Messages in this thread Patch in this message | | | Date | Tue, 21 Oct 2003 16:26:04 -0500 | From | Patrick Gefre <> | Subject | [PATCH] Altix console driver |
| |
2.6 Altix serial console driver add
# This is a BitKeeper generated patch for the following project: # Project Name: Linux kernel tree # This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas: # ChangeSet 1.1347 -> 1.1348 # drivers/char/Kconfig 1.24 -> 1.25 # MAINTAINERS 1.174 -> 1.175 # drivers/char/Makefile 1.60 -> 1.61 # (new) -> 1.1 drivers/char/sn_serial.c # # The following is the BitKeeper ChangeSet Log # -------------------------------------------- # 03/10/21 pfg@attica.americas.sgi.com 1.1348 # Altix serial console patch # -------------------------------------------- # diff -Nru a/MAINTAINERS b/MAINTAINERS --- a/MAINTAINERS Tue Oct 21 16:18:17 2003 +++ b/MAINTAINERS Tue Oct 21 16:18:17 2003 @@ -1753,6 +1753,12 @@ W: http://www.nsa.gov/selinux S: Supported +SGI SN-IA64 (Altix) SERIAL CONSOLE DRIVER +P: Pat Gefre +M: pfg@sgi.com +L: linux-ia64@vger.kernel.org +S: Supported + SGI VISUAL WORKSTATION 320 AND 540 P: Andrey Panin M: pazke@donpac.ru diff -Nru a/drivers/char/Kconfig b/drivers/char/Kconfig --- a/drivers/char/Kconfig Tue Oct 21 16:18:17 2003 +++ b/drivers/char/Kconfig Tue Oct 21 16:18:17 2003 @@ -373,6 +373,22 @@ If you have an Alchemy AU1000 processor (MIPS based) and you want to use serial ports, say Y. Otherwise, say N. +config SGI_L1_SERIAL + bool "SGI Altix L1 serial support" + depends on SERIAL_NONSTANDARD && IA64 + help + If you have an SGI Altix and you want to use the serial port + connected to the system controller (you want this!), say Y. + Otherwise, say N. + +config SGI_L1_SERIAL_CONSOLE + bool "SGI Altix L1 serial console support" + depends on SGI_L1_SERIAL + help + If you have an SGI Altix and you would like to use the system + controller serial port as your console (you want this!), + say Y. Otherwise, say N. + config AU1000_SERIAL_CONSOLE bool "Enable Au1000 serial console" depends on AU1000_UART diff -Nru a/drivers/char/Makefile b/drivers/char/Makefile --- a/drivers/char/Makefile Tue Oct 21 16:18:17 2003 +++ b/drivers/char/Makefile Tue Oct 21 16:18:17 2003 @@ -42,6 +42,7 @@ obj-$(CONFIG_SH_SCI) += sh-sci.o generic_serial.o obj-$(CONFIG_HVC_CONSOLE) += hvc_console.o obj-$(CONFIG_RAW_DRIVER) += raw.o +obj-$(CONFIG_SGI_L1_SERIAL) += sn_serial.o obj-$(CONFIG_PRINTER) += lp.o obj-$(CONFIG_TIPAR) += tipar.o diff -Nru a/drivers/char/sn_serial.c b/drivers/char/sn_serial.c --- /dev/null Wed Dec 31 16:00:00 1969 +++ b/drivers/char/sn_serial.c Tue Oct 21 16:18:17 2003 @@ -0,0 +1,1000 @@ +/* + * C-Brick Serial Port (and console) driver for SGI Altix machines. + * + * This driver is NOT suitable for talking to the l1-controller for + * anything other than 'console activities' --- please use the l1 + * driver for that. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2003 Silicon Graphics, Inc. All rights reserved. + */ + +#include <linux/config.h> +#include <linux/interrupt.h> +#include <linux/tty.h> +#include <linux/serial.h> +#include <linux/console.h> +#include <linux/module.h> +#include <linux/sysrq.h> +#include <linux/circ_buf.h> +#include <linux/serial_reg.h> +#include <asm/sn/sn_sal.h> +#include <asm/sn/pci/pciio.h> /* this is needed for get_console_nasid */ +#include <asm/sn/simulator.h> +#include <asm/sn/sn2/sn_private.h> + +#if defined(CONFIG_SGI_L1_SERIAL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) +static char