mpc83xx: Add NAND boot support for MPC8315E-RDB boards

The core support for NAND booting is there already, so this patch
is pretty straightforward.

There is one trick though: top level Makefile expects nand_spl to
be in nand_spl/board/$(BOARDDIR), but we can fully reuse the code
from mpc8313erdb boards, and so to not duplicate the code we just
symlink nand_spl/board/freescale/mpc8315erdb to mpc8313erdb.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>

o silence make during ln echo
o update documentation
o and avoid:

$ ./MAKEALL MPC8315ERDB_NAND
Configuring for MPC8315ERDB board...
sdram.o: In function `fixed_sdram':
/home/r1aaha/git/u-boot/nand_spl/board/freescale/mpc8313erdb/sdram.c:72: undefined reference to `udelay'

by renaming udelay -> __udelay in the spirit of commit
3eb90bad651fab39cffba750ec4421a9c01d60e7 "Generic udelay() with watchdog
support".

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>

3 files changed, 58 insertions, 1 deletions

diff --git a/board/freescale/mpc8315erdb/config.mk b/board/freescale/mpc8315erdb/config.mk
index f76826495e..bf972fbe56 100644
--- a/board/freescale/mpc8315erdb/config.mk
+++ b/board/freescale/mpc8315erdb/config.mk
@@ -1 +1,9 @@
+ifndef NAND_SPL
+ifeq ($(CONFIG_MK_NAND), y)
+TEXT_BASE = $(CONFIG_RAMBOOT_TEXT_BASE)
+endif
+endif
+
+ifndef TEXT_BASE
 TEXT_BASE = 0xFE000000
+endif
diff --git a/board/freescale/mpc8315erdb/mpc8315erdb.c b/board/freescale/mpc8315erdb/mpc8315erdb.c
index dea4d6fe7a..d5e71dc522 100644
--- a/board/freescale/mpc8315erdb/mpc8315erdb.c
+++ b/board/freescale/mpc8315erdb/mpc8315erdb.c
@@ -32,6 +32,8 @@
 #include <mpc83xx.h>
 #include <netdev.h>
 #include <asm/io.h>
+#include <ns16550.h>
+#include <nand.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -45,6 +47,8 @@ int board_early_init_f(void)
 	return 0;
 }
 
+#ifndef CONFIG_NAND_SPL
+
 static u8 read_board_info(void)
 {
 	u8 val8;
@@ -220,3 +224,41 @@ int board_eth_init(bd_t *bis)
 	cpu_eth_init(bis);	/* Initialize TSECs first */
 	return pci_eth_init(bis);
 }
+
+#else /* CONFIG_NAND_SPL */
+
+int checkboard(void)
+{
+	puts("Board: Freescale MPC8315ERDB\n");
+	return 0;
+}
+
+void board_init_f(ulong bootflag)
+{
+	board_early_init_f();
+	NS16550_init((NS16550_t)(CONFIG_SYS_IMMR + 0x4500),
+		     CONFIG_SYS_NS16550_CLK / 16 / CONFIG_BAUDRATE);
+	puts("NAND boot... ");
+	init_timebase();
+	initdram(0);
+	relocate_code(CONFIG_SYS_NAND_U_BOOT_RELOC + 0x10000, (gd_t *)gd,
+		      CONFIG_SYS_NAND_U_BOOT_RELOC);
+}
+
+void board_init_r(gd_t *gd, ulong dest_addr)
+{
+	nand_boot();
+}
+
+void putc(char c)
+{
+	if (gd->flags & GD_FLG_SILENT)
+		return;
+
+	if (c == '\n')
+		NS16550_putc((NS16550_t)(CONFIG_SYS_IMMR + 0x4500), '\r');
+
+	NS16550_putc((NS16550_t)(CONFIG_SYS_IMMR + 0x4500), c);
+}
+
+#endif /* CONFIG_NAND_SPL */
diff --git a/board/freescale/mpc8315erdb/sdram.c b/board/freescale/mpc8315erdb/sdram.c
index ead7b1e0de..fe8ec1eab8 100644
--- a/board/freescale/mpc8315erdb/sdram.c
+++ b/board/freescale/mpc8315erdb/sdram.c
@@ -54,6 +54,7 @@ static void resume_from_sleep(void)
  * This is useful for faster booting in configs where the RAM is unlikely
  * to be changed, or for things like NAND booting where space is tight.
  */
+#ifndef CONFIG_SYS_RAMBOOT
 static long fixed_sdram(void)
 {
 	volatile immap_t *im = (volatile immap_t *)CONFIG_SYS_IMMR;
@@ -68,7 +69,7 @@ static long fixed_sdram(void)
 	 * Erratum DDR3 requires a 50ms delay after clearing DDRCDR[DDR_cfg],
 	 * or the DDR2 controller may fail to initialize correctly.
 	 */
-	udelay(50000);
+	__udelay(50000);
 
 	im->ddr.csbnds[0].csbnds = (msize - 1) >> 24;
 	im->ddr.cs_config[0] = CONFIG_SYS_DDR_CS0_CONFIG;
@@ -100,6 +101,12 @@ static long fixed_sdram(void)
 
 	return msize;
 }
+#else
+static long fixed_sdram(void)
+{
+	return CONFIG_SYS_DDR_SIZE * 1024 * 1024;
+}
+#endif /* CONFIG_SYS_RAMBOOT */
 
 phys_size_t initdram(int board_type)
 {