[PATCH v6 16/18] ACPI / APEI: Split fixmap pages for arm64 NMI-like notifications

[James Morse <james.morse@arm.com>]

Now that ghes notification helpers provide the fixmap slots and
take the lock themselves we can support multiple NMI-like
notifications on arm64.

These should be named after their notification method. x86's
NOTIFY_NMI already is, move it to live with the ghes_nmi list.
Change the SEA fixmap entry to be called FIX_APEI_GHES_SEA.

Future patches can add support for FIX_APEI_GHES_SEI and
FIX_APEI_GHES_SDEI_{NORMAL,CRITICAL}.

Signed-off-by: James Morse <james.morse@arm.com>

---
Changes since v3:
 * idx/lock are now in a separate struct.
 * Add to the comment above ghes_fixmap_lock_irq so that it makes more
   sense in isolation.
---
 arch/arm64/include/asm/fixmap.h | 4 +++-
 drivers/acpi/apei/ghes.c        | 6 +++---
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/include/asm/fixmap.h b/arch/arm64/include/asm/fixmap.h
index ec1e6d6fa14c..c3974517c2cb 100644
--- a/arch/arm64/include/asm/fixmap.h
+++ b/arch/arm64/include/asm/fixmap.h
@@ -55,7 +55,9 @@ enum fixed_addresses {
 #ifdef CONFIG_ACPI_APEI_GHES
 	/* Used for GHES mapping from assorted contexts */
 	FIX_APEI_GHES_IRQ,
-	FIX_APEI_GHES_NMI,
+#ifdef CONFIG_ACPI_APEI_SEA
+	FIX_APEI_GHES_SEA,
+#endif
 #endif /* CONFIG_ACPI_APEI_GHES */
 
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index a0c10b60ad44..463c8e6d1bb5 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -994,7 +994,7 @@ int ghes_notify_sea(void)
 	int rv;
 
 	raw_spin_lock(&ghes_notify_lock_sea);
-	rv = ghes_estatus_queue_notified(&ghes_sea, FIX_APEI_GHES_NMI);
+	rv = ghes_estatus_queue_notified(&ghes_sea, FIX_APEI_GHES_SEA);
 	raw_spin_unlock(&ghes_notify_lock_sea);
 
 	return rv;
@@ -1025,8 +1025,8 @@ static inline void ghes_sea_remove(struct ghes *ghes) { }
 
 #ifdef CONFIG_HAVE_ACPI_APEI_NMI
 /*
- * NMI may be triggered on any CPU, so ghes_in_nmi is used for
- * having only one concurrent reader.
+ * NOTIFY_NMI may be triggered on any CPU, so ghes_in_nmi is
+ * used for having only one concurrent reader.
  */
 static atomic_t ghes_in_nmi = ATOMIC_INIT(0);
 
-- 
2.19.0