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+/*
+ * (C) Copyright 2011
+ * Matthias Weisser <weisserm@arcor.de>
+ *
+ * (C) Copyright 2009 DENX Software Engineering
+ * Author: John Rigby <jrigby@gmail.com>
+ *
+ * Based on U-Boot and RedBoot sources for several different i.mx
+ * platforms.
+ *
+ * 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 <asm/macro.h>
+#include <asm/arch/macro.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/asm-offsets.h>
+
+/*
+ * clocks
+ */
+.macro init_clocks
+
+ /* disable clock output */
+ write32 IMX_CCM_BASE + CCM_MCR, 0x00000000
+ write32 IMX_CCM_BASE + CCM_CCTL, 0x50030000
+
+ /*
+ * enable all implemented clocks in all three
+ * clock control registers
+ */
+ write32 IMX_CCM_BASE + CCM_CGCR0, 0x1fffffff
+ write32 IMX_CCM_BASE + CCM_CGCR1, 0xffffffff
+ write32 IMX_CCM_BASE + CCM_CGCR2, 0xfffff
+
+ /* Devide NAND clock by 32 */
+ write32 IMX_CCM_BASE + CCM_PCDR2, 0x0101011F
+.endm
+
+/*
+ * sdram controller init
+ */
+.macro init_lpddr
+ ldr r0, =IMX_ESDRAMC_BASE
+ ldr r2, =IMX_SDRAM_BANK0_BASE
+
+ /*
+ * reset SDRAM controller
+ * then wait for initialization to complete
+ */
+ ldr r1, =(1 << 1) | (1 << 2)
+ str r1, [r0, #ESDRAMC_ESDMISC]
+1: ldr r3, [r0, #ESDRAMC_ESDMISC]
+ tst r3, #(1 << 31)
+ beq 1b
+ ldr r1, =(1 << 2)
+ str r1, [r0, #ESDRAMC_ESDMISC]
+
+ ldr r1, =0x002a7420
+ str r1, [r0, #ESDRAMC_ESDCFG0]
+
+ /* control | precharge */
+ ldr r1, =0x92216008
+ str r1, [r0, #ESDRAMC_ESDCTL0]
+ /* dram command encoded in address */
+ str r1, [r2, #0x400]
+
+ /* auto refresh */
+ ldr r1, =0xa2216008
+ str r1, [r0, #ESDRAMC_ESDCTL0]
+ /* read dram twice to auto refresh */
+ ldr r3, [r2]
+ ldr r3, [r2]
+
+ /* control | load mode */
+ ldr r1, =0xb2216008
+ str r1, [r0, #ESDRAMC_ESDCTL0]
+
+ /* mode register of lpddram */
+ strb r1, [r2, #0x33]
+
+ /* extended mode register of lpddrram */
+ ldr r2, =0x81000000
+ strb r1, [r2]
+
+ /* control | normal */
+ ldr r1, =0x82216008
+ str r1, [r0, #ESDRAMC_ESDCTL0]
+.endm
+
+.globl lowlevel_init
+lowlevel_init:
+ init_aips
+ init_max
+ init_clocks
+ init_lpddr
+ mov pc, lr
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