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remarkable-linux/drivers/serial/sunsu.c
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers 
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00

1585 lines
37 KiB
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/* $Id: su.c,v 1.55 2002/01/08 16:00:16 davem Exp $
* su.c: Small serial driver for keyboard/mouse interface on sparc32/PCI
*
* Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
* Copyright (C) 1998-1999 Pete Zaitcev (zaitcev@yahoo.com)
*
* This is mainly a variation of 8250.c, credits go to authors mentioned
* therein. In fact this driver should be merged into the generic 8250.c
* infrastructure perhaps using a 8250_sparc.c module.
*
* Fixed to use tty_get_baud_rate().
* Theodore Ts'o <tytso@mit.edu>, 2001-Oct-12
*
* Converted to new 2.5.x UART layer.
* David S. Miller (davem@davemloft.net), 2002-Jul-29
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/circ_buf.h>
#include <linux/serial.h>
#include <linux/sysrq.h>
#include <linux/console.h>
#ifdef CONFIG_SERIO
#include <linux/serio.h>
#endif
#include <linux/serial_reg.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/prom.h>
#include <asm/of_device.h>
#if defined(CONFIG_SERIAL_SUNSU_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/serial_core.h>
#include "suncore.h"
/* We are on a NS PC87303 clocked with 24.0 MHz, which results
* in a UART clock of 1.8462 MHz.
*/
#define SU_BASE_BAUD (1846200 / 16)
enum su_type { SU_PORT_NONE, SU_PORT_MS, SU_PORT_KBD, SU_PORT_PORT };
static char *su_typev[] = { "su(???)", "su(mouse)", "su(kbd)", "su(serial)" };
/*
* Here we define the default xmit fifo size used for each type of UART.
*/
static const struct serial_uart_config uart_config[PORT_MAX_8250+1] = {
{ "unknown", 1, 0 },
{ "8250", 1, 0 },
{ "16450", 1, 0 },
{ "16550", 1, 0 },
{ "16550A", 16, UART_CLEAR_FIFO | UART_USE_FIFO },
{ "Cirrus", 1, 0 },
{ "ST16650", 1, UART_CLEAR_FIFO | UART_STARTECH },
{ "ST16650V2", 32, UART_CLEAR_FIFO | UART_USE_FIFO | UART_STARTECH },
{ "TI16750", 64, UART_CLEAR_FIFO | UART_USE_FIFO },
{ "Startech", 1, 0 },
{ "16C950/954", 128, UART_CLEAR_FIFO | UART_USE_FIFO },
{ "ST16654", 64, UART_CLEAR_FIFO | UART_USE_FIFO | UART_STARTECH },
{ "XR16850", 128, UART_CLEAR_FIFO | UART_USE_FIFO | UART_STARTECH },
{ "RSA", 2048, UART_CLEAR_FIFO | UART_USE_FIFO }
};
struct uart_sunsu_port {
struct uart_port port;
unsigned char acr;
unsigned char ier;
unsigned short rev;
unsigned char lcr;
unsigned int lsr_break_flag;
unsigned int cflag;
/* Probing information. */
enum su_type su_type;
unsigned int type_probed; /* XXX Stupid */
unsigned long reg_size;
#ifdef CONFIG_SERIO
struct serio serio;
int serio_open;
#endif
};
static unsigned int serial_in(struct uart_sunsu_port *up, int offset)
{
offset <<= up->port.regshift;
switch (up->port.iotype) {
case UPIO_HUB6:
outb(up->port.hub6 - 1 + offset, up->port.iobase);
return inb(up->port.iobase + 1);
case UPIO_MEM:
return readb(up->port.membase + offset);
default:
return inb(up->port.iobase + offset);
}
}
static void serial_out(struct uart_sunsu_port *up, int offset, int value)
{
#ifndef CONFIG_SPARC64
/*
* MrCoffee has weird schematics: IRQ4 & P10(?) pins of SuperIO are
* connected with a gate then go to SlavIO. When IRQ4 goes tristated
* gate outputs a logical one. Since we use level triggered interrupts
* we have lockup and watchdog reset. We cannot mask IRQ because
* keyboard shares IRQ with us (Word has it as Bob Smelik's design).
* This problem is similar to what Alpha people suffer, see serial.c.
*/
if (offset == UART_MCR)
value |= UART_MCR_OUT2;
#endif
offset <<= up->port.regshift;
switch (up->port.iotype) {
case UPIO_HUB6:
outb(up->port.hub6 - 1 + offset, up->port.iobase);
outb(value, up->port.iobase + 1);
break;
case UPIO_MEM:
writeb(value, up->port.membase + offset);
break;
default:
outb(value, up->port.iobase + offset);
}
}
/*
* We used to support using pause I/O for certain machines. We
* haven't supported this for a while, but just in case it's badly
* needed for certain old 386 machines, I've left these #define's
* in....
*/
#define serial_inp(up, offset) serial_in(up, offset)
#define serial_outp(up, offset, value) serial_out(up, offset, value)
/*
* For the 16C950
*/
static void serial_icr_write(struct uart_sunsu_port *up, int offset, int value)
{
serial_out(up, UART_SCR, offset);
serial_out(up, UART_ICR, value);
}
#if 0 /* Unused currently */
static unsigned int serial_icr_read(struct uart_sunsu_port *up, int offset)
{
unsigned int value;
serial_icr_write(up, UART_ACR, up->acr | UART_ACR_ICRRD);
serial_out(up, UART_SCR, offset);
value = serial_in(up, UART_ICR);
serial_icr_write(up, UART_ACR, up->acr);
return value;
}
#endif
#ifdef CONFIG_SERIAL_8250_RSA
/*
* Attempts to turn on the RSA FIFO. Returns zero on failure.
