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/*
* Copyright (c) 2013-2020, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <arch.h>
#include <asm_macros.S>
#include <assert_macros.S>
#include <console_macros.S>
#include <drivers/arm/pl011.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_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_pl011_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: x0 - console base address
* w1 - Uart clock in Hz
* w2 - Baud rate
* Out: return 1 on success else 0 on error
* Clobber list : x1, x2, x3, x4
* -----------------------------------------------
*/
func console_pl011_core_init
/* Check the input base address */
cbz x0, core_init_fail
#if !PL011_GENERIC_UART
/* Check baud rate and uart clock for sanity */
cbz w1, core_init_fail
cbz w2, core_init_fail
/* Disable uart before programming */
ldr w3, [x0, #UARTCR]
mov w4, #PL011_UARTCR_UARTEN
bic w3, w3, w4
str w3, [x0, #UARTCR]
/* Program the baudrate */
/* Divisor = (Uart clock * 4) / baudrate */
lsl w1, w1, #2
udiv w2, w1, w2
/* IBRD = Divisor >> 6 */
lsr w1, w2, #6
/* Write the IBRD */
str w1, [x0, #UARTIBRD]
/* FBRD = Divisor & 0x3F */
and w1, w2, #0x3f
/* Write the FBRD */
str w1, [x0, #UARTFBRD]
mov w1, #PL011_LINE_CONTROL
str w1, [x0, #UARTLCR_H]
/* Clear any pending errors */
str wzr, [x0, #UARTECR]
/* Enable tx, rx, and uart overall */
mov w1, #(PL011_UARTCR_RXE | PL011_UARTCR_TXE | PL011_UARTCR_UARTEN)
str w1, [x0, #UARTCR]
#endif
mov w0, #1
ret
core_init_fail:
mov w0, wzr
ret
endfunc console_pl011_core_init
.globl console_pl011_register
/* -----------------------------------------------
* int console_pl011_register(uintptr_t baseaddr,
* uint32_t clock, uint32_t baud,
* console_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: 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, x6, x7, x14
* -----------------------------------------------
*/
func console_pl011_register
mov x7, x30
mov x6, x3
cbz x6, register_fail
str x0, [x6, #CONSOLE_T_BASE]
bl console_pl011_core_init
cbz x0, register_fail
mov x0, x6
mov x30, x7
finish_console_register pl011 putc=1, getc=1, flush=1
register_fail:
ret x7
endfunc console_pl011_register
/* --------------------------------------------------------
* int console_pl011_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 : w0 - character to be printed
* x1 - console base address
* Out : return -1 on error else return character.
* Clobber list : x2
* --------------------------------------------------------
*/
func console_pl011_core_putc
#if ENABLE_ASSERTIONS
cmp x1, #0
ASM_ASSERT(ne)
#endif /* ENABLE_ASSERTIONS */
/* Prepend '\r' to '\n' */
cmp w0, #0xA
b.ne 2f
1:
/* Check if the transmit FIFO is full */
ldr w2, [x1, #UARTFR]
tbnz w2, #PL011_UARTFR_TXFF_BIT, 1b
mov w2, #0xD
str w2, [x1, #UARTDR]
2:
/* Check if the transmit FIFO is full */
ldr w2, [x1, #UARTFR]
tbnz w2, #PL011_UARTFR_TXFF_BIT, 2b
str w0, [x1, #UARTDR]
ret
endfunc console_pl011_core_putc
/* --------------------------------------------------------
* int console_pl011_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_pl011_putc
#if ENABLE_ASSERTIONS
cmp x1, #0
ASM_ASSERT(ne)
#endif /* ENABLE_ASSERTIONS */
ldr x1, [x1, #CONSOLE_T_BASE]
b console_pl011_core_putc
endfunc console_pl011_putc
/* ---------------------------------------------
* int console_pl011_core_getc(uintptr_t base_addr)
* Function to get a character from the console.
* It returns the character grabbed on success
* or -1 if no character is available.
* In : x0 - console base address
* Out: w0 - character if available, else -1
* Clobber list : x0, x1
* ---------------------------------------------
*/
func console_pl011_core_getc
#if ENABLE_ASSERTIONS
cmp x0, #0
ASM_ASSERT(ne)
#endif /* ENABLE_ASSERTIONS */
/* Check if the receive FIFO is empty */
ldr w1, [x0, #UARTFR]
tbnz w1, #PL011_UARTFR_RXFE_BIT, no_char
ldr w1, [x0, #UARTDR]
mov w0, w1
ret
no_char:
mov w0, #ERROR_NO_PENDING_CHAR
ret
endfunc console_pl011_core_getc
/* ---------------------------------------------
* int console_pl011_getc(console_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 : x0 - pointer to console_t structure
* Out: w0 - character if available, else -1
* Clobber list : x0, x1
* ---------------------------------------------
*/
func console_pl011_getc
#if ENABLE_ASSERTIONS
cmp x0, #0
ASM_ASSERT(ne)
#endif /* ENABLE_ASSERTIONS */
ldr x0, [x0, #CONSOLE_T_BASE]
b console_pl011_core_getc
endfunc console_pl011_getc
/* ---------------------------------------------
* void console_pl011_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_pl011_core_flush
#if ENABLE_ASSERTIONS
cmp x0, #0
ASM_ASSERT(ne)
#endif /* ENABLE_ASSERTIONS */
1:
/* Loop until the transmit FIFO is empty */
ldr w1, [x0, #UARTFR]
tbnz w1, #PL011_UARTFR_BUSY_BIT, 1b
ret
endfunc console_pl011_core_flush
/* ---------------------------------------------
* void console_pl011_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_pl011_flush
#if ENABLE_ASSERTIONS
cmp x0, #0
ASM_ASSERT(ne)
#endif /* ENABLE_ASSERTIONS */
ldr x0, [x0, #CONSOLE_T_BASE]
b console_pl011_core_flush
endfunc console_pl011_flush
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