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authorMaciej W. Rozycki <macro@linux-mips.org>2006-12-06 20:38:59 -0800
committerLinus Torvalds <torvalds@woody.osdl.org>2006-12-07 08:39:41 -0800
commit9399575dd30edcb84e821583daf81d4ba774a95b (patch)
tree0dbd1b3607277dfb67ecffaf5a35197d08a8b563 /drivers/serial/dz.c
parentf7dff2b12654149c9cac8d8c79b6588759edd5a9 (diff)
[PATCH] dz: Fixes to make it work
This a set of fixes mostly to make the driver actually work: 1. Actually select the line for setting parameters and receiver disable/enable. 2. Select the line for receive and transmit interrupt handling correctly. 3. Report the transmitter empty state correctly. 4. Set the I/O type of ports correctly. 5. Perform polled transmission correctly. 6. Don't fix the console line at ttyS3. 7. Magic SysRq support. 8. Various small bits here and there. Tested with a DECstation 2100 (thanks Flo for making this possible). [akpm@osdl.org: fix typo] Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/serial/dz.c')
-rw-r--r--drivers/serial/dz.c371
1 files changed, 186 insertions, 185 deletions
diff --git a/drivers/serial/dz.c b/drivers/serial/dz.c
index 53662b33b841..af1544f3356f 100644
--- a/drivers/serial/dz.c
+++ b/drivers/serial/dz.c
@@ -1,11 +1,13 @@
/*
- * dz.c: Serial port driver for DECStations equiped
+ * dz.c: Serial port driver for DECstations equipped
* with the DZ chipset.
*
* Copyright (C) 1998 Olivier A. D. Lebaillif
*
* Email: olivier.lebaillif@ifrsys.com
*
+ * Copyright (C) 2004, 2006 Maciej W. Rozycki
+ *
* [31-AUG-98] triemer
* Changed IRQ to use Harald's dec internals interrupts.h
* removed base_addr code - moving address assignment to setup.c
@@ -26,10 +28,16 @@
#undef DEBUG_DZ
+#if defined(CONFIG_SERIAL_DZ_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/delay.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/console.h>
+#include <linux/sysrq.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
@@ -45,14 +53,10 @@
#include <asm/system.h>
#include <asm/uaccess.h>
-#define CONSOLE_LINE (3) /* for definition of struct console */
-
#include "dz.h"
-#define DZ_INTR_DEBUG 1
-
static char *dz_name = "DECstation DZ serial driver version ";
-static char *dz_version = "1.02";
+static char *dz_version = "1.03";
struct dz_port {
struct uart_port port;
@@ -61,22 +65,6 @@ struct dz_port {
static struct dz_port dz_ports[DZ_NB_PORT];
-#ifdef DEBUG_DZ
-/*
- * debugging code to send out chars via prom
- */
-static void debug_console(const char *s, int count)
-{
- unsigned i;
-
- for (i = 0; i < count; i++) {
- if (*s == 10)
- prom_printf("%c", 13);
- prom_printf("%c", *s++);
- }
-}
-#endif
-
/*
* ------------------------------------------------------------
* dz_in () and dz_out ()
@@ -90,6 +78,7 @@ static inline unsigned short dz_in(struct dz_port *dport, unsigned offset)
{
volatile unsigned short *addr =
(volatile unsigned short *) (dport->port.membase + offset);
+
return *addr;
}
@@ -98,6 +87,7 @@ static inline void dz_out(struct dz_port *dport, unsigned offset,
{
volatile unsigned short *addr =
(volatile unsigned short *) (dport->port.membase + offset);
+
*addr = value;
}
@@ -144,7 +134,7 @@ static void dz_stop_rx(struct uart_port *uport)
spin_lock_irqsave(&dport->port.lock, flags);
dport->cflag &= ~DZ_CREAD;
- dz_out(dport, DZ_LPR, dport->cflag);
+ dz_out(dport, DZ_LPR, dport->cflag | dport->port.line);
spin_unlock_irqrestore(&dport->port.lock, flags);
}
@@ -155,14 +145,14 @@ static void dz_enable_ms(struct uart_port *port)
/*
* ------------------------------------------------------------
- * Here starts the interrupt handling routines. All of the
- * following subroutines are declared as inline and are folded
- * into dz_interrupt. They were separated out for readability's
- * sake.
