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-rw-r--r--board/pb1x00/lowlevel_init.S392
1 files changed, 392 insertions, 0 deletions
diff --git a/board/pb1x00/lowlevel_init.S b/board/pb1x00/lowlevel_init.S
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+++ b/board/pb1x00/lowlevel_init.S
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+/* 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