/* This file contains the driver for the GRLIB APBUART serial port. The driver
* is implemented by using the cons.c console layer. Interrupt/Polling/Task
* driven mode can be configured using driver resources:
*
* - mode (0=Polling, 1=Interrupt, 2=Task-Driven-Interrupt Mode)
* - syscon (0=Force not Ssystem Console, 1=Suggest System Console)
*
* The BSP define APBUART_INFO_AVAIL in order to add the info routine
* used for debugging.
*
* COPYRIGHT (c) 2010.
* Cobham Gaisler AB.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*/
/******************* Driver manager interface ***********************/
#include <bsp.h>
#include <rtems/libio.h>
#include <stdlib.h>
#include <assert.h>
#include <rtems/bspIo.h>
#include <string.h>
#include <stdio.h>
#include <drvmgr/drvmgr.h>
#include <drvmgr/ambapp_bus.h>
#include <bsp/apbuart.h>
#include <ambapp.h>
#include <grlib.h>
#include <bsp/cons.h>
#include <rtems/termiostypes.h>
#include <bsp/apbuart_cons.h>
/*#define DEBUG 1 */
#ifdef DEBUG
#define DBG(x...) printk(x)
#else
#define DBG(x...)
#endif
/* LEON3 Low level transmit/receive functions provided by debug-uart code */
extern void apbuart_outbyte_polled(
struct apbuart_regs *regs,
unsigned char ch,
int do_cr_on_newline,
int wait_sent);
extern int apbuart_inbyte_nonblocking(struct apbuart_regs *regs);
extern struct apbuart_regs *dbg_uart; /* The debug UART */
struct apbuart_priv {
struct console_dev condev;
struct drvmgr_dev *dev;
struct apbuart_regs *regs;
char devName[32];
void *cookie;
int sending;
int mode;
};
/* TERMIOS Layer Callback functions */
void apbuart_get_attributes(struct console_dev *condev, struct termios *t);
int apbuart_set_attributes(int minor, const struct termios *t);
ssize_t apbuart_write_polled(int minor, const char *buf, size_t len);
int apbuart_pollRead(int minor);
ssize_t apbuart_write_intr(int minor, const char *buf, size_t len);
int apbuart_pollRead_task(int minor);
int apbuart_firstOpen(int major, int minor, void *arg);
int apbuart_lastClose(int major, int minor, void *arg);
void apbuart_isr(void *arg);
int apbuart_get_baud(struct apbuart_priv *uart);
int apbuart_init1(struct drvmgr_dev *dev);
#ifdef APBUART_INFO_AVAIL
static int apbuart_info(
struct drvmgr_dev *dev,
void (*print_line)(void *p, char *str),
void *p, int, char *argv[]);
#define APBUART_INFO_FUNC apbuart_info
#else
#define APBUART_INFO_FUNC NULL
#endif
struct drvmgr_drv_ops apbuart_ops =
{
.init = {apbuart_init1, NULL, NULL, NULL},
.remove = NULL,
.info = APBUART_INFO_FUNC
};
static struct amba_dev_id apbuart_ids[] =
{
{VENDOR_GAISLER, GAISLER_APBUART},
{0, 0} /* Mark end of table */
};
static struct amba_drv_info apbuart_drv_info =
{
{
DRVMGR_OBJ_DRV, /* Driver */
NULL, /* Next driver */
NULL, /* Device list */
DRIVER_AMBAPP_GAISLER_APBUART_ID, /* Driver ID */
"APBUART_DRV", /* Driver Name */
DRVMGR_BUS_TYPE_AMBAPP, /* Bus Type */
&apbuart_ops,
NULL, /* Funcs */
0, /* No devices yet */
sizeof(struct apbuart_priv), /*DrvMgr alloc private*/
},
&apbuart_ids[0]
};
void apbuart_cons_register_drv (void)
{
DBG("Registering APBUART Console driver\n");
drvmgr_drv_register(&apbuart_drv_info.general);
}
/* Interrupt mode routines */
static const rtems_termios_callbacks Callbacks_intr = {
apbuart_firstOpen, /* firstOpen */
apbuart_lastClose, /* lastClose */
