2 * Copyright (C) 2004 Sascha Hauer, Synertronixx GmbH
4 * SPDX-License-Identifier: GPL-2.0+
8 #include <asm/arch/imx-regs.h>
15 /* Change PERCLK1DIV to 14 ie 14+1 */
17 ldr r1, =CONFIG_SYS_PCDR_VAL
20 /* set MCU PLL Control Register 0 */
23 ldr r1, =CONFIG_SYS_MPCTL0_VAL
26 /* set mpll restart bit */
42 /* set System PLL Control Register 0 */
45 ldr r1, =CONFIG_SYS_SPCTL0_VAL
48 /* set spll restart bit */
65 ldr r1, =CONFIG_SYS_CSCR_VAL
68 /* I have now read the ARM920 DataSheet back-to-Back, and have stumbled upon
71 * It would appear that from a Cold-Boot the ARM920T enters "FastBus" mode CP15
72 * register 1, this stops it using the output of the PLL and thus runs at the
73 * slow rate. Unless you place the Core into "Asynch" mode, the CPU will never
74 * use the value set in the CM_OSC registers...regardless of what you set it
75 * too! Thus, although i thought i was running at 140MHz, i'm actually running
78 * Slapping this into my bootloader does the trick...
80 * MRC p15,0,r0,c1,c0,0 ; read core configuration register
81 * ORR r0,r0,#0xC0000000 ; set asynchronous clocks and not fastbus mode
82 * MCR p15,0,r0,c1,c0,0 ; write modified value to core configuration
90 ldr r1, =CONFIG_SYS_GPR_A_VAL
94 ldr r1, =CONFIG_SYS_GIUS_A_VAL
97 /* CS3 becomes CS3 by clearing reset default bit 1 in FMCR */
100 ldr r1, =CONFIG_SYS_FMCR_VAL
104 ldr r1, =CONFIG_SYS_CS0U_VAL
108 ldr r1, =CONFIG_SYS_CS0L_VAL
112 ldr r1, =CONFIG_SYS_CS1U_VAL
116 ldr r1, =CONFIG_SYS_CS1L_VAL
120 ldr r1, =CONFIG_SYS_CS2U_VAL
124 ldr r1, =CONFIG_SYS_CS2L_VAL
128 ldr r1, =CONFIG_SYS_CS3U_VAL
132 ldr r1, =CONFIG_SYS_CS3L_VAL
136 ldr r1, =CONFIG_SYS_CS4U_VAL
140 ldr r1, =CONFIG_SYS_CS4L_VAL
144 ldr r1, =CONFIG_SYS_CS5U_VAL
148 ldr r1, =CONFIG_SYS_CS5L_VAL
154 ldr r1, =PRECHARGE_CMD
158 ldr r1, =0x0 /* Issue Precharge all Command */
162 ldr r1, =AUTOREFRESH_CMD
166 ldr r1, =0x0 /* Issue AutoRefresh Command */
180 ldr r0, =0x08223000 /* CAS Latency 2 */
181 ldr r1, =0x0 /* Issue Mode Register Command, Burst Length = 8 */
185 ldr r1, =0x810a8200 /* Set to Normal Mode CAS 2 */