sysrq_serial_str[] = "\eSYS"; +static char *sysrq_serial_ptr = sysrq_serial_str; +static unsigned long sysrq_requested; +#endif /* CONFIG_SGI_L1_SERIAL_CONSOLE && CONFIG_MAGIC_SYSRQ */ + +/* minor device number */ +#define SN_SAL_MINOR 64 + +/* number of characters left in xmit buffer before we ask for more */ +#define WAKEUP_CHARS 128 + +/* number of characters we can transmit to the SAL console at a time */ +#define SN_SAL_MAX_CHARS 120 + +#define SN_SAL_EVENT_WRITE_WAKEUP 0 + +/* 64K, when we're asynch, it must be at least printk's LOG_BUF_LEN to + * avoid losing chars, (always has to be a power of 2) */ +#define SN_SAL_BUFFER_SIZE (64 * (1 << 10)) + +#define SN_SAL_UART_FIFO_DEPTH 16 +#define SN_SAL_UART_FIFO_SPEED_CPS 9600/10 + +/* we don't kmalloc/get_free_page these as we want them available + * before either of those are initialized */ +static char sn_xmit_buff_mem[SN_SAL_BUFFER_SIZE]; + +struct volatile_circ_buf { + char *cb_buf; + int cb_head; + int cb_tail; +}; + +static struct volatile_circ_buf xmit = { .cb_buf = sn_xmit_buff_mem }; +static char sn_tmp_buffer[SN_SAL_BUFFER_SIZE]; + +static struct tty_struct *sn_sal_tty; + +static struct timer_list sn_sal_timer; +static int sn_sal_event; /* event type for task queue */ + +static int sn_sal_is_asynch; +static int sn_sal_irq; +static spinlock_t sn_sal_lock = SPIN_LOCK_UNLOCKED; +static int sn_total_tx_count; +static int sn_total_rx_count; + +static void sn_sal_tasklet_action(unsigned long data); +static DECLARE_TASKLET(sn_sal_tasklet, sn_sal_tasklet_action, 0); + +static unsigned long sn_interrupt_timeout; + +extern u64 master_node_bedrock_address; + +static int sn_debug_printf(const char *fmt, ...); + +#undef DEBUG +#ifdef DEBUG +#define DPRINTF(x...) sn_debug_printf(x) +#else +#define DPRINTF(x...) do { } while (0) +#endif + +struct sn_sal_ops { + int (*sal_puts)(const char *s, int len); + int (*sal_getc)(void); + int (*sal_input_pending)(void); + void (*sal_wakeup_transmit)(void); +}; + +/* This is the pointer used. It is assigned to point to one of + * the tables below. + */ +static struct sn_sal_ops *sn_func; + +/* Prototypes */ +static void __init sn_sal_serial_console_init(void); +static int snt_hw_puts(const char *, int); +static int snt_poll_getc(void); +static int snt_poll_input_pending(void); +static int snt_sim_puts(const char *, int); +static int snt_sim_getc(void); +static int snt_sim_input_pending(void); +static int snt_intr_getc(void); +static int snt_intr_input_pending(void); +static void sn_intr_transmit_chars(void); + +/* A table for polling */ +static struct sn_sal_ops poll_ops = { + .sal_puts = snt_hw_puts, + .sal_getc = snt_poll_getc, + .sal_input_pending = snt_poll_input_pending +}; + +/* A table for the simulator */ +static struct sn_sal_ops sim_ops = { + .sal_puts = snt_sim_puts, + .sal_getc = snt_sim_getc, + .sal_input_pending = snt_sim_input_pending +}; + +/* A table for interrupts enabled */ +static struct sn_sal_ops intr_ops = { + .sal_puts = snt_hw_puts, + .sal_getc = snt_intr_getc, + .sal_input_pending = snt_intr_input_pending, + .sal_wakeup_transmit = sn_intr_transmit_chars +}; + + +/* the console does output in two distinctly different ways: + * synchronous and asynchronous (buffered). initally, early_printk + * does synchronous output. any data written goes directly to the SAL + * to be output (incidentally, it is internally buffered by the SAL) + * after interrupts and timers are initialized and available for use, + * the console