Merge tag 'for-v4.6-rc/omap-fixes-a' of git://git.kernel.org/pub/scm/linux/kernel/git/pjw/omap-pending into omap-for-v4.6/fixes

ARM: OMAP2+: first hwmod fix for v4.6-rc

Fix a longstanding bug in the hwmod code that could cause
hardware SYSCONFIG register values to not match the kernel's
idea of what they should be, and that could result in lower
performance during IP block idle entry.

Basic build, boot, and PM test logs are available here:

http://www.pwsan.com/omap/testlogs/omap-hwmod-fixes-a-for-v4.6-rc/20160326231727/

1 files changed, 37 insertions, 21 deletions

diff --git a/arch/x86/kernel/cpu/microcode/intel_lib.c b/arch/x86/kernel/cpu/microcode/intel_lib.c
index b96896bcbdaf..2ce1a7dc45b7 100644
--- a/arch/x86/kernel/cpu/microcode/intel_lib.c
+++ b/arch/x86/kernel/cpu/microcode/intel_lib.c
@@ -49,7 +49,7 @@ 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;
+	u32 sum, orig_sum, ext_sigcount = 0, i;
 	struct extended_signature *ext_sig;
 
 	total_size = get_totalsize(mc_header);
@@ -57,69 +57,85 @@ int microcode_sanity_check(void *mc, int print_err)
 
 	if (data_size + MC_HEADER_SIZE > total_size) {
 		if (print_err)
-			pr_err("error! Bad data size in microcode data file\n");
+			pr_err("Error: bad microcode data file size.\n");
 		return -EINVAL;
 	}
 
 	if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {
 		if (print_err)
-			pr_err("error! Unknown microcode update format\n");
+			pr_err("Error: invalid/unknown microcode update format.\n");
 		return -EINVAL;
 	}
+
 	ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
 	if (ext_table_size) {
+		u32 ext_table_sum = 0;
+		u32 *ext_tablep;
+
 		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");
+				pr_err("Error: truncated extended signature table.\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");
+				pr_err("Error: extended signature table size mismatch.\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;
+		/*
+		 * Check extended table checksum: the sum of all dwords that
+		 * comprise a valid table must be 0.
+		 */
+		ext_tablep = (u32 *)ext_header;
 
-		i = ext_table_size / DWSIZE;
+		i = ext_table_size / sizeof(u32);
 		while (i--)
 			ext_table_sum += ext_tablep[i];
+
 		if (ext_table_sum) {
 			if (print_err)
-				pr_warn("aborting, bad extended signature table checksum\n");
+				pr_warn("Bad extended signature table checksum, aborting.\n");
 			return -EINVAL;
 		}
 	}
 
-	/* calculate the checksum */
+	/*
+	 * Calculate the checksum of update data and header. The checksum of
+	 * valid update data and header including the extended signature table
+	 * must be 0.
+	 */
 	orig_sum = 0;
-	i = (MC_HEADER_SIZE + data_size) / DWSIZE;
+	i = (MC_HEADER_SIZE + data_size) / sizeof(u32);
 	while (i--)
-		orig_sum += ((int *)mc)[i];
+		orig_sum += ((u32 *)mc)[i];
+
 	if (orig_sum) {
 		if (print_err)
-			pr_err("aborting, bad checksum\n");
+			pr_err("Bad microcode data checksum, aborting.\n");
 		return -EINVAL;
 	}
+
 	if (!ext_table_size)
 		return 0;
-	/* check extended signature checksum */
+
+	/*
+	 * Check extended signature checksum: 0 => valid.
+	 */
 	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);
+
+		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");
+				pr_err("Bad extended signature checksum, aborting.\n");
 			return -EINVAL;
 		}
 	}