* We set the port uart clock rate if we succeed.
*/
static int __enable_rsa(struct uart_sunsu_port *up)
{
unsigned char mode;
int result;
mode = serial_inp(up, UART_RSA_MSR);
result = mode & UART_RSA_MSR_FIFO;
if (!result) {
serial_outp(up, UART_RSA_MSR, mode | UART_RSA_MSR_FIFO);
mode = serial_inp(up, UART_RSA_MSR);
result = mode & UART_RSA_MSR_FIFO;
}
if (result)
up->port.uartclk = SERIAL_RSA_BAUD_BASE * 16;
return result;
}
static void enable_rsa(struct uart_sunsu_port *up)
{
if (up->port.type == PORT_RSA) {
if (up->port.uartclk != SERIAL_RSA_BAUD_BASE * 16) {
spin_lock_irq(&up->port.lock);
__enable_rsa(up);
spin_unlock_irq(&up->port.lock);
}
if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16)
serial_outp(up, UART_RSA_FRR, 0);
}
}
/*
* Attempts to turn off the RSA FIFO. Returns zero on failure.
* It is unknown why interrupts were disabled in here. However,
* the caller is expected to preserve this behaviour by grabbing
* the spinlock before calling this function.
*/
static void disable_rsa(struct uart_sunsu_port *up)
{
unsigned char mode;
int result;
if (up->port.type == PORT_RSA &&
up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) {
spin_lock_irq(&up->port.lock);
mode = serial_inp(up, UART_RSA_MSR);
result = !(mode & UART_RSA_MSR_FIFO);
if (!result) {
serial_outp(up, UART_RSA_MSR, mode & ~UART_RSA_MSR_FIFO);
mode = serial_inp(up, UART_RSA_MSR);
result = !(mode & UART_RSA_MSR_FIFO);
}
if (result)
up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16;
spin_unlock_irq(&up->port.lock);
}
}
#endif /* CONFIG_SERIAL_8250_RSA */
static inline void __stop_tx(struct uart_sunsu_port *p)
{
if (p->ier & UART_IER_THRI) {
p->ier &= ~UART_IER_THRI;
serial_out(p, UART_IER, p->ier);
}
}
static void sunsu_stop_tx(struct uart_port *port)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
__stop_tx(up);
/*
* We really want to stop the transmitter from sending.
*/
if (up->port.type == PORT_16C950) {
up->acr |= UART_ACR_TXDIS;
serial_icr_write(up, UART_ACR, up->acr);
}
}
static void sunsu_start_tx(struct uart_port *port)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
if (!(up->ier & UART_IER_THRI)) {
up->ier |= UART_IER_THRI;
serial_out(up, UART_IER, up->ier);
}
/*
* Re-enable the transmitter if we disabled it.
*/
if (up->port.type == PORT_16C950 && up->acr & UART_ACR_TXDIS) {
up->acr &= ~UART_ACR_TXDIS;
serial_icr_write(up, UART_ACR, up->acr);
}
}
static void sunsu_stop_rx(struct uart_port *port)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
up->ier &= ~UART_IER_RLSI;
up->port.read_status_mask &= ~UART_LSR_DR;
serial_out(up, UART_IER, up->ier);
}
static void sunsu_enable_ms(struct uart_port *port)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
unsigned long flags;
spin_lock_irqsave(&up->port.lock, flags);
up->ier |= UART_IER_MSI;
serial_out(up, UART_IER, up->ier);
spin_unlock_irqrestore(&up->port.lock, flags);
}
static struct tty_struct *
receive_chars(struct uart_sunsu_port *up, unsigned char *status)
{
struct tty_struct *tty = up->port.info->tty;
unsigned char ch, flag;
int max_count = 256;
int saw_console_brk = 0;
do {
ch = serial_inp(up, UART_RX);
flag = TTY_NORMAL;
up->port.icount.rx++;
if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
UART_LSR_FE | UART_LSR_OE))) {
/*
* For statistics only
*/
if (*status & UART_LSR_BI) {
*status &= ~(UART_LSR_FE | UART_LSR_PE);
up->port.icount.brk++;
if (up->port.cons != NULL &&
up->port.line == up->port.cons->index)
saw_console_brk = 1;
/*
* We do the SysRQ and SAK checking
* here because otherwise the break
* may get masked by ignore_status_mask
* or read_status_mask.
*/
if (uart_handle_break(&up->port))
goto ignore_char;
} else if (*status & UART_LSR_PE)
up->port.icount.parity++;
else if (*status & UART_LSR_FE)
up->port.icount.frame++;
if (*status & UART_LSR_OE)
up->port.icount.overrun++;
/*
* Mask off conditions which should be ingored.
*/
*status &= up->port.read_status_mask;
if (up->port.cons != NULL &&
up->port.line == up->port.cons->index) {
/* Recover the break flag from console xmit */
*status |= up->lsr_break_flag;
up->lsr_break_flag = 0;
}
if (*status & UART_LSR_BI) {
flag = TTY_BREAK;
} else if (*status & UART_LSR_PE)
flag = TTY_PARITY;
else if (*status & UART_LSR_FE)
flag = TTY_FRAME;
}
if (uart_handle_sysrq_char(&up->port, ch))
goto ignore_char;
if ((*status & up->port.ignore_status_mask) == 0)
tty_insert_flip_char(tty, ch, flag);
if (*status & UART_LSR_OE)
/*
* Overrun is special, since it's reported
* immediately, and doesn't affect the current
* character.