init code switches to asynchronous output. this is + * also the earliest opportunity to begin polling for console input. + * after console initialization, console output and tty (serial port) + * output is buffered and sent to the SAL asynchronously (either by + * timer callback or by UART interrupt) */ + + +/* routines for running the console in polling mode */ + +static int +snt_hw_puts(const char *s, int len) +{ + /* looking at the PROM source code, putb calls the flush + * routine, so if we send characters in FIFO sized chunks, it + * should go out by the next time the timer gets called */ + return ia64_sn_console_putb(s, len); +} + +static int +snt_poll_getc(void) +{ + int ch; + ia64_sn_console_getc(&ch); + return ch; +} + +static int +snt_poll_input_pending(void) +{ + int status, input; + + status = ia64_sn_console_check(&input); + return !status && input; +} + + +/* routines for running the console on the simulator */ + +static int +snt_sim_puts(const char *str, int count) +{ + int counter = count; + +#ifdef FLAG_DIRECT_CONSOLE_WRITES + /* This is an easy way to pre-pend the output to know whether the output + * was done via sal or directly */ + writeb('[', master_node_bedrock_address + (UART_TX << 3)); + writeb('+', master_node_bedrock_address + (UART_TX << 3)); + writeb(']', master_node_bedrock_address + (UART_TX << 3)); + writeb(' ', master_node_bedrock_address + (UART_TX << 3)); +#endif /* FLAG_DIRECT_CONSOLE_WRITES */ + while (counter > 0) { + writeb(*str, master_node_bedrock_address + (UART_TX << 3)); + counter--; + str++; + } + + return count; +} + +static int +snt_sim_getc(void) +{ + return readb(master_node_bedrock_address + (UART_RX << 3)); +} + +static int +snt_sim_input_pending(void) +{ + return readb(master_node_bedrock_address + (UART_LSR << 3)) & UART_LSR_DR; +} + + +/* routines for an interrupt driven console (normal) */ + +static int +snt_intr_getc(void) +{ + return ia64_sn_console_readc(); +} + +static int +snt_intr_input_pending(void) +{ + return ia64_sn_console_intr_status() & SAL_CONSOLE_INTR_RECV; +} + +/* The early printk (possible setup) and function call */ + +void +early_printk_sn_sal(const char *s, unsigned count) +{ + extern void early_sn_setup(void); + + if (!sn_func) { + if (IS_RUNNING_ON_SIMULATOR()) + sn_func = &sim_ops; + else + sn_func = &poll_ops; + + early_sn_setup(); + } + sn_func->sal_puts(s, count); +} + +/* this is as "close to the metal" as we can get, used when the driver + * itself may be broken */ +static int +sn_debug_printf(const char *fmt, ...) +{ + static char printk_buf[1024]; + int printed_len; + va_list args; + + va_start(args, fmt); + printed_len = vsnprintf(printk_buf, sizeof(printk_buf), fmt, args); + early_printk_sn_sal(printk_buf, printed_len); + va_end(args); + return printed_len; +} + +/* + * Interrupt handling routines. + */ + +static void +sn_sal_sched_event(int event) +{ + sn_sal_event |= (1 << event); + tasklet_schedule(&sn_sal_tasklet); +} + +/* sn_receive_chars can be called before sn_sal_tty is initialized. in + * that case, its only use is to trigger sysrq and kdb */ +static void +sn_receive_chars(struct pt_regs *regs, unsigned long *flags) +{ + int ch; + + while (sn_func->sal_input_pending()) { + ch = sn_func->sal_getc(); + if (ch < 0) { + printk(KERN_ERR "sn_serial: An error occured while " + "obtaining data from the console (0x%0x)\n", ch); + break; + } +#if defined(CONFIG_SGI_L1_SERIAL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) + if (sysrq_requested) { + unsigned long sysrq_timeout = sysrq_requested + HZ*5; + + sysrq_requested = 0; + if (ch && time_before(jiffies, sysrq_timeout)) { + spin_unlock_irqrestore(&sn_sal_lock, *flags); + handle_sysrq(ch, regs, NULL); + spin_lock_irqsave(&sn_sal_lock, *flags); + /* don't record this char */ + continue; + } + } + if (ch == *sysrq_serial_ptr) { + if (!