| /* |
| * Copyright (C) 2016 Marvell International Ltd. |
| * |
| * SPDX-License-Identifier: BSD-3-Clause |
| * https://spdx.org/licenses |
| */ |
| |
| #include <arch.h> |
| #include <asm_macros.S> |
| #include <console_macros.S> |
| #include <drivers/marvell/uart/a3700_console.h> |
| |
| /* |
| * "core" functions are low-level implementations that don't require |
| * writable memory and are thus safe to call in BL1 crash context. |
| */ |
| .globl console_a3700_core_putc |
| .globl console_a3700_core_init |
| .globl console_a3700_core_getc |
| .globl console_a3700_core_flush |
| |
| .globl console_a3700_putc |
| .globl console_a3700_getc |
| .globl console_a3700_flush |
| |
| /* ----------------------------------------------- |
| * int console_a3700_core_init(unsigned long base_addr, |
| * unsigned int uart_clk, unsigned int baud_rate) |
| * Function to initialize the console without a |
| * C Runtime to print debug information. This |
| * function will be accessed by console_init and |
| * crash reporting. |
| * In: x0 - console base address |
| * w1 - Uart clock in Hz |
| * w2 - Baud rate |
| * Out: return 1 on success |
| * Clobber list : x1, x2, x3, x4 |
| * ----------------------------------------------- |
| */ |
| func console_a3700_core_init |
| /* Check the input base address */ |
| cbz x0, init_fail |
| /* Check baud rate and uart clock for sanity */ |
| cbz w1, init_fail |
| cbz w2, init_fail |
| |
| /* |
| * Wait for the TX (THR and TSR) to be empty. If wait for 3ms, the TX FIFO is |
| * still not empty, TX FIFO will reset by all means. |
| */ |
| mov w4, #30 /* max time out 30 * 100 us */ |
| 2: |
| /* Check whether TX (THR and TSR) is empty */ |
| ldr w3, [x0, #UART_STATUS_REG] |
| and w3, w3, #UARTLSR_TXEMPTY |
| cmp w3, #0 |
| b.ne 4f |
| |
| /* Delay */ |
| mov w3, #60000 /* 60000 cycles of below 3 instructions on 1200 MHz CPU ~~ 100 us */ |
| 3: |
| sub w3, w3, #1 |
| cmp w3, #0 |
| b.ne 3b |
| |
| /* Check whether wait timeout expired */ |
| sub w4, w4, #1 |
| cmp w4, #0 |
| b.ne 2b |
| |
| 4: |
| /* Reset FIFO */ |
| mov w3, #UART_CTRL_RXFIFO_RESET |
| orr w3, w3, #UART_CTRL_TXFIFO_RESET |
| str w3, [x0, #UART_CTRL_REG] |
| |
| /* Delay */ |
| mov w3, #2000 |
| 1: |
| sub w3, w3, #1 |
| cmp w3, #0 |
| b.ne 1b |
| |
| /* Program the baudrate */ |
| /* Divisor = Round(Uartclock / (16 * baudrate)) */ |
| lsl w2, w2, #4 |
| add w1, w1, w2, lsr #1 |
| udiv w2, w1, w2 |
| and w2, w2, #0x3ff /* clear all other bits to use default clock */ |
| |
| str w2, [x0, #UART_BAUD_REG]/* set baud rate divisor */ |
| |
| /* Set UART to default 16X scheme */ |
| mov w3, #0 |
| str w3, [x0, #UART_POSSR_REG] |
| |
| /* No Parity, 1 Stop */ |
| mov w3, #0 |
| str w3, [x0, #UART_CTRL_REG] |
| |
| mov w0, #1 |
| ret |
| init_fail: |
| mov w0, #0 |
| ret |
| endfunc console_a3700_core_init |
| |
| .globl console_a3700_register |
| |
| /* ----------------------------------------------- |
| * int console_a3700_register(console_t *console, |
| uintptr_t base, uint32_t clk, uint32_t baud) |
| * Function to initialize and register a new a3700 |
| * console. Storage passed in for the console struct |
| * *must* be persistent (i.e. not from the stack). |
| * In: x0 - UART register base address |
| * w1 - UART clock in Hz |
| * w2 - Baud rate |
| * x3 - pointer to empty console_t struct |
| * Out: return 1 on success, 0 on error |
| * Clobber list : x0, x1, x2, x3, x4, x6, x7, x14 |
| * ----------------------------------------------- |
| */ |
| func console_a3700_register |
| mov x7, x30 |
| mov x6, x3 |
| cbz x6, register_fail |
| str x0, [x6, #CONSOLE_T_BASE] |
| |
| bl console_a3700_core_init |
| cbz x0, register_fail |
| |
| mov x0, x6 |
| mov x30, x7 |
| finish_console_register a3700, putc=1, getc=1, flush=1 |
| |
| register_fail: |
| ret x7 |
| endfunc console_a3700_register |
| |
| /* -------------------------------------------------------- |
| * int console_a3700_core_putc(int c, unsigned int base_addr) |
