simplify interrupt handling

We have removed spl levels, now remove the machinery to manage different
PIC masks according to levels. Only keep machinery to disable interrupts
whatever the level.

* i386/i386/pic.c (pic_mask): Remove array.
(picinit): Do not form PIC mask. Set initial PIC mask to 0.
(form_pic_mask): Remove function.
* i386/i386/pic.h (form_pic_mask, pic_mask): Remove declarations.
* i386/i386/spl.S (SETMASK): Remove macro.
(XEN_SETMASK): Add macro, containing the Xen version of SETMASK.
(spl0, splx_cli, spl) [MACH_XEN]: Call XEN_SETMASK instead of SETMASK.
* i386/i386/pit.c (clkstart): Do not call form_pic_mask.
* i386/i386at/autoconf.c (take_dev_irq, take_ctlr_irq): Likewise.
* i386/i386at/kd_mouse.c (kd_mouse_open, kd_mouse_close): Likewise.
* linux/dev/arch/i386/kernel/irq.c (mask_irq, unmask_irq): Directly update
curr_pic_mask without using pic_mask array.
(init_IRQ, restore_IRQ): do not call form_pic_mask.
* linux/dev/include/asm-i386/system.h: Include <i386/ipl.h>.
(__save_flags, __restore_flags): Use curr_ipl and splx instead of
hardware flags.
* linux/dev/init/main.c (linux_init): Do not call cli.
* linux/dev/kernel/sched.c (linux_timer_intr): Do not use pic_mask.
* linux/src/drivers/block/ide.c (try_to_identify): Disable irq probing.
* linux/src/drivers/scsi/NCR53c406a.c (NCR53c406a_detect): Disable irq
probing.

6 files changed, 18 insertions, 23 deletions

diff --git a/linux/dev/arch/i386/kernel/irq.c b/linux/dev/arch/i386/kernel/irq.c
index a02e9582..596dae6b 100644
--- a/linux/dev/arch/i386/kernel/irq.c
+++ b/linux/dev/arch/i386/kernel/irq.c
@@ -128,18 +128,15 @@ linux_intr (int irq)
 static inline void
 mask_irq (unsigned int irq_nr)
 {
-  int i;
-
-  for (i = 0; i < intpri[irq_nr]; i++)
-    pic_mask[i] |= 1 << irq_nr;
+  int new_pic_mask = curr_pic_mask | 1 << irq_nr;
 
-  if (curr_pic_mask != pic_mask[curr_ipl])
+  if (curr_pic_mask != new_pic_mask)
     {
-      curr_pic_mask = pic_mask[curr_ipl];
+      curr_pic_mask = new_pic_mask;
       if (irq_nr < 8)
-	outb (curr_pic_mask & 0xff, PIC_MASTER_OCW);
+       outb (curr_pic_mask & 0xff, PIC_MASTER_OCW);
       else
-	outb (curr_pic_mask >> 8, PIC_SLAVE_OCW);
+       outb (curr_pic_mask >> 8, PIC_SLAVE_OCW);
     }
 }
 
@@ -149,18 +146,18 @@ mask_irq (unsigned int irq_nr)
 static inline void
 unmask_irq (unsigned int irq_nr)
 {
-  int mask, i;
+  int mask;
+  int new_pic_mask;
 
   mask = 1 << irq_nr;
   if (irq_nr >= 8)
     mask |= 1 << 2;
 
-  for (i = 0; i < intpri[irq_nr]; i++)
-    pic_mask[i] &= ~mask;
+  new_pic_mask = curr_pic_mask & ~mask;
 
-  if (curr_pic_mask != pic_mask[curr_ipl])
+  if (curr_pic_mask != new_pic_mask)
     {
-      curr_pic_mask = pic_mask[curr_ipl];
+      curr_pic_mask = new_pic_mask;
       if (irq_nr < 8)
 	outb (curr_pic_mask & 0xff, PIC_MASTER_OCW);
       else
@@ -737,8 +734,6 @@ init_IRQ (void)
 	}
     }
   
