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| author | Marc Zyngier <maz@kernel.org> | 2022-06-30 17:04:57 +0100 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2022-07-01 15:22:52 +0100 |
| commit | 6ab7661e1d3930edc8462099f047ca2cfdbd343a (patch) | |
| tree | 1caf95e97df3db43a0ede5eecb70ff90abcdd5b1 /arch/arm64/kernel/hyp-stub.S | |
| parent | 6b7ec18c09763f72dcd3d87e194860f9e9db8968 (diff) | |
| download | lwn-6ab7661e1d3930edc8462099f047ca2cfdbd343a.tar.gz lwn-6ab7661e1d3930edc8462099f047ca2cfdbd343a.zip | |
arm64: Expose a __check_override primitive for oddball features
In order to feal with early override of features that are not
classically encoded in a standard ID register with a 4 bit wide
field, add a primitive that takes a sysreg value as an input
(instead of the usual sysreg name) as well as a bit field
width (usually 4).
No functional change.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220630160500.1536744-7-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 | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S index 43c94e7a2c1d..de1ab9843c31 100644 --- a/arch/arm64/kernel/hyp-stub.S +++ b/arch/arm64/kernel/hyp-stub.S @@ -17,17 +17,17 @@ #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 +// 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, #4 - ubfx x1, x1, #\fld, #4 + ubfx x2, x2, #\fld, #\width + ubfx x1, x1, #\fld, #\width cmp x1, xzr and x2, x2, x1 csinv x2, x2, xzr, ne @@ -35,6 +35,11 @@ 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" |