cxl: Allow the kernel to trust that an image won't change on PERST.
Provide a kernel API and a sysfs entry which allow a user to specify
that when a card is PERSTed, it's image will stay the same, allowing
it to participate in EEH.
cxl_reset is used to reflash the card. In that case, we cannot safely
assert that the image will not change. Therefore, disallow cxl_reset
if the flag is set.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/Documentation/ABI/testing/sysfs-class-cxl b/Documentation/ABI/testing/sysfs-class-cxl
index acfe9df..b07e86d 100644
--- a/Documentation/ABI/testing/sysfs-class-cxl
+++ b/Documentation/ABI/testing/sysfs-class-cxl
@@ -223,3 +223,13 @@
Writing 1 will issue a PERST to card which may cause the card
to reload the FPGA depending on load_image_on_perst.
Users: https://github.com/ibm-capi/libcxl
+
+What: /sys/class/cxl/<card>/perst_reloads_same_image
+Date: July 2015
+Contact: linuxppc-dev@lists.ozlabs.org
+Description: read/write
+ Trust that when an image is reloaded via PERST, it will not
+ have changed.
+ 0 = don't trust, the image may be different (default)
+ 1 = trust that the image will not change.
+Users: https://github.com/ibm-capi/libcxl