Patrick Georgi (pgeorgi@google.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/9765
-gerrit
commit b4cc32b496adb435ceeb0ef189ede669747afc91 Author: Daisuke Nojiri dnojiri@chromium.org Date: Fri Jan 23 10:02:24 2015 -0800
purin: add ns16550 driver
BUG=chrome-os-partner:35807 BRANCH=broadcom-firmware TEST=booted b0 board. messages printed on console:
coreboot-bcf5dc0-dirty bootblock Mon Feb 9 13:33:55 PST 2015 starting... Exception handlers installed.
Change-Id: I271ead2f4fe48b809fd311acd5a27a675dce549e Signed-off-by: Patrick Georgi pgeorgi@chromium.org Original-Commit-Id: ddff8fb170e775a121150fce065410d2925ad18c Original-Signed-off-by: Daisuke Nojiri dnojiri@chromium.org Original-Change-Id: Ia6e82fa89547d61745c1473f723897dc3c1296ef Original-Reviewed-on: https://chromium-review.googlesource.com/251301 Original-Reviewed-by: Julius Werner jwerner@chromium.org --- src/soc/broadcom/cygnus/Kconfig | 5 + src/soc/broadcom/cygnus/Makefile.inc | 12 +- src/soc/broadcom/cygnus/include/soc/ns16550.h | 133 ++++------ src/soc/broadcom/cygnus/ns16550.c | 346 +++++++------------------- src/soc/broadcom/cygnus/uart.c | 42 ---- 5 files changed, 151 insertions(+), 387 deletions(-)
diff --git a/src/soc/broadcom/cygnus/Kconfig b/src/soc/broadcom/cygnus/Kconfig index 158f61c..2ccc306 100644 --- a/src/soc/broadcom/cygnus/Kconfig +++ b/src/soc/broadcom/cygnus/Kconfig @@ -39,4 +39,9 @@ config BOOTBLOCK_CPU_INIT string default "soc/broadcom/cygnus/bootblock.c"
+config CONSOLE_SERIAL_UART_ADDRESS + hex + depends on CONSOLE_SERIAL_UART + default 0x18023000 + endif diff --git a/src/soc/broadcom/cygnus/Makefile.inc b/src/soc/broadcom/cygnus/Makefile.inc index dea6cef..b7012ea 100644 --- a/src/soc/broadcom/cygnus/Makefile.inc +++ b/src/soc/broadcom/cygnus/Makefile.inc @@ -1,7 +1,7 @@ ## ## This file is part of the coreboot project. ## -## Copyright 2014 Google Inc. +## Copyright 2015 Google Inc. ## ## This program is free software; you can redistribute it and/or modify ## it under the terms of the GNU General Public License as published by @@ -22,13 +22,15 @@ bootblock-y += cbmem.c bootblock-y += i2c.c bootblock-y += timer.c bootblock-$(CONFIG_SPI_FLASH) += spi.c -bootblock-$(CONFIG_CONSOLE_SERIAL) += uart.c +ifeq ($(CONFIG_BOOTBLOCK_CONSOLE),y) +bootblock-$(CONFIG_DRIVERS_UART) += ns16550.c +endif
verstage-y += verstage.c verstage-y += i2c.c verstage-y += timer.c verstage-$(CONFIG_SPI_FLASH) += spi.c -verstage-$(CONFIG_CONSOLE_SERIAL) += uart.c +verstage-$(CONFIG_DRIVERS_UART) += ns16550.c
romstage-y += cbmem.c romstage-y += i2c.c @@ -36,13 +38,13 @@ romstage-y += timer.c romstage-y += romstage.c romstage-y += sdram.c romstage-$(CONFIG_SPI_FLASH) += spi.c -romstage-$(CONFIG_CONSOLE_SERIAL) += uart.c +romstage-$(CONFIG_DRIVERS_UART) += ns16550.c
ramstage-y += cbmem.c ramstage-y += i2c.c ramstage-y += timer.c ramstage-$(CONFIG_SPI_FLASH) += spi.c -ramstage-$(CONFIG_CONSOLE_SERIAL) += uart.c +ramstage-$(CONFIG_DRIVERS_UART) += ns16550.c