(*++sysrq_serial_ptr)) { + sysrq_requested = jiffies; + sysrq_serial_ptr = sysrq_serial_str; + } + } + else + sysrq_serial_ptr = sysrq_serial_str; +#endif /* CONFIG_SGI_L1_SERIAL_CONSOLE && CONFIG_MAGIC_SYSRQ */ + + /* record the character to pass up to the tty layer */ + if (sn_sal_tty) { + *sn_sal_tty->flip.char_buf_ptr = ch; + sn_sal_tty->flip.char_buf_ptr++; + sn_sal_tty->flip.count++; + if (sn_sal_tty->flip.count == TTY_FLIPBUF_SIZE) + break; + } + sn_total_rx_count++; + } + + if (sn_sal_tty) + tty_flip_buffer_push((struct tty_struct *)sn_sal_tty); +} + + +/* synch_flush_xmit must be called with sn_sal_lock */ +static void +synch_flush_xmit(void) +{ + int xmit_count, tail, head, loops, ii; + int result; + char *start; + + if (xmit.cb_head == xmit.cb_tail) + return; /* Nothing to do. */ + + head = xmit.cb_head; + tail = xmit.cb_tail; + start = &xmit.cb_buf[tail]; + + /* twice around gets the tail to the end of the buffer and + * then to the head, if needed */ + loops = (head < tail) ? 2 : 1; + + for (ii = 0; ii < loops; ii++) { + xmit_count = (head < tail) ? (SN_SAL_BUFFER_SIZE - tail) : (head - tail); + + if (xmit_count > 0) { + result = sn_func->sal_puts((char *)start, xmit_count); + if (!result) + sn_debug_printf("\n*** synch_flush_xmit failed to flush\n"); + if (result > 0) { + xmit_count -= result; + sn_total_tx_count += result; + tail += result; + tail &= SN_SAL_BUFFER_SIZE - 1; + xmit.cb_tail = tail; + start = (char *)&xmit.cb_buf[tail]; + } + } + } +} + +/* must be called with a lock protecting the circular buffer and + * sn_sal_tty */ +static void +sn_poll_transmit_chars(void) +{ + int xmit_count, tail, head; + int result; + char *start; + + BUG_ON(!sn_sal_is_asynch); + + if (xmit.cb_head == xmit.cb_tail || + (sn_sal_tty && (sn_sal_tty->stopped || sn_sal_tty->hw_stopped))) { + /* Nothing to do. */ + return; + } + + head = xmit.cb_head; + tail = xmit.cb_tail; + start = &xmit.cb_buf[tail]; + + xmit_count = (head < tail) ? (SN_SAL_BUFFER_SIZE - tail) : (head - tail); + + if (xmit_count == 0) + sn_debug_printf("\n*** empty xmit_count\n"); + + /* use the ops, as we could be on the simulator */ + result = sn_func->sal_puts((char *)start, xmit_count); + if (!result) + sn_debug_printf("\n*** error in synchronous sal_puts\n"); + /* XXX chadt clean this up */ + if (result > 0) { + xmit_count -= result; + sn_total_tx_count += result; + tail += result; + tail &= SN_SAL_BUFFER_SIZE - 1; + xmit.cb_tail = tail; + start = &xmit.cb_buf[tail]; + } + + /* if there's few enough characters left in the xmit buffer + * that we could stand for the upper layer to send us some + * more, ask for it. */ + if (sn_sal_tty) + if (CIRC_CNT(xmit.cb_head, xmit.cb_tail, SN_SAL_BUFFER_SIZE) < WAKEUP_CHARS) + sn_sal_sched_event(SN_SAL_EVENT_WRITE_WAKEUP); +} + + +/* must be called with a lock protecting the circular buffer and + * sn_sal_tty */ +static void +sn_intr_transmit_chars(void) +{ + int xmit_count, tail, head, loops, ii; + int result; + char *start; + + BUG_ON(!sn_sal_is_asynch); + + if (xmit.cb_head == xmit.cb_tail || + (sn_sal_tty && (sn_sal_tty->stopped || sn_sal_tty->hw_stopped))) { + /* Nothing to do. */ + return; + } + + head = xmit.cb_head; + tail = xmit.cb_tail; + start = &xmit.cb_buf[tail]; + + /* twice around gets the tail to the end of the buffer and + * then to the head, if needed */ + loops = (head < tail) ? 