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