AT91SAM9XE: add embedded flash support

Signed-off-by: Reinhard Meyer <u-boot@emk-elektronik.de>
diff --git a/arch/arm/cpu/arm926ejs/at91/Makefile b/arch/arm/cpu/arm926ejs/at91/Makefile
index 4f467be..def3980 100644
--- a/arch/arm/cpu/arm926ejs/at91/Makefile
+++ b/arch/arm/cpu/arm926ejs/at91/Makefile
@@ -34,6 +34,7 @@
 COBJS-$(CONFIG_AT91SAM9RL)	+= at91sam9rl_devices.o
 COBJS-$(CONFIG_AT91SAM9M10G45)	+= at91sam9m10g45_devices.o
 COBJS-$(CONFIG_AT91SAM9G45)	+= at91sam9m10g45_devices.o
+COBJS-$(CONFIG_AT91_EFLASH)	+= eflash.o
 COBJS-$(CONFIG_AT91_LED)	+= led.o
 COBJS-y += clock.o
 COBJS-y += cpu.o
diff --git a/arch/arm/cpu/arm926ejs/at91/eflash.c b/arch/arm/cpu/arm926ejs/at91/eflash.c
new file mode 100644
index 0000000..2e851db
--- /dev/null
+++ b/arch/arm/cpu/arm926ejs/at91/eflash.c
@@ -0,0 +1,271 @@
+/*
+ * (C) Copyright 2010
+ * Reinhard Meyer, EMK Elektronik, reinhard.meyer@emk-elektronik.de
+ *
+ * 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
+ */
+
+/*
+ * this driver supports the enhanced embedded flash in the Atmel
+ * AT91SAM9XE devices with the following geometry:
+ *
+ * AT91SAM9XE128: 1 plane of  8 regions of 32 pages (total  256 pages)
+ * AT91SAM9XE256: 1 plane of 16 regions of 32 pages (total  512 pages)
+ * AT91SAM9XE512: 1 plane of 32 regions of 32 pages (total 1024 pages)
+ * (the exact geometry is read from the flash at runtime, so any
+ *  future devices should already be covered)
+ *
+ * Regions can be write/erase protected.
+ * Whole (!) pages can be individually written with erase on the fly.
+ * Writing partial pages will corrupt the rest of the page.
+ *
+ * The flash is presented to u-boot with each region being a sector,
+ * having the following effects:
+ * Each sector can be hardware protected (protect on/off).
+ * Each page in a sector can be rewritten anytime.
+ * Since pages are erased when written, the "erase" does nothing.
+ * The first "CONFIG_EFLASH_PROTSECTORS" cannot be unprotected
+ * by u-Boot commands.
+ *
+ * Note: Redundant environment will not work in this flash since
+ * it does use partial page writes. Make sure the environent spans
+ * whole pages!
