diff options
Diffstat (limited to 'board/dbau1x00/lowlevel_init.S')
| -rw-r--r-- | board/dbau1x00/lowlevel_init.S | 587 |
1 files changed, 587 insertions, 0 deletions
diff --git a/board/dbau1x00/lowlevel_init.S b/board/dbau1x00/lowlevel_init.S new file mode 100644 index 0000000..7afd584 --- /dev/null +++ b/board/dbau1x00/lowlevel_init.S @@ -0,0 +1,587 @@ +/* Memory sub-system initialization code */ + +#include <config.h> +#include <version.h> +#include <asm/regdef.h> +#include <asm/au1x00.h> +#include <asm/mipsregs.h> + +#define AU1500_SYS_ADDR 0xB1900000 +#define sys_endian 0x0038 +#define CP0_Config0 $16 +#define CPU_SCALE ((CFG_MHZ) / 12) /* CPU clock is a multiple of 12 MHz */ +#define MEM_1MS ((CFG_MHZ) * 1000) + + .text + .set noreorder + .set mips32 + + .globl lowlevel_init +lowlevel_init: + /* + * Step 1) Establish CPU endian mode. + * Db1500-specific: + * Switch S1.1 Off(bit7 reads 1) is Little Endian + * Switch S1.1 On (bit7 reads 0) is Big Endian + */ +#ifdef CONFIG_DBAU1550 + li t0, MEM_STCFG2 + li t1, 0x00000040 + sw t1, 0(t0) + + li t0, MEM_STTIME2 + li t1, 0x22080a20 + sw t1, 0(t0) + + li t0, MEM_STADDR2 + li t1, 0x10c03f00 + sw t1, 0(t0) +#else + li t0, MEM_STCFG1 + li t1, 0x00000080 + sw t1, 0(t0) + + li t0, MEM_STTIME1 + li t1, 0x22080a20 + sw t1, 0(t0) + + li t0, MEM_STADDR1 + li t1, 0x10c03f00 + sw t1, 0(t0) +#endif + + li t0, DB1XX0_BCSR_ADDR + lw t1,8(t0) + andi t1,t1,0x80 + beq zero,t1,big_endian + nop +little_endian: + + /* Change Au1 core to little endian */ + li t0, AU1500_SYS_ADDR + li t1, 1 + sw t1, sys_endian(t0) + mfc0 t2, CP0_CONFIG + mtc0 t2, CP0_CONFIG + nop + nop + + /* Big Endian is default so nothing to do but fall through */ + +big_endian: + + /* + * Step 2) Establish Status Register + * (set BEV, clear ERL, clear EXL, clear IE) + */ + li t1, 0x00400000 + mtc0 t1, CP0_STATUS + + /* + * Step 3) Establish CP0 Config0 + * (set OD, set K0=3) + */ + li t1, 0x00080003 + mtc0 t1, CP0_CONFIG + + /* + * Step 4) Disable Watchpoint facilities + */ + li t1, 0x00000000 + mtc0 t1, CP0_WATCHLO + mtc0 t1, CP0_IWATCHLO + /* + * Step 5) Disable the performance counters + */ + mtc0 zero, CP0_PERFORMANCE + nop + + /* + * Step 6) Establish EJTAG Debug register + */ + mtc0 zero, CP0_DEBUG + nop + + /* + * Step 7) Establish Cause + * (set IV bit) + */ + li t1, 0x00800000 + mtc0 t1, CP0_CAUSE + + /* Establish Wired (and Random) */ + mtc0 zero, CP0_WIRED + nop + +#ifdef