u-boot/cpu/bf533/start.S
2006-03-12 02:55:22 +01:00

435 lines
10 KiB
ArmAsm

/*
* U-boot - start.S Startup file of u-boot for BF533
*
* Copyright (c) 2005 blackfin.uclinux.org
*
* This file is based on head.S
* Copyright (c) 2003 Metrowerks/Motorola
* Copyright (C) 1998 D. Jeff Dionne <jeff@ryeham.ee.ryerson.ca>,
* Kenneth Albanowski <kjahds@kjahds.com>,
* The Silver Hammer Group, Ltd.
* (c) 1995, Dionne & Associates
* (c) 1995, DKG Display Tech.
*
* 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
*/
/*
* Note: A change in this file subsequently requires a change in
* board/$(board_name)/config.mk for a valid u-boot.bin
*/
#define ASSEMBLY
#include <linux/config.h>
#include <asm/blackfin.h>
#include <config.h>
#include <asm/mem_init.h>
#if (CONFIG_CCLK_DIV == 1)
#define CONFIG_CCLK_ACT_DIV CCLK_DIV1
#endif
#if (CONFIG_CCLK_DIV == 2)
#define CONFIG_CCLK_ACT_DIV CCLK_DIV2
#endif
#if (CONFIG_CCLK_DIV == 4)
#define CONFIG_CCLK_ACT_DIV CCLK_DIV4
#endif
#if (CONFIG_CCLK_DIV == 8)
#define CONFIG_CCLK_ACT_DIV CCLK_DIV8
#endif
#ifndef CONFIG_CCLK_ACT_DIV
#define CONFIG_CCLK_ACT_DIV CONFIG_CCLK_DIV_not_defined_properly
#endif
.global _stext;
.global __bss_start;
.global start;
.global _start;
.global _rambase;
.global _ramstart;
.global _ramend;
.global _bf533_data_dest;
.global _bf533_data_size;
.global edata;
.global _initialize;
.global _exit;
.global flashdataend;
.text
_start:
start:
_stext:
R0 = 0x30;
SYSCFG = R0;
SSYNC;
/* As per HW reference manual DAG registers,
* DATA and Address resgister shall be zero'd
* in initialization, after a reset state
*/
r1 = 0; /* Data registers zero'd */
r2 = 0;
r3 = 0;
r4 = 0;
r5 = 0;
r6 = 0;
r7 = 0;
p0 = 0; /* Address registers zero'd */
p1 = 0;
p2 = 0;
p3 = 0;
p4 = 0;
p5 = 0;
i0 = 0; /* DAG Registers zero'd */
i1 = 0;
i2 = 0;
i3 = 0;
m0 = 0;
m1 = 0;
m3 = 0;
m3 = 0;
l0 = 0;
l1 = 0;
l2 = 0;
l3 = 0;
b0 = 0;
b1 = 0;
b2 = 0;
b3 = 0;
/* Set loop counters to zero, to make sure that
* hw loops are disabled.
*/
lc0 = 0;
lc1 = 0;
SSYNC;
/* Check soft reset status */
p0.h = SWRST >> 16;
p0.l = SWRST & 0xFFFF;
r0.l = w[p0];
cc = bittst(r0, 15);
if !cc jump no_soft_reset;
/* Clear Soft reset */
r0 = 0x0000;
w[p0] = r0;
ssync;
no_soft_reset:
nop;
/* Clear EVT registers */
p0.h = (EVT_EMULATION_ADDR >> 16);
p0.l = (EVT_EMULATION_ADDR & 0xFFFF);
p0 += 8;
p1 = 14;
r1 = 0;
LSETUP(4,4) lc0 = p1;
[ p0 ++ ] = r1;
/*
* Set PLL_CTL
* - [14:09] = MSEL[5:0] : CLKIN / VCO multiplication factors
* - [8] = BYPASS : BYPASS the PLL, run CLKIN into CCLK/SCLK
* - [7] = output delay (add 200ps of delay to mem signals)
* - [6] = input delay (add 200ps of input delay to mem signals)
* - [5] = PDWN : 1=All Clocks off
* - [3] = STOPCK : 1=Core Clock off
* - [1] = PLL_OFF : 1=Disable Power to PLL
* - [0] = DF : 1=Pass CLKIN/2 to PLL / 0=Pass CLKIN to PLL
* all other bits set to zero
*/
r0 = CONFIG_VCO_MULT; /* Load the VCO multiplier */
r0 = r0 << 9; /* Shift it over */
r1 = CONFIG_CLKIN_HALF; /* Do we need to divide CLKIN by 2? */
r0 = r1 | r0;
r1 = CONFIG_PLL_BYPASS; /* Bypass the PLL? */
r1 = r1 << 8; /* Shift it over */
r0 = r1 | r0; /* add them all together */
