This introduces support for NS16550 and related OMAP support. This driver is a port from Uboot v1 driver from OMAP's Uboot tree. OMAP U-Boot V1 source is available here: http://linux.omap.com/pub/bootloader/3430sdp/u-boot-v1.tar.gz
Signed-off-by: Nishanth Menonx0nishan@ti.com
--- drivers/serial/Kconfig | 42 ++++++ drivers/serial/Makefile | 1 drivers/serial/serial_ns16550.c | 248 ++++++++++++++++++++++++++++++++++++++++ drivers/serial/serial_ns16550.h | 183 +++++++++++++++++++++++++++++ include/ns16550.h | 46 +++++++ 5 files changed, 520 insertions(+)
Index: u-boot-v2.git/drivers/serial/Kconfig =================================================================== --- u-boot-v2.git.orig/drivers/serial/Kconfig 2008-05-20 17:59:26.000000000 -0500 +++ u-boot-v2.git/drivers/serial/Kconfig 2008-05-20 18:02:28.000000000 -0500 @@ -24,4 +24,46 @@ depends on BLACKFIN default y bool "Blackfin serial driver" + +config DRIVER_SERIAL_NS16550 + default n + bool "NS16550 serial driver" + help + Enable this to get support for NS16550 based serial devices +choice + prompt "NS16550 register size" + depends on DRIVER_SERIAL_NS16550 + +config DRIVER_SERIAL_NS16550_REG_SIZE_8_BITS + bool "8 bit register" + help + Say Y here if you are using a 8 bit register for NS16550 + +config DRIVER_SERIAL_NS16550_REG_SIZE_16_BITS + bool "16 bit register" + help + Say Y here if you are using a 16 bit register for NS16550 + +config DRIVER_SERIAL_NS16550_REG_SIZE_32_BITS + bool "32 bit register" + help + Say Y here if you are using a 32 bit register for NS16550 + +config DRIVER_SERIAL_NS16550_REG_SIZE_8_BITS_PAD_TO_32 + bool "8 bit register Padded to 32 bit" + help + Say Y here if you are using a 8 bit register padded to 32 bits for NS16550 + +config DRIVER_SERIAL_NS16550_REG_SIZE_8_BITS_PAD_TO_64 + bool "8 bit register Padded to 64 bit" + help + Say Y here if you are using a 8 bit register padded to 64 bits for NS16550 +endchoice + +config DRIVER_SERIAL_NS16550_OMAP_EXTENSIONS + bool "OMAP Extensions for NS16550" + depends on DRIVER_SERIAL_NS16550 + depends on ARCH_OMAP + help + Say Y here if you are using OMAP extensions to NS16550 endmenu Index: u-boot-v2.git/drivers/serial/Makefile =================================================================== --- u-boot-v2.git.orig/drivers/serial/Makefile 2008-05-20 17:59:25.000000000 -0500 +++ u-boot-v2.git/drivers/serial/Makefile 2008-05-20 18:02:28.000000000 -0500 @@ -10,3 +10,4 @@ obj-$(CONFIG_DRIVER_SERIAL_LINUX_COMSOLE) += linux_console.o obj-$(CONFIG_DRIVER_SERIAL_MPC5XXX) += serial_mpc5xxx.o obj-$(CONFIG_DRIVER_SERIAL_BLACKFIN) += serial_blackfin.o +obj-$(CONFIG_DRIVER_SERIAL_NS16550) += serial_ns16550.o Index: u-boot-v2.git/drivers/serial/serial_ns16550.c =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ u-boot-v2.git/drivers/serial/serial_ns16550.c 2008-05-20 18:04:13.000000000 -0500 @@ -0,0 +1,248 @@ +/** + * @file + * @brief NS16550 Driver implementation + * + * FileName: drivers/serial/serial_ns16550.c + * + * NS16550 support + * Modified from U-Boot V1 drivers/serial.c and drivers/ns16550.c + * originally from linux source (arch/ppc/boot/ns16550.c) + * modified to use CFG_ISA_MEM and new defines + */ +/* + * (C) Copyright 2008 + * Texas Instruments, <www.ti.com> + * Nishanth Menon x0nishan@ti.com + * + * (C) Copyright 2000 + * Rob Taylor, Flying Pig Systems. robt@flyingpig.com. