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linux/drivers/serial/pmac_zilog.c
Russell King b129a8ccd5 [SERIAL] Clean up and fix tty transmission start/stoping 
The start_tx and stop_tx methods were passed a flag to indicate
whether the start/stop was from the tty start/stop callbacks, and
some drivers used this flag to decide whether to ask the UART to
immediately stop transmission (where the UART supports such a
feature.)

There are other cases when we wish this to occur - when CTS is
lowered, or if we change from soft to hard flow control and CTS
is inactive.  In these cases, this flag was false, and we would
allow the transmitter to drain before stopping.

There is really only one case where we want to let the transmitter
drain before disabling, and that's when we run out of characters
to send.

Hence, re-jig the start_tx and stop_tx methods to eliminate this
flag, and introduce new functions for the special "disable and
allow transmitter to drain" case.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-08-31 10:12:14 +01:00

2045 lines
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/*
* linux/drivers/serial/pmac_zilog.c
*
* Driver for PowerMac Z85c30 based ESCC cell found in the
* "macio" ASICs of various PowerMac models
*
* Copyright (C) 2003 Ben. Herrenschmidt (benh@kernel.crashing.org)
*
* Derived from drivers/macintosh/macserial.c by Paul Mackerras
* and drivers/serial/sunzilog.c by David S. Miller
*
* Hrm... actually, I ripped most of sunzilog (Thanks David !) and
* adapted special tweaks needed for us. I don't think it's worth
* merging back those though. The DMA code still has to get in
* and once done, I expect that driver to remain fairly stable in
* the long term, unless we change the driver model again...
*
* 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
*
* 2004-08-06 Harald Welte <laforge@gnumonks.org>
* - Enable BREAK interrupt
* - Add support for sysreq
*
* TODO: - Add DMA support
* - Defer port shutdown to a few seconds after close
* - maybe put something right into uap->clk_divisor
*/
#undef DEBUG
#undef DEBUG_HARD
#undef USE_CTRL_O_SYSRQ
#include <linux/config.h>
#include <linux/module.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/slab.h>
#include <linux/adb.h>
#include <linux/pmu.h>
#include <linux/bitops.h>
#include <linux/sysrq.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/pmac_feature.h>
#include <asm/dbdma.h>
#include <asm/macio.h>
#include <asm/semaphore.h>
#if defined (CONFIG_SERIAL_PMACZILOG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/serial.h>
#include <linux/serial_core.h>
#include "pmac_zilog.h"
/* Not yet implemented */
#undef HAS_DBDMA
static char version[] __initdata = "pmac_zilog: 0.6 (Benjamin Herrenschmidt <benh@kernel.crashing.org>)";
MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
MODULE_DESCRIPTION("Driver for the PowerMac serial ports.");
MODULE_LICENSE("GPL");
#define PWRDBG(fmt, arg...) printk(KERN_DEBUG fmt , ## arg)
/*
* For the sake of early serial console, we can do a pre-probe
* (optional) of the ports at rather early boot time.
*/
static struct uart_pmac_port pmz_ports[MAX_ZS_PORTS];
static int pmz_ports_count;
static DECLARE_MUTEX(pmz_irq_sem);
static struct uart_driver pmz_uart_reg = {
.owner = THIS_MODULE,
.driver_name = "ttyS",
.devfs_name = "tts/",
.dev_name = "ttyS",
.major = TTY_MAJOR,
};
/*
* Load all registers to reprogram the port
* This function must only be called when the TX is not busy. The UART
* port lock must be held and local interrupts disabled.
*/
static void pmz_load_zsregs(struct uart_pmac_port *uap, u8 *regs)
{
int i;
if (ZS_IS_ASLEEP(uap))
return;
/* Let pending transmits finish. */
for (i = 0; i < 1000; i++) {
unsigned char stat = read_zsreg(uap, R1);
if (stat & ALL_SNT)
break;
udelay(100);
}
ZS_CLEARERR(uap);
zssync(uap);
ZS_CLEARFIFO(uap);
zssync(uap);
ZS_CLEARERR(uap);
/* Disable all interrupts. */
write_zsreg(uap, R1,
regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
/* Set parity, sync config, stop bits, and clock divisor. */
write_zsreg(uap, R4, regs[R4]);
/* Set misc. TX/RX control bits. */
write_zsreg(uap, R10, regs[R10]);
/* Set TX/RX controls sans the enable bits. */
write_zsreg(uap, R3, regs[R3] & ~RxENABLE);
write_zsreg(uap, R5, regs[R5] & ~TxENABLE);
/* now set R7 "prime" on ESCC */
write_zsreg(uap, R15, regs[R15] | EN85C30);
write_zsreg(uap, R7, regs[R7P]);
/* make sure we use R7 "non-prime" on ESCC */
write_zsreg(uap, R15, regs[R15] & ~EN85C30);
/* Synchronous mode config. */
write_zsreg(uap, R6, regs[R6]);
write_zsreg(uap, R7, regs[R7]);
/* Disable baud generator. */
write_zsreg(uap, R14, regs[R14] & ~BRENAB);
/* Clock mode control. */
write_zsreg(uap, R11, regs[R11]);
/* Lower and upper byte of baud rate generator divisor. */
write_zsreg(uap, R12, regs[R12]);
write_zsreg(uap, R13, regs[R13]);
/* Now rewrite R14, with BRENAB (if set). */
write_zsreg(uap, R14, regs[R14]);
/* Reset external status interrupts. */
write_zsreg(uap, R0, RES_EXT_INT);
write_zsreg(uap, R0, RES_EXT_INT);
/* Rewrite R3/R5, this time without enables masked. */
write_zsreg(uap, R3, regs[R3]);
write_zsreg(uap, R5, regs[R5]);
/* Rewrite R1, this time without IRQ enabled masked. */
write_zsreg(uap, R1, regs[R1]);
/* Enable interrupts */
write_zsreg(uap, R9, regs[R9]);
}
/*
* We do like sunzilog to avoid disrupting pending Tx
* Reprogram the Zilog channel HW registers with the copies found in the
* software state struct. If the transmitter is busy, we defer this update
* until the next TX complete interrupt. Else, we do it right now.
*
* The UART port lock must be held and local interrupts disabled.
*/
static void pmz_maybe_update_regs(struct uart_pmac_port *uap)
{
if (!ZS_REGS_HELD(uap)) {
if (ZS_TX_ACTIVE(uap)) {
uap->flags |= PMACZILOG_FLAG_REGS_HELD;
} else {
pmz_debug("pmz: maybe_update_regs: updating\n");
pmz_load_zsregs(uap, uap->curregs);
}
}
}
static struct tty_struct *pmz_receive_chars(struct uart_pmac_port *uap,
struct pt_regs *regs)
{
struct tty_struct *tty = NULL;
unsigned char ch, r1, drop, error;
int loops = 0;
retry:
/* The interrupt can be enabled when the port isn't open, typically
* that happens when using one port is open and the other closed (stale
* interrupt) or when one port is used as a console.