*
- * Note: rs_interrupt() is a "fast" interrupt, which means that it
+ * Here start the interrupt handling routines. All of the following
+ * subroutines are declared as inline and are folded into
+ * dz_interrupt. They were separated out for readability's sake.
+ *
+ * Note: dz_interrupt() is a "fast" interrupt, which means that it
* runs with interrupts turned off. People who may want to modify
- * rs_interrupt() should try to keep the interrupt handler as fast as
+ * dz_interrupt() should try to keep the interrupt handler as fast as
* possible. After you are done making modifications, it is not a bad
* idea to do:
*
@@ -180,92 +170,74 @@ static void dz_enable_ms(struct uart_port *port)
* This routine deals with inputs from any lines.
* ------------------------------------------------------------
*/
-static inline void dz_receive_chars(struct dz_port *dport)
+static inline void dz_receive_chars(struct dz_port *dport_in,
+ struct pt_regs *regs)
{
+ struct dz_port *dport;
struct tty_struct *tty = NULL;
struct uart_icount *icount;
- int ignore = 0;
- unsigned short status, tmp;
+ int lines_rx[DZ_NB_PORT] = { [0 ... DZ_NB_PORT - 1] = 0 };
+ unsigned short status;
unsigned char ch, flag;
+ int i;
- /* this code is going to be a problem...
- the call to tty_flip_buffer is going to need
- to be rethought...
- */
- do {
- status = dz_in(dport, DZ_RBUF);
-
- /* punt so we don't get duplicate characters */
- if (!(status & DZ_DVAL))
- goto ignore_char;
-
-
- ch = UCHAR(status); /* grab the char */
- flag = TTY_NORMAL;
+ while ((status = dz_in(dport_in, DZ_RBUF)) & DZ_DVAL) {
+ dport = &dz_ports[LINE(status)];
+ tty = dport->port.info->tty; /* point to the proper dev */
-#if 0
- if (info->is_console) {
- if (ch == 0)
- return; /* it's a break ... */
- }
-#endif
+ ch = UCHAR(status); /* grab the char */
- tty = dport->port.info->tty;/* now tty points to the proper dev */
icount = &dport->port.icount;
-
- if (!tty)
- break;
-
icount->rx++;
- /* keep track of the statistics */
- if (status & (DZ_OERR | DZ_FERR | DZ_PERR)) {
- if (status & DZ_PERR) /* parity error */
- icount->parity++;
- else if (status & DZ_FERR) /* frame error */
- icount->frame++;
- if (status & DZ_OERR) /* overrun error */
- icount->overrun++;
-
- /* check to see if we should ignore the character
- and mask off conditions that should be ignored
+ flag = TTY_NORMAL;
+ if (status & DZ_FERR) { /* frame error */
+ /*
+ * There is no separate BREAK status bit, so
+ * treat framing errors as BREAKs for Magic SysRq
+ * and SAK; normally, otherwise.
