Commit 19645a07 authored by Logan Gunthorpe's avatar Logan Gunthorpe Committed by Jon Mason
Browse files

ntb_transport: Check the number of spads the hardware supports

I'm working on hardware that currently has a limited number of
scratchpad registers and ntb_ndev fails with no clue as to why. I
feel it is better to fail early and provide a reasonable error message
then to fail later on.

The same is done to ntb_perf, but it doesn't currently require enough
spads to actually fail. I've also removed the unused SPAD_MSG and
SPAD_ACK enums so that MAX_SPAD accurately reflects the number of
spads used.
Signed-off-by: default avatarLogan Gunthorpe <>
Acked-by: default avatarDave Jiang <>
Signed-off-by: default avatarJon Mason <>
parent 8b71d285
......@@ -1060,6 +1060,13 @@ static int ntb_transport_probe(struct ntb_client *self, struct ntb_dev *ndev)
int node;
int rc, i;
mw_count = ntb_mw_count(ndev);
if (ntb_spad_count(ndev) < (NUM_MWS + 1 + mw_count * 2)) {
dev_err(&ndev->dev, "Not enough scratch pad registers for %s",
return -EIO;
if (ntb_db_is_unsafe(ndev))
"doorbell is unsafe, proceed anyway...\n");
......@@ -1075,8 +1082,6 @@ static int ntb_transport_probe(struct ntb_client *self, struct ntb_dev *ndev)
nt->ndev = ndev;
mw_count = ntb_mw_count(ndev);
nt->mw_count = mw_count;
nt->mw_vec = kzalloc_node(mw_count * sizeof(*nt->mw_vec),
......@@ -143,8 +143,6 @@ enum {
......@@ -696,6 +694,12 @@ static int perf_probe(struct ntb_client *client, struct ntb_dev *ntb)
int node;
int rc = 0;
if (ntb_spad_count(ntb) < MAX_SPAD) {
dev_err(&ntb->dev, "Not enough scratch pad registers for %s",
return -EIO;
node = dev_to_node(&pdev->dev);
perf = kzalloc_node(sizeof(*perf), GFP_KERNEL, node);
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment