dm: spl: Allow device tree/driver model in board_init_f()

Add an spl_init() function that does basic init such that board_init_f() can
use simple malloc(), device tree and driver model. Each one is set up only
if enabled for SPL.

Note: We really should refactor SPL such that there is a single
board_init_f() and rename the existing weak board_init_f() functions
provided by boards, calling them from the single board_init_f().

Signed-off-by: Simon Glass <sjg@chromium.org>

common/spl/spl.c

@@ -148,18 +148,12 @@ static void spl_ram_load_image(void)
 }
 #endif
 
-void board_init_r(gd_t *dummy1, ulong dummy2)
+int spl_init(void)
 {
-	u32 boot_device;
 	int ret;
 
-	debug(">>spl:board_init_r()\n");
-
-#if defined(CONFIG_SYS_SPL_MALLOC_START)
-	mem_malloc_init(CONFIG_SYS_SPL_MALLOC_START,
-			CONFIG_SYS_SPL_MALLOC_SIZE);
-	gd->flags |= GD_FLG_FULL_MALLOC_INIT;
-#elif defined(CONFIG_SYS_MALLOC_F_LEN)
+	debug("spl_init()\n");
+#if defined(CONFIG_SYS_MALLOC_F_LEN)
 	gd->malloc_limit = CONFIG_SYS_MALLOC_F_LEN;
 	gd->malloc_ptr = 0;
 #endif
@@ -168,17 +162,36 @@ void board_init_r(gd_t *dummy1, ulong dummy2)
 		ret = fdtdec_setup();
 		if (ret) {
 			debug("fdtdec_setup() returned error %d\n", ret);
-			hang();
+			return ret;
 		}
 	}
 	if (IS_ENABLED(CONFIG_SPL_DM)) {
 		ret = dm_init_and_scan(true);
 		if (ret) {
 			debug("dm_init_and_scan() returned error %d\n", ret);
-			hang();
+			return ret;
 		}
 	}
+	gd->flags |= GD_FLG_SPL_INIT;
+
+	return 0;
+}
 
+void board_init_r(gd_t *dummy1, ulong dummy2)
+{
+	u32 boot_device;
+
+	debug(">>spl:board_init_r()\n");
+
+#if defined(CONFIG_SYS_SPL_MALLOC_START)
+	mem_malloc_init(CONFIG_SYS_SPL_MALLOC_START,
+			CONFIG_SYS_SPL_MALLOC_SIZE);
+	gd->flags |= GD_FLG_FULL_MALLOC_INIT;
+#endif
+	if (!(gd->flags & GD_FLG_SPL_INIT)) {
+		if (spl_init())
+			hang();
+	}
 #ifndef CONFIG_PPC
 	/*
 	 * timer_init() does not exist on PPC systems. The timer is initialized

include/asm-generic/global_data.h

@@ -116,5 +116,6 @@ typedef struct global_data {
 #define GD_FLG_ENV_READY	0x00080	/* Env. imported into hash table   */
 #define GD_FLG_SERIAL_READY	0x00100	/* Pre-reloc serial console ready  */
 #define GD_FLG_FULL_MALLOC_INIT	0x00200	/* Full malloc() is ready	   */
+#define GD_FLG_SPL_INIT		0x00400	/* spl_init() has been called	   */
 
 #endif /* __ASM_GENERIC_GBL_DATA_H */

include/spl.h

@@ -81,6 +81,18 @@ void __noreturn jump_to_image_no_args(struct spl_image_info *spl_image);
 int spl_load_image_ext(block_dev_desc_t *block_dev, int partition, const char *filename);
 int spl_load_image_ext_os(block_dev_desc_t *block_dev, int partition);
 
+/**
+ * spl_init() - Set up device tree and driver model in SPL if enabled
+ *
+ * Call this function in board_init_f() if you want to use device tree and
+ * driver model early, before board_init_r() is called. This function will
+ * be called from board_init_r() if not called earlier.
+ *
+ * If this is not called, then driver model will be inactive in SPL's
+ * board_init_f(), and no device tree will be available.
+ */
+int spl_init(void);
+
 #ifdef CONFIG_SPL_BOARD_INIT
 void spl_board_init(void);
 #endif