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| author | lauwal01 <lauren.wehrmeister@arm.com> | 2019-06-24 11:42:02 -0500 |
|---|---|---|
| committer | lauwal01 <lauren.wehrmeister@arm.com> | 2019-07-02 09:16:32 -0500 |
| commit | 335b3c79c79dcfc04e9776ce2e21c3b16aa6febf (patch) | |
| tree | 7af15c666969446e6b24b141048d5edad882101e /lib | |
| parent | 9eceb020d79614cf41d64f6eae4086f3b5390203 (diff) | |
Workaround for Neoverse N1 erratum 1257314
Neoverse N1 erratum 1257314 is a Cat B erratum [1],
present in older revisions of the Neoverse N1 processor core.
The workaround is to set a bit in the implementation defined
CPUACTLR3_EL1 system register, which prevents parallel
execution of divide and square root instructions.
[1] http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.pjdoc-466751330-10325/index.html
Change-Id: I54f0f40ff9043efee40d51e796b92ed85b394cbb
Signed-off-by: Lauren Wehrmeister <lauren.wehrmeister@arm.com>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/cpus/aarch64/neoverse_n1.S | 33 | ||||
| -rw-r--r-- | lib/cpus/cpu-ops.mk | 8 |
2 files changed, 41 insertions, 0 deletions
diff --git a/lib/cpus/aarch64/neoverse_n1.S b/lib/cpus/aarch64/neoverse_n1.S index 0e7b8e8c..19b21a57 100644 --- a/lib/cpus/aarch64/neoverse_n1.S +++ b/lib/cpus/aarch64/neoverse_n1.S @@ -212,6 +212,33 @@ func check_errata_1220197 endfunc check_errata_1220197 /* -------------------------------------------------- + * Errata Workaround for Neoverse N1 Errata #1257314 + * This applies to revision <=r3p0 of Neoverse N1. + * Inputs: + * x0: variant[4:7] and revision[0:3] of current cpu. + * Shall clobber: x0-x17 + * -------------------------------------------------- + */ +func errata_n1_1257314_wa + /* Compare x0 against revision r3p0 */ + mov x17, x30 + bl check_errata_1257314 + cbz x0, 1f + mrs x1, NEOVERSE_N1_CPUACTLR3_EL1 + orr x1, x1, NEOVERSE_N1_CPUACTLR3_EL1_BIT_10 + msr NEOVERSE_N1_CPUACTLR3_EL1, x1 + isb +1: + ret x17 +endfunc errata_n1_1257314_wa + +func check_errata_1257314 + /* Applies to <=r3p0 */ + mov x1, #0x30 + b cpu_rev_var_ls +endfunc check_errata_1257314 + +/* -------------------------------------------------- * Errata Workaround for Neoverse N1 Erratum 1315703. * This applies to revision <= r3p0 of Neoverse N1. * Inputs: @@ -284,6 +311,11 @@ func neoverse_n1_reset_func bl errata_n1_1220197_wa #endif +#if ERRATA_N1_1257314 + mov x0, x18 + bl errata_n1_1257314_wa +#endif + #if ERRATA_N1_1315703 mov x0, x18 bl errata_n1_1315703_wa @@ -351,6 +383,7 @@ func neoverse_n1_errata_report report_errata ERRATA_N1_1165347, neoverse_n1, 1165347 report_errata ERRATA_N1_1207823, neoverse_n1, 1207823 report_errata ERRATA_N1_1220197, neoverse_n1, 1220197 + report_errata ERRATA_N1_1257314, neoverse_n1, 1257314 report_errata ERRATA_N1_1315703, neoverse_n1, 1315703 report_errata ERRATA_DSU_936184, neoverse_n1, dsu_936184 diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk index bb53dad0..c4769d9e 100644 --- a/lib/cpus/cpu-ops.mk +++ b/lib/cpus/cpu-ops.mk @@ -258,6 +258,10 @@ ERRATA_N1_1207823 ?=0 # only to revision <= r2p0 of the Neoverse N1 cpu. ERRATA_N1_1220197 ?=0 +# Flag to apply erratum 1257314 workaround during reset. This erratum applies +# only to revision <= r3p0 of the Neoverse N1 cpu. +ERRATA_N1_1257314 ?=0 + # Flag to apply erratum 1315703 workaround during reset. This erratum applies # to revisions before r3p1 of the Neoverse N1 cpu. ERRATA_N1_1315703 ?=1 @@ -471,6 +475,10 @@ $(eval $(call add_define,ERRATA_N1_1207823)) $(eval $(call assert_boolean,ERRATA_N1_1220197)) $(eval $(call add_define,ERRATA_N1_1220197)) +# Process ERRATA_N1_1257314 flag +$(eval $(call assert_boolean,ERRATA_N1_1257314)) +$(eval $(call add_define,ERRATA_N1_1257314)) + # Process ERRATA_N1_1315703 flag $(eval $(call assert_boolean,ERRATA_N1_1315703)) $(eval $(call add_define,ERRATA_N1_1315703)) |