FreeCalypso > hg > freecalypso-tools

annotate target-utils/flash-boot-test/uartinit.S @ 921:74d284add54d

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fc-fsio: guard against bogus readdir results from the target If the FFS being operated on contains SE K2x0 extended filenames, readdir will return strings that are bad for printing. We need to guard against this possibility, and also against possible other bogosity that could be sent by other alien firmwares.
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 31 Dec 2022 22:55:23 +0000
parents cc6594a7fc7a
children
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cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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1 /*
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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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
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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
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4 * for our needs.
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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5 */
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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6
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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7 .text
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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8 .code 32
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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9 .globl uart_init
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10
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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11 uart_init:
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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12 stmfd sp!, {r4-r11,lr}
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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13 @ prepare UART init values
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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14 mov r11, #3
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15 mov r5, #0
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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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
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17 mov r9, #0x80
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18 mov r7, #0xbf
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19 mov r4, #7
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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20 @ UART base address
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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21 ldr r6, =uart_base
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22 ldr r12, [r6]
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23 add r3, r12, #8
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24 @ R3 points to register 8 (MDR1)
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25 @ write 07 into it: reset mode
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26 strb r4, [r3]
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27 add r0, r12, #3
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28 @ R0 points to register 3 (LCR)
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29 @ write BF into it: map in the extended registers
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30 strb r7, [r0]
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31 add r1, r12, #2
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32 @ R1 points to register 2: EFR under current mapping
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33 @ set bit 4: enable enhanced functions
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34 ldrb r8, [r1]
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35 orr r8, r8, #0x10
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36 strb r8, [r1]
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37 @ write 80 into LCR: map in the baud rate divisor registers
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38 strb r9, [r0]
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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
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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
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41 strb r4, [r1]
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42 @ write BF into LCR again
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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43 strb r7, [r0]
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44 @ load baud rate divisor
cc6594a7fc7a target-utils/flash-boot-test: added UART init, needed for mode 1
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45 strb r10, [r12]
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46 strb r5, [r12, #1]
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47 @ write 03 into LCR: restore normal registers, 8N1
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48 strb r11, [r0]
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49 @ write 00 into MDR1: plain UART mode
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50 strb r5, [r3]
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51 ldmfd sp!, {r4-r11,pc}