diff options
Diffstat (limited to 'drivers/s390/cio/cio.c')
| -rw-r--r-- | drivers/s390/cio/cio.c | 1151 |
1 files changed, 1151 insertions, 0 deletions
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c new file mode 100644 index 00000000..a49c46c9 --- /dev/null +++ b/drivers/s390/cio/cio.c @@ -0,0 +1,1151 @@ +/* + * drivers/s390/cio/cio.c + * S/390 common I/O routines -- low level i/o calls + * + * Copyright IBM Corp. 1999,2008 + * Author(s): Ingo Adlung (adlung@de.ibm.com) + * Cornelia Huck (cornelia.huck@de.ibm.com) + * Arnd Bergmann (arndb@de.ibm.com) + * Martin Schwidefsky (schwidefsky@de.ibm.com) + */ + +#define KMSG_COMPONENT "cio" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + +#include <linux/ftrace.h> +#include <linux/module.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 <asm/irq_regs.h> +#include <asm/setup.h> +#include <asm/reset.h> +#include <asm/ipl.h> +#include <asm/chpid.h> +#include <asm/airq.h> +#include <asm/isc.h> +#include <asm/cputime.h> +#include <asm/fcx.h> +#include <asm/nmi.h> +#include <asm/crw.h> +#include "cio.h" +#include "css.h" +#include "chsc.h" +#include "ioasm.h" +#include "io_sch.h" +#include "blacklist.h" +#include "cio_debug.h" +#include "chp.h" + +debug_info_t *cio_debug_msg_id; +debug_info_t *cio_debug_trace_id; +debug_info_t *cio_debug_crw_id; + +/* + * Function: cio_debug_init + * Initializes three debug logs for common I/O: + * - cio_msg logs generic cio messages + * - cio_trace logs the calling of different functions + * - cio_crw logs machine check related cio messages + */ +static int __init cio_debug_init(void) +{ + cio_debug_msg_id = debug_register("cio_msg", 16, 1, 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", 16, 1, 16); + 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", 16, 1, 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, 4); + 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); + return -1; +} + +arch_initcall (cio_debug_init); + +int cio_set_options(struct subchannel *sch, int flags) +{ + struct io_subchannel_private *priv = to_io_private(sch); + + priv->options.suspend = (flags & DOIO_ALLOW_SUSPEND) != 0; + priv->options.prefetch = (flags & DOIO_DENY_PREFETCH) != 0; + priv->options.inter = (flags & DOIO_SUPPRESS_INTER) != 0; + return 0; +} + +static int +cio_start_handle_notoper(struct subchannel *sch, __u8 lpm) +{ + char dbf_text[15]; + + if (lpm != 0) + sch->lpm &= ~lpm; + else + sch->lpm = 0; + + CIO_MSG_EVENT(2, "cio_start: 'not oper' status for " + "subchannel 0.%x.%04x!\n", sch->schid.ssid, + sch->schid.sch_no); + + if (cio_update_schib(sch)) + return -ENODEV; + + sprintf(dbf_text, "no%s", dev_name(&sch->dev)); + 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 */ +{ + struct io_subchannel_private *priv = to_io_private(sch); + union orb *orb = &priv->orb; + int ccode; + + CIO_TRACE_EVENT(5, "stIO"); + CIO_TRACE_EVENT(5, dev_name(&sch->dev)); + + memset(orb, 0, sizeof(union orb)); + /* sch is always under 2G. */ + orb->cmd.intparm = (u32)(addr_t)sch; + orb->cmd.fmt = 1; + + orb->cmd.pfch = priv->options.prefetch == 0; + orb->cmd.spnd = priv->options.suspend; + orb->cmd.ssic = priv->options.suspend && priv->options.inter; + orb->cmd.lpm = (lpm != 0) ? lpm : sch->lpm; +#ifdef CONFIG_64BIT + /* + * for 64 bit we always support 64 bit IDAWs with 4k page size only + */ + orb->cmd.c64 = 1; + orb->cmd.i2k = 0; +#endif + orb->cmd.key = key >> 4; + /* issue "Start Subchannel" */ + orb->cmd.cpa = (__u32) __pa(cpa); + ccode = ssch(sch->schid, orb); + + /* process condition code */ + CIO_HEX_EVENT(5, &ccode, sizeof(ccode)); + + switch (ccode) { + case 0: + /* + * initialize device status information + */ + sch->schib.scsw.cmd.actl |= SCSW_ACTL_START_PEND; + return 0; + case 1: /* status pending */ + case 2: /* busy */ + return -EBUSY; + case 3: /* device/path not operational */ + return cio_start_handle_notoper(sch, lpm); + default: + return ccode; + } +} + +int +cio_start (struct subchannel *sch, struct ccw1 *cpa, __u8 lpm) +{ + return cio_start_key(sch, cpa, lpm, PAGE_DEFAULT_KEY); +} + +/* + * resume suspended I/O operation + */ +int +cio_resume (struct subchannel *sch) +{ + int ccode; + + CIO_TRACE_EVENT(4, "resIO"); + CIO_TRACE_EVENT(4, dev_name(&sch->dev)); + + ccode = rsch (sch->schid); + + CIO_HEX_EVENT(4, &ccode, sizeof(ccode)); + + switch (ccode) { + case 0: + sch->schib.scsw.cmd.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) +{ + int ccode; + + if (!sch) + return -ENODEV; + + CIO_TRACE_EVENT(2, "haltIO"); + CIO_TRACE_EVENT(2, dev_name(&sch->dev)); + + /* + * Issue "Halt subchannel" and process condition code + */ + ccode = hsch (sch->schid); + + CIO_HEX_EVENT(2, &ccode, sizeof(ccode)); + + switch (ccode) { + case 0: + sch->schib.scsw.cmd.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) +{ + int ccode; + + if (!sch) + return -ENODEV; + + CIO_TRACE_EVENT(2, "clearIO"); + CIO_TRACE_EVENT(2, dev_name(&sch->dev)); + + /* + * Issue "Clear subchannel" and process condition code + */ + ccode = csch (sch->schid); + + CIO_HEX_EVENT(2, &ccode, sizeof(ccode)); + + switch (ccode) { + case 0: + sch->schib.scsw.cmd.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) +{ + int ccode; + + if (!sch) + return -ENODEV; + + CIO_TRACE_EVENT(2, "cancelIO"); + CIO_TRACE_EVENT(2, dev_name(&sch->dev)); + + ccode = xsch (sch->schid); + + CIO_HEX_EVENT(2, &ccode, sizeof(ccode)); + + switch (ccode) { + case 0: /* success */ + /* Update information in scsw. */ + if (cio_update_schib(sch)) + return -ENODEV; + return 0; + case 1: /* status pending */ + return -EBUSY; + case 2: /* not applicable */ + return -EINVAL; + default: /* not oper */ + return -ENODEV; + } +} + + +static void cio_apply_config(struct subchannel *sch, struct schib *schib) +{ + schib->pmcw.intparm = sch->config.intparm; + schib->pmcw.mbi = sch->config.mbi; + schib->pmcw.isc = sch->config.isc; + schib->pmcw.ena = sch->config.ena; + schib->pmcw.mme = sch->config.mme; + schib->pmcw.mp = sch->config.mp; + schib->pmcw.csense = sch->config.csense; + schib->pmcw.mbfc = sch->config.mbfc; + if (sch->config.mbfc) + schib->mba = sch->config.mba; +} + +static int cio_check_config(struct subchannel *sch, struct schib *schib) +{ + return (schib->pmcw.intparm == sch->config.intparm) && + (schib->pmcw.mbi == sch->config.mbi) && + (schib->pmcw.isc == sch->config.isc) && + (schib->pmcw.ena == sch->config.ena) && + (schib->pmcw.mme == sch->config.mme) && + (schib->pmcw.mp == sch->config.mp) && + (schib->pmcw.csense == sch->config.csense) && + (schib->pmcw.mbfc == sch->config.mbfc) && + (!sch->config.mbfc || (schib->mba == sch->config.mba)); +} + +/* + * cio_commit_config - apply configuration to the subchannel + */ +int cio_commit_config(struct subchannel *sch) +{ + struct schib schib; + int ccode, retry, ret = 0; + + if (stsch_err(sch->schid, &schib) || !css_sch_is_valid(&schib)) + return -ENODEV; + + for (retry = 0; retry < 5; retry++) { + /* copy desired changes to local schib */ + cio_apply_config(sch, &schib); + ccode = msch_err(sch->schid, &schib); + if (ccode < 0) /* -EIO if msch gets a program check. */ + return ccode; + switch (ccode) { + case 0: /* successful */ + if (stsch_err(sch->schid, &schib) || + !css_sch_is_valid(&schib)) + return -ENODEV; + if (cio_check_config(sch, &schib)) { + /* commit changes from local schib */ + memcpy(&sch->schib, &schib, sizeof(schib)); + return 0; + } + ret = -EAGAIN; + break; + 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; +} + +/** + * cio_update_schib - Perform stsch and update schib if subchannel is valid. + * @sch: subchannel on which to perform stsch + * Return zero on success, -ENODEV otherwise. + */ +int cio_update_schib(struct subchannel *sch) +{ + struct schib schib; + + if (stsch_err(sch->schid, &schib) || !css_sch_is_valid(&schib)) + return -ENODEV; + + memcpy(&sch->schib, &schib, sizeof(schib)); + return 0; +} +EXPORT_SYMBOL_GPL(cio_update_schib); + +/** + * cio_enable_subchannel - enable a subchannel. + * @sch: subchannel to be enabled + * @intparm: interruption parameter to set + */ +int cio_enable_subchannel(struct subchannel *sch, u32 intparm) +{ + int retry; + int ret; + + CIO_TRACE_EVENT(2, "ensch"); + CIO_TRACE_EVENT(2, dev_name(&sch->dev)); + + if (sch_is_pseudo_sch(sch)) + return -EINVAL; + if (cio_update_schib(sch)) + return -ENODEV; + + sch->config.ena = 1; + sch->config.isc = sch->isc; + sch->config.intparm = intparm; + + for (retry = 0; retry < 3; retry++) { + ret = cio_commit_config(sch); + if (ret == -EIO) { + /* + * Got a program check in msch. Try without + * the concurrent sense bit the next time. + */ + sch->config.csense = 0; + } else if (ret == -EBUSY) { + struct irb irb; + if (tsch(sch->schid, &irb) != 0) + break; + } else + break; + } + CIO_HEX_EVENT(2, &ret, sizeof(ret)); + return ret; +} +EXPORT_SYMBOL_GPL(cio_enable_subchannel); + +/** + * cio_disable_subchannel - disable a subchannel. + * @sch: subchannel to disable + */ +int cio_disable_subchannel(struct subchannel *sch) +{ + int retry; + int ret; + + CIO_TRACE_EVENT(2, "dissch"); + CIO_TRACE_EVENT(2, dev_name(&sch->dev)); + + if (sch_is_pseudo_sch(sch)) + return 0; + if (cio_update_schib(sch)) + return -ENODEV; + + sch->config.ena = 0; + + for (retry = 0; retry < 3; retry++) { + ret = cio_commit_config(sch); + if (ret == -EBUSY) { + struct irb irb; + if (tsch(sch->schid, &irb) != 0) + break; + } else + break; + } + CIO_HEX_EVENT(2, &ret, sizeof(ret)); + return ret; +} +EXPORT_SYMBOL_GPL(cio_disable_subchannel); + +int cio_create_sch_lock(struct subchannel *sch) +{ + sch->lock = kmalloc(sizeof(spinlock_t), GFP_KERNEL); + if (!sch->lock) + return -ENOMEM; + spin_lock_init(sch->lock); + return 0; +} + +static int cio_check_devno_blacklisted(struct subchannel *sch) +{ + if (is_blacklisted(sch->schid.ssid, 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(6, "Blacklisted device detected " + "at devno %04X, subchannel set %x\n", + sch->schib.pmcw.dev, sch->schid.ssid); + return -ENODEV; + } + return 0; +} + +static int cio_validate_io_subchannel(struct subchannel *sch) +{ + /* Initialization for io subchannels. */ + if (!css_sch_is_valid(&sch->schib)) + return -ENODEV; + + /* Devno is valid. */ + return cio_check_devno_blacklisted(sch); +} + +static int cio_validate_msg_subchannel(struct subchannel *sch) +{ + /* Initialization for message subchannels. */ + if (!css_sch_is_valid(&sch->schib)) + return -ENODEV; + + /* Devno is valid. */ + return cio_check_devno_blacklisted(sch); +} + +/** + * cio_validate_subchannel - basic validation of subchannel + * @sch: subchannel structure to be filled out + * @schid: subchannel id + * + * Find out subchannel type and initialize struct subchannel. + * Return codes: + * 0 on success + * -ENXIO for non-defined