[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>

5 files changed, 23 insertions, 39 deletions

diff --git a/arch/arm/mach-iop32x/irq.c b/arch/arm/mach-iop32x/irq.c
index 76f2d561dbc1..cdd6943ce768 100644
--- a/arch/arm/mach-iop32x/irq.c
+++ b/arch/arm/mach-iop32x/irq.c
@@ -27,12 +27,16 @@ static u32 iop321_mask /* = 0 */;
 
 static inline void intctl_write(u32 val)
 {
+        iop3xx_cp6_enable();
         asm volatile("mcr p6,0,%0,c0,c0,0"::"r" (val));
+        iop3xx_cp6_disable();
 }
 
 static inline void intstr_write(u32 val)
 {
+        iop3xx_cp6_enable();
         asm volatile("mcr p6,0,%0,c4,c0,0"::"r" (val));
+        iop3xx_cp6_disable();
 }
 
 static void
@@ -61,24 +65,7 @@ struct irq_chip ext_chip = {
 
 void __init iop321_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_write(0);                // disable all interrupts
         intstr_write(0);                // treat all as IRQ
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);
diff --git a/arch/arm/plat-iop/time.c b/arch/arm/plat-iop/time.c
index 5730a0d7ed67..bed20f3669f4 100644
--- a/arch/arm/plat-iop/time.c
+++ b/arch/arm/plat-iop/time.c
@@ -51,7 +51,9 @@ iop3xx_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 {
         write_seqlock(&xtime_lock);
 
+        iop3xx_cp6_enable();
         asm volatile("mcr p6, 0, %0, c6, c1, 0" : : "r" (1));
+        iop3xx_cp6_disable();
 
         while ((signed long)(next_jiffy_time - *IOP3XX_TU_TCR1)
                                                         >= ticks_per_jiffy) {
@@ -85,10 +87,12 @@ void __init iop3xx_init_time(unsigned long tick_rate)
          * We use timer 0 for our timer interrupt, and timer 1 as
          * monotonic counter for tracking missed jiffies.
          */
+        iop3xx_cp6_enable();
         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));
+        iop3xx_cp6_disable();
 
         setup_irq(IRQ_IOP3XX_TIMER0, &iop3xx_timer_irq);
 }
diff --git a/include/asm-arm/arch-iop32x/entry-macro.S b/include/asm-arm/arch-iop32x/entry-macro.S
index 52d9435c6a34..00038c17317a 100644
--- a/include/asm-arm/arch-iop32x/entry-macro.S
+++ b/include/asm-arm/arch-iop32x/entry-macro.S
@@ -17,7 +17,8 @@
                  */
                 .macro  get_irqnr_and_base, irqnr, irqstat, base, tmp
                 mov     \irqnr, #0
-                mrc     p6, 0, \irqstat, c8, c0, 0      @ Read IINTSRC
+                ldr     \base, =IOP3XX_REG_ADDR(0x07D8)
+                ldr     \irqstat, [\base]               @ Read IINTSRC
                 cmp     \irqstat, #0
                 beq     1001f
                 clz     \irqnr, \irqstat
diff --git a/include/asm-arm/arch-iop33x/entry-macro.S b/include/asm-arm/arch-iop33x/entry-macro.S
index 980ec9b1ac83..57f6ea0069e4 100644
--- a/include/asm-arm/arch-iop33x/entry-macro.S
+++ b/include/asm-arm/arch-iop33x/entry-macro.S
@@ -17,10 +17,11 @@
                  */
                 .macro  get_irqnr_and_base, irqnr, irqstat, base, tmp
                 mov     \irqnr, #0
-                mrc     p6, 0, \irqstat, c4, c0, 0      @ Read IINTSRC0
+                ldr     \base, =IOP3XX_REG_ADDR(0x7A0)
+                ldr     \irqstat, [\base]               @ Read IINTSRC0
                 cmp     \irqstat, #0
                 bne     1002f
-                mrc     p6, 0, \irqstat, c5, c0, 0      @ Read IINTSRC1
+                ldr     \irqstat, [\base, #4]           @ Read IINTSRC1
                 cmp     \irqstat, #0
                 beq     1001f
                 clz     \irqnr, \irqstat