*/
if (!ZS_IS_OPEN(uap)) {
pmz_debug("pmz: draining input\n");
/* Port is closed, drain input data */
for (;;) {
if ((++loops) > 1000)
goto flood;
(void)read_zsreg(uap, R1);
write_zsreg(uap, R0, ERR_RES);
(void)read_zsdata(uap);
ch = read_zsreg(uap, R0);
if (!(ch & Rx_CH_AV))
break;
}
return NULL;
}
/* Sanity check, make sure the old bug is no longer happening */
if (uap->port.info == NULL || uap->port.info->tty == NULL) {
WARN_ON(1);
(void)read_zsdata(uap);
return NULL;
}
tty = uap->port.info->tty;
while (1) {
error = 0;
drop = 0;
if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) {
/* Have to drop the lock here */
pmz_debug("pmz: flip overflow\n");
spin_unlock(&uap->port.lock);
tty->flip.work.func((void *)tty);
spin_lock(&uap->port.lock);
if (tty->flip.count >= TTY_FLIPBUF_SIZE)
drop = 1;
if (ZS_IS_ASLEEP(uap))
return NULL;
if (!ZS_IS_OPEN(uap))
goto retry;
}
r1 = read_zsreg(uap, R1);
ch = read_zsdata(uap);
if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
write_zsreg(uap, R0, ERR_RES);
zssync(uap);
}
ch &= uap->parity_mask;
if (ch == 0 && uap->flags & PMACZILOG_FLAG_BREAK) {
uap->flags &= ~PMACZILOG_FLAG_BREAK;
}
#if defined(CONFIG_MAGIC_SYSRQ) && defined(CONFIG_SERIAL_CORE_CONSOLE)
#ifdef USE_CTRL_O_SYSRQ
/* Handle the SysRq ^O Hack */
if (ch == '\x0f') {
uap->port.sysrq = jiffies + HZ*5;
goto next_char;
}
#endif /* USE_CTRL_O_SYSRQ */
if (uap->port.sysrq) {
int swallow;
spin_unlock(&uap->port.lock);
swallow = uart_handle_sysrq_char(&uap->port, ch, regs);
spin_lock(&uap->port.lock);
if (swallow)
goto next_char;
}
#endif /* CONFIG_MAGIC_SYSRQ && CONFIG_SERIAL_CORE_CONSOLE */
/* A real serial line, record the character and status. */
if (drop)
goto next_char;
*tty->flip.char_buf_ptr = ch;
*tty->flip.flag_buf_ptr = TTY_NORMAL;
uap->port.icount.rx++;
if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {
error = 1;
if (r1 & BRK_ABRT) {
pmz_debug("pmz: got break !\n");
r1 &= ~(PAR_ERR | CRC_ERR);
uap->port.icount.brk++;
if (uart_handle_break(&uap->port))
goto next_char;
}
else if (r1 & PAR_ERR)
uap->port.icount.parity++;
else if (r1 & CRC_ERR)
uap->port.icount.frame++;
if (r1 & Rx_OVR)
uap->port.icount.overrun++;
r1 &= uap->port.read_status_mask;
if (r1 & BRK_ABRT)
*tty->flip.flag_buf_ptr = TTY_BREAK;
else if (r1 & PAR_ERR)
*tty->flip.flag_buf_ptr = TTY_PARITY;
else if (r1 & CRC_ERR)
*tty->flip.flag_buf_ptr = TTY_FRAME;
}
if (uap->port.ignore_status_mask == 0xff ||
(r1 & uap->port.ignore_status_mask) == 0) {
tty->flip.flag_buf_ptr++;
tty->flip.char_buf_ptr++;
tty->flip.count++;
}
if ((r1 & Rx_OVR) &&
tty->flip.count < TTY_FLIPBUF_SIZE) {
*tty->flip.flag_buf_ptr = TTY_OVERRUN;
tty->flip.flag_buf_ptr++;
tty->flip.char_buf_ptr++;
tty->flip.count++;
}
next_char:
/* We can get stuck in an infinite loop getting char 0 when the
* line is in a wrong HW state, we break that here.
* When that happens, I disable the receive side of the driver.
* Note that what I've been experiencing is a real irq loop where
* I'm getting flooded regardless of the actual port speed.
* Something stange is going on with the HW
*/
if ((++loops) > 1000)
goto flood;
ch = read_zsreg(uap, R0);
if (!(ch & Rx_CH_AV))
break;
}
return tty;
flood:
uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
write_zsreg(uap, R1, uap->curregs[R1]);
zssync(uap);
dev_err(&uap->dev->ofdev.dev, "pmz: rx irq flood !\n");
return tty;
}
static void pmz_status_handle(struct uart_pmac_port *uap, struct pt_regs *regs)
{
unsigned char status;
status = read_zsreg(uap, R0);
write_zsreg(uap, R0, RES_EXT_INT);
zssync(uap);
if (ZS_IS_OPEN(uap) && ZS_WANTS_MODEM_STATUS(uap)) {
if (status & SYNC_HUNT)
uap->port.icount.dsr++;
/* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
* But it does not tell us which bit has changed, we have to keep
* track of this ourselves.
* The CTS input is inverted for some reason. -- paulus
*/
if ((status ^ uap->prev_status) & DCD)
uart_handle_dcd_change(&uap->port,
(status & DCD));
if ((status ^ uap->prev_status) & CTS)
uart_handle_cts_change(&uap->port,
!(status & CTS));
wake_up_interruptible(&uap->port.info->delta_msr_wait);
}
if (status & BRK_ABRT)
uap->flags |= PMACZILOG_FLAG_BREAK;
uap->prev_status = status;
}
static void pmz_transmit_chars(struct uart_pmac_port *uap)
{
struct circ_buf *xmit;
if (ZS_IS_ASLEEP(uap))
return;
if (ZS_IS_CONS(uap)) {
unsigned char status = read_zsreg(uap, R0);
/* TX still busy? Just wait for the next TX done interrupt.
