diff options
| author | Xi Ruoyao <xry111@xry111.site> | 2025-06-02 12:33:21 +0800 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2025-06-02 13:49:09 +0100 |
| commit | 10f885d63a0efd50b0d22bf27eb3cf727838e99e (patch) | |
| tree | 4acda9bf556f9ef19536ff50d672d5cef4ecb1fe /arch/arm64/include | |
| parent | 4b634918384c0f84c33aeb4dd9fd4c38e7be5ccb (diff) | |
arm64: Add override for MPAM
As the message of the commit 09e6b306f3ba ("arm64: cpufeature: discover
CPU support for MPAM") already states, if a buggy firmware fails to
either enable MPAM or emulate the trap as if it were disabled, the
kernel will just fail to boot. While upgrading the firmware should be
the best solution, we have some hardware of which the vendor have made
no response 2 months after we requested a firmware update. Allow
overriding it so our devices don't become some e-waste.
Cc: James Morse <james.morse@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Cc: Mingcong Bai <jeffbai@aosc.io>
Cc: Shaopeng Tan <tan.shaopeng@fujitsu.com>
Cc: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250602043723.216338-1-xry111@xry111.site
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/include')
| -rw-r--r-- | arch/arm64/include/asm/el2_setup.h | 24 |
1 files changed, 10 insertions, 14 deletions
diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h index 30f57b0334a3..af7807f11df4 100644 --- a/arch/arm64/include/asm/el2_setup.h +++ b/arch/arm64/include/asm/el2_setup.h @@ -298,19 +298,6 @@ .Lskip_gcs_\@: .endm -.macro __init_el2_mpam - /* Memory Partitioning And Monitoring: disable EL2 traps */ - mrs x1, id_aa64pfr0_el1 - ubfx x0, x1, #ID_AA64PFR0_EL1_MPAM_SHIFT, #4 - cbz x0, .Lskip_mpam_\@ // skip if no MPAM - msr_s SYS_MPAM2_EL2, xzr // use the default partition - // and disable lower traps - mrs_s x0, SYS_MPAMIDR_EL1 - tbz x0, #MPAMIDR_EL1_HAS_HCR_SHIFT, .Lskip_mpam_\@ // skip if no MPAMHCR reg - msr_s SYS_MPAMHCR_EL2, xzr // clear TRAP_MPAMIDR_EL1 -> EL2 -.Lskip_mpam_\@: -.endm - /** * Initialize EL2 registers to sane values. This should be called early on all * cores that were booted in EL2. Note that everything gets initialised as @@ -328,7 +315,6 @@ __init_el2_stage2 __init_el2_gicv3 __init_el2_hstr - __init_el2_mpam __init_el2_nvhe_idregs __init_el2_cptr __init_el2_fgt @@ -375,6 +361,16 @@ #endif .macro finalise_el2_state + check_override id_aa64pfr0, ID_AA64PFR0_EL1_MPAM_SHIFT, .Linit_mpam_\@, .Lskip_mpam_\@, x1, x2 + +.Linit_mpam_\@: + msr_s SYS_MPAM2_EL2, xzr // use the default partition + // and disable lower traps + mrs_s x0, SYS_MPAMIDR_EL1 + tbz x0, #MPAMIDR_EL1_HAS_HCR_SHIFT, .Lskip_mpam_\@ // skip if no MPAMHCR reg + msr_s SYS_MPAMHCR_EL2, xzr // clear TRAP_MPAMIDR_EL1 -> EL2 + +.Lskip_mpam_\@: check_override id_aa64pfr0, ID_AA64PFR0_EL1_SVE_SHIFT, .Linit_sve_\@, .Lskip_sve_\@, x1, x2 .Linit_sve_\@: /* SVE register access */ |