OneNAND: Add simple OneNAND SPL

This introduces small OneNAND loader, fitting into 1kB of space (smallest
possible OneNAND RAM size). Some devices equipped with such crappy chips will
use this.

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Scott Wood <scottwood@freescale.com>

V2: Introduce spl_onenand_load_image() to load data from OneNAND in SPL
V3: Cleanup, align with nand_spl. Skip whole blocks.

1 files changed, 146 insertions, 0 deletions

diff --git a/drivers/mtd/onenand/onenand_spl.c b/drivers/mtd/onenand/onenand_spl.c
new file mode 100644
index 000000000..50eaa7188
--- /dev/null
+++ b/drivers/mtd/onenand/onenand_spl.c
@@ -0,0 +1,146 @@
+/*
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ *
+ * Based on code:
+ *	Copyright (C) 2005-2009 Samsung Electronics
+ *	Kyungmin Park <kyungmin.park@samsung.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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 <linux/mtd/onenand_regs.h>
+#include <onenand_uboot.h>
+
+/*
+ * Device geometry:
+ * - 2048b page, 128k erase block.
+ * - 4096b page, 256k erase block.
+ */
+enum onenand_spl_pagesize {
+	PAGE_2K = 2048,
+	PAGE_4K = 4096,
+};
+
+#define ONENAND_PAGES_PER_BLOCK			64
+#define onenand_block_address(block)		(block)
+#define onenand_sector_address(page)		(page << 2)
+#define onenand_buffer_address()		((1 << 3) << 8)
+#define onenand_bufferram_address(block)	(0)
+
+static inline uint16_t onenand_readw(uint32_t addr)
+{
+	return readw(CONFIG_SYS_ONENAND_BASE + addr);
+}
+
+static inline void onenand_writew(uint16_t value, uint32_t addr)
+{
+	writew(value, CONFIG_SYS_ONENAND_BASE + addr);
+}
+
+static enum onenand_spl_pagesize onenand_spl_get_geometry(void)
+{
+	uint32_t dev_id, density;
+
+	if (!onenand_readw(ONENAND_REG_TECHNOLOGY)) {
+		dev_id = onenand_readw(ONENAND_REG_DEVICE_ID);
+		density = dev_id >> ONENAND_DEVICE_DENSITY_SHIFT;
+		density &= ONENAND_DEVICE_DENSITY_MASK;
+
+		if (density < ONENAND_DEVICE_DENSITY_4Gb)
+			return PAGE_2K;
+
+		if (dev_id & ONENAND_DEVICE_IS_DDP)
+			return PAGE_2K;
+	}
+
+	return PAGE_4K;
+}
+
+static int onenand_spl_read_page(uint32_t block, uint32_t page, uint32_t *buf,
+					enum onenand_spl_pagesize pagesize)
+{
+	const uint32_t addr = CONFIG_SYS_ONENAND_BASE + ONENAND_DATARAM;
+	uint32_t offset;
+
+	onenand_writew(onenand_block_address(block),
+			ONENAND_REG_START_ADDRESS1);
+
+	onenand_writew(onenand_bufferram_address(block),
+			ONENAND_REG_START_ADDRESS2);
+
+	onenand_writew(onenand_sector_address(page),
+			ONENAND_REG_START_ADDRESS8);
+
+	onenand_writew(onenand_buffer_address(),
+			ONENAND_REG_START_BUFFER);
+
+	onenand_writew(ONENAND_INT_CLEAR, ONENAND_REG_INTERRUPT);
+
+	onenand_writew(ONENAND_CMD_READ, ONENAND_REG_COMMAND);
+
+	while (!(onenand_readw(ONENAND_REG_INTERRUPT) & ONENAND_INT_READ))
+		continue;
+
+	/* Check for invalid block mark */
+	if (page < 2 && (onenand_readw(ONENAND_SPARERAM) != 0xffff))
+		return 1;
+
+	for (offset = 0; offset < pagesize; offset += 4)
+		buf[offset / 4] = readl(addr + offset);
+
+	return 0;
+}
+
+void onenand_spl_load_image(uint32_t offs, uint32_t size, void *dst)
+{
+	uint32_t *addr = (uint32_t *)dst;
+	uint32_t total_pages;
+	uint32_t block;
+	uint32_t page, rpage;
+	enum onenand_spl_pagesize pagesize;
+	int ret;
+
+	pagesize = onenand_spl_get_geometry();
+
+	/*
+	 * The page can be either 2k or 4k, avoid using DIV_ROUND_UP to avoid
+	 * pulling further unwanted functions into the SPL.
+	 */
+	if (pagesize == 2048) {
+		total_pages = DIV_ROUND_UP(size, 2048);
+		page = offs / 2048;
+	} else {
+		total_pages = DIV_ROUND_UP(size, 4096);
+		page = offs / 4096;
+	}
+
+	for (; page <= total_pages; page++) {
+		block = page / ONENAND_PAGES_PER_BLOCK;
+		rpage = page & (ONENAND_PAGES_PER_BLOCK - 1);
+		ret = onenand_spl_read_page(block, rpage, addr, pagesize);
+		if (ret) {
+			total_pages += ONENAND_PAGES_PER_BLOCK;
+			page += ONENAND_PAGES_PER_BLOCK - 1;
+		} else {
+			addr += pagesize / 4;
+		}
+	}
+}