platform/x86/intel/ifs: Add current_batch sysfs entry

Initial implementation assumed a single IFS test image file with a
fixed name ff-mm-ss.scan. (where ff, mm, ss refers to family, model and
stepping of the core).

Subsequently, it became evident that supporting more than one test
image file is needed to provide more comprehensive test coverage. (Test
coverage in this scenario refers to testing more transistors in the core
to identify faults).

The other alternative of increasing the size of a single scan test image
file would not work as the  upper bound is limited by the size of memory
area reserved by BIOS for loading IFS test image.

Introduce "current_batch" file which accepts a number. Writing a
number to the current_batch file would load the test image file by
name ff-mm-ss-<xy>.scan, where <xy> is the number written to the
"current_batch" file in hex. Range check of the input is done to verify
it not greater than 0xff.

For e.g if the scan test image comprises of 6 files, they would be named:

  06-8f-06-01.scan
  06-8f-06-02.scan
  06-8f-06-03.scan
  06-8f-06-04.scan
  06-8f-06-05.scan
  06-8f-06-06.scan

And writing 3 to current_batch would result in loading 06-8f-06-03.scan
above. The file can also be read to know the currently loaded file.

And testing a system looks like:

  for each scan file
  do
  	load the IFS test image file (write to the batch file)
  	for each core
  	do
  		test the core with this set of tests
  	done
  done

Qualify few error messages with the test image file suffix to provide
better context.

  [ bp: Massage commit message. Add link to the discussion. ]

Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20221107225323.2733518-13-jithu.joseph@intel.com

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/platform/x86/intel/ifs/runtest.c b/drivers/platform/x86/intel/ifs/runtest.c
index b2ca2bb4501f..0bfd8fcdd7e8 100644
--- a/drivers/platform/x86/intel/ifs/runtest.c
+++ b/drivers/platform/x86/intel/ifs/runtest.c
@@ -78,14 +78,16 @@ static void message_not_tested(struct device *dev, int cpu, union ifs_status sta
 
 static void message_fail(struct device *dev, int cpu, union ifs_status status)
 {
+	struct ifs_data *ifsd = ifs_get_data(dev);
+
 	/*
 	 * control_error is set when the microcode runs into a problem
 	 * loading the image from the reserved BIOS memory, or it has
 	 * been corrupted. Reloading the image may fix this issue.
 	 */
 	if (status.control_error) {
-		dev_err(dev, "CPU(s) %*pbl: could not execute from loaded scan image\n",
-			cpumask_pr_args(cpu_smt_mask(cpu)));
+		dev_err(dev, "CPU(s) %*pbl: could not execute from loaded scan image. Batch: %02x version: 0x%x\n",
+			cpumask_pr_args(cpu_smt_mask(cpu)), ifsd->cur_batch, ifsd->loaded_version);
 	}
 
 	/*
@@ -96,8 +98,8 @@ static void message_fail(struct device *dev, int cpu, union ifs_status status)
 	 * the core being tested.
 	 */
 	if (status.signature_error) {
-		dev_err(dev, "CPU(s) %*pbl: test signature incorrect.\n",
-			cpumask_pr_args(cpu_smt_mask(cpu)));
+		dev_err(dev, "CPU(s) %*pbl: test signature incorrect. Batch: %02x version: 0x%x\n",
+			cpumask_pr_args(cpu_smt_mask(cpu)), ifsd->cur_batch, ifsd->loaded_version);
 	}
 }