ioat: Add sysctl to force hw reset

To enable controlled testing.

Sponsored by:	EMC / Isilon Storage Division

diff --git a/sys/dev/ioat/ioat.c b/sys/dev/ioat/ioat.c
index 89fafb37a0b031161ae8a47e53c589a7930e751c..730d2b3faad9e6fe90c34b68236ec6a16bba38b0 100644 (file)
--- a/sys/dev/ioat/ioat.c
+++ b/sys/dev/ioat/ioat.c
@@ -82,6 +82,7 @@ static void ioat_comp_update_map(void *arg, bus_dma_segment_t *seg, int nseg,
     int error);
 static int ioat_reset_hw(struct ioat_softc *ioat);
 static void ioat_setup_sysctl(device_t device);
+static int sysctl_handle_reset(SYSCTL_HANDLER_ARGS);
 static inline struct ioat_softc *ioat_get(struct ioat_softc *,
     enum ioat_ref_kind);
 static inline void ioat_put(struct ioat_softc *, enum ioat_ref_kind);
@@ -1028,8 +1029,10 @@ ioat_reset_hw(struct ioat_softc *ioat)
         * BDXDE and BWD models reset MSI-X registers on device reset.
         * Save/restore their contents manually.
         */
-       if (ioat_model_resets_msix(ioat))
+       if (ioat_model_resets_msix(ioat)) {
+               ioat_log_message(1, "device resets MSI-X registers; saving\n");
                pci_save_state(ioat->device);
+       }
 
        ioat_reset(ioat);
 
@@ -1039,12 +1042,37 @@ ioat_reset_hw(struct ioat_softc *ioat)
        if (timeout == 20)
                return (ETIMEDOUT);
 
-       if (ioat_model_resets_msix(ioat))
+       if (ioat_model_resets_msix(ioat)) {
+               ioat_log_message(1, "device resets registers; restored\n");
                pci_restore_state(ioat->device);
+       }
 
        return (0);
 }
 
+static int
+sysctl_handle_reset(SYSCTL_HANDLER_ARGS)
+{
+       struct ioat_softc *ioat;
+       int error, arg;
+
+       ioat = arg1;
+
+       arg = 0;
+       error = SYSCTL_OUT(req, &arg, sizeof(arg));
+       if (error != 0 || req->newptr == NULL)
+               return (error);
+
+       error = SYSCTL_IN(req, &arg, sizeof(arg));
+       if (error != 0)
+               return (error);
+
+       if (arg != 0)
+               error = ioat_reset_hw(ioat);
+
+       return (error);
+}
+
 static void
 dump_descriptor(void *hw_desc)
 {
@@ -1060,23 +1088,26 @@ dump_descriptor(void *hw_desc)
 static void
 ioat_setup_sysctl(device_t device)
 {
-       struct sysctl_ctx_list *sysctl_ctx;
-       struct sysctl_oid *sysctl_tree;
+       struct sysctl_oid_list *par;
+       struct sysctl_ctx_list *ctx;
+       struct sysctl_oid *tree;
        struct ioat_softc *ioat;
 
        ioat = DEVICE2SOFTC(device);
-       sysctl_ctx = device_get_sysctl_ctx(device);
-       sysctl_tree = device_get_sysctl_tree(device);
-
-       SYSCTL_ADD_UINT(sysctl_ctx, SYSCTL_CHILDREN(sysctl_tree), OID_AUTO,
-           "ring_size_order", CTLFLAG_RD, &ioat->ring_size_order,
-           0, "HW descriptor ring size order");
-       SYSCTL_ADD_UINT(sysctl_ctx, SYSCTL_CHILDREN(sysctl_tree), OID_AUTO,
-           "head", CTLFLAG_RD, &ioat->head,
-           0, "HW descriptor head pointer index");
-       SYSCTL_ADD_UINT(sysctl_ctx, SYSCTL_CHILDREN(sysctl_tree), OID_AUTO,
-           "tail", CTLFLAG_RD, &ioat->tail,
-           0, "HW descriptor tail pointer index");
+       ctx = device_get_sysctl_ctx(device);
+       tree = device_get_sysctl_tree(device);
+       par = SYSCTL_CHILDREN(tree);
+
+       SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "ring_size_order", CTLFLAG_RD,
+           &ioat->ring_size_order, 0, "HW descriptor ring size order");
+       SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "head", CTLFLAG_RD, &ioat->head, 0,
+           "HW descriptor head pointer index");
+       SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "tail", CTLFLAG_RD, &ioat->tail, 0,
+           "HW descriptor tail pointer index");
+
+       SYSCTL_ADD_PROC(ctx, par, OID_AUTO, "force_hw_reset",
+           CTLTYPE_INT | CTLFLAG_RW, ioat, 0, sysctl_handle_reset, "I",
+           "Set to non-zero to reset the hardware");
 }
 
 static inline struct ioat_softc *