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-rw-r--r--board/gth2/lowlevel_init.S454
1 files changed, 454 insertions, 0 deletions
diff --git a/board/gth2/lowlevel_init.S b/board/gth2/lowlevel_init.S
new file mode 100644
index 0000000..983ff70
--- /dev/null
+++ b/board/gth2/lowlevel_init.S
@@ -0,0 +1,454 @@
+/* Memory sub-system initialization code */
+
+#include <config.h>
+#include <version.h>
+#include <asm/regdef.h>
+#include <asm/au1x00.h>
+#include <asm/mipsregs.h>
+
+#define CP0_Config0 $16
+#define MEM_1MS ((CFG_MHZ) * 1000)
+#define GPIO_RJ1LY (1<<22)
+#define GPIO_CFRESET (1<<10)
+
+ .text
+ .set noreorder
+ .set mips32
+
+ .globl lowlevel_init
+lowlevel_init:
+ /*
+ * 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
+
+ /* 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 12.5 MHz crystal */
+ li t0, SYS_CPUPLL
+ li t1, 0x28 /* CPU clock, 500 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, 0
+ 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:
+
+ /* Static memory controller */
+
+ /* RCE0 AMD 29LV800 Flash */
+ li t0, MEM_STCFG0
+ li t1, 0x00000243
+ sw t1, 0(t0)
+
+ li t0, MEM_STTIME0
+ li t1, 0x040181D7 /* FIXME */
+ sw t1, 0(t0)
+
+ li t0, MEM_STADDR0
+ li t1, 0x11E03F80
+ sw t1, 0(t0)
+
+ /* RCE1 PCMCIA 250ns */
+ li t0, MEM_STCFG1
+ li t1, 0x00000002
+ sw t1, 0(t0)
+
+ li t0, MEM_STTIME1
+ li t1, 0x280E3E07
+ sw t1, 0(t0)
+
+ li t0, MEM_STADDR1
+ li t1, 0x10000000
+ sw t1, 0(t0)
+
+ /* RCE2 CP Altera */
+ li t0, MEM_STCFG2
+ li t1, 0x00000280 /* BE, EW */
+ sw t1, 0(t0)
+
+ li t0, MEM_STTIME2
+ li t1, 0x0303000c
+ sw t1, 0(t0)
+
+ li t0, MEM_STADDR2
+ li t1, 0x10c03f80 /* 1 MB */
+ sw t1, 0(t0)
+
+ /* RCE3 DP Altera */
+ li t0, MEM_STCFG3
+ li t1, 0x00000280 /* BE, EW */
+ sw t1, 0(t0)
+
+ li t0, MEM_STTIME3
+ li t1, 0x0303000c
+ sw t1, 0(t0)
+
+ li t0, MEM_STADDR3
+ li t1, 0x10e03f80 /* 1 MB */
+ 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
+
+
+/* SDCS 0 SDRAM */
+ li t0, MEM_SDMODE0
+ li t1, 0x592CD1
+ sw t1, 0(t0)
+
+ li t0, MEM_SDMODE1
+ li t1, 0x00000000
+ sw t1, 0(t0)
+
+ li t0, MEM_SDMODE2
+ li t1, 0x00000000
+ sw t1, 0(t0)
+
+/* 64 MB SDRAM at addr 0 */
+ li t0, MEM_SDADDR0
+ li t1, 0x001003F0
+ sw t1, 0(t0)
+
+
+ li t0, MEM_SDADDR1
+ li t1, 0x00000000
+ sw t1, 0(t0)
+
+ li t0, MEM_SDADDR2
+ li t1, 0x00000000
+ sw t1, 0(t0)
+
+ sync
+
+ li t0, MEM_SDREFCFG
+ li t1, 0x880007A1 /* 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, 0x8A0007A1 /* Enable */
+ sw t1, 0(t0)
+ sync
+
+ li t0, MEM_SDWRMD0
+ 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
+
+ /* Setup GPIO pins */
+
+ li t0, SYS_PINFUNC
+ li t1, 0x00007025 /* 0x8080 */
+ sw t1, 0(t0)
+
+ li t0, SYS_TRIOUTCLR
+ li t1, 0xFFFFFFFF /* 0x1FFF */
+ sw t1, 0(t0)
+
+ /* Turn yellow front led on */
+ /* Release reset on CF */
+ li t0, SYS_OUTPUTCLR
+ li t1, GPIO_RJ1LG
+ sw t1, 0(t0)
+ li t0, SYS_OUTPUTSET
+ li t1, GPIO_RJ1LY|GPIO_CFRESET
+ sw t1, 0(t0)
+ sync
+ j clearmem
+ nop
+
+ .globl memtest
+memtest:
+ /* Fill memory with address */
+ li t0, 0x80000000
+ li t1, 0xFFF000 /* 64 MB */
+mt0: sw t0, 0(t0)
+ add t1, -1
+ add t0, 4
+ bne t1, zero, mt0
+ nop
+ nop
+ /* Verify addr */
+ li t0, 0x80000000
+ li t1, 0xFFF000 /* 64 MB */
+mt1: lw t2, 0(t0)
+ bne t0, t2, memhang
+ add t1, -1
+ add t0, 4
+ bne t1, zero, mt1
+ nop
+ nop
+ .globl clearmem
+clearmem:
+ /* Clear memory */
+ li t0, 0x80000000
+ li t1, 0xFFF000 /* 64 MB */
+mtc: sw zero, 0(t0)
+ add t1, -1
+ add t0, 4
+ bne t1, zero, mtc
+ nop
+ nop
+memtestend:
+ j ra
+ nop
+
+memhang:
+ b memhang
+ nop
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