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * 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., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + + +#include <common.h> +#include <driver.h> +#include <init.h> +#include <errno.h> +#include <malloc.h> +#include <asm/io.h> + +#include "serial_ns16550.h" +#include <ns16550.h> + +/* Forward declaration */ +static unsigned int ns16550_calc_divisor(struct console_device *cdev, + unsigned int baudrate); +static void ns16550_serial_init_port(struct console_device *cdev); +static void ns16550_putc(struct console_device *cdev, char c); +static int ns16550_getc(struct console_device *cdev); +static int ns16550_tstc(struct console_device *cdev); +static int ns16550_setbaudrate(struct console_device *cdev, int baud_rate); +static int ns16550_probe(struct device_d *dev); +static int ns16550_serial_init(void); + +/*********** Private Functions **********************************/ + +/** + * @brief ns16550_calc_divisor - compute the divisor for a baud rate + * + * @param[in] cdev - pointer to console device + * @param[in] baudrate - baud rate + * + * @return divisor to be set + */ +static unsigned int ns16550_calc_divisor(struct console_device *cdev, + unsigned int baudrate) +{ + unsigned int clk = ((struct NS16550_plat *) + (cdev->dev->platform_data))->clock; +#ifdef CONFIG_DRIVER_SERIAL_NS16550_OMAP_EXTENSIONS + /* FIXME: Legacy Code copied from U-Boot V1 implementation + */ +#ifdef CONFIG_ARCH_OMAP1510 + NS16550_t com_port = (NS16550_t) (cdev->dev->map_base); + /* If can't cleanly clock 115200 set div to 1 */ + if ((clk == 12000000) && (baudrate == 115200)) { + /* enable 6.5 * divisor */ + com_port->osc_12m_sel = OSC_12M_SEL; + return (1); /* return 1 for base divisor */ + } + com_port->osc_12m_sel = 0; /* clear if previsouly set */ +#elif defined(CONFIG_ARCH_OMAP1610) + /* If can't cleanly clock 115200 set div to 1 */ + if ((clk == 48000000) && (baudrate == 115200)) + return (26); /* return 26 for base divisor */ +#endif + +#endif /* End of OMAP specific handling */ + return (clk / MODE_X_DIV / baudrate); + +} + +/** + * @brief ns16550_serial_init_port - initialize the device + * + * @param cdev[in] - pointer to console device + */ +static void ns16550_serial_init_port(struct console_device *cdev) +{ + unsigned int baud_divisor; + NS16550_t com_port = (NS16550_t) (cdev->dev->map_base); + + /* Setup the serial port with the defaults first */ + baud_divisor = ns16550_calc_divisor(cdev, CONFIG_BAUDRATE); + + /* initializing the device for the first time */ + com_port->ier = 0x00; +#ifdef CONFIG_DRIVER_SERIAL_NS16550_OMAP_EXTENSIONS + com_port->mdr1 = 0x7; /* Disable */ +#endif + com_port->lcr = LCR_BKSE | LCRVAL; + com_port->dll = baud_divisor & 0xff; + com_port->dlm = (baud_divisor >> 8) & 0xff; + com_port->lcr = LCRVAL; + com_port->mcr = MCRVAL; + com_port->fcr = FCRVAL; +#ifdef CONFIG_DRIVER_SERIAL_NS16550_OMAP_EXTENSIONS + com_port->mdr1 = 0; /* enable uart mode */ +#endif +} + +/*********** Exposed Functions **********************************/ + +/** + * @brief ns16550_putc- put