[PARISC] Kill off broken irqstack code

It's been unfinished and broken long enough, and I have some ideas on how
to do it more cleanly.

Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>

6 files changed, 3 insertions, 67 deletions

diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S
index f324939bb9af..111d47284eac 100644
--- a/arch/parisc/kernel/entry.S
+++ b/arch/parisc/kernel/entry.S
@@ -98,7 +98,6 @@
          * The "get_stack" macros are responsible for determining the
          * kernel stack value.
          *
-         * For Faults:
          *      If sr7 == 0
          *          Already using a kernel stack, so call the
          *          get_stack_use_r30 macro to push a pt_regs structure
@@ -110,26 +109,6 @@
          *          task pointer pointed to by cr30. Set the stack
          *          pointer to point to the end of the task structure.
          *
-         * For Interrupts:
-         *      If sr7 == 0
-         *          Already using a kernel stack, check to see if r30
-         *          is already pointing to the per processor interrupt
-         *          stack. If it is, call the get_stack_use_r30 macro
-         *          to push a pt_regs structure on the stack, and store
-         *          registers there. Otherwise, call get_stack_use_cr31
-         *          to get a pointer to the base of the interrupt stack
-         *          and push a pt_regs structure on that stack.
-         *      else
-         *          Need to set up a kernel stack, so call the
-         *          get_stack_use_cr30 macro to set up a pointer
-         *          to the pt_regs structure contained within the
-         *          task pointer pointed to by cr30. Set the stack
-         *          pointer to point to the end of the task structure.
-         *          N.B: We don't use the interrupt stack for the
-         *          first interrupt from userland, because signals/
-         *          resched's are processed when returning to userland,
-         *          and we can sleep in those cases.
-         *
          * Note that we use shadowed registers for temps until
          * we can save %r26 and %r29. %r26 is used to preserve
          * %r8 (a shadowed register) which temporarily contained
@@ -1086,23 +1065,13 @@ intr_do_preempt:
 
 intr_extint:
         CMPIB=,n 0,%r16,1f
+
         get_stack_use_cr30
-        b,n 3f
+        b,n 2f
 
 1:
-#if 0  /* Interrupt Stack support not working yet! */
-        mfctl   %cr31,%r1
-        copy    %r30,%r17
-        /* FIXME! depi below has hardcoded idea of interrupt stack size (32k)*/
-        DEPI    0,31,15,%r17
-        CMPB=,n %r1,%r17,2f
-        get_stack_use_cr31
-        b,n 3f
-#endif
-2:
         get_stack_use_r30
-
-3:
+2:
         save_specials   %r29
         virt_map
         save_general    %r29
diff --git a/arch/parisc/kernel/head.S b/arch/parisc/kernel/head.S
index 369919d828fb..a7b8859488bb 100644
--- a/arch/parisc/kernel/head.S
+++ b/arch/parisc/kernel/head.S
@@ -128,10 +128,6 @@ $pgt_fill_loop:
         /* And the stack pointer too */
         ldo             THREAD_SZ_ALGN(%r6),%sp
 
-        /* And the interrupt stack */
-        load32          interrupt_stack,%r6
-        mtctl           %r6,%cr31
-
 #ifdef CONFIG_SMP
         /* Set the smp rendevous address into page zero.
         ** It would be safer to do this in init_smp_config() but
diff --git a/arch/parisc/kernel/init_task.c b/arch/parisc/kernel/init_task.c
index 3b2f7d395bde..26198a074d67 100644
--- a/arch/parisc/kernel/init_task.c
+++ b/arch/parisc/kernel/init_task.c
@@ -49,7 +49,6 @@ EXPORT_SYMBOL(init_mm);
  * way process stacks are handled. This is done by having a special
  * "init_task" linker map entry..
  */
-unsigned char interrupt_stack[ISTACK_SIZE] __attribute__ ((section("init_istack"), aligned(PAGE_SIZE)));
 union thread_union init_thread_union
         __attribute__((aligned(128))) __attribute__((__section__(".data.init_task"))) =
                 { INIT_THREAD_INFO(init_task) };
diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c
index d7bc7bb42c94..85fc7754ec25 100644
--- a/arch/parisc/kernel/smp.c
+++ b/arch/parisc/kernel/smp.c
@@ -432,22 +432,10 @@ smp_cpu_init(int cpunum)
 void __init smp_callin(void)
 {
         int slave_id = cpu_now_booting;
-#if 0
-        void *istack;
-#endif
 
         smp_cpu_init(slave_id);
         preempt_disable();
 
-#if 0   /* NOT WORKING YET - see entry.S */
-        istack = (void *)__get_free_pages(GFP_KERNEL,ISTACK_ORDER);
-        if (istack == NULL) {
-            printk(KERN_CRIT "Failed to allocate interrupt stack for cpu %d\n",slave_id);
-            BUG();
-        }
-        mtctl(istack,31);
-#endif
-
         flush_cache_all_local(); /* start with known state */
         flush_tlb_all_local(NULL);
 
diff --git a/arch/parisc/kernel/vmlinux.lds.S b/arch/parisc/kernel/vmlinux.lds.S
index d6dbcbcdcc2e..40d0ff9b81ab 100644
--- a/arch/parisc/kernel/vmlinux.lds.S
+++ b/arch/parisc/kernel/vmlinux.lds.S
@@ -153,14 +153,6 @@ SECTIONS
                 *(.data.init_task)
         }
 
-        /* The interrupt stack is currently partially coded, but not yet
-         * implemented
-         */
-        . = ALIGN(16384);       
-        init_istack : {
-                *(init_istack)
-        }
-
 #ifdef CONFIG_64BIT
         . = ALIGN(16);
         /* Linkage tables */
diff --git a/include/asm-parisc/pgtable.h b/include/asm-parisc/pgtable.h
index 33ed0e73227b..b5a8797dcc5c 100644
--- a/include/asm-parisc/pgtable.h
+++ b/include/asm-parisc/pgtable.h
@@ -49,14 +49,6 @@
 #define pgd_ERROR(e) \
         printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))
 
- /* Note: If you change ISTACK_SIZE, you need to change the corresponding
-  * values in vmlinux.lds and vmlinux64.lds (init_istack section). Also,
-  * the "order" and size need to agree.
-  */
-
-#define  ISTACK_SIZE  32768 /* Interrupt Stack Size */
-#define  ISTACK_ORDER 3
-
 /* This is the size of the initially mapped kernel memory */
 #ifdef CONFIG_64BIT
 #define KERNEL_INITIAL_ORDER    24      /* 0 to 1<<24 = 16MB */