nios2: pass command line and initrd to linux in bootm.c

This patch adds bootargs passing to nios2 linux.

The args passing is enabled with,
r4 : 'NIOS' magic
r5 : pointer to initrd start
r6 : pointer to initrd end
r7 : pointer to command line

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>

lib_nios2/bootm.c

@@ -26,21 +26,26 @@
 #include <asm/byteorder.h>
 #include <asm/cache.h>
 
+#define NIOS_MAGIC 0x534f494e /* enable command line and initrd passing */
+
 int do_bootm_linux(int flag, int argc, char *argv[], bootm_headers_t *images)
 {
-	void (*kernel)(void) = (void (*)(void))images->ep;
+	void (*kernel)(int, int, int, char *) = (void *)images->ep;
+	char *commandline = getenv("bootargs");
+	ulong initrd_start = images->rd_start;
+	ulong initrd_end = images->rd_end;
 
 	if ((flag != 0) && (flag != BOOTM_STATE_OS_GO))
 		return 1;
 
 	/* flushes data and instruction caches before calling the kernel */
-	flush_dcache (0,CONFIG_SYS_DCACHE_SIZE);
-	flush_icache (0,CONFIG_SYS_ICACHE_SIZE);
+	disable_interrupts();
+	flush_dcache((ulong)kernel, CONFIG_SYS_DCACHE_SIZE);
+	flush_icache((ulong)kernel, CONFIG_SYS_ICACHE_SIZE);
 
-	/* For now we assume the Microtronix linux ... which only
-	 * needs to be called ;-)
-	 */
-	kernel ();
+	debug("bootargs=%s @ 0x%lx\n", commandline, (ulong)&commandline);
+	debug("initrd=0x%lx-0x%lx\n", (ulong)initrd_start, (ulong)initrd_end);
+	kernel(NIOS_MAGIC, initrd_start, initrd_end, commandline);
 	/* does not return */
 
 	return 1;