diff options
Diffstat (limited to 'drivers/serial')
| -rw-r--r-- | drivers/serial/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/serial/arm_dcc.c | 63 |
2 files changed, 49 insertions, 25 deletions
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index fac317610e2..92d4212123d 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -119,6 +119,17 @@ config DEBUG_UART_UARTLITE You will need to provide parameters to make this work. The driver will be available until the real driver-model serial is running. +config DEBUG_UART_ARM_DCC + bool "ARM DCC" + help + Select this to enable a debug UART using the ARM JTAG DCC port. + The DCC port can be used for very early debugging and doesn't require + any additional setting like address/baudrate/clock. On systems without + any serial interface this is the easiest way how to get console. + Every ARM core has own DCC port which is the part of debug interface. + This port is available at least on ARMv6, ARMv7, ARMv8 and XScale + architectures. + config DEBUG_UART_ZYNQ bool "Xilinx Zynq" help diff --git a/drivers/serial/arm_dcc.c b/drivers/serial/arm_dcc.c index 4624666e8a2..07981e18ee4 100644 --- a/drivers/serial/arm_dcc.c +++ b/drivers/serial/arm_dcc.c @@ -1,6 +1,7 @@ /* * Copyright (C) 2004-2007 ARM Limited. * Copyright (C) 2008 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> + * Copyright (C) 2015 - 2016 Xilinx, Inc, Michal Simek * * SPDX-License-Identifier: GPL-2.0 * @@ -16,6 +17,7 @@ */ #include <common.h> +#include <dm.h> #include <serial.h> #if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V7) @@ -94,12 +96,7 @@ #define TIMEOUT_COUNT 0x4000000 -static int arm_dcc_init(void) -{ - return 0; -} - -static int arm_dcc_getc(void) +static int arm_dcc_getc(struct udevice *dev) { int ch; register unsigned int reg; @@ -112,7 +109,7 @@ static int arm_dcc_getc(void) return ch; } -static void arm_dcc_putc(char ch) +static int arm_dcc_putc(struct udevice *dev, char ch) { register unsigned int reg; unsigned int timeout_count = TIMEOUT_COUNT; @@ -123,41 +120,57 @@ static void arm_dcc_putc(char ch) break; } if (timeout_count == 0) - return; + return -EAGAIN; else write_dcc(ch); + + return 0; } -static int arm_dcc_tstc(void) +static int arm_dcc_pending(struct udevice *dev, bool input) { register unsigned int reg; - can_read_dcc(reg); + if (input) { + can_read_dcc(reg); + } else { + can_write_dcc(reg); + } return reg; } -static void arm_dcc_setbrg(void) -{ -} +static const struct dm_serial_ops arm_dcc_ops = { + .putc = arm_dcc_putc, + .pending = arm_dcc_pending, + .getc = arm_dcc_getc, +}; + +static const struct udevice_id arm_dcc_ids[] = { + { .compatible = "arm,dcc", }, + { } +}; -static struct serial_device arm_dcc_drv = { +U_BOOT_DRIVER(serial_dcc) = { .name = "arm_dcc", - .start = arm_dcc_init, - .stop = NULL, - .setbrg = arm_dcc_setbrg, - .putc = arm_dcc_putc, - .puts = default_serial_puts, - .getc = arm_dcc_getc, - .tstc = arm_dcc_tstc, + .id = UCLASS_SERIAL, + .of_match = arm_dcc_ids, + .ops = &arm_dcc_ops, + .flags = DM_FLAG_PRE_RELOC, }; -void arm_dcc_initialize(void) +#ifdef CONFIG_DEBUG_UART_ARM_DCC + +#include <debug_uart.h> + +static inline void _debug_uart_init(void) { - serial_register(&arm_dcc_drv); } -__weak struct serial_device *default_serial_console(void) +static inline void _debug_uart_putc(int ch) { - return &arm_dcc_drv; + arm_dcc_putc(NULL, ch); } + +DEBUG_UART_FUNCS +#endif |