On 01/09/2025 11:19 am, Leo Yan wrote:
On Thu, Aug 14, 2025 at 10:25:28AM +0100, James Clark wrote:
[...]
diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h
index 3a4ca7f9acfb..a0361ddcdca4 100644
--- a/arch/arm64/include/asm/el2_setup.h
+++ b/arch/arm64/include/asm/el2_setup.h
@@ -392,6 +392,17 @@
orr x0, x0, #HDFGRTR2_EL2_nPMICFILTR_EL0
orr x0, x0, #HDFGRTR2_EL2_nPMUACR_EL1
.Lskip_pmuv3p9_\@:
+ /* If SPE is implemented, */
+ __spe_vers_imp .Lskip_spefds_\@, ID_AA64DFR0_EL1_PMSVer_IMP, x1
+ /* we can read PMSIDR and */
+ mrs_s x1, SYS_PMSIDR_EL1
+ and x1, x1, #PMSIDR_EL1_FDS
+ /* if FEAT_SPE_FDS is implemented, */
+ cbz x1, .Lskip_spefds_\@
+ /* disable traps to PMSDSFR. */
Nitpick: the comment is a bit ambiguous for me. Would it be better to
say "disable traps to EL2" or "set the PMSDSFR bit to disable trapping" ?
Otherwise, LGTM:
Reviewed-by: Leo Yan <leo.yan@xxxxxxx>
The bit we're setting is actually called nPMSDSFR_EL1, but I can change
it to:
/* disable traps of PMSDSFR to EL2 */
+ orr x0, x0, #HDFGRTR2_EL2_nPMSDSFR_EL1
+
+.Lskip_spefds_\@:
msr_s SYS_HDFGRTR2_EL2, x0
msr_s SYS_HDFGWTR2_EL2, x0
msr_s SYS_HFGRTR2_EL2, xzr
--
2.34.1