CONFIG_DBAU1550 + /* No workaround if running from ram */ + lui t0, 0xffc0 + lui t3, 0xbfc0 + and t1, ra, t0 + bne t1, t3, noCacheJump + nop + + /*** From AMD YAMON ***/ + /* + * Step 8) Initialize the caches + */ + li t0, (16*1024) + li t1, 32 + li t2, 0x80000000 + addu t3, t0, t2 +cacheloop: + cache 0, 0(t2) + cache 1, 0(t2) + addu t2, t1 + bne t2, t3, cacheloop + nop + + /* Save return address */ + move t3, ra + + /* Run from cacheable space now */ + bal cachehere + nop +cachehere: + li t1, ~0x20000000 /* convert to KSEG0 */ + and t0, ra, t1 + addi t0, 5*4 /* 5 insns beyond cachehere */ + jr t0 + nop + + /* Restore return address */ + move ra, t3 + + /* + * Step 9) Initialize the TLB + */ + li t0, 0 # index value + li t1, 0x00000000 # entryhi value + li t2, 32 # 32 entries + +tlbloop: + /* Probe TLB for matching EntryHi */ + mtc0 t1, CP0_ENTRYHI + tlbp + nop + + /* Examine Index[P], 1=no matching entry */ + mfc0 t3, CP0_INDEX + li t4, 0x80000000 + and t3, t4, t3 + addiu t1, t1, 1 # increment t1 (asid) + beq zero, t3, tlbloop + nop + + /* Initialize the TLB entry */ + mtc0 t0, CP0_INDEX + mtc0 zero, CP0_ENTRYLO0 + mtc0 zero, CP0_ENTRYLO1 + mtc0 zero, CP0_PAGEMASK + tlbwi + + /* Do it again */ + addiu t0, t0, 1 + bne t0, t2, tlbloop + nop + + /* First setup pll:s to make serial work ok */ + /* We have a 12 MHz crystal */ + li t0, SYS_CPUPLL + li t1, CPU_SCALE /* CPU clock */ + sw t1, 0(t0) + sync + nop + nop + + /* wait 1mS for clocks to settle */ + li t1, MEM_1MS +1: add t1, -1 + bne t1, zero, 1b + nop + /* Setup AUX PLL */ + li t0, SYS_AUXPLL + li t1, 0x20 /* 96 MHz */ + sw t1, 0(t0) /* aux pll */ + sync + + /* Static memory controller */ + /* RCE0 - can not change while fetching, do so from icache */ + move t2, ra /* Store return address */ + bal getAddr + nop + +getAddr: + move t1, ra + move ra, t2 /* Move return addess back */ + + cache 0x14,0(t1) + cache 0x14,32(t1) + /*** /From YAMON ***/ + +noCacheJump: +#endif /* CONFIG_DBAU1550 */ + +#ifdef CONFIG_DBAU1550 + li t0, MEM_STTIME0 + li t1, 0x040181D7 + sw t1, 0(t0) + + /* RCE0 AMD MirrorBit Flash (?) */ + li t0, MEM_STCFG0 + li t1, 0x00000003 + sw t1, 0(t0) + + li t0, MEM_STADDR0 + li t1, 0x11803E00 + sw t1, 0(t0) +#else /* CONFIG_DBAU1550 */ + li t0, MEM_STTIME0 + li t1, 0x00014C0F + sw t1, 0(t0) + + /* RCE0 AMD 29LV640M MirrorBit Flash */ + li t0, MEM_STCFG0 + li t1, 0x00000013 + sw t1, 0(t0) + + li t0, MEM_STADDR0 + li