* Update Intel IXP4xx support
- Add IXP4xx NPE ethernet MAC support
- Add support for Intel IXDPG425 board
- Add support for Prodrive PDNB3 board
- Add IRQ support
Patch by Stefan Roese, 23 May 2006
[This patch does not include cpu/ixp/npe/IxNpeMicrocode.c which still
sufferes from licensing issues. Blame Intel.]
diff --git a/lib_arm/_divsi3.S b/lib_arm/_divsi3.S
new file mode 100644
index 0000000..9dc15f6
--- /dev/null
+++ b/lib_arm/_divsi3.S
@@ -0,0 +1,140 @@
+
+.macro ARM_DIV_BODY dividend, divisor, result, curbit
+
+#if __LINUX_ARM_ARCH__ >= 5
+
+ clz \curbit, \divisor
+ clz \result, \dividend
+ sub \result, \curbit, \result
+ mov \curbit, #1
+ mov \divisor, \divisor, lsl \result
+ mov \curbit, \curbit, lsl \result
+ mov \result, #0
+
+#else
+
+ @ Initially shift the divisor left 3 bits if possible,
+ @ set curbit accordingly. This allows for curbit to be located
+ @ at the left end of each 4 bit nibbles in the division loop
+ @ to save one loop in most cases.
+ tst \divisor, #0xe0000000
+ moveq \divisor, \divisor, lsl #3
+ moveq \curbit, #8
+ movne \curbit, #1
+
+ @ Unless the divisor is very big, shift it up in multiples of
+ @ four bits, since this is the amount of unwinding in the main
+ @ division loop. Continue shifting until the divisor is
+ @ larger than the dividend.
+1: cmp \divisor, #0x10000000
+ cmplo \divisor, \dividend
+ movlo \divisor, \divisor, lsl #4
+ movlo \curbit, \curbit, lsl #4
+ blo 1b
+
+ @ For very big divisors, we must shift it a bit at a time, or
+ @ we will be in danger of overflowing.
+1: cmp \divisor, #0x80000000
+ cmplo \divisor, \dividend
+ movlo \divisor, \divisor, lsl #1
+ movlo \curbit, \curbit, lsl #1
+ blo 1b
+
+ mov \result, #0
+
+#endif
+
+ @ Division loop
+1: cmp \dividend, \divisor
+ subhs \dividend, \dividend, \divisor
+ orrhs \result, \result, \curbit
+ cmp \dividend, \divisor, lsr #1
+ subhs \dividend, \dividend, \divisor, lsr #1
+ orrhs \result, \result, \curbit, lsr #1
+ cmp \dividend, \divisor, lsr #2
+ subhs \dividend, \dividend, \divisor, lsr #2
+ orrhs \result, \result, \curbit, lsr #2
+ cmp \dividend, \divisor, lsr #3
+ subhs \dividend, \dividend, \divisor, lsr #3
+ orrhs \result, \result, \curbit, lsr #3
+ cmp \dividend, #0 @ Early termination?
+ movnes \curbit, \curbit, lsr #4 @ No, any more bits to do?
+ movne \divisor, \divisor, lsr #4
+ bne 1b
+
+.endm
+
+.macro ARM_DIV2_ORDER divisor, order
+
+#if __LINUX_ARM_ARCH__ >= 5
+
+ clz \order, \divisor
+ rsb \order, \order, #31
+
+#else
+
+ cmp \divisor, #(1 << 16)
+ movhs \divisor, \divisor, lsr #16
+ movhs \order, #16
+ movlo \order, #0
+
+ cmp \divisor, #(1 << 8)
+ movhs \divisor, \divisor, lsr #8
+ addhs \order, \order, #8
+
+ cmp \divisor, #(1 << 4)
+ movhs \divisor, \divisor, lsr #4
+ addhs \order, \order, #4
+
+ cmp \divisor, #(1 << 2)
+ addhi \order, \order, #3
+ addls \order, \order, \divisor, lsr #1
+
+#endif
+
+.endm
+
+ .align 5
+.globl __divsi3
+__divsi3:
+ cmp r1, #0
+ eor ip, r0, r1 @ save the sign of the result.
+ beq Ldiv0
+ rsbmi r1, r1, #0 @ loops below use unsigned.
+ subs r2, r1, #1 @ division by 1 or -1 ?
+ beq 10f
+ movs r3, r0
+ rsbmi r3, r0, #0 @ positive dividend value
+ cmp r3, r1
+ bls 11f
+ tst r1, r2 @ divisor is power of 2 ?
+ beq 12f
+
+ ARM_DIV_BODY r3, r1, r0, r2
+
+ cmp ip, #0
+ rsbmi r0, r0, #0
+ mov pc, lr
+
+10: teq ip, r0 @ same sign ?
+ rsbmi r0, r0, #0
+ mov pc, lr
+
+11: movlo r0, #0
+ moveq r0, ip, asr #31
+ orreq r0, r0, #1
+ mov pc, lr
+
+12: ARM_DIV2_ORDER r1, r2
+
+ cmp ip, #0
+ mov r0, r3, lsr r2
+ rsbmi r0, r0, #0
+ mov pc, lr
+
+Ldiv0:
+
+ str lr, [sp, #-4]!
+ bl __div0
+ mov r0, #0 @ About as wrong as it could be.
+ ldr pc, [sp], #4
