From: Ryan S. Arnold Date: Mon, 27 Mar 2006 19:25:16 +0000 (+0200) Subject: [PATCH] powerpc: hvc_console updates X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=45d607ed92695d7543f5e1fc5b133cd69834e3e4;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git [PATCH] powerpc: hvc_console updates 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" Signed-off-by: Arnd Bergmann Signed-off-by: Paul Mackerras --- diff --git a/arch/powerpc/platforms/pseries/hvconsole.c b/arch/powerpc/platforms/pseries/hvconsole.c index 138e128a3886..ba6befd96636 100644 --- a/arch/powerpc/platforms/pseries/hvconsole.c +++ b/arch/powerpc/platforms/pseries/hvconsole.c @@ -62,6 +62,11 @@ int hvc_put_chars(uint32_t vtermno, const char *buf, int count) unsigned long *lbuf = (unsigned long *) buf; long ret; + + /* hcall will ret H_PARAMETER if 'count' exceeds firmware max.*/ + if (count > MAX_VIO_PUT_CHARS) + count = MAX_VIO_PUT_CHARS; + ret = plpar_hcall_norets(H_PUT_TERM_CHAR, vtermno, count, lbuf[0], lbuf[1]); if (ret == H_Success) diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig index facc3f1d9e37..831419381cf5 100644 --- a/drivers/char/Kconfig +++ b/drivers/char/Kconfig @@ -561,9 +561,19 @@ config TIPAR If unsure, say N. +config HVC_DRIVER + bool + help + Users of pSeries machines that want to utilize the hvc console front-end + module for their backend console driver should select this option. + It will automatically be selected if one of the back-end console drivers + is selected. + + config HVC_CONSOLE bool "pSeries Hypervisor Virtual Console support" depends on PPC_PSERIES + select HVC_DRIVER help pSeries machines when partitioned support a hypervisor virtual console. This driver allows each pSeries partition to have a console diff --git a/drivers/char/Makefile b/drivers/char/Makefile index b2a11245fa95..e6c03335fd6a 100644 --- a/drivers/char/Makefile +++ b/drivers/char/Makefile @@ -41,7 +41,8 @@ obj-$(CONFIG_N_HDLC) += n_hdlc.o obj-$(CONFIG_AMIGA_BUILTIN_SERIAL) += amiserial.o obj-$(CONFIG_SX) += sx.o generic_serial.o obj-$(CONFIG_RIO) += rio/ generic_serial.o -obj-$(CONFIG_HVC_CONSOLE) += hvc_console.o hvc_vio.o hvsi.o +obj-$(CONFIG_HVC_DRIVER) += hvc_console.o +obj-$(CONFIG_HVC_CONSOLE) += hvc_vio.o hvsi.o obj-$(CONFIG_RAW_DRIVER) += raw.o obj-$(CONFIG_SGI_SNSC) += snsc.o snsc_event.o obj-$(CONFIG_MMTIMER) += mmtimer.o diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c index a94c5b0cac52..2b6a56b2bf35 100644 --- a/drivers/char/hvc_console.c +++ b/drivers/char/hvc_console.c @@ -39,8 +39,10 @@ #include #include #include + #include -#include + +#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 */ diff --git a/drivers/char/hvc_console.h b/drivers/char/hvc_console.h new file mode 100644 index 000000000000..96b7401319c1 --- /dev/null +++ b/drivers/char/hvc_console.h @@ -0,0 +1,63 @@ +/* + * hvc_console.h + * Copyright (C) 2005 IBM Corporation + * + * Author(s): + * Ryan S. Arnold + * + * hvc_console header information: + * moved here from include/asm-powerpc/hvconsole.h + * and drivers/char/hvc_console.c + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef HVC_CONSOLE_H +#define HVC_CONSOLE_H + +/* + * This is the max number of console adapters that can/will be found as + * console devices on first stage console init. Any number beyond this range + * can't be used as a console device but is still a valid tty device. + */ +#define MAX_NR_HVC_CONSOLES 16 + +/* + * 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. + */ +#define HVC_ALLOC_TTY_ADAPTERS 8 + + +/* implemented by a low level driver */ +struct hv_ops { + int (*get_chars)(uint32_t vtermno, char *buf, int count); + int (*put_chars)(uint32_t vtermno, const char *buf, int count); +}; + +struct hvc_struct; + +/* Register a vterm and a slot index for use as a console (console_init) */ +extern int hvc_instantiate(uint32_t vtermno, int index, struct hv_ops *ops); + +/* register a vterm for hvc tty operation (module_init or hotplug add) */ +extern struct hvc_struct * __devinit hvc_alloc(uint32_t vtermno, int irq, + struct hv_ops *ops); +/* remove a vterm from hvc tty operation (modele_exit or hotplug remove) */ +extern int __devexit hvc_remove(struct hvc_struct *hp); + +#endif // HVC_CONSOLE_H diff --git a/drivers/char/hvc_vio.c b/drivers/char/hvc_vio.c index f5212eb2b41d..9add81ceb440 100644 --- a/drivers/char/hvc_vio.c +++ b/drivers/char/hvc_vio.c @@ -31,10 +31,13 @@ #include #include + #include #include #include +#include "hvc_console.h" + char hvc_driver_name[] = "hvc_console"; static struct vio_device_id hvc_driver_table[] __devinitdata = { @@ -48,6 +51,14 @@ static int filtered_get_chars(uint32_t vtermno, char *buf, int count) unsigned long got; int i; + /* + * Vio firmware will read up to SIZE_VIO_GET_CHARS at its own discretion + * so we play safe and avoid the situation where got > count which could + * overload the flip buffer. + */ + if (count < SIZE_VIO_GET_CHARS) + return -EAGAIN; + got = hvc_get_chars(vtermno, buf, count); /* diff --git a/include/asm-powerpc/hvconsole.h b/include/asm-powerpc/hvconsole.h index 34daf7b9b62f..35ea69e8121f 100644 --- a/include/asm-powerpc/hvconsole.h +++ b/include/asm-powerpc/hvconsole.h @@ -24,28 +24,18 @@ #ifdef __KERNEL__ /* - * This is the max number of console adapters that can/will be found as - * console devices on first stage console init. Any number beyond this range - * can't be used as a console device but is still a valid tty device. + * PSeries firmware will only send/recv up to 16 bytes of character data per + * hcall. */ -#define MAX_NR_HVC_CONSOLES 16 +#define MAX_VIO_PUT_CHARS 16 +#define SIZE_VIO_GET_CHARS 16 -/* implemented by a low level driver */ -struct hv_ops { - int (*get_chars)(uint32_t vtermno, char *buf, int count); - int (*put_chars)(uint32_t vtermno, const char *buf, int count); -}; +/* + * Vio firmware always attempts to fetch MAX_VIO_GET_CHARS chars. The 'count' + * parm is included to conform to put_chars() function pointer template + */ extern int hvc_get_chars(uint32_t vtermno, char *buf, int count); extern int hvc_put_chars(uint32_t vtermno, const char *buf, int count); -struct hvc_struct; - -/* Register a vterm and a slot index for use as a console (console_init) */ -extern int hvc_instantiate(uint32_t vtermno, int index, struct hv_ops *ops); -/* register a vterm for hvc tty operation (module_init or hotplug add) */ -extern struct hvc_struct * __devinit hvc_alloc(uint32_t vtermno, int irq, - struct hv_ops *ops); -/* remove a vterm from hvc tty operation (modele_exit or hotplug remove) */ -extern int __devexit hvc_remove(struct hvc_struct *hp); #endif /* __KERNEL__ */ #endif /* _PPC64_HVCONSOLE_H */