t1, 0x11E03F80 + sw t1, 0(t0) +#endif /* CONFIG_DBAU1550 */ + + /* RCE1 CPLD Board Logic */ + li t0, MEM_STCFG1 + li t1, 0x00000080 + sw t1, 0(t0) + + li t0, MEM_STTIME1 + li t1, 0x22080a20 + sw t1, 0(t0) + + li t0, MEM_STADDR1 + li t1, 0x10c03f00 + sw t1, 0(t0) + +#ifdef CONFIG_DBAU1550 + /* RCE2 CPLD Board Logic */ + li t0, MEM_STCFG2 + li t1, 0x00000040 + sw t1, 0(t0) + + li t0, MEM_STTIME2 + li t1, 0x22080a20 + sw t1, 0(t0) + + li t0, MEM_STADDR2 + li t1, 0x10c03f00 + sw t1, 0(t0) +#else + li t0, MEM_STCFG2 + li t1, 0x00000000 + sw t1, 0(t0) + + li t0, MEM_STTIME2 + li t1, 0x00000000 + sw t1, 0(t0) + + li t0, MEM_STADDR2 + li t1, 0x00000000 + sw t1, 0(t0) +#endif + + /* RCE3 PCMCIA 250ns */ + li t0, MEM_STCFG3 + li t1, 0x00000002 + sw t1, 0(t0) + + li t0, MEM_STTIME3 + li t1, 0x280E3E07 + sw t1, 0(t0) + + li t0, MEM_STADDR3 + li t1, 0x10000000 + sw t1, 0(t0) + + sync + + /* Set peripherals to a known state */ + li t0, IC0_CFG0CLR + li t1, 0xFFFFFFFF + sw t1, 0(t0) + + li t0, IC0_CFG0CLR + sw t1, 0(t0) + + li t0, IC0_CFG1CLR + sw t1, 0(t0) + + li t0, IC0_CFG2CLR + sw t1, 0(t0) + + li t0, IC0_SRCSET + sw t1, 0(t0) + + li t0, IC0_ASSIGNSET + sw t1, 0(t0) + + li t0, IC0_WAKECLR + sw t1, 0(t0) + + li t0, IC0_RISINGCLR + sw t1, 0(t0) + + li t0, IC0_FALLINGCLR + sw t1, 0(t0) + + li t0, IC0_TESTBIT + li t1, 0x00000000 + sw t1, 0(t0) + sync + + li t0, IC1_CFG0CLR + li t1, 0xFFFFFFFF + sw t1, 0(t0) + + li t0, IC1_CFG0CLR + sw t1, 0(t0) + + li t0, IC1_CFG1CLR + sw t1, 0(t0) + + li t0, IC1_CFG2CLR + sw t1, 0(t0) + + li t0, IC1_SRCSET + sw t1, 0(t0) + + li t0, IC1_ASSIGNSET + sw t1, 0(t0) + + li t0, IC1_WAKECLR + sw t1, 0(t0) + + li t0, IC1_RISINGCLR + sw t1, 0(t0) + + li t0, IC1_FALLINGCLR + sw t1, 0(t0) + + li t0, IC1_TESTBIT + li t1, 0x00000000 + sw t1, 0(t0) + sync + + li t0, SYS_FREQCTRL0 + li t1, 0x00000000 + sw t1, 0(t0) + + li t0, SYS_FREQCTRL1 + li t1, 0x00000000 + sw t1, 0(t0) + + li t0, SYS_CLKSRC + li t1, 0x00000000 + sw t1, 0(t0) + + li t0, SYS_PININPUTEN + li t1, 0x00000000 + sw t1, 0(t0) + sync + + li t0, 0xB1100100 + li t1, 0x00000000 + sw t1, 0(t0) + + li t0, 0xB1400100 + li t1, 0x00000000 + sw t1, 0(t0) + + + li t0, SYS_WAKEMSK + li t1, 0x00000000 + sw t1, 0(t0) + + li t0, SYS_WAKESRC + li t1, 0x00000000 + sw t1, 0(t0) + + /* wait 1mS before setup */ + li t1, MEM_1MS +1: add t1, -1 + bne t1, zero, 1b + nop + +#ifdef CONFIG_DBAU1550 +/* SDCS 0,1,2 DDR SDRAM */ + li t0, MEM_SDMODE0 + li t1, 0x04276221 + sw t1, 0(t0) + + li t0, MEM_SDMODE1 + li t1, 0x04276221 + sw t1, 0(t0) + + li t0, MEM_SDMODE2 + li t1, 0x04276221 + sw t1, 0(t0) + + li t0, MEM_SDADDR0 + li t1, 0xe21003f0 + sw t1, 0(t0) + + li t0, MEM_SDADDR1 + li t1, 0xe21043f0 + sw t1, 0(t0) + + li t0, MEM_SDADDR2 + li t1, 0xe21083f0 + sw t1, 0(t0) + + sync + + li t0, MEM_SDCONFIGA + li t1, 0x9030060a /* Program refresh - disabled */ + sw t1, 0(t0) + sync + + li t0, MEM_SDCONFIGB + li t1, 0x00028000 + sw t1, 0(t0) + sync + + li t0, MEM_SDPRECMD /* Precharge all */ + li t1, 0 + sw t1, 0(t0) + sync + + li t0, MEM_SDWRMD0 + li t1, 0x40000000 + sw t1, 0(t0) + sync + + li t0, MEM_SDWRMD1 + li t1, 0x40000000 + sw t1, 0(t0) + sync + + li t0, MEM_SDWRMD2 + li t1, 0x40000000 + sw t1, 0(t0) + sync + + li t0, MEM_SDWRMD0 + li t1, 0x00000063 + sw t1, 0(t0) + sync + + li t0, MEM_SDWRMD1 + li t1, 0x00000063 + sw t1, 0(t0) + sync + + li t0, MEM_SDWRMD2 + li t1, 0x00000063 + sw t1, 0(t0) + sync + + li t0, MEM_SDPRECMD /* Precharge all */ + sw zero, 0(t0) + sync + + /* Issue 2 autoref */ + li t0, MEM_SDAUTOREF + sw zero, 0(t0) + sync + + li t0, MEM_SDAUTOREF + sw zero, 0(t0) + sync + + /* Enable refresh */ + li t0, MEM_SDCONFIGA + li t1, 0x9830060a /* Program refresh - enabled */ + sw t1, 0(t0) + sync + +#else /* CONFIG_DBAU1550 */ +/* SDCS 0,1 SDRAM */ + li t0, MEM_SDMODE0 + li t1, 0x005522AA + sw t1, 0(t0) + + li t0, MEM_SDMODE1 + li t1, 0x005522AA + sw t1, 0(t0) + + li t0, MEM_SDMODE2 + li t1, 0x00000000 + sw t1, 0(t0) + + li t0, MEM_SDADDR0 + li t1, 0x001003F8 + sw t1, 0(t0) + + + li t0, MEM_SDADDR1 + li t1, 0x001023F8 + sw t1, 0(t0) + + li t0, MEM_SDADDR2 + li t1, 0x00000000 + sw t1, 0(t0) + + sync + + li t0, MEM_SDREFCFG + li t1, 0x64000C24 /* Disable */ + sw t1, 0(t0) + sync + + li t0, MEM_SDPRECMD + sw zero, 0(t0) + sync + + li t0, MEM_SDAUTOREF + sw zero, 0(t0) + sync + sw zero, 0(t0) + sync + + li t0, MEM_SDREFCFG + li t1, 0x66000C24 /* Enable */ + sw t1, 0(t0) + sync + + li t0, MEM_SDWRMD0 + li t1, 0x00000033 + sw t1, 0(t0) + sync + + li t0, MEM_SDWRMD1 + li t1, 0x00000033 + sw t1, 0(t0) + sync + +#endif /* CONFIG_DBAU1550 */ + /* wait 1mS after setup */ + li t1, MEM_1MS +1: add t1, -1 + bne t1, zero, 1b + nop + + li t0, SYS_PINFUNC + li t1, 0x00008080 + sw t1, 0(t0) + + li t0, SYS_TRIOUTCLR + li t1, 0x00001FFF + sw t1, 0(t0) + + li t0, SYS_OUTPUTCLR + li t1, 0x00008000 + sw t1, 0(t0) + sync + + j ra + nop |