diff options
Diffstat (limited to 'drivers/char/hvc_console.c')
-rw-r--r-- | drivers/char/hvc_console.c | 429 |
1 files changed, 234 insertions, 195 deletions
diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c index 88cd858..cddb789 100644 --- a/drivers/char/hvc_console.c +++ b/drivers/char/hvc_console.c @@ -22,6 +22,7 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ +#include <linux/config.h> #include <linux/console.h> #include <linux/cpumask.h> #include <linux/init.h> @@ -40,7 +41,6 @@ #include <linux/delay.h> #include <asm/uaccess.h> #include <asm/hvconsole.h> -#include <asm/vio.h> #define HVC_MAJOR 229 #define HVC_MINOR 0 @@ -61,16 +61,21 @@ */ #define HVC_ALLOC_TTY_ADAPTERS 8 -static struct tty_driver *hvc_driver; -#ifdef CONFIG_MAGIC_SYSRQ -static int sysrq_pressed; -#endif - #define N_OUTBUF 16 #define N_INBUF 16 #define __ALIGNED__ __attribute__((__aligned__(8))) +static struct tty_driver *hvc_driver; +static struct task_struct *hvc_task; + +/* Picks up late kicks after list walk but before schedule() */ +static int hvc_kicked; + +#ifdef CONFIG_MAGIC_SYSRQ +static int sysrq_pressed; +#endif + struct hvc_struct { spinlock_t lock; int index; @@ -80,11 +85,11 @@ struct hvc_struct { char outbuf[N_OUTBUF] __ALIGNED__; int n_outbuf; uint32_t vtermno; + struct hv_ops *ops; int irq_requested; int irq; struct list_head next; struct kobject kobj; /* ref count & hvc_struct lifetime */ - struct vio_dev *vdev; }; /* dynamic list of hvc_struct instances */ @@ -97,26 +102,185 @@ static struct list_head hvc_structs = LIST_HEAD_INIT(hvc_structs); static DEFINE_SPINLOCK(hvc_structs_lock); /* + * This value is used to assign a tty->index value to a hvc_struct based + * upon order of exposure via hvc_probe(), when we can not match it to + * a console canidate registered with hvc_instantiate(). + */ +static int last_hvc = -1; + +/* + * Do not call this function with either the hvc_strucst_lock or the hvc_struct + * lock held. If successful, this function increments the kobject reference + * count against the target hvc_struct so it should be released when finished. + */ +struct hvc_struct *hvc_get_by_index(int index) +{ + struct hvc_struct *hp; + unsigned long flags; + + spin_lock(&hvc_structs_lock); + + list_for_each_entry(hp, &hvc_structs, next) { + spin_lock_irqsave(&hp->lock, flags); + if (hp->index == index) { + kobject_get(&hp->kobj); + spin_unlock_irqrestore(&hp->lock, flags); + spin_unlock(&hvc_structs_lock); + return hp; + } + spin_unlock_irqrestore(&hp->lock, flags); + } + hp = NULL; + + spin_unlock(&hvc_structs_lock); + return hp; +} + + +/* * Initial console vtermnos for console API usage prior to full console * initialization. Any vty adapter outside this range will not have usable * console interfaces but can still be used as a tty device. This has to be * static because kmalloc will not work during early console init. */ -static uint32_t vtermnos[MAX_NR_HVC_CONSOLES]; +static struct hv_ops *cons_ops[MAX_NR_HVC_CONSOLES]; +static uint32_t vtermnos[MAX_NR_HVC_CONSOLES] = + {[0 ... MAX_NR_HVC_CONSOLES - 1] = -1}; -/* Used for accounting purposes */ -static int num_vterms = 0; +/* + * Console APIs, NOT TTY. These APIs are available immediately when + * hvc_console_setup() finds adapters. + */ -static struct task_struct *hvc_task; +void hvc_console_print(struct console *co, const char *b, unsigned count) +{ + char c[16] __ALIGNED__; + unsigned i = 0, n = 0; + int r, donecr = 0, index = co->index; + + /* Console access attempt outside of acceptable console range. */ + if (index >= MAX_NR_HVC_CONSOLES) + return; + + /* This console adapter was removed so it is not useable. */ + if (vtermnos[index] < 0) + return; + + while (count > 0 || i > 0) { + if (count > 0 && i < sizeof(c)) { + if (b[n] == '\n' && !donecr) { + c[i++] = '\r'; + donecr = 1; + } else { + c[i++] = b[n++]; + donecr = 0; + --count; + } + } else { + r = cons_ops[index]->put_chars(vtermnos[index], c, i); + if (r < 0) { + /* throw away chars on error */ + i = 0; + } else if (r > 0) { + i -= r; + if (i > 0) + memmove(c, c+r, i); + } + } + } +} + +static struct tty_driver *hvc_console_device(struct console *c, int *index) +{ + if (vtermnos[c->index] == -1) + return NULL; + + *index = c->index; + return hvc_driver; +} + +static int __init hvc_console_setup(struct console *co, char *options) +{ + if (co->index < 0 || co->index >= MAX_NR_HVC_CONSOLES) + return -ENODEV; + + if (vtermnos[co->index] == -1) + return -ENODEV; + + return 0; +} + +struct console hvc_con_driver = { + .name = "hvc", + .write = hvc_console_print, + .device = hvc_console_device, + .setup = hvc_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, +}; /* - * This value is used to associate a tty->index value to a hvc_struct based - * upon order of exposure via hvc_probe(). + * Early console initialization. Preceeds driver initialization. + * + * (1) we are first, and the user specified another driver + * -- index will remain -1 + * (2) we are first and the user specified no driver + * -- index will be set to 0, then we will fail setup. + * (3) we are first and the user specified our driver + * -- index will be set to user specified driver, and we will fail + * (4) we are after driver, and this initcall will register us + * -- if the user didn't specify a driver then the console will match + * + * Note that for cases 2 and 3, we will match later when the io driver + * calls hvc_instantiate() and call register again. */ -static int hvc_count = -1; +static int __init hvc_console_init(void) +{ + register_console(&hvc_con_driver); + return 0; +} +console_initcall(hvc_console_init); -/* Picks up late kicks after list walk but before schedule() */ -static int hvc_kicked; +/* + * hvc_instantiate() is an early console discovery method which locates + * consoles * prior to the vio subsystem discovering them. Hotplugged + * vty adapters do NOT get an hvc_instantiate() callback since they + * appear after early console init. + */ +int hvc_instantiate(uint32_t vtermno, int index, struct hv_ops *ops) +{ + struct hvc_struct *hp; + + if (index < 0 || index >= MAX_NR_HVC_CONSOLES) + return -1; + + if (vtermnos[index] != -1) + return -1; + + /* make sure no no tty has been registerd in this index */ + hp = hvc_get_by_index(index); + if (hp) { + kobject_put(&hp->kobj); + return -1; + } + + vtermnos[index] = vtermno; + cons_ops[index] = ops; + + /* reserve all indices upto and including this index */ + if (last_hvc < index) + last_hvc = index; + + /* if this index is what the user requested, then register + * now (setup won't fail at this point). It's ok to just + * call register again if previously .setup failed. + */ + if (index == hvc_con_driver.index) + register_console(&hvc_con_driver); + + return 0; +} +EXPORT_SYMBOL(hvc_instantiate); /* Wake the sleeping khvcd */ static void hvc_kick(void) @@ -125,13 +289,17 @@ static void hvc_kick(void) wake_up_process(hvc_task); } +static int hvc_poll(struct hvc_struct *hp); + /* * NOTE: This API isn't used if the console adapter doesn't support interrupts. * In this case the console is poll driven. */ static irqreturn_t hvc_handle_interrupt(int irq, void *dev_instance, struct pt_regs *regs) { - hvc_kick(); + /* if hvc_poll request a repoll, then kick the hvcd thread */ + if (hvc_poll(dev_instance)) + hvc_kick(); return IRQ_HANDLED; } @@ -141,34 +309,6 @@ static void hvc_unthrottle(struct tty_struct *tty) } /* - * Do not call this function with either the hvc_strucst_lock or the hvc_struct - * lock held. If successful, this function increments the kobject reference - * count against the target hvc_struct so it should be released when finished. - */ -struct hvc_struct *hvc_get_by_index(int index) -{ - struct hvc_struct *hp; - unsigned long