CPPFLAGS_common += -Isrc/soc/broadcom/cygnus/include/
diff --git a/src/soc/broadcom/cygnus/include/soc/ns16550.h b/src/soc/broadcom/cygnus/include/soc/ns16550.h index 51cb5b4..12e53c1 100644 --- a/src/soc/broadcom/cygnus/include/soc/ns16550.h +++ b/src/soc/broadcom/cygnus/include/soc/ns16550.h @@ -1,81 +1,61 @@ /* - * NS16550 Serial Port - * originally from linux source (arch/powerpc/boot/ns16550.h) + * This file is part of the coreboot project. * - * Cleanup and unification - * (C) 2009 by Detlev Zundel, DENX Software Engineering GmbH + * Copyright (C) 2000 Flying Pig Systems + * Copyright (C) 2005 Wind River Systems + * Copyright (C) 2009 DENX Software Engineering GmbH + * Copyright (C) 2015 Google Inc. * - * modified slightly to - * have addresses as offsets from CONFIG_SYS_ISA_BASE - * added a few more definitions - * added prototypes for ns16550.c - * reduced no of com ports to 2 - * modifications (c) Rob Taylor, Flying Pig Systems. 2000. + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. * - * added support for port on 64-bit bus - * by Richard Danter (richard.danter@windriver.com), (C) 2005 Wind River Systems - */ - -/* - * Note that the following macro magic uses the fact that the compiler - * will not allocate storage for arrays of size 0 + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
-#include <linux/types.h> - -#if !defined(CONFIG_SYS_NS16550_REG_SIZE) || (CONFIG_SYS_NS16550_REG_SIZE == 0) -#error "Please define NS16550 registers size." -#elif defined(CONFIG_SYS_NS16550_MEM32) -#define UART_REG(x) u32 x -#elif (CONFIG_SYS_NS16550_REG_SIZE > 0) -#define UART_REG(x) \ - unsigned char prepad_##x[CONFIG_SYS_NS16550_REG_SIZE - 1]; \ - unsigned char x; -#elif (CONFIG_SYS_NS16550_REG_SIZE < 0) -#define UART_REG(x) \ - unsigned char x; \ - unsigned char postpad_##x[-CONFIG_SYS_NS16550_REG_SIZE - 1]; -#endif - -struct NS16550 { - UART_REG(rbr); /* 0 */ - UART_REG(ier); /* 1 */ - UART_REG(fcr); /* 2 */ - UART_REG(lcr); /* 3 */ - UART_REG(mcr); /* 4 */ - UART_REG(lsr); /* 5 */ - UART_REG(msr); /* 6 */ - UART_REG(spr); /* 7 */ -#ifdef CONFIG_SOC_DA8XX - UART_REG(reg8); /* 8 */ - UART_REG(reg9); /* 9 */ - UART_REG(revid1); /* A */ - UART_REG(revid2); /* B */ - UART_REG(pwr_mgmt); /* C */ - UART_REG(mdr1); /* D */ -#else - UART_REG(mdr1); /* 8 */ - UART_REG(reg9); /* 9 */ - UART_REG(regA); /* A */ - UART_REG(regB); /* B */ - UART_REG(regC); /* C */ - UART_REG(regD); /* D */ - UART_REG(regE); /* E */ - UART_REG(uasr); /* F */ - UART_REG(scr); /* 10*/ - UART_REG(ssr); /* 11*/ - UART_REG(reg12); /* 12*/ - UART_REG(osc_12m_sel); /* 13*/ -#endif +#include <stdint.h> + +struct ns16550 { + union { + uint32_t thr; /* Transmit holding register. */ + uint32_t rbr; /* Receive buffer register. */ + uint32_t dll; /* Divisor latch lsb. */ + }; + union { + uint32_t ier; /* Interrupt enable register. */ + uint32_t dlm; /* Divisor latch msb. */ + }; + union { + uint32_t iir; /* Interrupt