+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;
+
+ /* Reset subchannels. */
+ for_each_subchannel(__shutdown_subchannel_easy, NULL);
+ /* Reset channel paths. */
+ s390_reset_mcck_handler = s390_reset_chpids_mcck_handler;
+ /* Enable channel report machine checks. */
+ __ctl_set_bit(14, 28);
+ /* Temporarily reenable machine checks. */
+ local_mcck_enable();
+ for (i = 0; i <= __MAX_CHPID; i++) {
+ ret = rchp(i);
+ 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_reset_mcck_handler = 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.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)