| * Function to output a character over the console. It |
| * returns the character printed on success or -1 on error. |
| * In : w0 - character to be printed |
| * x1 - console base address |
| * Out : return -1 on error else return character. |
| * Clobber list : x2 |
| * -------------------------------------------------------- |
| */ |
| func console_a3700_core_putc |
| /* Check the input parameter */ |
| cbz x1, putc_error |
| |
| /* Prepend '\r' to '\n' */ |
| cmp w0, #0xA |
| b.ne 2f |
| /* Check if the transmit FIFO is full */ |
| 1: ldr w2, [x1, #UART_STATUS_REG] |
| and w2, w2, #UARTLSR_TXFIFOFULL |
| cmp w2, #UARTLSR_TXFIFOFULL |
| b.eq 1b |
| mov w2, #0xD /* '\r' */ |
| str w2, [x1, #UART_TX_REG] |
| |
| /* Check if the transmit FIFO is full */ |
| 2: ldr w2, [x1, #UART_STATUS_REG] |
| and w2, w2, #UARTLSR_TXFIFOFULL |
| cmp w2, #UARTLSR_TXFIFOFULL |
| b.eq 2b |
| str w0, [x1, #UART_TX_REG] |
| ret |
| putc_error: |
| mov w0, #-1 |
| ret |
| endfunc console_a3700_core_putc |
| |
| /* -------------------------------------------------------- |
| * int console_a3700_putc(int c, console_t *console) |
| * Function to output a character over the console. It |
| * returns the character printed on success or -1 on error. |
| * In : w0 - character to be printed |
| * x1 - pointer to console_t structure |
| * Out : return -1 on error else return character. |
| * Clobber list : x2 |
| * -------------------------------------------------------- |
| */ |
| func console_a3700_putc |
| ldr x1, [x1, #CONSOLE_T_BASE] |
| b console_a3700_core_putc |
| endfunc console_a3700_putc |
| |
| /* --------------------------------------------- |
| * int console_a3700_core_getc(void) |
| * Function to get a character from the console. |
| * It returns the character grabbed on success |
| * or -1 if no character is available. |
| * In : w0 - console base address |
| * Out : w0 - character if available, else -1 |
| * Clobber list : x0, x1 |
| * --------------------------------------------- |
| */ |
| func console_a3700_core_getc |
| /* Check if there is a pending character */ |
| ldr w1, [x0, #UART_STATUS_REG] |
| and w1, w1, #UARTLSR_RXRDY |
| cmp w1, #UARTLSR_RXRDY |
| b.ne getc_no_char |
| ldr w0, [x0, #UART_RX_REG] |
| and w0, w0, #0xff |
| ret |
| getc_no_char: |
| mov w0, #ERROR_NO_PENDING_CHAR |
| ret |
| endfunc console_a3700_core_getc |
| |
| /* --------------------------------------------- |
| * int console_a3700_getc(console_t *console) |
| * Function to get a character from the console. |
| * It returns the character grabbed on success |
| * or -1 on if no character is available. |
| * In : x0 - pointer to console_t structure |
| * Out : w0 - character if available, else -1 |
| * Clobber list : x0, x1 |
| * --------------------------------------------- |
| */ |
| func console_a3700_getc |
| ldr x0, [x0, #CONSOLE_T_BASE] |
| b console_a3700_core_getc |
| endfunc console_a3700_getc |
| |
| /* --------------------------------------------- |
| * void console_a3700_core_flush(uintptr_t base_addr) |
| * Function to force a write of all buffered |
| * data that hasn't been output. |
| * In : x0 - console base address |
| * Out : void. |
| * Clobber list : x0, x1 |
| * --------------------------------------------- |
| */ |
| func console_a3700_core_flush |
| /* Wait for the TX (THR and TSR) to be empty */ |
| 1: ldr w1, [x0, #UART_STATUS_REG] |
| and w1, w1, #UARTLSR_TXEMPTY |
| cmp w1, #UARTLSR_TXEMPTY |
| b.ne 1b |
| ret |
| endfunc console_a3700_core_flush |
| |
| /* --------------------------------------------- |
| * void console_a3700_flush(console_t *console) |
| * Function to force a write of all buffered |
| * data that hasn't been output. |
| * In : x0 - pointer to console_t structure |
| * Out : void. |
| * Clobber list : x0, x1 |
| * --------------------------------------------- |
| */ |
| func console_a3700_flush |
| ldr x0, [x0, #CONSOLE_T_BASE] |
| b console_a3700_core_flush |
| endfunc console_a3700_flush |
| |