subchannels + * -ENODEV for invalid subchannels or blacklisted devices + * -EIO for subchannels in an invalid subchannel set + */ +int cio_validate_subchannel(struct subchannel *sch, struct subchannel_id schid) +{ + char dbf_txt[15]; + int ccode; + int err; + + sprintf(dbf_txt, "valsch%x", schid.sch_no); + CIO_TRACE_EVENT(4, dbf_txt); + + /* Nuke all fields. */ + memset(sch, 0, sizeof(struct subchannel)); + + sch->schid = schid; + if (cio_is_console(schid)) { + sch->lock = cio_get_console_lock(); + } else { + err = cio_create_sch_lock(sch); + if (err) + goto out; + } + mutex_init(&sch->reg_mutex); + + /* + * The first subchannel that is not-operational (ccode==3) + * indicates that there aren't any more devices available. + * If stsch gets an exception, it means the current subchannel set + * is not valid. + */ + ccode = stsch_err (schid, &sch->schib); + if (ccode) { + err = (ccode == 3) ? -ENXIO : ccode; + goto out; + } + /* Copy subchannel type from path management control word. */ + sch->st = sch->schib.pmcw.st; + + switch (sch->st) { + case SUBCHANNEL_TYPE_IO: + err = cio_validate_io_subchannel(sch); + break; + case SUBCHANNEL_TYPE_MSG: + err = cio_validate_msg_subchannel(sch); + break; + default: + err = 0; + } + if (err) + goto out; + + CIO_MSG_EVENT(4, "Subchannel 0.%x.%04x reports subchannel type %04X\n", + sch->schid.ssid, sch->schid.sch_no, sch->st); + return 0; +out: + if (!cio_is_console(schid)) + kfree(sch->lock); + sch->lock = NULL; + return err; +} + +/* + * do_IRQ() handles all normal I/O device IRQ's (the special + * SMP cross-CPU interrupts have their own specific + * handlers). + * + */ +void __irq_entry do_IRQ(struct pt_regs *regs) +{ + struct tpi_info *tpi_info; + struct subchannel *sch; + struct irb *irb; + struct pt_regs *old_regs; + + old_regs = set_irq_regs(regs); + irq_enter(); + __this_cpu_write(s390_idle.nohz_delay, 1); + if (S390_lowcore.int_clock >= S390_lowcore.clock_comparator) + /* Serve timer interrupts first. */ + clock_comparator_work(); + /* + * Get interrupt information from lowcore + */ + tpi_info = (struct tpi_info *)&S390_lowcore.subchannel_id; + irb = (struct irb *)&S390_lowcore.irb; + do { + kstat_cpu(smp_processor_id()).irqs[IO_INTERRUPT]++; + if (tpi_info->adapter_IO) { + do_adapter_IO(tpi_info->isc); + continue; + } + sch = (struct subchannel *)(unsigned long)tpi_info->intparm; + if (!sch) { + /* Clear pending interrupt condition. */ + kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++; + tsch(tpi_info->schid, irb); + continue; + } + spin_lock(sch->lock); + /* Store interrupt response block to lowcore. */ + if (tsch(tpi_info->schid, irb) == 0) { + /* 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); + else + kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++; + } else + kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++; + 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_LPAR && tpi(NULL) != 0); + irq_exit(); + set_irq_regs(old_regs); +} + +#ifdef CONFIG_CCW_CONSOLE +static struct subchannel console_subchannel; +static struct io_subchannel_private console_priv; +static int console_subchannel_in_use; + +/* + * Use cio_tpi to get a pending interrupt and call the interrupt handler. + * Return non-zero if an interrupt was processed, zero otherwise. + */ +static int cio_tpi(void) +{ + struct tpi_info *tpi_info; + struct subchannel *sch; + struct irb *irb; + int irq_context; + + tpi_info = (struct tpi_info *)&S390_lowcore.subchannel_id; + if (tpi(NULL) != 1) + return 0; + kstat_cpu(smp_processor_id()).irqs[IO_INTERRUPT]++; + if (tpi_info->adapter_IO) { + do_adapter_IO(tpi_info->isc); + return 1; + } + irb = (struct irb *)&S390_lowcore.irb; + /* Store interrupt response block to lowcore. */ + if (tsch(tpi_info->schid, irb) != 0) { + /* Not status pending or not operational. */ + kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++; + return 1; + } + sch = (struct subchannel *)(unsigned long)tpi_info->intparm; + if (!sch) { + kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++; + return 1; + } + irq_context = in_interrupt(); + if (!irq_context) + local_bh_disable(); + irq_enter(); + spin_lock(sch->lock); + memcpy(&sch->schib.scsw, &irb->scsw, sizeof(union scsw)); + if (sch->driver && sch->driver->irq) + sch->driver->irq(sch); + else + kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++; + spin_unlock(sch->lock); + irq_exit(); + if (!irq_context) + _local_bh_enable(); + return 1; +} + +void *cio_get_console_priv(void) +{ + return &console_priv; +} + +/* + * busy wait for the next interrupt on the console + */ +void wait_cons_dev(void) + __releases(console_subchannel.lock) + __acquires(console_subchannel.lock) +{ + 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 the console isc */ + __ctl_store (save_cr6, 6, 6); + cr6 = 1UL << (31 - CONSOLE_ISC); + __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.cmd.actl != 0); + /* + * restore previous isc value + */ + __ctl_load (save_cr6, 6, 6); +} + +static int +cio_test_for_console(struct subchannel_id schid, void *data) +{ + if (stsch_err(schid, &console_subchannel.schib) != 0) + return -ENXIO; + if ((console_subchannel.schib.pmcw.st == SUBCHANNEL_TYPE_IO) && + console_subchannel.schib.pmcw.dnv && + (console_subchannel.schib.pmcw.dev == console_devno)) { + console_irq = schid.sch_no; + return 1; /* found */ + } + return 0; +} + + +static int +cio_get_console_sch_no(void) +{ + struct subchannel_id schid; + + init_subchannel_id(&schid); + if (console_irq != -1) { + /* VM provided us with the irq number of the console. */ + schid.sch_no = console_irq; + if (stsch_err(schid, &console_subchannel.schib) != 0 || + (console_subchannel.schib.pmcw.st != SUBCHANNEL_TYPE_IO) || + !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_each_subchannel(cio_test_for_console, NULL); + 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 */ + return -1; + } + return console_irq; +} + +struct subchannel * +cio_probe_console(void) +{ + int sch_no, ret; + struct subchannel_id schid; + + if (xchg(&console_subchannel_in_use, 1) != 0) + return ERR_PTR(-EBUSY); + sch_no = cio_get_console_sch_no(); + if (sch_no == -1) { + console_subchannel_in_use = 0; + pr_warning("No CCW console was found\n"); + return ERR_PTR(-ENODEV); + } + memset(&console_subchannel, 0, sizeof(struct subchannel)); + init_subchannel_id(&schid); + schid.sch_no = sch_no; + ret = cio_validate_subchannel(&console_subchannel, schid); + if (ret) { + console_subchannel_in_use = 0; + return ERR_PTR(-ENODEV); + } + + /* + * enable console I/O-interrupt subclass + */ + isc_register(CONSOLE_ISC); + console_subchannel.config.isc = CONSOLE_ISC; + console_subchannel.config.intparm = (u32)(addr_t)&console_subchannel; + ret = cio_commit_config(&console_subchannel); + if (ret) { + isc_unregister(CONSOLE_ISC); + console_subchannel_in_use = 0; + return ERR_PTR(ret); + } + return &console_subchannel; +} + +void +cio_release_console(void) +{ + console_subchannel.config.intparm = 0; + cio_commit_config(&console_subchannel); + isc_unregister(CONSOLE_ISC); + console_subchannel_in_use = 0; +} + +/* Bah... hack to catch console special sausages. */ +int +cio_is_console(struct subchannel_id schid) +{ + if (!console_subchannel_in_use) + return 0; + return schid_equal(&schid, &console_subchannel.schid); +} + +struct subchannel * +cio_get_console_subchannel(void) +{ + if (!console_subchannel_in_use) + return NULL; + return &console_subchannel; +} + +#endif +static int +__disable_subchannel_easy(struct subchannel_id schid, struct schib *schib) +{ + int retry, cc; + + cc = 0; + for (retry=0;retry<3;retry++) { + schib->pmcw.ena = 0; + cc = msch_err(schid, schib); + if (cc) + return (cc==3?