Djam/arm-trusted-firmware
1
0
Fork 0
mirror of https://github.com/ARM-software/arm-trusted-firmware.git synced 2025-04-18 18:44:22 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Workaround for Neoverse N1 erratum 1257314

Browse source 
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>
This commit is contained in:
lauwal01 2019-06-24 11:42:02 -05:00
parent 9eceb020d7
commit 335b3c79c7
4 changed files with 47 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
docs/design/cpu-specific-build-macros.rst
View file

@ -243,6 +243,9 @@ For Neoverse N1, the following errata build flags are defined :
- ``ERRATA_N1_1220197``: This applies errata 1220197 workaround to Neoverse-N1
CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
- ``ERRATA_N1_1257314``: This applies errata 1257314 workaround to Neoverse-N1
CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
- ``ERRATA_N1_1315703``: This applies errata 1315703 workaround to Neoverse-N1
CPU. This needs to be enabled only for revision <= r3p0 of the CPU.

3
include/lib/cpus/aarch64/neoverse_n1.h
View file

@ -48,6 +48,9 @@
#define NEOVERSE_N1_CPUACTLR2_EL1_BIT_16 (ULL(1) << 16)
#define NEOVERSE_N1_CPUACTLR2_EL1_BIT_59 (ULL(1) << 59)
#define NEOVERSE_N1_CPUACTLR3_EL1 S3_0_C15_C1_2
#define NEOVERSE_N1_CPUACTLR3_EL1_BIT_10 (ULL(1) << 10)
/* Instruction patching registers */
#define CPUPSELR_EL3 S3_6_C15_C8_0

33
lib/cpus/aarch64/neoverse_n1.S
View file

@ -211,6 +211,33 @@ func check_errata_1220197
b cpu_rev_var_ls
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.
@ -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

8
lib/cpus/cpu-ops.mk
View file

@ -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))