2 : 1; + + for (ii = 0; ii < loops; ii++) { + xmit_count = (head < tail) ? + (SN_SAL_BUFFER_SIZE - tail) : (head - tail); + + if (xmit_count > 0) { + result = ia64_sn_console_xmit_chars((char *)start, xmit_count); +#ifdef DEBUG + if (!result) + sn_debug_printf("`"); +#endif + if (result > 0) { + xmit_count -= result; + sn_total_tx_count += result; + tail += result; + tail &= SN_SAL_BUFFER_SIZE - 1; + xmit.cb_tail = tail; + start = &xmit.cb_buf[tail]; + } + } + } + + /* if there's few enough characters left in the xmit buffer + * that we could stand for the upper layer to send us some + * more, ask for it. */ + if (sn_sal_tty) + if (CIRC_CNT(xmit.cb_head, xmit.cb_tail, SN_SAL_BUFFER_SIZE) < WAKEUP_CHARS) + sn_sal_sched_event(SN_SAL_EVENT_WRITE_WAKEUP); +} + + +static irqreturn_t +sn_sal_interrupt(int irq, void *dev_id, struct pt_regs *regs) +{ + /* this call is necessary to pass the interrupt back to the + * SAL, since it doesn't intercept the UART interrupts + * itself */ + int status = ia64_sn_console_intr_status(); + unsigned long flags; + + spin_lock_irqsave(&sn_sal_lock, flags); + if (status & SAL_CONSOLE_INTR_RECV) + sn_receive_chars(regs, &flags); + if (status & SAL_CONSOLE_INTR_XMIT) + sn_intr_transmit_chars(); + spin_unlock_irqrestore(&sn_sal_lock, flags); + return IRQ_HANDLED; +} + + +/* returns the console irq if interrupt is successfully registered, + * else 0 */ +static int +sn_sal_connect_interrupt(void) +{ + cpuid_t intr_cpuid; + unsigned int intr_cpuloc; + nasid_t console_nasid; + unsigned int console_irq; + int result; + + console_nasid = ia64_sn_get_console_nasid(); + intr_cpuid = NODEPDA(NASID_TO_COMPACT_NODEID(console_nasid))->node_first_cpu; + intr_cpuloc = cpu_physical_id(intr_cpuid); + console_irq = CPU_VECTOR_TO_IRQ(intr_cpuloc, SGI_UART_VECTOR); + + result = intr_connect_level(intr_cpuid, SGI_UART_VECTOR); + BUG_ON(result != SGI_UART_VECTOR); + + result = request_irq(console_irq, sn_sal_interrupt, SA_INTERRUPT, "SAL console driver", &sn_sal_tty); + if (result >= 0) + return console_irq; + + printk(KERN_INFO "sn_serial: console proceeding in polled mode\n"); + return 0; +} + +static void +sn_sal_tasklet_action(unsigned long data) +{ + unsigned long flags; + + if (sn_sal_tty) { + spin_lock_irqsave(&sn_sal_lock, flags); + if (sn_sal_tty) { + if (test_and_clear_bit(SN_SAL_EVENT_WRITE_WAKEUP, &sn_sal_event)) { + if ((sn_sal_tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && sn_sal_tty->ldisc.write_wakeup) + (sn_sal_tty->ldisc.write_wakeup)((struct tty_struct *)sn_sal_tty); + wake_up_interruptible((wait_queue_head_t *)&sn_sal_tty->write_wait); + } + } + spin_unlock_irqrestore(&sn_sal_lock, flags); + } +} + + +/* + * This function handles polled mode. + */ +static void +sn_sal_timer_poll(unsigned long dummy) +{ + unsigned long flags; + + if (!sn_sal_irq) { + spin_lock_irqsave(&sn_sal_lock, flags); + sn_receive_chars(NULL, &flags); + sn_poll_transmit_chars(); + spin_unlock_irqrestore(&sn_sal_lock, flags); + mod_timer(&sn_sal_timer, jiffies + sn_interrupt_timeout); + } +} + + +/* + * User-level console routines + */ + +static int +sn_sal_open(struct tty_struct *tty, struct file *filp) +{ + unsigned long flags; + + DPRINTF("sn_sal_open: sn_sal_tty = %p, tty = %p, filp = %p\n", + sn_sal_tty, tty, filp); + + spin_lock_irqsave(&sn_sal_lock, flags); + if (!sn_sal_tty) + sn_sal_tty = tty; + spin_unlock_irqrestore(&sn_sal_lock, flags); + + return 0; +} + + +/* We're keeping all our resources. We're keeping interrupts turned + * on. Maybe just let the tty layer finish its stuff...? GMSH + */ +static void +sn_sal_close(struct tty_struct *tty, struct file * filp) +{ + if (tty->count == 1) { + unsigned long flags; + tty->closing = 1; + if (tty->driver->flush_buffer) + tty->driver->flush_buffer(tty); + if (tty->ldisc.flush_buffer) + tty->ldisc.flush_buffer(tty); + tty->closing = 0; + spin_lock_irqsave(&sn_sal_lock, flags); + sn_sal_tty = NULL; + spin_unlock_irqrestore(&sn_sal_lock, flags); + } +} + + +static int +sn_sal_write(struct tty_struct *tty, int from_user, + const unsigned char *buf, int count) +{ + int c, ret = 0; + unsigned long flags; + + if (from_user) { + while (1) { + int c1; + c = CIRC_SPACE_TO_END(xmit.cb_head, xmit.cb_tail, + SN_SAL_BUFFER_SIZE); + + if (count < c) + c = count; + if (c <= 0) + break; + + c -= copy_from_user(sn_tmp_buffer, buf, c); + if (!c) { + if (!ret) + ret = -EFAULT; + break; + } + + /* Turn off interrupts and see if the xmit buffer has + * moved since the last time we looked. + */ + spin_lock_irqsave(&sn_sal_lock, flags); + c1 = CIRC_SPACE_TO_END(xmit.cb_head, xmit.cb_tail, SN_SAL_BUFFER_SIZE); + + if (c1 < c) + c = c1; + + memcpy(xmit.cb_buf + xmit.cb_head, sn_tmp_buffer, c); + xmit.cb_head = ((xmit.cb_head + c) & (SN_SAL_BUFFER_SIZE - 1)); + spin_unlock_irqrestore(&sn_sal_lock, flags); + + buf += c; + count -= c; + ret += c; + } + } + else { + /* The buffer passed in isn't coming from userland, + * so cut out the middleman (sn_tmp_buffer). + */ + spin_lock_irqsave(&sn_sal_lock, flags); + while (1) { + c = CIRC_SPACE_TO_END(xmit.cb_head, xmit.cb_tail, SN_SAL_BUFFER_SIZE); + + if (count < c) + c = count; + if (c <= 0) { + break; + } + memcpy(xmit.cb_buf + xmit.cb_head, buf, c); + xmit.cb_head = ((xmit.cb_head + c) & (SN_SAL_BUFFER_SIZE - 1)); + buf += c; + count -= c; + ret += c; + } + spin_unlock_irqrestore(&sn_sal_lock, flags); + } + + spin_lock_irqsave(&sn_sal_lock, flags); + if (xmit.cb_head != xmit.cb_tail && !(tty && (tty->stopped || tty->hw_stopped))) + if (sn_func->sal_wakeup_transmit) + sn_func->sal_wakeup_transmit(); + spin_unlock_irqrestore(&sn_sal_lock, flags); + + return ret; +} + + +static void +sn_sal_put_char(struct tty_struct *tty, unsigned char ch) +{ + unsigned long flags; + + spin_lock_irqsave(&sn_sal_lock, flags); + if (CIRC_SPACE(xmit.cb_head, xmit.cb_tail, SN_SAL_BUFFER_SIZE) != 0) { + xmit.cb_buf[xmit.cb_head] = ch; + xmit.cb_head = (xmit.cb_head + 1) & (SN_SAL_BUFFER_SIZE-1); + if ( sn_func->sal_wakeup_transmit ) + sn_func->sal_wakeup_transmit(); + } + spin_unlock_irqrestore(&sn_sal_lock, flags); +} + + +static void +sn_sal_flush_chars(struct tty_struct *tty) +{ + unsigned long flags; + + spin_lock_irqsave(&sn_sal_lock, flags); + if (CIRC_CNT(xmit.cb_head, xmit.cb_tail, SN_SAL_BUFFER_SIZE)) + if (sn_func->sal_wakeup_transmit) + sn_func->sal_wakeup_transmit(); + spin_unlock_irqrestore(&sn_sal_lock, flags); +} + + +static int +sn_sal_write_room(struct tty_struct *tty) +{ + unsigned long flags; + int space; + + spin_lock_irqsave(&sn_sal_lock, flags); + space = CIRC_SPACE(xmit.cb_head, xmit.cb_tail, SN_SAL_BUFFER_SIZE); + spin_unlock_irqrestore(&sn_sal_lock, flags); + return space; +} + + +static int +sn_sal_chars_in_buffer(struct