*/
tty_insert_flip_char(tty, 0, TTY_OVERRUN);
ignore_char:
*status = serial_inp(up, UART_LSR);
} while ((*status & UART_LSR_DR) && (max_count-- > 0));
if (saw_console_brk)
sun_do_break();
return tty;
}
static void transmit_chars(struct uart_sunsu_port *up)
{
struct circ_buf *xmit = &up->port.info->xmit;
int count;
if (up->port.x_char) {
serial_outp(up, UART_TX, up->port.x_char);
up->port.icount.tx++;
up->port.x_char = 0;
return;
}
if (uart_tx_stopped(&up->port)) {
sunsu_stop_tx(&up->port);
return;
}
if (uart_circ_empty(xmit)) {
__stop_tx(up);
return;
}
count = up->port.fifosize;
do {
serial_out(up, UART_TX, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
up->port.icount.tx++;
if (uart_circ_empty(xmit))
break;
} while (--count > 0);
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&up->port);
if (uart_circ_empty(xmit))
__stop_tx(up);
}
static void check_modem_status(struct uart_sunsu_port *up)
{
int status;
status = serial_in(up, UART_MSR);
if ((status & UART_MSR_ANY_DELTA) == 0)
return;
if (status & UART_MSR_TERI)
up->port.icount.rng++;
if (status & UART_MSR_DDSR)
up->port.icount.dsr++;
if (status & UART_MSR_DDCD)
uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
if (status & UART_MSR_DCTS)
uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
wake_up_interruptible(&up->port.info->delta_msr_wait);
}
static irqreturn_t sunsu_serial_interrupt(int irq, void *dev_id)
{
struct uart_sunsu_port *up = dev_id;
unsigned long flags;
unsigned char status;
spin_lock_irqsave(&up->port.lock, flags);
do {
struct tty_struct *tty;
status = serial_inp(up, UART_LSR);
tty = NULL;
if (status & UART_LSR_DR)
tty = receive_chars(up, &status);
check_modem_status(up);
if (status & UART_LSR_THRE)
transmit_chars(up);
spin_unlock_irqrestore(&up->port.lock, flags);
if (tty)
tty_flip_buffer_push(tty);
spin_lock_irqsave(&up->port.lock, flags);
} while (!(serial_in(up, UART_IIR) & UART_IIR_NO_INT));
spin_unlock_irqrestore(&up->port.lock, flags);
return IRQ_HANDLED;
}
/* Separate interrupt handling path for keyboard/mouse ports. */
static void
sunsu_change_speed(struct uart_port *port, unsigned int cflag,
unsigned int iflag, unsigned int quot);
static void sunsu_change_mouse_baud(struct uart_sunsu_port *up)
{
unsigned int cur_cflag = up->cflag;
int quot, new_baud;
up->cflag &= ~CBAUD;
up->cflag |= suncore_mouse_baud_cflag_next(cur_cflag, &new_baud);
quot = up->port.uartclk / (16 * new_baud);
sunsu_change_speed(&up->port, up->cflag, 0, quot);
}
static void receive_kbd_ms_chars(struct uart_sunsu_port *up, int is_break)
{
do {
unsigned char ch = serial_inp(up, UART_RX);
/* Stop-A is handled by drivers/char/keyboard.c now. */
if (up->su_type == SU_PORT_KBD) {
#ifdef CONFIG_SERIO
serio_interrupt(&up->serio, ch, 0);
#endif
} else if (up->su_type == SU_PORT_MS) {
int ret = suncore_mouse_baud_detection(ch, is_break);
switch (ret) {
case 2:
sunsu_change_mouse_baud(up);
/* fallthru */
case 1:
break;
case 0:
#ifdef CONFIG_SERIO
serio_interrupt(&up->serio, ch, 0);
#endif
break;
};
}
} while (serial_in(up, UART_LSR) & UART_LSR_DR);
}
static irqreturn_t sunsu_kbd_ms_interrupt(int irq, void *dev_id)
{
struct uart_sunsu_port *up = dev_id;
if (!(serial_in(up, UART_IIR) & UART_IIR_NO_INT)) {
unsigned char status = serial_inp(up, UART_LSR);
if ((status & UART_LSR_DR) || (status & UART_LSR_BI))
receive_kbd_ms_chars(up, (status & UART_LSR_BI) != 0);
}
return IRQ_HANDLED;
}
static unsigned int sunsu_tx_empty(struct uart_port *port)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
unsigned long flags;
unsigned int ret;
spin_lock_irqsave(&up->port.lock, flags);
ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
spin_unlock_irqrestore(&up->port.lock, flags);
return ret;
}
static unsigned int sunsu_get_mctrl(struct uart_port *port)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
unsigned char status;
unsigned int ret;
status = serial_in(up, UART_MSR);
ret = 0;
if (status & UART_MSR_DCD)
ret |= TIOCM_CAR;
if (status & UART_MSR_RI)
ret |= TIOCM_RNG;
if (status & UART_MSR_DSR)
ret |= TIOCM_DSR;
if (status & UART_MSR_CTS)
ret |= TIOCM_CTS;
return ret;
}
static void sunsu_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
unsigned char mcr = 0;
if (mctrl & TIOCM_RTS)
mcr |= UART_MCR_RTS;
if (mctrl & TIOCM_DTR)
mcr |= UART_MCR_DTR;
if (mctrl & TIOCM_OUT1)
mcr |= UART_MCR_OUT1;
if (mctrl & TIOCM_OUT2)
mcr |= UART_MCR_OUT2;
if (mctrl & TIOCM_LOOP)
mcr |= UART_MCR_LOOP;
serial_out(up, UART_MCR, mcr);
}
static void sunsu_break_ctl(struct uart_port *port, int break_state)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
unsigned long flags;
spin_lock_irqsave(&up->port.lock, flags);
if (break_state == -1)
up->lcr |= UART_LCR_SBC;
else
up->lcr &= ~UART_LCR_SBC;
serial_out(up, UART_LCR, up->lcr);
spin_unlock_irqrestore(&up->port.lock, flags);
}
static int sunsu_startup(struct uart_port *port)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
unsigned long flags;
int retval;
if (up->port.type == PORT_16C950) {
/* Wake up and initialize UART */
up->acr = 0;
serial_outp(up, UART_LCR, 0xBF);
serial_outp(up, UART_EFR, UART_EFR_ECB);
serial_outp(up, UART_IER, 0);
serial_outp(up, UART_LCR, 0);
serial_icr_write(up, UART_CSR, 0); /* Reset the UART */
serial_outp(up, UART_LCR, 0xBF);
serial_outp(up, UART_EFR, UART_EFR_ECB);
serial_outp(up, UART_LCR, 0);
}
#ifdef CONFIG_SERIAL_8250_RSA
/*
* If this is an RSA port, see if we can kick it up to the
* higher speed clock.
