diff options
Diffstat (limited to 'lib/xlat_tables_v2/aarch64/enable_mmu.S')
-rw-r--r-- | lib/xlat_tables_v2/aarch64/enable_mmu.S | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/lib/xlat_tables_v2/aarch64/enable_mmu.S b/lib/xlat_tables_v2/aarch64/enable_mmu.S new file mode 100644 index 0000000..9f075e4 --- /dev/null +++ b/lib/xlat_tables_v2/aarch64/enable_mmu.S @@ -0,0 +1,97 @@ +/* + * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <asm_macros.S> +#include <assert_macros.S> +#include <lib/xlat_tables/xlat_tables_v2.h> + + .global enable_mmu_direct_el1 + .global enable_mmu_direct_el2 + .global enable_mmu_direct_el3 + + /* Macros to read and write to system register for a given EL. */ + .macro _msr reg_name, el, gp_reg + msr \reg_name\()_el\()\el, \gp_reg + .endm + + .macro _mrs gp_reg, reg_name, el + mrs \gp_reg, \reg_name\()_el\()\el + .endm + + .macro tlbi_invalidate_all el + .if \el == 1 + TLB_INVALIDATE(vmalle1) + .elseif \el == 2 + TLB_INVALIDATE(alle2) + .elseif \el == 3 + TLB_INVALIDATE(alle3) + .else + .error "EL must be 1, 2 or 3" + .endif + .endm + + /* void enable_mmu_direct_el<x>(unsigned int flags) */ + .macro define_mmu_enable_func el + func enable_mmu_direct_\()el\el +#if ENABLE_ASSERTIONS + _mrs x1, sctlr, \el + tst x1, #SCTLR_M_BIT + ASM_ASSERT(eq) +#endif + /* Invalidate all TLB entries */ + tlbi_invalidate_all \el + + mov x7, x0 + adrp x0, mmu_cfg_params + add x0, x0, :lo12:mmu_cfg_params + + /* MAIR */ + ldr x1, [x0, #(MMU_CFG_MAIR << 3)] + _msr mair, \el, x1 + + /* TCR */ + ldr x2, [x0, #(MMU_CFG_TCR << 3)] + _msr tcr, \el, x2 + + /* TTBR */ + ldr x3, [x0, #(MMU_CFG_TTBR0 << 3)] + _msr ttbr0, \el, x3 + + /* + * Ensure all translation table writes have drained into memory, the TLB + * invalidation is complete, and translation register writes are + * committed before enabling the MMU + */ + dsb ish + isb + + /* Set and clear required fields of SCTLR */ + _mrs x4, sctlr, \el + mov_imm x5, SCTLR_WXN_BIT | SCTLR_C_BIT | SCTLR_M_BIT + orr x4, x4, x5 + + /* Additionally, amend SCTLR fields based on flags */ + bic x5, x4, #SCTLR_C_BIT + tst x7, #DISABLE_DCACHE + csel x4, x5, x4, ne + + _msr sctlr, \el, x4 + isb + + ret + endfunc enable_mmu_direct_\()el\el + .endm + + /* + * Define MMU-enabling functions for EL1, EL2 and EL3: + * + * enable_mmu_direct_el1 + * enable_mmu_direct_el2 + * enable_mmu_direct_el3 + */ + define_mmu_enable_func 1 + define_mmu_enable_func 2 + define_mmu_enable_func 3 |