*/
-
- if (status & dport->port.ignore_status_mask) {
- if (++ignore > 100)
- break;
- goto ignore_char;
- }
- /* mask off the error conditions we want to ignore */
- tmp = status & dport->port.read_status_mask;
-
- if (tmp & DZ_PERR) {
- flag = TTY_PARITY;
-#ifdef DEBUG_DZ
- debug_console("PERR\n", 5);
-#endif
- } else if (tmp & DZ_FERR) {
+ if (uart_handle_break(&dport->port))
+ continue;
+ if (dport->port.flags & UPF_SAK)
+ flag = TTY_BREAK;
+ else
flag = TTY_FRAME;
-#ifdef DEBUG_DZ
- debug_console("FERR\n", 5);
-#endif
- }
- if (tmp & DZ_OERR) {
-#ifdef DEBUG_DZ
- debug_console("OERR\n", 5);
-#endif
- tty_insert_flip_char(tty, ch, flag);
- ch = 0;
- flag = TTY_OVERRUN;
- }
+ } else if (status & DZ_OERR) /* overrun error */
+ flag = TTY_OVERRUN;
+ else if (status & DZ_PERR) /* parity error */
+ flag = TTY_PARITY;
+
+ /* keep track of the statistics */
+ switch (flag) {
+ case TTY_FRAME:
+ icount->frame++;
+ break;
+ case TTY_PARITY:
+ icount->parity++;
+ break;
+ case TTY_OVERRUN:
+ icount->overrun++;
+ break;
+ case TTY_BREAK:
+ icount->brk++;
+ break;
+ default:
+ break;
}
- tty_insert_flip_char(tty, ch, flag);
- ignore_char:
- ;
- } while (status & DZ_DVAL);
- if (tty)
- tty_flip_buffer_push(tty);
+ if (uart_handle_sysrq_char(&dport->port, ch, regs))
+ continue;
+
+ if ((status & dport->port.ignore_status_mask) == 0) {
+ uart_insert_char(&dport->port,
+ status, DZ_OERR, ch, flag);
+ lines_rx[LINE(status)] = 1;
+ }
+ }
+ for (i = 0; i < DZ_NB_PORT; i++)
+ if (lines_rx[i])
+ tty_flip_buffer_push(dz_ports[i].port.info->tty);
}
/*
@@ -275,26 +247,32 @@ static inline void dz_receive_chars(struct dz_port *dport)
* This routine deals with outputs to any lines.
* ------------------------------------------------------------
*/
-static inline void dz_transmit_chars(struct dz_port *dport)
+static inline void dz_transmit_chars(struct dz_port *dport_in)
{
- struct circ_buf *xmit = &dport->port.info->xmit;
+ struct dz_port *dport;
+ struct circ_buf *xmit;
+ unsigned short status;
unsigned char tmp;
- if (dport->port.x_char) { /* XON/XOFF chars */
+ status = dz_in(dport_in, DZ_CSR);
+ dport = &dz_ports[LINE(status)];
+ xmit = &dport->port.info->xmit;
+
+ if (dport->port.x_char) { /* XON/XOFF chars */
dz_out(dport, DZ_TDR, dport->port.x_char);
dport->port.icount.tx++;
dport->port.x_char = 0;
return;
}
- /* if nothing to do or stopped or hardware stopped */
+ /* If nothing to do or stopped or hardware stopped. */
if (uart_circ_empty(xmit) || uart_tx_stopped(&dport->port)) {
dz_stop_tx(&dport->port);
return;
}
/*
- * if something to do ... (rember the dz has no output fifo so we go
- * one char at a time :-<
+ * If something to do... (remember the dz has no output fifo,
+ * so we go one char at a time) :-<
*/
tmp = xmit->buf[xmit->tail];
xmit->tail = (xmit->tail + 1) & (DZ_XMIT_SIZE - 1);
@@ -304,23 +282,29 @@ static inline void dz_transmit_chars(struct dz_port *dport)
if (uart_circ_chars_pending(xmit) < DZ_WAKEUP_CHARS)
uart_write_wakeup(&dport->port);
- /* Are we done */
+ /* Are we are done. */
if (uart_circ_empty(xmit))
dz_stop_tx(&dport->port);
}
/*
* ------------------------------------------------------------
- * check_modem_status ()
+ * check_modem_status()
*
- * Only valid for the MODEM line duh !
+ * DS 3100 & 5100: Only valid for the MODEM line, duh!
+ * DS 5000/200: Valid for the MODEM and PRINTER line.
* ------------------------------------------------------------
*/
static inline void check_modem_status(struct dz_port *dport)
{
+ /*
+ * FIXME:
+ * 1. No status change interrupt; use a timer.
