/* *	Intel CPU Microcode Update Driver for Linux * *	Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com> *			   H Peter Anvin" <hpa@zytor.com> * *	This driver allows to upgrade microcode on Intel processors *	belonging to IA-32 family - PentiumPro, Pentium II, *	Pentium III, Xeon, Pentium 4, etc. * *	Reference: Section 8.11 of Volume 3a, IA-32 Intel? Architecture *	Software Developer's Manual *	Order Number 253668 or free download from: * *	http://developer.intel.com/Assets/PDF/manual/253668.pdf * *	For more information, go to http://www.urbanmyth.org/microcode * *	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. * */#include <linux/firmware.h>#include <linux/uaccess.h>#include <linux/kernel.h>#include <linux/module.h> #include <asm/microcode_intel.h>#include <asm/processor.h>#include <asm/msr.h> static inline intupdate_match_cpu(unsigned int csig, unsigned int cpf,		 unsigned int sig, unsigned int pf){	return (!sigmatch(sig, csig, pf, cpf)) ? 0 : 1;} intupdate_match_revision(struct microcode_header_intel *mc_header, int rev){	return (mc_header->rev <= rev) ? 0 : 1;} int microcode_sanity_check(void *mc, int print_err){	unsigned long total_size, data_size, ext_table_size;	struct microcode_header_intel *mc_header = mc;	struct extended_sigtable *ext_header = NULL;	int sum, orig_sum, ext_sigcount = 0, i;	struct extended_signature *ext_sig; 	total_size = get_totalsize(mc_header);	data_size = get_datasize(mc_header); 	if (data_size + MC_HEADER_SIZE > total_size) {		if (print_err)			pr_err("error! Bad data size in microcode data file\n");		return -EINVAL;	} 	if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {		if (print_err)			pr_err("error! Unknown microcode update format\n");		return -EINVAL;	}	ext_table_size = total_size - (MC_HEADER_SIZE + data_size);	if (ext_table_size) {		if ((ext_table_size < EXT_HEADER_SIZE)		 || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {			if (print_err)				pr_err("error! Small exttable size in microcode data file\n");			return -EINVAL;		}		ext_header = mc + MC_HEADER_SIZE + data_size;		if (ext_table_size != exttable_size(ext_header)) {			if (print_err)				pr_err("error! Bad exttable size in microcode data file\n");			return -EFAULT;		}		ext_sigcount = ext_header->count;	} 	/* check extended table checksum */	if (ext_table_size) {		int ext_table_sum = 0;		int *ext_tablep = (int *)ext_header; 		i = ext_table_size / DWSIZE;		while (i--)			ext_table_sum += ext_tablep[i];		if (ext_table_sum) {			if (print_err)				pr_warn("aborting, bad extended signature table checksum\n");			return -EINVAL;		}	} 	/* calculate the checksum */	orig_sum = 0;	i = (MC_HEADER_SIZE + data_size) / DWSIZE;	while (i--)		orig_sum += ((int *)mc)[i];	if (orig_sum) {		if (print_err)			pr_err("aborting, bad checksum\n");		return -EINVAL;	}	if (!ext_table_size)		return 0;	/* check extended signature checksum */	for (i = 0; i < ext_sigcount; i++) {		ext_sig = (void *)ext_header + EXT_HEADER_SIZE +			  EXT_SIGNATURE_SIZE * i;		sum = orig_sum			- (mc_header->sig + mc_header->pf + mc_header->cksum)			+ (ext_sig->sig + ext_sig->pf + ext_sig->cksum);		if (sum) {			if (print_err)				pr_err("aborting, bad checksum\n");			return -EINVAL;		}	}	return 0;}EXPORT_SYMBOL_GPL(microcode_sanity_check); /* * return 0 - no update found * return 1 - found update */int get_matching_sig(unsigned int csig, int cpf, void *mc, int rev){	struct microcode_header_intel *mc_header = mc;	struct extended_sigtable *ext_header;	unsigned long total_size = get_totalsize(mc_header);	int ext_sigcount, i;	struct extended_signature *ext_sig; 	if (update_match_cpu(csig, cpf, mc_header->sig, mc_header->pf))		return 1; 	/* Look for ext. headers: */	if (total_size <= get_datasize(mc_header) + MC_HEADER_SIZE)		return 0; 	ext_header = mc + get_datasize(mc_header) + MC_HEADER_SIZE;	ext_sigcount = ext_header->count;	ext_sig = (void *)ext_header + EXT_HEADER_SIZE; 	for (i = 0; i < ext_sigcount; i++) {		if (update_match_cpu(csig, cpf, ext_sig->sig, ext_sig->pf))			return 1;		ext_sig++;	}	return 0;} /* * return 0 - no update found * return 1 - found update */int get_matching_microcode(unsigned int csig, int cpf, void *mc, int rev){	struct microcode_header_intel *mc_header = mc; 	if (!update_match_revision(mc_header, rev))		return 0; 	return get_matching_sig(csig, cpf, mc, rev);}EXPORT_SYMBOL_GPL(get_matching_microcode);