tty_struct *tty) +{ + unsigned long flags; + int space; + + spin_lock_irqsave(&sn_sal_lock, flags); + space = CIRC_CNT(xmit.cb_head, xmit.cb_tail, SN_SAL_BUFFER_SIZE); + DPRINTF("<%d>", space); + spin_unlock_irqrestore(&sn_sal_lock, flags); + return space; +} + + +static void +sn_sal_flush_buffer(struct tty_struct *tty) +{ + unsigned long flags; + + /* drop everything */ + spin_lock_irqsave(&sn_sal_lock, flags); + xmit.cb_head = xmit.cb_tail = 0; + spin_unlock_irqrestore(&sn_sal_lock, flags); + + /* wake up tty level */ + wake_up_interruptible(&tty->write_wait); + if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup) + (tty->ldisc.write_wakeup)(tty); +} + + +static void +sn_sal_hangup(struct tty_struct *tty) +{ + sn_sal_flush_buffer(tty); +} + + +static void +sn_sal_wait_until_sent(struct tty_struct *tty, int timeout) +{ + /* this is SAL's problem */ + DPRINTF("<sn_serial: should wait until sent>"); +} + + +/* + * sn_sal_read_proc + * + * Console /proc interface + */ + +static int +sn_sal_read_proc(char *page, char **start, off_t off, int count, + int *eof, void *data) +{ + int len = 0; + off_t begin = 0; + + len += sprintf(page, "sn_serial: nasid:%d irq:%d tx:%d rx:%d\n", + get_console_nasid(), sn_sal_irq, + sn_total_tx_count, sn_total_rx_count); + *eof = 1; + + if (off >= len+begin) + return 0; + *start = page + (off-begin); + + return count < begin+len-off ? count : begin+len-off; +} + + +static struct tty_operations sn_sal_driver_ops = { + .open = sn_sal_open, + .close = sn_sal_close, + .write = sn_sal_write, + .put_char = sn_sal_put_char, + .flush_chars = sn_sal_flush_chars, + .write_room = sn_sal_write_room, + .chars_in_buffer = sn_sal_chars_in_buffer, + .hangup = sn_sal_hangup, + .wait_until_sent = sn_sal_wait_until_sent, + .read_proc = sn_sal_read_proc, +}; +static struct tty_driver *sn_sal_driver; + +/* sn_sal_init wishlist: + * - allocate sn_tmp_buffer + * - fix up the tty_driver struct + * - turn on receive interrupts + * - do any termios twiddling once and for all + */ + +/* + * Boot-time initialization code + */ + +static void __init +sn_sal_switch_to_asynch(void) +{ + unsigned long flags; + + sn_debug_printf("sn_serial: about to switch to asynchronous console\n"); + + /* without early_printk, we may be invoked late enough to race + * with other cpus doing console IO at this point, however + * console interrupts will never be enabled */ + spin_lock_irqsave(&sn_sal_lock, flags); + + /* early_printk invocation may have done this for us */ + if (!sn_func) { + if (IS_RUNNING_ON_SIMULATOR()) + sn_func = &sim_ops; + else + sn_func = &poll_ops; + } + + /* we can't turn on the console interrupt (as request_irq + * calls kmalloc, which isn't set up yet), so we rely on a + * timer to poll for input and push data from the console + * buffer. + */ + init_timer(&sn_sal_timer); + sn_sal_timer.function = sn_sal_timer_poll; + + if (IS_RUNNING_ON_SIMULATOR()) + sn_interrupt_timeout = 6; + else { + /* 960cps / 16 char FIFO = 60HZ + * HZ / (SN_SAL_FIFO_SPEED_CPS / SN_SAL_FIFO_DEPTH) */ + sn_interrupt_timeout = HZ * SN_SAL_UART_FIFO_DEPTH / SN_SAL_UART_FIFO_SPEED_CPS; + } + mod_timer(&sn_sal_timer, jiffies + sn_interrupt_timeout); + + sn_sal_is_asynch = 1; + spin_unlock_irqrestore(&sn_sal_lock, flags); +} + +static void __init +sn_sal_switch_to_interrupts(void) +{ + int irq; + + sn_debug_printf("sn_serial: switching to interrupt driven console\n"); + + irq = sn_sal_connect_interrupt(); + if (irq) { + unsigned long