+ * 2. Handle the 3100/5000 as appropriate. --macro
+ */
unsigned short status;
- /* if not ne modem line just return */
+ /* If not the modem line just return. */
if (dport->port.line != DZ_MODEM)
return;
@@ -341,21 +325,18 @@ static inline void check_modem_status(struct dz_port *dport)
*/
static irqreturn_t dz_interrupt(int irq, void *dev)
{
- struct dz_port *dport;
+ struct dz_port *dport = (struct dz_port *)dev;
unsigned short status;
/* get the reason why we just got an irq */
- status = dz_in((struct dz_port *)dev, DZ_CSR);
- dport = &dz_ports[LINE(status)];
+ status = dz_in(dport, DZ_CSR);
- if (status & DZ_RDONE)
- dz_receive_chars(dport);
+ if ((status & (DZ_RDONE | DZ_RIE)) == (DZ_RDONE | DZ_RIE))
+ dz_receive_chars(dport, regs);
- if (status & DZ_TRDY)
+ if ((status & (DZ_TRDY | DZ_TIE)) == (DZ_TRDY | DZ_TIE))
dz_transmit_chars(dport);
- /* FIXME: what about check modem status??? --rmk */
-
return IRQ_HANDLED;
}
@@ -367,13 +348,13 @@ static irqreturn_t dz_interrupt(int irq, void *dev)
static unsigned int dz_get_mctrl(struct uart_port *uport)
{
+ /*
+ * FIXME: Handle the 3100/5000 as appropriate. --macro
+ */
struct dz_port *dport = (struct dz_port *)uport;
unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
if (dport->port.line == DZ_MODEM) {
- /*
- * CHECKME: This is a guess from the other code... --rmk
- */
if (dz_in(dport, DZ_MSR) & DZ_MODEM_DSR)
mctrl &= ~TIOCM_DSR;
}
@@ -383,6 +364,9 @@ static unsigned int dz_get_mctrl(struct uart_port *uport)
static void dz_set_mctrl(struct uart_port *uport, unsigned int mctrl)
{
+ /*
+ * FIXME: Handle the 3100/5000 as appropriate. --macro
+ */
struct dz_port *dport = (struct dz_port *)uport;
unsigned short tmp;
@@ -409,13 +393,6 @@ static int dz_startup(struct uart_port *uport)
unsigned long flags;
unsigned short tmp;
- /* The dz lines for the mouse/keyboard must be
- * opened using their respective drivers.
- */
- if ((dport->port.line == DZ_KEYBOARD) ||
- (dport->port.line == DZ_MOUSE))
- return -ENODEV;
-
spin_lock_irqsave(&dport->port.lock, flags);
/* enable the interrupt and the scanning */
@@ -442,7 +419,8 @@ static void dz_shutdown(struct uart_port *uport)
}
/*
- * get_lsr_info - get line status register info
+ * -------------------------------------------------------------------
+ * dz_tx_empty() -- get the transmitter empty status
*
* Purpose: Let user call ioctl() to get info when the UART physically
* is emptied. On bus types like RS485, the transmitter must
@@ -450,21 +428,28 @@ static void dz_shutdown(struct uart_port *uport)
* the transmit shift register is empty, not be done when the
* transmit holding register is empty. This functionality
* allows an RS485 driver to be written in user space.
