These changes are the raw update to linux-4.4.6-rt14. Kernel sources
[kvmfornfv.git] / kernel / drivers / scsi / snic / snic_isr.c
diff --git a/kernel/drivers/scsi/snic/snic_isr.c b/kernel/drivers/scsi/snic/snic_isr.c
new file mode 100644 (file)
index 0000000..a85fae2
--- /dev/null
@@ -0,0 +1,204 @@
+/*
+ * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+
+#include "vnic_dev.h"
+#include "vnic_intr.h"
+#include "vnic_stats.h"
+#include "snic_io.h"
+#include "snic.h"
+
+
+/*
+ * snic_isr_msix_wq : MSIx ISR for work queue.
+ */
+
+static irqreturn_t
+snic_isr_msix_wq(int irq, void *data)
+{
+       struct snic *snic = data;
+       unsigned long wq_work_done = 0;
+
+       snic->s_stats.misc.last_isr_time = jiffies;
+       atomic64_inc(&snic->s_stats.misc.isr_cnt);
+
+       wq_work_done = snic_wq_cmpl_handler(snic, -1);
+       svnic_intr_return_credits(&snic->intr[SNIC_MSIX_WQ],
+                                 wq_work_done,
+                                 1 /* unmask intr */,
+                                 1 /* reset intr timer */);
+
+       return IRQ_HANDLED;
+} /* end of snic_isr_msix_wq */
+
+static irqreturn_t
+snic_isr_msix_io_cmpl(int irq, void *data)
+{
+       struct snic *snic = data;
+       unsigned long iocmpl_work_done = 0;
+
+       snic->s_stats.misc.last_isr_time = jiffies;
+       atomic64_inc(&snic->s_stats.misc.isr_cnt);
+
+       iocmpl_work_done = snic_fwcq_cmpl_handler(snic, -1);
+       svnic_intr_return_credits(&snic->intr[SNIC_MSIX_IO_CMPL],
+                                 iocmpl_work_done,
+                                 1 /* unmask intr */,
+                                 1 /* reset intr timer */);
+
+       return IRQ_HANDLED;
+} /* end of snic_isr_msix_io_cmpl */
+
+static irqreturn_t
+snic_isr_msix_err_notify(int irq, void *data)
+{
+       struct snic *snic = data;
+
+       snic->s_stats.misc.last_isr_time = jiffies;
+       atomic64_inc(&snic->s_stats.misc.isr_cnt);
+
+       svnic_intr_return_all_credits(&snic->intr[SNIC_MSIX_ERR_NOTIFY]);
+       snic_log_q_error(snic);
+
+       /*Handling link events */
+       snic_handle_link_event(snic);
+
+       return IRQ_HANDLED;
+} /* end of snic_isr_msix_err_notify */
+
+
+void
+snic_free_intr(struct snic *snic)
+{
+       int i;
+
+       /* ONLY interrupt mode MSIX is supported */
+       for (i = 0; i < ARRAY_SIZE(snic->msix); i++) {
+               if (snic->msix[i].requested) {
+                       free_irq(snic->msix_entry[i].vector,
+                                snic->msix[i].devid);
+               }
+       }
+} /* end of snic_free_intr */
+
+int
+snic_request_intr(struct snic *snic)
+{
+       int ret = 0, i;
+       enum vnic_dev_intr_mode intr_mode;
+
+       intr_mode = svnic_dev_get_intr_mode(snic->vdev);
+       SNIC_BUG_ON(intr_mode != VNIC_DEV_INTR_MODE_MSIX);
+
+       /*
+        * Currently HW supports single WQ and CQ. So passing devid as snic.
+        * When hardware supports multiple WQs and CQs, one idea is
+        * to pass devid as corresponding WQ or CQ ptr and retrieve snic
+        * from queue ptr.
+        * Except for err_notify, which is always one.
+        */
+       sprintf(snic->msix[SNIC_MSIX_WQ].devname,
+               "%.11s-scsi-wq",
+               snic->name);
+       snic->msix[SNIC_MSIX_WQ].isr = snic_isr_msix_wq;
+       snic->msix[SNIC_MSIX_WQ].devid = snic;
+
+       sprintf(snic->msix[SNIC_MSIX_IO_CMPL].devname,
+               "%.11s-io-cmpl",
+               snic->name);
+       snic->msix[SNIC_MSIX_IO_CMPL].isr = snic_isr_msix_io_cmpl;
+       snic->msix[SNIC_MSIX_IO_CMPL].devid = snic;
+
+       sprintf(snic->msix[SNIC_MSIX_ERR_NOTIFY].devname,
+               "%.11s-err-notify",
+               snic->name);
+       snic->msix[SNIC_MSIX_ERR_NOTIFY].isr = snic_isr_msix_err_notify;
+       snic->msix[SNIC_MSIX_ERR_NOTIFY].devid = snic;
+
+       for (i = 0; i < ARRAY_SIZE(snic->msix); i++) {
+               ret = request_irq(snic->msix_entry[i].vector,
+                                 snic->msix[i].isr,
+                                 0,
+                                 snic->msix[i].devname,
+                                 snic->msix[i].devid);
+               if (ret) {
+                       SNIC_HOST_ERR(snic->shost,
+                                     "MSI-X: requrest_irq(%d) failed %d\n",
+                                     i,
+                                     ret);
+                       snic_free_intr(snic);
+                       break;
+               }
+               snic->msix[i].requested = 1;
+       }
+
+       return ret;
+} /* end of snic_requrest_intr */
+
+int
+snic_set_intr_mode(struct snic *snic)
+{
+       unsigned int n = ARRAY_SIZE(snic->wq);
+       unsigned int m = SNIC_CQ_IO_CMPL_MAX;
+       unsigned int i;
+
+       /*
+        * We need n WQs, m CQs, and n+m+1 INTRs
+        * (last INTR is used for WQ/CQ errors and notification area
+        */
+
+       BUILD_BUG_ON((ARRAY_SIZE(snic->wq) + SNIC_CQ_IO_CMPL_MAX) >
+                       ARRAY_SIZE(snic->intr));
+       SNIC_BUG_ON(ARRAY_SIZE(snic->msix_entry) < (n + m + 1));
+
+       for (i = 0; i < (n + m + 1); i++)
+               snic->msix_entry[i].entry = i;
+
+       if (snic->wq_count >= n && snic->cq_count >= (n + m)) {
+               if (!pci_enable_msix(snic->pdev,
+                                    snic->msix_entry,
+                                    (n + m + 1))) {
+                       snic->wq_count = n;
+                       snic->cq_count = n + m;
+                       snic->intr_count = n + m + 1;
+                       snic->err_intr_offset = SNIC_MSIX_ERR_NOTIFY;
+
+                       SNIC_ISR_DBG(snic->shost,
+                                    "Using MSI-X Interrupts\n");
+                       svnic_dev_set_intr_mode(snic->vdev,
+                                               VNIC_DEV_INTR_MODE_MSIX);
+
+                       return 0;
+               }
+       }
+
+       svnic_dev_set_intr_mode(snic->vdev, VNIC_DEV_INTR_MODE_UNKNOWN);
+
+       return -EINVAL;
+} /* end of snic_set_intr_mode */
+
+void
+snic_clear_intr_mode(struct snic *snic)
+{
+       pci_disable_msix(snic->pdev);
+
+       svnic_dev_set_intr_mode(snic->vdev, VNIC_DEV_INTR_MODE_INTX);
+}