From 1c0eaf0f56d6128af7f0f252855173fcee85d202 Mon Sep 17 00:00:00 2001
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Fri, 30 Jun 2017 17:37:32 -0500
Subject: [PATCH] powerpc/powernv: Tell OPAL about our MMU mode on POWER9
References: bsc#1055117, fate#323286
Patch-mainline: v4.13-rc1
Git-commit: 1c0eaf0f56d6128af7f0f252855173fcee85d202
That will allow OPAL to configure the CPU in an optimal way.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/include/asm/opal-api.h | 9 +++++++++
arch/powerpc/platforms/powernv/opal.c | 19 +++++++++++++++++--
arch/powerpc/platforms/powernv/setup.c | 11 ++++++++++-
3 files changed, 36 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/include/asm/opal-api.h b/arch/powerpc/include/asm/opal-api.h
index ef930ba500f9..3130a73652c7 100644
--- a/arch/powerpc/include/asm/opal-api.h
+++ b/arch/powerpc/include/asm/opal-api.h
@@ -876,6 +876,15 @@ struct OpalIoPhb4ErrorData {
enum {
OPAL_REINIT_CPUS_HILE_BE = (1 << 0),
OPAL_REINIT_CPUS_HILE_LE = (1 << 1),
+
+ /* These two define the base MMU mode of the host on P9
+ *
+ * On P9 Nimbus DD2.0 and Cumlus (and later), KVM can still
+ * create hash guests in "radix" mode with care (full core
+ * switch only).
+ */
+ OPAL_REINIT_CPUS_MMU_HASH = (1 << 2),
+ OPAL_REINIT_CPUS_MMU_RADIX = (1 << 3),
};
typedef struct oppanel_line {
diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index 59684b4af4d1..9b87abb178f0 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -59,6 +59,8 @@ static struct task_struct *kopald_tsk;
void opal_configure_cores(void)
{
+ u64 reinit_flags = 0;
+
/* Do the actual re-init, This will clobber all FPRs, VRs, etc...
*
* It will preserve non volatile GPRs and HSPRG0/1. It will
@@ -66,11 +68,24 @@ void opal_configure_cores(void)
* but it might clobber a bunch.
*/
#ifdef __BIG_ENDIAN__
- opal_reinit_cpus(OPAL_REINIT_CPUS_HILE_BE);
+ reinit_flags |= OPAL_REINIT_CPUS_HILE_BE;
#else
- opal_reinit_cpus(OPAL_REINIT_CPUS_HILE_LE);
+ reinit_flags |= OPAL_REINIT_CPUS_HILE_LE;
#endif
+ /*
+ * POWER9 always support running hash:
+ * ie. Host hash supports hash guests
+ * Host radix supports hash/radix guests
+ */
+ if (cpu_has_feature(CPU_FTR_ARCH_300)) {
+ reinit_flags |= OPAL_REINIT_CPUS_MMU_HASH;
+ if (early_radix_enabled())
+ reinit_flags |= OPAL_REINIT_CPUS_MMU_RADIX;
+ }
+
+ opal_reinit_cpus(reinit_flags);
+
/* Restore some bits */
if (cur_cpu_spec->cpu_restore)
cur_cpu_spec->cpu_restore();
diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 2dc7e5fb86c3..897aa1400eb8 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -225,6 +225,8 @@ static void pnv_kexec_wait_secondaries_down(void)
static void pnv_kexec_cpu_down(int crash_shutdown, int secondary)
{
+ u64 reinit_flags;
+
if (xive_enabled())
xive_kexec_teardown_cpu(secondary);
else
@@ -254,8 +256,15 @@ static void pnv_kexec_cpu_down(int crash_shutdown, int secondary)
* We might be running as little-endian - now that interrupts
* are disabled, reset the HILE bit to big-endian so we don't
* take interrupts in the wrong endian later
+ *
+ * We reinit to enable both radix and hash on P9 to ensure
+ * the mode used by the next kernel is always supported.
*/
- opal_reinit_cpus(OPAL_REINIT_CPUS_HILE_BE);
+ reinit_flags = OPAL_REINIT_CPUS_HILE_BE;
+ if (cpu_has_feature(CPU_FTR_ARCH_300))
+ reinit_flags |= OPAL_REINIT_CPUS_MMU_RADIX |
+ OPAL_REINIT_CPUS_MMU_HASH;
+ opal_reinit_cpus(reinit_flags);
}
}
#endif /* CONFIG_KEXEC_CORE */
--
2.10.2