));	/* clear irq */
 
 	return IRQ_HANDLED;
 }
@@ -51,7 +51,7 @@ void __init m8xx_wdt_handler_install(bd_t * binfo)
 	u32 sypcr;
 	u32 pitrtclk;
 
-	sypcr = imap->im_siu_conf.sc_sypcr;
+	sypcr = in_be32(imap->im_siu_conf.sc_sypcr);
 
 	if (!(sypcr & 0x04)) {
 		printk(KERN_NOTICE "m8xx_wdt: wdt disabled (SYPCR: 0x%08X)\n",
@@ -87,9 +87,9 @@ void __init m8xx_wdt_handler_install(bd_t * binfo)
 	else
 		pitc = pitrtclk * wdt_timeout / binfo->bi_intfreq / 2;
 
-	imap->im_sit.sit_pitc = pitc << 16;
-	imap->im_sit.sit_piscr =
-	    (mk_int_int_mask(PIT_INTERRUPT) << 8) | PISCR_PIE | PISCR_PTE;
+	out_be32(imap->im_sit.sit_pitc, pitc << 16);
+
+	out_be16(imap->im_sit.sit_piscr, (mk_int_int_mask(PIT_INTERRUPT) << 8) | PISCR_PIE | PISCR_PTE);
 
 	if (setup_irq(PIT_INTERRUPT, &m8xx_wdt_irqaction))
 		panic("m8xx_wdt: error setting up the watchdog irq!");
diff --git a/arch/ppc/syslib/ppc8xx_pic.c b/arch/ppc/syslib/ppc8xx_pic.c
index d3b01c6c97d..3e6f51a61d4 100644
--- a/arch/ppc/syslib/ppc8xx_pic.c
+++ b/arch/ppc/syslib/ppc8xx_pic.c
@@ -6,6 +6,7 @@
 #include <linux/signal.h>
 #include <linux/interrupt.h>
 #include <asm/irq.h>
+#include <asm/io.h>
 #include <asm/8xx_immap.h>
 #include <asm/mpc8xx.h>
 #include "ppc8xx_pic.h"
@@ -29,8 +30,7 @@ static void m8xx_mask_irq(unsigned int irq_nr)
 	word = irq_nr >> 5;
 
 	ppc_cached_irq_mask[word] &= ~(1 << (31-bit));
-	((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
-						ppc_cached_irq_mask[word];
+	out_be32(&((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask, ppc_cached_irq_mask[word]);
 }
 
 static void m8xx_unmask_irq(unsigned int irq_nr)
@@ -41,8 +41,7 @@ static void m8xx_unmask_irq(unsigned int irq_nr)
 	word = irq_nr >> 5;
 
 	ppc_cached_irq_mask[word] |= (1 << (31-bit));
-	((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
-						ppc_cached_irq_mask[word];
+	out_be32(&((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask, ppc_cached_irq_mask[word]);
 }
 
 static void m8xx_end_irq(unsigned int irq_nr)
@@ -55,8 +54,7 @@ static void m8xx_end_irq(unsigned int irq_nr)
 		word = irq_nr >> 5;
 
 		ppc_cached_irq_mask[word] |= (1 << (31-bit));
-		((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
-			ppc_cached_irq_mask[word];
+		out_be32(&((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask, ppc_cached_irq_mask[word]);
 	}
 }
 
@@ -69,9 +67,8 @@ static void m8xx_mask_and_ack(unsigned int irq_nr)
 	word = irq_nr >> 5;
 
 	ppc_cached_irq_mask[word] &= ~(1 << (31-bit));
-	((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
-						ppc_cached_irq_mask[word];
-	((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sipend = 1 << (31-bit);
+	out_be32(&((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask, ppc_cached_irq_mask[word]);
+	out_be32(&((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sipend, 1 << (31-bit));
 }
 
 struct hw_interrupt_type ppc8xx_pic = {
@@ -93,7 +90,7 @@ m8xx_get_irq(struct pt_regs *regs)
 	/* For MPC8xx, read the SIVEC register and shift the bits down
 	 * to get the irq number.
 	 */
-	irq = ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sivec >> 26;
+	irq = in_be32(&((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sivec) >> 26;
 
 	/*
 	 * When we read the sivec without an interrupt to process, we will