identification register. */ + uint32_t fcr; /* FIFO control register. */ + }; + uint32_t lcr; /* 3 */ + uint32_t mcr; /* 4 */ + uint32_t lsr; /* 5 */ + uint32_t msr; /* 6 */ + uint32_t spr; /* 7 */ + uint32_t mdr1; /* 8 */ + uint32_t reg9; /* 9 */ + uint32_t regA; /* A */ + uint32_t regB; /* B */ + uint32_t regC; /* C */ + uint32_t regD; /* D */ + uint32_t regE; /* E */ + uint32_t uasr; /* F */ + uint32_t scr; /* 10*/ + uint32_t ssr; /* 11*/ + uint32_t reg12; /* 12*/ + uint32_t osc_12m_sel; /* 13*/ };
-#define thr rbr -#define iir fcr -#define dll rbr -#define dlm ier - -typedef struct NS16550 *NS16550_t; - /* * These are the definitions for the FIFO Control Register */ @@ -163,16 +143,5 @@ typedef struct NS16550 *NS16550_t; #define UART_IER_THRI 0x02 /* Enable Transmitter holding register int. */ #define UART_IER_RDI 0x01 /* Enable receiver data interrupt */
- -#ifdef CONFIG_OMAP1510 -#define OSC_12M_SEL 0x01 /* selects 6.5 * current clk div */ -#endif - -/* useful defaults for LCR */ +/* useful defaults for LCR: 8 data, 1 stop, no parity */ #define UART_LCR_8N1 0x03 - -void NS16550_init(NS16550_t com_port, int baud_divisor); -void NS16550_putc(NS16550_t com_port, char c); -char NS16550_getc(NS16550_t com_port); -int NS16550_tstc(NS16550_t com_port); -void NS16550_reinit(NS16550_t com_port, int baud_divisor); diff --git a/src/soc/broadcom/cygnus/ns16550.c b/src/soc/broadcom/cygnus/ns16550.c index cbb32e0..d1ef843 100644 --- a/src/soc/broadcom/cygnus/ns16550.c +++ b/src/soc/broadcom/cygnus/ns16550.c @@ -1,301 +1,131 @@ /* - * (C) Copyright 2000 - * Rob Taylor, Flying Pig Systems. robt@flyingpig.com. + * This file is part of the coreboot project. * - * SPDX-License-Identifier: GPL-2.0+ - */ - -#include <common.h> -#include <linux/compiler.h> - -#include <ns16550.h> -#ifdef CONFIG_NS87308 -#include <ns87308.h> -#endif - -#include <serial.h> - -#ifndef CONFIG_NS16550_MIN_FUNCTIONS - -DECLARE_GLOBAL_DATA_PTR; - -#if !defined(CONFIG_CONS_INDEX) -#elif (CONFIG_CONS_INDEX < 1) || (CONFIG_CONS_INDEX > 6) -#error "Invalid console index value." -#endif - -#if CONFIG_CONS_INDEX == 1 && !defined(CONFIG_SYS_NS16550_COM1) -#error "Console port 1 defined but not configured." -#elif CONFIG_CONS_INDEX == 2 && !defined(CONFIG_SYS_NS16550_COM2) -#error "Console port 2 defined but not configured." -#elif CONFIG_CONS_INDEX == 3 && !defined(CONFIG_SYS_NS16550_COM3) -#error "Console port 3 defined but not configured." -#elif CONFIG_CONS_INDEX == 4 && !defined(CONFIG_SYS_NS16550_COM4) -#error "Console port 4 defined but not configured." -#elif CONFIG_CONS_INDEX == 5 && !defined(CONFIG_SYS_NS16550_COM5) -#error "Console port 5 defined but not configured." -#elif CONFIG_CONS_INDEX == 6 && !defined(CONFIG_SYS_NS16550_COM6) -#error "Console port 6 defined but not configured." -#endif - -/* Note: The port number specified in the functions is 1 based. - * the array is 0 based. + * Copyright (C) 2000 Rob Taylor, Flying Pig