NULL, /* pollRead */
apbuart_write_intr, /* write */
apbuart_set_attributes, /* setAttributes */
NULL, /* stopRemoteTx */
NULL, /* startRemoteTx */
TERMIOS_IRQ_DRIVEN /* outputUsesInterrupts */
};
/* Polling mode routines */
static const rtems_termios_callbacks Callbacks_task = {
apbuart_firstOpen, /* firstOpen */
apbuart_lastClose, /* lastClose */
apbuart_pollRead_task, /* pollRead */
apbuart_write_intr, /* write */
apbuart_set_attributes, /* setAttributes */
NULL, /* stopRemoteTx */
NULL, /* startRemoteTx */
TERMIOS_TASK_DRIVEN /* outputUsesInterrupts */
};
/* Polling mode routines */
static const rtems_termios_callbacks Callbacks_poll = {
apbuart_firstOpen, /* firstOpen */
apbuart_lastClose, /* lastClose */
apbuart_pollRead, /* pollRead */
apbuart_write_polled, /* write */
apbuart_set_attributes, /* setAttributes */
NULL, /* stopRemoteTx */
NULL, /* startRemoteTx */
TERMIOS_POLLED /* outputUsesInterrupts */
};
int apbuart_init1(struct drvmgr_dev *dev)
{
struct apbuart_priv *priv;
struct amba_dev_info *ambadev;
struct ambapp_core *pnpinfo;
union drvmgr_key_value *value;
char prefix[32];
unsigned int db;
static int first_uart = 1;
/* The default operation in AMP is to use APBUART[0] for CPU[0],
* APBUART[1] for CPU[1] and so on. The remaining UARTs is not used
* since we don't know how many CPU-cores there are. Note this only
* affects the on-chip amba bus (the root bus). The user can override
* the default resource sharing by defining driver resources for the
* APBUART devices on each AMP OS instance.
*/
#if defined(RTEMS_MULTIPROCESSING) && defined(LEON3)
if (drvmgr_on_rootbus(dev) && dev->minor_drv != LEON3_Cpu_Index &&
drvmgr_keys_get(dev, NULL) != 0) {
/* User hasn't configured on-chip APBUART, leave it untouched */
return DRVMGR_EBUSY;
}
#endif
DBG("APBUART[%d] on bus %s\n", dev->minor_drv, dev->parent->dev->name);
/* Private data was allocated and zeroed by driver manager */
priv = dev->priv;
if (!priv)
return DRVMGR_NOMEM;
priv->dev = dev;
/* Get device information from AMBA PnP information */
ambadev = (struct amba_dev_info *)priv->dev->businfo;
if (ambadev == NULL)
return -1;
pnpinfo = &ambadev->info;
priv->regs = (struct apbuart_regs *)pnpinfo->apb_slv->start;
/* Clear HW regs, leave baudrate register as it is */
priv->regs->status = 0;
/* leave Transmitter/receiver if this is the RTEMS debug UART (assume
* it has been setup by boot loader).
*/
db = 0;
#ifdef LEON3
if (priv->regs == dbg_uart) {
db = priv->regs->ctrl & (LEON_REG_UART_CTRL_RE |
LEON_REG_UART_CTRL_TE |
LEON_REG_UART_CTRL_PE |
LEON_REG_UART_CTRL_PS);
}
#endif
/* Let UART debug tunnelling be untouched if Flow-control is set.
*
* With old APBUARTs debug is enabled by setting LB and FL, since LB or
* DB are not reset we can not trust them. However since FL is reset we
* guess that we are debugging if FL is already set, the debugger set
* either LB or DB depending on UART capabilities.
*/
if (priv->regs->ctrl & LEON_REG_UART_CTRL_FL) {
db |= priv->regs->ctrl & (LEON_REG_UART_CTRL_DB |
LEON_REG_UART_CTRL_LB | LEON_REG_UART_CTRL_FL);
}
priv->regs->ctrl = db;
/* The system console and Debug console may depend on this device, so
* initialize it straight away.
*
* We default to have System Console on first APBUART, user may override
* this behaviour by setting the syscon option to 0.
