[v3,7/8] powerpc: Disable DAWR on POWER9 via CPU feature quirk

Message ID 20180327043724.13862-8-mikey@neuling.org
State New
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Series
  • powerpc: Disable DAWR on POWER9
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Commit Message

Michael Neuling March 27, 2018, 4:37 a.m.
This disables the DAWR on all POWER9 CPUs via cpu feature quirk.

Using the DAWR on POWER9 can cause xstops, hence we need to disable
it.

Signed-off-by: Michael Neuling <mikey@neuling.org>
---
 arch/powerpc/kernel/dt_cpu_ftrs.c | 3 +++
 1 file changed, 3 insertions(+)

Patch

diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c b/arch/powerpc/kernel/dt_cpu_ftrs.c
index 945e2c29ad..941a5fbd8d 100644
--- a/arch/powerpc/kernel/dt_cpu_ftrs.c
+++ b/arch/powerpc/kernel/dt_cpu_ftrs.c
@@ -709,6 +709,9 @@  static __init void cpufeatures_cpu_quirks(void)
 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD1;
 	else if ((version & 0xffffefff) == 0x004e0201)
 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
+
+	if ((version & 0xffff0000) == 0x004e0000)
+		cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
 }
 
 static void __init cpufeatures_setup_finished(void)