Add support for environment in SPI flash

This is pretty incomplete...it doesn't handle reading the environment
before relocation, it doesn't support redundant environment, and it
doesn't support embedded environment. But apart from that, it does
seem to work.

Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>

common/Makefile

@@ -113,6 +113,7 @@ COBJS-y += env_dataflash.o
 COBJS-y += env_flash.o
 COBJS-y += env_eeprom.o
 COBJS-y += env_onenand.o
+COBJS-y += env_sf.o
 COBJS-y += env_nvram.o
 COBJS-y += env_nowhere.o
 COBJS-y += exports.o

common/cmd_nvedit.c

@@ -58,8 +58,9 @@ DECLARE_GLOBAL_DATA_PTR;
     !defined(CFG_ENV_IS_IN_DATAFLASH)	&& \
     !defined(CFG_ENV_IS_IN_NAND)	&& \
     !defined(CFG_ENV_IS_IN_ONENAND)	&& \
+    !defined(CFG_ENV_IS_IN_SPI_FLASH)	&& \
     !defined(CFG_ENV_IS_NOWHERE)
-# error Define one of CFG_ENV_IS_IN_{NVRAM|EEPROM|FLASH|DATAFLASH|ONENAND|NOWHERE}
+# error Define one of CFG_ENV_IS_IN_{NVRAM|EEPROM|FLASH|DATAFLASH|ONENAND|SPI_FLASH|NOWHERE}
 #endif
 
 #define XMK_STR(x)	#x

common/env_common.c

@@ -134,7 +134,8 @@ uchar default_environment[] = {
 	"\0"
 };
 
-#if defined(CFG_ENV_IS_IN_NAND)		/* Environment is in Nand Flash */
+#if defined(CFG_ENV_IS_IN_NAND)		/* Environment is in Nand Flash */ \
+	|| defined(CFG_ENV_IS_IN_SPI_FLASH)
 int default_environment_size = sizeof(default_environment);
 #endif
 

common/env_sf.c

@@ -0,0 +1,131 @@
+/*
+ * (C) Copyright 2000-2002
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Andreas Heppel <aheppel@sysgo.de>
+ *
+ * (C) Copyright 2008 Atmel Corporation
+ *
+ * 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>
+
+#ifdef CFG_ENV_IS_IN_SPI_FLASH
+
+#include <environment.h>
+#include <spi_flash.h>
+
+#ifndef CFG_ENV_SPI_BUS
+# define CFG_ENV_SPI_BUS	0
+#endif
+#ifndef CFG_ENV_SPI_CS
+# define CFG_ENV_SPI_CS		0
+#endif
+#ifndef CFG_ENV_SPI_MAX_HZ
+# define CFG_ENV_SPI_MAX_HZ	1000000
+#endif
+#ifndef CFG_ENV_SPI_MODE
+# define CFG_ENV_SPI_MODE	SPI_MODE_3
+#endif
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* references to names in env_common.c */
+extern uchar default_environment[];
+extern int default_environment_size;
+
+char * env_name_spec = "SPI Flash";
+env_t *env_ptr;
+
+static struct spi_flash *env_flash;
+
+uchar env_get_char_spec(int index)
+{
+	return *((uchar *)(gd->env_addr + index));
+}
+
+int saveenv(void)
+{
+	if (!env_flash) {
+		puts("Environment SPI flash not initialized\n");
+		return 1;
+	}
+
+	puts("Erasing SPI flash...");
+	if (spi_flash_erase(env_flash, CFG_ENV_OFFSET, CFG_ENV_SIZE))
+		return 1;
+
+	puts("Writing to SPI flash...");
+	if (spi_flash_write(env_flash, CFG_ENV_OFFSET, CFG_ENV_SIZE, env_ptr))
+		return 1;
+
+	puts("done\n");
+	return 0;
+}
+
+void env_relocate_spec(void)
+{
+	int ret;
+
+	env_flash = spi_flash_probe(CFG_ENV_SPI_BUS, CFG_ENV_SPI_CS,
+			CFG_ENV_SPI_MAX_HZ, CFG_ENV_SPI_MODE);
+	if (!env_flash)
+		goto err_probe;
+
+	ret = spi_flash_read(env_flash, CFG_ENV_OFFSET, CFG_ENV_SIZE, env_ptr);
+	if (ret)
+		goto err_read;
+
+	if (crc32(0, env_ptr->data, ENV_SIZE) != env_ptr->crc)
+		goto err_crc;
+
+	gd->env_valid = 1;
+
+	return;
+
+err_read:
+	spi_flash_free(env_flash);
+	env_flash = NULL;
+err_probe:
+err_crc:
+	puts("*** Warning - bad CRC, using default environment\n\n");
+
+	if (default_environment_size > CFG_ENV_SIZE) {
+		gd->env_valid = 0;
+		puts("*** Error - default environment is too large\n\n");
+		return;
+	}
+
+	memset(env_ptr, 0, sizeof(env_t));
+	memcpy(env_ptr->data, default_environment, default_environment_size);
+	env_ptr->crc = crc32(0, env_ptr->data, ENV_SIZE);
+	gd->env_valid = 1;
+}
+
+int env_init(void)
+{
+	/* SPI flash isn't usable before relocation */
+	gd->env_addr = (ulong)&default_environment[0];
+	gd->env_valid = 1;
+
+	return 0;
+}
+
+#endif /* CFG_ENV_IS_IN_SPI_FLASH */