Function diff_msr

util/msrtool/msrutils.c:303–342

* Compare two MSR values and print any differences with field definitions and * both old and new values decoded. * * @param f Output stream. * @param addr MSR address. * @param a Left value. * @param b Right value. * @return 1 when a and b differ, 0 when they are equal or only reserved bits * differ and processing of reserved bits was not requested (with -r). */

 * differ and processing of reserved bits was not requested (with -r).
 */
uint8_t diff_msr(FILE *f, const uint32_t addr, const struct msr a, const struct msr b) {
	uint8_t ret = 0, first = 1;
	struct msr aval, bval, mask;
	const struct msrdef *m = findmsrdef(addr);
	const struct msrbits *mb;

	if (a.hi == b.hi && a.lo == b.lo)
		return 0;

	if (NULL == m) {
		fprintf(stderr, "MSR 0x%08x has no definition! Please add it and send a Signed-off-by patch\n", addr);
		fprintf(stderr, "to coreboot@coreboot.org. Thank you for your help!\n");
		return 1;
	}

	for (mb = m->bits; mb->size; mb++) {
		if (!reserved && 0 == strcmp(mb->name, "RSVD"))
			continue;
		mask.hi = mask.lo = 0xffffffff;
		mask = msr_shr(mask, 64 - mb->size);
		aval = msr_shr(a, mb->start - mb->size + 1);
		bval = msr_shr(b, mb->start - mb->size + 1);
		msr_and(&aval, mask);
		msr_and(&bval, mask);
		if (msr_eq(aval, bval))
			continue;
		if (first) {
			fprintf(f, "# %s\n", m->symbol);
			fprintf(f, "-0x%08x 0x%08x%08x\n", addr, a.hi, a.lo);
			fprintf(f, "+0x%08x 0x%08x%08x\n", addr, b.hi, b.lo);
			first = 0;
			ret = 1;
		}
		print_bitdef(f, mb, "\n-");
		print_bitval(f, mb, aval);
		fprintf(f, "+");
		print_bitval(f, mb, bval);
	}
	return ret;
}