p0.h = (PLL_CTL >> 16);
p0.l = (PLL_CTL & 0xFFFF); /* Load the address */
cli r2; /* Disable interrupts */
w[p0] = r0; /* Set the value */
idle; /* Wait for the PLL to stablize */
sti r2; /* Enable interrupts */
ssync;
/*
* Turn on the CYCLES COUNTER
*/
r2 = SYSCFG;
BITSET (r2,1);
SYSCFG = r2;
/* Configure SCLK & CCLK Dividers */
r0 = CONFIG_CCLK_ACT_DIV | CONFIG_SCLK_DIV;
p0.h = (PLL_DIV >> 16);
p0.l = (PLL_DIV & 0xFFFF);
w[p0] = r0;
ssync;
wait_for_pll_stab:
p0.h = (PLL_STAT >> 16);
p0.l = (PLL_STAT & 0xFFFF);
r0.l = w[p0];
cc = bittst(r0,5);
if !cc jump wait_for_pll_stab;
/* Configure SDRAM if SDRAM is already not enabled */
p0.l = (EBIU_SDSTAT & 0xFFFF);
p0.h = (EBIU_SDSTAT >> 16);
r0.l = w[p0];
cc = bittst(r0, 3);
if !cc jump skip_sdram_enable;
/* SDRAM initialization */
p0.l = (EBIU_SDGCTL & 0xFFFF);
p0.h = (EBIU_SDGCTL >> 16); /* SDRAM Memory Global Control Register */
r0.h = (mem_SDGCTL >> 16);
r0.l = (mem_SDGCTL & 0xFFFF);
[p0] = r0;
ssync;
p0.l = (EBIU_SDBCTL & 0xFFFF);
p0.h = (EBIU_SDBCTL >> 16); /* SDRAM Memory Bank Control Register */
r0 = mem_SDBCTL;
w[p0] = r0.l;
ssync;
p0.l = (EBIU_SDRRC & 0xFFFF);
p0.h = (EBIU_SDRRC >> 16); /* SDRAM Refresh Rate Control Register */
r0 = mem_SDRRC;
w[p0] = r0.l;
ssync;
skip_sdram_enable:
nop;
#ifndef CFG_NO_FLASH
/* relocate into to RAM */
p1.l = (CFG_FLASH_BASE & 0xffff);
p1.h = (CFG_FLASH_BASE >> 16);
p2.l = (CFG_MONITOR_BASE & 0xffff);
p2.h = (CFG_MONITOR_BASE >> 16);
r0.l = (CFG_MONITOR_LEN & 0xffff);
r0.h = (CFG_MONITOR_LEN >> 16);
loop1:
r1 = [p1];
[p2] = r1;
p3=0x4;
p1=p1+p3;
p2=p2+p3;
r2=0x4;
r0=r0-r2;
cc=r0==0x0;
if !cc jump loop1;
#endif
/*
* configure STACK
*/
r0.h = (CONFIG_STACKBASE >> 16);
r0.l = (CONFIG_STACKBASE & 0xFFFF);
sp = r0;
fp = sp;
/*
* This next section keeps the processor in supervisor mode
* during kernel boot. Switches to user mode at end of boot.
* See page 3-9 of Hardware Reference manual for documentation.
*/
/* To keep ourselves in the supervisor mode */
p0.l = (EVT_IVG15_ADDR & 0xFFFF);
p0.h = (EVT_IVG15_ADDR >> 16);
p1.l = _real_start;
p1.h = _real_start;
[p0] = p1;
p0.l = (IMASK & 0xFFFF);
p0.h = (IMASK >> 16);
r0 = IVG15_POS;
[p0] = r0;
raise 15;
p0.l = WAIT_HERE;
p0.h = WAIT_HERE;
reti = p0;
rti;
WAIT_HERE:
jump WAIT_HERE;
.global _real_start;
_real_start:
[ -- sp ] = reti;
#ifdef CONFIG_EZKIT533
p0.l = (WDOG_CTL & 0xFFFF);
p0.h = (WDOG_CTL >> 16);
r0 = WATCHDOG_DISABLE(z);
w[p0] = r0;
#endif
/* Code for initializing Async mem banks */
p2.h = (EBIU_AMBCTL1 >> 16);
p2.l = (EBIU_AMBCTL1 & 0xFFFF);
r0.h = (AMBCTL1VAL >> 16);
r0.l = (AMBCTL1VAL & 0xFFFF);
[p2] = r0;
ssync;
p2.h = (EBIU_AMBCTL0 >> 16);
p2.l = (EBIU_AMBCTL0 & 0xFFFF);
r0.h = (AMBCTL0VAL >> 16);
r0.l = (AMBCTL0VAL & 0xFFFF);
[p2] = r0;
ssync;
p2.h = (EBIU_AMGCTL >> 16);
p2.l = (EBIU_AMGCTL & 0xffff);
r0 = AMGCTLVAL;
w[p2] = r0;
ssync;
/* DMA reset code to Hi of L1 SRAM */
copy:
P1.H = hi(SYSMMR_BASE); /* P1 Points to the beginning of SYSTEM MMR Space */
P1.L = lo(SYSMMR_BASE);
R0.H = reset_start; /* Source Address (high) */
R0.L = reset_start; /* Source Address (low) */
R1.H = reset_end;
R1.L = reset_end;
