On 08/14/2015 11:28 AM, Robert Richter wrote:
From: Robert Richter <[email protected]>
This patch implements Cavium ThunderX erratum 23154.
The gicv3 of ThunderX requires a modified version for reading the IAR
status to ensure data synchronization. Since this is in the fast-path
and called with each interrupt, runtime patching is used using jump
label patching for smallest overhead (no-op). This is the same
technique as used for tracepoints.
v4:
* simplify code to only use cpus_have_cap() in gicv3_enable_quirks()
v3:
* fix erratum to be dependend from midr
* use arm64 errata framework
v2:
* implement code in a single asm() to keep instruction sequence
* added comment to the code that explains the erratum
* apply workaround also if running as guest, thus check MIDR
Signed-off-by: Robert Richter <[email protected]>
---
arch/arm64/Kconfig | 11 ++++++++++
arch/arm64/include/asm/cpufeature.h | 3 ++-
arch/arm64/include/asm/cputype.h | 18 +++++++++-------
arch/arm64/kernel/cpu_errata.c | 9 ++++++++
drivers/irqchip/irq-gic-v3.c | 42 ++++++++++++++++++++++++++++++++++++-
5 files changed, 74 insertions(+), 9 deletions(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 0f6edb14b7e4..4f866a4c6536 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -417,6 +417,17 @@ config ARM64_ERRATUM_845719
If unsure, say Y.
+config CAVIUM_ERRATUM_23154
+ bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
+ depends on ARCH_THUNDER
None of the other errata depend on a specific ARCH_*. I think we should
remove this 'depends on', so that a generic kernel can be configured to
work on Thunder without having to first select ARCH_THUNDER.
David Daney
+ default y
+ help
+ The gicv3 of ThunderX requires a modified version for
+ reading the IAR status to ensure data synchronization
+ (access to icc_iar1_el1 is not sync'ed before and after).
+
+ If unsure, say Y.
+
endmenu
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
