diff --git a/plat/nvidia/tegra/common/drivers/spe/shared_console.S b/plat/nvidia/tegra/common/drivers/spe/shared_console.S new file mode 100644 index 000000000..a9f0334f1 --- /dev/null +++ b/plat/nvidia/tegra/common/drivers/spe/shared_console.S @@ -0,0 +1,118 @@ +/* + * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ +#include + +#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_WRITE (CONSOLE_RING_DOORBELL | CONSOLE_FLUSH_DATA_TO_PORT) + + /* + * 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_core_init + .globl console_core_putc + .globl console_core_getc + .globl console_core_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: 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 + * ----------------------------------------------- + */ +func console_core_init + /* Check the input base address */ + cbz x0, core_init_fail + mov w0, #1 + ret +core_init_fail: + mov w0, wzr + ret +endfunc console_core_init + + /* -------------------------------------------------------- + * 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 : w0 - character to be printed + * x1 - console base address + * Out : return -1 on error else return character. + * Clobber list : x2 + * -------------------------------------------------------- + */ +func console_core_putc + /* Check the input parameter */ + cbz x1, putc_error + + /* wait until spe is ready */ +1: ldr w2, [x1] + and w2, w2, #CONSOLE_IS_BUSY + cbnz w2, 1b + + /* spe is ready */ + mov w2, w0 + and w2, w2, #0xFF + mov w3, #(CONSOLE_WRITE | (1 << CONSOLE_NUM_BYTES_SHIFT)) + orr w2, w2, w3 + str w2, [x1] + + ret +putc_error: + mov w0, #-1 + ret +endfunc console_core_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 : x0 - console base address + * Clobber list : x0, x1 + * --------------------------------------------- + */ +func console_core_getc + mov w0, #-1 + ret +endfunc console_core_getc + + /* --------------------------------------------- + * int console_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_core_flush + cbz x0, flush_error + + /* flush console */ + mov w1, #CONSOLE_WRITE + str w1, [x0] + mov w0, #0 + ret +flush_error: + mov w0, #-1 + ret +endfunc console_core_flush