*/
enable_rsa(up);
#endif
/*
* Clear the FIFO buffers and disable them.
* (they will be reenabled in set_termios())
*/
if (uart_config[up->port.type].flags & UART_CLEAR_FIFO) {
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
serial_outp(up, UART_FCR, 0);
}
/*
* Clear the interrupt registers.
*/
(void) serial_inp(up, UART_LSR);
(void) serial_inp(up, UART_RX);
(void) serial_inp(up, UART_IIR);
(void) serial_inp(up, UART_MSR);
/*
* At this point, there's no way the LSR could still be 0xff;
* if it is, then bail out, because there's likely no UART
* here.
*/
if (!(up->port.flags & UPF_BUGGY_UART) &&
(serial_inp(up, UART_LSR) == 0xff)) {
printk("ttyS%d: LSR safety check engaged!\n", up->port.line);
return -ENODEV;
}
if (up->su_type != SU_PORT_PORT) {
retval = request_irq(up->port.irq, sunsu_kbd_ms_interrupt,
IRQF_SHARED, su_typev[up->su_type], up);
} else {
retval = request_irq(up->port.irq, sunsu_serial_interrupt,
IRQF_SHARED, su_typev[up->su_type], up);
}
if (retval) {
printk("su: Cannot register IRQ %d\n", up->port.irq);
return retval;
}
/*
* Now, initialize the UART
*/
serial_outp(up, UART_LCR, UART_LCR_WLEN8);
spin_lock_irqsave(&up->port.lock, flags);
up->port.mctrl |= TIOCM_OUT2;
sunsu_set_mctrl(&up->port, up->port.mctrl);
spin_unlock_irqrestore(&up->port.lock, flags);
/*
* Finally, enable interrupts. Note: Modem status interrupts
* are set via set_termios(), which will be occurring imminently
* anyway, so we don't enable them here.
*/
up->ier = UART_IER_RLSI | UART_IER_RDI;
serial_outp(up, UART_IER, up->ier);
if (up->port.flags & UPF_FOURPORT) {
unsigned int icp;
/*
* Enable interrupts on the AST Fourport board
*/
icp = (up->port.iobase & 0xfe0) | 0x01f;
outb_p(0x80, icp);
(void) inb_p(icp);
}
/*
* And clear the interrupt registers again for luck.
*/
(void) serial_inp(up, UART_LSR);
(void) serial_inp(up, UART_RX);
(void) serial_inp(up, UART_IIR);
(void) serial_inp(up, UART_MSR);
return 0;
}
static void sunsu_shutdown(struct uart_port *port)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
unsigned long flags;
/*
* Disable interrupts from this port
*/
up->ier = 0;
serial_outp(up, UART_IER, 0);
spin_lock_irqsave(&up->port.lock, flags);
if (up->port.flags & UPF_FOURPORT) {
/* reset interrupts on the AST Fourport board */
inb((up->port.iobase & 0xfe0) | 0x1f);
up->port.mctrl |= TIOCM_OUT1;
} else
up->port.mctrl &= ~TIOCM_OUT2;
sunsu_set_mctrl(&up->port, up->port.mctrl);
spin_unlock_irqrestore(&up->port.lock, flags);
/*
* Disable break condition and FIFOs
*/
serial_out(up, UART_LCR, serial_inp(up, UART_LCR) & ~UART_LCR_SBC);
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
UART_FCR_CLEAR_RCVR |
UART_FCR_CLEAR_XMIT);
serial_outp(up, UART_FCR, 0);
#ifdef CONFIG_SERIAL_8250_RSA
/*
* Reset the RSA board back to 115kbps compat mode.
*/
disable_rsa(up);
#endif
/*
* Read data port to reset things.
