/* * Copyright (c) 2016-2019, ARM Limited and Contributors. All rights reserved. * * SPDX-License-Identifier: BSD-3-Clause */ #include #include #include #include #include /* * "core" functions are low-level implementations that don't require * writeable memory and are thus safe to call in BL1 crash context. */ .globl console_pl011_core_init .globl console_pl011_core_putc .globl console_pl011_core_getc .globl console_pl011_core_flush .globl console_pl011_putc .globl console_pl011_getc .globl console_pl011_flush /* ----------------------------------------------- * 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 * ----------------------------------------------- */ func console_pl011_core_init /* Check the input base address */ cmp r0, #0 beq core_init_fail #if !PL011_GENERIC_UART /* Check baud rate and uart clock for sanity */ cmp r1, #0 beq core_init_fail cmp r2, #0 beq core_init_fail /* Disable the UART before initialization */ ldr r3, [r0, #UARTCR] bic r3, r3, #PL011_UARTCR_UARTEN str r3, [r0, #UARTCR] /* Program the baudrate */ /* Divisor = (Uart clock * 4) / baudrate */ lsl r1, r1, #2 #if (ARM_ARCH_MAJOR == 7) && !defined(ARMV7_SUPPORTS_VIRTUALIZATION) push {r0,r3} softudiv r0,r1,r2,r3 mov r1, r0 pop {r0,r3} #else udiv r2, r1, r2 #endif /* IBRD = Divisor >> 6 */ lsr r1, r2, #6 /* Write the IBRD */ str r1, [r0, #UARTIBRD] /* FBRD = Divisor & 0x3F */ and r1, r2, #0x3f /* Write the FBRD */ str r1, [r0, #UARTFBRD] mov r1, #PL011_LINE_CONTROL str r1, [r0, #UARTLCR_H] /* Clear any pending errors */ mov r1, #0 str r1, [r0, #UARTECR] /* Enable tx, rx, and uart overall */ ldr r1, =(PL011_UARTCR_RXE | PL011_UARTCR_TXE | PL011_UARTCR_UARTEN) str r1, [r0, #UARTCR] #endif mov r0, #1 bx lr core_init_fail: mov r0, #0 bx lr endfunc console_pl011_core_init .globl console_pl011_register /* ------------------------------------------------------- * int console_pl011_register(uintptr_t baseaddr, * uint32_t clock, uint32_t baud, * console_pl011_t *console); * Function to initialize and register a new PL011 * console. Storage passed in for the console struct * *must* be persistent (i.e. not from the stack). * In: r0 - UART register base address * r1 - UART clock in Hz * r2 - Baud rate * r3 - pointer to empty console_pl011_t struct * Out: return 1 on success, 0 on error * Clobber list : r0, r1, r2 * ------------------------------------------------------- */ func console_pl011_register push {r4, lr} mov r4, r3 cmp r4, #0 beq register_fail str r0, [r4, #CONSOLE_T_PL011_BASE] bl console_pl011_core_init cmp r0, #0 beq register_fail mov r0, r4 pop {r4, lr} finish_console_register pl011 putc=1, getc=1, flush=1 register_fail: pop {r4, pc} endfunc console_pl011_register /* -------------------------------------------------------- * 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_pl011_core_putc /* Check the input parameter */ cmp r1, #0 beq putc_error /* Prepend '\r' to '\n' */ cmp r0, #0xA bne 2f 1: /* Check if the transmit FIFO is full */ ldr r2, [r1, #UARTFR] tst r2, #PL011_UARTFR_TXFF bne 1b mov r2, #0xD str r2, [r1, #UARTDR] 2: /* Check if the transmit FIFO is full */ ldr r2, [r1, #UARTFR] tst r2, #PL011_UARTFR_TXFF bne 2b str r0, [r1, #UARTDR] bx lr putc_error: mov r0, #-1 bx lr endfunc console_pl011_core_putc /* -------------------------------------------------------- * int console_pl011_putc(int c, console_pl011_t *console) * 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 - pointer to console_t structure * Out : return -1 on error else return character. * Clobber list: r2 * ------------------------------------------------------- */ func console_pl011_putc #if ENABLE_ASSERTIONS cmp r1, #0 ASM_ASSERT(ne) #endif /* ENABLE_ASSERTIONS */ ldr r1, [r1, #CONSOLE_T_PL011_BASE] b console_pl011_core_putc endfunc console_pl011_putc /* --------------------------------------------- * int console_core_getc(uintptr_t base_addr) * Function to get a character from the console. * It returns the character grabbed on success * or -1 on error. * In : r0 - console base address * Clobber list : r0, r1 * --------------------------------------------- */ func console_pl011_core_getc cmp r0, #0 beq getc_error 1: /* Check if the receive FIFO is empty */ ldr r1, [r0, #UARTFR] tst r1, #PL011_UARTFR_RXFE bne 1b ldr r1, [r0, #UARTDR] mov r0, r1 bx lr getc_error: mov r0, #-1 bx lr endfunc console_pl011_core_getc /* ------------------------------------------------ * int console_pl011_getc(console_pl011_t *console) * Function to get a character from the console. * It returns the character grabbed on success * or -1 if no character is available. * In : r0 - pointer to console_t structure * Out: r0 - character if available, else -1 * Clobber list: r0, r1 * ------------------------------------------------ */ func console_pl011_getc #if ENABLE_ASSERTIONS cmp r0, #0 ASM_ASSERT(ne) #endif /* ENABLE_ASSERTIONS */ ldr r0, [r0, #CONSOLE_T_PL011_BASE] b console_pl011_core_getc endfunc console_pl011_getc /* --------------------------------------------- * 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_pl011_core_flush cmp r0, #0 beq flush_error 1: /* Loop while the transmit FIFO is busy */ ldr r1, [r0, #UARTFR] tst r1, #PL011_UARTFR_BUSY bne 1b mov r0, #0 bx lr flush_error: mov r0, #-1 bx lr endfunc console_pl011_core_flush /* --------------------------------------------- * int console_pl011_flush(console_pl011_t *console) * Function to force a write of all buffered * data that hasn't been output. * In : r0 - pointer to console_t structure * Out : return -1 on error else return 0. * Clobber list: r0, r1 * --------------------------------------------- */ func console_pl011_flush #if ENABLE_ASSERTIONS cmp r0, #0 ASM_ASSERT(ne) #endif /* ENABLE_ASSERTIONS */ ldr r0, [r0, #CONSOLE_T_PL011_BASE] b console_pl011_core_flush endfunc console_pl011_flush