*
* It can occur because of how we do serial console writes. It would
* be nice to transmit console writes just like we normally would for
* a TTY line. (ie. buffered and TX interrupt driven). That is not
* easy because console writes cannot sleep. One solution might be
* to poll on enough port->xmit space becomming free. -DaveM
*/
if (!(status & Tx_BUF_EMP))
return;
}
uap->flags &= ~PMACZILOG_FLAG_TX_ACTIVE;
if (ZS_REGS_HELD(uap)) {
pmz_load_zsregs(uap, uap->curregs);
uap->flags &= ~PMACZILOG_FLAG_REGS_HELD;
}
if (ZS_TX_STOPPED(uap)) {
uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
goto ack_tx_int;
}
if (uap->port.x_char) {
uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
write_zsdata(uap, uap->port.x_char);
zssync(uap);
uap->port.icount.tx++;
uap->port.x_char = 0;
return;
}
if (uap->port.info == NULL)
goto ack_tx_int;
xmit = &uap->port.info->xmit;
if (uart_circ_empty(xmit)) {
uart_write_wakeup(&uap->port);
goto ack_tx_int;
}
if (uart_tx_stopped(&uap->port))
goto ack_tx_int;
uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
write_zsdata(uap, xmit->buf[xmit->tail]);
zssync(uap);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
uap->port.icount.tx++;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&uap->port);
return;
ack_tx_int:
write_zsreg(uap, R0, RES_Tx_P);
zssync(uap);
}
/* Hrm... we register that twice, fixme later.... */
static irqreturn_t pmz_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
struct uart_pmac_port *uap = dev_id;
struct uart_pmac_port *uap_a;
struct uart_pmac_port *uap_b;
int rc = IRQ_NONE;
struct tty_struct *tty;
u8 r3;
uap_a = pmz_get_port_A(uap);
uap_b = uap_a->mate;
spin_lock(&uap_a->port.lock);
r3 = read_zsreg(uap_a, R3);
#ifdef DEBUG_HARD
pmz_debug("irq, r3: %x\n", r3);
#endif
/* Channel A */
tty = NULL;
if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
write_zsreg(uap_a, R0, RES_H_IUS);
zssync(uap_a);
if (r3 & CHAEXT)
pmz_status_handle(uap_a, regs);
if (r3 & CHARxIP)
tty = pmz_receive_chars(uap_a, regs);
if (r3 & CHATxIP)
pmz_transmit_chars(uap_a);
rc = IRQ_HANDLED;
}
spin_unlock(&uap_a->port.lock);
if (tty != NULL)
tty_flip_buffer_push(tty);
if (uap_b->node == NULL)
goto out;
spin_lock(&uap_b->port.lock);
tty = NULL;
if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
write_zsreg(uap_b, R0, RES_H_IUS);
zssync(uap_b);
if (r3 & CHBEXT)
pmz_status_handle(uap_b, regs);
if (r3 & CHBRxIP)
tty = pmz_receive_chars(uap_b, regs);
if (r3 & CHBTxIP)
pmz_transmit_chars(uap_b);
rc = IRQ_HANDLED;
}
spin_unlock(&uap_b->port.lock);
if (tty != NULL)
tty_flip_buffer_push(tty);
out:
#ifdef DEBUG_HARD
pmz_debug("irq done.\n");
#endif
return rc;
}
/*
* Peek the status register, lock not held by caller
*/
static inline u8 pmz_peek_status(struct uart_pmac_port *uap)
{
unsigned long flags;
u8 status;
spin_lock_irqsave(&uap->port.lock, flags);
status = read_zsreg(uap, R0);
spin_unlock_irqrestore(&uap->port.lock, flags);
return status;
}
/*
* Check if transmitter is empty
* The port lock is not held.
*/
static unsigned int pmz_tx_empty(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned char status;
if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
return TIOCSER_TEMT;
status = pmz_peek_status(to_pmz(port));
if (status & Tx_BUF_EMP)
return TIOCSER_TEMT;
return 0;
}
/*
* Set Modem Control (RTS & DTR) bits
* The port lock is held and interrupts are disabled.
* Note: Shall we really filter out RTS on external ports or
* should that be dealt at higher level only ?
*/
static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned char set_bits, clear_bits;
/* Do nothing for irda for now... */
if (ZS_IS_IRDA(uap))
return;
/* We get called during boot with a port not up yet */
if (ZS_IS_ASLEEP(uap) ||
!(ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)))
return;
set_bits = clear_bits = 0;
if (ZS_IS_INTMODEM(uap)) {
if (mctrl & TIOCM_RTS)
set_bits |= RTS;
else
clear_bits |= RTS;
}
if (mctrl & TIOCM_DTR)
set_bits |= DTR;
else
clear_bits |= DTR;
/* NOTE: Not subject to 'transmitter active' rule. */
uap->curregs[R5] |= set_bits;
uap->curregs[R5] &= ~clear_bits;
if (ZS_IS_ASLEEP(uap))
return;
write_zsreg(uap, R5, uap->curregs[R5]);
pmz_debug("pmz_set_mctrl: set bits: %x, clear bits: %x -> %x\n",
set_bits, clear_bits, uap->curregs[R5]);
zssync(uap);
}
/*
* Get Modem Control bits (only the input ones, the core will
* or that with a cached value of the control ones)
* The port lock is held and interrupts are disabled.
*/
static unsigned int pmz_get_mctrl(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned char status;
unsigned int ret;
if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
return 0;
status = read_zsreg(uap, R0);
ret = 0;
if (status & DCD)
ret |= TIOCM_CAR;
if (status & SYNC_HUNT)
ret |= TIOCM_DSR;
if (!(status & CTS))
ret |= TIOCM_CTS;
return ret;
}
/*
* Stop TX side. Dealt like sunzilog at next Tx interrupt,
* though for DMA, we will have to do a bit more.
* The port lock is held and interrupts are disabled.
*/
static void pmz_stop_tx(struct uart_port *port)
{
to_pmz(port)->flags |= PMACZILOG_FLAG_TX_STOPPED;
}
/*
* Kick the Tx side.
* The port lock is held and interrupts are disabled.
*/
static void pmz_start_tx(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned char status;
pmz_debug("pmz: start_tx()\n");
uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
return;
status = read_zsreg(uap, R0);
/* TX busy? Just wait for the TX done interrupt. */
if (!(status & Tx_BUF_EMP))
return;
/* Send the first character to jump-start the TX done
* IRQ sending engine.
*/
if (port->x_char) {
write_zsdata(uap, port->x_char);
zssync(uap);
port->icount.tx++;
port->x_char = 0;
} else {
struct circ_buf *xmit = &port->info->xmit;
write_zsdata(uap, xmit->buf[xmit->tail]);
zssync(uap);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&uap->port);
}
pmz_debug("pmz: start_tx() done.\n");
}
/*
* Stop Rx side, basically disable emitting of
* Rx interrupts on the port. We don't disable the rx
* side of the chip proper though
* The port lock is held.
*/
static void pmz_stop_rx(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
return;
pmz_debug("pmz: stop_rx()()\n");
/* Disable all RX interrupts. */
uap->curregs[R1] &= ~RxINT_MASK;
pmz_maybe_update_regs(uap);
pmz_debug("pmz: stop_rx() done.\n");
}
/*
* Enable modem status change interrupts
* The port lock is held.
*/
static void pmz_enable_ms(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned char new_reg;
if (ZS_IS_IRDA(uap) || uap->node == NULL)
return;
new_reg = uap->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
if (new_reg != uap->curregs[R15]) {
uap->curregs[R15] = new_reg;
if (ZS_IS_ASLEEP(uap))
return;
/* NOTE: Not subject to 'transmitter active' rule. */
write_zsreg(uap, R15, uap->curregs[R15]);
}
}
/*
* Control break state emission
* The port lock is not held.
*/
static void pmz_break_ctl(struct uart_port *port, int break_state)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned char set_bits, clear_bits, new_reg;
unsigned long flags;
if (uap->node == NULL)
return;
set_bits = clear_bits = 0;
if (break_state)
set_bits |= SND_BRK;
else
clear_bits |= SND_BRK;
spin_lock_irqsave(&port->lock, flags);
new_reg = (uap->curregs[R5] | set_bits) & ~clear_bits;
if (new_reg != uap->curregs[R5]) {
uap->curregs[R5] = new_reg;
/* NOTE: Not subject to 'transmitter active' rule. */
if (ZS_IS_ASLEEP(uap))
return;
write_zsreg(uap, R5, uap->curregs[R5]);
}
spin_unlock_irqrestore(&port->lock, flags);
}
/*
* Turn power on or off to the SCC and associated stuff
* (port drivers, modem, IR port, etc.)
* Returns the number of milliseconds we should wait before
* trying to use the port.