*/
(void) serial_in(up, UART_RX);
free_irq(up->port.irq, up);
}
static void
sunsu_change_speed(struct uart_port *port, unsigned int cflag,
unsigned int iflag, unsigned int quot)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
unsigned char cval, fcr = 0;
unsigned long flags;
switch (cflag & CSIZE) {
case CS5:
cval = 0x00;
break;
case CS6:
cval = 0x01;
break;
case CS7:
cval = 0x02;
break;
default:
case CS8:
cval = 0x03;
break;
}
if (cflag & CSTOPB)
cval |= 0x04;
if (cflag & PARENB)
cval |= UART_LCR_PARITY;
if (!(cflag & PARODD))
cval |= UART_LCR_EPAR;
#ifdef CMSPAR
if (cflag & CMSPAR)
cval |= UART_LCR_SPAR;
#endif
/*
* Work around a bug in the Oxford Semiconductor 952 rev B
* chip which causes it to seriously miscalculate baud rates
* when DLL is 0.
*/
if ((quot & 0xff) == 0 && up->port.type == PORT_16C950 &&
up->rev == 0x5201)
quot ++;
if (uart_config[up->port.type].flags & UART_USE_FIFO) {
if ((up->port.uartclk / quot) < (2400 * 16))
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1;
#ifdef CONFIG_SERIAL_8250_RSA
else if (up->port.type == PORT_RSA)
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_14;
#endif
else
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_8;
}
if (up->port.type == PORT_16750)
fcr |= UART_FCR7_64BYTE;
/*
* Ok, we're now changing the port state. Do it with
* interrupts disabled.
*/
spin_lock_irqsave(&up->port.lock, flags);
/*
* Update the per-port timeout.
*/
uart_update_timeout(port, cflag, (port->uartclk / (16 * quot)));
up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
if (iflag & INPCK)
up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
if (iflag & (BRKINT | PARMRK))
up->port.read_status_mask |= UART_LSR_BI;
/*
* Characteres to ignore
*/
up->port.ignore_status_mask = 0;
if (iflag & IGNPAR)
up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
if (iflag & IGNBRK) {
up->port.ignore_status_mask |= UART_LSR_BI;
/*
* If we're ignoring parity and break indicators,
* ignore overruns too (for real raw support).
*/
if (iflag & IGNPAR)
up->port.ignore_status_mask |= UART_LSR_OE;
}
/*
* ignore all characters if CREAD is not set
*/
if ((cflag & CREAD) == 0)
up->port.ignore_status_mask |= UART_LSR_DR;
/*
* CTS flow control flag and modem status interrupts
*/
up->ier &= ~UART_IER_MSI;
if (UART_ENABLE_MS(&up->port, cflag))
up->ier |= UART_IER_MSI;
serial_out(up, UART_IER, up->ier);
if (uart_config[up->port.type].flags & UART_STARTECH) {
serial_outp(up, UART_LCR, 0xBF);
serial_outp(up, UART_EFR, cflag & CRTSCTS ? UART_EFR_CTS :0);
}
serial_outp(up, UART_LCR, cval | UART_LCR_DLAB);/* set DLAB */
serial_outp(up, UART_DLL, quot & 0xff); /* LS of divisor */
serial_outp(up, UART_DLM, quot >> 8); /* MS of divisor */
if (up->port.type == PORT_16750)
serial_outp(up, UART_FCR, fcr); /* set fcr */
serial_outp(up, UART_LCR, cval); /* reset DLAB */
up->lcr = cval; /* Save LCR */
if (up->port.type != PORT_16750) {
if (fcr & UART_FCR_ENABLE_FIFO) {
/* emulated UARTs (Lucent Venus 167x) need two steps */
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
}
serial_outp(up, UART_FCR, fcr); /* set fcr */
}
up->cflag = cflag;
spin_unlock_irqrestore(&up->port.lock, flags);
}
static void
sunsu_set_termios(struct uart_port *port, struct termios *termios,
struct termios *old)
{
unsigned int baud, quot;
/*
* Ask the core to calculate the divisor for us.
*/
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
quot = uart_get_divisor(port, baud);
sunsu_change_speed(port, termios->c_cflag, termios->c_iflag, quot);
}
static void sunsu_release_port(struct uart_port *port)
{
}
static int sunsu_request_port(struct uart_port *port)
{
return 0;
}
static void sunsu_config_port(struct uart_port *port, int flags)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
if (flags & UART_CONFIG_TYPE) {
/*
* We are supposed to call autoconfig here, but this requires
* splitting all the OBP probing crap from the UART probing.
* We'll do it when we kill sunsu.c altogether.
