[PATCH v7 05/12] arm64/boot: Factor out a macro to check SPE version

From: James Clark
Date: Thu Aug 14 2025 - 05:29:59 EST


We check the version of SPE twice, and we'll add one more check in the
next commit so factor out a macro to do this. Change the #3 magic number
to the actual SPE version define (V1p2) to make it more readable.

No functional changes intended.

Tested-by: Leo Yan <leo.yan@xxxxxxx>
Signed-off-by: James Clark <james.clark@xxxxxxxxxx>
---
arch/arm64/include/asm/el2_setup.h | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h
index 46033027510c..3a4ca7f9acfb 100644
--- a/arch/arm64/include/asm/el2_setup.h
+++ b/arch/arm64/include/asm/el2_setup.h
@@ -103,8 +103,7 @@
csel x2, xzr, x0, eq // all PMU counters from EL1

/* Statistical profiling */
- ubfx x0, x1, #ID_AA64DFR0_EL1_PMSVer_SHIFT, #4
- cbz x0, .Lskip_spe_\@ // Skip if SPE not present
+ __spe_vers_imp .Lskip_spe_\@, ID_AA64DFR0_EL1_PMSVer_IMP, x0 // Skip if SPE not present

mrs_s x0, SYS_PMBIDR_EL1 // If SPE available at EL2,
and x0, x0, #(1 << PMBIDR_EL1_P_SHIFT)
@@ -255,6 +254,14 @@
.Lskip_brbe_\@:
.endm

+/* Branch to skip_label if SPE version is less than given version */
+.macro __spe_vers_imp skip_label, version, tmp
+ mrs \tmp, id_aa64dfr0_el1
+ ubfx \tmp, \tmp, #ID_AA64DFR0_EL1_PMSVer_SHIFT, #4
+ cmp \tmp, \version
+ b.lt \skip_label
+.endm
+
/* Disable any fine grained traps */
.macro __init_el2_fgt
mrs x1, id_aa64mmfr0_el1
@@ -263,10 +270,8 @@

mov x0, xzr
mov x2, xzr
- mrs x1, id_aa64dfr0_el1
- ubfx x1, x1, #ID_AA64DFR0_EL1_PMSVer_SHIFT, #4
- cmp x1, #3
- b.lt .Lskip_spe_fgt_\@
+ /* If SPEv1p2 is implemented, */
+ __spe_vers_imp .Lskip_spe_fgt_\@, #ID_AA64DFR0_EL1_PMSVer_V1P2, x1
/* Disable PMSNEVFR_EL1 read and write traps */
orr x0, x0, #HDFGRTR_EL2_nPMSNEVFR_EL1_MASK
orr x2, x2, #HDFGWTR_EL2_nPMSNEVFR_EL1_MASK

--
2.34.1