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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/riscv/include/asm/clint.h
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/riscv/include/asm/clint.h')
-rw-r--r--arch/riscv/include/asm/clint.h26
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/clint.h b/arch/riscv/include/asm/clint.h
new file mode 100644
index 000000000..0789fd37b
--- /dev/null
+++ b/arch/riscv/include/asm/clint.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 Google, Inc
+ */
+
+#ifndef _ASM_RISCV_CLINT_H
+#define _ASM_RISCV_CLINT_H
+
+#include <linux/types.h>
+#include <asm/mmio.h>
+
+#ifdef CONFIG_RISCV_M_MODE
+/*
+ * This lives in the CLINT driver, but is accessed directly by timex.h to avoid
+ * any overhead when accessing the MMIO timer.
+ *
+ * The ISA defines mtime as a 64-bit memory-mapped register that increments at
+ * a constant frequency, but it doesn't define some other constraints we depend
+ * on (most notably ordering constraints, but also some simpler stuff like the
+ * memory layout). Thus, this is called "clint_time_val" instead of something
+ * like "riscv_mtime", to signify that these non-ISA assumptions must hold.
+ */
+extern u64 __iomem *clint_time_val;
+#endif
+
+#endif