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authorWill Deacon <will@kernel.org>2022-07-25 10:59:15 +0100
committerWill Deacon <will@kernel.org>2022-07-25 10:59:15 +0100
commitf96d67a8af7a39f7ffaac464d8bccc4c720e52c2 (patch)
treedaee5c1458a5d8ed1bdb58b54de19b232ebd44aa /arch/arm64/kernel/hyp-stub.S
parent92867739e3439ecc9bfa0a106be515d93f14c735 (diff)
parent1191b6256e50a07e7d8ce36eb970708e42a4be1a (diff)
downloadlinux-f96d67a8af7a39f7ffaac464d8bccc4c720e52c2.tar.bz2
Merge branch 'for-next/boot' into for-next/core
* for-next/boot: (34 commits) arm64: fix KASAN_INLINE arm64: Add an override for ID_AA64SMFR0_EL1.FA64 arm64: Add the arm64.nosve command line option arm64: Add the arm64.nosme command line option arm64: Expose a __check_override primitive for oddball features arm64: Allow the idreg override to deal with variable field width arm64: Factor out checking of a feature against the override into a macro arm64: Allow sticky E2H when entering EL1 arm64: Save state of HCR_EL2.E2H before switch to EL1 arm64: Rename the VHE switch to "finalise_el2" arm64: mm: fix booting with 52-bit address space arm64: head: remove __PHYS_OFFSET arm64: lds: use PROVIDE instead of conditional definitions arm64: setup: drop early FDT pointer helpers arm64: head: avoid relocating the kernel twice for KASLR arm64: kaslr: defer initialization to initcall where permitted arm64: head: record CPU boot mode after enabling the MMU arm64: head: populate kernel page tables with MMU and caches on arm64: head: factor out TTBR1 assignment into a macro arm64: idreg-override: use early FDT mapping in ID map ...
Diffstat (limited to 'arch/arm64/kernel/hyp-stub.S')
-rw-r--r--arch/arm64/kernel/hyp-stub.S117
1 files changed, 90 insertions, 27 deletions
diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S
index 43d212618834..12c7fad02ae5 100644
--- a/arch/arm64/kernel/hyp-stub.S
+++ b/arch/arm64/kernel/hyp-stub.S
@@ -16,6 +16,30 @@
#include <asm/ptrace.h>
#include <asm/virt.h>
+// Warning, hardcoded register allocation
+// This will clobber x1 and x2, and expect x1 to contain
+// the id register value as read from the HW
+.macro __check_override idreg, fld, width, pass, fail
+ ubfx x1, x1, #\fld, #\width
+ cbz x1, \fail
+
+ adr_l x1, \idreg\()_override
+ ldr x2, [x1, FTR_OVR_VAL_OFFSET]
+ ldr x1, [x1, FTR_OVR_MASK_OFFSET]
+ ubfx x2, x2, #\fld, #\width
+ ubfx x1, x1, #\fld, #\width
+ cmp x1, xzr
+ and x2, x2, x1
+ csinv x2, x2, xzr, ne
+ cbnz x2, \pass
+ b \fail
+.endm
+
+.macro check_override idreg, fld, pass, fail
+ mrs x1, \idreg\()_el1
+ __check_override \idreg \fld 4 \pass \fail
+.endm
+
.text
.pushsection .hyp.text, "ax"
@@ -51,8 +75,8 @@ SYM_CODE_START_LOCAL(elx_sync)
msr vbar_el2, x1
b 9f
-1: cmp x0, #HVC_VHE_RESTART
- b.eq mutate_to_vhe
+1: cmp x0, #HVC_FINALISE_EL2
+ b.eq __finalise_el2
2: cmp x0, #HVC_SOFT_RESTART
b.ne 3f
@@ -73,27 +97,67 @@ SYM_CODE_START_LOCAL(elx_sync)
eret
SYM_CODE_END(elx_sync)
-// nVHE? No way! Give me the real thing!
-SYM_CODE_START_LOCAL(mutate_to_vhe)
+SYM_CODE_START_LOCAL(__finalise_el2)
+ check_override id_aa64pfr0 ID_AA64PFR0_SVE_SHIFT .Linit_sve .Lskip_sve
+
+.Linit_sve: /* SVE register access */
+ mrs x0, cptr_el2 // Disable SVE traps
+ bic x0, x0, #CPTR_EL2_TZ
+ msr cptr_el2, x0
+ isb
+ mov x1, #ZCR_ELx_LEN_MASK // SVE: Enable full vector
+ msr_s SYS_ZCR_EL2, x1 // length for EL1.
