riscv: move the AX25-specific implementation of flush_dcache_all
The fence instruction is used to enforce device I/O and memory ordering
constraints in RISC-V. It can not be relied on to directly affect the
data cache on every CPU.
Andes' AX25 does not have a coherence agent. Its fence instruction
flushes the data cache and is used to keep data in the system coherent.
The implementation of flush_dcache_all in lib/cache.c is therefore
specific to the AX25. Move it into the AX25-specific cache.c in
cpu/ax25/.
This also adds a missing new line between flush_dcache_all and
flush_dcache_range in lib/cache.c.
Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/riscv/cpu/ax25/cache.c b/arch/riscv/cpu/ax25/cache.c
index 8d6ae17..228fc55 100644
--- a/arch/riscv/cpu/ax25/cache.c
+++ b/arch/riscv/cpu/ax25/cache.c
@@ -6,6 +6,28 @@
#include <common.h>
+void flush_dcache_all(void)
+{
+ /*
+ * Andes' AX25 does not have a coherence agent. U-Boot must use data
+ * cache flush and invalidate functions to keep data in the system
+ * coherent.
+ * The implementation of the fence instruction in the AX25 flushes the
+ * data cache and is used for this purpose.
+ */
+ asm volatile ("fence" ::: "memory");
+}
+
+void flush_dcache_range(unsigned long start, unsigned long end)
+{
+ flush_dcache_all();
+}
+
+void invalidate_dcache_range(unsigned long start, unsigned long end)
+{
+ flush_dcache_all();
+}
+
void icache_enable(void)
{
#ifndef CONFIG_SYS_ICACHE_OFF