*/
port->type = up->type_probed; /* XXX */
}
}
static int
sunsu_verify_port(struct uart_port *port, struct serial_struct *ser)
{
return -EINVAL;
}
static const char *
sunsu_type(struct uart_port *port)
{
int type = port->type;
if (type >= ARRAY_SIZE(uart_config))
type = 0;
return uart_config[type].name;
}
static struct uart_ops sunsu_pops = {
.tx_empty = sunsu_tx_empty,
.set_mctrl = sunsu_set_mctrl,
.get_mctrl = sunsu_get_mctrl,
.stop_tx = sunsu_stop_tx,
.start_tx = sunsu_start_tx,
.stop_rx = sunsu_stop_rx,
.enable_ms = sunsu_enable_ms,
.break_ctl = sunsu_break_ctl,
.startup = sunsu_startup,
.shutdown = sunsu_shutdown,
.set_termios = sunsu_set_termios,
.type = sunsu_type,
.release_port = sunsu_release_port,
.request_port = sunsu_request_port,
.config_port = sunsu_config_port,
.verify_port = sunsu_verify_port,
};
#define UART_NR 4
static struct uart_sunsu_port sunsu_ports[UART_NR];
#ifdef CONFIG_SERIO
static DEFINE_SPINLOCK(sunsu_serio_lock);
static int sunsu_serio_write(struct serio *serio, unsigned char ch)
{
struct uart_sunsu_port *up = serio->port_data;
unsigned long flags;
int lsr;
spin_lock_irqsave(&sunsu_serio_lock, flags);
do {
lsr = serial_in(up, UART_LSR);
} while (!(lsr & UART_LSR_THRE));
/* Send the character out. */
serial_out(up, UART_TX, ch);
spin_unlock_irqrestore(&sunsu_serio_lock, flags);
return 0;
}
static int sunsu_serio_open(struct serio *serio)
{
struct uart_sunsu_port *up = serio->port_data;
unsigned long flags;
int ret;
spin_lock_irqsave(&sunsu_serio_lock, flags);
if (!up->serio_open) {
up->serio_open = 1;
ret = 0;
} else
ret = -EBUSY;
spin_unlock_irqrestore(&sunsu_serio_lock, flags);
return ret;
}
static void sunsu_serio_close(struct serio *serio)
{
struct uart_sunsu_port *up = serio->port_data;
unsigned long flags;
spin_lock_irqsave(&sunsu_serio_lock, flags);
up->serio_open = 0;
spin_unlock_irqrestore(&sunsu_serio_lock, flags);
}
#endif /* CONFIG_SERIO */
static void sunsu_autoconfig(struct uart_sunsu_port *up)
{
unsigned char status1, status2, scratch, scratch2, scratch3;
unsigned char save_lcr, save_mcr;
unsigned long flags;
if (up->su_type == SU_PORT_NONE)
return;
up->type_probed = PORT_UNKNOWN;
up->port.iotype = UPIO_MEM;
spin_lock_irqsave(&up->port.lock, flags);
if (!(up->port.flags & UPF_BUGGY_UART)) {
/*
* Do a simple existence test first; if we fail this, there's
* no point trying anything else.
*
* 0x80 is used as a nonsense port to prevent against false
* positives due to ISA bus float. The assumption is that
* 0x80 is a non-existent port; which should be safe since
* include/asm/io.h also makes this assumption.
*/
scratch = serial_inp(up, UART_IER);
serial_outp(up, UART_IER, 0);
#ifdef __i386__
outb(0xff, 0x080);
#endif
scratch2 = serial_inp(up, UART_IER);
serial_outp(up, UART_IER, 0x0f);
#ifdef __i386__
outb(0, 0x080);
#endif
scratch3 = serial_inp(up, UART_IER);
serial_outp(up, UART_IER, scratch);
if (scratch2 != 0 || scratch3 != 0x0F)
goto out; /* We failed; there's nothing here */
}
save_mcr = serial_in(up, UART_MCR);
save_lcr = serial_in(up, UART_LCR);
/*
* Check to see if a UART is really there. Certain broken
* internal modems based on the Rockwell chipset fail this
* test, because they apparently don't implement the loopback
* test mode. So this test is skipped on the COM 1 through
* COM 4 ports. This *should* be safe, since no board
* manufacturer would be stupid enough to design a board
* that conflicts with COM 1-4 --- we hope!
*/
if (!(up->port.flags & UPF_SKIP_TEST)) {
serial_outp(up, UART_MCR, UART_MCR_LOOP | 0x0A);
status1 = serial_inp(up, UART_MSR) & 0xF0;
serial_outp(up, UART_MCR, save_mcr);
if (status1 != 0x90)
goto out; /* We failed loopback test */
}
serial_outp(up, UART_LCR, 0xBF); /* set up for StarTech test */
serial_outp(up, UART_EFR, 0); /* EFR is the same as FCR */
serial_outp(up, UART_LCR, 0);
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
scratch = serial_in(up, UART_IIR) >> 6;
switch (scratch) {
case 0:
up->port.type = PORT_16450;
break;
case 1:
up->port.type = PORT_UNKNOWN;
break;
case 2:
up->port.type = PORT_16550;
break;
case 3:
up->port.type = PORT_16550A;
break;
}
if (up->port.type == PORT_16550A) {
/* Check for Startech UART's */
serial_outp(up, UART_LCR, UART_LCR_DLAB);
if (serial_in(up, UART_EFR) == 0) {
up->port.type = PORT_16650;
} else {
serial_outp(up, UART_LCR, 0xBF);
if (serial_in(up, UART_EFR) == 0)
up->port.type = PORT_16650V2;
}
}
if (up->port.type == PORT_16550A) {
/* Check for TI 16750 */
serial_outp(up, UART_LCR, save_lcr | UART_LCR_DLAB);
serial_outp(up, UART_FCR,
UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
scratch = serial_in(up, UART_IIR) >> 5;
if (scratch == 7) {
/*
* If this is a 16750, and not a cheap UART
* clone, then it should only go into 64 byte
* mode if the UART_FCR7_64BYTE bit was set
* while UART_LCR_DLAB was latched.
*/
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
serial_outp(up, UART_LCR, 0);
serial_outp(up, UART_FCR,
UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
scratch = serial_in(up, UART_IIR) >> 5;
if (scratch == 6)
up->port.type = PORT_16750;
}
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
}
serial_outp(up, UART_LCR, save_lcr);
if (up->port.type == PORT_16450) {
scratch = serial_in(up, UART_SCR);
serial_outp(up, UART_SCR, 0xa5);
status1 = serial_in(up, UART_SCR);
serial_outp(up, UART_SCR, 0x5a);
status2 = serial_in(up, UART_SCR);
serial_outp(up, UART_SCR, scratch);
if ((status1 != 0xa5) || (status2 != 0x5a))
up->port.type = PORT_8250;
}
up->port.fifosize = uart_config[up->port.type].dfl_xmit_fifo_size;
if (up->port.type == PORT_UNKNOWN)
goto out;
up->type_probed = up->port.type; /* XXX */
/*
* Reset the UART.
