[U-Boot-Users] [Patch 09/17] U-Boot-V2:Serial: Add support for NS16550 Driver.`
Menon, Nishanth
x0nishan at ti.com
Wed May 21 18:28:29 CEST 2008
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 Menon<x0nishan at 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 at ti.com>
+ *
+ * (C) Copyright 2000
+ * Rob Taylor, Flying Pig Systems. robt at 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 at 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 at 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_ */
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