6.12-stable review patch. If anyone has any objections, please let me know.
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From: Anshuman Khandual anshuman.khandual@arm.com
commit 858c7bfcb35e1100b58bb63c9f562d86e09418d9 upstream.
FEAT_PMUv3p9 registers such as PMICNTR_EL0, PMICFILTR_EL0, and PMUACR_EL1 access from EL1 requires appropriate EL2 fine grained trap configuration via FEAT_FGT2 based trap control registers HDFGRTR2_EL2 and HDFGWTR2_EL2. Otherwise such register accesses will result in traps into EL2.
Add a new helper __init_el2_fgt2() which initializes FEAT_FGT2 based fine grained trap control registers HDFGRTR2_EL2 and HDFGWTR2_EL2 (setting the bits nPMICNTR_EL0, nPMICFILTR_EL0 and nPMUACR_EL1) to enable access into PMICNTR_EL0, PMICFILTR_EL0, and PMUACR_EL1 registers.
Also update booting.rst with SCR_EL3.FGTEn2 requirement for all FEAT_FGT2 based registers to be accessible in EL2.
Cc: Will Deacon will@kernel.org Cc: Mark Rutland mark.rutland@arm.com Cc: Rob Herring robh@kernel.org Cc: Jonathan Corbet corbet@lwn.net Cc: Marc Zyngier maz@kernel.org Cc: Oliver Upton oliver.upton@linux.dev Cc: linux-arm-kernel@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: kvmarm@lists.linux.dev Fixes: 0bbff9ed8165 ("perf/arm_pmuv3: Add PMUv3.9 per counter EL0 access control") Fixes: d8226d8cfbaf ("perf: arm_pmuv3: Add support for Armv9.4 PMU instruction counter") Tested-by: Rob Herring (Arm) robh@kernel.org Reviewed-by: Rob Herring (Arm) robh@kernel.org Signed-off-by: Anshuman Khandual anshuman.khandual@arm.com Link: https://lore.kernel.org/r/20250227035119.2025171-1-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Anshuman Khandual anshuman.khandual@arm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- Documentation/arch/arm64/booting.rst | 22 ++++++++++++++++++++++ arch/arm64/include/asm/el2_setup.h | 25 +++++++++++++++++++++++++ arch/arm64/tools/sysreg | 1 + 3 files changed, 48 insertions(+)
--- a/Documentation/arch/arm64/booting.rst +++ b/Documentation/arch/arm64/booting.rst @@ -285,6 +285,12 @@ Before jumping into the kernel, the foll
- SCR_EL3.FGTEn (bit 27) must be initialised to 0b1.
+ For CPUs with the Fine Grained Traps 2 (FEAT_FGT2) extension present: + + - If EL3 is present and the kernel is entered at EL2: + + - SCR_EL3.FGTEn2 (bit 59) must be initialised to 0b1. + For CPUs with support for HCRX_EL2 (FEAT_HCX) present:
- If EL3 is present and the kernel is entered at EL2: @@ -379,6 +385,22 @@ Before jumping into the kernel, the foll
- SMCR_EL2.EZT0 (bit 30) must be initialised to 0b1.
+ For CPUs with the Performance Monitors Extension (FEAT_PMUv3p9): + + - If EL3 is present: + + - MDCR_EL3.EnPM2 (bit 7) must be initialised to 0b1. + + - If the kernel is entered at EL1 and EL2 is present: + + - HDFGRTR2_EL2.nPMICNTR_EL0 (bit 2) must be initialised to 0b1. + - HDFGRTR2_EL2.nPMICFILTR_EL0 (bit 3) must be initialised to 0b1. + - HDFGRTR2_EL2.nPMUACR_EL1 (bit 4) must be initialised to 0b1. + + - HDFGWTR2_EL2.nPMICNTR_EL0 (bit 2) must be initialised to 0b1. + - HDFGWTR2_EL2.nPMICFILTR_EL0 (bit 3) must be initialised to 0b1. + - HDFGWTR2_EL2.nPMUACR_EL1 (bit 4) must be initialised to 0b1. + For CPUs with Memory Copy and Memory Set instructions (FEAT_MOPS):
- If the kernel is entered at EL1 and EL2 is present: --- a/arch/arm64/include/asm/el2_setup.h +++ b/arch/arm64/include/asm/el2_setup.h @@ -215,6 +215,30 @@ .Lskip_fgt_@: .endm
+.macro __init_el2_fgt2 + mrs x1, id_aa64mmfr0_el1 + ubfx x1, x1, #ID_AA64MMFR0_EL1_FGT_SHIFT, #4 + cmp x1, #ID_AA64MMFR0_EL1_FGT_FGT2 + b.lt .Lskip_fgt2_@ + + mov x0, xzr + mrs x1, id_aa64dfr0_el1 + ubfx x1, x1, #ID_AA64DFR0_EL1_PMUVer_SHIFT, #4 + cmp x1, #ID_AA64DFR0_EL1_PMUVer_V3P9 + b.lt .Lskip_pmuv3p9_@ + + orr x0, x0, #HDFGRTR2_EL2_nPMICNTR_EL0 + orr x0, x0, #HDFGRTR2_EL2_nPMICFILTR_EL0 + orr x0, x0, #HDFGRTR2_EL2_nPMUACR_EL1 +.Lskip_pmuv3p9_@: + msr_s SYS_HDFGRTR2_EL2, x0 + msr_s SYS_HDFGWTR2_EL2, x0 + msr_s SYS_HFGRTR2_EL2, xzr + msr_s SYS_HFGWTR2_EL2, xzr + msr_s SYS_HFGITR2_EL2, xzr +.Lskip_fgt2_@: +.endm + .macro __init_el2_nvhe_prepare_eret mov x0, #INIT_PSTATE_EL1 msr spsr_el2, x0 @@ -240,6 +264,7 @@ __init_el2_nvhe_idregs __init_el2_cptr __init_el2_fgt + __init_el2_fgt2 .endm
#ifndef __KVM_NVHE_HYPERVISOR__ --- a/arch/arm64/tools/sysreg +++ b/arch/arm64/tools/sysreg @@ -1238,6 +1238,7 @@ UnsignedEnum 11:8 PMUVer 0b0110 V3P5 0b0111 V3P7 0b1000 V3P8 + 0b1001 V3P9 0b1111 IMP_DEF EndEnum UnsignedEnum 7:4 TraceVer