diff options
| -rw-r--r-- | Documentation/arch/arm64/booting.rst | 21 | ||||
| -rw-r--r-- | arch/arm64/include/asm/el2_setup.h | 71 |
2 files changed, 89 insertions, 3 deletions
diff --git a/Documentation/arch/arm64/booting.rst b/Documentation/arch/arm64/booting.rst index dee7b6de864f..fbdc4b071755 100644 --- a/Documentation/arch/arm64/booting.rst +++ b/Documentation/arch/arm64/booting.rst @@ -388,6 +388,27 @@ Before jumping into the kernel, the following conditions must be met: - SMCR_EL2.EZT0 (bit 30) must be initialised to 0b1. + For CPUs with the Branch Record Buffer Extension (FEAT_BRBE): + + - If EL3 is present: + + - MDCR_EL3.SBRBE (bits 33:32) must be initialised to 0b01 or 0b11. + + - If the kernel is entered at EL1 and EL2 is present: + + - BRBCR_EL2.CC (bit 3) must be initialised to 0b1. + - BRBCR_EL2.MPRED (bit 4) must be initialised to 0b1. + + - HDFGRTR_EL2.nBRBDATA (bit 61) must be initialised to 0b1. + - HDFGRTR_EL2.nBRBCTL (bit 60) must be initialised to 0b1. + - HDFGRTR_EL2.nBRBIDR (bit 59) must be initialised to 0b1. + + - HDFGWTR_EL2.nBRBDATA (bit 61) must be initialised to 0b1. + - HDFGWTR_EL2.nBRBCTL (bit 60) must be initialised to 0b1. + + - HFGITR_EL2.nBRBIALL (bit 56) must be initialised to 0b1. + - HFGITR_EL2.nBRBINJ (bit 55) must be initialised to 0b1. + For CPUs with the Performance Monitors Extension (FEAT_PMUv3p9): - If EL3 is present: diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h index ba5df0df02a4..de8a57f728c5 100644 --- a/arch/arm64/include/asm/el2_setup.h +++ b/arch/arm64/include/asm/el2_setup.h @@ -189,6 +189,28 @@ .Lskip_set_cptr_\@: .endm +/* + * Configure BRBE to permit recording cycle counts and branch mispredicts. + * + * At any EL, to record cycle counts BRBE requires that both BRBCR_EL2.CC=1 and + * BRBCR_EL1.CC=1. + * + * At any EL, to record branch mispredicts BRBE requires that both + * BRBCR_EL2.MPRED=1 and BRBCR_EL1.MPRED=1. + * + * Set {CC,MPRED} in BRBCR_EL2 in case nVHE mode is used and we are + * executing in EL1. + */ +.macro __init_el2_brbe + mrs x1, id_aa64dfr0_el1 + ubfx x1, x1, #ID_AA64DFR0_EL1_BRBE_SHIFT, #4 + cbz x1, .Lskip_brbe_\@ + + mov_q x0, BRBCR_ELx_CC | BRBCR_ELx_MPRED + msr_s SYS_BRBCR_EL2, x0 +.Lskip_brbe_\@: +.endm + /* Disable any fine grained traps */ .macro __init_el2_fgt mrs x1, id_aa64mmfr0_el1 @@ -196,20 +218,62 @@ cbz x1, .Lskip_fgt_\@ 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_\@ /* Disable PMSNEVFR_EL1 read and write traps */ - orr x0, x0, #(1 << 62) + orr x0, x0, #HDFGRTR_EL2_nPMSNEVFR_EL1_MASK + orr x2, x2, #HDFGWTR_EL2_nPMSNEVFR_EL1_MASK .Lskip_spe_fgt_\@: + mrs x1, id_aa64dfr0_el1 + ubfx x1, x1, #ID_AA64DFR0_EL1_BRBE_SHIFT, #4 + cbz x1, .Lskip_brbe_fgt_\@ + + /* + * Disable read traps for the following registers + * + * [BRBSRC|BRBTGT|RBINF]_EL1 + * [BRBSRCINJ|BRBTGTINJ|BRBINFINJ|BRBTS]_EL1 + */ + orr x0, x0, #HDFGRTR_EL2_nBRBDATA_MASK + + /* + * Disable write traps for the following registers + * + * [BRBSRCINJ|BRBTGTINJ|BRBINFINJ|BRBTS]_EL1 + */ + orr x2, x2, #HDFGWTR_EL2_nBRBDATA_MASK + + /* Disable read and write traps for [BRBCR|BRBFCR]_EL1 */ + orr x0, x0, #HDFGRTR_EL2_nBRBCTL_MASK + orr x2, x2, #HDFGWTR_EL2_nBRBCTL_MASK + + /* Disable read traps for BRBIDR_EL1 */ + orr x0, x0, #HDFGRTR_EL2_nBRBIDR_MASK + +.Lskip_brbe_fgt_\@: .Lset_debug_fgt_\@: msr_s SYS_HDFGRTR_EL2, x0 - msr_s SYS_HDFGWTR_EL2, x0 + msr_s SYS_HDFGWTR_EL2, x2 mov x0, xzr + mov x2, xzr + + mrs x1, id_aa64dfr0_el1 + ubfx x1, x1, #ID_AA64DFR0_EL1_BRBE_SHIFT, #4 + cbz x1, .Lskip_brbe_insn_fgt_\@ + + /* Disable traps for BRBIALL instruction */ + orr x2, x2, #HFGITR_EL2_nBRBIALL_MASK + + /* Disable traps for BRBINJ instruction */ + orr x2, x2, #HFGITR_EL2_nBRBINJ_MASK + +.Lskip_brbe_insn_fgt_\@: mrs x1, id_aa64pfr1_el1 ubfx x1, x1, #ID_AA64PFR1_EL1_SME_SHIFT, #4 cbz x1, .Lskip_sme_fgt_\@ @@ -250,7 +314,7 @@ .Lset_fgt_\@: msr_s SYS_HFGRTR_EL2, x0 msr_s SYS_HFGWTR_EL2, x0 - msr_s SYS_HFGITR_EL2, xzr + msr_s SYS_HFGITR_EL2, x2 mrs x1, id_aa64pfr0_el1 // AMU traps UNDEF without AMU ubfx x1, x1, #ID_AA64PFR0_EL1_AMU_SHIFT, #4 @@ -311,6 +375,7 @@ __init_el2_hcrx __init_el2_timers __init_el2_debug + __init_el2_brbe __init_el2_lor __init_el2_stage2 __init_el2_gicv3 |