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Diffstat (limited to 'drivers/char/hvc_console.c')
-rw-r--r--drivers/char/hvc_console.c429
1 files changed, 234 insertions, 195 deletions
diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c
index 88cd858f74d0..cddb789902db 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);