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-rw-r--r--arch/x86/kernel/microcode_intel_lib.c174
1 files changed, 174 insertions, 0 deletions
diff --git a/arch/x86/kernel/microcode_intel_lib.c b/arch/x86/kernel/microcode_intel_lib.c
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index 0000000..ce69320
--- /dev/null
+++ b/arch/x86/kernel/microcode_intel_lib.c
@@ -0,0 +1,174 @@
+/*
+ * 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 int
+update_match_cpu(unsigned int csig, unsigned int cpf,
+ unsigned int sig, unsigned int pf)
+{
+ return (!sigmatch(sig, csig, pf, cpf)) ? 0 : 1;
+}
+
+int
+update_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);
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