From e6602d4b153b81b49b39c22e70f052f9018687b7 Mon Sep 17 00:00:00 2001 From: Akram Ahmad Date: Mon, 18 Jul 2022 12:27:29 +0100 Subject: [PATCH] fix(errata): workaround for Neoverse-N2 erratum 2376738 Neoverse-N2 erratum 2376738 is a Cat B erratum that applies to revision r0p0 of the CPU. It is fixed in r0p1. The workaround is to set CPUACTLR2_EL1[0] to 1 to force PLDW/PFRM ST to behave like PLD/PRFM LD and not cause invalidations to other PE caches. SDEN can be found here: https://developer.arm.com/documentation/SDEN1982442/latest Signed-off-by: Akram Ahmad Change-Id: I4ad4434f9b7210244e67046d9657d218857dced5 --- docs/design/cpu-specific-build-macros.rst | 4 +++ include/lib/cpus/aarch64/neoverse_n2.h | 1 + lib/cpus/aarch64/neoverse_n2.S | 38 +++++++++++++++++++++++ lib/cpus/cpu-ops.mk | 8 +++++ 4 files changed, 51 insertions(+) diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst index ef4c1a3da..e15c82e10 100644 --- a/docs/design/cpu-specific-build-macros.rst +++ b/docs/design/cpu-specific-build-macros.rst @@ -516,6 +516,10 @@ For Neoverse N2, the following errata build flags are defined : - ``ERRATA_N2_2280757``: This applies errata 2280757 workaround to Neoverse-N2 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. +- ``ERRATA_N2_2376738``: This applies errata 2376738 workaround to Neoverse-N2 + CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in + r0p1. + - ``ERRATA_N2_2388450``: This applies errata 2388450 workaround to Neoverse-N2 CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in r0p1. diff --git a/include/lib/cpus/aarch64/neoverse_n2.h b/include/lib/cpus/aarch64/neoverse_n2.h index 5d41a139e..3ff817c0b 100644 --- a/include/lib/cpus/aarch64/neoverse_n2.h +++ b/include/lib/cpus/aarch64/neoverse_n2.h @@ -37,6 +37,7 @@ * CPU Auxiliary Control register 2 specific definitions. ******************************************************************************/ #define NEOVERSE_N2_CPUACTLR2_EL1 S3_0_C15_C1_1 +#define NEOVERSE_N2_CPUACTLR2_EL1_BIT_0 (ULL(1) << 0) #define NEOVERSE_N2_CPUACTLR2_EL1_BIT_2 (ULL(1) << 2) #define NEOVERSE_N2_CPUACTLR2_EL1_BIT_40 (ULL(1) << 40) diff --git a/lib/cpus/aarch64/neoverse_n2.S b/lib/cpus/aarch64/neoverse_n2.S index fae3be283..a807b636e 100644 --- a/lib/cpus/aarch64/neoverse_n2.S +++ b/lib/cpus/aarch64/neoverse_n2.S @@ -338,6 +338,38 @@ func check_errata_2280757 b cpu_rev_var_ls endfunc check_errata_2280757 + +/* -------------------------------------------------- + * Errata Workaround for Neoverse N2 Erratum 2376738. + * This applies to revision r0p0 of Neoverse N2, + * fixed in r0p1. + * Inputs: + * x0: variant[4:7] and revision[0:3] of current CPU. + * Shall clobber: x0-x1, x17 + * -------------------------------------------------- + */ +func errata_n2_2376738_wa + mov x17, x30 + bl check_errata_2376738 + cbz x0, 1f + + /* Set CPUACTLR2_EL1[0] to 1 to force PLDW/PFRM + * ST to behave like PLD/PFRM LD and not cause + * invalidations to other PE caches. + */ + mrs x1, NEOVERSE_N2_CPUACTLR2_EL1 + orr x1, x1, NEOVERSE_N2_CPUACTLR2_EL1_BIT_0 + msr NEOVERSE_N2_CPUACTLR2_EL1, x1 +1: + ret x17 +endfunc errata_n2_2376738_wa + +func check_errata_2376738 + /* Applies to r0p0, fixed in r0p1 */ + mov x1, 0x00 + b cpu_rev_var_ls +endfunc check_errata_2376738 + /* -------------------------------------------------- * Errata Workaround for Neoverse N2 Erratum 2388450. * This applies to revision r0p0 of Neoverse N2, @@ -447,6 +479,11 @@ func neoverse_n2_reset_func bl errata_n2_2280757_wa #endif +#if ERRATA_N2_2376738 + mov x0, x18 + bl errata_n2_2376738_wa +#endif + #if ERRATA_N2_2388450 mov x0, x18 bl errata_n2_2388450_wa @@ -531,6 +568,7 @@ func neoverse_n2_errata_report report_errata ERRATA_N2_2138958, neoverse_n2, 2138958 report_errata ERRATA_N2_2242400, neoverse_n2, 2242400 report_errata ERRATA_N2_2280757, neoverse_n2, 2280757 + report_errata ERRATA_N2_2376738, neoverse_n2, 2376738 report_errata ERRATA_N2_2388450, neoverse_n2, 2388450 report_errata WORKAROUND_CVE_2022_23960, neoverse_n2, cve_2022_23960 report_errata ERRATA_DSU_2313941, neoverse_n2, dsu_2313941 diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk index 2ed1c6db1..3e5e92a95 100644 --- a/lib/cpus/cpu-ops.mk +++ b/lib/cpus/cpu-ops.mk @@ -572,6 +572,10 @@ ERRATA_N2_2242400 ?=0 # to revision r0p0 of the Neoverse N2 cpu and is still open. ERRATA_N2_2280757 ?=0 +# Flag to apply erratum 2376738 workaround during reset. This erratum applies +# to revision r0p0 of the Neoverse N2 cpu, it is fixed in r0p1. +ERRATA_N2_2376738 ?=0 + # Flag to apply erratum 2388450 workaround during reset. This erratum applies # to revision r0p0 of the Neoverse N2 cpu, it is fixed in r0p1. ERRATA_N2_2388450 ?=0 @@ -1143,6 +1147,10 @@ $(eval $(call add_define,ERRATA_N2_2242400)) $(eval $(call assert_boolean,ERRATA_N2_2280757)) $(eval $(call add_define,ERRATA_N2_2280757)) +# Process ERRATA_N2_2376738 flag +$(eval $(call assert_boolean,ERRATA_N2_2376738)) +$(eval $(call add_define,ERRATA_N2_2376738)) + # Process ERRATA_N2_2388450 flag $(eval $(call assert_boolean,ERRATA_N2_2388450)) $(eval $(call add_define,ERRATA_N2_2388450))