| /* |
| * 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> |
| #include <asm/virt.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 pgd |
| * x1: HYP stack |
| * x2: HYP vectors |
| */ |
| __do_hyp_init: |
| /* Check for a stub HVC call */ |
| cmp x0, #HVC_STUB_HCALL_NR |
| b.lo __kvm_handle_stub_hvc |
| |
| 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 |
| |
| /* |
| * Preserve all the RES1 bits while setting the default flags, |
| * as well as the EE bit on BE. Drop the A flag since the compiler |
| * is allowed to generate unaligned accesses. |
| */ |
| ldr x4, =(SCTLR_EL2_RES1 | (SCTLR_ELx_FLAGS & ~SCTLR_ELx_A)) |
| CPU_BE( orr x4, x4, #SCTLR_ELx_EE) |
| msr sctlr_el2, x4 |
| isb |
| |
| /* Set the stack and new vectors */ |
| kern_hyp_va x1 |
| mov sp, x1 |
| kern_hyp_va x2 |
| msr vbar_el2, x2 |
| |
| /* copy tpidr_el1 into tpidr_el2 for use by HYP */ |
| mrs x1, tpidr_el1 |
| msr tpidr_el2, x1 |
| |
| /* Hello, World! */ |
| eret |
| ENDPROC(__kvm_hyp_init) |
| |
| ENTRY(__kvm_handle_stub_hvc) |
| cmp x0, #HVC_SOFT_RESTART |
| b.ne 1f |
| |
| /* This is where we're about to jump, staying at EL2 */ |
| msr elr_el2, x1 |
| mov x0, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT | PSR_MODE_EL2h) |
| msr spsr_el2, x0 |
| |
| /* Shuffle the arguments, and don't come back */ |
| mov x0, x2 |
| mov x1, x3 |
| mov x2, x4 |
| b reset |
| |
| 1: cmp x0, #HVC_RESET_VECTORS |
| b.ne 1f |
| reset: |
| /* |
| * Reset kvm back to the hyp stub. Do not clobber x0-x4 in |
| * case we coming via HVC_SOFT_RESTART. |
| */ |
| mrs x5, sctlr_el2 |
| ldr x6, =SCTLR_ELx_FLAGS |
| bic x5, x5, x6 // Clear SCTL_M and etc |
| pre_disable_mmu_workaround |
| msr sctlr_el2, x5 |
| isb |
| |
| /* Install stub vectors */ |
| adr_l x5, __hyp_stub_vectors |
| msr vbar_el2, x5 |
| mov x0, xzr |
| eret |
| |
| 1: /* Bad stub call */ |
| ldr x0, =HVC_STUB_ERR |
| eret |
| |
| ENDPROC(__kvm_handle_stub_hvc) |
| |
| .ltorg |
| |
| .popsection |