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Diffstat (limited to 'cpu/bf533/start.S')
| -rw-r--r-- | cpu/bf533/start.S | 435 |
1 files changed, 435 insertions, 0 deletions
diff --git a/cpu/bf533/start.S b/cpu/bf533/start.S new file mode 100644 index 0000000..7414d88 --- /dev/null +++ b/cpu/bf533/start.S @@ -0,0 +1,435 @@ +/* + * 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; |