Systems. robt@flyingpig.com. + * Copyright (C) Broadcom Corporation + * Copyright (C) 2015 Google Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ -static NS16550_t serial_ports[6] = { -#ifdef CONFIG_SYS_NS16550_COM1 - (NS16550_t)CONFIG_SYS_NS16550_COM1, -#else - NULL, -#endif -#ifdef CONFIG_SYS_NS16550_COM2 - (NS16550_t)CONFIG_SYS_NS16550_COM2, -#else - NULL, -#endif -#ifdef CONFIG_SYS_NS16550_COM3 - (NS16550_t)CONFIG_SYS_NS16550_COM3, -#else - NULL, -#endif -#ifdef CONFIG_SYS_NS16550_COM4 - (NS16550_t)CONFIG_SYS_NS16550_COM4, -#else - NULL, -#endif -#ifdef CONFIG_SYS_NS16550_COM5 - (NS16550_t)CONFIG_SYS_NS16550_COM5, -#else - NULL, -#endif -#ifdef CONFIG_SYS_NS16550_COM6 - (NS16550_t)CONFIG_SYS_NS16550_COM6 -#else - NULL -#endif -};
-#define PORT serial_ports[port-1] +#include <arch/io.h> +#include <boot/coreboot_tables.h> +#include <console/console.h> /* for __console definition */ +#include <console/uart.h> +#include <delay.h> +#include <soc/ns16550.h>
-/* Multi serial device functions */ -#define DECLARE_ESERIAL_FUNCTIONS(port) \ - static int eserial##port##_init(void) \ - { \ - int clock_divisor; \ - clock_divisor = calc_divisor(serial_ports[port-1]); \ - NS16550_init(serial_ports[port-1], clock_divisor); \ - return 0 ; \ - } \ - static void eserial##port##_setbrg(void) \ - { \ - serial_setbrg_dev(port); \ - } \ - static int eserial##port##_getc(void) \ - { \ - return serial_getc_dev(port); \ - } \ - static int eserial##port##_tstc(void) \ - { \ - return serial_tstc_dev(port); \ - } \ - static void eserial##port##_putc(const char c) \ - { \ - serial_putc_dev(port, c); \ - } \ - static void eserial##port##_puts(const char *s) \ - { \ - serial_puts_dev(port, s); \ - } +#define SYS_NS16550_CLK 100000000 +#define SYS_NS16550_BAUDRATE 115200 +#define MODE_X_DIV 16 +#define SINGLE_CHAR_TIMEOUT (50 * 1000)
-/* Serial device descriptor */ -#define INIT_ESERIAL_STRUCTURE(port, __name) { \ - .name = __name, \ - .start = eserial##port##_init, \ - .stop = NULL, \ - .setbrg = eserial##port##_setbrg, \ - .getc = eserial##port##_getc, \ - .tstc = eserial##port##_tstc, \ - .putc = eserial##port##_putc, \ - .puts = eserial##port##_puts, \ -} +static struct ns16550 * const regs = + (void *)CONFIG_CONSOLE_SERIAL_UART_ADDRESS;
-int calc_divisor(NS16550_t port) +static int calc_divisor(void) { -#ifdef CONFIG_OMAP1510 - /* If can't cleanly clock 115200 set div to 1 */ - if ((CONFIG_SYS_NS16550_CLK == 12000000) && (gd->baudrate == 115200)) { - port->osc_12m_sel = OSC_12M_SEL; /* enable 6.5 * divisor */ - return (1); /* return 1 for base divisor */ - } - port->osc_12m_sel = 0; /* clear if previsouly set */ -#endif -#ifdef CONFIG_OMAP1610 - /* If can't cleanly clock 115200 set div to 1 */ - if ((CONFIG_SYS_NS16550_CLK == 48000000) && (gd->baudrate == 115200)) { - return (26); /* return 26 for base divisor */ - } -#endif - -#define MODE_X_DIV 16 /* Compute divisor value. Normally, we should simply return: - * CONFIG_SYS_NS16550_CLK) / MODE_X_DIV / gd->baudrate + * ns16550_clk / MODE_X_DIV / baudrate * but we need to round that value by adding 0.5. * Rounding is especially important at high baud rates. */ - return (CONFIG_SYS_NS16550_CLK + (gd->baudrate * (MODE_X_DIV / 2))) / - (MODE_X_DIV * gd->baudrate); + int div = MODE_X_DIV * SYS_NS16550_BAUDRATE; + return (SYS_NS16550_CLK + div / 2) / div; }
