1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2016 - ARM Ltd
4  *
5  * stage2 page table helpers
6  */
7 
8 #ifndef __ARM64_S2_PGTABLE_H_
9 #define __ARM64_S2_PGTABLE_H_
10 
11 #include <linux/pgtable.h>
12 
13 /*
14  * The hardware supports concatenation of up to 16 tables at stage2 entry
15  * level and we use the feature whenever possible, which means we resolve 4
16  * additional bits of address at the entry level.
17  *
18  * This implies, the total number of page table levels required for
19  * IPA_SHIFT at stage2 expected by the hardware can be calculated using
20  * the same logic used for the (non-collapsable) stage1 page tables but for
21  * (IPA_SHIFT - 4).
22  */
23 #define stage2_pgtable_levels(ipa)	ARM64_HW_PGTABLE_LEVELS((ipa) - 4)
24 #define kvm_stage2_levels(mmu)		VTCR_EL2_LVLS((mmu)->vtcr)
25 
26 /*
27  * kvm_mmmu_cache_min_pages() is the number of pages required to install
28  * a stage-2 translation. We pre-allocate the entry level page table at
29  * the VM creation.
30  */
31 #define kvm_mmu_cache_min_pages(mmu)	(kvm_stage2_levels(mmu) - 1)
32 
33 #endif	/* __ARM64_S2_PGTABLE_H_ */
34