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-rw-r--r--drivers/s390/cio/cio.c860
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 000000000000..99ce5a567982
--- /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);
+}
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-06-04 01:23:38 +0200