R2 = R1 - R0; /* Count */
R1.H = hi(L1_ISRAM); /* Destination Address (high) */
R1.L = lo(L1_ISRAM); /* Destination Address (low) */
R3.L = DMAEN; /* Source DMAConfig Value (8-bit words) */
R4.L = (DI_EN | WNR | DMAEN); /* Destination DMAConfig Value (8-bit words) */
DMA:
R6 = 0x1 (Z);
W[P1+OFFSET_(MDMA_S0_X_MODIFY)] = R6; /* Source Modify = 1 */
W[P1+OFFSET_(MDMA_D0_X_MODIFY)] = R6; /* Destination Modify = 1 */
[P1+OFFSET_(MDMA_S0_START_ADDR)] = R0; /* Set Source Base Address */
W[P1+OFFSET_(MDMA_S0_X_COUNT)] = R2; /* Set Source Count */
/* Set Source DMAConfig = DMA Enable,
Memory Read, 8-Bit Transfers, 1-D DMA, Flow - Stop */
W[P1+OFFSET_(MDMA_S0_CONFIG)] = R3;
[P1+OFFSET_(MDMA_D0_START_ADDR)] = R1; /* Set Destination Base Address */
W[P1+OFFSET_(MDMA_D0_X_COUNT)] = R2; /* Set Destination Count */
/* Set Destination DMAConfig = DMA Enable,
Memory Write, 8-Bit Transfers, 1-D DMA, Flow - Stop, IOC */
W[P1+OFFSET_(MDMA_D0_CONFIG)] = R4;
IDLE; /* Wait for DMA to Complete */
R0 = 0x1;
W[P1+OFFSET_(MDMA_D0_IRQ_STATUS)] = R0; /* Write 1 to clear DMA interrupt */
/* DMA reset code to DATA BANK A which uses this port
* to avoid following problem
* " Data from a Data Cache fill can be corrupoted after or during
* instruction DMA if certain core stalls exist"
*/
copy_as_data:
R0.H = reset_start; /* Source Address (high) */
R0.L = reset_start; /* Source Address (low) */
R1.H = reset_end;
R1.L = reset_end;
R2 = R1 - R0; /* Count */
R1.H = hi(DATA_BANKA_SRAM); /* Destination Address (high) */
R1.L = lo(DATA_BANKA_SRAM); /* Destination Address (low) */
R3.L = DMAEN; /* Source DMAConfig Value (8-bit words) */
R4.L = (DI_EN | WNR | DMAEN); /* Destination DMAConfig Value (8-bit words) */
DMA_DATA:
R6 = 0x1 (Z);
W[P1+OFFSET_(MDMA_S0_X_MODIFY)] = R6; /* Source Modify = 1 */
W[P1+OFFSET_(MDMA_D0_X_MODIFY)] = R6; /* Destination Modify = 1 */
[P1+OFFSET_(MDMA_S0_START_ADDR)] = R0; /* Set Source Base Address */
W[P1+OFFSET_(MDMA_S0_X_COUNT)] = R2; /* Set Source Count */
/* Set Source DMAConfig = DMA Enable,
Memory Read, 8-Bit Transfers, 1-D DMA, Flow - Stop */
W[P1+OFFSET_(MDMA_S0_CONFIG)] = R3;
[P1+OFFSET_(MDMA_D0_START_ADDR)] = R1; /* Set Destination Base Address */
W[P1+OFFSET_(MDMA_D0_X_COUNT)] = R2; /* Set Destination Count */
/* Set Destination DMAConfig = DMA Enable,
Memory Write, 8-Bit Transfers, 1-D DMA, Flow - Stop, IOC */
W[P1+OFFSET_(MDMA_D0_CONFIG)] = R4;
IDLE; /* Wait for DMA to Complete */
R0 = 0x1;
W[P1+OFFSET_(MDMA_D0_IRQ_STATUS)] = R0; /* Write 1 to clear DMA interrupt */
copy_end: nop;
/* Initialize BSS Section with 0 s */
p1.l = __bss_start;
p1.h = __bss_start;
p2.l = _end;
p2.h = _end;
r1 = p1;
r2 = p2;
r3 = r2 - r1;
r3 = r3 >> 2;
p3 = r3;
lsetup (_clear_bss, _clear_bss_end ) lc1 = p3;
CC = p2<=p1;
if CC jump _clear_bss_skip;
r0 = 0;
_clear_bss:
_clear_bss_end:
[p1++] = r0;
_clear_bss_skip:
p0.l = _start1;
p0.h = _start1;
jump (p0);
reset_start:
p0.h = WDOG_CNT >> 16;
p0.l = WDOG_CNT & 0xffff;
r0 = 0x0010;
w[p0] = r0;
p0.h = WDOG_CTL >> 16;
p0.l = WDOG_CTL & 0xffff;
r0 = 0x0000;
w[p0] = r0;
reset_wait:
jump reset_wait;
reset_end: nop;
_exit:
jump.s _exit;