diff options
Diffstat (limited to 'drivers/s390/cio/cio.c')
-rw-r--r-- | drivers/s390/cio/cio.c | 860 |
1 files changed, 860 insertions, 0 deletions
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c new file mode 100644 index 00000000000..99ce5a56798 --- /dev/null +++ b/drivers/s390/cio/cio.c @@ -0,0 +1,860 @@ +/* + * drivers/s390/cio/cio.c + * S/390 common I/O routines -- low level i/o calls + * $Revision: 1.131 $ + * + * Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH, + * IBM Corporation + * Author(s): Ingo Adlung (adlung@de.ibm.com) + * Cornelia Huck (cohuck@de.ibm.com) + * Arnd Bergmann (arndb@de.ibm.com) + * Martin Schwidefsky (schwidefsky@de.ibm.com) + */ + +#include <linux/module.h> +#include <linux/config.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/device.h> +#include <linux/kernel_stat.h> +#include <linux/interrupt.h> + +#include <asm/cio.h> +#include <asm/delay.h> +#include <asm/irq.h> + +#include "airq.h" +#include "cio.h" +#include "css.h" +#include "chsc.h" +#include "ioasm.h" +#include "blacklist.h" +#include "cio_debug.h" + +debug_info_t *cio_debug_msg_id; +debug_info_t *cio_debug_trace_id; +debug_info_t *cio_debug_crw_id; + +int cio_show_msg; + +static int __init +cio_setup (char *parm) +{ + if (!strcmp (parm, "yes")) + cio_show_msg = 1; + else if (!strcmp (parm, "no")) + cio_show_msg = 0; + else + printk (KERN_ERR "cio_setup : invalid cio_msg parameter '%s'", + parm); + return 1; +} + +__setup ("cio_msg=", cio_setup); + +/* + * Function: cio_debug_init + * Initializes three debug logs (under /proc/s390dbf) for common I/O: + * - cio_msg logs the messages which are printk'ed when CONFIG_DEBUG_IO is on + * - cio_trace logs the calling of different functions + * - cio_crw logs the messages which are printk'ed when CONFIG_DEBUG_CRW is on + * debug levels depend on CONFIG_DEBUG_IO resp. CONFIG_DEBUG_CRW + */ +static int __init +cio_debug_init (void) +{ + cio_debug_msg_id = debug_register ("cio_msg", 4, 4, 16*sizeof (long)); + if (!cio_debug_msg_id) + goto out_unregister; + debug_register_view (cio_debug_msg_id, &debug_sprintf_view); + debug_set_level (cio_debug_msg_id, 2); + cio_debug_trace_id = debug_register ("cio_trace", 4, 4, 8); + if (!cio_debug_trace_id) + goto out_unregister; + debug_register_view (cio_debug_trace_id, &debug_hex_ascii_view); + debug_set_level (cio_debug_trace_id, 2); + cio_debug_crw_id = debug_register ("cio_crw", 2, 4, 16*sizeof (long)); + if (!cio_debug_crw_id) + goto out_unregister; + debug_register_view (cio_debug_crw_id, &debug_sprintf_view); + debug_set_level (cio_debug_crw_id, 2); + pr_debug("debugging initialized\n"); + return 0; + +out_unregister: + if (cio_debug_msg_id) + debug_unregister (cio_debug_msg_id); + if (cio_debug_trace_id) + debug_unregister (cio_debug_trace_id); + if (cio_debug_crw_id) + debug_unregister (cio_debug_crw_id); + pr_debug("could not initialize debugging\n"); + return -1; +} + +arch_initcall (cio_debug_init); + +int +cio_set_options (struct subchannel *sch, int flags) +{ + sch->options.suspend = (flags & DOIO_ALLOW_SUSPEND) != 0; + sch->options.prefetch = (flags & DOIO_DENY_PREFETCH) != 0; + sch->options.inter = (flags & DOIO_SUPPRESS_INTER) != 0; + return 0; +} + +/* FIXME: who wants to use this? */ +int +cio_get_options (struct subchannel *sch) +{ + int flags; + + flags = 0; + if (sch->options.suspend) + flags |= DOIO_ALLOW_SUSPEND; + if (sch->options.prefetch) + flags |= DOIO_DENY_PREFETCH; + if (sch->options.inter) + flags |= DOIO_SUPPRESS_INTER; + return flags; +} + +/* + * Use tpi to get a pending interrupt, call the interrupt handler and + * return a pointer to the subchannel structure. + */ +static inline int +cio_tpi(void) +{ + struct tpi_info *tpi_info; + struct subchannel *sch; + struct irb *irb; + + tpi_info = (struct tpi_info *) __LC_SUBCHANNEL_ID; + if (tpi (NULL) != 1) + return 0; + irb = (struct irb *) __LC_IRB; + /* Store interrupt response block to lowcore. */ + if (tsch (tpi_info->irq, irb) != 0) + /* Not status pending or not operational. */ + return 1; + sch = (struct subchannel *)(unsigned long)tpi_info->intparm; + if (!sch) + return 1; + local_bh_disable(); + irq_enter (); + spin_lock(&sch->lock); + memcpy (&sch->schib.scsw, &irb->scsw, sizeof (struct scsw)); + if (sch->driver && sch->driver->irq) + sch->driver->irq(&sch->dev); + spin_unlock(&sch->lock); + irq_exit (); + __local_bh_enable(); + return 1; +} + +static inline int +cio_start_handle_notoper(struct subchannel *sch, __u8 lpm) +{ + char dbf_text[15]; + + if (lpm != 0) + sch->lpm &= ~lpm; + else + sch->lpm = 0; + + stsch (sch->irq, &sch->schib); + + CIO_MSG_EVENT(0, "cio_start: 'not oper' status for " + "subchannel %04x!\n", sch->irq); + sprintf(dbf_text, "no%s", sch->dev.bus_id); + CIO_TRACE_EVENT(0, dbf_text); + CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib)); + + return (sch->lpm ? -EACCES : -ENODEV); +} + +int +cio_start_key (struct subchannel *sch, /* subchannel structure */ + struct ccw1 * cpa, /* logical channel prog addr */ + __u8 lpm, /* logical path mask */ + __u8 key) /* storage key */ +{ + char dbf_txt[15]; + int ccode; + + CIO_TRACE_EVENT (4, "stIO"); + CIO_TRACE_EVENT (4, sch->dev.bus_id); + + /* sch is always under 2G. */ + sch->orb.intparm = (__u32)(unsigned long)sch; + sch->orb.fmt = 1; + + sch->orb.pfch = sch->options.prefetch == 0; + sch->orb.spnd = sch->options.suspend; + sch->orb.ssic = sch->options.suspend && sch->options.inter; + sch->orb.lpm = (lpm != 0) ? (lpm & sch->opm) : sch->lpm; +#ifdef CONFIG_ARCH_S390X + /* + * for 64 bit we always support 64 bit IDAWs with 4k page size only + */ + sch->orb.c64 = 1; + sch->orb.i2k = 0; +#endif + sch->orb.key = key >> 4; + /* issue "Start Subchannel" */ + sch->orb.cpa = (__u32) __pa (cpa); + ccode = ssch (sch->irq, &sch->orb); + + /* process condition code */ + sprintf (dbf_txt, "ccode:%d", ccode); + CIO_TRACE_EVENT (4, dbf_txt); + + switch (ccode) { + case 0: + /* + * initialize device status information + */ + sch->schib.scsw.actl |= SCSW_ACTL_START_PEND; + return 0; + case 1: /* status pending */ + case 2: /* busy */ + return -EBUSY; + default: /* device/path not operational */ + return cio_start_handle_notoper(sch, lpm); + } +} + +int +cio_start (struct subchannel *sch, struct ccw1 *cpa, __u8 lpm) +{ + return cio_start_key(sch, cpa, lpm, default_storage_key); +} + +/* + * resume suspended I/O operation + */ +int +cio_resume (struct subchannel *sch) +{ + char dbf_txt[15]; + int ccode; + + CIO_TRACE_EVENT (4, "resIO"); + CIO_TRACE_EVENT (4, sch->dev.bus_id); + + ccode = rsch (sch->irq); + + sprintf (dbf_txt, "ccode:%d", ccode); + CIO_TRACE_EVENT (4, dbf_txt); + + switch (ccode) { + case 0: + sch->schib.scsw.actl |= SCSW_ACTL_RESUME_PEND; + return 0; + case 1: + return -EBUSY; + case 2: + return -EINVAL; + default: + /* + * useless to wait for request completion + * as device is no longer operational ! + */ + return -ENODEV; + } +} + +/* + * halt I/O operation + */ +int +cio_halt(struct subchannel *sch) +{ + char dbf_txt[15]; + int ccode; + + if (!sch) + return -ENODEV; + + CIO_TRACE_EVENT (2, "haltIO"); + CIO_TRACE_EVENT (2, sch->dev.bus_id); + + /* + * Issue "Halt subchannel" and process condition code + */ + ccode = hsch (sch->irq); + + sprintf (dbf_txt, "ccode:%d", ccode); + CIO_TRACE_EVENT (2, dbf_txt); + + switch (ccode) { + case 0: + sch->schib.scsw.actl |= SCSW_ACTL_HALT_PEND; + return 0; + case 1: /* status pending */ + case 2: /* busy */ + return -EBUSY; + default: /* device not operational */ + return -ENODEV; + } +} + +/* + * Clear I/O operation + */ +int +cio_clear(struct subchannel *sch) +{ + char dbf_txt[15]; + int ccode; + + if (!sch) + return -ENODEV; + + CIO_TRACE_EVENT (2, "clearIO"); + CIO_TRACE_EVENT (2, sch->dev.bus_id); + + /* + * Issue "Clear subchannel" and process condition code + */ + ccode = csch (sch->irq); + + sprintf (dbf_txt, "ccode:%d", ccode); + CIO_TRACE_EVENT (2, dbf_txt); + + switch (ccode) { + case 0: + sch->schib.scsw.actl |= SCSW_ACTL_CLEAR_PEND; + return 0; + default: /* device not operational */ + return -ENODEV; + } +} + +/* + * Function: cio_cancel + * Issues a "Cancel Subchannel" on the specified subchannel + * Note: We don't need any fancy intparms and flags here + * since xsch is executed synchronously. + * Only for common I/O internal use as for now. + */ +int +cio_cancel (struct subchannel *sch) +{ + char dbf_txt[15]; + int ccode; + + if (!sch) + return -ENODEV; + + CIO_TRACE_EVENT (2, "cancelIO"); + CIO_TRACE_EVENT (2, sch->dev.bus_id); + + ccode = xsch (sch->irq); + + sprintf (dbf_txt, "ccode:%d", ccode); + CIO_TRACE_EVENT (2, dbf_txt); + + switch (ccode) { + case 0: /* success */ + /* Update information in scsw. */ + stsch (sch->irq, &sch->schib); + return 0; + case 1: /* status pending */ + return -EBUSY; + case 2: /* not applicable */ + return -EINVAL; + default: /* not oper */ + return -ENODEV; + } +} + +/* + * Function: cio_modify + * Issues a "Modify Subchannel" on the specified subchannel + */ +int +cio_modify (struct subchannel *sch) +{ + int ccode, retry, ret; + + ret = 0; + for (retry = 0; retry < 5; retry++) { + ccode = msch_err (sch->irq, &sch->schib); + if (ccode < 0) /* -EIO if msch gets a program check. */ + return ccode; + switch (ccode) { + case 0: /* successfull */ + return 0; + case 1: /* status pending */ + return -EBUSY; + case 2: /* busy */ + udelay (100); /* allow for recovery */ + ret = -EBUSY; + break; + case 3: /* not operational */ + return -ENODEV; + } + } + return ret; +} + +/* + * Enable subchannel. + */ +int +cio_enable_subchannel (struct subchannel *sch, unsigned int isc) +{ + char dbf_txt[15]; + int ccode; + int retry; + int ret; + + CIO_TRACE_EVENT (2, "ensch"); + CIO_TRACE_EVENT (2, sch->dev.bus_id); + + ccode = stsch (sch->irq, &sch->schib); + if (ccode) + return -ENODEV; + + for (retry = 5, ret = 0; retry > 0; retry--) { + sch->schib.pmcw.ena = 1; + sch->schib.pmcw.isc = isc; + sch->schib.pmcw.intparm = (__u32)(unsigned long)sch; + ret = cio_modify(sch); + if (ret == -ENODEV) + break; + if (ret == -EIO) + /* + * Got a program check in cio_modify. Try without + * the concurrent sense bit the next time. + */ + sch->schib.pmcw.csense = 0; + if (ret == 0) { + stsch (sch->irq, &sch->schib); + if (sch->schib.pmcw.ena) + break; + } + if (ret == -EBUSY) { + struct irb irb; + if (tsch(sch->irq, &irb) != 0) + break; + } + } + sprintf (dbf_txt, "ret:%d", ret); + CIO_TRACE_EVENT (2, dbf_txt); + return ret; +} + +/* + * Disable subchannel. + */ +int +cio_disable_subchannel (struct subchannel *sch) +{ + char dbf_txt[15]; + int ccode; + int retry; + int ret; + + CIO_TRACE_EVENT (2, "dissch"); + CIO_TRACE_EVENT (2, sch->dev.bus_id); + + ccode = stsch (sch->irq, &sch->schib); + if (ccode == 3) /* Not operational. */ + return -ENODEV; + + if (sch->schib.scsw.actl != 0) + /* + * the disable function must not be called while there are + * requests pending for completion ! + */ + return -EBUSY; + + for (retry = 5, ret = 0; retry > 0; retry--) { + sch->schib.pmcw.ena = 0; + ret = cio_modify(sch); + if (ret == -ENODEV) + break; + if (ret == -EBUSY) + /* + * The subchannel is busy or status pending. + * We'll disable when the next interrupt was delivered + * via the state machine. + */ + break; + if (ret == 0) { + stsch (sch->irq, &sch->schib); + if (!sch->schib.pmcw.ena) + break; + } + } + sprintf (dbf_txt, "ret:%d", ret); + CIO_TRACE_EVENT (2, dbf_txt); + return ret; +} + +/* + * cio_validate_subchannel() + * + * Find out subchannel type and initialize struct subchannel. + * Return codes: + * SUBCHANNEL_TYPE_IO for a normal io subchannel + * SUBCHANNEL_TYPE_CHSC for a chsc subchannel + * SUBCHANNEL_TYPE_MESSAGE for a messaging subchannel + * SUBCHANNEL_TYPE_ADM for a adm(?) subchannel + * -ENXIO for non-defined subchannels + * -ENODEV for subchannels with invalid device number or blacklisted devices + */ +int +cio_validate_subchannel (struct subchannel *sch, unsigned int irq) +{ + char dbf_txt[15]; + int ccode; + + sprintf (dbf_txt, "valsch%x", irq); + CIO_TRACE_EVENT (4, dbf_txt); + + /* Nuke all fields. */ + memset(sch, 0, sizeof(struct subchannel)); + + spin_lock_init(&sch->lock); + + /* Set a name for the subchannel */ + snprintf (sch->dev.bus_id, BUS_ID_SIZE, "0.0.%04x", irq); + + /* + * The first subchannel that is not-operational (ccode==3) + * indicates that there aren't any more devices available. + */ + sch->irq = irq; + ccode = stsch (irq, &sch->schib); + if (ccode) + return -ENXIO; + + /* Copy subchannel type from path management control word. */ + sch->st = sch->schib.pmcw.st; + + /* + * ... just being curious we check for non I/O subchannels + */ + if (sch->st != 0) { + CIO_DEBUG(KERN_INFO, 0, + "Subchannel %04X reports " + "non-I/O subchannel type %04X\n", + sch->irq, sch->st); + /* We stop here for non-io subchannels. */ + return sch->st; + } + + /* Initialization for io subchannels. */ + if (!sch->schib.pmcw.dnv) + /* io subchannel but device number is invalid. */ + return -ENODEV; + + /* Devno is valid. */ + if (is_blacklisted (sch->schib.pmcw.dev)) { + /* + * This device must not be known to Linux. So we simply + * say that there is no device and return ENODEV. + */ + CIO_MSG_EVENT(0, "Blacklisted device detected " + "at devno %04X\n", sch->schib.pmcw.dev); + return -ENODEV; + } + sch->opm = 0xff; + chsc_validate_chpids(sch); + sch->lpm = sch->schib.pmcw.pim & + sch->schib.pmcw.pam & + sch->schib.pmcw.pom & + sch->opm; + + CIO_DEBUG(KERN_INFO, 0, + "Detected device %04X on subchannel %04X" + " - PIM = %02X, PAM = %02X, POM = %02X\n", + sch->schib.pmcw.dev, sch->irq, sch->schib.pmcw.pim, + sch->schib.pmcw.pam, sch->schib.pmcw.pom); + + /* + * We now have to initially ... + * ... set "interruption subclass" + * ... enable "concurrent sense" + * ... enable "multipath mode" if more than one + * CHPID is available. This is done regardless + * whether multiple paths are available for us. + */ + sch->schib.pmcw.isc = 3; /* could be smth. else */ + sch->schib.pmcw.csense = 1; /* concurrent sense */ + sch->schib.pmcw.ena = 0; + if ((sch->lpm & (sch->lpm - 1)) != 0) + sch->schib.pmcw.mp = 1; /* multipath mode */ + return 0; +} + +/* + * do_IRQ() handles all normal I/O device IRQ's (the special + * SMP cross-CPU interrupts have their own specific + * handlers). + * + */ +void +do_IRQ (struct pt_regs *regs) +{ + struct tpi_info *tpi_info; + struct subchannel *sch; + struct irb *irb; + + irq_enter (); + asm volatile ("mc 0,0"); + if (S390_lowcore.int_clock >= S390_lowcore.jiffy_timer) + /** + * Make sure that the i/o interrupt did not "overtake" + * the last HZ timer interrupt. + */ + account_ticks(regs); + /* + * Get interrupt information from lowcore + */ + tpi_info = (struct tpi_info *) __LC_SUBCHANNEL_ID; + irb = (struct irb *) __LC_IRB; + do { + kstat_cpu(smp_processor_id()).irqs[IO_INTERRUPT]++; + /* + * Non I/O-subchannel thin interrupts are processed differently + */ + if (tpi_info->adapter_IO == 1 && + tpi_info->int_type == IO_INTERRUPT_TYPE) { + do_adapter_IO(); + continue; + } + sch = (struct subchannel *)(unsigned long)tpi_info->intparm; + if (sch) + spin_lock(&sch->lock); + /* Store interrupt response block to lowcore. */ + if (tsch (tpi_info->irq, irb) == 0 && sch) { + /* Keep subchannel information word up to date. */ + memcpy (&sch->schib.scsw, &irb->scsw, + sizeof (irb->scsw)); + /* Call interrupt handler if there is one. */ + if (sch->driver && sch->driver->irq) + sch->driver->irq(&sch->dev); + } + if (sch) + spin_unlock(&sch->lock); + /* + * Are more interrupts pending? + * If so, the tpi instruction will update the lowcore + * to hold the info for the next interrupt. + * We don't do this for VM because a tpi drops the cpu + * out of the sie which costs more cycles than it saves. + */ + } while (!MACHINE_IS_VM && tpi (NULL) != 0); + irq_exit (); +} + +#ifdef CONFIG_CCW_CONSOLE +static struct subchannel console_subchannel; +static int console_subchannel_in_use; + +/* + * busy wait for the next interrupt on the console + */ +void +wait_cons_dev (void) +{ + unsigned long cr6 __attribute__ ((aligned (8))); + unsigned long save_cr6 __attribute__ ((aligned (8))); + + /* + * before entering the spinlock we may already have + * processed the interrupt on a different CPU... + */ + if (!console_subchannel_in_use) + return; + + /* disable all but isc 7 (console device) */ + __ctl_store (save_cr6, 6, 6); + cr6 = 0x01000000; + __ctl_load (cr6, 6, 6); + + do { + spin_unlock(&console_subchannel.lock); + if (!cio_tpi()) + cpu_relax(); + spin_lock(&console_subchannel.lock); + } while (console_subchannel.schib.scsw.actl != 0); + /* + * restore previous isc value + */ + __ctl_load (save_cr6, 6, 6); +} + +static int +cio_console_irq(void) +{ + int irq; + + if (console_irq != -1) { + /* VM provided us with the irq number of the console. */ + if (stsch(console_irq, &console_subchannel.schib) != 0 || + !console_subchannel.schib.pmcw.dnv) + return -1; + console_devno = console_subchannel.schib.pmcw.dev; + } else if (console_devno != -1) { + /* At least the console device number is known. */ + for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) { + if (stsch(irq, &console_subchannel.schib) != 0) + break; + if (console_subchannel.schib.pmcw.dnv && + console_subchannel.schib.pmcw.dev == + console_devno) { + console_irq = irq; + break; + } + } + if (console_irq == -1) + return -1; + } else { + /* unlike in 2.4, we cannot autoprobe here, since + * the channel subsystem is not fully initialized. + * With some luck, the HWC console can take over */ + printk(KERN_WARNING "No ccw console found!\n"); + return -1; + } + return console_irq; +} + +struct subchannel * +cio_probe_console(void) +{ + int irq, ret; + + if (xchg(&console_subchannel_in_use, 1) != 0) + return ERR_PTR(-EBUSY); + irq = cio_console_irq(); + if (irq == -1) { + console_subchannel_in_use = 0; + return ERR_PTR(-ENODEV); + } + memset(&console_subchannel, 0, sizeof(struct subchannel)); + ret = cio_validate_subchannel(&console_subchannel, irq); + if (ret) { + console_subchannel_in_use = 0; + return ERR_PTR(-ENODEV); + } + + /* + * enable console I/O-interrupt subclass 7 + */ + ctl_set_bit(6, 24); + console_subchannel.schib.pmcw.isc = 7; + console_subchannel.schib.pmcw.intparm = + (__u32)(unsigned long)&console_subchannel; + ret = cio_modify(&console_subchannel); + if (ret) { + console_subchannel_in_use = 0; + return ERR_PTR(ret); + } + return &console_subchannel; +} + +void +cio_release_console(void) +{ + console_subchannel.schib.pmcw.intparm = 0; + cio_modify(&console_subchannel); + ctl_clear_bit(6, 24); + console_subchannel_in_use = 0; +} + +/* Bah... hack to catch console special sausages. */ +int +cio_is_console(int irq) +{ + if (!console_subchannel_in_use) + return 0; + return (irq == console_subchannel.irq); +} + +struct subchannel * +cio_get_console_subchannel(void) +{ + if (!console_subchannel_in_use) + return 0; + return &console_subchannel; +} + +#endif +static inline int +__disable_subchannel_easy(unsigned int schid, struct schib *schib) +{ + int retry, cc; + + cc = 0; + for (retry=0;retry<3;retry++) { + schib->pmcw.ena = 0; + cc = msch(schid, schib); + if (cc) + return (cc==3?-ENODEV:-EBUSY); + stsch(schid, schib); + if (!schib->pmcw.ena) + return 0; + } + return -EBUSY; /* uhm... */ +} + +static inline int +__clear_subchannel_easy(unsigned int schid) +{ + int retry; + + if (csch(schid)) + return -ENODEV; + for (retry=0;retry<20;retry++) { + struct tpi_info ti; + + if (tpi(&ti)) { + tsch(schid, (struct irb *)__LC_IRB); + return 0; + } + udelay(100); + } + return -EBUSY; +} + +extern void do_reipl(unsigned long devno); + +/* Clear all subchannels. */ +void +clear_all_subchannels(void) +{ + unsigned int schid; + + local_irq_disable(); + for (schid=0;schid<=highest_subchannel;schid++) { + struct schib schib; + if (stsch(schid, &schib)) + break; /* break out of the loop */ + if (!schib.pmcw.ena) + continue; + switch(__disable_subchannel_easy(schid, &schib)) { + case 0: + case -ENODEV: + break; + default: /* -EBUSY */ + if (__clear_subchannel_easy(schid)) + break; /* give up... jump out of switch */ + stsch(schid, &schib); + __disable_subchannel_easy(schid, &schib); + } + } +} + +/* Make sure all subchannels are quiet before we re-ipl an lpar. */ +void +reipl(unsigned long devno) +{ + clear_all_subchannels(); + do_reipl(devno); +} |