+ */
+
+/*
+ * optional TODOs (nice to have features):
+ *
+ * make the driver coexist with other NOR flash drivers
+ *	(use an index into flash_info[], requires work
+ *	in those other drivers, too)
+ * Make the erase command fill the sectors with 0xff
+ *	(if the flashes grow larger in the future and
+ *	someone puts a jffs2 into them)
+ * do a read-modify-write for partially programmed pages
+ */
+#include <common.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/io.h>
+#include <asm/arch/at91_common.h>
+#include <asm/arch/at91_eefc.h>
+#include <asm/arch/at91_dbu.h>
+
+/* checks to detect configuration errors */
+#if CONFIG_SYS_MAX_FLASH_BANKS!=1
+#error eflash: this driver can only handle 1 bank
+#endif
+
+/* global structure */
+flash_info_t flash_info[CONFIG_SYS_MAX_FLASH_BANKS];
+static u32 pagesize;
+
+unsigned long flash_init (void)
+{
+	at91_eefc_t *eefc = (at91_eefc_t *) 0xfffffa00;
+	at91_dbu_t *dbu = (at91_dbu_t *) 0xfffff200;
+	u32 id, size, nplanes, planesize, nlocks;
+	u32 addr, i, tmp=0;
+
+	debug("eflash: init\n");
+
+	flash_info[0].flash_id = FLASH_UNKNOWN;
+
+	/* check if its an AT91ARM9XE SoC */
+	if ((readl(&dbu->cidr) & AT91_DBU_CID_ARCH_MASK) != AT91_DBU_CID_ARCH_9XExx) {
+		puts("eflash: not an AT91SAM9XE\n");
+		return 0;
+	}
+
+	/* now query the eflash for its structure */
+	writel(AT91_EEFC_FCR_KEY | AT91_EEFC_FCR_FCMD_GETD, &eefc->fcr);
+	while ((readl(&eefc->fsr) & AT91_EEFC_FSR_FRDY) == 0)
+		;
+	id = readl(&eefc->frr);		/* word 0 */
+	size = readl(&eefc->frr);	/* word 1 */
+	pagesize = readl(&eefc->frr);	/* word 2 */
+	nplanes = readl(&eefc->frr);	/* word 3 */
+	planesize = readl(&eefc->frr);	/* word 4 */
+	debug("id=%08x size=%u pagesize=%u planes=%u planesize=%u\n",
+		id, size, pagesize, nplanes, planesize);
+	for (i=1; i<nplanes; i++) {
+		tmp = readl(&eefc->frr);	/* words 5..4+nplanes-1 */
+	};
+	nlocks = readl(&eefc->frr);	/* word 4+nplanes */
+	debug("nlocks=%u\n", nlocks);
+	/* since we are going to use the lock regions as sectors, check count */
+	if (nlocks > CONFIG_SYS_MAX_FLASH_SECT) {
+		printf("eflash: number of lock regions(%u) "\
+			"> CONFIG_SYS_MAX_FLASH_SECT. reducing...\n",
+			nlocks);
+		nlocks = CONFIG_SYS_MAX_FLASH_SECT;
+	}
+	flash_info[0].size = size;
+	flash_info[0].sector_count = nlocks;
+	flash_info[0].flash_id = id;
+
+	addr = AT91SAM9XE_FLASH_BASE;
+	for (i=0; i<nlocks; i++) {
+		tmp = readl(&eefc->frr);	/* words 4+nplanes+1.. */
+		flash_info[0].start[i] = addr;
+		flash_info[0].protect[i] = 0;
+		addr += tmp;
+	};
+
+	/* now read the protection information for all regions */
+	writel(AT91_EEFC_FCR_KEY | AT91_EEFC_FCR_FCMD_GLB, &eefc->fcr);
+	while ((readl(&eefc->fsr) & AT91_EEFC_FSR_FRDY) == 0)
+		;
+	for (i=0; i<flash_info[0].sector_count; i++) {
+		if (i%32 == 0)
+			tmp = readl(&eefc->frr);
+		flash_info[0].protect[i] = (tmp >> (i%32)) & 1;
+#if defined(CONFIG_EFLASH_PROTSECTORS)
+		if (i < CONFIG_EFLASH_PROTSECTORS)
+			flash_info[0].protect[i] = 1;
+#endif
+	}
+
+	return size;
+}
+
+void flash_print_info (flash_info_t *info)
+{
+	int i;
+