+ * -------------------------------------------------------------------
*/
static unsigned int dz_tx_empty(struct uart_port *uport)
{
struct dz_port *dport = (struct dz_port *)uport;
- unsigned short status = dz_in(dport, DZ_LPR);
+ unsigned short tmp, mask = 1 << dport->port.line;
- /* FIXME: this appears to be obviously broken --rmk. */
- return status ? TIOCSER_TEMT : 0;
+ tmp = dz_in(dport, DZ_TCR);
+ tmp &= mask;
+
+ return tmp ? 0 : TIOCSER_TEMT;
}
static void dz_break_ctl(struct uart_port *uport, int break_state)
{
+ /*
+ * FIXME: Can't access BREAK bits in TDR easily;
+ * reuse the code for polled TX. --macro
+ */
struct dz_port *dport = (struct dz_port *)uport;
unsigned long flags;
- unsigned short tmp, mask = 1 << uport->line;
+ unsigned short tmp, mask = 1 << dport->port.line;
spin_lock_irqsave(&uport->lock, flags);
tmp = dz_in(dport, DZ_TCR);
@@ -561,7 +546,7 @@ static void dz_set_termios(struct uart_port *uport, struct termios *termios,
spin_lock_irqsave(&dport->port.lock, flags);
- dz_out(dport, DZ_LPR, cflag);
+ dz_out(dport, DZ_LPR, cflag | dport->port.line);
dport->cflag = cflag;
/* setup accept flag */
@@ -650,7 +635,7 @@ static void __init dz_init_ports(void)
for (i = 0, dport = dz_ports; i < DZ_NB_PORT; i++, dport++) {
spin_lock_init(&dport->port.lock);
dport->port.membase = (char *) base;
- dport->port.iotype = UPIO_PORT;
+ dport->port.iotype = UPIO_MEM;
dport->port.irq = dec_interrupt[DEC_IRQ_DZ11];
dport->port.line = i;
dport->port.fifosize = 1;
@@ -662,10 +647,7 @@ static void __init dz_init_ports(void)
static void dz_reset(struct dz_port *dport)
{
dz_out(dport, DZ_CSR, DZ_CLR);
-
while (dz_in(dport, DZ_CSR) & DZ_CLR);
- /* FIXME: cpu_relax? */
-
iob();
/* enable scanning */
@@ -673,26 +655,55 @@ static void dz_reset(struct dz_port *dport)
}
#ifdef CONFIG_SERIAL_DZ_CONSOLE
+/*
+ * -------------------------------------------------------------------
+ * dz_console_putchar() -- transmit a character
+ *
+ * Polled transmission. This is tricky. We need to mask transmit
+ * interrupts so that they do not interfere, enable the transmitter
+ * for the line requested and then wait till the transmit scanner
+ * requests data for this line. But it may request data for another
+ * line first, in which case we have to disable its transmitter and
+ * repeat waiting till our line pops up. Only then the character may
+ * be transmitted. Finally, the state of the transmitter mask is
+ * restored. Welcome to the world of PDP-11!
+ * -------------------------------------------------------------------
+ */
static void dz_console_putchar(struct uart_port *uport, int ch)
{
struct dz_port *dport = (struct dz_port *)uport;
unsigned long flags;
- int loops = 2500;
- unsigned short tmp = (unsigned char)ch;
- /* this code sends stuff out to serial device - spinning its
- wheels and waiting. */
+ unsigned short csr, tcr, trdy, mask;
+ int loops = 10000;
spin_lock_irqsave(&dport->port.lock, flags);
+ csr = dz_in(dport, DZ_CSR);
+ dz_out(dport, DZ_CSR, csr & ~DZ_TIE);
+ tcr = dz_in(dport, DZ_TCR);
+ tcr |= 1 << dport->port.line;
+ mask = tcr;
+ dz_out(dport, DZ_TCR, mask);
+ iob();
+ spin_unlock_irqrestore(&dport->port.lock, flags);
- /* spin our wheels */
- while (((dz_in(dport, DZ_CSR) & DZ_TRDY) != DZ_TRDY) && loops--)
- /* FIXME: cpu_relax, udelay? --rmk */
- ;
+ while (loops--) {
+ trdy = dz_in(dport, DZ_CSR);
+ if (!(trdy & DZ_TRDY))
+ continue;
+ trdy = (trdy & DZ_TLINE) >> 8;
+ if (trdy == dport->port.line)
+ break;
+ mask &= ~(1 << trdy);
+ dz_out(dport, DZ_TCR, mask);
+ iob();
+ udelay(2);
+ }
- /* Actually transmit the character. */
- dz_out(dport, DZ_TDR, tmp);
+ if (loops) /* Cannot send otherwise. */
+ dz_out(dport, DZ_TDR, ch);
- spin_unlock_irqrestore(&dport->port.lock, flags);
+ dz_out(dport, DZ_TCR, tcr);
+ dz_out(dport, DZ_CSR, csr);
}
/*
@@ -703,11 +714,11 @@ static void dz_console_putchar(struct uart_port *uport, int ch)
* The console must be locked when we get here.
