nfp: wait for board state before talking to the NSP

Board state informs us which low-level initialization stages the card
has completed.  We should wait for the card to be fully initialized
before trying to communicate with it, not only before we configure
passing traffic.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 43 insertions, 0 deletions

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_main.c b/drivers/net/ethernet/netronome/nfp/nfp_main.c
index f055b1774d65..424707d41fbd 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_main.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_main.c
@@ -74,6 +74,45 @@ static const struct pci_device_id nfp_pci_device_ids[] = {
 };
 MODULE_DEVICE_TABLE(pci, nfp_pci_device_ids);
 
+static bool nfp_board_ready(struct nfp_pf *pf)
+{
+	const char *cp;
+	long state;
+	int err;
+
+	cp = nfp_hwinfo_lookup(pf->hwinfo, "board.state");
+	if (!cp)
+		return false;
+
+	err = kstrtol(cp, 0, &state);
+	if (err < 0)
+		return false;
+
+	return state == 15;
+}
+
+static int nfp_pf_board_state_wait(struct nfp_pf *pf)
+{
+	const unsigned long wait_until = jiffies + 10 * HZ;
+
+	while (!nfp_board_ready(pf)) {
+		if (time_is_before_eq_jiffies(wait_until)) {
+			nfp_err(pf->cpp, "NFP board initialization timeout\n");
+			return -EINVAL;
+		}
+
+		nfp_info(pf->cpp, "waiting for board initialization\n");
+		if (msleep_interruptible(500))
+			return -ERESTARTSYS;
+
+		/* Refresh cached information */
+		kfree(pf->hwinfo);
+		pf->hwinfo = nfp_hwinfo_read(pf->cpp);
+	}
+
+	return 0;
+}
+
 static int nfp_pcie_sriov_read_nfd_limit(struct nfp_pf *pf)
 {
 	int err;
@@ -425,6 +464,10 @@ static int nfp_pci_probe(struct pci_dev *pdev,
 		 nfp_hwinfo_lookup(pf->hwinfo, "assembly.revision"),
 		 nfp_hwinfo_lookup(pf->hwinfo, "cpld.version"));
 
+	err = nfp_pf_board_state_wait(pf);
+	if (err)
+		goto err_hwinfo_free;
+
 	err = devlink_register(devlink, &pdev->dev);
 	if (err)
 		goto err_hwinfo_free;