[U-Boot-Users] [MIPS] Implement flush_cache()

[Shinya Kuribayashi]

Shinya Kuribayashi wrote:
> Andrew Dyer wrote:
>> looking at how cache_flush() is used (see common/cmd_load.c,
>> common/cmd_elf.c, etc), I believe this loop should also do a cache_op
>> with Hit_Invalidate_I to invalidate the icache.
>>
>> seems like it would be easier to read if the condition was included in
>> the while() statement
> 
> Hm, then is this ok?
<snip>
> @@ -41,6 +52,17 @@ int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
>  
>  void flush_cache(ulong start_addr, ulong size)
>  {
> +	unsigned long lsize = CFG_DCACHE_SIZE;
                              ^^^^^^^^^^^^^^^
Oops, this should have been cache line size.

Patch updated.

P.S. I'll introduce <asm/r4kcache.h> and remove cache_op macro in the
     future. But it takes some time.

================>

[MIPS] Implement flush_cache()

Signed-off-by: Shinya Kuribayashi <skuribay at ruby.dti.ne.jp>
---

 cpu/mips/cpu.c |   22 ++++++++++++++++++++++
 1 files changed, 22 insertions(+), 0 deletions(-)


diff --git a/cpu/mips/cpu.c b/cpu/mips/cpu.c
index 7559ac6..de70c4d 100644
--- a/cpu/mips/cpu.c
+++ b/cpu/mips/cpu.c
@@ -25,6 +25,17 @@
 #include <command.h>
 #include <asm/inca-ip.h>
 #include <asm/mipsregs.h>
+#include <asm/cacheops.h>
+
+#define cache_op(op,addr)						\
+	__asm__ __volatile__(						\
+	"	.set	push					\n"	\
+	"	.set	noreorder				\n"	\
+	"	.set	mips3\n\t				\n"	\
+	"	cache	%0, %1					\n"	\
+	"	.set	pop					\n"	\
+	:								\
+	: "i" (op), "R" (*(unsigned char *)(addr)))
 
 int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 {
@@ -41,6 +52,17 @@ int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 
 void flush_cache(ulong start_addr, ulong size)
 {
+	unsigned long lsize = CFG_CACHELINE_SIZE;
+	unsigned long addr = start_addr & ~(lsize - 1);
+	unsigned long aend = (start_addr + size - 1) & ~(lsize - 1);
+
+	while (1) {
+		cache_op(Hit_Writeback_Inv_D, start_addr);
+		cache_op(Hit_Invalidate_I, start_addr);
+		if (addr == aend)
+			break;
+		addr += lsize;
+	}
 }
 
 void write_one_tlb(int index, u32 pagemask, u32 hi, u32 low0, u32 low1)