a character to the serial port + * + * @param cdev[in] - pointer to console device + * @param c[in] - character to put + */ +static void ns16550_putc(struct console_device *cdev, char c) +{ + NS16550_t com_port = (NS16550_t) (cdev->dev->map_base); + /* Loop Doing Nothing */ + while ((com_port->lsr & LSR_THRE) == 0) ; + com_port->thr = c; +} + +/** + * @brief ns16550_getc - retrieve a character from serial port + * + * @param cdev[in] - pointer to console device + * + * @return return the character read + */ +static int ns16550_getc(struct console_device *cdev) +{ + NS16550_t com_port = (NS16550_t) (cdev->dev->map_base); + /* Loop Doing Nothing */ + while ((com_port->lsr & LSR_DR) == 0) ; + return (com_port->rbr); +} + +/** + * @brief ns16550_tstc - test if character is available + * + * @param cdev[in] -pointer to console device + * + * @return - status based on data availability + */ +static int ns16550_tstc(struct console_device *cdev) +{ + NS16550_t com_port = (NS16550_t) (cdev->dev->map_base); + return ((com_port->lsr & LSR_DR) != 0); +} + +/** + * @brief ns16550_setbaudrate - set the baudrate for the uart port + * + * @param cdev[in] - console device + * @param baud_rate[in] - baud rate to set + * + * @return 0-implied to support the baudrate + */ +static int ns16550_setbaudrate(struct console_device *cdev, int baud_rate) +{ + NS16550_t com_port = (NS16550_t) (cdev->dev->map_base); + unsigned int baud_divisor = ns16550_calc_divisor(cdev, baud_rate); + com_port->ier = 0x00; + com_port->lcr = LCR_BKSE; + com_port->dll = baud_divisor & 0xff; + com_port->dlm = (baud_divisor >> 8) & 0xff; + com_port->lcr = LCRVAL; + com_port->mcr = MCRVAL; + com_port->fcr = FCRVAL; + return 0; +} + +/** + * @brief ns16550_probe - Probe entry point -called on the first + * match for device + * + * @param dev[in] - matched device + * + * @return EINVAL if platform_data is not populated, + * ENOMEM if calloc failed + * else return result of console_register + */ +static int ns16550_probe(struct device_d *dev) +{ + struct console_device *cdev; + struct NS16550_plat *plat = (struct NS16550_plat *)dev->platform_data; + + /* we do expect platform specific data */ + if (plat == NULL) + return -EINVAL; + cdev = calloc(1, sizeof(struct console_device)); + if (cdev == NULL) + return -ENOMEM; + + dev->type_data = cdev; + cdev->dev = dev; + cdev->f_caps = plat->f_caps; + cdev->tstc = ns16550_tstc; + cdev->putc = ns16550_putc; + cdev->getc = ns16550_getc; + cdev->setbrg = ns16550_setbaudrate; + + ns16550_serial_init_port(cdev); + + return console_register(cdev); +} + +/** + * @brief Driver registration structure + */ +static struct driver_d ns16550_serial_driver = { + .name = "serial_ns16550", + .probe = ns16550_probe, + .type = DEVICE_TYPE_CONSOLE, +}; + +/** + * @brief ns16550_serial_init - driver initialization function + * + * @return result of register_driver + */ +static int ns16550_serial_init(void) +{ + return register_driver(&ns16550_serial_driver); +} + +console_initcall(ns16550_serial_init); Index: u-boot-v2.git/drivers/serial/serial_ns16550.h =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ u-boot-v2.git/drivers/serial/serial_ns16550.h 2008-05-20 18:02:28.000000000 -0500 @@ -0,0 +1,183 @@ +/** + * @file + * @brief Serial NS16550 header + * + * FileName: drivers/serial/serial_ns16550.h + * + * @code struct NS16550 @endcode + * Register definitions for NS16550 device + */ +/* + * This file is licensed under + * the terms of the GNU General Public License version 2. This program + * is licensed "as is" without any warranty of any kind, whether express + * or implied. + * + * NS16550 Serial Port + * originally from linux source (arch/ppc/boot/ns16550.h) + * modified slightly to + * have addresses as offsets from CFG_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. + * + * added support for port on 64-bit bus + * by Richard Danter (richard.danter@windriver.com), (C) 2005 Wind River Systems + */ + + +#ifndef __SERIAL_NS16550__H +#define __SERIAL_NS16550__H +#ifdef CONFIG_DRIVER_SERIAL_NS16550_REG_SIZE_8_BITS +struct NS16550 { + /** RBR register */ + unsigned char rbr; /* 0 */ + unsigned char ier; /* 1 */ + unsigned char fcr; /* 2 */ + unsigned char lcr; /* 3 */ + unsigned char mcr; /* 4 */ + unsigned char lsr; /* 5 */ + unsigned char msr; /* 6 */ + unsigned char scr; /* 7 */ +#ifdef CONFIG_DRIVER_SERIAL_NS16550_OMAP_EXTENSIONS + unsigned char mdr1; /* 8 */ + unsigned char reg9; /* 9 */ + unsigned char regA; /* A */ + unsigned char regB; /* B */ + unsigned char regC; /* C */ + unsigned char regD; /* D */ + unsigned char regE; /* E */ + unsigned char regF; /* F */ + unsigned char reg10; /* 10 */ + unsigned char ssr; /* 11 */ +#endif +} __attribute__ ((packed)); +#elif defined(DRIVER_SERIAL_NS16550_REG_SIZE_16_BITS) +struct NS16550 { + unsigned short rbr; /* 0 */ + unsigned short ier; /* 1 */ + unsigned short fcr; /* 2 */ + unsigned short lcr; /* 3 */ + unsigned short mcr; /* 4 */ + unsigned short lsr; /* 5 */ + unsigned short msr; /* 6 */ + unsigned short scr; /* 7 */ +} __attribute__ ((packed)); +#elif defined(DRIVER_SERIAL_NS16550_REG_SIZE_32_BITS) +struct NS16550 { + unsigned long rbr; /* 0 r */ + unsigned long ier; /* 1 rw */ + unsigned long fcr; /* 2 w */ + unsigned long lcr; /* 3 rw */ + unsigned long mcr; /* 4 rw */ + unsigned long lsr; /* 5 r */ + unsigned long msr; /* 6 r */ + unsigned long scr; /* 7 rw */ +}; /* No need to pack an already aligned struct */ +#elif defined(CONFIG_DRIVER_SERIAL_NS16550_REG_SIZE_8_BITS_PAD_TO_32) +struct NS16550 { + unsigned char rbr; /* 0 */ + unsigned int pad1:24; + unsigned char ier; /* 1 */ + unsigned int pad2:24; + unsigned char fcr; /* 2 */ + unsigned int pad3:24; + unsigned char lcr; /* 3 */ + unsigned int pad4:24; + unsigned char mcr; /* 4 */ + unsigned int pad5:24; + unsigned char lsr; /* 5 */ + unsigned int pad6:24; + unsigned char msr; /* 6 */ + unsigned int pad7:24; + unsigned char scr; /* 7 */ + unsigned int pad8:24; +#ifdef CONFIG_DRIVER_SERIAL_NS16550_OMAP_EXTENSIONS + unsigned char mdr1; /* mode select reset TL16C750 */ +#ifdef CONFIG_ARCH_OMAP1510 + unsigned int pad9:24; + unsigned long pad[10]; + unsigned char osc_12m_sel; + unsigned int pad10:24; +#endif /* CONFIG_ARCH_OMAP1510 */ +#endif /* CONFIG_DRIVER_SERIAL_NS16550_OMAP_EXTENSIONS */ +} __attribute__ ((packed)); + +#elif defined(DRIVER_SERIAL_NS16550_REG_SIZE_8_BITS_PAD_TO_64) +struct NS16550 { + unsigned char rbr; /* 