*/
static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
{
int delay = 0;
int rc;
if (state) {
rc = pmac_call_feature(
PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 1);
pmz_debug("port power on result: %d\n", rc);
if (ZS_IS_INTMODEM(uap)) {
rc = pmac_call_feature(
PMAC_FTR_MODEM_ENABLE, uap->node, 0, 1);
delay = 2500; /* wait for 2.5s before using */
pmz_debug("modem power result: %d\n", rc);
}
} else {
/* TODO: Make that depend on a timer, don't power down
* immediately
*/
if (ZS_IS_INTMODEM(uap)) {
rc = pmac_call_feature(
PMAC_FTR_MODEM_ENABLE, uap->node, 0, 0);
pmz_debug("port power off result: %d\n", rc);
}
pmac_call_feature(PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 0);
}
return delay;
}
/*
* FixZeroBug....Works around a bug in the SCC receving channel.
* Inspired from Darwin code, 15 Sept. 2000 -DanM
*
* The following sequence prevents a problem that is seen with O'Hare ASICs
* (most versions -- also with some Heathrow and Hydra ASICs) where a zero
* at the input to the receiver becomes 'stuck' and locks up the receiver.
* This problem can occur as a result of a zero bit at the receiver input
* coincident with any of the following events:
*
* The SCC is initialized (hardware or software).
* A framing error is detected.
* The clocking option changes from synchronous or X1 asynchronous
* clocking to X16, X32, or X64 asynchronous clocking.
* The decoding mode is changed among NRZ, NRZI, FM0, or FM1.
*
* This workaround attempts to recover from the lockup condition by placing
* the SCC in synchronous loopback mode with a fast clock before programming
* any of the asynchronous modes.
*/
static void pmz_fix_zero_bug_scc(struct uart_pmac_port *uap)
{
write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
zssync(uap);
udelay(10);
write_zsreg(uap, 9, (ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB) | NV);
zssync(uap);
write_zsreg(uap, 4, X1CLK | MONSYNC);
write_zsreg(uap, 3, Rx8);
write_zsreg(uap, 5, Tx8 | RTS);
write_zsreg(uap, 9, NV); /* Didn't we already do this? */
write_zsreg(uap, 11, RCBR | TCBR);
write_zsreg(uap, 12, 0);
write_zsreg(uap, 13, 0);
write_zsreg(uap, 14, (LOOPBAK | BRSRC));
write_zsreg(uap, 14, (LOOPBAK | BRSRC | BRENAB));
write_zsreg(uap, 3, Rx8 | RxENABLE);
write_zsreg(uap, 0, RES_EXT_INT);
write_zsreg(uap, 0, RES_EXT_INT);
write_zsreg(uap, 0, RES_EXT_INT); /* to kill some time */
/* The channel should be OK now, but it is probably receiving
* loopback garbage.
* Switch to asynchronous mode, disable the receiver,
* and discard everything in the receive buffer.
*/
write_zsreg(uap, 9, NV);
write_zsreg(uap, 4, X16CLK | SB_MASK);
write_zsreg(uap, 3, Rx8);
while (read_zsreg(uap, 0) & Rx_CH_AV) {
(void)read_zsreg(uap, 8);
write_zsreg(uap, 0, RES_EXT_INT);
write_zsreg(uap, 0, ERR_RES);
}
}
/*
* Real startup routine, powers up the hardware and sets up
* the SCC. Returns a delay in ms where you need to wait before
* actually using the port, this is typically the internal modem
* powerup delay. This routine expect the lock to be taken.
*/
static int __pmz_startup(struct uart_pmac_port *uap)
{
int pwr_delay = 0;
memset(&uap->curregs, 0, sizeof(uap->curregs));
/* Power up the SCC & underlying hardware (modem/irda) */
pwr_delay = pmz_set_scc_power(uap, 1);
/* Nice buggy HW ... */
pmz_fix_zero_bug_scc(uap);
/* Reset the channel */
uap->curregs[R9] = 0;
write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
zssync(uap);
udelay(10);
write_zsreg(uap, 9, 0);
zssync(uap);
/* Clear the interrupt registers */
write_zsreg(uap, R1, 0);
write_zsreg(uap, R0, ERR_RES);
write_zsreg(uap, R0, ERR_RES);
write_zsreg(uap, R0, RES_H_IUS);
write_zsreg(uap, R0, RES_H_IUS);
/* Setup some valid baud rate */
uap->curregs[R4] = X16CLK | SB1;
uap->curregs[R3] = Rx8;
uap->curregs[R5] = Tx8 | RTS;
if (!ZS_IS_IRDA(uap))
uap->curregs[R5] |= DTR;
uap->curregs[R12] = 0;
uap->curregs[R13] = 0;
uap->curregs[R14] = BRENAB;
/* Clear handshaking, enable BREAK interrupts */
uap->curregs[R15] = BRKIE;
/* Master interrupt enable */
uap->curregs[R9] |= NV | MIE;
pmz_load_zsregs(uap, uap->curregs);
/* Enable receiver and transmitter. */
write_zsreg(uap, R3, uap->curregs[R3] |= RxENABLE);
write_zsreg(uap, R5, uap->curregs[R5] |= TxENABLE);
/* Remember status for DCD/CTS changes */
uap->prev_status = read_zsreg(uap, R0);
return pwr_delay;
}
static void pmz_irda_reset(struct uart_pmac_port *uap)
{
uap->curregs[R5] |= DTR;
write_zsreg(uap, R5, uap->curregs[R5]);
zssync(uap);
mdelay(110);
uap->curregs[R5] &= ~DTR;
write_zsreg(uap, R5, uap->curregs[R5]);
zssync(uap);
mdelay(10);
}
/*
* This is the "normal" startup routine, using the above one
* wrapped with the lock and doing a schedule delay
*/
static int pmz_startup(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned long flags;
int pwr_delay = 0;
pmz_debug("pmz: startup()\n");
if (ZS_IS_ASLEEP(uap))
return -EAGAIN;
if (uap->node == NULL)
return -ENODEV;
down(&pmz_irq_sem);
uap->flags |= PMACZILOG_FLAG_IS_OPEN;
/* A console is never powered down. Else, power up and
* initialize the chip
*/
if (!ZS_IS_CONS(uap)) {
spin_lock_irqsave(&port->lock, flags);
pwr_delay = __pmz_startup(uap);
spin_unlock_irqrestore(&port->lock, flags);
}
pmz_get_port_A(uap)->flags |= PMACZILOG_FLAG_IS_IRQ_ON;
if (request_irq(uap->port.irq, pmz_interrupt, SA_SHIRQ, "PowerMac Zilog", uap)) {
dev_err(&uap->dev->ofdev.dev,
"Unable to register zs interrupt handler.\n");
pmz_set_scc_power(uap, 0);
up(&pmz_irq_sem);
return -ENXIO;
}
up(&pmz_irq_sem);
/* Right now, we deal with delay by blocking here, I'll be
* smarter later on
*/
if (pwr_delay != 0) {
pmz_debug("pmz: delaying %d ms\n", pwr_delay);
msleep(pwr_delay);
}
/* IrDA reset is done now */
if (ZS_IS_IRDA(uap))
pmz_irda_reset(uap);
/* Enable interrupts emission from the chip */
spin_lock_irqsave(&port->lock, flags);
uap->curregs[R1] |= INT_ALL_Rx | TxINT_ENAB;
if (!ZS_IS_EXTCLK(uap))
uap->curregs[R1] |= EXT_INT_ENAB;
write_zsreg(uap, R1, uap->curregs[R1]);
spin_unlock_irqrestore(&port->lock, flags);
pmz_debug("pmz: startup() done.\n");
return 0;
}
static void pmz_shutdown(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned long flags;
pmz_debug("pmz: shutdown()\n");
if (uap->node == NULL)
return;
down(&pmz_irq_sem);
/* Release interrupt handler */
free_irq(uap->port.irq, uap);
spin_lock_irqsave(&port->lock, flags);
uap->flags &= ~PMACZILOG_FLAG_IS_OPEN;
if (!ZS_IS_OPEN(uap->mate))
pmz_get_port_A(uap)->flags &= ~PMACZILOG_FLAG_IS_IRQ_ON;
/* Disable interrupts */
if (!ZS_IS_ASLEEP(uap)) {
uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
write_zsreg(uap, R1, uap->curregs[R1]);
zssync(uap);
}
if (ZS_IS_CONS(uap) || ZS_IS_ASLEEP(uap)) {
spin_unlock_irqrestore(&port->lock, flags);
up(&pmz_irq_sem);
return;
}
/* Disable receiver and transmitter. */
uap->curregs[R3] &= ~RxENABLE;
uap->curregs[R5] &= ~TxENABLE;
/* Disable all interrupts and BRK assertion. */
uap->curregs[R5] &= ~SND_BRK;
pmz_maybe_update_regs(uap);
/* Shut the chip down */
pmz_set_scc_power(uap, 0);
spin_unlock_irqrestore(&port->lock, flags);
up(&pmz_irq_sem);
pmz_debug("pmz: shutdown() done.\n");
}
/* Shared by TTY driver and serial console setup. The port lock is held
* and local interrupts are disabled.
