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+/*
+ * Board specific setup info
+ *
+ * (C) Copyright 2004
+ * Texas Instruments, <www.ti.com>
+ * Richard Woodruff <r-woodruff2@ti.com>
+ *
+ * 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 <config.h>
+#include <version.h>
+#include <asm/arch/omap2420.h>
+#include <asm/arch/mem.h>
+#include <asm/arch/clocks.h>
+
+_TEXT_BASE:
+ .word TEXT_BASE /* sdram load addr from config.mk */
+
+/**************************************************************************
+ * cpy_clk_code: relocates clock code into SRAM where its safer to execute
+ * R1 = SRAM destination address.
+ *************************************************************************/
+.global cpy_clk_code
+ cpy_clk_code:
+ /* Copy DPLL code into SRAM */
+ adr r0, go_to_speed /* get addr of clock setting code */
+ mov r2, #384 /* r2 size to copy (div by 32 bytes) */
+ mov r1, r1 /* r1 <- dest address (passed in) */
+ add r2, r2, r0 /* r2 <- source end address */
+next2:
+ ldmia r0!, {r3-r10} /* copy from source address [r0] */
+ stmia r1!, {r3-r10} /* copy to target address [r1] */
+ cmp r0, r2 /* until source end address [r2] */
+ bne next2
+ mov pc, lr /* back to caller */
+
+/* ****************************************************************************
+ * go_to_speed: -Moves to bypass, -Commits clock dividers, -puts dpll at speed
+ * -executed from SRAM.
+ * R0 = PRCM_CLKCFG_CTRL - addr of valid reg
+ * R1 = CM_CLKEN_PLL - addr dpll ctlr reg
+ * R2 = dpll value
+ * R3 = CM_IDLEST_CKGEN - addr dpll lock wait
+ ******************************************************************************/
+.global go_to_speed
+ go_to_speed:
+ sub sp, sp, #0x4 /* get some stack space */
+ str r4, [sp] /* save r4's value */
+
+ /* move into fast relock bypass */
+ ldr r8, pll_ctl_add
+ mov r4, #0x2
+ str r4, [r8]
+ ldr r4, pll_stat
+block:
+ ldr r8, [r4] /* wait for bypass to take effect */
+ and r8, r8, #0x3
+ cmp r8, #0x1
+ bne block
+
+ /* set new dpll dividers _after_ in bypass */
+ ldr r4, pll_div_add
+ ldr r8, pll_div_val
+ str r8, [r4]
+
+ /* now prepare GPMC (flash) for new dpll speed */
+ /* flash needs to be stable when we jump back to it */
+ ldr r4, cfg3_0_addr
+ ldr r8, cfg3_0_val
+ str r8, [r4]
+ ldr r4, cfg4_0_addr
+ ldr r8, cfg4_0_val
+ str r8, [r4]
+ ldr r4, cfg1_0_addr
+ ldr r8, [r4]
+ orr r8, r8, #0x3 /* up gpmc divider */
+ str r8, [r4]
+
+ /* setup to 2x loop though code. The first loop pre-loads the
+ * icache, the 2nd commits the prcm config, and locks the dpll
+ */
+ mov r4, #0x1000 /* spin spin spin */
+ mov r8, #0x4 /* first pass condition & set registers */
+ cmp r8, #0x4
+2:
+ ldrne r8, [r3] /* DPLL lock check */
+ and r8, r8, #0x7
+ cmp r8, #0x2
+ beq 4f
+3:
+ subeq r8, r8, #0x1
+ streq r8, [r0] /* commit dividers (2nd time) */
+ nop
+lloop1:
+ sub r4, r4, #0x1 /* Loop currently necessary else bad jumps */
+ nop
+ cmp r4, #0x0
+ bne lloop1
+ mov r4, #0x40000
+ cmp r8, #0x1
+ nop
+ streq r2, [r1] /* lock dpll (2nd time) */
+ nop
+lloop2:
+ sub r4, r4, #0x1 /* loop currently necessary else bad jumps */
+ nop
+ cmp r4, #0x0
+ bne lloop2
+ mov r4, #0x40000
+ cmp r8, #0x1
+ nop
+ ldreq r8, [r3] /* get lock condition for dpll */
+ cmp r8, #0x4 /* first time though? */
+ bne 2b
+ moveq r8, #0x2 /* set to dpll check condition. */
+ beq 3b /* if condition not true branch */
+4:
+ ldr r4, [sp]
+ add sp, sp, #0x4 /* return stack space */
+ mov pc, lr /* back to caller, locked */
+
+_go_to_speed: .word go_to_speed
+
+/* these constants need to be close for PIC code */
+cfg3_0_addr:
+ .word GPMC_CONFIG3_0
+cfg3_0_val:
+ .word H4_24XX_GPMC_CONFIG3_0
+cfg4_0_addr:
+ .word GPMC_CONFIG4_0
+cfg4_0_val:
+ .word H4_24XX_GPMC_CONFIG4_0
+cfg1_0_addr:
+ .word GPMC_CONFIG1_0
+pll_ctl_add:
+ .word CM_CLKEN_PLL
+pll_stat:
+ .word CM_IDLEST_CKGEN
+pll_div_add:
+ .word CM_CLKSEL1_PLL
+pll_div_val:
+ .word DPLL_VAL /* DPLL setting (300MHz default) */
+
+.globl lowlevel_init
+lowlevel_init:
+ ldr sp, SRAM_STACK
+ str ip, [sp] /* stash old link register */
+ mov ip, lr /* save link reg across call */
+ bl s_init /* go setup pll,mux,memory */
+ ldr ip, [sp] /* restore save ip */
+ mov lr, ip /* restore link reg */
+
+ /* map interrupt controller */
+ ldr r0, VAL_INTH_SETUP
+ mcr p15, 0, r0, c15, c2, 4
+
+ /* back to arch calling code */
+ mov pc, lr
+
+ /* the literal pools origin */
+ .ltorg
+
+REG_CONTROL_STATUS:
+ .word CONTROL_STATUS
+VAL_INTH_SETUP:
+ .word PERIFERAL_PORT_BASE
+SRAM_STACK:
+ .word LOW_LEVEL_SRAM_STACK