powerpc: Merge enough to start building in arch/powerpc.

This creates the directory structure under arch/powerpc and a bunch
of Kconfig files.  It does a first-cut merge of arch/powerpc/mm,
arch/powerpc/lib and arch/powerpc/platforms/powermac.  This is enough
to build a 32-bit powermac kernel with ARCH=powerpc.

For now we are getting some unmerged files from arch/ppc/kernel and
arch/ppc/syslib, or arch/ppc64/kernel.  This makes some minor changes
to files in those directories and files outside arch/powerpc.

The boot directory is still not merged.  That's going to be interesting.

Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 229 insertions, 0 deletions

diff --git a/arch/powerpc/lib/checksum64.S b/arch/powerpc/lib/checksum64.S
new file mode 100644
index 000000000000..ef96c6c58efc
--- /dev/null
+++ b/arch/powerpc/lib/checksum64.S
@@ -0,0 +1,229 @@
+/*
+ * This file contains assembly-language implementations
+ * of IP-style 1's complement checksum routines.
+ *      
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ *
+ * Severely hacked about by Paul Mackerras (paulus@cs.anu.edu.au).
+ */
+
+#include <linux/sys.h>
+#include <asm/processor.h>
+#include <asm/errno.h>
+#include <asm/ppc_asm.h>
+
+/*
+ * ip_fast_csum(r3=buf, r4=len) -- Optimized for IP header
+ * len is in words and is always >= 5.
+ *
+ * In practice len == 5, but this is not guaranteed.  So this code does not
+ * attempt to use doubleword instructions.
+ */
+_GLOBAL(ip_fast_csum)
+        lwz     r0,0(r3)
+        lwzu    r5,4(r3)
+        addic.  r4,r4,-2
+        addc    r0,r0,r5
+        mtctr   r4
+        blelr-
+1:      lwzu    r4,4(r3)
+        adde    r0,r0,r4
+        bdnz    1b
+        addze   r0,r0           /* add in final carry */
+        rldicl  r4,r0,32,0      /* fold two 32-bit halves together */
+        add     r0,r0,r4
+        srdi    r0,r0,32
+        rlwinm  r3,r0,16,0,31   /* fold two halves together */
+        add     r3,r0,r3
+        not     r3,r3
+        srwi    r3,r3,16
+        blr
+
+/*
+ * Compute checksum of TCP or UDP pseudo-header:
+ *   csum_tcpudp_magic(r3=saddr, r4=daddr, r5=len, r6=proto, r7=sum)
+ * No real gain trying to do this specially for 64 bit, but
+ * the 32 bit addition may spill into the upper bits of
+ * the doubleword so we still must fold it down from 64.
+ */     
+_GLOBAL(csum_tcpudp_magic)
+        rlwimi  r5,r6,16,0,15   /* put proto in upper half of len */
+        addc    r0,r3,r4        /* add 4 32-bit words together */
+        adde    r0,r0,r5
+        adde    r0,r0,r7
+        rldicl  r4,r0,32,0      /* fold 64 bit value */
+        add     r0,r4,r0
+        srdi    r0,r0,32
+        rlwinm  r3,r0,16,0,31   /* fold two halves together */
+        add     r3,r0,r3
+        not     r3,r3
+        srwi    r3,r3,16
+        blr
+
+/*
+ * Computes the checksum of a memory block at buff, length len,
+ * and adds in "sum" (32-bit).
+ *
+ * This code assumes at least halfword alignment, though the length
+ * can be any number of bytes.  The sum is accumulated in r5.
+ *
+ * csum_partial(r3=buff, r4=len, r5=sum)
+ */
+_GLOBAL(csum_partial)
+        subi    r3,r3,8         /* we'll offset by 8 for the loads */
+        srdi.   r6,r4,3         /* divide by 8 for doubleword count */
+        addic   r5,r5,0         /* clear carry */
+        beq     3f              /* if we're doing < 8 bytes */
+        andi.   r0,r3,2         /* aligned on a word boundary already? */
+        beq+    1f
+        lhz     r6,8(r3)        /* do 2 bytes to get aligned */
+        addi    r3,r3,2
+        subi    r4,r4,2
+        addc    r5,r5,r6
+        srdi.   r6,r4,3         /* recompute number of doublewords */
+        beq     3f              /* any left? */
+1:      mtctr   r6
+2:      ldu     r6,8(r3)        /* main sum loop */
+        adde    r5,r5,r6
+        bdnz    2b
+        andi.   r4,r4,7         /* compute bytes left to sum after doublewords */
+3:      cmpwi   0,r4,4          /* is at least a full word left? */
+        blt     4f
+        lwz     r6,8(r3)        /* sum this word */
+        addi    r3,r3,4
