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authorBen Dooks <ben-linux@fluff.org>2008-08-08 21:10:12 +0100
committerBen Dooks <ben-linux@fluff.org>2008-08-08 21:10:12 +0100
commitaf7a535688a758d15f06a98833e6a143b29af9de (patch)
treebac5ab210bbbbe276f0e44ed84194d7c8bb16aae /arch/arm/mach-s3c2410/include/mach/entry-macro.S
parent0c17e4ceedd35c78b1c7413dbd16279a350be6bc (diff)
parentc41107c2d4fd31924533f4dbc4c3428acc2b5894 (diff)
Merge http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm into for-rmk
Diffstat (limited to 'arch/arm/mach-s3c2410/include/mach/entry-macro.S')
-rw-r--r--arch/arm/mach-s3c2410/include/mach/entry-macro.S78
1 files changed, 78 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c2410/include/mach/entry-macro.S b/arch/arm/mach-s3c2410/include/mach/entry-macro.S
new file mode 100644
index 00000000000..473b3cd37d9
--- /dev/null
+++ b/arch/arm/mach-s3c2410/include/mach/entry-macro.S
@@ -0,0 +1,78 @@
+/*
+ * arch/arm/mach-s3c2410/include/mach/entry-macro.S
+ *
+ * Low-level IRQ helper macros for S3C2410-based platforms
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+*/
+
+/* We have a problem that the INTOFFSET register does not always
+ * show one interrupt. Occasionally we get two interrupts through
+ * the prioritiser, and this causes the INTOFFSET register to show
+ * what looks like the logical-or of the two interrupt numbers.
+ *
+ * Thanks to Klaus, Shannon, et al for helping to debug this problem
+*/
+
+#define INTPND (0x10)
+#define INTOFFSET (0x14)
+
+#include <mach/hardware.h>
+#include <asm/irq.h>
+
+ .macro get_irqnr_preamble, base, tmp
+ .endm
+
+ .macro arch_ret_to_user, tmp1, tmp2
+ .endm
+
+ .macro get_irqnr_and_base, irqnr, irqstat, base, tmp
+
+ mov \base, #S3C24XX_VA_IRQ
+
+ @@ try the interrupt offset register, since it is there
+
+ ldr \irqstat, [ \base, #INTPND ]
+ teq \irqstat, #0
+ beq 1002f
+ ldr \irqnr, [ \base, #INTOFFSET ]
+ mov \tmp, #1
+ tst \irqstat, \tmp, lsl \irqnr
+ bne 1001f
+
+ @@ the number specified is not a valid irq, so try
+ @@ and work it out for ourselves
+
+ mov \irqnr, #0 @@ start here
+
+ @@ work out which irq (if any) we got
+
+ movs \tmp, \irqstat, lsl#16
+ addeq \irqnr, \irqnr, #16
+ moveq \irqstat, \irqstat, lsr#16
+ tst \irqstat, #0xff
+ addeq \irqnr, \irqnr, #8
+ moveq \irqstat, \irqstat, lsr#8
+ tst \irqstat, #0xf
+ addeq \irqnr, \irqnr, #4
+ moveq \irqstat, \irqstat, lsr#4
+ tst \irqstat, #0x3
+ addeq \irqnr, \irqnr, #2
+ moveq \irqstat, \irqstat, lsr#2
+ tst \irqstat, #0x1
+ addeq \irqnr, \irqnr, #1
+
+ @@ we have the value
+1001:
+ adds \irqnr, \irqnr, #IRQ_EINT0
+1002:
+ @@ exit here, Z flag unset if IRQ
+
+ .endm
+
+ /* currently don't need an disable_fiq macro */
+
+ .macro disable_fiq
+ .endm