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ARM SMMU versions 1 and 2: Difference between revisions
→Context banks
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* MONC only pertains to contexts reserved for secure mode use. Non-secure contexts ignore and treat the MONC bit as 0. Set it to 0.
* Sign extension via SMMU_CBn_TCR2.SEP is ignored for MONC banks.
=== VHE EL2 Contexts (E2HC) (Section 2.10) ===
E2HC contexts are meant to be used by hypervisor guests running in pseudo-EL2 (ARM's VHE feature) on top of another hypervisor which is running in real-EL2. The SMMU can only be programmed to use either E2HC or HYPC, but not both at the same time. This is a decision which must be made globally and it affects all software using the SMMU whether secure or nonsecure, whether EL3, EL2 or EL1. In fact, the HYPC and E2HC bits are polymorphically at the same position in the register.
E2HC contexts must be programmed to be of SMMU_CBARn.TYPE of 0b01 (stage1 followed by stage2 bypass). Unlike HYPC however, the E2HC translation regime is split between two TTBR registers. See the TLB management section to understand how the TLB entries for E2HC are handled by the TLB.
== IRQs / SMMU Faults ==
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