powerpc: Disable DAWR on POWER9 via CPU feature quirk

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>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c b/arch/powerpc/kernel/dt_cpu_ftrs.c
index 0a0c601c6ade59aaf743a9bd7cf6a760c9860932..0af2c5dc5162a7254fc029707c76d713ae6ad719 100644 (file)
--- a/arch/powerpc/kernel/dt_cpu_ftrs.c
+++ b/arch/powerpc/kernel/dt_cpu_ftrs.c
@@ -713,6 +713,9 @@ static __init void cpufeatures_cpu_quirks(void)
        else if ((version & 0xffffefff) == 0x004e0202)
                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST |
                        CPU_FTR_P9_TM_XER_SO_BUG;
+
+       if ((version & 0xffff0000) == 0x004e0000)
+               cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
 }
 
 static void __init cpufeatures_setup_finished(void)