Set up some hardware registers and creates interrupt service routines
for the doorbells and messages.
There are 64 doorbells in the switch that are shared between all
partitions. The upper 4 doorbells are also shared with the messages
and are there for not used. Thus, this provides 28 doorbells for each
partition.
Signed-off-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>
Reviewed-by: Stephen Bates <sbates@xxxxxxxxxxxx>
Reviewed-by: Kurt Schwemmer <kurt.schwemmer@xxxxxxxxxxxxx>
---
drivers/ntb/hw/mscc/switchtec_ntb.c | 142 ++++++++++++++++++++++++++++++++++++
1 file changed, 142 insertions(+)
diff --git a/drivers/ntb/hw/mscc/switchtec_ntb.c b/drivers/ntb/hw/mscc/switchtec_ntb.c
index 1596757413f5..877337902363 100644
--- a/drivers/ntb/hw/mscc/switchtec_ntb.c
+++ b/drivers/ntb/hw/mscc/switchtec_ntb.c
@@ -17,6 +17,7 @@
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/kthread.h>
+#include <linux/interrupt.h>
MODULE_DESCRIPTION("Microsemi Switchtec(tm) NTB Driver");
MODULE_VERSION("0.1");
@@ -75,6 +76,9 @@ struct switchtec_ntb {
int self_partition;
int peer_partition;
+ int doorbell_irq;
+ int message_irq;
+
struct ntb_info_regs __iomem *mmio_ntb;
struct ntb_ctrl_regs __iomem *mmio_ctrl;
struct ntb_dbmsg_regs __iomem *mmio_dbmsg;
@@ -86,6 +90,11 @@ struct switchtec_ntb {
struct shared_mw __iomem *peer_shared;
dma_addr_t self_shared_dma;
+ u64 db_mask;
+ u64 db_valid_mask;
+ int db_shift;
+ int db_peer_shift;
+
int nr_direct_mw;
int nr_lut_mw;
int direct_mw_to_bar[MAX_DIRECT_MW];
@@ -215,6 +224,49 @@ static void switchtec_ntb_init_mw(struct switchtec_ntb *sndev)
}
+/*
+ * There are 64 doorbells in the switch hardware but this is
+ * shared among all partitions. So we must split them in half
+ * (32 for each partition). However, the message interrupts are
+ * also shared with the top 4 doorbells so we just limit this to
+ * 28 doorbells per partition
+ */
+static void switchtec_ntb_init_db(struct switchtec_ntb *sndev)
+{
+ sndev->db_valid_mask = 0x0FFFFFFF;
+
+ if (sndev->self_partition < sndev->peer_partition) {
+ sndev->db_shift = 0;
+ sndev->db_peer_shift = 32;
+ } else {
+ sndev->db_shift = 32;
+ sndev->db_peer_shift = 0;
+ }
+
+ sndev->db_mask = 0x0FFFFFFFFFFFFFFFULL;
+ iowrite64(~sndev->db_mask, &sndev->mmio_self_dbmsg->idb_mask);
+ iowrite64(sndev->db_valid_mask << sndev->db_peer_shift,
+ &sndev->mmio_self_dbmsg->odb_mask);
+}
+
+static void switchtec_ntb_init_msgs(struct switchtec_ntb *sndev)
+{
+ int i;
+ u32 msg_map = 0;
+
+ for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++) {
+ int m = i | sndev->peer_partition << 2;
+
+ msg_map |= m << i * 8;
+ }
+
+ iowrite32(msg_map, &sndev->mmio_self_dbmsg->msg_map);
+
+ for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++)
+ iowrite64(NTB_DBMSG_IMSG_STATUS | NTB_DBMSG_IMSG_MASK,
+ &sndev->mmio_self_dbmsg->imsg[i]);
+}
+
static int switchtec_ntb_init_req_id_table(struct switchtec_ntb *sndev)
{
int rc = 0;
@@ -359,6 +411,87 @@ static void switchtec_ntb_deinit_shared_mw(struct switchtec_ntb *sndev)