*/
static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,
unsigned int iflag, unsigned long baud)
{
int brg;
/* Switch to external clocking for IrDA high clock rates. That
* code could be re-used for Midi interfaces with different
* multipliers
*/
if (baud >= 115200 && ZS_IS_IRDA(uap)) {
uap->curregs[R4] = X1CLK;
uap->curregs[R11] = RCTRxCP | TCTRxCP;
uap->curregs[R14] = 0; /* BRG off */
uap->curregs[R12] = 0;
uap->curregs[R13] = 0;
uap->flags |= PMACZILOG_FLAG_IS_EXTCLK;
} else {
switch (baud) {
case ZS_CLOCK/16: /* 230400 */
uap->curregs[R4] = X16CLK;
uap->curregs[R11] = 0;
uap->curregs[R14] = 0;
break;
case ZS_CLOCK/32: /* 115200 */
uap->curregs[R4] = X32CLK;
uap->curregs[R11] = 0;
uap->curregs[R14] = 0;
break;
default:
uap->curregs[R4] = X16CLK;
uap->curregs[R11] = TCBR | RCBR;
brg = BPS_TO_BRG(baud, ZS_CLOCK / 16);
uap->curregs[R12] = (brg & 255);
uap->curregs[R13] = ((brg >> 8) & 255);
uap->curregs[R14] = BRENAB;
}
uap->flags &= ~PMACZILOG_FLAG_IS_EXTCLK;
}
/* Character size, stop bits, and parity. */
uap->curregs[3] &= ~RxN_MASK;
uap->curregs[5] &= ~TxN_MASK;
switch (cflag & CSIZE) {
case CS5:
uap->curregs[3] |= Rx5;
uap->curregs[5] |= Tx5;
uap->parity_mask = 0x1f;
break;
case CS6:
uap->curregs[3] |= Rx6;
uap->curregs[5] |= Tx6;
uap->parity_mask = 0x3f;
break;
case CS7:
uap->curregs[3] |= Rx7;
uap->curregs[5] |= Tx7;
uap->parity_mask = 0x7f;
break;
case CS8:
default:
uap->curregs[3] |= Rx8;
uap->curregs[5] |= Tx8;
uap->parity_mask = 0xff;
break;
};
uap->curregs[4] &= ~(SB_MASK);
if (cflag & CSTOPB)
uap->curregs[4] |= SB2;
else
uap->curregs[4] |= SB1;
if (cflag & PARENB)
uap->curregs[4] |= PAR_ENAB;
else
uap->curregs[4] &= ~PAR_ENAB;
if (!(cflag & PARODD))
uap->curregs[4] |= PAR_EVEN;
else
uap->curregs[4] &= ~PAR_EVEN;
uap->port.read_status_mask = Rx_OVR;
if (iflag & INPCK)
uap->port.read_status_mask |= CRC_ERR | PAR_ERR;
if (iflag & (BRKINT | PARMRK))
uap->port.read_status_mask |= BRK_ABRT;
uap->port.ignore_status_mask = 0;
if (iflag & IGNPAR)
uap->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
if (iflag & IGNBRK) {
uap->port.ignore_status_mask |= BRK_ABRT;
if (iflag & IGNPAR)
uap->port.ignore_status_mask |= Rx_OVR;
}
if ((cflag & CREAD) == 0)
uap->port.ignore_status_mask = 0xff;
}
/*
* Set the irda codec on the imac to the specified baud rate.
*/
static void pmz_irda_setup(struct uart_pmac_port *uap, unsigned long *baud)
{
u8 cmdbyte;
int t, version;
switch (*baud) {
/* SIR modes */
case 2400:
cmdbyte = 0x53;
break;
case 4800:
cmdbyte = 0x52;
break;
case 9600:
cmdbyte = 0x51;
break;
case 19200:
cmdbyte = 0x50;
break;
case 38400:
cmdbyte = 0x4f;
break;
case 57600:
cmdbyte = 0x4e;
break;
case 115200:
cmdbyte = 0x4d;
break;
/* The FIR modes aren't really supported at this point, how
* do we select the speed ? via the FCR on KeyLargo ?
*/
case 1152000:
cmdbyte = 0;
break;
case 4000000:
cmdbyte = 0;
break;
default: /* 9600 */
cmdbyte = 0x51;
*baud = 9600;
break;
}
/* Wait for transmitter to drain */
t = 10000;
while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0
|| (read_zsreg(uap, R1) & ALL_SNT) == 0) {
if (--t <= 0) {
dev_err(&uap->dev->ofdev.dev, "transmitter didn't drain\n");
return;
}
udelay(10);
}
/* Drain the receiver too */
t = 100;
(void)read_zsdata(uap);
(void)read_zsdata(uap);
(void)read_zsdata(uap);
mdelay(10);
while (read_zsreg(uap, R0) & Rx_CH_AV) {
read_zsdata(uap);
mdelay(10);
if (--t <= 0) {
dev_err(&uap->dev->ofdev.dev, "receiver didn't drain\n");
return;
}
}
/* Switch to command mode */
uap->curregs[R5] |= DTR;
write_zsreg(uap, R5, uap->curregs[R5]);
zssync(uap);
mdelay(1);
/* Switch SCC to 19200 */
pmz_convert_to_zs(uap, CS8, 0, 19200);
pmz_load_zsregs(uap, uap->curregs);
mdelay(1);
/* Write get_version command byte */
write_zsdata(uap, 1);
t = 5000;
while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
if (--t <= 0) {
dev_err(&uap->dev->ofdev.dev,
"irda_setup timed out on get_version byte\n");
goto out;
}
udelay(10);
}
version = read_zsdata(uap);
if (version < 4) {
dev_info(&uap->dev->ofdev.dev, "IrDA: dongle version %d not supported\n",
version);
goto out;
}
/* Send speed mode */
write_zsdata(uap, cmdbyte);
t = 5000;
while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
if (--t <= 0) {
dev_err(&uap->dev->ofdev.dev,
"irda_setup timed out on speed mode byte\n");
goto out;
}
udelay(10);
}
t = read_zsdata(uap);
if (t != cmdbyte)
dev_err(&uap->dev->ofdev.dev,
"irda_setup speed mode byte = %x (%x)\n", t, cmdbyte);
dev_info(&uap->dev->ofdev.dev, "IrDA setup for %ld bps, dongle version: %d\n",
*baud, version);
(void)read_zsdata(uap);
(void)read_zsdata(uap);
(void)read_zsdata(uap);
out:
/* Switch back to data mode */
uap->curregs[R5] &= ~DTR;
write_zsreg(uap, R5, uap->curregs[R5]);
zssync(uap);
(void)read_zsdata(uap);
(void)read_zsdata(uap);
(void)read_zsdata(uap);
}
static void __pmz_set_termios(struct uart_port *port, struct termios *termios,
struct termios *old)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned long baud;
pmz_debug("pmz: set_termios()\n");
if (ZS_IS_ASLEEP(uap))
return;
memcpy(&uap->termios_cache, termios, sizeof(struct termios));
/* XXX Check which revs of machines actually allow 1 and 4Mb speeds
* on the IR dongle. Note that the IRTTY driver currently doesn't know
* about the FIR mode and high speed modes. So these are unused. For
* implementing proper support for these, we should probably add some
* DMA as well, at least on the Rx side, which isn't a simple thing
* at this point.
