/* * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of ARM nor the names of its contributors may be used * to endorse or promote products derived from this software without specific * prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include #include #include "nxp_console.h" .globl console_init .globl console_putc .globl console_getc .globl console_flush .globl console_core_init .globl console_core_putc .globl console_core_getc .globl console_core_flush /* * The console base is in the data section and not in .bss * even though it is zero-init. In particular, this allows * the console functions to start using this variable before * the runtime memory is initialized for images which do not * need to copy the .data section from ROM to RAM. */ .section .data.console_base ; .align 2 console_base: .word 0x0 /* ----------------------------------------------- * int console_init(uintptr_t base_addr, * unsigned int uart_clk, unsigned int baud_rate) * Function to initialize the console without a * C Runtime to print debug information. It saves * the console base to the data section. * In: r0 - console base address * r1 - Uart clock in Hz * r2 - Baud rate * out: return 1 on success else 0 on error * Clobber list : r1 - r3 * ----------------------------------------------- */ func console_init ldr r3, =console_base str r0, [r3] b console_core_init endfunc console_init /* ----------------------------------------------- * int console_core_init(uintptr_t 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: r0 - console base address * r1 - Uart clock in Hz * r2 - Baud rate * Out: return 1 on success else 0 on error * Clobber list : r1, r2, r3, r4 * ----------------------------------------------- */ func console_core_init push {r4} /* Check the input base address */ cmp r0, #0 beq core_init_fail /* Check baud rate and uart clock for sanity */ cmp r1, #0 beq core_init_fail cmp r2, #0 beq core_init_fail /* Free up r1 as a scratch reg */ mov r4, r0 mov r0, r1 /* Reset UART via CR2 */ add r1, r4, #MXC_UART_CR2_OFFSET movs r3, #0 str r3, [r4, #MXC_UART_CR2_OFFSET] /* Wait for reset complete */ __wait_cr2_reset: ldr r3, [r1, #0] ands r3, #MXC_UART_CR2_SRST beq __wait_cr2_reset /* Enable UART */ movs r3, #MXC_UART_CR1_UARTEN mov r1, r2 str r3, [r4, #MXC_UART_CR1_OFFSET] /* * Ignore RTC/CTS - disable reset * Magic value #16423 => * MXC_UART_CR2_IRTS | MXC_UART_CR2_WS | MXC_UART_CR2_TXEN | MXC_UART_CR2_RXEN | MXC_UART_CR2_SRST */ movw r3, #16423 str r3, [r4, #MXC_UART_CR2_OFFSET] /* * No parity, autobaud detect-old, rxdmuxsel=1 (fixed i.mx7) * Magic value => #132 * MXC_UART_CR3_ADNIMP | MXC_UART_CR3_RXDMUXSEL */ movs r3, #132 str r3, [r4, #MXC_UART_CR3_OFFSET] /* * Set CTS FIFO trigger to 32 bytes bits 15:10 * Magic value => #32768 * FIFO trigger bitmask 100000 * */ mov r3, #32768 str r3, [r4, #MXC_UART_CR4_OFFSET] /* * TX/RX-thresh = 2 bytes, DCE (bit6 = 0), refclk @24MHz / 4 * Magic value #2562 * MXC_UART_FCR_TXTL(TX_RX_THRESH) | MXC_UART_FCR_RXTL(TX_RX_THRESH) | MXC_UART_FCR_RFDIV2 */ movw r3, #2562 str r3, [r4, #MXC_UART_FCR_OFFSET] /* This BIR should be set to 0x0F prior to writing the BMR */ movs r3, #15 str r3, [r4, #MXC_UART_BIR_OFFSET] /* Hard-code to 115200 @ 24 MHz */ movs r0, #104 str r0, [r4, #MXC_UART_BMR_OFFSET] /* Indicate success */ movs r0, #1 pop {r4} bx lr core_init_fail: pop {r4} mov r0, #0 bx lr endfunc console_core_init /* --------------------------------------------- * int console_putc(int c) * Function to output a character over the * console. It returns the character printed on * success or -1 on error. * In : r0 - character to be printed * Out : return -1 on error else return character. * Clobber list : r1, r2 * --------------------------------------------- */ func console_putc ldr r2, =console_base ldr r1, [r2] b console_core_putc endfunc console_putc /* -------------------------------------------------------- * int console_core_putc(int c, uintptr_t base_addr) * Function to output a character over the console. It * returns the character printed on success or -1 on error. * In : r0 - character to be printed * r1 - console base address * Out : return -1 on error else return character. * Clobber list : r2 * -------------------------------------------------------- */ func console_core_putc /* Check the input parameter */ cmp r1, #0 beq putc_error /* Output specified character to UART shift-register */ str r0, [r1, #MXC_UART_TXD_OFFSET] /* Wait for transmit MXC_UART_STAT2_OFFSET.MXC_UART_STAT2_TXDC == 1 */ __putc_spin_ready: ldr r2, [r1, #MXC_UART_STAT2_OFFSET] ands r2, #MXC_UART_STAT2_TXDC beq __putc_spin_ready /* Transmit complete do we need to fixup \n to \n\r */ cmp r0, #10 beq __putc_fixup_lf /* No fixup necessary - exit here */ movs r0, #0 bx lr /* Fixup \n to \n\r */ __putc_fixup_lf: movs r0, #13 b console_core_putc putc_error: mov r0, #-1 bx lr endfunc console_core_putc /* --------------------------------------------- * int console_getc(void) * Function to get a character from the console. * It returns the character grabbed on success * or -1 on error. * Out : return -1 on error else return character. * Clobber list : r0, r1 * --------------------------------------------- */ func console_getc ldr r1, =console_base ldr r0, [r1] b console_core_getc endfunc console_getc /* --------------------------------------------- * int console_core_getc(void) * Function to get a character from the console. * It returns the character grabbed on success * or -1 on error. * In : r0 - console base address * Out : return -1 on error else return character. * Clobber list : r0, r1 * --------------------------------------------- */ func console_core_getc cmp r0, #0 beq getc_error 1: /* Check if the receive FIFO is empty */ /* TODO */ getc_error: mov r0, #-1 bx lr endfunc console_core_getc /* --------------------------------------------- * int console_flush(void) * Function to force a write of all buffered * data that hasn't been output. It returns 0 * upon successful completion, otherwise it * returns -1. * Clobber list : r0, r1 * --------------------------------------------- */ func console_flush ldr r1, =console_base ldr r0, [r1] b console_core_flush endfunc console_flush /* --------------------------------------------- * int console_core_flush(uintptr_t base_addr) * Function to force a write of all buffered * data that hasn't been output. * In : r0 - console base address * Out : return -1 on error else return 0. * Clobber list : r0, r1 * --------------------------------------------- */ func console_core_flush cmp r0, #0 beq flush_error 1: /* Loop while the transmit FIFO is busy */ /* TODO */ mov r0, #0 bx lr flush_error: mov r0, #-1 bx lr endfunc console_core_flush