patch-2.4.4 linux/arch/mips/ddb5074/int-handler.S
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- Lines: 93
- Date:
Fri Apr 13 20:26:07 2001
- Orig file:
v2.4.3/linux/arch/mips/ddb5074/int-handler.S
- Orig date:
Sat May 13 08:29:14 2000
diff -u --recursive --new-file v2.4.3/linux/arch/mips/ddb5074/int-handler.S linux/arch/mips/ddb5074/int-handler.S
@@ -7,54 +7,50 @@
*
* Copyright (C) 2000 Geert Uytterhoeven <geert@sonycom.com>
* Sony Software Development Center Europe (SDCE), Brussels
- *
- * $Id: int-handler.S,v 1.1 2000/01/26 00:07:44 ralf Exp $
*/
-
#include <asm/asm.h>
#include <asm/mipsregs.h>
#include <asm/regdef.h>
#include <asm/stackframe.h>
- /* A lot of complication here is taken away because:
- *
- * 1) We handle one interrupt and return, sitting in a loop
- * and moving across all the pending IRQ bits in the cause
- * register is _NOT_ the answer, the common case is one
- * pending IRQ so optimize in that direction.
- *
- * 2) We need not check against bits in the status register
- * IRQ mask, that would make this routine slow as hell.
- *
- * 3) Linux only thinks in terms of all IRQs on or all IRQs
- * off, nothing in between like BSD spl() brain-damage.
- *
- * Furthermore, the IRQs on the INDY look basically (barring
- * software IRQs which we don't use at all) like:
- *
- * MIPS IRQ Source
- * -------- ------
- * 0 Software (ignored)
- * 1 Software (ignored)
- * 2 Local IRQ level zero
- * 3 Local IRQ level one
- * 4 8254 Timer zero
- * 5 8254 Timer one
- * 6 Bus Error
- * 7 R4k timer (what we use)
- *
- * We handle the IRQ according to _our_ priority which is:
- *
- * Highest ---- R4k Timer
- * Local IRQ zero
- * Local IRQ one
- * Bus Error
- * 8254 Timer zero
- * Lowest ---- 8254 Timer one
- *
- * then we just return, if multiple IRQs are pending then
- * we will just take another exception, big deal.
- */
+/* A lot of complication here is taken away because:
+ *
+ * 1) We handle one interrupt and return, sitting in a loop and moving across
+ * all the pending IRQ bits in the cause register is _NOT_ the answer, the
+ * common case is one pending IRQ so optimize in that direction.
+ *
+ * 2) We need not check against bits in the status register IRQ mask, that
+ * would make this routine slow as hell.
+ *
+ * 3) Linux only thinks in terms of all IRQs on or all IRQs off, nothing in
+ * between like BSD spl() brain-damage.
+ *
+ * Furthermore, the IRQs on the INDY look basically (barring software IRQs
+ * which we don't use at all) like:
+ *
+ * MIPS IRQ Source
+ * -------- ------
+ * 0 Software (ignored)
+ * 1 Software (ignored)
+ * 2 Local IRQ level zero
+ * 3 Local IRQ level one
+ * 4 8254 Timer zero
+ * 5 8254 Timer one
+ * 6 Bus Error
+ * 7 R4k timer (what we use)
+ *
+ * We handle the IRQ according to _our_ priority which is:
+ *
+ * Highest ---- R4k Timer
+ * Local IRQ zero
+ * Local IRQ one
+ * Bus Error
+ * 8254 Timer zero
+ * Lowest ---- 8254 Timer one
+ *
+ * then we just return, if multiple IRQs are pending then we will just take
+ * another exception, big deal.
+ */
.text
.set noreorder
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