Author: mcayland Date: Sun Jun 21 20:52:38 2015 New Revision: 1342 URL: http://tracker.coreboot.org/trac/openbios/changeset/1342
Log: ppc: add Adler-32 checksum capability
This patch provides an implementation of the adler32 Forth word as required by Mac OS 9 and BootX.
Signed-off-by: Cormac O'Brien i.am.cormac.obrien@gmail.com Signed-off-by: Mark Cave-Ayland mark.cave-ayland@ilande.co.uk
Modified: trunk/openbios-devel/arch/ppc/qemu/init.c
Modified: trunk/openbios-devel/arch/ppc/qemu/init.c ============================================================================== --- trunk/openbios-devel/arch/ppc/qemu/init.c Sun Jun 21 20:52:35 2015 (r1341) +++ trunk/openbios-devel/arch/ppc/qemu/init.c Sun Jun 21 20:52:38 2015 (r1342) @@ -680,6 +680,60 @@ } }
+/* + * adler32 ( adler buf len -- checksum ) + * + * Adapted from Mark Adler's original implementation (zlib license) + * + * Both OS 9 and BootX require this word for payload validation. + */ + +#define DO1(buf,i) {s1 += buf[i]; s2 += s1;} +#define DO2(buf,i) DO1(buf,i); DO1(buf,i+1); +#define DO4(buf,i) DO2(buf,i); DO2(buf,i+2); +#define DO8(buf,i) DO4(buf,i); DO4(buf,i+4); +#define DO16(buf) DO8(buf,0); DO8(buf,8); + +static void adler32(void) +{ + uint32_t len = (uint32_t)POP(); + char *buf = (char *)POP(); + uint32_t adler = (uint32_t)POP(); + + if (buf == NULL) { + RET(-1); + } + + uint32_t base = 65521; + uint32_t nmax = 5552; + + uint32_t s1 = adler & 0xffff; + uint32_t s2 = (adler >> 16) & 0xffff; + + uint32_t k; + while (len > 0) { + k = (len < nmax ? len : nmax); + len -= k; + + while (k >= 16) { + DO16(buf); + buf += 16; + k -= 16; + } + if (k != 0) { + do { + s1 += *buf++; + s2 += s1; + } while (--k); + } + + s1 %= base; + s2 %= base; + } + + RET(s2 << 16 | s1); +} + void arch_of_init(void) { @@ -945,6 +999,9 @@
/* Implementation of filll word (required by BootX) */ bind_func("filll", ffilll); + + /* Implementation of adler32 word (required by OS 9, BootX) */ + bind_func("adler32", adler32);
bind_func("platform-boot", boot); bind_func("(go)", go);