Hi Jason,
On Wed, Aug 14, 2024 at 12:51:51PM -0300, Jason Gunthorpe wrote:
On Wed, Aug 14, 2024 at 02:56:33PM +0000, Mostafa Saleh wrote:
Also described in the pseudocode “SteIllegal()”
if eff_idr0_stall_model == '10' && STE.S2S == '0' then
// stall_model forcing stall, but S2S == 0
return TRUE;
This clips out an important bit:
if STE.Config == '11x' then
[..]
if eff_idr0_stall_model == '10' && STE.S2S == '0' then
// stall_model forcing stall, but S2S == 0
return TRUE;
And here we are using STRTAB_STE_0_CFG_S1_TRANS which is 101 and won't
match the STE.Config qualification.
The plain text language said the S2S is only required if the S2 is
translating, STRTAB_STE_0_CFG_S1_TRANS puts it in bypass.
Yes, my bad, this should be for stage-2 only which is populated in
arm_smmu_make_s2_domain_ste()
+ /*
+ * S2S is ignored if stage-2 exists but not enabled.
+ * S2S is not compatible with ATS.
+ */
+ if (master->stall_enabled && !ats_enabled &&
+ smmu->features & ARM_SMMU_FEAT_TRANS_S2)
+ target->data[2] |= STRTAB_STE_2_S2S;
We can't ignore ATS if it was requested here.