On 7/12/2023 10:03, Ceraolo Spurio, Daniele wrote:
On 7/12/2023 3:03 AM, Andrzej Hajda wrote:
On 11.07.2023 22:31, Daniele Ceraolo Spurio wrote:
Due to a change in the auth flow on MTL, GuC 70.7.0 and newer will only
be able to authenticate HuC 8.5.1 and newer. The plan is to update
the 2
binaries sinchronously in linux-firmware so that the fw repo always has
synchronously
a matching pair that works; still, it's better to check in the
kernel so
we can print an error message and abort HuC loading if the binaries are
out of sync instead of failing the authentication.
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@xxxxxxxxx>
Cc: John Harrison <John.C.Harrison@xxxxxxxxx>
---
drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c | 42
++++++++++++++++++++++++
1 file changed, 42 insertions(+)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
index 08e16017584b..f0cc5bb47fa0 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
@@ -803,11 +803,53 @@ static int try_firmware_load(struct
intel_uc_fw *uc_fw, const struct firmware **
return 0;
}
+static int check_mtl_huc_guc_compatibility(struct intel_gt *gt,
+ struct intel_uc_fw_file *huc_selected)
+{
+ struct intel_uc_fw_file *guc_selected =
>->uc.guc.fw.file_selected;
+ struct intel_uc_fw_ver *huc_ver = &huc_selected->ver;
+ struct intel_uc_fw_ver *guc_ver = &guc_selected->ver;
+ bool new_huc;
+ bool new_guc;
Could put both of these bools on a single line.
+
+ /* we can only do this check after having fetched both GuC and
HuC */
+ GEM_BUG_ON(!huc_selected->path || !guc_selected->path);
+
+ /*
+ * Due to changes in the authentication flow for MTL, HuC 8.5.1
or newer
+ * requires GuC 70.7.0 or newer. Older HuC binaries will
instead require
+ * GuC < 70.7.0.
+ */
+ new_huc = huc_ver->major > 8 ||
+ (huc_ver->major == 8 && huc_ver->minor > 5) ||
+ (huc_ver->major == 8 && huc_ver->minor == 5 &&
huc_ver->patch >= 1);
+
+ new_guc = guc_ver->major > 70 ||
+ (guc_ver->major == 70 && guc_ver->minor >= 7);
Wouldn't be more readable to define sth like UC_VER_FULL(v)
then use UC_VER_FULL(huc_ver) >= IP_VER_FULL(8, 5, 1).
I am not sure if it is worth for two checks.
We've been trying to avoid those kind of macros because the version
would need to be a u64 under the hood (each version number is a u16)
and therefore type casting would be required to make all the shifting
work, which makes the macro nasty to look at and as you said IMO not
worth it for just 2 checks. Note that the GuC is the exception because
it guarantees its version fits in a u32, so there is some macro use in
the GuC-specific code.
Pretty sure I did originally try to go the u64 version route but it
caused a lot more problems than it solved. I forget the details but in
addition to all the extra casting mentioned above, I vaguely recall
there issues with 32bit compilers/architectures or some such. Hence we
only have the 8bit-per-version-component/32bit-merged macros that are
for use with the GuC version and only the GuC version.
Given that this is (hopefully) a one off hack to cope with a one off
bug, I would stick with the unrolled code rather than adding extra
complications.
+
+ if (new_huc != new_guc) {
+ UNEXPECTED(gt, "HuC %u.%u.%u is incompatible with GuC
%u.%u.%u\n",
+ huc_ver->major, huc_ver->minor, huc_ver->patch,
+ guc_ver->major, guc_ver->minor, guc_ver->patch);
+ gt_info(gt, "MTL GuC 70.7.0+ and HuC 8.5.1+ don't work with
older releases\n");
+ return -ENOEXEC;
+ }
+
+ return 0;
+}
+
int intel_uc_check_file_version(struct intel_uc_fw *uc_fw, bool
*old_ver)
{
struct intel_gt *gt = __uc_fw_to_gt(uc_fw);
struct intel_uc_fw_file *wanted = &uc_fw->file_wanted;
struct intel_uc_fw_file *selected = &uc_fw->file_selected;
+ int ret;
+
+ if (IS_METEORLAKE(gt->i915) && uc_fw->type ==
INTEL_UC_FW_TYPE_HUC) {
Moving this check inside check function would make it more generic,
up to you.
This will hopefully never apply to any other platform. This is a light
breach of the HuC compatibility contract, so I really don't want to
have a generic function to handle it. I want it to be clear from a
higher level that this is an exception for a specific platform. Maybe
worth adding a comment? Would something like the following make things
clearer?
/*
* MTL has some compatibility issues with early GuC/HuC binaries
* not working with newer ones. This is specific to MTL and we
* don't expect it to extend to other platforms.
*/
I agree with Daniele about keeping this the exception not the norm. The
comment works for me.
Typo in commit message and a declaration nit-pick but otherwise:
Reviewed-by: John Harrison <John.C.Harrison@xxxxxxxxx>
Daniele
Reviewed-by: Andrzej Hajda <andrzej.hajda@xxxxxxxxx>
Regards
Andrzej
+ ret = check_mtl_huc_guc_compatibility(gt, selected);
+ if (ret)
+ return ret;
+ }
if (!wanted->ver.major || !selected->ver.major)
return 0;