+	puts("AT91SAM9XE embedded flash\n  Size: ");
+	print_size(info->size, " in ");
+	printf("%d Sectors\n", info->sector_count);
+
+	printf("  Sector Start Addresses:");
+	for (i=0; i<info->sector_count; ++i) {
+		if ((i % 5) == 0)
+			printf("\n   ");
+		printf(" %08lX%s",
+			info->start[i],
+			info->protect[i] ? " (RO)" : "     "
+		);
+	}
+	printf ("\n");
+	return;
+}
+
+int flash_real_protect (flash_info_t *info, long sector, int prot)
+{
+	at91_eefc_t *eefc = (at91_eefc_t *) 0xfffffa00;
+	u32 pagenum = (info->start[sector]-AT91SAM9XE_FLASH_BASE)/pagesize;
+	u32 i, tmp=0;
+
+	debug("protect sector=%ld prot=%d\n", sector, prot);
+
+#if defined(CONFIG_EFLASH_PROTSECTORS)
+	if (sector < CONFIG_EFLASH_PROTSECTORS) {
+		if (!prot) {
+			printf("eflash: sector %lu cannot be unprotected\n",
+				sector);
+		}
+		return 1; /* return anyway, caller does not care for result */
+	}
+#endif
+	if (prot) {
+		writel(AT91_EEFC_FCR_KEY | AT91_EEFC_FCR_FCMD_SLB |
+			(pagenum << AT91_EEFC_FCR_FARG_SHIFT), &eefc->fcr);
+	} else {
+		writel(AT91_EEFC_FCR_KEY | AT91_EEFC_FCR_FCMD_CLB |
+			(pagenum << AT91_EEFC_FCR_FARG_SHIFT), &eefc->fcr);
+	}
+	while ((readl(&eefc->fsr) & AT91_EEFC_FSR_FRDY) == 0)
+		;
+	/* now re-read the protection information for all regions */
+	writel(AT91_EEFC_FCR_KEY | AT91_EEFC_FCR_FCMD_GLB, &eefc->fcr);
+	while ((readl(&eefc->fsr) & AT91_EEFC_FSR_FRDY) == 0)
+		;
+	for (i=0; i<info->sector_count; i++) {
+		if (i%32 == 0)
+			tmp = readl(&eefc->frr);
+		info->protect[i] = (tmp >> (i%32)) & 1;
+	}
+	return 0;
+}
+
+static u32 erase_write_page (u32 pagenum)
+{
+	at91_eefc_t *eefc = (at91_eefc_t *) 0xfffffa00;
+
+	debug("erase+write page=%u\n", pagenum);
+
+	/* give erase and write page command */
+	writel(AT91_EEFC_FCR_KEY | AT91_EEFC_FCR_FCMD_EWP |
+		(pagenum << AT91_EEFC_FCR_FARG_SHIFT), &eefc->fcr);
+	while ((readl(&eefc->fsr) & AT91_EEFC_FSR_FRDY) == 0)
+		;
+	/* return status */
+	return readl(&eefc->fsr)
+		& (AT91_EEFC_FSR_FCMDE | AT91_EEFC_FSR_FLOCKE);
+}
+
+int flash_erase (flash_info_t *info, int s_first, int s_last)
+{
+	debug("erase first=%d last=%d\n", s_first, s_last);
+	puts("this flash does not need and support erasing!\n");
+	return 0;
+}
+
+/*
+ * Copy memory to flash, returns:
+ * 0 - OK
+ * 1 - write timeout
+ */
+
+int write_buff (flash_info_t *info, uchar *src, ulong addr, ulong cnt)
+{
+	u32 pagenum;
+	u32 *src32, *dst32;
+	u32 i;
+
+	debug("write src=%08lx addr=%08lx cnt=%lx\n",
+		(ulong)src, addr, cnt);
+
+	/* REQUIRE addr to be on a page start, abort if not */
+	if (addr % pagesize) {
+		printf ("eflash: start %08lx is not on page start\n"\
+			"        write aborted\n", addr);
+		return 1;
+	}
+
+	/* now start copying data */
+	pagenum = (addr-AT91SAM9XE_FLASH_BASE)/pagesize;
+	src32 = (u32 *) src;
+	dst32 = (u32 *) addr;
+	while (cnt > 0) {
+		i = pagesize / 4;
+		/* fill page buffer */
+		while (i--)
+			*dst32++ = *src32++;
+		/* write page */
+		if (erase_write_page(pagenum))
+			return 1;
+		pagenum++;
+		if (cnt > pagesize)
+			cnt -= pagesize;
+		else
+			cnt = 0;
+	}
+	return 0;
+}
+