*/
if (drvmgr_on_rootbus(dev) && first_uart) {
priv->condev.flags = CONSOLE_FLAG_SYSCON;
first_uart = 0;
} else {
priv->condev.flags = 0;
}
value = drvmgr_dev_key_get(priv->dev, "syscon", KEY_TYPE_INT);
if (value) {
if (value->i)
priv->condev.flags |= CONSOLE_FLAG_SYSCON;
else
priv->condev.flags &= ~CONSOLE_FLAG_SYSCON;
}
priv->condev.fsname = NULL;
priv->condev.ops.get_uart_attrs = apbuart_get_attributes;
/* Select 0=Polled, 1=IRQ, 2=Task-Driven UART Mode */
value = drvmgr_dev_key_get(priv->dev, "mode", KEY_TYPE_INT);
if (value)
priv->mode = value->i;
else
priv->mode = TERMIOS_POLLED;
if (priv->mode == TERMIOS_IRQ_DRIVEN) {
priv->condev.callbacks = &Callbacks_intr;
} else if (priv->mode == TERMIOS_TASK_DRIVEN) {
priv->condev.callbacks = &Callbacks_task;
} else {
priv->condev.callbacks = &Callbacks_poll;
}
/* Get Filesystem name prefix */
prefix[0] = '\0';
if (drvmgr_get_dev_prefix(dev, prefix)) {
/* Got special prefix, this means we have a bus prefix
* And we should use our "bus minor"
*/
sprintf(priv->devName, "/dev/%sapbuart%d", prefix, dev->minor_bus);
priv->condev.fsname = priv->devName;
}
/* Register it as a console device, the console driver will register
* a termios device as well
*/
console_dev_register(&priv->condev);
return DRVMGR_OK;
}
#ifdef APBUART_INFO_AVAIL
static int apbuart_info(
struct drvmgr_dev *dev,
void (*print_line)(void *p, char *str),
void *p, int argc, char *argv[])
{
struct apbuart_priv *priv = dev->priv;
char *str1;
char buf[64];
if (dev->priv == NULL)
return -DRVMGR_EINVAL;
if (priv->mode == TERMIOS_POLLED)
str1 = "TERMIOS_POLLED";
else if (priv->mode == TERMIOS_TASK_DRIVEN)
str1 = "TERMIOS_TASK_DRIVEN";
else if (priv->mode == TERMIOS_TASK_DRIVEN)
str1 = "TERMIOS_TASK_DRIVEN";
else
str1 = "BAD MODE";
sprintf(buf, "UART Mode: %s", str1);
print_line(p, buf);
if (priv->condev.fsname) {
sprintf(buf, "FS Name: %s", priv->condev.fsname);
print_line(p, buf);
}
sprintf(buf, "STATUS REG: 0x%x", priv->regs->status);
print_line(p, buf);
sprintf(buf, "CTRL REG: 0x%x", priv->regs->ctrl);
print_line(p, buf);
sprintf(buf, "SCALER REG: 0x%x baud rate %d",
priv->regs->scaler, apbuart_get_baud(priv));
print_line(p, buf);
return DRVMGR_OK;
}
#endif
#ifndef LEON3
/* This routine transmits a character, it will busy-wait until on character
* fits in the APBUART Transmit FIFO
*/
void apbuart_outbyte_polled(
struct apbuart_regs *regs,
unsigned char ch,
int do_cr_on_newline,
int wait_sent)
{
send:
while ((regs->status & LEON_REG_UART_STATUS_THE) == 0) {
/* Lower bus utilization while waiting for UART */
asm volatile ("nop"::); asm volatile ("nop"::);
asm volatile ("nop"::); asm volatile ("nop"::);
asm volatile ("nop"::); asm volatile ("nop"::);
asm volatile ("nop"::); asm volatile ("nop"::);
}
regs->data = (unsigned int) ch;
if ((ch == '\n') && do_cr_on_newline) {
ch = '\r';
goto send;
}
/* Wait until the character has been sent? */
if (wait_sent) {
while ((regs->status & LEON_REG_UART_STATUS_THE) == 0)
;
}
}
/* This routine polls for one character, return EOF if no character is available */
int apbuart_inbyte_nonblocking(struct apbuart_regs *regs)
{
if (regs->status & LEON_REG_UART_STATUS_ERR) {
regs->status = ~LEON_REG_UART_STATUS_ERR;
}
if ((regs->status & LEON_REG_UART_STATUS_DR) == 0)
return EOF;
return (int)regs->data;
}
#endif
int apbuart_firstOpen(int major, int minor, void *arg)
{
struct apbuart_priv *uart = (struct apbuart_priv *)minor;
