arm64: Cache maintenance routines

The patch adds functionality required for cache maintenance. The AArch64
architecture mandates non-aliasing VIPT or PIPT D-cache and VIPT (may
have aliases) or ASID-tagged VIVT I-cache. Cache maintenance operations
are automatically broadcast in hardware between CPUs.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 48 insertions, 0 deletions

diff --git a/arch/arm64/include/asm/cachetype.h b/arch/arm64/include/asm/cachetype.h
new file mode 100644
index 000000000000..85f5f511352a
--- /dev/null
+++ b/arch/arm64/include/asm/cachetype.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_CACHETYPE_H
+#define __ASM_CACHETYPE_H
+
+#include <asm/cputype.h>
+
+#define CTR_L1IP_SHIFT		14
+#define CTR_L1IP_MASK		3
+
+#define ICACHE_POLICY_RESERVED	0
+#define ICACHE_POLICY_AIVIVT	1
+#define ICACHE_POLICY_VIPT	2
+#define ICACHE_POLICY_PIPT	3
+
+static inline u32 icache_policy(void)
+{
+	return (read_cpuid_cachetype() >> CTR_L1IP_SHIFT) & CTR_L1IP_MASK;
+}
+
+/*
+ * Whilst the D-side always behaves as PIPT on AArch64, aliasing is
+ * permitted in the I-cache.
+ */
+static inline int icache_is_aliasing(void)
+{
+	return icache_policy() != ICACHE_POLICY_PIPT;
+}
+
+static inline int icache_is_aivivt(void)
+{
+	return icache_policy() == ICACHE_POLICY_AIVIVT;
+}
+
+#endif	/* __ASM_CACHETYPE_H */