Blackfin: pass RETX to Linux
Make sure we save the value of RETX at power on and then pass it on to the
kernel so that it can nicely debug a "double-fault-caused-a-reset" crash.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/cpu/blackfin/cpu.c b/cpu/blackfin/cpu.c
index 9efd88e..30c214b 100644
--- a/cpu/blackfin/cpu.c
+++ b/cpu/blackfin/cpu.c
@@ -14,11 +14,14 @@
#include <asm/blackfin.h>
#include <asm/cplb.h>
#include <asm/mach-common/bits/core.h>
+#include <asm/mach-common/bits/ebiu.h>
#include <asm/mach-common/bits/trace.h>
#include "cpu.h"
#include "serial.h"
+ulong bfin_poweron_retx;
+
__attribute__ ((__noreturn__))
void cpu_init_f(ulong bootflag, ulong loaded_from_ldr)
{
@@ -48,6 +51,9 @@
bfin_write_EBIU_AMGCTL(CONFIG_EBIU_AMGCTL_VAL);
#endif
+ /* Save RETX so we can pass it while booting Linux */
+ bfin_poweron_retx = bootflag;
+
#ifdef CONFIG_DEBUG_DUMP
/* Turn on hardware trace buffer */
bfin_write_TBUFCTL(TBUFPWR | TBUFEN);
diff --git a/lib_blackfin/boot.c b/lib_blackfin/boot.c
index 47e27de..537be2b 100644
--- a/lib_blackfin/boot.c
+++ b/lib_blackfin/boot.c
@@ -31,6 +31,8 @@
return dest;
}
+extern ulong bfin_poweron_retx;
+
int do_bootm_linux(int flag, int argc, char *argv[], bootm_headers_t *images)
{
int (*appl) (char *cmdline);
@@ -49,7 +51,12 @@
cmdline = make_command_line();
icache_disable();
dcache_disable();
- (*appl) (cmdline);
+ asm __volatile__(
+ "RETX = %[retx];"
+ "CALL (%0);"
+ :
+ : "p"(appl), "q0"(cmdline), [retx] "d"(bfin_poweron_retx)
+ );
/* does not return */
return 1;