Date: Tue, 13 Sep 2016 14:14:40 +0000 (UTC) From: Andrew Turner <andrew@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Subject: svn commit: r305768 - stable/11/sys/arm64/arm64 Message-ID: <201609131414.u8DEEeZc095482@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: andrew Date: Tue Sep 13 14:14:39 2016 New Revision: 305768 URL: https://svnweb.freebsd.org/changeset/base/305768 Log: MFC 305767: Add a warning about a known erratum we have observed on ThunderX pass 1.1. As this is evaluation hardware with only a few users, and there is a lack of information add a warning when booting on this hardware. Modified: stable/11/sys/arm64/arm64/identcpu.c Directory Properties: stable/11/ (props changed) Modified: stable/11/sys/arm64/arm64/identcpu.c ============================================================================== --- stable/11/sys/arm64/arm64/identcpu.c Tue Sep 13 14:10:49 2016 (r305767) +++ stable/11/sys/arm64/arm64/identcpu.c Tue Sep 13 14:14:39 2016 (r305768) @@ -179,6 +179,28 @@ print_cpu_features(u_int cpu) } printf("\n"); + /* + * There is a hardware errata where, if one CPU is performing a TLB + * invalidation while another is performing a store-exclusive the + * store-exclusive may return the wrong status. A workaround seems + * to be to use an IPI to invalidate on each CPU, however given the + * limited number of affected units (pass 1.1 is the evaluation + * hardware revision), and the lack of information from Cavium + * this has not been implemented. + * + * At the time of writing this the only information is from: + * https://lkml.org/lkml/2016/8/4/722 + */ + /* + * XXX: CPU_MATCH_ERRATA_CAVIUM_THUNDER_1_1 on it's own also + * triggers on pass 2.0+. + */ + if (cpu == 0 && CPU_VAR(PCPU_GET(midr)) == 0 && + CPU_MATCH_ERRATA_CAVIUM_THUNDER_1_1) + printf("WARNING: ThunderX Pass 1.1 detected.\nThis has known " + "hardware bugs that may cause the incorrect operation of " + "atomic operations.\n"); + if (cpu != 0 && cpu_print_regs == 0) return;
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201609131414.u8DEEeZc095482>