1 files changed, 100 insertions, 28 deletions

diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
index 8936e460a807..20aee2783847 100644
--- a/drivers/s390/cio/cio.c
+++ b/drivers/s390/cio/cio.c
@@ -21,6 +21,7 @@
 #include <asm/irq.h>
 #include <asm/irq_regs.h>
 #include <asm/setup.h>
+#include <asm/reset.h>
 #include "airq.h"
 #include "cio.h"
 #include "css.h"
@@ -28,6 +29,7 @@
 #include "ioasm.h"
 #include "blacklist.h"
 #include "cio_debug.h"
+#include "../s390mach.h"
 
 debug_info_t *cio_debug_msg_id;
 debug_info_t *cio_debug_trace_id;
@@ -841,26 +843,12 @@ __clear_subchannel_easy(struct subchannel_id schid)
         return -EBUSY;
 }
 
-struct sch_match_id {
-        struct subchannel_id schid;
-        struct ccw_dev_id devid;
-        int rc;
-};
-
-static int __shutdown_subchannel_easy_and_match(struct subchannel_id schid,
-        void *data)
+static int __shutdown_subchannel_easy(struct subchannel_id schid, void *data)
 {
         struct schib schib;
-        struct sch_match_id *match_id = data;
 
         if (stsch_err(schid, &schib))
                 return -ENXIO;
-        if (match_id && schib.pmcw.dnv &&
-                (schib.pmcw.dev == match_id->devid.devno) &&
-                (schid.ssid == match_id->devid.ssid)) {
-                match_id->schid = schid;
-                match_id->rc = 0;
-        }
         if (!schib.pmcw.ena)
                 return 0;
         switch(__disable_subchannel_easy(schid, &schib)) {
@@ -876,27 +864,111 @@ static int __shutdown_subchannel_easy_and_match(struct subchannel_id schid,
         return 0;
 }
 
-static int clear_all_subchannels_and_match(struct ccw_dev_id *devid,
-        struct subchannel_id *schid)
+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_err(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)
 {
         struct sch_match_id match_id;
 
         match_id.devid = *devid;
         match_id.rc = -ENODEV;
-        local_irq_disable();
-        for_each_subchannel(__shutdown_subchannel_easy_and_match, &match_id);
+        for_each_subchannel(__reipl_subchannel_match, &match_id);
         if (match_id.rc == 0)
                 *schid = match_id.schid;
         return match_id.rc;
 }
 
-
-void clear_all_subchannels(void)
-{
-        local_irq_disable();
-        for_each_subchannel(__shutdown_subchannel_easy_and_match, NULL);
-}
-
 extern void do_reipl_asm(__u32 schid);
 
 /* Make sure all subchannels are quiet before we re-ipl an lpar. */
@@ -904,9 +976,9 @@ void reipl_ccw_dev(struct ccw_dev_id *devid)
 {
         struct subchannel_id schid;
 
-        if (clear_all_subchannels_and_match(devid, &schid))
+        s390_reset_system();
+        if (reipl_find_schid(devid, &schid) != 0)
                 panic("IPL Device not found\n");
-        cio_reset_channel_paths();
         do_reipl_asm(*((__u32*)&schid));
 }