rtems_libio_open_close_args_t *ioarg = arg;
if ( ioarg && ioarg->iop )
uart->cookie = ioarg->iop->data1;
else
uart->cookie = NULL;
/* Enable TX/RX */
uart->regs->ctrl |= LEON_REG_UART_CTRL_RE | LEON_REG_UART_CTRL_TE;
if (uart->mode != TERMIOS_POLLED) {
/* Register interrupt and enable it */
drvmgr_interrupt_register(uart->dev, 0, "apbuart",
apbuart_isr, uart);
uart->sending = 0;
/* Turn on RX interrupts */
uart->regs->ctrl |= LEON_REG_UART_CTRL_RI;
}
return 0;
}
int apbuart_lastClose(int major, int minor, void *arg)
{
struct apbuart_priv *uart = (struct apbuart_priv *)minor;
if (uart->mode != TERMIOS_POLLED) {
/* Turn off RX interrupts */
uart->regs->ctrl &= ~(LEON_REG_UART_CTRL_RI);
/**** Flush device ****/
while (uart->sending) {
/* Wait until all data has been sent */
}
/* Disable and unregister interrupt handler */
drvmgr_interrupt_unregister(uart->dev, 0, apbuart_isr, uart);
}
#ifdef LEON3
/* Disable TX/RX if not used for DEBUG */
if (uart->regs != dbg_uart)
uart->regs->ctrl &= ~(LEON_REG_UART_CTRL_RE | LEON_REG_UART_CTRL_TE);
#endif
return 0;
}
int apbuart_pollRead(int minor)
{
struct apbuart_priv *uart = (struct apbuart_priv *)minor;
return apbuart_inbyte_nonblocking(uart->regs);
}
int apbuart_pollRead_task(int minor)
{
struct apbuart_priv *uart = (struct apbuart_priv *)minor;
int c, tot;
char buf[32];
tot = 0;
while ((c=apbuart_inbyte_nonblocking(uart->regs)) != EOF) {
buf[tot] = c;
tot++;
if (tot > 31) {
rtems_termios_enqueue_raw_characters(uart->cookie, buf, tot);
tot = 0;
}
}
if (tot > 0)
rtems_termios_enqueue_raw_characters(uart->cookie, buf, tot);
return EOF;
}
struct apbuart_baud {
unsigned int num;
unsigned int baud;
};
static struct apbuart_baud apbuart_baud_table[] = {
{B50, 50},
{B75, 75},
{B110, 110},
{B134, 134},
{B150, 150},
{B200, 200},
{B300, 300},
{B600, 600},
{B1200, 1200},
{B1800, 1800},
{B2400, 2400},
{B4800, 4800},
{B9600, 9600},
{B19200, 19200},
{B38400, 38400},
{B57600, 57600},
{B115200, 115200},
{B230400, 230400},
{B460800, 460800},
};
#define BAUD_NUM (sizeof(apbuart_baud_table)/sizeof(struct apbuart_baud))
static int apbuart_baud_num2baud(unsigned int num)
{
int i;
for(i=0; i<BAUD_NUM; i++)
if (apbuart_baud_table[i].num == num)
return apbuart_baud_table[i].baud;
return -1;
}
static struct apbuart_baud *apbuart_baud_find_closest(unsigned int baud)
{
int i, diff;
for(i=0; i<BAUD_NUM-1; i++) {
diff = apbuart_baud_table[i+1].baud -
apbuart_baud_table[i].baud;
if (baud < (apbuart_baud_table[i].baud + diff/2))
return &apbuart_baud_table[i];
}
return &apbuart_baud_table[BAUD_NUM-1];
}
int apbuart_get_baud(struct apbuart_priv *uart)
{
unsigned int core_clk_hz;
unsigned int scaler;
/* Get current scaler setting */
scaler = uart->regs->scaler;
/* Get APBUART core frequency */
drvmgr_freq_get(uart->dev, DEV_APB_SLV, &core_clk_hz);
/* Calculate baud rate from generator "scaler" number */
return core_clk_hz / ((scaler + 1) * 8);
}
static struct apbuart_baud *apbuart_get_baud_closest(struct apbuart_priv *uart)
{
return apbuart_baud_find_closest(apbuart_get_baud(uart));
}
int apbuart_set_attributes(int minor, const struct termios *t)
{
unsigned int core_clk_hz;
unsigned int scaler;
unsigned int ctrl;
int baud;
struct apbuart_priv *uart = (struct apbuart_priv *)minor;
switch(t->c_cflag & CSIZE) {
default:
case CS5:
case CS6:
case CS7:
/* Hardware doesn't support other than CS8 */
return -1;
case CS8:
break;
}