+
+.Lskip_sve:
+ check_override id_aa64pfr1 ID_AA64PFR1_SME_SHIFT .Linit_sme .Lskip_sme
+
+.Linit_sme: /* SME register access and priority mapping */
+ mrs x0, cptr_el2 // Disable SME traps
+ bic x0, x0, #CPTR_EL2_TSM
+ msr cptr_el2, x0
+ isb
+
+ mrs x1, sctlr_el2
+ orr x1, x1, #SCTLR_ELx_ENTP2 // Disable TPIDR2 traps
+ msr sctlr_el2, x1
+ isb
+
+ mov x0, #0 // SMCR controls
+
+ // Full FP in SM?
+ mrs_s x1, SYS_ID_AA64SMFR0_EL1
+ __check_override id_aa64smfr0 ID_AA64SMFR0_EL1_FA64_SHIFT 1 .Linit_sme_fa64 .Lskip_sme_fa64
+
+.Linit_sme_fa64:
+ orr x0, x0, SMCR_ELx_FA64_MASK
+.Lskip_sme_fa64:
+
+ orr x0, x0, #SMCR_ELx_LEN_MASK // Enable full SME vector
+ msr_s SYS_SMCR_EL2, x0 // length for EL1.
+
+ mrs_s x1, SYS_SMIDR_EL1 // Priority mapping supported?
+ ubfx x1, x1, #SMIDR_EL1_SMPS_SHIFT, #1
+ cbz x1, .Lskip_sme
+
+ msr_s SYS_SMPRIMAP_EL2, xzr // Make all priorities equal
+
+ mrs x1, id_aa64mmfr1_el1 // HCRX_EL2 present?
+ ubfx x1, x1, #ID_AA64MMFR1_HCX_SHIFT, #4
+ cbz x1, .Lskip_sme
+
+ mrs_s x1, SYS_HCRX_EL2
+ orr x1, x1, #HCRX_EL2_SMPME_MASK // Enable priority mapping
+ msr_s SYS_HCRX_EL2, x1
+
+.Lskip_sme:
+
+ // nVHE? No way! Give me the real thing!
// Sanity check: MMU *must* be off
mrs x1, sctlr_el2
tbnz x1, #0, 1f
// Needs to be VHE capable, obviously
- mrs x1, id_aa64mmfr1_el1
- ubfx x1, x1, #ID_AA64MMFR1_VHE_SHIFT, #4
- cbz x1, 1f
-
- // Check whether VHE is disabled from the command line
- adr_l x1, id_aa64mmfr1_override
- ldr x2, [x1, FTR_OVR_VAL_OFFSET]
- ldr x1, [x1, FTR_OVR_MASK_OFFSET]
- ubfx x2, x2, #ID_AA64MMFR1_VHE_SHIFT, #4
- ubfx x1, x1, #ID_AA64MMFR1_VHE_SHIFT, #4
- cmp x1, xzr
- and x2, x2, x1
- csinv x2, x2, xzr, ne
- cbnz x2, 2f
+ check_override id_aa64mmfr1 ID_AA64MMFR1_VHE_SHIFT 2f 1f
1: mov_q x0, HVC_STUB_ERR
eret
@@ -140,10 +204,10 @@ SYM_CODE_START_LOCAL(mutate_to_vhe)
msr spsr_el1, x0
b enter_vhe
-SYM_CODE_END(mutate_to_vhe)
+SYM_CODE_END(__finalise_el2)
// At the point where we reach enter_vhe(), we run with
- // the MMU off (which is enforced by mutate_to_vhe()).
+ // the MMU off (which is enforced by __finalise_el2()).
// We thus need to be in the idmap, or everything will
// explode when enabling the MMU.
@@ -222,12 +286,12 @@ SYM_FUNC_START(__hyp_reset_vectors)
SYM_FUNC_END(__hyp_reset_vectors)
/*
- * Entry point to switch to VHE if deemed capable
+ * Entry point to finalise EL2 and switch to VHE if deemed capable
+ *
+ * w0: boot mode, as returned by init_kernel_el()
*/
-SYM_FUNC_START(switch_to_vhe)
+SYM_FUNC_START(finalise_el2)
// Need to have booted at EL2
- adr_l x1, __boot_cpu_mode
- ldr w0, [x1]
cmp w0, #BOOT_CPU_MODE_EL2
b.ne 1f
@@ -236,9 +300,8 @@ SYM_FUNC_START(switch_to_vhe)
cmp x0, #CurrentEL_EL1
b.ne 1f
- // Turn the world upside down
- mov x0, #HVC_VHE_RESTART
+ mov x0, #HVC_FINALISE_EL2
hvc #0
1:
ret
-SYM_FUNC_END(switch_to_vhe)
+SYM_FUNC_END(finalise_el2)