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authorWaldemar Brodkorb <wbx@openadk.org>2020-08-17 15:44:58 +0200
committerWaldemar Brodkorb <wbx@openadk.org>2020-08-17 15:46:44 +0200
commit8b1f6b2e08ed3c15484c2ca0c3f0a45125c559c1 (patch)
tree763fbe923f69a3b57565ef62948b233d7269fa68 /libc/sysdeps/linux/riscv64/cache.c
parent00972c02c2b6e0a95d5def4a71bdfb188e091782 (diff)
riscv64: add __riscv_flush_icache
Always use the systemcall as uClibc-ng has no vdso support. Tested with libffi and python in qemu-system-riscv64.
Diffstat (limited to 'libc/sysdeps/linux/riscv64/cache.c')
-rw-r--r--libc/sysdeps/linux/riscv64/cache.c51
1 files changed, 51 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/riscv64/cache.c b/libc/sysdeps/linux/riscv64/cache.c
new file mode 100644
index 000000000..216b333f3
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/cache.c
@@ -0,0 +1,51 @@
+/* RISC-V instruction cache flushing VDSO calls
+ Copyright (C) 2017-2020 Free Software Foundation, Inc.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <stdlib.h>
+#include <atomic.h>
+#include <sys/syscall.h>
+
+typedef int (*func_type) (void *, void *, unsigned long int);
+
+static int
+__riscv_flush_icache_syscall (void *start, void *end, unsigned long int flags)
+{
+ return INLINE_SYSCALL (riscv_flush_icache, 3, start, end, flags);
+}
+
+static func_type
+__lookup_riscv_flush_icache (void)
+{
+ /* always call the system call directly.*/
+ return &__riscv_flush_icache_syscall;
+}
+
+int
+__riscv_flush_icache (void *start, void *end, unsigned long int flags)
+{
+ static volatile func_type cached_func;
+
+ func_type func = atomic_load_relaxed (&cached_func);
+
+ if (!func)
+ {
+ func = __lookup_riscv_flush_icache ();
+ atomic_store_relaxed (&cached_func, func);
+ }
+
+ return func (start, end, flags);
+}