-  form_pic_mask ();
-  
   /*
    * Enable interrupts.
    */
@@ -777,6 +772,5 @@ restore_IRQ (void)
    */
   ivect[0] = old_clock_handler;
   intpri[0] = old_clock_pri;
-  form_pic_mask ();
 }
   
diff --git a/linux/dev/include/asm-i386/system.h b/linux/dev/include/asm-i386/system.h
index f26a33e7..41eb65a4 100644
--- a/linux/dev/include/asm-i386/system.h
+++ b/linux/dev/include/asm-i386/system.h
@@ -1,6 +1,8 @@
 #ifndef __ASM_SYSTEM_H
 #define __ASM_SYSTEM_H
 
+#include <i386/ipl.h> /* curr_ipl, splx */
+
 #include <asm/segment.h>
 
 /*
@@ -223,10 +225,8 @@ static inline unsigned long __xchg(unsigned long x, void * ptr, int size)
 #define mb()  __asm__ __volatile__ (""   : : :"memory")
 #define __sti() __asm__ __volatile__ ("sti": : :"memory")
 #define __cli() __asm__ __volatile__ ("cli": : :"memory")
-#define __save_flags(x) \
-__asm__ __volatile__("pushf ; pop %0" : "=r" (x): /* no input */ :"memory")
-#define __restore_flags(x) \
-__asm__ __volatile__("push %0 ; popf": /* no output */ :"g" (x):"memory")
+#define __save_flags(x) (x = ((curr_ipl > 0) ? 0 : (1 << 9)))
+#define __restore_flags(x) splx((x & (1 << 9)) ? 0 : 7)
 
 #ifdef __SMP__
 
diff --git a/linux/dev/init/main.c b/linux/dev/init/main.c
index 3740c12c..6d853957 100644
--- a/linux/dev/init/main.c
+++ b/linux/dev/init/main.c
@@ -151,7 +151,6 @@ linux_init (void)
   linux_net_emulation_init ();
 #endif
 
-  cli ();
   device_setup ();
 
 #ifdef CONFIG_PCMCIA
diff --git a/linux/dev/kernel/sched.c b/linux/dev/kernel/sched.c
index 87906a45..2a9eeb3f 100644
--- a/linux/dev/kernel/sched.c
+++ b/linux/dev/kernel/sched.c
@@ -622,6 +622,6 @@ linux_timer_intr (void)
     mark_bh (TQUEUE_BH);
 #if 0
   if (linux_timer_print)
-    printf ("linux_timer_intr: pic_mask[0] %x\n", pic_mask[0]);
+    printf ("linux_timer_intr: hello\n");
 #endif
 }
diff --git a/linux/src/drivers/block/ide.c b/linux/src/drivers/block/ide.c
index 43b12f1f..170e4e13 100644
--- a/linux/src/drivers/block/ide.c
+++ b/linux/src/drivers/block/ide.c
@@ -2703,6 +2703,8 @@ static int try_to_identify (ide_drive_t *drive, byte cmd)
 	int irq_off;
 
 	if (!HWIF(drive)->irq) {		/* already got an IRQ? */
+		printk("%s: Not probing legacy IRQs)\n", drive->name);
+		return 2;
 		probe_irq_off(probe_irq_on());	/* clear dangling irqs */
 		irqs_on = probe_irq_on();	/* start monitoring irqs */
 		OUT_BYTE(drive->ctl,IDE_CONTROL_REG);	/* enable device irq */
diff --git a/linux/src/drivers/scsi/NCR53c406a.c b/linux/src/drivers/scsi/NCR53c406a.c
index 9f2de9a0..7745f5ad 100644
--- a/linux/src/drivers/scsi/NCR53c406a.c
+++ b/linux/src/drivers/scsi/NCR53c406a.c
@@ -525,7 +525,7 @@ NCR53c406a_detect(Scsi_Host_Template * tpnt){
     
 #ifndef IRQ_LEV
     if (irq_level < 0) {		/* LILO override if >= 0*/
-        irq_level=irq_probe();
+        irq_level = -1; // XXX No probing irq_probe();
         if (irq_level < 0) {		/* Trouble */
             printk("NCR53c406a: IRQ problem, irq_level=%d, giving up\n", irq_level);
             return 0;