powerpc/corenet_ds: Slave reads ENV from master when boot from SRIO

When boot from SRIO, slave's ENV can be stored in master's memory space,
then slave can fetch the ENV through SRIO interface.

NOTE: Because the slave can not erase, write master's NOR flash by SRIO
	  interface, so it can not modify the ENV parameters stored in
	  master's NOR flash using "saveenv" or other commands.

Master needs to:
	1. Put the slave's ENV into it's own memory space.
	2. Set an inbound SRIO window covered slave's ENV stored in master's
	   memory space.
Slave needs to:
	1. Set a specific TLB entry in order to fetch ucode and ENV from master.
	2. Set a LAW entry with the TargetID SRIO1 or SRIO2 for ucode and ENV.

Signed-off-by: Liu Gang <Gang.Liu@freescale.com>
Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>

1 files changed, 79 insertions, 0 deletions

diff --git a/common/env_remote.c b/common/env_remote.c
new file mode 100644
index 0000000..3bf0f95
--- /dev/null
+++ b/common/env_remote.c
@@ -0,0 +1,79 @@
+/*
+ * (C) Copyright 2011-2012 Freescale Semiconductor, Inc.
+ *
+ * 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
+ */
+
+/* #define DEBUG */
+
+#include <common.h>
+#include <command.h>
+#include <environment.h>
+#include <linux/stddef.h>
+
+char *env_name_spec = "Remote";
+
+#ifdef ENV_IS_EMBEDDED
+env_t *env_ptr = &environment;
+#else /* ! ENV_IS_EMBEDDED */
+env_t *env_ptr = (env_t *)CONFIG_ENV_ADDR;
+#endif /* ENV_IS_EMBEDDED */
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#if !defined(CONFIG_ENV_OFFSET)
+#define CONFIG_ENV_OFFSET 0
+#endif
+
+uchar env_get_char_spec(int index)
+{
+	return *((uchar *)(gd->env_addr + index));
+}
+
+int env_init(void)
+{
+	if (crc32(0, env_ptr->data, ENV_SIZE) == env_ptr->crc) {
+		gd->env_addr = (ulong)&(env_ptr->data);
+		gd->env_valid = 1;
+		return 0;
+	}
+
+	gd->env_addr = (ulong)default_environment;
+	gd->env_valid = 0;
+	return 0;
+}
+
+#ifdef CONFIG_CMD_SAVEENV
+int saveenv(void)
+{
+#ifdef CONFIG_SRIOBOOT_SLAVE
+	printf("Can not support the 'saveenv' when boot from SRIO!\n");
+	return 1;
+#else
+	return 0;
+#endif
+}
+#endif /* CONFIG_CMD_SAVEENV */
+
+void env_relocate_spec(void)
+{
+#ifndef ENV_IS_EMBEDDED
+	env_import((char *)env_ptr, 1);
+#endif
+}