*/
#ifdef CONFIG_SERIAL_8250_RSA
if (up->port.type == PORT_RSA)
serial_outp(up, UART_RSA_FRR, 0);
#endif
serial_outp(up, UART_MCR, save_mcr);
serial_outp(up, UART_FCR, (UART_FCR_ENABLE_FIFO |
UART_FCR_CLEAR_RCVR |
UART_FCR_CLEAR_XMIT));
serial_outp(up, UART_FCR, 0);
(void)serial_in(up, UART_RX);
serial_outp(up, UART_IER, 0);
out:
spin_unlock_irqrestore(&up->port.lock, flags);
}
static struct uart_driver sunsu_reg = {
.owner = THIS_MODULE,
.driver_name = "serial",
.dev_name = "ttyS",
.major = TTY_MAJOR,
};
static int __init sunsu_kbd_ms_init(struct uart_sunsu_port *up)
{
int quot, baud;
#ifdef CONFIG_SERIO
struct serio *serio;
#endif
if (up->su_type == SU_PORT_KBD) {
up->cflag = B1200 | CS8 | CLOCAL | CREAD;
baud = 1200;
} else {
up->cflag = B4800 | CS8 | CLOCAL | CREAD;
baud = 4800;
}
quot = up->port.uartclk / (16 * baud);
sunsu_autoconfig(up);
if (up->port.type == PORT_UNKNOWN)
return -ENODEV;
printk("%s: %s port at %lx, irq %u\n",
to_of_device(up->port.dev)->node->full_name,
(up->su_type == SU_PORT_KBD) ? "Keyboard" : "Mouse",
up->port.mapbase, up->port.irq);
#ifdef CONFIG_SERIO
serio = &up->serio;
serio->port_data = up;
serio->id.type = SERIO_RS232;
if (up->su_type == SU_PORT_KBD) {
serio->id.proto = SERIO_SUNKBD;
strlcpy(serio->name, "sukbd", sizeof(serio->name));
} else {
serio->id.proto = SERIO_SUN;
serio->id.extra = 1;
strlcpy(serio->name, "sums", sizeof(serio->name));
}
strlcpy(serio->phys,
(!(up->port.line & 1) ? "su/serio0" : "su/serio1"),
sizeof(serio->phys));
serio->write = sunsu_serio_write;
serio->open = sunsu_serio_open;
serio->close = sunsu_serio_close;
serio->dev.parent = up->port.dev;
serio_register_port(serio);
#endif
sunsu_change_speed(&up->port, up->cflag, 0, quot);
sunsu_startup(&up->port);
return 0;
}
/*
* ------------------------------------------------------------
* Serial console driver
* ------------------------------------------------------------
*/
#ifdef CONFIG_SERIAL_SUNSU_CONSOLE
#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
/*
* Wait for transmitter & holding register to empty
*/
static __inline__ void wait_for_xmitr(struct uart_sunsu_port *up)
{
unsigned int status, tmout = 10000;
/* Wait up to 10ms for the character(s) to be sent. */
do {
status = serial_in(up, UART_LSR);
if (status & UART_LSR_BI)
up->lsr_break_flag = UART_LSR_BI;
if (--tmout == 0)
break;
udelay(1);
} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
/* Wait up to 1s for flow control if necessary */
if (up->port.flags & UPF_CONS_FLOW) {
tmout = 1000000;
while (--tmout &&
((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
udelay(1);
}
}
static void sunsu_console_putchar(struct uart_port *port, int ch)
{
struct uart_sunsu_port *up = (struct uart_sunsu_port *)port;
wait_for_xmitr(up);
serial_out(up, UART_TX, ch);
}
/*
* Print a string to the serial port trying not to disturb
* any possible real use of the port...
*/
static void sunsu_console_write(struct console *co, const char *s,
unsigned int count)
{
struct uart_sunsu_port *up = &sunsu_ports[co->index];
unsigned int ier;
/*
* First save the UER then disable the interrupts
*/
ier = serial_in(up, UART_IER);
serial_out(up, UART_IER, 0);
uart_console_write(&up->port, s, count, sunsu_console_putchar);
/*
* Finally, wait for transmitter to become empty
* and restore the IER
*/
wait_for_xmitr(up);
serial_out(up, UART_IER, ier);
}
/*
* Setup initial baud/bits/parity. We do two things here:
* - construct a cflag setting for the first su_open()
* - initialize the serial port
* Return non-zero if we didn't find a serial port.
*/
static int sunsu_console_setup(struct console *co, char *options)
{
struct uart_port *port;
int baud = 9600;
int bits = 8;
int parity = 'n';
int flow = 'n';
printk("Console: ttyS%d (SU)\n",
(sunsu_reg.minor - 64) + co->index);
/*
* Check whether an invalid uart number has been specified, and
* if so, search for the first available port that does have
* console support.
*/
if (co->index >= UART_NR)
co->index = 0;
port = &sunsu_ports[co->index].port;
/*
* Temporary fix.
*/
spin_lock_init(&port->lock);
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
return uart_set_options(port, co, baud, parity, bits, flow);
}
static struct console sunsu_cons = {
.name = "ttyS",
.write = sunsu_console_write,
.device = uart_console_device,
.setup = sunsu_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &sunsu_reg,
};
/*
* Register console.
