spl: make image arg or fdt blob address reconfigurable

At present fdt blob or argument address being passed to kernel is fixed at
compile time using macro CONFIG_SYS_SPL_ARGS_ADDR. FDT blob from
different media like nand, nor flash are copied to the address pointed
by the macro.
The problem is, it makes args/fdt blob compulsory to copy which is not required
in cases like for NOR Flash. This patch removes this limitation.

Signed-off-by: Vikas Manocha <vikas.manocha@st.com>

arch/arm/lib/spl.c

@@ -44,22 +44,21 @@ void __weak board_init_f(ulong dummy)
 /*
  * This function jumps to an image with argument. Normally an FDT or ATAGS
  * image.
- * arg: Pointer to paramter image in RAM
  */
 #ifdef CONFIG_SPL_OS_BOOT
-void __noreturn jump_to_image_linux(struct spl_image_info *spl_image, void *arg)
+void __noreturn jump_to_image_linux(struct spl_image_info *spl_image)
 {
 	unsigned long machid = 0xffffffff;
 #ifdef CONFIG_MACH_TYPE
 	machid = CONFIG_MACH_TYPE;
 #endif
 
-	debug("Entering kernel arg pointer: 0x%p\n", arg);
+	debug("Entering kernel arg pointer: 0x%p\n", spl_image->arg);
 	typedef void (*image_entry_arg_t)(int, int, void *)
 		__attribute__ ((noreturn));
 	image_entry_arg_t image_entry =
 		(image_entry_arg_t)(uintptr_t) spl_image->entry_point;
 	cleanup_before_linux();
-	image_entry(0, machid, arg);
+	image_entry(0, machid, spl_image->arg);
 }
 #endif

arch/microblaze/cpu/spl.c

@@ -29,15 +29,15 @@ void spl_board_init(void)
 }
 
 #ifdef CONFIG_SPL_OS_BOOT
-void __noreturn jump_to_image_linux(struct spl_image_info *spl_image, void *arg)
+void __noreturn jump_to_image_linux(struct spl_image_info *spl_image)
 {
-	debug("Entering kernel arg pointer: 0x%p\n", arg);
+	debug("Entering kernel arg pointer: 0x%p\n", spl_image->arg);
 	typedef void (*image_entry_arg_t)(char *, ulong, ulong)
 		__attribute__ ((noreturn));
 	image_entry_arg_t image_entry =
 		(image_entry_arg_t)spl_image->entry_point;
 
-	image_entry(NULL, 0, (ulong)arg);
+	image_entry(NULL, 0, (ulong)spl_image->arg);
 }
 #endif /* CONFIG_SPL_OS_BOOT */
 

arch/powerpc/lib/spl.c

@@ -14,18 +14,18 @@ DECLARE_GLOBAL_DATA_PTR;
 /*
  * This function jumps to an image with argument. Normally an FDT or ATAGS
  * image.
- * arg: Pointer to paramter image in RAM
  */
 #ifdef CONFIG_SPL_OS_BOOT
-void __noreturn jump_to_image_linux(struct spl_image_info *spl_image, void *arg)
+void __noreturn jump_to_image_linux(struct spl_image_info *spl_image)
 {
-	debug("Entering kernel arg pointer: 0x%p\n", arg);
+	debug("Entering kernel arg pointer: 0x%p\n", spl_image->arg);
 	typedef void (*image_entry_arg_t)(void *, ulong r4, ulong r5, ulong r6,
 					  ulong r7, ulong r8, ulong r9)
 		__attribute__ ((noreturn));
 	image_entry_arg_t image_entry =
 		(image_entry_arg_t)spl_image->entry_point;
 
-	image_entry(arg, 0, 0, EPAPR_MAGIC, CONFIG_SYS_BOOTMAPSZ, 0, 0);
+	image_entry(spl_image->arg, 0, 0, EPAPR_MAGIC, CONFIG_SYS_BOOTMAPSZ,
+		    0, 0);
 }
 #endif /* CONFIG_SPL_OS_BOOT */

common/spl/spl.c

@@ -345,6 +345,9 @@ void board_init_r(gd_t *dummy1, ulong dummy2)
 #endif
 
 	memset(&spl_image, '\0', sizeof(spl_image));
+#ifdef CONFIG_SYS_SPL_ARGS_ADDR
+	spl_image.arg = (void *)CONFIG_SYS_SPL_ARGS_ADDR;
+#endif
 	board_boot_order(spl_boot_list);
 
 	if (boot_from_devices(&spl_image, spl_boot_list,
@@ -361,8 +364,7 @@ void board_init_r(gd_t *dummy1, ulong dummy2)
 	case IH_OS_LINUX:
 		debug("Jumping to Linux\n");
 		spl_board_prepare_for_linux();
-		jump_to_image_linux(&spl_image,
-				    (void *)CONFIG_SYS_SPL_ARGS_ADDR);
+		jump_to_image_linux(&spl_image);
 #endif
 	default:
 		debug("Unsupported OS image.. Jumping nevertheless..\n");

common/spl/spl_nor.c

@@ -39,13 +39,7 @@ static int spl_nor_load_image(struct spl_image_info *spl_image,
 					sizeof(struct image_header)),
 			       spl_image->size);
 
-			/*
-			 * Copy DT blob (fdt) to SDRAM. Passing pointer to
-			 * flash doesn't work
-			 */
-			memcpy((void *)CONFIG_SYS_SPL_ARGS_ADDR,
-			       (void *)(CONFIG_SYS_FDT_BASE),
-			       CONFIG_SYS_FDT_SIZE);
+			spl_image->arg = (void *)CONFIG_SYS_FDT_BASE;
 
 			return 0;
 		} else {

include/spl.h

@@ -27,6 +27,7 @@ struct spl_image_info {
 	ulong entry_point;
 	u32 size;
 	u32 flags;
+	void *arg;
 };
 
 /*
@@ -106,10 +107,8 @@ int spl_board_ubi_load_image(u32 boot_device);
  * This jumps into a Linux kernel using the information in @spl_image.
  *
  * @spl_image: Image description to set up
- * @arg: Argument to pass to Linux (typically a device tree pointer)
  */
-void __noreturn jump_to_image_linux(struct spl_image_info *spl_image,
-				    void *arg);
+void __noreturn jump_to_image_linux(struct spl_image_info *spl_image);
 
 /**
  * spl_start_uboot() - Check if SPL should start the kernel or U-Boot