/* Read out current value */
ctrl = uart->regs->ctrl;
switch(t->c_cflag & (PARENB|PARODD)){
case (PARENB|PARODD):
/* Odd parity */
ctrl |= LEON_REG_UART_CTRL_PE|LEON_REG_UART_CTRL_PS;
break;
case PARENB:
/* Even parity */
ctrl &= ~LEON_REG_UART_CTRL_PS;
ctrl |= LEON_REG_UART_CTRL_PE;
break;
default:
case 0:
case PARODD:
/* No Parity */
ctrl &= ~(LEON_REG_UART_CTRL_PS|LEON_REG_UART_CTRL_PE);
}
if (!(t->c_cflag & CLOCAL))
ctrl |= LEON_REG_UART_CTRL_FL;
else
ctrl &= ~LEON_REG_UART_CTRL_FL;
/* Update new settings */
uart->regs->ctrl = ctrl;
/* Baud rate */
baud = apbuart_baud_num2baud(t->c_cflag & CBAUD);
if (baud > 0){
/* Get APBUART core frequency */
drvmgr_freq_get(uart->dev, DEV_APB_SLV, &core_clk_hz);
/* Calculate Baud rate generator "scaler" number */
scaler = (((core_clk_hz*10)/(baud*8))-5)/10;
/* Set new baud rate by setting scaler */
uart->regs->scaler = scaler;
}
return 0;
}
void apbuart_get_attributes(struct console_dev *condev, struct termios *t)
{
struct apbuart_priv *uart = (struct apbuart_priv *)condev;
unsigned int ctrl;
struct apbuart_baud *baud;
t->c_cflag = t->c_cflag & ~(CSIZE|PARENB|PARODD|CLOCAL|CBAUD);
/* Hardware support only CS8 */
t->c_cflag |= CS8;
/* Read out current parity */
ctrl = uart->regs->ctrl;
if (ctrl & LEON_REG_UART_CTRL_PE) {
if (ctrl & LEON_REG_UART_CTRL_PS)
t->c_cflag |= PARENB|PARODD; /* Odd parity */
else
t->c_cflag |= PARENB; /* Even parity */
}
if ((ctrl & LEON_REG_UART_CTRL_FL) == 0)
t->c_cflag |= CLOCAL;
baud = apbuart_get_baud_closest(uart);
t->c_cflag |= baud->num;
}
ssize_t apbuart_write_polled(int minor, const char *buf, size_t len)
{
int nwrite = 0;
struct apbuart_priv *uart = (struct apbuart_priv *)minor;
while (nwrite < len) {
apbuart_outbyte_polled(uart->regs, *buf++, 0, 0);
nwrite++;
}
return nwrite;
}
ssize_t apbuart_write_intr(int minor, const char *buf, size_t len)
{
struct apbuart_priv *uart = (struct apbuart_priv *)minor;
unsigned int oldLevel;
unsigned int ctrl;
rtems_interrupt_disable(oldLevel);
/* Enable TX interrupt */
ctrl = uart->regs->ctrl;
uart->regs->ctrl = ctrl | LEON_REG_UART_CTRL_TI;
if (ctrl & LEON_REG_UART_CTRL_FA) {
/* APBUART with FIFO.. Fill as many as FIFO allows */
uart->sending = 0;
while (((uart->regs->status & LEON_REG_UART_STATUS_TF) == 0) &&
(uart->sending < len)) {
uart->regs->data = *buf;
buf++;
uart->sending++;
}
} else {
/* start UART TX, this will result in an interrupt when done */
uart->regs->data = *buf;
uart->sending = 1;
}
rtems_interrupt_enable(oldLevel);
return 0;
}
/* Handle UART interrupts */
void apbuart_isr(void *arg)
{
struct apbuart_priv *uart = arg;
unsigned int status;
char data;
int cnt;
/* Get all received characters */
if (uart->mode == TERMIOS_TASK_DRIVEN) {
if ((status=uart->regs->status) & LEON_REG_UART_STATUS_DR)
rtems_termios_rxirq_occured(uart->cookie);
} else {
while ((status=uart->regs->status) & LEON_REG_UART_STATUS_DR) {
/* Data has arrived, get new data */
data = uart->regs->data;
/* Tell termios layer about new character */
rtems_termios_enqueue_raw_characters(uart->cookie, &data, 1);
}
}
if (uart->sending && (status & LEON_REG_UART_STATUS_THE)) {
/* Sent the one char, we disable TX interrupts */
uart->regs->ctrl &= ~LEON_REG_UART_CTRL_TI;
/* Tell close that we sent everything */
cnt = uart->sending;
uart->sending = 0;
/* apbuart_write_intr() will get called from this function */
rtems_termios_dequeue_characters(uart->cookie, cnt);
}
}
