intel_reg_read: add a flag to simplify bit decoding

This allows to specify '-d' parameter which will decode individual bits in
each register being read.

The register bits are printed horizontally for space reasons. This
requires more than 80x25 terminal to see them all. An alternative solution
would be to print them vertically, but this will become much more
difficult to read when printing multiple registers at the same time.

v2: fix spacing to get us a bit closer to the code nirvana.

Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>

1 files changed, 23 insertions, 2 deletions

diff --git a/tools/intel_reg_read.c b/tools/intel_reg_read.c
index 5f94fed1..6187a4be 100644
--- a/tools/intel_reg_read.c
+++ b/tools/intel_reg_read.c
@@ -32,6 +32,19 @@
 #include <string.h>
 #include "intel_gpu_tools.h"
 
+static void bit_decode(uint32_t reg)
+{
+	int i;
+
+	for (i=31; i >= 0; i--)
+		printf(" %2d", i);
+	printf("\n");
+
+	for (i=31; i >= 0; i--)
+		printf(" %2d", (reg & (1 << i)) && 1);
+	printf("\n");
+}
+
 static void dump_range(uint32_t start, uint32_t end)
 {
 	int i;
@@ -43,9 +56,10 @@ static void dump_range(uint32_t start, uint32_t end)
 
 static void usage(char *cmdname)
 {
-	printf("Usage: %s [-f] [addr1] [addr2] .. [addrN]\n", cmdname);
+	printf("Usage: %s [-f|-d] [addr1] [addr2] .. [addrN]\n", cmdname);
 	printf("\t -f : read back full range of registers.\n");
 	printf("\t      WARNING! This option may result in a machine hang!\n");
+	printf("\t -d : decode register bits.\n");
 	printf("\t addr : in 0xXXXX format\n");
 }
 
@@ -56,9 +70,13 @@ int main(int argc, char** argv)
 	int i, ch;
 	char *cmdname = strdup(argv[0]);
 	int full_dump = 0;
+	int decode_bits = 0;
 
-	while ((ch = getopt(argc, argv, "fh")) != -1) {
+	while ((ch = getopt(argc, argv, "dfh")) != -1) {
 		switch(ch) {
+		case 'd':
+			decode_bits = 1;
+			break;
 		case 'f':
 			full_dump = 1;
 			break;
@@ -98,6 +116,9 @@ int main(int argc, char** argv)
 		for (i=0; i < argc; i++) {
 			sscanf(argv[i], "0x%x", &reg);
 			dump_range(reg, reg + 4);
+
+			if (decode_bits)
+				bit_decode(*(volatile uint32_t *)((volatile char*)mmio + reg));
 		}
 	}