@@ -18,6 +18,9 @@ extern void (*udbg_putc)(char c);
extern void (*udbg_flush)(void);
extern int (*udbg_getc)(void);
extern int (*udbg_getc_poll)(void);
+#ifdef CONFIG_PPC_EARLY_DEBUG
+extern void (*udbg_early_remap)(void);
+#endif
extern void udbg_puts(const char *s);
extern int udbg_write(const char *s, int n);
@@ -21,6 +21,9 @@ void (*udbg_putc)(char c);
void (*udbg_flush)(void);
int (*udbg_getc)(void);
int (*udbg_getc_poll)(void);
+#ifdef CONFIG_PPC_EARLY_DEBUG
+void (*udbg_early_remap)(void);
+#endif
/*
* Early debugging facilities. You can enable _one_ of these via .config,
@@ -43,6 +43,7 @@
#include <asm/tlb.h>
#include <asm/sections.h>
#include <asm/system.h>
+#include <asm/udbg.h>
#include "mmu_decl.h"
@@ -180,6 +181,15 @@ void __init MMU_init(void)
#ifdef CONFIG_BOOTX_TEXT
btext_unmap();
#endif
+#ifdef CONFIG_PPC_EARLY_DEBUG
+ /*
+ * This hook can be used by a low level early udbg driver to either
+ * provide a new valid I/O mapping to be used after MMU_init
+ * or just to safely disable actual udbg I/O from now on.
+ */
+ if (udbg_early_remap)
+ udbg_early_remap();
+#endif
}
/* This is only called until mem_init is done. */
The udbg facility provides an early debug extension that can be enabled using CONFIG_PPC_EARLY_DEBUG. In some cases, this early debugging facility cannot be used after MMU_init runs (and the MMU is loaded and enabled with the definitive mappings) because the early mappings are not valid anymore. This patch provides a udbg hook called udbg_early_remap that gets called at the end of MMU_init and can be used by a low level udbg driver to accomplish several goals, like: - extending the early debugging life by configuring and using a new valid I/O mapping - safely disabling the early debugging Signed-off-by: Albert Herranz <albert_herranz@yahoo.es> --- arch/powerpc/include/asm/udbg.h | 3 +++ arch/powerpc/kernel/udbg.c | 3 +++ arch/powerpc/mm/init_32.c | 10 ++++++++++ 3 files changed, 16 insertions(+), 0 deletions(-)