flags; - - spin_lock(&hvc_structs_lock); - - list_for_each_entry(hp, &hvc_structs, next) { - spin_lock_irqsave(&hp->lock, flags); - if (hp->index == index) { - kobject_get(&hp->kobj); - spin_unlock_irqrestore(&hp->lock, flags); - spin_unlock(&hvc_structs_lock); - return hp; - } - spin_unlock_irqrestore(&hp->lock, flags); - } - hp = NULL; - - spin_unlock(&hvc_structs_lock); - return hp; -} - -/* * The TTY interface won't be used until after the vio layer has exposed the vty * adapter to the kernel. */ @@ -329,7 +469,7 @@ static void hvc_push(struct hvc_struct *hp) { int n; - n = hvc_put_chars(hp->vtermno, hp->outbuf, hp->n_outbuf); + n = hp->ops->put_chars(hp->vtermno, hp->outbuf, hp->n_outbuf); if (n <= 0) { if (n == 0) return; @@ -467,7 +607,7 @@ static int hvc_poll(struct hvc_struct *hp) break; } - n = hvc_get_chars(hp->vtermno, buf, count); + n = hp->ops->get_chars(hp->vtermno, buf, count); if (n <= 0) { /* Hangup the tty when disconnected from host */ if (n == -EPIPE) { @@ -479,14 +619,17 @@ static int hvc_poll(struct hvc_struct *hp) } for (i = 0; i < n; ++i) { #ifdef CONFIG_MAGIC_SYSRQ - /* Handle the SysRq Hack */ - if (buf[i] == '\x0f') { /* ^O -- should support a sequence */ - sysrq_pressed = 1; - continue; - } else if (sysrq_pressed) { - handle_sysrq(buf[i], NULL, tty); - sysrq_pressed = 0; - continue; + if (hp->index == hvc_con_driver.index) { + /* Handle the SysRq Hack */ + /* XXX should support a sequence */ + if (buf[i] == '\x0f') { /* ^O */ + sysrq_pressed = 1; + continue; + } else if (sysrq_pressed) { + handle_sysrq(buf[i], NULL, tty); + sysrq_pressed = 0; + continue; + } } #endif /* CONFIG_MAGIC_SYSRQ */ tty_insert_flip_char(tty, buf[i], 0); @@ -497,8 +640,8 @@ static int hvc_poll(struct hvc_struct *hp) /* * Account for the total amount read in one loop, and if above - * 64 bytes, we do a quick schedule loop to let the tty grok the - * data and eventually throttle us. + * 64 bytes, we do a quick schedule loop to let the tty grok + * the data and eventually throttle us. */ read_total += n; if (read_total >= 64) { @@ -542,7 +685,6 @@ int khvcd(void *unused) if (cpus_empty(cpus_in_xmon)) { spin_lock(&hvc_structs_lock); list_for_each_entry(hp, &hvc_structs, next) { - /*hp = list_entry(node, struct hvc_struct, * next); */ poll_mask |= hvc_poll(hp); } spin_unlock(&hvc_structs_lock); @@ -577,14 +719,6 @@ static struct tty_operations hvc_ops = { .chars_in_buffer = hvc_chars_in_buffer, }; -char hvc_driver_name[] = "hvc_console"; - -static struct vio_device_id hvc_driver_table[] __devinitdata= { - {"serial", "hvterm1"}, - { NULL, } -}; -MODULE_DEVICE_TABLE(vio, hvc_driver_table); - /* callback when the kboject ref count reaches zero. */ static void destroy_hvc_struct(struct kobject *kobj) { @@ -606,41 +740,51 @@ static struct kobj_type hvc_kobj_type = { .release = destroy_hvc_struct, }; -static int __devinit hvc_probe( - struct vio_dev *dev, - const struct vio_device_id *id) +struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int irq, + struct hv_ops *ops) { struct hvc_struct *hp; - - /* probed with invalid parameters. */ - if (!dev || !id) - return -EPERM; + int i; hp = kmalloc(sizeof(*hp), GFP_KERNEL); if (!hp) - return -ENOMEM; + return ERR_PTR(-ENOMEM); memset(hp, 0x00, sizeof(*hp)); - hp->vtermno = dev->unit_address; - hp->vdev = dev; - hp->vdev->dev.driver_data = hp; - hp->irq = dev->irq; + + hp->vtermno = vtermno; + hp->irq = irq; + hp->ops = ops; kobject_init(&hp->kobj); hp->kobj.ktype = &hvc_kobj_type; spin_lock_init(&hp->lock); spin_lock(&hvc_structs_lock); - hp->index = ++hvc_count; + + /* + * find index to use: + * see if this vterm id matches one registered for console. + */ + for (i=0; i < MAX_NR_HVC_CONSOLES; i++) + if (vtermnos[i] == hp->vtermno) + break; + + /* no matching slot, just use a counter */ + if (i >= MAX_NR_HVC_CONSOLES) + i = ++last_hvc; + + hp->index = i; + list_add_tail(&(hp->next), &hvc_structs); spin_unlock(&hvc_structs_lock); - return 0; + return hp; } +EXPORT_SYMBOL(hvc_alloc); -static int __devexit hvc_remove(struct vio_dev *dev) +int __devexit hvc_remove(struct hvc_struct *hp) { - struct hvc_struct *hp = dev->dev.driver_data; unsigned long flags; struct kobject *kobjp; struct tty_struct *tty; @@ -673,23 +817,14 @@ static int __devexit hvc_remove(struct vio_dev *dev) tty_hangup(tty); return 0; } - -static struct vio_driver hvc_vio_driver = { - .name = hvc_driver_name, - .id_table = hvc_driver_table, - .probe = hvc_probe, - .remove = hvc_remove, -}; +EXPORT_SYMBOL(hvc_remove); /* Driver initialization. Follow console initialization. This is where the TTY * interfaces start to become available. */ int __init hvc_init(void) { - int rc; - - /* We need more than num_vterms adapters due to hotplug additions. */ + /* We need more than hvc_count adapters due to hotplug additions. */ hvc_driver = alloc_tty_driver(HVC_ALLOC_TTY_ADAPTERS); - /* hvc_driver = alloc_tty_driver(num_vterms); */ if (!hvc_driver) return -ENOMEM; @@ -716,116 +851,20 @@ int __init hvc_init(void) return -EIO; } - /* Register as a vio device to receive callbacks */ - rc = vio_register_driver(&hvc_vio_driver); - - return rc; + return 0; } +module_init(hvc_init); -/* This isn't particularily necessary due to this being a console driver but it - * is nice to be thorough */ +/* This isn't particularily necessary due to this being a console driver + * but it is nice to be thorough. + */ static void __exit hvc_exit(void) { kthread_stop(hvc_task); - vio_unregister_driver(&hvc_vio_driver); tty_unregister_driver(hvc_driver); /* return tty_struct instances allocated in hvc_init(). */ put_tty_driver(hvc_driver); + unregister_console(&hvc_con_driver); } - -/* - * Console APIs, NOT TTY. These APIs are available immediately when - * hvc_console_setup() finds adapters. - */ - -/* - * hvc_instantiate() is an early console discovery method which locates consoles - * prior to the vio subsystem discovering them. Hotplugged vty adapters do NOT - * get an hvc_instantiate() callback since the appear after early console init. - */ -int hvc_instantiate(uint32_t vtermno, int index) -{ - if (index < 0 || index >= MAX_NR_HVC_CONSOLES) - return -1; - - if (vtermnos[index] != -1) - return -1; - - vtermnos[index] = vtermno; - return 0; -} - -void hvc_console_print(struct console *co, const char *b, unsigned count) -{ - char c[16] __ALIGNED__; - unsigned i = 0, n = 0; - int r, donecr = 0; - - /* Console access attempt outside of acceptable console range. */ - if (co->index >= MAX_NR_HVC_CONSOLES) - return; - - /* This console adapter was removed so it is not useable. */ - if (vtermnos[co->index] < 0) - return; - - while (count > 0 || i > 0) { - if (count > 0 && i < sizeof(c)) { - if (b[n] == '\n' && !donecr) { - c[i++] = '\r'; - donecr = 1; - } else { - c[i++] = b[n++]; - donecr = 0; - --count; - } - } else { - r = hvc_put_chars(vtermnos[co->index], c, i); - if (r < 0) { - /* throw away chars on error */ - i = 0; - } else if (r > 0) { - i -= r; - if (i > 0) - memmove(c, c+r, i); - } - } - } -} - -static struct tty_driver *hvc_console_device(struct console *c, int *index) -{ - *index = c->index; - return hvc_driver; -} - -static int __init hvc_console_setup(struct console *co, char *options) -{ - return 0; -} - -struct console hvc_con_driver = { - .name = "hvc", - .write = hvc_console_print, - .device = hvc_console_device, - .setup = hvc_console_setup, - .flags = CON_PRINTBUFFER, - .index = -1, -}; - -/* Early console initialization. Preceeds driver initialization. */ -static int __init hvc_console_init(void) -{ - int i; - - for (i=0; i<MAX_NR_HVC_CONSOLES; i++) - vtermnos[i] = -1; - num_vterms = hvc_find_vtys(); - register_console(&hvc_con_driver); - return 0; -} -console_initcall(hvc_console_init); - -module_init(hvc_init); module_exit(hvc_exit); |