Being able to cause a stage 1 data abort might be useful for future tests.
Add a function that unmaps a page from the translation tables.
Signed-off-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
---
lib/arm/asm/mmu-api.h | 1 +
lib/arm/mmu.c | 32 ++++++++++++++++++++++++++++++++
2 files changed, 33 insertions(+)
diff --git a/lib/arm/asm/mmu-api.h b/lib/arm/asm/mmu-api.h
index 2bbe1faea900..305f77c6501f 100644
--- a/lib/arm/asm/mmu-api.h
+++ b/lib/arm/asm/mmu-api.h
@@ -23,4 +23,5 @@ extern void mmu_set_range_ptes(pgd_t *pgtable, uintptr_t virt_offset,
phys_addr_t phys_start, phys_addr_t phys_end,
pgprot_t prot);
extern void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr);
+extern void mmu_unmap_page(pgd_t *pgtable, unsigned long vaddr);
#endif
diff --git a/lib/arm/mmu.c b/lib/arm/mmu.c
index 540a1e842d5b..72ac0be8d146 100644
--- a/lib/arm/mmu.c
+++ b/lib/arm/mmu.c
@@ -232,3 +232,35 @@ void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr)
out_flush_tlb:
flush_tlb_page(vaddr);
}
+
+void mmu_unmap_page(pgd_t *pgtable, unsigned long vaddr)
+{
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pte_t *pte;
+
+ if (!mmu_enabled())
+ return;
+
+ pgd = pgd_offset(pgtable, vaddr);
+ if (!pgd_valid(*pgd))
+ return;
+
+ pmd = pmd_offset(pgd, vaddr);
+ if (!pmd_valid(*pmd))
+ return;
+
+ if (pmd_huge(*pmd)) {
+ WRITE_ONCE(*pmd, 0);
+ goto out_flush_tlb;
+ } else {
+ pte = pte_offset(pmd, vaddr);
+ if (!pte_valid(*pte))
+ return;
+ WRITE_ONCE(*pte, 0);
+ goto out_flush_tlb;
+ }
+
+out_flush_tlb:
+ flush_tlb_page(vaddr);
+}
--
2.29.1
