[U-Boot] [PATCH] nios2: fix out of reach case for do_reset

[Thomas Chou <thomas@wytron.com.tw>]

The "Nios II Processor Reference Handbook" said,
"call can transfer execution anywhere within the 256 MByte range
determined by PC31..28. The Nios II GNU linker does not automatically
handle cases in which the address is out of this range."

So we have to use registered "callr" instruction to do the job.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
---
 arch/nios2/cpu/cpu.c |   14 ++++++++------
 1 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/arch/nios2/cpu/cpu.c b/arch/nios2/cpu/cpu.c
index 6379534..d9c3003 100644
--- a/arch/nios2/cpu/cpu.c
+++ b/arch/nios2/cpu/cpu.c
@@ -40,11 +40,13 @@ int checkcpu (void)
 	return (0);
 }
 
-
-int do_reset (void)
+int do_reset(void)
 {
-	void (*rst)(void) = (void(*)(void))CONFIG_SYS_RESET_ADDR;
-	disable_interrupts ();
-	rst();
-	return(0);
+	disable_interrupts();
+	__asm__ __volatile__ (
+	"callr	%0"
+	:
+	: "r" (CONFIG_SYS_RESET_ADDR)
+	);
+	return 0;
 }
-- 
1.7.2.1