* -------------------------------------------------------------------
*/
-static void dz_console_print(struct console *cons,
+static void dz_console_print(struct console *co,
const char *str,
unsigned int count)
{
- struct dz_port *dport = &dz_ports[CONSOLE_LINE];
+ struct dz_port *dport = &dz_ports[co->index];
#ifdef DEBUG_DZ
prom_printf((char *) str);
#endif
@@ -716,49 +727,43 @@ static void dz_console_print(struct console *cons,
static int __init dz_console_setup(struct console *co, char *options)
{
- struct dz_port *dport = &dz_ports[CONSOLE_LINE];
+ struct dz_port *dport = &dz_ports[co->index];
int baud = 9600;
int bits = 8;
int parity = 'n';
int flow = 'n';
- int ret;
- unsigned short mask, tmp;
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
dz_reset(dport);
- ret = uart_set_options(&dport->port, co, baud, parity, bits, flow);
- if (ret == 0) {
- mask = 1 << dport->port.line;
- tmp = dz_in(dport, DZ_TCR); /* read the TX flag */
- if (!(tmp & mask)) {
- tmp |= mask; /* set the TX flag */
- dz_out(dport, DZ_TCR, tmp);
- }
- }
-
- return ret;
+ return uart_set_options(&dport->port, co, baud, parity, bits, flow);
}
-static struct console dz_sercons =
-{
+static struct uart_driver dz_reg;
+static struct console dz_sercons = {
.name = "ttyS",
.write = dz_console_print,
.device = uart_console_device,
.setup = dz_console_setup,
- .flags = CON_CONSDEV | CON_PRINTBUFFER,
- .index = CONSOLE_LINE,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &dz_reg,
};
-void __init dz_serial_console_init(void)
+static int __init dz_serial_console_init(void)
{
- dz_init_ports();
-
- register_console(&dz_sercons);
+ if (!IOASIC) {
+ dz_init_ports();
+ register_console(&dz_sercons);
+ return 0;
+ } else
+ return -ENXIO;
}
+console_initcall(dz_serial_console_init);
+
#define SERIAL_DZ_CONSOLE &dz_sercons
#else
#define SERIAL_DZ_CONSOLE NULL
@@ -767,35 +772,29 @@ void __init dz_serial_console_init(void)
static struct uart_driver dz_reg = {
.owner = THIS_MODULE,
.driver_name = "serial",
- .dev_name = "ttyS%d",
+ .dev_name = "ttyS",
.major = TTY_MAJOR,
.minor = 64,
.nr = DZ_NB_PORT,
.cons = SERIAL_DZ_CONSOLE,
};
-int __init dz_init(void)
+static int __init dz_init(void)
{
- unsigned long flags;
int ret, i;
+ if (IOASIC)
+ return -ENXIO;
+
printk("%s%s\n", dz_name, dz_version);
dz_init_ports();
- save_flags(flags);
- cli();
-
#ifndef CONFIG_SERIAL_DZ_CONSOLE
/* reset the chip */
dz_reset(&dz_ports[0]);
#endif
- /* order matters here... the trick is that flags
- is updated... in request_irq - to immediatedly obliterate
- it is unwise. */
- restore_flags(flags);
-
if (request_irq(dz_ports[0].port.irq, dz_interrupt,
IRQF_DISABLED, "DZ", &dz_ports[0]))
panic("Unable to register DZ interrupt");
@@ -810,5 +809,7 @@ int __init dz_init(void)
return ret;
}
+module_init(dz_init);
+
MODULE_DESCRIPTION("DECstation DZ serial driver");
MODULE_LICENSE("GPL");