From: Kelvin Cao <kelvin....@microsemi.com>
Allow using Switchtec NTB in setups that have more than two partitions.
Note: this does not enable having multi-host communication, it only
allows for a single NTB link between two hosts in a network that might
have more than two.
Use following logic to determine the NT peer partition:
1) If there are 2 partitions, and the target vector is set in
the Switchtec configuration, use the partition specified in target
vector.
2) If there are 2 partitions and target vector is unset
use the only other partition as specified in the NT EP map.
3) If there are more than 2 partitions and target vector is set
use the other partition specified in target vector.
4) If there are more than 2 partitions and target vector is unset,
this is invalid and report an error.
Signed-off-by: Kelvin Cao <kelvin....@microsemi.com>
[log...@deltatee.com: commit message fleshed out]
Signed-off-by: Logan Gunthorpe <log...@deltatee.com>
Reviewed-by: Logan Gunthorpe <log...@deltatee.com>
---
drivers/ntb/hw/mscc/ntb_hw_switchtec.c | 57 ++++++++++++++++++++++++++++------
include/linux/switchtec.h | 8 +++++
2 files changed, 56 insertions(+), 9 deletions(-)
diff --git a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c
b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c
index 709f37fbe232..088ae220ecb4 100644
--- a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c
+++ b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c
@@ -777,9 +777,12 @@ static const struct ntb_dev_ops switchtec_ntb_ops = {
.peer_spad_addr = switchtec_ntb_peer_spad_addr,
};
-static void switchtec_ntb_init_sndev(struct switchtec_ntb *sndev)
+static int switchtec_ntb_init_sndev(struct switchtec_ntb *sndev)
{
+ u64 tpart_vec;
+ int self;
u64 part_map;
+ int bit;
sndev->ntb.pdev = sndev->stdev->pdev;
sndev->ntb.topo = NTB_TOPO_SWITCH;
@@ -788,13 +791,47 @@ static void switchtec_ntb_init_sndev(struct switchtec_ntb
*sndev)
sndev->self_partition = sndev->stdev->partition;
sndev->mmio_ntb = sndev->stdev->mmio_ntb;
+
+ self = sndev->self_partition;
+ tpart_vec = ioread32(&sndev->mmio_ntb->ntp_info[self].target_part_high);
+ tpart_vec <<= 32;
+ tpart_vec |= ioread32(&sndev->mmio_ntb->ntp_info[self].target_part_low);
+
part_map = ioread64(&sndev->mmio_ntb->ep_map);
part_map &= ~(1 << sndev->self_partition);
- sndev->peer_partition = ffs(part_map) - 1;
- dev_dbg(&sndev->stdev->dev, "Partition ID %d of %d (%llx)\n",
- sndev->self_partition, sndev->stdev->partition_count,
- part_map);
+ if (!ffs(tpart_vec)) {
+ if (sndev->stdev->partition_count != 2) {
+ dev_err(&sndev->stdev->dev,
+ "ntb target partition not defined\n");
+ return -ENODEV;
+ }
+
+ bit = ffs(part_map);
+ if (!bit) {
+ dev_err(&sndev->stdev->dev,
+ "peer partition is not NT partition\n");
+ return -ENODEV;
+ }
+
+ sndev->peer_partition = bit - 1;
+ } else {
+ if (ffs(tpart_vec) != fls(tpart_vec)) {
+ dev_err(&sndev->stdev->dev,
+ "ntb driver only supports 1 pair of 1-1 ntb
mapping\n");
+ return -ENODEV;
+ }
+
+ sndev->peer_partition = ffs(tpart_vec) - 1;
+ if (!(part_map && (1 << sndev->peer_partition))) {
+ dev_err(&sndev->stdev->dev,
+ "ntb target partition is not NT partition\n");
+ return -ENODEV;
+ }
+ }
+
+ dev_dbg(&sndev->stdev->dev, "Partition ID %d of %d\n",
+ sndev->self_partition, sndev->stdev->partition_count);
sndev->mmio_ctrl = (void * __iomem)sndev->mmio_ntb +
SWITCHTEC_NTB_REG_CTRL_OFFSET;
@@ -804,6 +841,8 @@ static void switchtec_ntb_init_sndev(struct switchtec_ntb
*sndev)
sndev->mmio_self_ctrl = &sndev->mmio_ctrl[sndev->self_partition];
sndev->mmio_peer_ctrl = &sndev->mmio_ctrl[sndev->peer_partition];
sndev->mmio_self_dbmsg = &sndev->mmio_dbmsg[sndev->self_partition];
+
+ return 0;
}
static int map_bars(int *map, struct ntb_ctrl_regs __iomem *ctrl)
@@ -1135,15 +1174,15 @@ static int switchtec_ntb_add(struct device *dev,
if (stdev->pdev->class != MICROSEMI_NTB_CLASSCODE)
return -ENODEV;
- if (stdev->partition_count != 2)
- dev_warn(dev, "ntb driver only supports 2 partitions\n");
-
sndev = kzalloc_node(sizeof(*sndev), GFP_KERNEL, dev_to_node(dev));
if (!sndev)
return -ENOMEM;
sndev->stdev = stdev;
- switchtec_ntb_init_sndev(sndev);
+ rc = switchtec_ntb_init_sndev(sndev);
+ if (rc)
+ goto free_and_exit;
+
switchtec_ntb_init_mw(sndev);
switchtec_ntb_init_db(sndev);
switchtec_ntb_init_msgs(sndev);
diff --git a/include/linux/switchtec.h b/include/linux/switchtec.h
index 09d73d0d1aa8..d4a7c18b42cf 100644
--- a/include/linux/switchtec.h
+++ b/include/linux/switchtec.h
@@ -168,6 +168,14 @@ struct ntb_info_regs {
u16 reserved1;
u64 ep_map;
u16 requester_id;
+ u16 reserved2;
+ u32 reserved3[4];
+ struct nt_partition_info {
+ u32 xlink_enabled;
+ u32 target_part_low;
+ u32 target_part_high;
+ u32 reserved;
+ } ntp_info[48];
} __packed;
struct part_cfg_regs {
--
2.11.0
