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Diffstat (limited to 'board/eltec/elppc/asm_init.S')
| -rw-r--r-- | board/eltec/elppc/asm_init.S | 877 |
1 files changed, 877 insertions, 0 deletions
diff --git a/board/eltec/elppc/asm_init.S b/board/eltec/elppc/asm_init.S new file mode 100644 index 0000000..a5605b7 --- /dev/null +++ b/board/eltec/elppc/asm_init.S @@ -0,0 +1,877 @@ +/* + * (C) Copyright 2001 ELTEC Elektronik AG + * Frank Gottschling <fgottschling@eltec.de> + * + * ELTEC ELPPC RAM initialization + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <config.h> +#include <version.h> +#include <mpc106.h> + +#include <ppc_asm.tmpl> +#include <ppc_defs.h> + +.globl board_asm_init +board_asm_init: + +/* + * setup pointer to message block + */ + mflr r13 /* save away link register */ + bl get_lnk_reg /* r3=addr of next instruction */ + subi r4, r3, 8 /* r4=board_asm_init addr */ + addi r29, r4, (MessageBlock-board_asm_init) + +/* + * dcache_disable + */ + mfspr r3, HID0 + li r4, HID0_DCE + andc r3, r3, r4 + mr r2, r3 + ori r3, r3, HID0_DCI + sync + mtspr HID0, r3 + mtspr HID0, r2 + isync + sync +/* + * icache_disable + */ + mfspr r3, HID0 + li r4, 0 + ori r4, r4, HID0_ICE + andc r3, r3, r4 + sync + mtspr HID0, r3 +/* + * invalidate caches + */ + ori r3, r3, (HID0_ICE | HID0_ICFI | HID0_DCI | HID0_DCE) + or r4, r4, r3 + isync + mtspr HID0, r4 + andc r4, r4, r3 + isync + mtspr HID0, r4 + isync +/* + * icache_enable + */ + mfspr r3, HID0 + ori r3, r3, (HID0_ICE | HID0_ICFI) + sync + mtspr HID0, r3 + + +/* + * setup memory controller + */ + lis r1, MPC106_REG_ADDR@h + ori r1, r1, MPC106_REG_ADDR@l + lis r2, MPC106_REG_DATA@h + ori r2, r2, MPC106_REG_DATA@l + + /* Configure PICR1 */ + lis r3, MPC106_REG@h + ori r3, r3, PCI_PICR1 + stwbrx r3, 0, r1 + addis r3, r0, 0xFF14 + ori r3, r3, 0x1CC8 + eieio + stwbrx r3, 0, r2 + + /* Configure PICR2 */ + lis r3, MPC106_REG@h + ori r3, r3, PCI_PICR2 + stwbrx r3, 0, r1 + addis r3, r0, 0x0000 + ori r3, r3, 0x0000 + eieio + stwbrx r3, 0, r2 + + /* Configure EUMBAR */ + lis r3, MPC106_REG@h + ori r3, r3, 0x0078 /* offest of EUMBAR in PCI config space */ + stwbrx r3, 0, r1 + lis r3, MPC107_EUMB_ADDR@h + eieio + stwbrx r3, 0, r2 + + /* Configure Address Map B Option Reg */ + lis r3, MPC106_REG@h + ori r3, r3, 0x00e0 /* offest of AMBOR in PCI config space */ + stwbrx r3, 0, r1 + lis r3, 0 + eieio + stwbrx r3, 0, r2 + + /* Configure I2C Controller */ + lis r14, MPC107_I2C_ADDR@h /* base of I2C controller */ + ori r14, r14, MPC107_I2C_ADDR@l + lis r3, 0x2b10 /* I2C clock = 100MHz/1024 */ + stw r3, 4(r14) + li r3, 0 /* clear arbitration */ + eieio + stw r3, 12(r14) + + /* Configure MCCR1 */ + lis r3, MPC106_REG@h + ori r3, r3, MPC106_MCCR1 + stwbrx r3, 0, r1 + addis r3, r0, 0x0660 /* don't set MEMGO now ! */ + ori r3, r3, 0x0000 + eieio + stwbrx r3, 0, r2 + + /* Configure MCCR2 */ + lis r3, MPC106_REG@h + ori r3, r3, MPC106_MCCR2 + stwbrx r3, 0, r1 + addis r3, r0, 0x0400 + ori r3, r3, 0x1800 + eieio + stwbrx r3, 0, r2 + + + /* Configure MCCR3 */ + lis r3, MPC106_REG@h + ori r3, r3, MPC106_MCCR3 + stwbrx r3, 0, r1 + addis r3, r0, 0x0230 + ori r3, r3, 0x0000 + eieio + stwbrx r3, 0, r2 + + /* Configure MCCR4 */ + lis r3, MPC106_REG@h + ori r3, r3, MPC106_MCCR4 + stwbrx r3, 0, r1 + addis r3, r0, 0x2532 + ori r3, r3, 0x2220 + eieio + stwbrx r3, 0, r2 + +/* + * configure memory interface (MICRs) + */ + addis r3, r0, 0x8000 /* ADDR_80 */ + ori r3, r3, 0x0080 /* SMEMADD1 */ + stwbrx r3, 0, r1 + addis r3, r0, 0xFFFF + ori r3, r3, 0x4000 + eieio + stwbrx r3, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_84 */ + ori r3, r3, 0x0084 /* SMEMADD2 */ + stwbrx r3, 0, r1 + addis r3, r0, 0xFFFF + ori r3, r3, 0xFFFF + eieio + stwbrx r3, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_88 */ + ori r3, r3, 0x0088 /* EXTSMEM1 */ + stwbrx r3, 0, r1 + addis r3, r0, 0x0303 + ori r3, r3, 0x0000 + eieio + stwbrx r3, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_8C */ + ori r3, r3, 0x008c /* EXTSMEM2 */ + stwbrx r3, 0, r1 + addis r3, r0, 0x0303 + ori r3, r3, 0x0303 + eieio + stwbrx r3, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_90 */ + ori r3, r3, 0x0090 /* EMEMADD1 */ + stwbrx r3, 0, r1 + addis r3, r0, 0xFFFF + ori r3, r3, 0x7F3F + eieio + stwbrx r3, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_94 */ + ori r3, r3, 0x0094 /* EMEMADD2 */ + stwbrx r3, 0, r1 + addis r3, r0, 0xFFFF + ori r3, r3, 0xFFFF + eieio + stwbrx r3, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_98 */ + ori r3, r3, 0x0098 /* EXTEMEM1 */ + stwbrx r3, 0, r1 + addis r3, r0, 0x0303 + ori r3, r3, 0x0000 + eieio + stwbrx r3, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_9C */ + ori r3, r3, 0x009c /* EXTEMEM2 */ + stwbrx r3, 0, r1 + addis r3, r0, 0x0303 + ori r3, r3, 0x0303 + eieio + stwbrx r3, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_A0 */ + ori r3, r3, 0x00a0 /* MEMBNKEN */ + stwbrx r3, 0, r1 + addis r3, r0, 0x0000 + ori r3, r3, 0x0003 + eieio + stwbrx r3, 0, r2 + +/* + * must wait at least 100us after HRESET to issue a MEMGO + */ + lis r0, 1 + mtctr r0 +memStartWait: + bdnz memStartWait + +/* + * enable RAM Operations through MCCR1 (MEMGO) + */ + lis r3, 0x8000 + ori r3, r3, 0x00f0 + stwbrx r3, r0, r1 + sync + lwbrx r3, 0, r2 + lis r0, 0x0008 + or r3, r0, r3 + stwbrx r3, 0, r2 + sync + +/* + * set LEDs first time + */ + li r3, 0x1 + lis r30, CFG_USR_LED_BASE@h + stb r3, 2(r30) + sync + +/* + * init COM1 for polled output + */ + lis r8, CFG_NS16550_COM1@h /* COM1 base address*/ + ori r8, r8, CFG_NS16550_COM1@l + li r9, 0x00 + stb r9, 1(r8) /* int disabled */ + eieio + li r9, 0x00 + stb r9, 4(r8) /* modem ctrl */ + eieio + li r9, 0x80 + stb r9, 3(r8) /* link ctrl */ + eieio + li r9, (CFG_NS16550_CLK / 16 / CONFIG_BAUDRATE) + stb r9, 0(r8) /* baud rate (LSB)*/ + eieio + li r9, ((CFG_NS16550_CLK / 16 / CONFIG_BAUDRATE) >> 8) + stb r9, 1(r8) /* baud rate (MSB) */ + eieio + li r9, 0x07 + stb r9, 3(r8) /* 8 data bits, 2 stop bit, no parity */ + eieio + li r9, 0x0b + stb r9, 4(r8) /* enable the receiver and transmitter (modem ctrl) */ + eieio +waitEmpty: + lbz r9, 5(r8) /* transmit empty */ + andi. r9, r9, 0x40 + beq waitEmpty + li r9, 0x47 + stb r9, 3(r8) /* send break, 8 data bits, 2 stop bit, no parity */ + eieio + + lis r0, 0x0001 + mtctr r0 +waitCOM1: + lwz r0, 5(r8) /* load from port for delay */ + bdnz waitCOM1 + +waitEmpty1: + lbz r9, 5(r8) /* transmit empty */ + andi. r9, r9, 0x40 + beq waitEmpty1 + li r9, 0x07 + stb r9, 3(r8) /* 8 data bits, 2 stop bit, no parity */ + eieio + +/* + * intro message from message block + */ + addi r3, r29, (MnewLine-MessageBlock) + bl Printf + addi r3, r29, (MinitLogo-MessageBlock) + bl Printf + +/* + * memory cofiguration using SPD information stored on the SODIMMs + */ + addi r3, r29, (Mspd01-MessageBlock) + bl Printf + + li r17, 0 + + li r3, 0x0002 /* get RAM type from spd for bank0/1 */ + bl spdRead + + cmpi 0, 0, r3, -1 /* error ? */ + bne noSpdError + + addi r3, r29, (Mfail-MessageBlock) + bl Printf + + li r6, 0xe /* error codes in r6 and r7 */ + li r7, 0x0 + b toggleError /* fail - loop forever */ + +noSpdError: + mr r15, r3 /* save r3 */ + + addi r3, r29, (Mok-MessageBlock) + bl Printf + + cmpli 0, 0, r15, 0x0004 /* SDRAM ? */ + beq isSDRAM + + addi r3, r29, (MramTyp-MessageBlock) + bl Printf + + li r6, 0xd /* error codes in r6 and r7 */ + li r7, 0x0 + b toggleError /* fail - loop forever */ + +isSDRAM: + li r3, 0x0012 /* get supported CAS latencies from byte 18 */ + bl spdRead + mr r15, r3 + li r3, 0x09 + andi. r0, r15, 0x04 + bne maxCLis3 + li r3, 0x17 +maxCLis3: + andi. r0, r15, 0x02 + bne CL2 + + addi r3, r29, (MramTyp-MessageBlock) + bl Printf + + li r6, 0xc /* error codes in r6 and r7 */ + li r7, 0x0 + b toggleError /* fail - loop forever */ +CL2: + bl spdRead + cmpli 0, 0, r3, 0xa1 /* cycle time must be 10ns max. */ + blt speedOk + + addi r3, r29, (MramTyp-MessageBlock) + bl Printf + + li r6, 0xb /* error codes in r6 and r7 */ + li r7, 0x0 + b toggleError /* fail - loop forever */ +speedOk: + lis r20, 0x06e8 /* preset MCR1 value */ + + li r3, 0x0011 /* get number of internal banks from spd for bank0/1 */ + bl spdRead + + cmpli 0, 0, r3, 0x02 + beq SD_2B + cmpli 0, 0, r3, 0x04 + beq SD_4B +memConfErr: + addi r3, r29, (MramConfErr-MessageBlock) + bl Printf + + li r6, 0xa /* error codes in r6 and r7 */ + li r7, 0x0 + b toggleError /* fail - loop forever */ + +SD_2B: + li r3, 0x0003 /* get number of row bits from spd for bank0/1 */ + bl spdRead + cmpli 0, 0, r3, 0x0b + beq row11x2 + cmpli 0, 0, r3, 0x0c + beq row12x2or13x2 + cmpli 0, 0, r3, 0x0d + beq row12x2or13x2 + b memConfErr +SD_4B: + li r3, 0x0003 /* get number of row bits from spd for bank0/1 */ + bl spdRead + cmpli 0, 0, r3, 0x0b + beq row11x4or12x4 + cmpli 0, 0, r3, 0x0c + beq row11x4or12x4 + cmpli 0, 0, r3, 0x0d + beq row13x4 + b memConfErr +row12x2or13x2: + ori r20, r20, 0x05 + b row11x4or12x4 +row13x4: + ori r20, r20, 0x0a + b row11x4or12x4 +row11x2: + ori r20, r20, 0x0f +row11x4or12x4: + /* get the size of bank 0-1 */ + + li r3, 0x001f /* get bank size from spd for bank0/1 */ + bl spdRead + + rlwinm r16, r3, 2, 24, 29 /* calculate size in MByte (128 MB max.) */ + + li r3, 0x0005 /* get number of banks from spd for bank0/1 */ + bl spdRead + + cmpi 0, 0, r3, 2 /* 2 banks ? */ + bne SDRAMnobank1 + + mr r17, r16 + +SDRAMnobank1: + li r3, 0x000c /* get refresh from spd for bank0/1 */ + bl spdRead + andi. r3, r3, 0x007f /* mask selfrefresh bit */ + li r4, 0x1800 /* refesh cycle 1536 clocks left shifted 2 */ + cmpli 0, 0, r3, 0x0000 /* 15.6 us ? */ + beq writeRefresh + + li r4, 0x0c00 /* refesh cycle 768 clocks left shifted 2 */ + cmpli 0, 0, r3, 0x0002 /* 7.8 us ? */ + beq writeRefresh + + li r4, 0x3000 /* refesh cycle 3072 clocks left shifted 2 */ + cmpli 0, 0, r3, 0x0003 /* 31.3 us ? */ + beq writeRefresh + + li r4, 0x6000 /* refesh cycle 6144 clocks left shifted 2 */ + cmpli 0, 0, r3, 0x0004 /* 62.5 us ? */ + beq writeRefresh + + li r4, 0 + ori r4, r4, 0xc000 /* refesh cycle 8224 clocks left shifted 2 */ + cmpli 0, 0, r3, 0x0005 /* 125 us ? */ + beq writeRefresh + + b memConfErr + +writeRefresh: + lis r21, 0x0400 /* preset MCCR2 value */ + or r21, r21, r4 + + /* Overwrite MCCR1 */ + lis r3, MPC106_REG@h + ori r3, r3, MPC106_MCCR1 + stwbrx r3, 0, r1 + eieio + stwbrx r20, 0, r2 + + /* Overwrite MCCR2 */ + lis r3, MPC106_REG@h + ori r3, r3, MPC106_MCCR2 + stwbrx r3, 0, r1 + eieio + stwbrx r21, 0, r2 + + /* set the memory boundary registers for bank 0-3 */ + li r20, 0 + lis r23, 0x0303 + lis r24, 0x0303 + subi r21, r16, 1 /* calculate end address bank0 */ + li r22, 1 + + cmpi 0, 0, r17, 0 /* bank1 present ? */ + beq nobank1 + + andi. r3, r16, 0x00ff /* calculate start address of bank1 */ + andi. r4, r16, 0x0300 + rlwinm r3, r3, 8, 16, 23 + or r20, r20, r3 + or r23, r23, r4 + + add r16, r16, r17 /* add to total memory size */ + + subi r3, r16, 1 /* calculate end address of bank1 */ + andi. r4, r3, 0x0300 + andi. r3, r3, 0x00ff + rlwinm r3, r3, 8, 16, 23 + or r21, r21, r3 + or r24, r24, r4 + + ori r22, r22, 2 /* enable bank1 */ + b bankOk +nobank1: + ori r23, r23, 0x0300 /* set bank1 start to unused area */ + ori r24, r24, 0x0300 /* set bank1 end to unused area */ +bankOk: + addi r3, r29, (Mactivate-MessageBlock) + bl Printf + mr r3, r16 + bl OutDec + addi r3, r29, (Mact0123e-MessageBlock) + bl Printf + +/* + * overwrite MSAR1, MEAR1, EMSAR1, and EMEAR1 + */ + addis r3, r0, 0x8000 /* ADDR_80 */ + ori r3, r3, 0x0080 /* MSAR1 */ + stwbrx r3, 0, r1 + eieio + stwbrx r20, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_88 */ + ori r3, r3, 0x0088 /* EMSAR1 */ + stwbrx r3, 0, r1 + eieio + stwbrx r23, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_90 */ + ori r3, r3, 0x0090 /* MEAR1 */ + stwbrx r3, 0, r1 + eieio + stwbrx r21, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_98 */ + ori r3, r3, 0x0098 /* EMEAR1 */ + stwbrx r3, 0, r1 + eieio + stwbrx r24, 0, r2 + + addis r3, r0, 0x8000 /* ADDR_A0 */ + ori r3, r3, 0x00a0 /* MBER */ + stwbrx r3, 0, r1 + eieio + stwbrx r22, 0, r2 + +/* + * delay to let SDRAM go through several initialization/refresh cycles + */ + lis r3, 3 + mtctr r3 +memStartWait_1: + bdnz memStartWait_1 + eieio + +/* + * set LEDs end + */ + li r3, 0xf + lis r30, CFG_USR_LED_BASE@h + stb r3, 2(r30) + sync + + mtlr r13 + blr /* EXIT board_asm_init ... */ + +/*----------------------------------------------------------------------------*/ +/* + * print a message to COM1 in polling mode (r10=COM1 port, r3=(char*)string) + */ + +Printf: + lis r10, CFG_NS16550_COM1@h /* COM1 base address*/ + ori r10, r10, CFG_NS16550_COM1@l +WaitChr: + lbz r0, 5(r10) /* read link status */ + eieio + andi. r0, r0, 0x40 /* mask transmitter empty bit */ + beq cr0, WaitChr /* wait till empty */ + lbzx r0, r0, r3 /* get char */ + stb r0, 0(r10) /* write to transmit reg */ + eieio + addi r3, r3, 1 /* next char */ + lbzx r0, r0, r3 /* get char */ + cmpwi cr1, r0, 0 /* end of string ? */ + bne cr1, WaitChr + blr + +/* + * print a char to COM1 in polling mode (r10=COM1 port, r3=char) + */ +OutChr: + lis r10, CFG_NS16550_COM1@h /* COM1 base address*/ + ori r10, r10, CFG_NS16550_COM1@l +OutChr1: + lbz r0, 5(r10) /* read link status */ + eieio + andi. r0, r0, 0x40 /* mask transmitter empty bit */ + beq cr0, OutChr1 /* wait till empty */ + stb r3, 0(r10) /* write to transmit reg */ + eieio + blr + +/* + * print 8/4/2 digits hex value to COM1 in polling mode (r10=COM1 port, r3=val) + */ +OutHex2: + li r9, 4 /* shift reg for 2 digits */ + b OHstart +OutHex4: + li r9, 12 /* shift reg for 4 digits */ + b OHstart +OutHex: + li r9, 28 /* shift reg for 8 digits */ +OHstart: + lis r10, CFG_NS16550_COM1@h /* COM1 base address*/ + ori r10, r10, CFG_NS16550_COM1@l +OutDig: + lbz r0, 0(r29) /* slow down dummy read */ + lbz r0, 5(r10) /* read link status */ + eieio + andi. r0, r0, 0x40 /* mask transmitter empty bit */ + beq cr0, OutDig + sraw r0, r3, r9 + clrlwi r0, r0, 28 + cmpwi cr1, r0, 9 + ble cr1, digIsNum + addic r0, r0, 55 + b nextDig +digIsNum: + addic r0, r0, 48 +nextDig: + stb r0, 0(r10) /* write to transmit reg */ + eieio + addic. r9, r9, -4 + bge OutDig + blr + +/* + * print 3 digits hdec value to COM1 in polling mode + * (r10=COM1 port, r3=val, r7=x00, r8=x0, r9=x, r0, r6=scratch) + */ +OutDec: + li r6, 10 + divwu r0, r3, r6 /* r0 = r3 / 10, r9 = r3 mod 10 */ + mullw r10, r0, r6 + subf r9, r10, r3 + mr r3, r0 + divwu r0, r3, r6 /* r0 = r3 / 10, r8 = r3 mod 10 */ + mullw r10, r0, r6 + subf r8, r10, r3 + mr r3, r0 + divwu r0, r3, r6 /* r0 = r3 / 10, r7 = r3 mod 10 */ + mullw r10, r0, r6 + subf r7, r10, r3 + lis r10, CFG_NS16550_COM1@h /* COM1 base address*/ + ori r10, r10, CFG_NS16550_COM1@l + or. r7, r7, r7 + bne noblank1 + li r3, 0x20 + b OutDec4 +noblank1: + addi r3, r7, 48 /* convert to ASCII */ +OutDec4: + lbz r0, 0(r29) /* slow down dummy read */ + lbz r0, 5(r10) /* read link status */ + eieio + andi. r0, r0, 0x40 /* mask transmitter empty bit */ + beq cr0, OutDec4 + stb r3, 0(r10) /* x00 to transmit */ + eieio + or. r7, r7, r8 + beq OutDec5 + addi r3, r8, 48 /* convert to ASCII */ +OutDec5: + lbz r0, 0(r29) /* slow down dummy read */ + lbz r0, 5(r10) /* read link status */ + eieio + andi. r0, r0, 0x40 /* mask transmitter empty bit */ + beq cr0, OutDec5 + stb r3, 0(r10) /* x0 to transmit */ + eieio + addi r3, r9, 48 /* convert to ASCII */ +OutDec6: + lbz r0, 0(r29) /* slow down dummy read */ + lbz r0, 