[PATCH 13/14] intel_l3_parity: Support error injection

Ben Widawsky
2013-09-18T04:13:31Z

Haswell added the ability to inject errors which is extremely useful for
testing. Add two arguments to the tool to inject, and uninject.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
---
tests/sysfs_l3_parity | 2 +-
tools/intel_l3_parity.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 68 insertions(+), 3 deletions(-)

diff --git a/tests/sysfs_l3_parity b/tests/sysfs_l3_parity
index a0dfad9..e9d4411 100755
--- a/tests/sysfs_l3_parity
+++ b/tests/sysfs_l3_parity
@@ -21,7 +21,7 @@ fi
$SOURCE_DIR/../tools/intel_l3_parity -r 0 -b 0 -s 0 -e

#Check that we can clear remaps
-if [ `$SOURCE_DIR/../tools/intel_l3_parity -l | wc -c` != "0" ] ; then
+if [ `$SOURCE_DIR/../tools/intel_l3_parity -l | wc -l` != 1 ] ; then
echo "Fail 2"
exit 1
fi
diff --git a/tools/intel_l3_parity.c b/tools/intel_l3_parity.c
index ed7034a..d2ad3c9 100644
--- a/tools/intel_l3_parity.c
+++ b/tools/intel_l3_parity.c
@@ -79,6 +79,20 @@ static int which_slice = -1;
(__i) < ((which_slice == -1) ? MAX_SLICES : (which_slice + 1)); \
(__i)++)

+static void decode_dft(uint32_t dft)
+{
+ if (IS_IVYBRIDGE(devid) || !(dft & 1)) {
+ printf("Error injection disabled\n");
+ return;
+ }
+ printf("Error injection enabled\n");
+ printf(" Hang = %s\n", (dft >> 28) & 0x1 ? "yes" : "no");
+ printf(" Row = %d\n", (dft >> 7) & 0x7ff);
+ printf(" Bank = %d\n", (dft >> 2) & 0x3);
+ printf(" Subbank = %d\n", (dft >> 4) & 0x7);
+ printf(" Slice = %d\n", (dft >> 1) & 0x1);
+}
+
static void dumpit(int slice)
{
int i, j;
@@ -150,7 +164,9 @@ static void usage(const char *name)
" -l, --list List the current L3 logs\n"
" -a, --clear-all Clear all disabled rows\n"
" -e, --enable Enable row, bank, subbank (undo -d)\n"
- " -d, --disable=<row,bank,subbank> Disable row, bank, subbank (inline arguments are deprecated. Please use -r, -b, -s instead\n",
+ " -d, --disable=<row,bank,subbank> Disable row, bank, subbank (inline arguments are deprecated. Please use -r, -b, -s instead\n"
+ " -i, --inject [HSW only] Cause hardware to inject a row errors\n"
+ " -u, --uninject [HSW only] Turn off hardware error injectection (undo -i)\n",
name);
}

@@ -158,6 +174,7 @@ int main(int argc, char *argv[])
{
const int device = drm_get_card();
char *path[REAL_MAX_SLICES];
+ uint32_t dft;
int row = 0, bank = 0, sbank = 0;
int fd[REAL_MAX_SLICES] = {0}, ret, i;
int action = '0';
@@ -167,6 +184,8 @@ int main(int argc, char *argv[])
if (intel_gen(devid) < 7 || IS_VALLEYVIEW(devid))
exit(EXIT_SUCCESS);

+ assert(intel_register_access_init(intel_get_pci_device(), 0) == 0);
+
ret = asprintf(&path[0], "/sys/class/drm/card%d/l3_parity", device);
assert(ret != -1);
ret = asprintf(&path[1], "/sys/class/drm/card%d/l3_parity_slice_1", device);
@@ -183,6 +202,7 @@ int main(int argc, char *argv[])
assert(lseek(fd[i], 0, SEEK_SET) == 0);
}

+ dft = intel_register_read(0xb038);

while (1) {
int c, option_index = 0;
@@ -192,6 +212,8 @@ int main(int argc, char *argv[])
{ "clear-all", no_argument, 0, 'a' },
{ "enable", no_argument, 0, 'e' },
{ "disable", optional_argument, 0, 'd' },
+ { "inject", no_argument, 0, 'i' },
+ { "uninject", no_argument, 0, 'u' },
{ "hw-info", no_argument, 0, 'H' },
{ "row", required_argument, 0, 'r' },
{ "bank", required_argument, 0, 'b' },
@@ -200,7 +222,7 @@ int main(int argc, char *argv[])
{0, 0, 0, 0}
};

- c = getopt_long(argc, argv, "hHr:b:s:w:aled::", long_options,
+ c = getopt_long(argc, argv, "hHr:b:s:w:aled::iu", long_options,
&option_index);
if (c == -1)
break;
@@ -215,6 +237,7 @@ int main(int argc, char *argv[])
printf("Number of banks: %d\n", num_banks());
printf("Subbanks per bank: %d\n", NUM_SUBBANKS);
printf("Max L3 size: %dK\n", L3_SIZE >> 10);
+ printf("Has error injection: %s\n", IS_HASWELL(devid) ? "yes" : "no");
exit(EXIT_SUCCESS);
case 'r':
row = atoi(optarg);
@@ -236,6 +259,12 @@ int main(int argc, char *argv[])
if (which_slice >= MAX_SLICES)
exit(EXIT_FAILURE);
break;
+ case 'i':
+ case 'u':
+ if (!IS_HASWELL(devid)) {
+ fprintf(stderr, "Error injection supported on HSW+ only\n");
+ exit(EXIT_FAILURE);
+ }
case 'd':
if (optarg) {
ret = sscanf(optarg, "%d,%d,%d", &row, &bank, &sbank);
@@ -256,6 +285,23 @@ int main(int argc, char *argv[])
}
}

+ if (action == 'i') {
+ if (((dft >> 1) & 1) != which_slice) {
+ fprintf(stderr, "DFT register already has slice %d enabled, and we don't support multiple slices. Try modifying -w; but sometimes the register sticks in the wrong way\n", (dft >> 1) & 1);
+ exit(EXIT_FAILURE);
+ }
+
+ if (which_slice == -1) {
+ fprintf(stderr, "Cannot inject errors to multiple slices (modify -w)\n");
+ exit(EXIT_FAILURE);
+ }
+ if (dft & 1 && ((dft >> 1) && 1) == which_slice)
+ printf("warning: overwriting existing injections. This is very dangerous.\n");
+ }
+
+ if (action == 'l')
+ decode_dft(dft);
+
/* Per slice operations */
for_each_slice(i) {
switch (action) {
@@ -271,11 +317,30 @@ int main(int argc, char *argv[])
case 'd':
assert(disable_rbs(row, bank, sbank, i) == 0);
break;
+ case 'i':
+ if (bank == 3) {
+ fprintf(stderr, "The hardware does not support error inject on bank 3.\n");
+ exit(EXIT_FAILURE);
+ }
+ dft |= row << 7;
+ dft |= sbank << 4;
+ dft |= bank << 2;
+ assert(i < 2);
+ dft |= i << 1; /* slice */
+ dft |= 1 << 0; /* enable */
+ intel_register_write(0xb038, dft);
+ break;
+ case 'u':
+ intel_register_write(0xb038, dft & ~(1<<0));
+ break;
+ case 'L':
+ break;
default:
abort();
}
}

+ intel_register_access_fini();
if (action == 'l')
exit(EXIT_SUCCESS);

--
1.8.4