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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 | /* * Copyright (C) 2012,2013 - ARM Ltd * Author: Marc Zyngier <marc.zyngier@arm.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License, version 2, as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <linux/linkage.h> #include <asm/assembler.h> #include <asm/kvm_arm.h> #include <asm/kvm_mmu.h> #include <asm/pgtable-hwdef.h> #include <asm/sysreg.h> .text .pushsection .hyp.idmap.text, "ax" .align 11 ENTRY(__kvm_hyp_init) ventry __invalid // Synchronous EL2t ventry __invalid // IRQ EL2t ventry __invalid // FIQ EL2t ventry __invalid // Error EL2t ventry __invalid // Synchronous EL2h ventry __invalid // IRQ EL2h ventry __invalid // FIQ EL2h ventry __invalid // Error EL2h ventry __do_hyp_init // Synchronous 64-bit EL1 ventry __invalid // IRQ 64-bit EL1 ventry __invalid // FIQ 64-bit EL1 ventry __invalid // Error 64-bit EL1 ventry __invalid // Synchronous 32-bit EL1 ventry __invalid // IRQ 32-bit EL1 ventry __invalid // FIQ 32-bit EL1 ventry __invalid // Error 32-bit EL1 __invalid: b . /* * x0: HYP boot pgd * x1: HYP pgd * x2: HYP stack * x3: HYP vectors */ __do_hyp_init: msr ttbr0_el2, x0 mrs x4, tcr_el1 ldr x5, =TCR_EL2_MASK and x4, x4, x5 mov x5, #TCR_EL2_RES1 orr x4, x4, x5 #ifndef CONFIG_ARM64_VA_BITS_48 /* * If we are running with VA_BITS < 48, we may be running with an extra * level of translation in the ID map. This is only the case if system * RAM is out of range for the currently configured page size and number * of translation levels, in which case we will also need the extra * level for the HYP ID map, or we won't be able to enable the EL2 MMU. * * However, at EL2, there is only one TTBR register, and we can't switch * between translation tables *and* update TCR_EL2.T0SZ at the same * time. Bottom line: we need the extra level in *both* our translation * tables. * * So use the same T0SZ value we use for the ID map. */ ldr_l x5, idmap_t0sz bfi x4, x5, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH #endif /* * Read the PARange bits from ID_AA64MMFR0_EL1 and set the PS bits in * TCR_EL2. */ mrs x5, ID_AA64MMFR0_EL1 bfi x4, x5, #16, #3 msr tcr_el2, x4 mrs x4, mair_el1 msr mair_el2, x4 isb /* Invalidate the stale TLBs from Bootloader */ tlbi alle2 dsb sy mrs x4, sctlr_el2 and x4, x4, #SCTLR_ELx_EE // preserve endianness of EL2 ldr x5, =SCTLR_ELx_FLAGS orr x4, x4, x5 msr sctlr_el2, x4 isb /* Skip the trampoline dance if we merged the boot and runtime PGDs */ cmp x0, x1 b.eq merged /* MMU is now enabled. Get ready for the trampoline dance */ ldr x4, =TRAMPOLINE_VA adr x5, target bfi x4, x5, #0, #PAGE_SHIFT br x4 target: /* We're now in the trampoline code, switch page tables */ msr ttbr0_el2, x1 isb /* Invalidate the old TLBs */ tlbi alle2 dsb sy merged: /* Set the stack and new vectors */ kern_hyp_va x2 mov sp, x2 kern_hyp_va x3 msr vbar_el2, x3 /* Hello, World! */ eret ENDPROC(__kvm_hyp_init) /* * Reset kvm back to the hyp stub. This is the trampoline dance in * reverse. If kvm used an extended idmap, __extended_idmap_trampoline * calls this code directly in the idmap. In this case switching to the * boot tables is a no-op. * * x0: HYP boot pgd * x1: HYP phys_idmap_start */ ENTRY(__kvm_hyp_reset) /* We're in trampoline code in VA, switch back to boot page tables */ msr ttbr0_el2, x0 isb /* Ensure the PA branch doesn't find a stale tlb entry or stale code. */ ic iallu tlbi alle2 dsb sy isb /* Branch into PA space */ adr x0, 1f bfi x1, x0, #0, #PAGE_SHIFT br x1 /* We're now in idmap, disable MMU */ 1: mrs x0, sctlr_el2 ldr x1, =SCTLR_ELx_FLAGS bic x0, x0, x1 // Clear SCTL_M and etc msr sctlr_el2, x0 isb /* Invalidate the old TLBs */ tlbi alle2 dsb sy /* Install stub vectors */ adr_l x0, __hyp_stub_vectors msr vbar_el2, x0 eret ENDPROC(__kvm_hyp_reset) .ltorg .popsection |