NAND boot: MPC8313ERDB support

Note that with older board revisions, NAND boot may only work after a
power-on reset, and not after a warm reset.  I don't have a newer board
to test on; if you have a board with a 33MHz crystal, please let me know
if it works after a warm reset.

Signed-off-by: Scott Wood <scottwood@freescale.com>
diff --git a/nand_spl/nand_boot_fsl_elbc.c b/nand_spl/nand_boot_fsl_elbc.c
new file mode 100644
index 0000000..0d2378e
--- /dev/null
+++ b/nand_spl/nand_boot_fsl_elbc.c
@@ -0,0 +1,150 @@
+/*
+ * NAND boot for Freescale Enhanced Local Bus Controller, Flash Control Machine
+ *
+ * (C) Copyright 2006-2008
+ * Stefan Roese, DENX Software Engineering, sr@denx.de.
+ *
+ * Copyright (c) 2008 Freescale Semiconductor, Inc.
+ * Author: Scott Wood <scottwood@freescale.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/immap_83xx.h>
+#include <asm/fsl_lbc.h>
+#include <linux/mtd/nand.h>
+
+#define WINDOW_SIZE 8192
+
+static void nand_wait(void)
+{
+	lbus83xx_t *regs = (lbus83xx_t *)(CFG_IMMR + 0x5000);
+
+	for (;;) {
+		uint32_t status = in_be32(&regs->ltesr);
+
+		if (status == 1)
+			return;
+
+		if (status & 1) {
+			puts("read failed (ltesr)\n");
+			for (;;);
+		}
+	}
+}
+
+static void nand_load(unsigned int offs, int uboot_size, uchar *dst)
+{
+	lbus83xx_t *regs = (lbus83xx_t *)(CFG_IMMR + 0x5000);
+	uchar *buf = (uchar *)CFG_NAND_BASE;
+	int large = in_be32(&regs->bank[0].or) & OR_FCM_PGS;
+	int block_shift = large ? 17 : 14;
+	int block_size = 1 << block_shift;
+	int page_size = large ? 2048 : 512;
+	int bad_marker = large ? page_size + 0 : page_size + 5;
+	int fmr = (15 << FMR_CWTO_SHIFT) | (2 << FMR_AL_SHIFT) | 2;
+	int pos = 0;
+
+	if (offs & (block_size - 1)) {
+		puts("bad offset\n");
+		for (;;);
+	}
+
+	if (large) {
+		fmr |= FMR_ECCM;
+		out_be32(&regs->fcr, (NAND_CMD_READ0 << FCR_CMD0_SHIFT) |
+		                     (NAND_CMD_READSTART << FCR_CMD1_SHIFT));
+		out_be32(&regs->fir,
+		         (FIR_OP_CW0 << FIR_OP0_SHIFT) |
+		         (FIR_OP_CA  << FIR_OP1_SHIFT) |
+		         (FIR_OP_PA  << FIR_OP2_SHIFT) |
+		         (FIR_OP_CW1 << FIR_OP3_SHIFT) |
+		         (FIR_OP_RBW << FIR_OP4_SHIFT));
+	} else {
+		out_be32(&regs->fcr, NAND_CMD_READ0 << FCR_CMD0_SHIFT);
+		out_be32(&regs->fir,
+		         (FIR_OP_CW0 << FIR_OP0_SHIFT) |
+		         (FIR_OP_CA  << FIR_OP1_SHIFT) |
+		         (FIR_OP_PA  << FIR_OP2_SHIFT) |
+		         (FIR_OP_RBW << FIR_OP3_SHIFT));
+	}
+
+	out_be32(&regs->fbcr, 0);
+	clrsetbits_be32(&regs->bank[0].br, BR_DECC, BR_DECC_CHK_GEN);
+
+	while (pos < uboot_size) {
+		int i = 0;
+		out_be32(&regs->fbar, offs >> block_shift);
+
+		do {
+			int j;
+			unsigned int page_offs = (offs & (block_size - 1)) << 1;
+
+			out_be32(&regs->ltesr, ~0);
+			out_be32(&regs->lteatr, 0);
+			out_be32(&regs->fpar, page_offs);
+			out_be32(&regs->fmr, fmr);
+			out_be32(&regs->lsor, 0);
+			nand_wait();
+
+			page_offs %= WINDOW_SIZE;
+
+			/*
+			 * If either of the first two pages are marked bad,
+			 * continue to the next block.
+			 */
+			if (i++ < 2 && buf[page_offs + bad_marker] != 0xff) {
+				puts("skipping\n");
+				offs = (offs + block_size) & ~(block_size - 1);
+				pos &= ~(block_size - 1);
+				break;
+			}
+
+			for (j = 0; j < page_size; j++)
+				dst[pos + j] = buf[page_offs + j];
+
+			pos += page_size;
+			offs += page_size;
+		} while (offs & (block_size - 1));
+	}
+}
+
+/*
+ * The main entry for NAND booting. It's necessary that SDRAM is already
+ * configured and available since this code loads the main U-Boot image
+ * from NAND into SDRAM and starts it from there.
+ */
+void nand_boot(void)
+{
+	__attribute__((noreturn)) void (*uboot)(void);
+
+	udelay(1000000);
+
+	/*
+	 * Load U-Boot image from NAND into RAM
+	 */
+	nand_load(CFG_NAND_U_BOOT_OFFS, CFG_NAND_U_BOOT_SIZE,
+	          (uchar *)CFG_NAND_U_BOOT_DST);
+
+	/*
+	 * Jump to U-Boot image
+	 */
+	puts("transfering control\n");
+	uboot = (void *)CFG_NAND_U_BOOT_START;
+	uboot();
+}