flags; + spin_lock_irqsave(&sn_sal_lock, flags); + + /* sn_sal_irq is a global variable. When it's set to + * a non-zero value, we stop polling for input (since + * interrupts should now be enabled). */ + sn_sal_irq = irq; + sn_func = &intr_ops; + + /* turn on receive interrupts */ + ia64_sn_console_intr_enable(SAL_CONSOLE_INTR_RECV); + spin_unlock_irqrestore(&sn_sal_lock, flags); + } +} + +static int __init +sn_sal_module_init(void) +{ + int retval; + + printk("sn_serial: sn_sal_module_init\n"); + + if (!ia64_platform_is("sn2")) + return -ENODEV; + + sn_sal_driver = alloc_tty_driver(1); + if ( !sn_sal_driver ) + return -ENOMEM; + + sn_sal_driver->owner = THIS_MODULE; + sn_sal_driver->driver_name = "sn_serial"; + sn_sal_driver->name = "ttyS"; + sn_sal_driver->major = TTY_MAJOR; + sn_sal_driver->minor_start = SN_SAL_MINOR; + sn_sal_driver->type = TTY_DRIVER_TYPE_SERIAL; + sn_sal_driver->subtype = SERIAL_TYPE_NORMAL; + sn_sal_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS; + + tty_set_operations(sn_sal_driver, &sn_sal_driver_ops); + + /* when this driver is compiled in, the console initialization + * will have already switched us into asynchronous operation + * before we get here through the module initcalls */ + if (!sn_sal_is_asynch) + sn_sal_switch_to_asynch(); + + /* at this point (module_init) we can try to turn on interrupts */ + if (!IS_RUNNING_ON_SIMULATOR()) + sn_sal_switch_to_interrupts(); + + sn_sal_driver->init_termios = tty_std_termios; + sn_sal_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL; + + if ((retval = tty_register_driver(sn_sal_driver))) { + printk(KERN_ERR "sn_serial: Unable to register tty driver\n"); + return retval; + } +#ifdef CONFIG_SGI_L1_SERIAL_CONSOLE + sn_sal_serial_console_init(); +#endif /* CONFIG_SGI_L1_SERIAL_CONSOLE */ + return 0; +} + + +static void __exit +sn_sal_module_exit(void) +{ + del_timer_sync(&sn_sal_timer); + tty_unregister_driver(sn_sal_driver); + put_tty_driver(sn_sal_driver); +} + +module_init(sn_sal_module_init); +module_exit(sn_sal_module_exit); + +/* + * Kernel console definitions + */ + +#ifdef CONFIG_SGI_L1_SERIAL_CONSOLE +/* + * Print a string to the SAL console. The console_lock must be held + * when we get here. + */ +static void +sn_sal_console_write(struct console *co, const char *s, unsigned count) +{ + unsigned long flags; + + BUG_ON(!sn_sal_is_asynch); + + /* somebody really wants this output, might be an + * oops, kdb, panic, etc. make sure they get it. */ + if (spin_is_locked(&sn_sal_lock)) { + synch_flush_xmit(); + sn_func->sal_puts(s, count); + } + else if (in_interrupt()) { + spin_lock_irqsave(&sn_sal_lock, flags); + synch_flush_xmit(); + spin_unlock_irqrestore(&sn_sal_lock, flags); + sn_func->sal_puts(s, count); + } + else + sn_sal_write(NULL, 0, s, count); +} + +static struct tty_driver * +sn_sal_console_device(struct console *c, int *index) +{ + *index = c->index; + return sn_sal_driver; +} + +static int __init +sn_sal_console_setup(struct console *co, char *options) +{ + return 0; +} + + +static struct console sal_console = { + .name = "ttyS", + .write = sn_sal_console_write, + .device = sn_sal_console_device, + .setup = sn_sal_console_setup, + .index = -1 +}; + +static void __init +sn_sal_serial_console_init(void) +{ + if (ia64_platform_is("sn2")) { + sn_sal_switch_to_asynch(); + sn_debug_printf("sn_sal_serial_console_init : register console\n"); + register_console(&sal_console); + } +} + +#endif /* CONFIG_SGI_L1_SERIAL_CONSOLE */ | |