powerpc/85xx: Enable eSDHC boot support on P2020 DS

We implement our own mmc_get_env_addr since the environment variables are
written to just after the u-boot image on SDCard, so we must read the MBR
to get the start address and code length of the u-boot image, then
calculate the address of the env.

Signed-off-by: Jerry Huang <Chang-Ming.Huang@freescale.com>
Signed-off-by: Zhao Chenhui <b35336@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/board/freescale/common/Makefile b/board/freescale/common/Makefile
index 1abd3e5..8ea5acb 100644
--- a/board/freescale/common/Makefile
+++ b/board/freescale/common/Makefile
@@ -36,6 +36,7 @@
 COBJS-$(CONFIG_PQ_MDS_PIB)	+= pq-mds-pib.o
 COBJS-$(CONFIG_ID_EEPROM)	+= sys_eeprom.o
 COBJS-$(CONFIG_FSL_SGMII_RISER)	+= sgmii_riser.o
+COBJS-$(CONFIG_ENV_IS_IN_MMC)	+= sdhc_boot.o
 
 COBJS-$(CONFIG_MPC8541CDS)	+= cds_pci_ft.o
 COBJS-$(CONFIG_MPC8548CDS)	+= cds_pci_ft.o
diff --git a/board/freescale/common/sdhc_boot.c b/board/freescale/common/sdhc_boot.c
new file mode 100644
index 0000000..964c6b8
--- /dev/null
+++ b/board/freescale/common/sdhc_boot.c
@@ -0,0 +1,64 @@
+/*
+ * Copyright 2011 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
+ */
+
+#include <common.h>
+#include <mmc.h>
+#include <malloc.h>
+
+/*
+ * The environment variables are written to just after the u-boot image
+ * on SDCard, so we must read the MBR to get the start address and code
+ * length of the u-boot image, then calculate the address of the env.
+ */
+#define ESDHC_BOOT_IMAGE_SIZE	0x48
+#define ESDHC_BOOT_IMAGE_ADDR	0x50
+
+int mmc_get_env_addr(struct mmc *mmc, u32 *env_addr)
+{
+	u8 *tmp_buf;
+	u32 blklen, code_offset, code_len, n;
+
+	blklen = mmc->read_bl_len;
+	tmp_buf = malloc(blklen);
+	if (!tmp_buf)
+		return 1;
+
+	/* read out the first block, get the config data information */
+	n = mmc->block_dev.block_read(mmc->block_dev.dev, 0, 1, tmp_buf);
+	if (!n) {
+		free(tmp_buf);
+		return 1;
+	}
+
+	/* Get the Source Address, from offset 0x50 */
+	code_offset = *(u32 *)(tmp_buf + ESDHC_BOOT_IMAGE_ADDR);
+
+	/* Get the code size from offset 0x48 */
+	code_len = *(u32 *)(tmp_buf + ESDHC_BOOT_IMAGE_SIZE);
+
+	*env_addr = code_offset + code_len;
+
+	free(tmp_buf);
+
+	return 0;
+}
+
diff --git a/board/freescale/p2020ds/tlb.c b/board/freescale/p2020ds/tlb.c
index 824b3b2..fd914a1 100644
--- a/board/freescale/p2020ds/tlb.c
+++ b/board/freescale/p2020ds/tlb.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2008-2009 Freescale Semiconductor, Inc.
+ * Copyright 2008-2011 Freescale Semiconductor, Inc.
  *
  * (C) Copyright 2000
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
@@ -90,6 +90,17 @@
 	SET_TLB_ENTRY(1, PIXIS_BASE, PIXIS_BASE_PHYS,
 		      MAS3_SX|MAS3_SW|MAS3_SR, MAS2_I|MAS2_G,
 		      0, 8, BOOKE_PAGESZ_4K, 1),
+
+#if defined(CONFIG_SYS_RAMBOOT) && defined(CONFIG_SYS_INIT_L2_ADDR)
+	/* *I*G - L2SRAM */
+	SET_TLB_ENTRY(1, CONFIG_SYS_INIT_L2_ADDR, CONFIG_SYS_INIT_L2_ADDR_PHYS,
+		      MAS3_SX|MAS3_SW|MAS3_SR, MAS2_I|MAS2_G,
+		      0, 9, BOOKE_PAGESZ_256K, 1),
+	SET_TLB_ENTRY(1, CONFIG_SYS_INIT_L2_ADDR + 0x40000,
+		      CONFIG_SYS_INIT_L2_ADDR_PHYS + 0x40000,
+		      MAS3_SX|MAS3_SW|MAS3_SR, MAS2_I|MAS2_G,
+		      0, 10, BOOKE_PAGESZ_256K, 1),
+#endif
 };
 
 int num_tlb_entries = ARRAY_SIZE(tlb_table);