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| author | Marc Zyngier <maz@kernel.org> | 2022-06-30 19:04:55 +0300 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2022-07-01 17:22:51 +0300 |
| commit | fa8aa59ae6454b7a6a670acb2097e7800992cba1 (patch) | |
| tree | 3904c8d6a2770c0c6adb10916a5701c2347b6a92 /arch/arm64/kernel/hyp-stub.S | |
| parent | ae4b7e38e9a94798f08f5d66b02077900ab92903 (diff) | |
| download | linux-fa8aa59ae6454b7a6a670acb2097e7800992cba1.tar.xz | |
arm64: Factor out checking of a feature against the override into a macro
Checking for a feature being supported from assembly code is
a bit tedious if we need to factor in the idreg override.
Since we already have such code written for forcing nVHE, move
the whole thing into a macro. This heavily relies on the override
structure being called foo_override for foo_el1.
No functional change.
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220630160500.1536744-5-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/kernel/hyp-stub.S')
| -rw-r--r-- | arch/arm64/kernel/hyp-stub.S | 34 |
1 files changed, 20 insertions, 14 deletions
diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S index 571286eb443c..43c94e7a2c1d 100644 --- a/arch/arm64/kernel/hyp-stub.S +++ b/arch/arm64/kernel/hyp-stub.S @@ -16,6 +16,25 @@ #include <asm/ptrace.h> #include <asm/virt.h> +// Warning, hardcoded register allocation +// This will clobber x1 and x2. +.macro check_override idreg, fld, pass, fail + mrs x1, \idreg\()_el1 + ubfx x1, x1, #\fld, #4 + 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, #4 + ubfx x1, x1, #\fld, #4 + cmp x1, xzr + and x2, x2, x1 + csinv x2, x2, xzr, ne + cbnz x2, \pass + b \fail +.endm + .text .pushsection .hyp.text, "ax" @@ -80,20 +99,7 @@ SYM_CODE_START_LOCAL(__finalise_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 |