microblaze: Add support for CONFIG_SYS_MALLOC_F_LEN

Create space for dm_init where calloc is called
and malloc_base has to be initialized.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

arch/microblaze/cpu/start.S

@@ -29,8 +29,12 @@ _start:
 	addi	r1, r0, CONFIG_SPL_STACK_ADDR
 	mts	rshr, r1
 	addi	r1, r1, -4	/* Decrement SP to top of memory */
+#else
+#if defined(CONFIG_SYS_MALLOC_F_LEN)
+	addi	r1, r0, CONFIG_SYS_INIT_SP_OFFSET - CONFIG_SYS_MALLOC_F_LEN
 #else
 	addi	r1, r0, CONFIG_SYS_INIT_SP_OFFSET
+#endif
 	mts	rshr, r1
 	addi	r1, r1, -4	/* Decrement SP to top of memory */
 
@@ -152,6 +156,10 @@ clear_bss:
 #ifndef CONFIG_SPL_BUILD
 	or	r5, r0, r0	/* flags - empty */
 	addi    r31, r0, _gd
+#if defined(CONFIG_SYS_MALLOC_F_LEN)
+	addi	r6, r0, CONFIG_SYS_INIT_SP_OFFSET
+	swi	r6, r31, GD_MALLOC_BASE
+#endif
 	brai	board_init_f
 #else
 	addi	r31, r0, CONFIG_SYS_SPL_MALLOC_END

include/configs/microblaze-generic.h

@@ -113,6 +113,7 @@
 #endif
 
 #define CONFIG_SYS_MALLOC_LEN	0xC0000
+#define CONFIG_SYS_MALLOC_F_LEN	1024
 
 /* Stack location before relocation */
 #define CONFIG_SYS_INIT_SP_OFFSET	CONFIG_SYS_TEXT_BASE