掌機 - FC3000 - Assembly - SPI(NOR Flash)

參考資料：
http://nano.lichee.pro/
https://mangopi.org/mangopi_r
https://www.allwinnertech.com/index.php?c=product&a=index&pid=4

SPI0腳位

暫存器


初始步驟：
1. 設定SPI Mode為Master
2. 設定DHB模式(避免接收多餘資料)
3. 設定CS_Level為Low
4. 設定CS_Owner為SPI Controller
5. 設定SPI CDR1為50MHz

傳送、接收步驟：
1. 清除RX、TX FIFO(FCR_REG)
2. 設定TXRX全部數量(MBC_REG)
3. 設定TX數量(MTC_REG)
4. 設定TX數量(BCC_REG)
5. 開始傳送接收(TCR_REG.XCH)
6. 等待結束後，從RXD提取資料

main.s

    .global _start

    .equ SPI0_BASE,  0x01c05000
    .equ CCU_BASE,   0x01c20000
    .equ GPIO_BASE,  0x01c20800
    .equ UART0_BASE, 0x01c25000
    
    .equ PLL_PERIPH_CTRL_REG,   0x0028
    .equ AHB_APB_HCLKC_CFG_REG, 0x0054
    .equ BUS_CLK_GATING_REG0,   0x0060
    .equ BUS_CLK_GATING_REG2,   0x0068
    .equ BUS_SOFT_RST_REG0,     0x02c0
    .equ BUS_SOFT_RST_REG2,     0x02d0
 
    .equ PC,   (0x24 * 2)
    .equ PE,   (0x24 * 4)
    .equ CFG0, 0x00
    .equ DATA, 0x10
    .equ RBR,  0x0000
    .equ DLL,  0x0000
    .equ DLH,  0x0004
    .equ IER,  0x0004
    .equ IIR,  0x0008
    .equ LCR,  0x000c
    .equ MCR,  0x0010
    .equ USR,  0x007c
 
    .equ GCR,  0x04
    .equ TCR,  0x08
    .equ IER,  0x10
    .equ ISR,  0x14
    .equ FCR,  0x18
    .equ FSR,  0x1c
    .equ WCR,  0x20
    .equ CCR,  0x24
    .equ MBC,  0x30
    .equ MTC,  0x34
    .equ BCC,  0x38
    .equ TXD,  0x200
    .equ RXD,  0x300

    .arm
    .text
_start:
    .long 0xea000016
    .byte 'e', 'G', 'O', 'N', '.', 'B', 'T', '0'
    .long 0, __spl_size
    .byte 'S', 'P', 'L', 2
    .long 0, 0
    .long 0, 0, 0, 0, 0, 0, 0, 0
    .long 0, 0, 0, 0, 0, 0, 0, 0
    
_vector:
    b reset
    b .
    b .
    b .
    b .
    b .
    b .
    b .
    
reset:
    ldr r0, =CCU_BASE
    ldr r1, =0x80041800
    str r1, [r0, #PLL_PERIPH_CTRL_REG]
    ldr r1, =0x00003180
    str r1, [r0, #AHB_APB_HCLKC_CFG_REG]
    ldr r1, =(1 << 20)
    str r1, [r0, #BUS_CLK_GATING_REG0]
    str r1, [r0, #BUS_CLK_GATING_REG2]
    str r1, [r0, #BUS_SOFT_RST_REG0]
    str r1, [r0, #BUS_SOFT_RST_REG2]
 
    ldr r0, =GPIO_BASE
    ldr r1, =0x55
    str r1, [r0, #(PE + CFG0)]
    ldr r1, =0x2222
    str r1, [r0, #(PC + CFG0)]
 
    ldr r0, =UART0_BASE
    ldr r1, =0x00
    str r1, [r0, #IER]
    ldr r1, =0xf7
    str r1, [r0, #IIR]
    ldr r1, =0x00
    str r1, [r0, #MCR]
    ldr r1, [r0, #LCR]
    orr r1, #(1 << 7)
    str r1, [r0, #LCR]
    ldr r1, =54
    str r1, [r0, #DLL]
    ldr r1, =0x00
    str r1, [r0, #DLH]
    ldr r1, [r0, #LCR]
    bic r1, #(1 << 7)
    str r1, [r0, #LCR]
    ldr r1, [r0, #LCR]
    bic r1, #0x1f
    orr r1, #0x03
    str r1, [r0, #LCR]

    ldr r4, =SPI0_BASE
    ldr r1, =(1 << 1) | (1 << 0)
    str r1, [r4, #GCR]
    ldr r1, =(1 << 2) | (1 << 8)
    str r1, [r4, #TCR]
    ldr r1, =(1 << 8)
    str r1, [r4, #CCR]
    ldr r2, =(1 << 31) | (1 << 15)
    str r2, [r4, #FCR]
1:
    ldr r1, [r4, #FCR]
    tst r1, r2
    bne 1b
    ldr r1, =4
    str r1, [r4, #MBC]
    ldr r1, =1
    str r1, [r4, #MTC]
    ldr r1, =1
    str r1, [r4, #BCC]
    ldr r1, =0x9f
    strb r1, [r4, #TXD]
    ldr r1, [r4, #TCR]
    orr r1, #(1 << 31)
    str r1, [r4, #TCR]
1:
    ldr r1, [r4, #TCR]
    tst r1, #(1 << 31)
    bne 1b

    ldrb r0, [r4, #RXD]
    bl send_byte
    ldrb r0, [r4, #RXD]
    bl send_byte
    ldrb r0, [r4, #RXD]
    bl send_byte

main:
    b main
    
send_byte:
    push {lr}
    ldr r1, =UART0_BASE
1:
    ldr r2, [r1, #USR]
    tst r2, #(1 << 1)
    beq 1b
    strb r0, [r1, #RBR]
    pop {pc}
    .end

完成