[ARM] 3825/1: iop3xx: use cp6 enable/disable macros

Add CP6 enable/disable sequences to the timekeeping code and the IRQ
code.  As a result, we can't depend on CP6 access being enabled when
we enter get_irqnr_and_base anymore, so switch the latter over to
using memory-mapped accesses for now.

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

1 files changed, 9 insertions, 18 deletions

diff --git a/arch/arm/mach-iop33x/irq.c b/arch/arm/mach-iop33x/irq.c
index bcffc33a5be8..d667439c8573 100644
--- a/arch/arm/mach-iop33x/irq.c
+++ b/arch/arm/mach-iop33x/irq.c
@@ -28,25 +28,33 @@ static u32 iop331_mask1 = 0;
 static inline void intctl_write0(u32 val)
 {
     // INTCTL0
+        iop3xx_cp6_enable();
         asm volatile("mcr p6,0,%0,c0,c0,0"::"r" (val));
+        iop3xx_cp6_disable();
 }
 
 static inline void intctl_write1(u32 val)
 {
     // INTCTL1
+        iop3xx_cp6_enable();
     asm volatile("mcr p6,0,%0,c1,c0,0"::"r" (val));
+        iop3xx_cp6_disable();
 }
 
 static inline void intstr_write0(u32 val)
 {
     // INTSTR0
+        iop3xx_cp6_enable();
         asm volatile("mcr p6,0,%0,c2,c0,0"::"r" (val));
+        iop3xx_cp6_disable();
 }
 
 static inline void intstr_write1(u32 val)
 {
     // INTSTR1
+        iop3xx_cp6_enable();
         asm volatile("mcr p6,0,%0,c3,c0,0"::"r" (val));
+        iop3xx_cp6_disable();
 }
 
 static void
@@ -93,24 +101,7 @@ struct irq_chip iop331_irqchip2 = {
 
 void __init iop331_init_irq(void)
 {
-        unsigned int i, tmp;
-
-        /* Enable access to coprocessor 6 for dealing with IRQs.
-         * From RMK:
-         * Basically, the Intel documentation here is poor.  It appears that
-         * you need to set the bit to be able to access the coprocessor from
-         * SVC mode.  Whether that allows access from user space or not is
-         * unclear.
-         */
-        asm volatile (
-                "mrc p15, 0, %0, c15, c1, 0\n\t"
-                "orr %0, %0, %1\n\t"
-                "mcr p15, 0, %0, c15, c1, 0\n\t"
-                /* The action is delayed, so we have to do this: */
-                "mrc p15, 0, %0, c15, c1, 0\n\t"
-                "mov %0, %0\n\t"
-                "sub pc, pc, #4"
-                : "=r" (tmp) : "i" (1 << 6) );
+        unsigned int i;
 
         intctl_write0(0);               // disable all interrupts
         intctl_write1(0);