*/
static inline struct console *SUNSU_CONSOLE(int num_uart)
{
int i;
if (con_is_present())
return NULL;
for (i = 0; i < num_uart; i++) {
int this_minor = sunsu_reg.minor + i;
if ((this_minor - 64) == (serial_console - 1))
break;
}
if (i == num_uart)
return NULL;
sunsu_cons.index = i;
return &sunsu_cons;
}
#else
#define SUNSU_CONSOLE(num_uart) (NULL)
#define sunsu_serial_console_init() do { } while (0)
#endif
static enum su_type __devinit su_get_type(struct device_node *dp)
{
struct device_node *ap = of_find_node_by_path("/aliases");
if (ap) {
char *keyb = of_get_property(ap, "keyboard", NULL);
char *ms = of_get_property(ap, "mouse", NULL);
if (keyb) {
if (dp == of_find_node_by_path(keyb))
return SU_PORT_KBD;
}
if (ms) {
if (dp == of_find_node_by_path(ms))
return SU_PORT_MS;
}
}
return SU_PORT_PORT;
}
static int __devinit su_probe(struct of_device *op, const struct of_device_id *match)
{
static int inst;
struct device_node *dp = op->node;
struct uart_sunsu_port *up;
struct resource *rp;
enum su_type type;
int err;
type = su_get_type(dp);
if (type == SU_PORT_PORT) {
if (inst >= UART_NR)
return -EINVAL;
up = &sunsu_ports[inst];
} else {
up = kzalloc(sizeof(*up), GFP_KERNEL);
if (!up)
return -ENOMEM;
}
up->port.line = inst;
spin_lock_init(&up->port.lock);
up->su_type = type;
rp = &op->resource[0];
up->port.mapbase = rp->start;
up->reg_size = (rp->end - rp->start) + 1;
up->port.membase = of_ioremap(rp, 0, up->reg_size, "su");
if (!up->port.membase) {
if (type != SU_PORT_PORT)
kfree(up);
return -ENOMEM;
}
up->port.irq = op->irqs[0];
up->port.dev = &op->dev;
up->port.type = PORT_UNKNOWN;
up->port.uartclk = (SU_BASE_BAUD * 16);
err = 0;
if (up->su_type == SU_PORT_KBD || up->su_type == SU_PORT_MS) {
err = sunsu_kbd_ms_init(up);
if (err) {
kfree(up);
goto out_unmap;
}
dev_set_drvdata(&op->dev, up);
return 0;
}
up->port.flags |= UPF_BOOT_AUTOCONF;
sunsu_autoconfig(up);
err = -ENODEV;
if (up->port.type == PORT_UNKNOWN)
goto out_unmap;
up->port.ops = &sunsu_pops;
err = uart_add_one_port(&sunsu_reg, &up->port);
if (err)
goto out_unmap;
dev_set_drvdata(&op->dev, up);
inst++;
return 0;
out_unmap:
of_iounmap(up->port.membase, up->reg_size);
return err;
}
static int __devexit su_remove(struct of_device *dev)
{
struct uart_sunsu_port *up = dev_get_drvdata(&dev->dev);;
if (up->su_type == SU_PORT_MS ||
up->su_type == SU_PORT_KBD) {
#ifdef CONFIG_SERIO
serio_unregister_port(&up->serio);
#endif
kfree(up);
} else if (up->port.type != PORT_UNKNOWN) {
uart_remove_one_port(&sunsu_reg, &up->port);
}
if (up->port.membase)
of_iounmap(up->port.membase, up->reg_size);
dev_set_drvdata(&dev->dev, NULL);
return 0;
}
static struct of_device_id su_match[] = {
{
.name = "su",
},
{
.name = "su_pnp",
},
{
.name = "serial",
.compatible = "su",
},
{},
};
MODULE_DEVICE_TABLE(of, su_match);
static struct of_platform_driver su_driver = {
.name = "su",
.match_table = su_match,
.probe = su_probe,
.remove = __devexit_p(su_remove),
};
static int num_uart;
static int __init sunsu_init(void)
{
struct device_node *dp;
int err;
num_uart = 0;
for_each_node_by_name(dp, "su") {
if (su_get_type(dp) == SU_PORT_PORT)
num_uart++;
}
for_each_node_by_name(dp, "su_pnp") {
if (su_get_type(dp) == SU_PORT_PORT)
num_uart++;
}
for_each_node_by_name(dp, "serial") {
if (of_device_is_compatible(dp, "su")) {
if (su_get_type(dp) == SU_PORT_PORT)
num_uart++;
}
}
if (num_uart) {
sunsu_reg.minor = sunserial_current_minor;
sunsu_reg.nr = num_uart;
err = uart_register_driver(&sunsu_reg);
if (err)
return err;
sunsu_reg.tty_driver->name_base = sunsu_reg.minor - 64;
sunserial_current_minor += num_uart;
sunsu_reg.cons = SUNSU_CONSOLE(num_uart);
}
err = of_register_driver(&su_driver, &of_bus_type);
if (err && num_uart)
uart_unregister_driver(&sunsu_reg);
return err;
}
static void __exit sunsu_exit(void)
{
if (num_uart)
uart_unregister_driver(&sunsu_reg);
}
module_init(sunsu_init);
module_exit(sunsu_exit);
MODULE_AUTHOR("Eddie C. Dost, Peter Zaitcev, and David S. Miller");
MODULE_DESCRIPTION("Sun SU serial port driver");
MODULE_VERSION("2.0");
MODULE_LICENSE("GPL");
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