-void -_serial_putc(const char c,const int port) +static void ns16550_init(void) { - if (c == '\n') - NS16550_putc(PORT, '\r'); - - NS16550_putc(PORT, c); -} - -void -_serial_putc_raw(const char c,const int port) + int baud_divisor = calc_divisor(); + + while (!(readl(®s->lsr) & UART_LSR_TEMT)) + ; + + writel(0, ®s->ier); + writel(UART_LCR_BKSE | UART_LCR_8N1, ®s->lcr); + writel(0, ®s->dll); + writel(0, ®s->dlm); + writel(UART_LCR_8N1, ®s->lcr); + writel(UART_MCR_DTR | UART_MCR_RTS, ®s->mcr); + /* clear & enable FIFOs */ + writel(UART_FCR_FIFO_EN | UART_FCR_RXSR | UART_FCR_TXSR, ®s->fcr); + writel(UART_LCR_BKSE | UART_LCR_8N1, ®s->lcr); + writel(baud_divisor & 0xff, ®s->dll); + writel((baud_divisor >> 8) & 0xff, ®s->dlm); + writel(UART_LCR_8N1, ®s->lcr); +} + +static void ns16550_tx_byte(unsigned char data) { - NS16550_putc(PORT, c); + while ((readl(®s->lsr) & UART_LSR_THRE) == 0) + ; + writel(data, ®s->thr); }
-void -_serial_puts (const char *s,const int port) +static void ns16550_tx_flush(void) { - while (*s) { - _serial_putc (*s++,port); - } + while (!(readl(®s->lsr) & UART_LSR_TEMT)) + ; }
- -int -_serial_getc(const int port) +static int ns16550_tst_byte(void) { - return NS16550_getc(PORT); + return (readl(®s->lsr) & UART_LSR_DR) != 0; }
-int -_serial_tstc(const int port) +static unsigned char ns16550_rx_byte(void) { - return NS16550_tstc(PORT); + unsigned long int i = SINGLE_CHAR_TIMEOUT; + while (i-- && !ns16550_tst_byte()) + udelay(1); + if (i) + return readl(®s->rbr); + else + return 0x0; }
-void -_serial_setbrg (const int port) +void uart_init(int idx) { - int clock_divisor; - - clock_divisor = calc_divisor(PORT); - NS16550_reinit(PORT, clock_divisor); + ns16550_init(); }
-static inline void -serial_putc_dev(unsigned int dev_index,const char c) +void uart_tx_byte(int idx, unsigned char data) { - _serial_putc(c,dev_index); + ns16550_tx_byte(data); }
-static inline void -serial_putc_raw_dev(unsigned int dev_index,const char c) +void uart_tx_flush(int idx) { - _serial_putc_raw(c,dev_index); + ns16550_tx_flush(); }
-static inline void -serial_puts_dev(unsigned int dev_index,const char *s) +unsigned char uart_rx_byte(int idx) { - _serial_puts(s,dev_index); + return ns16550_rx_byte(); }
-static inline int -serial_getc_dev(unsigned int dev_index) +#ifndef __PRE_RAM__ +void uart_fill_lb(void *data) { - return _serial_getc(dev_index); -} + struct lb_serial serial; + serial.type = LB_SERIAL_TYPE_MEMORY_MAPPED; + serial.baseaddr = (uintptr_t)regs; + serial.baud = default_baudrate(); + serial.regwidth = 1; + lb_add_serial(&serial, data);
