[PATCH] IXP425: make cmd_go handle caches correctly
This patch adds icache_invalidate() and dcache_flush() to cpu/ixp/cpu.c.
Also it adds do_go_exec() which is called from do_go(). This private implementation performs cache handling before jumping into the code.
Without this cache handling, you will jump into stale code if you download a program several times.
The patch is against "latest" u-boot git-repository
Please (still) be patient if style of submission or patches are offending.
Signed-off-by: Stefan Althoefer stefan.althoefer@web.de ----
diff -uprN u-boot-orig//cpu/ixp/cpu.c u-boot/cpu/ixp/cpu.c --- u-boot-orig//cpu/ixp/cpu.c 2008-12-02 17:25:31.000000000 +0100 +++ u-boot/cpu/ixp/cpu.c 2008-12-03 11:35:37.000000000 +0100 @@ -171,6 +207,22 @@ int icache_status (void) return (i & 0x1000); }
+void icache_invalidate (void) +{ + register u32 i; + + /* FIXME: Required to check if icache is enabled before we do this? */ + + /* invalidate I-cache (i is ignored)*/ + i = 0; + asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i)); + + /* cpwait */ + asm ("mrc p15,0,%0,c2,c0,0;\ + mov %0,%0;\ + sub pc,pc,#4" : : "r" (i) ); +} + /* we will never enable dcache, because we have to setup MMU first */ void dcache_enable (void) { @@ -187,6 +239,11 @@ int dcache_status (void) return 0; /* always off */ }
+void dcache_flush (void) +{ + return; +} + /* FIXME */ /* void pci_init(void) @@ -195,6 +252,17 @@ void pci_init(void) } */
+/* With IXP (and ARM generally) we need to handle caches to avoid + stale data. */ +unsigned long do_go_exec (ulong (*entry)(int, char *[]), int argc, char *argv[]) +{ + dcache_flush(); + icache_invalidate(); + + return entry (argc, argv); +} + + #ifdef CONFIG_BOOTCOUNT_LIMIT
void bootcount_store (ulong a)