*/
if (ZS_IS_IRDA(uap)) {
/* Calc baud rate */
baud = uart_get_baud_rate(port, termios, old, 1200, 4000000);
pmz_debug("pmz: switch IRDA to %ld bauds\n", baud);
/* Cet the irda codec to the right rate */
pmz_irda_setup(uap, &baud);
/* Set final baud rate */
pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
pmz_load_zsregs(uap, uap->curregs);
zssync(uap);
} else {
baud = uart_get_baud_rate(port, termios, old, 1200, 230400);
pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
/* Make sure modem status interrupts are correctly configured */
if (UART_ENABLE_MS(&uap->port, termios->c_cflag)) {
uap->curregs[R15] |= DCDIE | SYNCIE | CTSIE;
uap->flags |= PMACZILOG_FLAG_MODEM_STATUS;
} else {
uap->curregs[R15] &= ~(DCDIE | SYNCIE | CTSIE);
uap->flags &= ~PMACZILOG_FLAG_MODEM_STATUS;
}
/* Load registers to the chip */
pmz_maybe_update_regs(uap);
}
uart_update_timeout(port, termios->c_cflag, baud);
pmz_debug("pmz: set_termios() done.\n");
}
/* The port lock is not held. */
static void pmz_set_termios(struct uart_port *port, struct termios *termios,
struct termios *old)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
/* Disable IRQs on the port */
uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
write_zsreg(uap, R1, uap->curregs[R1]);
/* Setup new port configuration */
__pmz_set_termios(port, termios, old);
/* Re-enable IRQs on the port */
if (ZS_IS_OPEN(uap)) {
uap->curregs[R1] |= INT_ALL_Rx | TxINT_ENAB;
if (!ZS_IS_EXTCLK(uap))
uap->curregs[R1] |= EXT_INT_ENAB;
write_zsreg(uap, R1, uap->curregs[R1]);
}
spin_unlock_irqrestore(&port->lock, flags);
}
static const char *pmz_type(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
if (ZS_IS_IRDA(uap))
return "Z85c30 ESCC - Infrared port";
else if (ZS_IS_INTMODEM(uap))
return "Z85c30 ESCC - Internal modem";
return "Z85c30 ESCC - Serial port";
}
/* We do not request/release mappings of the registers here, this
* happens at early serial probe time.
*/
static void pmz_release_port(struct uart_port *port)
{
}
static int pmz_request_port(struct uart_port *port)
{
return 0;
}
/* These do not need to do anything interesting either. */
static void pmz_config_port(struct uart_port *port, int flags)
{
}
/* We do not support letting the user mess with the divisor, IRQ, etc. */
static int pmz_verify_port(struct uart_port *port, struct serial_struct *ser)
{
return -EINVAL;
}
static struct uart_ops pmz_pops = {
.tx_empty = pmz_tx_empty,
.set_mctrl = pmz_set_mctrl,
.get_mctrl = pmz_get_mctrl,
.stop_tx = pmz_stop_tx,
.start_tx = pmz_start_tx,
.stop_rx = pmz_stop_rx,
.enable_ms = pmz_enable_ms,
.break_ctl = pmz_break_ctl,
.startup = pmz_startup,
.shutdown = pmz_shutdown,
.set_termios = pmz_set_termios,
.type = pmz_type,
.release_port = pmz_release_port,
.request_port = pmz_request_port,
.config_port = pmz_config_port,
.verify_port = pmz_verify_port,
};
/*
* Setup one port structure after probing, HW is down at this point,
* Unlike sunzilog, we don't need to pre-init the spinlock as we don't
* register our console before uart_add_one_port() is called
*/
static int __init pmz_init_port(struct uart_pmac_port *uap)
{
struct device_node *np = uap->node;
char *conn;
struct slot_names_prop {
int count;
char name[1];
} *slots;
int len;
/*
* Request & map chip registers
*/
uap->port.mapbase = np->addrs[0].address;
uap->port.membase = ioremap(uap->port.mapbase, 0x1000);
uap->control_reg = uap->port.membase;
uap->data_reg = uap->control_reg + 0x10;
/*
* Request & map DBDMA registers
*/
#ifdef HAS_DBDMA
if (np->n_addrs >= 3 && np->n_intrs >= 3)
uap->flags |= PMACZILOG_FLAG_HAS_DMA;
#endif
if (ZS_HAS_DMA(uap)) {
uap->tx_dma_regs = ioremap(np->addrs[np->n_addrs - 2].address, 0x1000);
if (uap->tx_dma_regs == NULL) {
uap->flags &= ~PMACZILOG_FLAG_HAS_DMA;
goto no_dma;
}
uap->rx_dma_regs = ioremap(np->addrs[np->n_addrs - 1].address, 0x1000);
if (uap->rx_dma_regs == NULL) {
iounmap(uap->tx_dma_regs);
uap->tx_dma_regs = NULL;
uap->flags &= ~PMACZILOG_FLAG_HAS_DMA;
goto no_dma;
}
uap->tx_dma_irq = np->intrs[1].line;
uap->rx_dma_irq = np->intrs[2].line;
}
no_dma:
/*
* Detect port type
*/
if (device_is_compatible(np, "cobalt"))
uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
conn = get_property(np, "AAPL,connector", &len);
if (conn && (strcmp(conn, "infrared") == 0))
uap->flags |= PMACZILOG_FLAG_IS_IRDA;
uap->port_type = PMAC_SCC_ASYNC;
/* 1999 Powerbook G3 has slot-names property instead */
slots = (struct slot_names_prop *)get_property(np, "slot-names", &len);
if (slots && slots->count > 0) {
if (strcmp(slots->name, "IrDA") == 0)
uap->flags |= PMACZILOG_FLAG_IS_IRDA;
else if (strcmp(slots->name, "Modem") == 0)
uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
}
if (ZS_IS_IRDA(uap))
uap->port_type = PMAC_SCC_IRDA;
if (ZS_IS_INTMODEM(uap)) {
struct device_node* i2c_modem = find_devices("i2c-modem");
if (i2c_modem) {
char* mid = get_property(i2c_modem, "modem-id", NULL);
if (mid) switch(*mid) {
case 0x04 :
case 0x05 :
case 0x07 :
case 0x08 :
case 0x0b :
case 0x0c :
uap->port_type = PMAC_SCC_I2S1;
}
printk(KERN_INFO "pmac_zilog: i2c-modem detected, id: %d\n",
mid ? (*mid) : 0);
} else {
printk(KERN_INFO "pmac_zilog: serial modem detected\n");
}
}
/*
* Init remaining bits of "port" structure
*/
uap->port.iotype = SERIAL_IO_MEM;
uap->port.irq = np->intrs[0].line;
uap->port.uartclk = ZS_CLOCK;
uap->port.fifosize = 1;
uap->port.ops = &pmz_pops;
uap->port.type = PORT_PMAC_ZILOG;
uap->port.flags = 0;
/* Setup some valid baud rate information in the register
* shadows so we don't write crap there before baud rate is
* first initialized.