sndev->self_shared_dma);
}
+static irqreturn_t switchtec_ntb_doorbell_isr(int irq, void *dev)
+{
+ struct switchtec_ntb *sndev = dev;
+
+ dev_dbg(&sndev->stdev->dev, "doorbell\n");
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t switchtec_ntb_message_isr(int irq, void *dev)
+{
+ int i;
+ struct switchtec_ntb *sndev = dev;
+
+ for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++) {
+ u64 msg = ioread64(&sndev->mmio_self_dbmsg->imsg[i]);
+
+ if (msg & NTB_DBMSG_IMSG_STATUS) {
+ dev_dbg(&sndev->stdev->dev, "message: %d %08x\n", i,
+ (u32)msg);
+ iowrite8(1, &sndev->mmio_self_dbmsg->imsg[i].status);
+ }
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int switchtec_ntb_init_db_msg_irq(struct switchtec_ntb *sndev)
+{
+ int i;
+ int rc;
+ int doorbell_irq = 0;
+ int message_irq = 0;
+ int event_irq;
+ int idb_vecs = sizeof(sndev->mmio_self_dbmsg->idb_vec_map);
+
+ event_irq = ioread32(&sndev->stdev->mmio_part_cfg->vep_vector_number);
+
+ while (doorbell_irq == event_irq)
+ doorbell_irq++;
+ while (message_irq == doorbell_irq ||
+ message_irq == event_irq)
+ message_irq++;
+
+ dev_dbg(&sndev->stdev->dev, "irqs - event: %d, db: %d, msgs: %d",
+ event_irq, doorbell_irq, message_irq);
+
+ for (i = 0; i < idb_vecs - 4; i++)
+ iowrite8(doorbell_irq,
+ &sndev->mmio_self_dbmsg->idb_vec_map[i]);
+
+ for (; i < idb_vecs; i++)
+ iowrite8(message_irq,
+ &sndev->mmio_self_dbmsg->idb_vec_map[i]);
+
+ sndev->doorbell_irq = pci_irq_vector(sndev->stdev->pdev, doorbell_irq);
+ sndev->message_irq = pci_irq_vector(sndev->stdev->pdev, message_irq);
+
+ rc = request_irq(sndev->doorbell_irq,
+ switchtec_ntb_doorbell_isr, 0,
+ "switchtec_ntb_doorbell", sndev);
+ if (rc)
+ return rc;
+
+ rc = request_irq(sndev->message_irq,
+ switchtec_ntb_message_isr, 0,
+ "switchtec_ntb_message", sndev);
+ if (rc) {
+ free_irq(sndev->doorbell_irq, sndev);
+ return rc;
+ }
+
+ return 0;
+}
+
+static void switchtec_ntb_deinit_db_msg_irq(struct switchtec_ntb *sndev)
+{
+ free_irq(sndev->doorbell_irq, sndev);
+ free_irq(sndev->message_irq, sndev);
+}
+
static int switchtec_ntb_add(struct device *dev,
struct class_interface *class_intf)
{
@@ -382,6 +515,8 @@ static int switchtec_ntb_add(struct device *dev,
switchtec_ntb_init_sndev(sndev);
switchtec_ntb_init_mw(sndev);
+ switchtec_ntb_init_db(sndev);
+ switchtec_ntb_init_msgs(sndev);
rc = switchtec_ntb_init_req_id_table(sndev);
if (rc)
@@ -391,11 +526,17 @@ static int switchtec_ntb_add(struct device *dev,
if (rc)
goto free_and_exit;
+ rc = switchtec_ntb_init_db_msg_irq(sndev);
+ if (rc)
+ goto deinit_shared_and_exit;
+
stdev->sndev = sndev;
dev_info(dev, "NTB device registered");
return 0;
+deinit_shared_and_exit:
+ switchtec_ntb_deinit_shared_mw(sndev);
free_and_exit:
kfree(sndev);
dev_err(dev, "failed to register ntb device: %d", rc);
@@ -412,6 +553,7 @@ void switchtec_ntb_remove(struct device *dev,
return;
stdev->sndev = NULL;
+ switchtec_ntb_deinit_db_msg_irq(sndev);
switchtec_ntb_deinit_shared_mw(sndev);
kfree(sndev);
dev_info(dev, "ntb device unregistered");
--
2.11.0
