diff options
Diffstat (limited to 'board/pb1x00/lowlevel_init.S')
| -rw-r--r-- | board/pb1x00/lowlevel_init.S | 392 |
1 files changed, 392 insertions, 0 deletions
diff --git a/board/pb1x00/lowlevel_init.S b/board/pb1x00/lowlevel_init.S new file mode 100644 index 0000000..e851e2f --- /dev/null +++ b/board/pb1x00/lowlevel_init.S @@ -0,0 +1,392 @@ +/* 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 MEM_1MS ((396000000/1000000) * 1000) + + .text + .set noreorder + .set mips32 + + .globl lowlevel_init +lowlevel_init: + /* + * Step 1) Establish CPU endian mode. + * NOTE: A fair amount of code is necessary on the Pb1000 to + * obtain the value of Switch S8.1 which is used to determine + * endian at run-time. + */ + + /* RCE1 */ + li t0, MEM_STCFG1 + li t1, 0x00000083 + sw t1, 0(t0) + + li t0, MEM_STTIME1 + li t1, 0x33030A10 + sw t1, 0(t0) + + li t0, MEM_STADDR1 + li t1, 0x11803E40 + sw t1, 0(t0) + + /* Set DSTRB bits so switch will read correctly */ + li t1, 0xBE00000C + lw t2, 0(t1) + or t2, t2, 0x00000300 + sw t2, 0(t1) + + /* Check switch setting */ + li t1, 0xBE000014 + lw t2, 0(t1) + and t2, t2, 0x00000100 + bne t2, zero, 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 + + /* First setup pll:s to make serial work ok */ + /* We have a 12 MHz crystal */ + li t0, SYS_CPUPLL + li t1, 0x21 /* 396 MHz */ + 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, 8 /* 96 MHz */ + sw t1, 0(t0) /* aux pll */ + sync + + /* Static memory controller */ + + /* RCE0 8MB AMD29D323 Flash */ + li t0, MEM_STCFG0 + li t1, 0x00001403 + sw t1, 0(t0) + + li t0, MEM_STTIME0 + li t1, 0xFFFFFFDD + sw t1, 0(t0) + + li t0, MEM_STADDR0 + li t1, 0x11F83FE0 + sw t1, 0(t0) + + /* RCE1 CPLD Board Logic */ + li t0, MEM_STCFG1 + li t1, 0x00000083 + sw t1, 0(t0) + + li t0, MEM_STTIME1 + li t1, 0x33030A10 + sw t1, 0(t0) + + li t0, MEM_STADDR1 + li t1, 0x11803E40 + sw t1, 0(t0) + + /* RCE2 CPLD Board Logic */ + li t0, MEM_STCFG2 + li t1, 0x00000004 + sw t1, 0(t0) + + li t0, MEM_STTIME2 + li t1, 0x08061908 + sw t1, 0(t0) + + li t0, MEM_STADDR2 + li t1, 0x12A03FC0 + sw t1, 0(t0) + + /* 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 + + /* + * Skip memory setup if we are running from memory + */ + li t0, 0x90000000 + sub t0, ra, t0 + bltz t0, skip_memsetup + nop + + /* + * SDCS0 - Not used, for SMROM + * SDCS1 - 32MB Micron 48LCBM16A2 + * SDCS2 - 32MB Micron 48LCBM16A2 + */ + li t0, MEM_SDMODE0 + li t1, 0x00000000 + sw t1, 0(t0) + + li t0, MEM_SDMODE1 + li t1, 0x00552229 + sw t1, 0(t0) + + li t0, MEM_SDMODE2 + li t1, 0x00552229 + sw t1, 0(t0) + + li t0, MEM_SDADDR0 + li t1, 0x00000000 + sw t1, 0(t0) + + li t0, MEM_SDADDR1 + li t1, 0x001003F8 + sw t1, 0(t0) + + li t0, MEM_SDADDR2 + li t1, 0x001023F8 + sw t1, 0(t0) + + sync + + li t0, MEM_SDREFCFG + li t1, 0x74000c30 /* 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, 0x76000c30 /* Enable */ + sw t1, 0(t0) + sync + + li t0, MEM_SDWRMD0 + li t1, 0x00000023 + sw t1, 0(t0) + sync + + li t0, MEM_SDWRMD1 + li t1, 0x00000023 + sw t1, 0(t0) + sync + + li t0, MEM_SDWRMD2 + li t1, 0x00000023 + sw t1, 0(t0) + sync + + /* wait 1mS after setup */ + li t1, MEM_1MS +1: add t1, -1 + bne t1, zero, 1b + nop + +skip_memsetup: + + li t0, SYS_PINFUNC + li t1, 0/*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 |