+        subi    r4,r4,4
+        adde    r5,r5,r6
+4:      cmpwi   0,r4,2          /* is at least a halfword left? */
+        blt+    5f
+        lhz     r6,8(r3)        /* sum this halfword */
+        addi    r3,r3,2
+        subi    r4,r4,2
+        adde    r5,r5,r6
+5:      cmpwi   0,r4,1          /* is at least a byte left? */
+        bne+    6f
+        lbz     r6,8(r3)        /* sum this byte */
+        slwi    r6,r6,8         /* this byte is assumed to be the upper byte of a halfword */
+        adde    r5,r5,r6
+6:      addze   r5,r5           /* add in final carry */
+        rldicl  r4,r5,32,0      /* fold two 32-bit halves together */
+        add     r3,r4,r5
+        srdi    r3,r3,32
+        blr
+
+/*
+ * Computes the checksum of a memory block at src, length len,
+ * and adds in "sum" (32-bit), while copying the block to dst.
+ * If an access exception occurs on src or dst, it stores -EFAULT
+ * to *src_err or *dst_err respectively, and (for an error on
+ * src) zeroes the rest of dst.
+ *
+ * This code needs to be reworked to take advantage of 64 bit sum+copy.
+ * However, due to tokenring halfword alignment problems this will be very
+ * tricky.  For now we'll leave it until we instrument it somehow.
+ *
+ * csum_partial_copy_generic(r3=src, r4=dst, r5=len, r6=sum, r7=src_err, r8=dst_err)
+ */
+_GLOBAL(csum_partial_copy_generic)
+        addic   r0,r6,0
+        subi    r3,r3,4
+        subi    r4,r4,4
+        srwi.   r6,r5,2
+        beq     3f              /* if we're doing < 4 bytes */
+        andi.   r9,r4,2         /* Align dst to longword boundary */
+        beq+    1f
+81:     lhz     r6,4(r3)        /* do 2 bytes to get aligned */
+        addi    r3,r3,2
+        subi    r5,r5,2
+91:     sth     r6,4(r4)
+        addi    r4,r4,2
+        addc    r0,r0,r6
+        srwi.   r6,r5,2         /* # words to do */
+        beq     3f
+1:      mtctr   r6
+82:     lwzu    r6,4(r3)        /* the bdnz has zero overhead, so it should */
+92:     stwu    r6,4(r4)        /* be unnecessary to unroll this loop */
+        adde    r0,r0,r6
+        bdnz    82b
+        andi.   r5,r5,3
+3:      cmpwi   0,r5,2
+        blt+    4f
+83:     lhz     r6,4(r3)
+        addi    r3,r3,2
+        subi    r5,r5,2
+93:     sth     r6,4(r4)
+        addi    r4,r4,2
+        adde    r0,r0,r6
+4:      cmpwi   0,r5,1
+        bne+    5f
+84:     lbz     r6,4(r3)
+94:     stb     r6,4(r4)
+        slwi    r6,r6,8         /* Upper byte of word */
+        adde    r0,r0,r6
+5:      addze   r3,r0           /* add in final carry (unlikely with 64-bit regs) */
+        rldicl  r4,r3,32,0      /* fold 64 bit value */
+        add     r3,r4,r3
+        srdi    r3,r3,32
+        blr
+
+/* These shouldn't go in the fixup section, since that would
+   cause the ex_table addresses to get out of order. */
+
+        .globl src_error_1
+src_error_1:
+        li      r6,0
+        subi    r5,r5,2
+95:     sth     r6,4(r4)
+        addi    r4,r4,2
+        srwi.   r6,r5,2
+        beq     3f
+        mtctr   r6
+        .globl src_error_2
+src_error_2:
+        li      r6,0
+96:     stwu    r6,4(r4)
+        bdnz    96b
+3:      andi.   r5,r5,3
+        beq     src_error
+        .globl src_error_3
+src_error_3:
+        li      r6,0
+        mtctr   r5
+        addi    r4,r4,3
+97:     stbu    r6,1(r4)
+        bdnz    97b
+        .globl src_error
+src_error:
+        cmpdi   0,r7,0
+        beq     1f
+        li      r6,-EFAULT
+        stw     r6,0(r7)
+1:      addze   r3,r0
+        blr
+
+        .globl dst_error
+dst_error:
+        cmpdi   0,r8,0
+        beq     1f
+        li      r6,-EFAULT
+        stw     r6,0(r8)
+1:      addze   r3,r0
+        blr
+
+.section __ex_table,"a"
+        .align  3
+        .llong  81b,src_error_1
+        .llong  91b,dst_error
+        .llong  82b,src_error_2
+        .llong  92b,dst_error
+        .llong  83b,src_error_3
+        .llong  93b,dst_error
+        .llong  84b,src_error_3
+        .llong  94b,dst_error
+        .llong  95b,dst_error
+        .llong  96b,dst_error
+        .llong  97b,dst_error