0 */ + unsigned char pad0[7]; + unsigned char ier; /* 1 */ + unsigned char pad1[7]; + unsigned char fcr; /* 2 */ + unsigned char pad2[7]; + unsigned char lcr; /* 3 */ + unsigned char pad3[7]; + unsigned char mcr; /* 4 */ + unsigned char pad4[7]; + unsigned char lsr; /* 5 */ + unsigned char pad5[7]; + unsigned char msr; /* 6 */ + unsigned char pad6[7]; + unsigned char scr; /* 7 */ + unsigned char pad7[7]; +} __attribute__ ((packed)); +#else +#error "Please define NS16550 registers size." +#endif + +#define thr rbr +#define iir fcr +#define dll rbr +#define dlm ier + +/** @brief typedef for register access */ +typedef volatile struct NS16550 *NS16550_t; + +#define FCR_FIFO_EN 0x01 /* Fifo enable */ +#define FCR_RXSR 0x02 /* Receiver soft reset */ +#define FCR_TXSR 0x04 /* Transmitter soft reset */ + +#define MCR_DTR 0x01 +#define MCR_RTS 0x02 +#define MCR_DMA_EN 0x04 +#define MCR_TX_DFR 0x08 + +#define LCR_WLS_MSK 0x03 /* character length select mask */ +#define LCR_WLS_5 0x00 /* 5 bit character length */ +#define LCR_WLS_6 0x01 /* 6 bit character length */ +#define LCR_WLS_7 0x02 /* 7 bit character length */ +#define LCR_WLS_8 0x03 /* 8 bit character length */ +/* Number of stop Bits, off = 1, on = 1.5 or 2) */ +#define LCR_STB 0x04 +#define LCR_PEN 0x08 /* Parity eneble */ +#define LCR_EPS 0x10 /* Even Parity Select */ +#define LCR_STKP 0x20 /* Stick Parity */ +#define LCR_SBRK 0x40 /* Set Break */ +#define LCR_BKSE 0x80 /* Bank select enable */ + +#define LSR_DR 0x01 /* Data ready */ +#define LSR_OE 0x02 /* Overrun */ +#define LSR_PE 0x04 /* Parity error */ +#define LSR_FE 0x08 /* Framing error */ +#define LSR_BI 0x10 /* Break */ +#define LSR_THRE 0x20 /* Xmit holding register empty */ +#define LSR_TEMT 0x40 /* Xmitter empty */ +#define LSR_ERR 0x80 /* Error */ + +#ifdef CONFIG_ARCH_OMAP1510 +#define OSC_12M_SEL 0x01 /* selects 6.5 * current clk div */ +#endif + +/* useful defaults for LCR */ +#define LCR_8N1 0x03 + +#define LCRVAL LCR_8N1 /* 8 data, 1 stop, no parity */ +#define MCRVAL (MCR_DTR | MCR_RTS) /* RTS/DTR */ +/* Clear & enable FIFOs */ +#define FCRVAL (FCR_FIFO_EN | FCR_RXSR | FCR_TXSR) + +#define MODE_X_DIV 16 + +#endif /* __SERIAL_NS16550__H */ Index: u-boot-v2.git/include/ns16550.h =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ u-boot-v2.git/include/ns16550.h 2008-05-20 18:02:28.000000000 -0500 @@ -0,0 +1,46 @@ +/** + * @file + * @brief Serial NS16550 platform specific header + * + * FileName: include/ns16550.h + * @code struct NS16550_plat @endcode + * represents The specifics of the device present in the system. + */ +/* + * (C) Copyright 2008 + * Texas Instruments, <www.ti.com> + * Nishanth Menon x0nishan@ti.com + * + * 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., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#ifndef __NS16650_PLATFORM_H_ +#define __NS16650_PLATFORM_H_ + +/** + * @brief Platform dependent feature: + * Pass pointer to this structure as part of device_d -> platform_data + */ +struct NS16550_plat { + /** Clock speed */ + unsigned int clock; + /** Console capabilities: + * CONSOLE_STDIN | CONSOLE_STDOUT | CONSOLE_STDERR @see console.h + */ + unsigned char f_caps; +}; + +#endif /* __NS16650_PLATFORM_H_ */