1 /* SPDX-License-Identifier: GPL-2.0-only */
5 * Copyright (C) 2012 ARM Ltd.
6 * Author: Marc Zyngier <marc.zyngier@arm.com>
9 #include <linux/init.h>
10 #include <linux/linkage.h>
12 #include <asm/assembler.h>
13 #include <asm/el2_setup.h>
14 #include <asm/kvm_arm.h>
15 #include <asm/kvm_asm.h>
16 #include <asm/ptrace.h>
19 // Warning, hardcoded register allocation
20 // This will clobber x1 and x2.
21 .macro check_override idreg, fld, pass, fail
23 ubfx x1, x1, #\fld, #4
26 adr_l x1, \idreg\()_override
27 ldr x2, [x1, FTR_OVR_VAL_OFFSET]
28 ldr x1, [x1, FTR_OVR_MASK_OFFSET]
29 ubfx x2, x2, #\fld, #4
30 ubfx x1, x1, #\fld, #4
39 .pushsection .hyp.text, "ax"
43 SYM_CODE_START(__hyp_stub_vectors)
44 ventry el2_sync_invalid // Synchronous EL2t
45 ventry el2_irq_invalid // IRQ EL2t
46 ventry el2_fiq_invalid // FIQ EL2t
47 ventry el2_error_invalid // Error EL2t
49 ventry elx_sync // Synchronous EL2h
50 ventry el2_irq_invalid // IRQ EL2h
51 ventry el2_fiq_invalid // FIQ EL2h
52 ventry el2_error_invalid // Error EL2h
54 ventry elx_sync // Synchronous 64-bit EL1
55 ventry el1_irq_invalid // IRQ 64-bit EL1
56 ventry el1_fiq_invalid // FIQ 64-bit EL1
57 ventry el1_error_invalid // Error 64-bit EL1
59 ventry el1_sync_invalid // Synchronous 32-bit EL1
60 ventry el1_irq_invalid // IRQ 32-bit EL1
61 ventry el1_fiq_invalid // FIQ 32-bit EL1
62 ventry el1_error_invalid // Error 32-bit EL1
63 SYM_CODE_END(__hyp_stub_vectors)
67 SYM_CODE_START_LOCAL(elx_sync)
68 cmp x0, #HVC_SET_VECTORS
73 1: cmp x0, #HVC_FINALISE_EL2
76 2: cmp x0, #HVC_SOFT_RESTART
84 3: cmp x0, #HVC_RESET_VECTORS
85 beq 9f // Nothing to reset!
87 /* Someone called kvm_call_hyp() against the hyp-stub... */
88 mov_q x0, HVC_STUB_ERR
93 SYM_CODE_END(elx_sync)
95 SYM_CODE_START_LOCAL(__finalise_el2)
96 // nVHE? No way! Give me the real thing!
97 // Sanity check: MMU *must* be off
101 // Needs to be VHE capable, obviously
102 check_override id_aa64mmfr1 ID_AA64MMFR1_VHE_SHIFT 2f 1f
104 1: mov_q x0, HVC_STUB_ERR
107 // Engage the VHE magic!
108 mov_q x0, HCR_HOST_VHE_FLAGS
112 // Use the EL1 allocated stack, per-cpu offset
118 // FP configuration, vectors
119 mrs_s x0, SYS_CPACR_EL12
121 mrs_s x0, SYS_VBAR_EL12
124 // Use EL2 translations for SPE & TRBE and disable access from EL1
126 bic x0, x0, #(MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT)
127 bic x0, x0, #(MDCR_EL2_E2TB_MASK << MDCR_EL2_E2TB_SHIFT)
130 // Transfer the MM state from EL1 to EL2
131 mrs_s x0, SYS_TCR_EL12
133 mrs_s x0, SYS_TTBR0_EL12
135 mrs_s x0, SYS_TTBR1_EL12
137 mrs_s x0, SYS_MAIR_EL12
141 // Hack the exception return to stay at EL2
143 and x0, x0, #~PSR_MODE_MASK
144 mov x1, #PSR_MODE_EL2h
149 SYM_CODE_END(__finalise_el2)
151 // At the point where we reach enter_vhe(), we run with
152 // the MMU off (which is enforced by __finalise_el2()).
153 // We thus need to be in the idmap, or everything will
154 // explode when enabling the MMU.
156 .pushsection .idmap.text, "ax"
158 SYM_CODE_START_LOCAL(enter_vhe)
159 // Invalidate TLBs before enabling the MMU
164 // Enable the EL2 S1 MMU, as set up from EL1
165 mrs_s x0, SYS_SCTLR_EL12
168 // Disable the EL1 S1 MMU for a good measure
169 mov_q x0, INIT_SCTLR_EL1_MMU_OFF
170 msr_s SYS_SCTLR_EL12, x0
175 SYM_CODE_END(enter_vhe)
179 .macro invalid_vector label
180 SYM_CODE_START_LOCAL(\label)
185 invalid_vector el2_sync_invalid
186 invalid_vector el2_irq_invalid
187 invalid_vector el2_fiq_invalid
188 invalid_vector el2_error_invalid
189 invalid_vector el1_sync_invalid
190 invalid_vector el1_irq_invalid
191 invalid_vector el1_fiq_invalid
192 invalid_vector el1_error_invalid
197 * __hyp_set_vectors: Call this after boot to set the initial hypervisor
198 * vectors as part of hypervisor installation. On an SMP system, this should
199 * be called on each CPU.
201 * x0 must be the physical address of the new vector table, and must be
204 * Before calling this, you must check that the stub hypervisor is installed
205 * everywhere, by waiting for any secondary CPUs to be brought up and then
206 * checking that is_hyp_mode_available() is true.
208 * If not, there is a pre-existing hypervisor, some CPUs failed to boot, or
209 * something else went wrong... in such cases, trying to install a new
210 * hypervisor is unlikely to work as desired.
212 * When you call into your shiny new hypervisor, sp_el2 will contain junk,
213 * so you will need to set that to something sensible at the new hypervisor's
214 * initialisation entry point.
217 SYM_FUNC_START(__hyp_set_vectors)
219 mov x0, #HVC_SET_VECTORS
222 SYM_FUNC_END(__hyp_set_vectors)
224 SYM_FUNC_START(__hyp_reset_vectors)
225 mov x0, #HVC_RESET_VECTORS
228 SYM_FUNC_END(__hyp_reset_vectors)
231 * Entry point to finalise EL2 and switch to VHE if deemed capable
233 * w0: boot mode, as returned by init_kernel_el()
235 SYM_FUNC_START(finalise_el2)
236 // Need to have booted at EL2
237 cmp w0, #BOOT_CPU_MODE_EL2
240 // and still be at EL1
242 cmp x0, #CurrentEL_EL1
245 mov x0, #HVC_FINALISE_EL2
249 SYM_FUNC_END(finalise_el2)