*/
pmz_convert_to_zs(uap, CS8, 0, 9600);
return 0;
}
/*
* Get rid of a port on module removal
*/
static void pmz_dispose_port(struct uart_pmac_port *uap)
{
struct device_node *np;
np = uap->node;
iounmap(uap->rx_dma_regs);
iounmap(uap->tx_dma_regs);
iounmap(uap->control_reg);
uap->node = NULL;
of_node_put(np);
memset(uap, 0, sizeof(struct uart_pmac_port));
}
/*
* Called upon match with an escc node in the devive-tree.
*/
static int pmz_attach(struct macio_dev *mdev, const struct of_device_id *match)
{
int i;
/* Iterate the pmz_ports array to find a matching entry
*/
for (i = 0; i < MAX_ZS_PORTS; i++)
if (pmz_ports[i].node == mdev->ofdev.node) {
struct uart_pmac_port *uap = &pmz_ports[i];
uap->dev = mdev;
dev_set_drvdata(&mdev->ofdev.dev, uap);
if (macio_request_resources(uap->dev, "pmac_zilog"))
printk(KERN_WARNING "%s: Failed to request resource"
", port still active\n",
uap->node->name);
else
uap->flags |= PMACZILOG_FLAG_RSRC_REQUESTED;
return 0;
}
return -ENODEV;
}
/*
* That one should not be called, macio isn't really a hotswap device,
* we don't expect one of those serial ports to go away...
*/
static int pmz_detach(struct macio_dev *mdev)
{
struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
if (!uap)
return -ENODEV;
if (uap->flags & PMACZILOG_FLAG_RSRC_REQUESTED) {
macio_release_resources(uap->dev);
uap->flags &= ~PMACZILOG_FLAG_RSRC_REQUESTED;
}
dev_set_drvdata(&mdev->ofdev.dev, NULL);
uap->dev = NULL;
return 0;
}
static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
{
struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
struct uart_state *state;
unsigned long flags;
if (uap == NULL) {
printk("HRM... pmz_suspend with NULL uap\n");
return 0;
}
if (pm_state == mdev->ofdev.dev.power.power_state || pm_state < 2)
return 0;
pmz_debug("suspend, switching to state %d\n", pm_state);
state = pmz_uart_reg.state + uap->port.line;
down(&pmz_irq_sem);
down(&state->sem);
spin_lock_irqsave(&uap->port.lock, flags);
if (ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)) {
/* Disable receiver and transmitter. */
uap->curregs[R3] &= ~RxENABLE;
uap->curregs[R5] &= ~TxENABLE;
/* Disable all interrupts and BRK assertion. */
uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
uap->curregs[R5] &= ~SND_BRK;
pmz_load_zsregs(uap, uap->curregs);
uap->flags |= PMACZILOG_FLAG_IS_ASLEEP;
mb();
}
spin_unlock_irqrestore(&uap->port.lock, flags);
if (ZS_IS_OPEN(uap) || ZS_IS_OPEN(uap->mate))
if (ZS_IS_ASLEEP(uap->mate) && ZS_IS_IRQ_ON(pmz_get_port_A(uap))) {
pmz_get_port_A(uap)->flags &= ~PMACZILOG_FLAG_IS_IRQ_ON;
disable_irq(uap->port.irq);
}
if (ZS_IS_CONS(uap))
uap->port.cons->flags &= ~CON_ENABLED;
/* Shut the chip down */
pmz_set_scc_power(uap, 0);
up(&state->sem);
up(&pmz_irq_sem);
pmz_debug("suspend, switching complete\n");
mdev->ofdev.dev.power.power_state = pm_state;
return 0;
}
static int pmz_resume(struct macio_dev *mdev)
{
struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
struct uart_state *state;
unsigned long flags;
int pwr_delay = 0;
if (uap == NULL)
return 0;
if (mdev->ofdev.dev.power.power_state == 0)
return 0;
pmz_debug("resume, switching to state 0\n");
state = pmz_uart_reg.state + uap->port.line;
down(&pmz_irq_sem);
down(&state->sem);
spin_lock_irqsave(&uap->port.lock, flags);
if (!ZS_IS_OPEN(uap) && !ZS_IS_CONS(uap)) {
spin_unlock_irqrestore(&uap->port.lock, flags);
goto bail;
}
pwr_delay = __pmz_startup(uap);
/* Take care of config that may have changed while asleep */
__pmz_set_termios(&uap->port, &uap->termios_cache, NULL);
if (ZS_IS_OPEN(uap)) {
/* Enable interrupts */
uap->curregs[R1] |= INT_ALL_Rx | TxINT_ENAB;
if (!ZS_IS_EXTCLK(uap))
uap->curregs[R1] |= EXT_INT_ENAB;
write_zsreg(uap, R1, uap->curregs[R1]);
}
spin_unlock_irqrestore(&uap->port.lock, flags);
if (ZS_IS_CONS(uap))
uap->port.cons->flags |= CON_ENABLED;
/* Re-enable IRQ on the controller */
if (ZS_IS_OPEN(uap) && !ZS_IS_IRQ_ON(pmz_get_port_A(uap))) {
pmz_get_port_A(uap)->flags |= PMACZILOG_FLAG_IS_IRQ_ON;
enable_irq(uap->port.irq);
}
bail:
up(&state->sem);
up(&pmz_irq_sem);
/* Right now, we deal with delay by blocking here, I'll be
* smarter later on
*/
if (pwr_delay != 0) {
pmz_debug("pmz: delaying %d ms\n", pwr_delay);
msleep(pwr_delay);
}
pmz_debug("resume, switching complete\n");
mdev->ofdev.dev.power.power_state = 0;
return 0;
}
/*
* Probe all ports in the system and build the ports array, we register
* with the serial layer at this point, the macio-type probing is only
* used later to "attach" to the sysfs tree so we get power management
* events
*/
static int __init pmz_probe(void)
{
struct device_node *node_p, *node_a, *node_b, *np;
int count = 0;
int rc;
/*
* Find all escc chips in the system
*/
node_p = of_find_node_by_name(NULL, "escc");
while (node_p) {
/*
* First get channel A/B node pointers
*
* TODO: Add routines with proper locking to do that...