-static inline int -serial_tstc_dev(unsigned int dev_index) -{ - return _serial_tstc(dev_index); -} - -static inline void -serial_setbrg_dev(unsigned int dev_index) -{ - _serial_setbrg(dev_index); + lb_add_console(LB_TAG_CONSOLE_SERIAL8250MEM, data); } - -#if defined(CONFIG_SYS_NS16550_COM1) -DECLARE_ESERIAL_FUNCTIONS(1); -struct serial_device eserial1_device = - INIT_ESERIAL_STRUCTURE(1, "eserial0"); -#endif -#if defined(CONFIG_SYS_NS16550_COM2) -DECLARE_ESERIAL_FUNCTIONS(2); -struct serial_device eserial2_device = - INIT_ESERIAL_STRUCTURE(2, "eserial1"); -#endif -#if defined(CONFIG_SYS_NS16550_COM3) -DECLARE_ESERIAL_FUNCTIONS(3); -struct serial_device eserial3_device = - INIT_ESERIAL_STRUCTURE(3, "eserial2"); -#endif -#if defined(CONFIG_SYS_NS16550_COM4) -DECLARE_ESERIAL_FUNCTIONS(4); -struct serial_device eserial4_device = - INIT_ESERIAL_STRUCTURE(4, "eserial3"); #endif -#if defined(CONFIG_SYS_NS16550_COM5) -DECLARE_ESERIAL_FUNCTIONS(5); -struct serial_device eserial5_device = - INIT_ESERIAL_STRUCTURE(5, "eserial4"); -#endif -#if defined(CONFIG_SYS_NS16550_COM6) -DECLARE_ESERIAL_FUNCTIONS(6); -struct serial_device eserial6_device = - INIT_ESERIAL_STRUCTURE(6, "eserial5"); -#endif - -__weak struct serial_device *default_serial_console(void) -{ -#if CONFIG_CONS_INDEX == 1 - return &eserial1_device; -#elif CONFIG_CONS_INDEX == 2 - return &eserial2_device; -#elif CONFIG_CONS_INDEX == 3 - return &eserial3_device; -#elif CONFIG_CONS_INDEX == 4 - return &eserial4_device; -#elif CONFIG_CONS_INDEX == 5 - return &eserial5_device; -#elif CONFIG_CONS_INDEX == 6 - return &eserial6_device; -#else -#error "Bad CONFIG_CONS_INDEX." -#endif -} - -void ns16550_serial_initialize(void) -{ -#if defined(CONFIG_SYS_NS16550_COM1) - serial_register(&eserial1_device); -#endif -#if defined(CONFIG_SYS_NS16550_COM2) - serial_register(&eserial2_device); -#endif -#if defined(CONFIG_SYS_NS16550_COM3) - serial_register(&eserial3_device); -#endif -#if defined(CONFIG_SYS_NS16550_COM4) - serial_register(&eserial4_device); -#endif -#if defined(CONFIG_SYS_NS16550_COM5) - serial_register(&eserial5_device); -#endif -#if defined(CONFIG_SYS_NS16550_COM6) - serial_register(&eserial6_device); -#endif -} - -#endif /* !CONFIG_NS16550_MIN_FUNCTIONS */ diff --git a/src/soc/broadcom/cygnus/uart.c b/src/soc/broadcom/cygnus/uart.c deleted file mode 100644 index 70b4a2e..0000000 --- a/src/soc/broadcom/cygnus/uart.c +++ /dev/null @@ -1,42 +0,0 @@ -/* - * This file is part of the coreboot project. - * - * Copyright 2015 Google Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; version 2 of the License. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#include <boot/coreboot_tables.h> -#include <console/uart.h> - -void uart_init(int idx) -{ -} - -void uart_tx_byte(int idx, unsigned char data) -{ -} - -void uart_tx_flush(int idx) -{ -} - -unsigned char uart_rx_byte(int idx) -{ - return '\0'; -} - -void uart_fill_lb(void *data) -{ -}