sysinit.c

这是ARM7上常用的bios-lt74的愿代码包

#include "board.h"
#include "utils.h"
#include "bios.h"

static inline void reset_registers(void);

/*
 * Caculate system registers
 */

int sys_init(struct system_table_struct *system_table, unsigned long rom_base, unsigned dram_base)
{
	struct sys_regs_struct sys_regs;
	unsigned long base;
	unsigned long r;
	int i;

	sys_regs.extdbwth = 0;
	for (i = 0; i < 6; i++)
		sys_regs.extdbwth |= (system_table->rom_table[i].width) << (i * 2);
	for (i = 0; i < 4; i++)
		sys_regs.extdbwth |= (system_table->dram_table[i].width) << (i * 2 + 12);
	for (i = 0; i < 4; i++)
		sys_regs.extdbwth |= (system_table->ext_table[i].width) << (i * 2 + 20);

	base = rom_base;
	for (i = 0; i < 6; i++) {
		sys_regs.romcon[i] = (system_table->rom_table[i].flag & ~0x3ffffc00) |
			(((base + system_table->rom_table[i].size) & 0x03ff0000) << 4) |
			((base & 0x03ff0000) >> 6);
		base += system_table->rom_table[i].size;
	}

	base = dram_base;
	for (i = 0; i < 4; i++) {
		sys_regs.dramcon[i] = (system_table->dram_table[i].flag & ~0x3ffffc00) |
			(((base + system_table->dram_table[i].size) & 0x03ff0000) << 4) |
			((base & 0x03ff0000) >> 6);
		base += system_table->dram_table[i].size;
	}

	sys_regs.refextcon = system_table->dram_table[0].refresh;

	outl(sys_regs.extdbwth, EXTDBWTH);
	outl(sys_regs.romcon[0], ROMCON0);
	outl(sys_regs.romcon[1], ROMCON1);
	outl(sys_regs.romcon[2], ROMCON2);
	outl(sys_regs.romcon[3], ROMCON3);
	outl(sys_regs.romcon[4], ROMCON4);
	outl(sys_regs.romcon[5], ROMCON5);
	outl(sys_regs.dramcon[0], DRAMCON0);
	outl(sys_regs.dramcon[1], DRAMCON1);
	outl(sys_regs.dramcon[2], DRAMCON2);
	outl(sys_regs.dramcon[3], DRAMCON3);
	outl(sys_regs.refextcon, REFEXTCON);

	r = (system_table->ext_table[0].flag & 0xffff) |
		((system_table->ext_table[1].flag & 0xffff) << 16);
	outl(r, EXTACON0);
	r = (system_table->ext_table[2].flag & 0xffff) |
		((system_table->ext_table[3].flag & 0xffff) << 16);
	outl(r, EXTACON1);

	outl(system_table->iop.iopmod, IOPMOD);
	outl(system_table->iop.iopcon, IOPCON);
	outl(system_table->iop.iopdata, IOPDATA);

	reset_registers();
	return 0;
}

/*
 * This function exists for supporting soft-reset
 * of S3C4510B. However, some readonly registers
 * perhaps don't contail "reset values" after this
 * function, so it is still possiable that you have
 * some dirty registers after a soft-reset. So make
 * sure your application can handl these registers.
 *
 * These registers are noted by double slash below.
 */
static inline void reset_registers(void) {
	/* Ethernet */
	outl(0, BDMATXCON);
	outl(0, BDMARXCON);
	outl(0xffffffff, BDMATXPTR);
	outl(0xffffffff, BDMARXPTR);
	outl(0, BDMASTAT);
	outl(0, MACON);
	outl(0, CAMCON);
	outl(0, MACTXCON);
	outl(0, MACTXSTAT);
	outl(0, MACRXCON);
	outl(0, MACRXSTAT);
	outl(0, STADATA);
	outl(0x00006000, STACON);
	outl(0, CAMEN);
	outl(0, EMISSCNT);
//	outl(0, EPZCNT);
//	outl(0, ERMPZCNT);	
//	outl(0, ETXSTAT);	

	/* HDLC channel A */
	outl(0, HMODE_A);
	outl(0, HCON_A);
	outl(0, HSTAT_A);
	outl(0, HINTEN_A);
//	outl(0, HRXFIFO_A);
	outl(0, HBRGTC_A);
	outl(0, HPRMB_A);
	outl(0, HSAR0_A);
	outl(0, HSAR1_A);
	outl(0, HSAR2_A);
	outl(0, HSAR3_A);
	outl(0, HMASK_A);
	outl(0xffffffff, DMATXPTR_A);
	outl(0xffffffff, DMARXPTR_A);
	outl(0, HMFLR_A);
	outl(0, HRBSR_A);

	/* HDLC channel B */
	outl(0, HMODE_B);
	outl(0, HCON_B);
	outl(0, HSTAT_B);
	outl(0, HINTEN_B);
//	outl(0, HRXFIFO_B);
	outl(0, HBRGTC_B);
	outl(0, HPRMB_B);
	outl(0, HSAR0_B);
	outl(0, HSAR1_B);
	outl(0, HSAR2_B);
	outl(0, HSAR3_B);
	outl(0, HMASK_B);
	outl(0xffffffff, DMATXPTR_B);
	outl(0xffffffff, DMARXPTR_B);
	outl(0, HMFLR_B);
	outl(0, HRBSR_B);

	/* Interrupt Controller */
	outl(0, INTMOD);
	outl(0, INTPND);
	outl(0x003fffff, INTMSK);
	outl(0x03020100, INTPRI0);
	outl(0x07060504, INTPRI1);
	outl(0x0b0a0908, INTPRI2);
	outl(0x0f0e0d0c, INTPRI3);
	outl(0x13121110, INTPRI4);
	outl(0x00000014, INTPRI5);
//	outl(0x00000054, INTOFFSET);
//	outl(0x00000054, INTOSET_FIQ);
//	outl(0x00000054, INTOSET_IRQ);

	/* I2C Bus */
	outl(0, IICCON);
	outl(0, IICPS);
	outl(0, IICCOUNT);

	/* GDMA */
	outl(0, GDMACON0);
	outl(0, GDMACON1);

	/* Timers */
	outl(0, TMOD);
	outl(0, TDATA0);
	outl(0, TDATA1);
	outl(0xffffffff, TCNT0);
	outl(0xffffffff, TCNT1);
}