-ENODEV:-EBUSY); + if (stsch_err(schid, schib) || !css_sch_is_valid(schib)) + return -ENODEV; + if (!schib->pmcw.ena) + return 0; + } + return -EBUSY; /* uhm... */ +} + +static int +__clear_io_subchannel_easy(struct subchannel_id schid) +{ + int retry; + + if (csch(schid)) + return -ENODEV; + for (retry=0;retry<20;retry++) { + struct tpi_info ti; + + if (tpi(&ti)) { + tsch(ti.schid, (struct irb *)&S390_lowcore.irb); + if (schid_equal(&ti.schid, &schid)) + return 0; + } + udelay_simple(100); + } + return -EBUSY; +} + +static void __clear_chsc_subchannel_easy(void) +{ + /* It seems we can only wait for a bit here :/ */ + udelay_simple(100); +} + +static int pgm_check_occured; + +static void cio_reset_pgm_check_handler(void) +{ + pgm_check_occured = 1; +} + +static int stsch_reset(struct subchannel_id schid, struct schib *addr) +{ + int rc; + + pgm_check_occured = 0; + s390_base_pgm_handler_fn = cio_reset_pgm_check_handler; + rc = stsch_err(schid, addr); + s390_base_pgm_handler_fn = NULL; + + /* The program check handler could have changed pgm_check_occured. */ + barrier(); + + if (pgm_check_occured) + return -EIO; + else + return rc; +} + +static int __shutdown_subchannel_easy(struct subchannel_id schid, void *data) +{ + struct schib schib; + + if (stsch_reset(schid, &schib)) + return -ENXIO; + if (!schib.pmcw.ena) + return 0; + switch(__disable_subchannel_easy(schid, &schib)) { + case 0: + case -ENODEV: + break; + default: /* -EBUSY */ + switch (schib.pmcw.st) { + case SUBCHANNEL_TYPE_IO: + if (__clear_io_subchannel_easy(schid)) + goto out; /* give up... */ + break; + case SUBCHANNEL_TYPE_CHSC: + __clear_chsc_subchannel_easy(); + break; + default: + /* No default clear strategy */ + break; + } + stsch_err(schid, &schib); + __disable_subchannel_easy(schid, &schib); + } +out: + return 0; +} + +static atomic_t chpid_reset_count; + +static void s390_reset_chpids_mcck_handler(void) +{ + struct crw crw; + struct mci *mci; + + /* Check for pending channel report word. */ + mci = (struct mci *)&S390_lowcore.mcck_interruption_code; + if (!mci->cp) + return; + /* Process channel report words. */ + while (stcrw(&crw) == 0) { + /* Check for responses to RCHP. */ + if (crw.slct && crw.rsc == CRW_RSC_CPATH) + atomic_dec(&chpid_reset_count); + } +} + +#define RCHP_TIMEOUT (30 * USEC_PER_SEC) +static void css_reset(void) +{ + int i, ret; + unsigned long long timeout; + struct chp_id chpid; + + /* Reset subchannels. */ + for_each_subchannel(__shutdown_subchannel_easy, NULL); + /* Reset channel paths. */ + s390_base_mcck_handler_fn = s390_reset_chpids_mcck_handler; + /* Enable channel report machine checks. */ + __ctl_set_bit(14, 28); + /* Temporarily reenable machine checks. */ + local_mcck_enable(); + chp_id_init(&chpid); + for (i = 0; i <= __MAX_CHPID; i++) { + chpid.id = i; + ret = rchp(chpid); + if ((ret == 0) || (ret == 2)) + /* + * rchp either succeeded, or another rchp is already + * in progress. In either case, we'll get a crw. + */ + atomic_inc(&chpid_reset_count); + } + /* Wait for machine check for all channel paths. */ + timeout = get_clock() + (RCHP_TIMEOUT << 12); + while (atomic_read(&chpid_reset_count) != 0) { + if (get_clock() > timeout) + break; + cpu_relax(); + } + /* Disable machine checks again. */ + local_mcck_disable(); + /* Disable channel report machine checks. */ + __ctl_clear_bit(14, 28); + s390_base_mcck_handler_fn = NULL; +} + +static struct reset_call css_reset_call = { + .fn = css_reset, +}; + +static int __init init_css_reset_call(void) +{ + atomic_set(&chpid_reset_count, 0); + register_reset_call(&css_reset_call); + return 0; +} + +arch_initcall(init_css_reset_call); + +struct sch_match_id { + struct subchannel_id schid; + struct ccw_dev_id devid; + int rc; +}; + +static int __reipl_subchannel_match(struct subchannel_id schid, void *data) +{ + struct schib schib; + struct sch_match_id *match_id = data; + + if (stsch_reset(schid, &schib)) + return -ENXIO; + if ((schib.pmcw.st == SUBCHANNEL_TYPE_IO) && schib.pmcw.dnv && + (schib.pmcw.dev == match_id->devid.devno) && + (schid.ssid == match_id->devid.ssid)) { + match_id->schid = schid; + match_id->rc = 0; + return 1; + } + return 0; +} + +static int reipl_find_schid(struct ccw_dev_id *devid, + struct subchannel_id *schid) +{ + struct sch_match_id match_id; + + match_id.devid = *devid; + match_id.rc = -ENODEV; + for_each_subchannel(__reipl_subchannel_match, &match_id); + if (match_id.rc == 0) + *schid = match_id.schid; + return match_id.rc; +} + +extern void do_reipl_asm(__u32 schid); + +/* Make sure all subchannels are quiet before we re-ipl an lpar. */ +void reipl_ccw_dev(struct ccw_dev_id *devid) +{ + struct subchannel_id schid; + + s390_reset_system(NULL, NULL); + if (reipl_find_schid(devid, &schid) != 0) + panic("IPL Device not found\n"); + do_reipl_asm(*((__u32*)&schid)); +} + +int __init cio_get_iplinfo(struct cio_iplinfo *iplinfo) +{ + struct subchannel_id schid; + struct schib schib; + + schid = *(struct subchannel_id *)&S390_lowcore.subchannel_id; + if (!schid.one) + return -ENODEV; + if (stsch_err(schid, &schib)) + return -ENODEV; + if (schib.pmcw.st != SUBCHANNEL_TYPE_IO) + return -ENODEV; + if (!schib.pmcw.dnv) + return -ENODEV; + iplinfo->devno = schib.pmcw.dev; + iplinfo->is_qdio = schib.pmcw.qf; + return 0; +} + +/** + * cio_tm_start_key - perform start function + * @sch: subchannel on which to perform the start function + * @tcw: transport-command word to be started + * @lpm: mask of paths to use + * @key: storage key to use for storage access + * + * Start the tcw on the given subchannel. Return zero on success, non-zero + * otherwise. + */ +int cio_tm_start_key(struct subchannel *sch, struct tcw *tcw, u8 lpm, u8 key) +{ + int cc; + union orb *orb = &to_io_private(sch)->orb; + + memset(orb, 0, sizeof(union orb)); + orb->tm.intparm = (u32) (addr_t) sch; + orb->tm.key = key >> 4; + orb->tm.b = 1; + orb->tm.lpm = lpm ? lpm : sch->lpm; + orb->tm.tcw = (u32) (addr_t) tcw; + cc = ssch(sch->schid, orb); + switch (cc) { + case 0: + return 0; + case 1: + case 2: + return -EBUSY; + default: + return cio_start_handle_notoper(sch, lpm); + } +} + +/** + * cio_tm_intrg - perform interrogate function + * @sch - subchannel on which to perform the interrogate function + * + * If the specified subchannel is running in transport-mode, perform the + * interrogate function. Return zero on success, non-zero otherwie. + */ +int cio_tm_intrg(struct subchannel *sch) +{ + int cc; + + if (!to_io_private(sch)->orb.tm.b) + return -EINVAL; + cc = xsch(sch->schid); + switch (cc) { + case 0: + case 2: + return 0; + case 1: + return -EBUSY; + default: + return -ENODEV; + } +} |