*/
node_a = node_b = NULL;
for (np = NULL; (np = of_get_next_child(node_p, np)) != NULL;) {
if (strncmp(np->name, "ch-a", 4) == 0)
node_a = of_node_get(np);
else if (strncmp(np->name, "ch-b", 4) == 0)
node_b = of_node_get(np);
}
if (!node_a && !node_b) {
of_node_put(node_a);
of_node_put(node_b);
printk(KERN_ERR "pmac_zilog: missing node %c for escc %s\n",
(!node_a) ? 'a' : 'b', node_p->full_name);
goto next;
}
/*
* Fill basic fields in the port structures
*/
pmz_ports[count].mate = &pmz_ports[count+1];
pmz_ports[count+1].mate = &pmz_ports[count];
pmz_ports[count].flags = PMACZILOG_FLAG_IS_CHANNEL_A;
pmz_ports[count].node = node_a;
pmz_ports[count+1].node = node_b;
pmz_ports[count].port.line = count;
pmz_ports[count+1].port.line = count+1;
/*
* Setup the ports for real
*/
rc = pmz_init_port(&pmz_ports[count]);
if (rc == 0 && node_b != NULL)
rc = pmz_init_port(&pmz_ports[count+1]);
if (rc != 0) {
of_node_put(node_a);
of_node_put(node_b);
memset(&pmz_ports[count], 0, sizeof(struct uart_pmac_port));
memset(&pmz_ports[count+1], 0, sizeof(struct uart_pmac_port));
goto next;
}
count += 2;
next:
node_p = of_find_node_by_name(node_p, "escc");
}
pmz_ports_count = count;
return 0;
}
#ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
static void pmz_console_write(struct console *con, const char *s, unsigned int count);
static int __init pmz_console_setup(struct console *co, char *options);
static struct console pmz_console = {
.name = "ttyS",
.write = pmz_console_write,
.device = uart_console_device,
.setup = pmz_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &pmz_uart_reg,
};
#define PMACZILOG_CONSOLE &pmz_console
#else /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
#define PMACZILOG_CONSOLE (NULL)
#endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
/*
* Register the driver, console driver and ports with the serial
* core
*/
static int __init pmz_register(void)
{
int i, rc;
pmz_uart_reg.nr = pmz_ports_count;
pmz_uart_reg.cons = PMACZILOG_CONSOLE;
pmz_uart_reg.minor = 64;
/*
* Register this driver with the serial core
*/
rc = uart_register_driver(&pmz_uart_reg);
if (rc)
return rc;
/*
* Register each port with the serial core
*/
for (i = 0; i < pmz_ports_count; i++) {
struct uart_pmac_port *uport = &pmz_ports[i];
/* NULL node may happen on wallstreet */
if (uport->node != NULL)
rc = uart_add_one_port(&pmz_uart_reg, &uport->port);
if (rc)
goto err_out;
}
return 0;
err_out:
while (i-- > 0) {
struct uart_pmac_port *uport = &pmz_ports[i];
uart_remove_one_port(&pmz_uart_reg, &uport->port);
}
uart_unregister_driver(&pmz_uart_reg);
return rc;
}
static struct of_device_id pmz_match[] =
{
{
.name = "ch-a",
},
{
.name = "ch-b",
},
{},
};
MODULE_DEVICE_TABLE (of, pmz_match);
static struct macio_driver pmz_driver =
{
.name = "pmac_zilog",
.match_table = pmz_match,
.probe = pmz_attach,
.remove = pmz_detach,
.suspend = pmz_suspend,
.resume = pmz_resume,
};
static int __init init_pmz(void)
{
int rc, i;
printk(KERN_INFO "%s\n", version);
/*
* First, we need to do a direct OF-based probe pass. We
* do that because we want serial console up before the
* macio stuffs calls us back, and since that makes it
* easier to pass the proper number of channels to
* uart_register_driver()
*/
if (pmz_ports_count == 0)
pmz_probe();
/*
* Bail early if no port found
*/
if (pmz_ports_count == 0)
return -ENODEV;
/*
* Now we register with the serial layer
*/
rc = pmz_register();
if (rc) {
printk(KERN_ERR
"pmac_zilog: Error registering serial device, disabling pmac_zilog.\n"
"pmac_zilog: Did another serial driver already claim the minors?\n");
/* effectively "pmz_unprobe()" */
for (i=0; i < pmz_ports_count; i++)
pmz_dispose_port(&pmz_ports[i]);
return rc;
}
/*
* Then we register the macio driver itself
*/
return macio_register_driver(&pmz_driver);
}
static void __exit exit_pmz(void)
{
int i;
/* Get rid of macio-driver (detach from macio) */
macio_unregister_driver(&pmz_driver);
for (i = 0; i < pmz_ports_count; i++) {
struct uart_pmac_port *uport = &pmz_ports[i];
if (uport->node != NULL) {
uart_remove_one_port(&pmz_uart_reg, &uport->port);
pmz_dispose_port(uport);
}
}
/* Unregister UART driver */
uart_unregister_driver(&pmz_uart_reg);
}
#ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
/*
* Print a string to the serial port trying not to disturb
* any possible real use of the port...
*/
static void pmz_console_write(struct console *con, const char *s, unsigned int count)
{
struct uart_pmac_port *uap = &pmz_ports[con->index];
unsigned long flags;
int i;
if (ZS_IS_ASLEEP(uap))
return;
spin_lock_irqsave(&uap->port.lock, flags);
/* Turn of interrupts and enable the transmitter. */
write_zsreg(uap, R1, uap->curregs[1] & ~TxINT_ENAB);
write_zsreg(uap, R5, uap->curregs[5] | TxENABLE | RTS | DTR);
for (i = 0; i < count; i++) {
/* Wait for the transmit buffer to empty. */
while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
udelay(5);
write_zsdata(uap, s[i]);
if (s[i] == 10) {
while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
udelay(5);
write_zsdata(uap, R13);
}
}
/* Restore the values in the registers. */
write_zsreg(uap, R1, uap->curregs[1]);
/* Don't disable the transmitter. */
spin_unlock_irqrestore(&uap->port.lock, flags);
}
/*
* Setup the serial console
*/
static int __init pmz_console_setup(struct console *co, char *options)
{
struct uart_pmac_port *uap;
struct uart_port *port;
int baud = 38400;
int bits = 8;
int parity = 'n';
int flow = 'n';
unsigned long pwr_delay;
/*
* XServe's default to 57600 bps
*/
if (machine_is_compatible("RackMac1,1")
|| machine_is_compatible("RackMac1,2")
|| machine_is_compatible("MacRISC4"))
baud = 57600;
/*
* 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 >= pmz_ports_count)
co->index = 0;
uap = &pmz_ports[co->index];
if (uap->node == NULL)
return -ENODEV;
port = &uap->port;
/*
* Mark port as beeing a console
*/
uap->flags |= PMACZILOG_FLAG_IS_CONS;
/*
* Temporary fix for uart layer who didn't setup the spinlock yet
*/
spin_lock_init(&port->lock);
/*
* Enable the hardware
*/
pwr_delay = __pmz_startup(uap);
if (pwr_delay)
mdelay(pwr_delay);
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
return uart_set_options(port, co, baud, parity, bits, flow);
}
static int __init pmz_console_init(void)
{
/* Probe ports */
pmz_probe();
/* TODO: Autoprobe console based on OF */
/* pmz_console.index = i; */
register_console(&pmz_console);
return 0;
}
console_initcall(pmz_console_init);
#endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
module_init(init_pmz);
module_exit(exit_pmz);
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