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/*
* Copyright (c) 2016-2020, 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
* 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 r2, 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_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_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_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_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_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_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_BASE]
b console_pl011_core_getc
endfunc console_pl011_getc
/* ---------------------------------------------
* void 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 : void
* Clobber list : r0, r1
* ---------------------------------------------
*/
func console_pl011_core_flush
#if ENABLE_ASSERTIONS
cmp r0, #0
ASM_ASSERT(ne)
#endif /* ENABLE_ASSERTIONS */
1:
/* Loop while the transmit FIFO is busy */
ldr r1, [r0, #UARTFR]
tst r1, #PL011_UARTFR_BUSY
bne 1b
bx lr
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 : r0 - pointer to console_t structure
* Out : void
* 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_BASE]
b console_pl011_core_flush
endfunc console_pl011_flush
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