disable caches before booting an app for Blackfin apps

It isn't generally save to execute applications outside of U-Boot with caches
enabled due to the way the Blackfin processor handles caches (requires
software assistance).  This patch disables caches before booting an ELF or
just booting raw code.  The previous discussion on the patch was that we
wanted to use weaks instead, but that proved to not be feasible when multiple
symbols are involved, which puts us back at the ifdef solution.  I've
minimized the ugliness by moving the setup step outside of the main function.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

diff --git a/common/cmd_boot.c b/common/cmd_boot.c
index e68f16f9da022aa805d5e5f79fec0fa7f9f229d2..9d4f0265981a350402fea7a94b6b8568ade0b694 100644 (file)
--- a/common/cmd_boot.c
+++ b/common/cmd_boot.c
@@ -32,6 +32,23 @@
 DECLARE_GLOBAL_DATA_PTR;
 #endif
 
+static inline void go_setup(int argc, char *argv[])
+{
+#if defined(CONFIG_I386)
+       /*
+        * x86 does not use a dedicated register to pass the pointer
+        * to the global_data
+        */
+       argv[0] = (char *)gd;
+
+#elif defined(CONFIG_BLACKFIN)
+       if (dcache_status ())
+               dcache_disable ();
+       if (icache_status ())
+               icache_disable ();
+#endif
+}
+
 int do_go (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 {
        ulong   addr, rc;
@@ -46,25 +63,20 @@ int do_go (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 
        printf ("## Starting application at 0x%08lX ...\n", addr);
 
+       go_setup(argc, argv);
+
+#if defined(CONFIG_NIOS)
        /*
-        * pass address parameter as argv[0] (aka command name),
-        * and all remaining args
-        */
-#if defined(CONFIG_I386)
-       /*
-        * x86 does not use a dedicated register to pass the pointer
-        * to the global_data
+        * Nios function pointers are address >> 1
         */
-       argv[0] = (char *)gd;
+       addr >>= 1;
 #endif
-#if !defined(CONFIG_NIOS)
-       rc = ((ulong (*)(int, char *[]))addr) (--argc, &argv[1]);
-#else
+
        /*
-        * Nios function pointers are address >> 1
+        * pass address parameter as argv[0] (aka command name),
+        * and all remaining args
         */
-       rc = ((ulong (*)(int, char *[]))(addr>>1)) (--argc, &argv[1]);
-#endif
+       rc = ((ulong (*)(int, char *[]))addr) (--argc, &argv[1]);
        if (rc != 0) rcode = 1;
 
        printf ("## Application terminated, rc = 0x%lX\n", rc);

diff --git a/common/cmd_elf.c b/common/cmd_elf.c
index 2eb745315602afa86b351255844d5d636b4a2a0e..4683554040caaab119b5d4d6bda7799b279e3e66 100644 (file)
--- a/common/cmd_elf.c
+++ b/common/cmd_elf.c
@@ -27,6 +27,21 @@ DECLARE_GLOBAL_DATA_PTR;
 #define MAX(a,b) ((a) > (b) ? (a) : (b))
 #endif
 
+static inline void bootelf_setup(int argc, char *argv[])
+{
+       /*
+        * QNX images require the data cache is disabled.
+        * Data cache is already flushed, so just turn it off.
+        */
+       if (dcache_status ())
+               dcache_disable ();
+
+#ifdef CONFIG_BLACKFIN
+       if (icache_status ())
+               icache_disable ();
+#endif
+}
+
 int valid_elf_image (unsigned long addr);
 unsigned long load_elf_image (unsigned long addr);
 
@@ -53,12 +68,7 @@ int do_bootelf (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 
        printf ("## Starting application at 0x%08lx ...\n", addr);
 
-       /*
-        * QNX images require the data cache is disabled.
-        * Data cache is already flushed, so just turn it off.
-        */
-       if (dcache_status ())
-               dcache_disable ();
+       bootelf_setup(argc, argv);
 
        /*
         * pass address parameter as argv[0] (aka command name),