FreeCalypso > hg > freecalypso-tools
annotate target-utils/flash-boot-test/uartinit.S @ 816:b3724fe6c581
fc-tmsh bsim commands implemented
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Fri, 14 May 2021 17:16:43 +0000 |
parents | cc6594a7fc7a |
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rev | line source |
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cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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1 /* |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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2 * The UART initialization code in this assembly module has been lifted |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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3 * from the disassembly of the Calypso boot ROM, and slightly adapted |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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4 * for our needs. |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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5 */ |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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6 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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7 .text |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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8 .code 32 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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9 .globl uart_init |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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10 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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11 uart_init: |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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12 stmfd sp!, {r4-r11,lr} |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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13 @ prepare UART init values |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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14 mov r11, #3 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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15 mov r5, #0 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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16 mov r10, #7 @ baud rate divisor for 115200 baud |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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17 mov r9, #0x80 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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18 mov r7, #0xbf |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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19 mov r4, #7 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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20 @ UART base address |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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21 ldr r6, =uart_base |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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22 ldr r12, [r6] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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23 add r3, r12, #8 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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24 @ R3 points to register 8 (MDR1) |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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25 @ write 07 into it: reset mode |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
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26 strb r4, [r3] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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27 add r0, r12, #3 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
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28 @ R0 points to register 3 (LCR) |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
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29 @ write BF into it: map in the extended registers |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
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30 strb r7, [r0] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
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31 add r1, r12, #2 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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32 @ R1 points to register 2: EFR under current mapping |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
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33 @ set bit 4: enable enhanced functions |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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34 ldrb r8, [r1] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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35 orr r8, r8, #0x10 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
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36 strb r8, [r1] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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37 @ write 80 into LCR: map in the baud rate divisor registers |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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38 strb r9, [r0] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
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39 @ reg 2 (pointed to by R1) is now IIR/FCR |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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40 @ write 07 into FCR: FIFOs enabled and cleared, no DMA |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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41 strb r4, [r1] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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42 @ write BF into LCR again |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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43 strb r7, [r0] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
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44 @ load baud rate divisor |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
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45 strb r10, [r12] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
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46 strb r5, [r12, #1] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
parents:
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47 @ write 03 into LCR: restore normal registers, 8N1 |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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48 strb r11, [r0] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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49 @ write 00 into MDR1: plain UART mode |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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50 strb r5, [r3] |
cc6594a7fc7a
target-utils/flash-boot-test: added UART init, needed for mode 1
Mychaela Falconia <falcon@freecalypso.org>
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51 ldmfd sp!, {r4-r11,pc} |