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[PATCH] powerpc: hvc_console updates

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These are some updates from both Ryan and Arnd for the hvc_console
driver:

The main point is to enable the inclusion of a console driver
for rtas, which is currrently needed for the cell platform.

Also shuffle around some data-type declarations and moves some
functions out of include/asm-ppc64/hvconsole.h and into a new
drivers/char/hvc_console.h file.

Signed-off-by: "Ryan S. Arnold" <rsa@us.ibm.com>
Signed-off-by: Arnd Bergmann <abergman@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Ryan S. Arnold
2006-03-27 21:25:16 +02:00
committed by Paul Mackerras
parent 11089f08d9
commit 45d607ed92
7 changed files with 128 additions and 59 deletions
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69
drivers/char/hvc_console.c
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@@ -39,8 +39,10 @@
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <asm/uaccess.h>
#include <asm/hvconsole.h>
#include "hvc_console.h"
#define HVC_MAJOR 229
#define HVC_MINOR 0
@@ -54,17 +56,14 @@
#define HVC_CLOSE_WAIT (HZ/100) /* 1/10 of a second */
/*
* The Linux TTY code does not support dynamic addition of tty derived devices
* so we need to know how many tty devices we might need when space is allocated
* for the tty device. Since this driver supports hotplug of vty adapters we
* need to make sure we have enough allocated.
* These sizes are most efficient for vio, because they are the
* native transfer size. We could make them selectable in the
* future to better deal with backends that want other buffer sizes.
*/
#define HVC_ALLOC_TTY_ADAPTERS 8
#define N_OUTBUF 16
#define N_INBUF 16
#define __ALIGNED__ __attribute__((__aligned__(8)))
#define __ALIGNED__ __attribute__((__aligned__(sizeof(long))))
static struct tty_driver *hvc_driver;
static struct task_struct *hvc_task;
@@ -154,7 +153,7 @@ static uint32_t vtermnos[MAX_NR_HVC_CONSOLES] =
void hvc_console_print(struct console *co, const char *b, unsigned count)
{
char c[16] __ALIGNED__;
char c[N_OUTBUF] __ALIGNED__;
unsigned i = 0, n = 0;
int r, donecr = 0, index = co->index;
@@ -473,8 +472,10 @@ static void hvc_push(struct hvc_struct *hp)
n = hp->ops->put_chars(hp->vtermno, hp->outbuf, hp->n_outbuf);
if (n <= 0) {
if (n == 0)
if (n == 0) {
hp->do_wakeup = 1;
return;
}
/* throw away output on error; this happens when
there is no session connected to the vterm. */
hp->n_outbuf = 0;
@@ -486,12 +487,19 @@ static void hvc_push(struct hvc_struct *hp)
hp->do_wakeup = 1;
}
static inline int __hvc_write_kernel(struct hvc_struct *hp,
const unsigned char *buf, int count)
static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count)
{
struct hvc_struct *hp = tty->driver_data;
unsigned long flags;
int rsize, written = 0;
/* This write was probably executed during a tty close. */
if (!hp)
return -EPIPE;
if (hp->count <= 0)
return -EIO;
spin_lock_irqsave(&hp->lock, flags);
/* Push pending writes */
@@ -510,26 +518,8 @@ static inline int __hvc_write_kernel(struct hvc_struct *hp,
}
spin_unlock_irqrestore(&hp->lock, flags);
return written;
}
static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count)
{
struct hvc_struct *hp = tty->driver_data;
int written;
/* This write was probably executed during a tty close. */
if (!hp)
return -EPIPE;
if (hp->count <= 0)
return -EIO;
written = __hvc_write_kernel(hp, buf, count);
/*
* Racy, but harmless, kick thread if there is still pending data.
* There really is nothing wrong with kicking the thread, even if there
* is no buffered data.
*/
if (hp->n_outbuf)
hvc_kick();
@@ -614,6 +604,13 @@ static int hvc_poll(struct hvc_struct *hp)
spin_unlock_irqrestore(&hp->lock, flags);
tty_hangup(tty);
spin_lock_irqsave(&hp->lock, flags);
} else if ( n == -EAGAIN ) {
/*
* Some back-ends can only ensure a certain min
* num of bytes read, which may be > 'count'.
* Let the tty clear the flip buff to make room.
*/
poll_mask |= HVC_POLL_READ;
}
break;
}
@@ -635,16 +632,7 @@ static int hvc_poll(struct hvc_struct *hp)
tty_insert_flip_char(tty, buf[i], 0);
}
/*
* 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.
*/
read_total += n;
if (read_total >= 64) {
poll_mask |= HVC_POLL_QUICK;
break;
}
}
throttled:
/* Wakeup write queue if necessary */
@@ -767,7 +755,8 @@ struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int irq,
* see if this vterm id matches one registered for console.
*/
for (i=0; i < MAX_NR_HVC_CONSOLES; i++)
if (vtermnos[i] == hp->vtermno)
if (vtermnos[i] == hp->vtermno &&
cons_ops[i] == hp->ops)
break;
/* no matching slot, just use a counter */