5(r10) /* read link status */ + eieio + andi. r0, r0, 0x40 /* mask transmitter empty bit */ + beq cr0, OutDec6 + stb r3, 0(r10) /* x to transmit */ + eieio + blr + +/* + * hang endless loop + */ +toggleError: /* fail type in r6, r7=0xff, toggle LEDs */ + stb r7, 2(r30) /* r7 to LED */ + li r0, 0 + lis r9, 127 + ori r9, r9, 65535 +toggleError1: + addic r0, r0, 1 + cmpw cr1, r0, r9 + ble cr1, toggleError1 + stb r6, 2(r30) /* r6 to LED */ + li r0, 0 + lis r9, 127 + ori r9, r9, 65535 +toggleError2: + addic r0, r0, 1 + cmpw cr1, r0, r9 + ble cr1, toggleError2 + b toggleError + +/* + * routines to read from ram spd + */ +spdWaitIdle: + lis r0, 0x1 /* timeout for about 100us */ + mtctr r0 +iSpd: + lbz r10, 12(r14) + andi. r10, r10, 0x20 /* mask and test MBB */ + beq idle + bdnz iSpd + orc. r10, r0, r0 /* return -1 to caller */ +idle: + bclr 20, 0 /* return to caller */ + +waitSpd: + lis r0, 0x10 /* timeout for about 1.5ms */ + mtctr r0 +wSpd: + lbz r10, 12(r14) + andi. r10, r10, 0x82 + cmpli 0, 0, r10, 0x82 /* test MCF and MIF set */ + beq wend + bdnz wSpd + orc. r10, r0, r0 /* return -1 to caller */ + bclr 20, 0 /* return to caller */ + +wend: + li r10, 0 + stb r10, 12(r14) /* clear status */ + bclr 20, 0 /* return to caller */ + +/* + * spdread + * in: r3 adr to read + * out: r3 val or -1 for error + * uses r10, assumes that r14 points to I2C controller + */ +spdRead: + mfspr r25, 8 /* save link register */ + + bl spdWaitIdle + bne spdErr + + li r10, 0x80 /* start with MEN */ + stb r10, 8(r14) + eieio + + li r10, 0xb0 /* start as master */ + stb r10, 8(r14) + eieio + + li r10, 0xa0 /* write device 0xA0 */ + stb r10, 16(r14) + eieio + bl waitSpd + bne spdErr + + lbz r10, 12(r14) /* test ACK */ + andi. r10, r10, 0x01 + bne gotNoAck + + stb r3, 16(r14) /* data address */ + eieio + bl waitSpd + bne spdErr + + + li r10, 0xb4 /* switch to read - restart */ + stb r10, 8(r14) + eieio + + li r10, 0xa1 /* read device 0xA0 */ + stb r10, 16(r14) + eieio + bl waitSpd + bne spdErr + + li r10, 0xa8 /* no ACK */ + stb r10, 8(r14) + eieio + + lbz r10, 16(r14) /* trigger read next byte */ + eieio + bl waitSpd + bne spdErr + + li r10, 0x88 /* generate STOP condition */ + stb r10, 8(r14) + eieio + + lbz r3, 16(r14) /* return read byte */ + + mtspr 8, r25 /* restore link register */ + blr + +gotNoAck: + li r10, 0x80 /* generate STOP condition */ + stb r10, 8(r14) + eieio +spdErr: + orc r3, r0, r0 /* return -1 */ + mtspr 8, r25 /* restore link register */ + blr + +get_lnk_reg: + mflr r3 /* return link reg */ + blr + +MessageBlock: + +MinitLogo: + .ascii "\015\012*** ELTEC Elektronik, Mainz ***\015\012" + .ascii "\015\012Initialising RAM\015\012\000" +Mspd01: + .ascii " Reading SPD of SODIMM ...... \000" +MramTyp: + .ascii "\015\012\SDRAM with CL=2 at 100 MHz required!\015\012\000" +MramConfErr: + .ascii "\015\012\Unsupported SODIMM Configuration!\015\012\000" +Mactivate: + .ascii " Activating \000" +Mact0123e: + .ascii " MByte.\015\012\000" +Mok: + .ascii "OK \015\012\000" +Mfail: + .ascii "FAILED \015\012\000" +MnewLine: + .ascii "\015\012\000" + .align 4 |