blob: 9196c1cd1565a3568479b03de0dc59cc8b33b6e8 [file] [log] [blame]
/*
* Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
* Copyright (c) 2020, NVIDIA Corporation. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <asm_macros.S>
#include <console_macros.S>
#define CONSOLE_NUM_BYTES_SHIFT 24
#define CONSOLE_FLUSH_DATA_TO_PORT (1 << 26)
#define CONSOLE_RING_DOORBELL (1 << 31)
#define CONSOLE_IS_BUSY (1 << 31)
#define CONSOLE_TIMEOUT 0xC000 /* 50 ms */
/*
* This file contains a driver implementation to make use of the
* real console implementation provided by the SPE firmware running
* SoCs after Tegra186.
*
* This console is shared by multiple components and the SPE firmware
* finally displays everything on the UART port.
*/
.globl console_spe_core_init
.globl console_spe_core_putc
.globl console_spe_core_getc
.globl console_spe_core_flush
.globl console_spe_putc
.globl console_spe_getc
.globl console_spe_flush
.globl console_spe_register
.macro check_if_console_is_ready base, tmp1, tmp2, label
/* wait until spe is ready or timeout expires */
mrs \tmp2, cntps_tval_el1
1: ldr \tmp1, [\base]
and \tmp1, \tmp1, #CONSOLE_IS_BUSY
cbz \tmp1, 2f
mrs \tmp1, cntps_tval_el1
sub \tmp1, \tmp2, \tmp1
cmp \tmp1, #CONSOLE_TIMEOUT
b.lt 1b
b \label
2:
.endm
/* -------------------------------------------------
* int console_spe_register(uintptr_t baseaddr,
* uint32_t clock, uint32_t baud,
* console_t *console);
* Function to initialize and register a new spe
* 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_spe_register
/* Check the input base address */
cbz x0, register_fail
/* Dont use clock or baud rate, so ok to overwrite them */
check_if_console_is_ready x0, x1, x2, register_fail
cbz x3, register_fail
str x0, [x3, #CONSOLE_T_BASE]
mov x0, x3
finish_console_register spe putc=1, getc=1, flush=1
register_fail:
mov w0, wzr
ret
endfunc console_spe_register
/* --------------------------------------------------------
* int console_spe_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, x3
* --------------------------------------------------------
*/
func console_spe_core_putc
/* Check the input parameter */
cbz x1, putc_error
/* Prepend '\r' to '\n' */
cmp w0, #0xA
b.ne not_eol
check_if_console_is_ready x1, x2, x3, putc_error
/* spe is ready */
mov w2, #0xD /* '\r' */
and w2, w2, #0xFF
mov w3, #(CONSOLE_RING_DOORBELL | (1 << CONSOLE_NUM_BYTES_SHIFT))
orr w2, w2, w3
str w2, [x1]
not_eol:
check_if_console_is_ready x1, x2, x3, putc_error
/* spe is ready */
mov w2, w0
and w2, w2, #0xFF
mov w3, #(CONSOLE_RING_DOORBELL | (1 << CONSOLE_NUM_BYTES_SHIFT))
orr w2, w2, w3
str w2, [x1]
ret
putc_error:
mov w0, #-1
ret
endfunc console_spe_core_putc
/* --------------------------------------------------------
* int console_spe_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_spe_putc
ldr x1, [x1, #CONSOLE_T_BASE]
b console_spe_core_putc
endfunc console_spe_putc
/* ---------------------------------------------
* int console_spe_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_spe_getc
mov w0, #-1
ret
endfunc console_spe_getc
/* -------------------------------------------------
* int console_spe_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 : return -1 on error else return 0.
* Clobber list : x0, x1
* -------------------------------------------------
*/
func console_spe_core_flush
cbz x0, flush_error
/* flush console */
mov w1, #(CONSOLE_RING_DOORBELL | CONSOLE_FLUSH_DATA_TO_PORT)
str w1, [x0]
mov w0, #0
ret
flush_error:
mov w0, #-1
ret
endfunc console_spe_core_flush
/* ---------------------------------------------
* int console_spe_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 : return -1 on error else return 0.
* Clobber list : x0, x1
* ---------------------------------------------
*/
func console_spe_flush
ldr x0, [x0, #CONSOLE_T_BASE]
b console_spe_core_flush
endfunc console_spe_flush