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+/*
+ * Copyright (C) 2001, 2002 ETC s.r.o.
+ *
+ * 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.
+ *
+ * Written by Marcel Telka <marcel@telka.sk>, 2001, 2002.
+ * Changes for U-Boot Peter Figuli <peposh@etc.sk>, 2003.
+ *
+ * This file is taken from OpenWinCE project hosted by SourceForge.net
+ *
+ * Documentation:
+ * [1] Intel Corporation, "Intel PXA250 and PXA210 Application Processors
+ * Developer's Manual", February 2002, Order Number: 278522-001
+ * [2] Samsung Electronics, "8Mx16 SDRAM 54CSP K4S281633D-RL/N/P",
+ * Revision 1.0, February 2002
+ * [3] Samsung Electronics, "16Mx16 SDRAM 54CSP K4S561633C-RL(N)",
+ * Revision 1.0, February 2002
+ *
+*/
+
+#include <config.h>
+#include <version.h>
+#include <asm/arch/pxa-regs.h>
+
+.globl lowlevel_init
+lowlevel_init:
+
+ mov r10, lr
+
+/* setup memory - see 6.12 in [1]
+ * Step 1 - wait 200 us
+ */
+ mov r0,#0x2700 /* wait 200 us @ 99.5 MHz */
+1: subs r0, r0, #1
+ bne 1b
+/* TODO: complete step 1 for Synchronous Static memory*/
+
+ ldr r0, =0x48000000 /* MC_BASE */
+
+
+/* step 1.a - setup MSCx
+ */
+ ldr r1, =0x000012B3 /* MSC0_RRR0(1) | MSC0_RDN0(2) | MSC0_RDF0(11) | MSC0_RT0(3) */
+ str r1, [r0, #0x8] /* MSC0_OFFSET */
+
+/* step 1.c - clear MDREFR:K1FREE, set MDREFR:DRI
+ * see AUTO REFRESH chapter in section D. in [2] and in [3]
+ * DRI = (64ms / 4096) * 99.53MHz / 32 = 48 for K4S281633
+ * DRI = (64ms / 8192) * 99.52MHz / 32 = 24 for K4S561633
+ * TODO: complete for Synchronous Static memory
+ */
+ ldr r1, [r0, #4] /* MDREFR_OFFSET */
+ ldr r2, =0x01000FFF /* MDREFR_K1FREE | MDREFR_DRI_MASK */
+ bic r1, r1, r2
+#if defined( WEP_SDRAM_K4S281633 )
+ orr r1, r1, #48 /* MDREFR_DRI(48) */
+#elif defined( WEP_SDRAM_K4S561633 )
+ orr r1, r1, #24 /* MDREFR_DRI(24) */
+#else
+#error SDRAM chip is not defined
+#endif
+
+ str r1, [r0, #4] /* MDREFR_OFFSET */
+
+/* Step 2 - only for Synchronous Static memory (TODO)
+ *
+ * Step 3 - same as step 4
+ *
+ * Step 4
+ *
+ * Step 4.a - set MDREFR:K1RUN, clear MDREFR:K1DB2
+ */
+ orr r1, r1, #0x00010000 /* MDREFR_K1RUN */
+ bic r1, r1, #0x00020000 /* MDREFR_K1DB2 */
+ str r1, [r0, #4] /* MDREFR_OFFSET */
+
+/* Step 4.b - clear MDREFR:SLFRSH */
+ bic r1, r1, #0x00400000 /* MDREFR_SLFRSH */
+ str r1, [r0, #4] /* MDREFR_OFFSET */
+
+/* Step 4.c - set MDREFR:E1PIN */
+ orr r1, r1, #0x00008000 /* MDREFR_E1PIN */
+ str r1, [r0, #4] /* MDREFR_OFFSET */
+
+/* Step 4.d - automatically done
+ *
+ * Steps 4.e and 4.f - configure SDRAM
+ */
+#if defined( WEP_SDRAM_K4S281633 )
+ ldr r1, =0x00000AA8 /* MDCNFG_DTC0(2) | MDCNFG_DLATCH0 | MDCNFG_DCAC0(1) | MDCNFG_DRAC0(1) | MDCNFG_DNB0 */
+#elif defined( WEP_SDRAM_K4S561633 )
+ ldr r1, =0x00000AC8 /* MDCNFG_DTC0(2) | MDCNFG_DLATCH0 | MDCNFG_DCAC0(1) | MDCNFG_DRAC0(2) | MDCNFG_DNB0 */
+#else
+#error SDRAM chip is not defined
+#endif
+ str r1, [r0, #0] /* MDCNFG_OFFSET */
+
+/* Step 5 - wait at least 200 us for SDRAM
+ * see section B. in [2]
+ */
+ mov r2,#0x2700 /* wait 200 us @ 99.5 MHz */
+1: subs r2, r2, #1
+ bne 1b
+
+/* Step 6 - after reset dcache is disabled, so automatically done
+ *
+ * Step 7 - eight refresh cycles
+ */
+ mov r2, #0xA0000000
+ ldr r3, [r2]
+ ldr r3, [r2]
+ ldr r3, [r2]
+ ldr r3, [r2]
+ ldr r3, [r2]
+ ldr r3, [r2]
+ ldr r3, [r2]
+ ldr r3, [r2]
+
+/* Step 8 - we don't need dcache now
+ *
+ * Step 9 - enable SDRAM partition 0
+ */
+ orr r1, r1, #1 /* MDCNFG_DE0 */
+ str r1, [r0, #0] /* MDCNFG_OFFSET */
+
+/* Step 10 - write MDMRS */
+ mov r1, #0
+ str r1, [r0, #0x40] /* MDMRS_OFFSET */
+
+/* Step 11 - optional (TODO) */
+
+ mov pc,r10