nfp: wait for the NSP resource to appear on boot

The control process (NSP) may take some time to complete its
initialization.  This is not a problem on most servers, but
on very fast-booting machines it may not be ready for operation
when driver probes the device.  There is also a version of the
flash in the wild where NSP tries to train the links as part
of init.  To wait for NSP initialization we should make sure
its resource has already been added to the resource table.
NSP adds itself there as last step of init.

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

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_main.c b/drivers/net/ethernet/netronome/nfp/nfp_main.c
index 424707d41fbdcc12e7c9239e9a7941ec2bed53e4..f8fa63b66739dfcc081b623ff7de717bb5928445 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/nfp_main.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_main.c
@@ -351,6 +351,10 @@ static int nfp_nsp_init(struct pci_dev *pdev, struct nfp_pf *pf)
        struct nfp_nsp *nsp;
        int err;
 
+       err = nfp_resource_wait(pf->cpp, NFP_RESOURCE_NSP, 30);
+       if (err)
+               return err;
+
        nsp = nfp_nsp_open(pf->cpp);
        if (IS_ERR(nsp)) {
                err = PTR_ERR(nsp);

diff --git a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp.h b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp.h
index 1a8d04a1e11327f8ec4411c258469bca728ffb32..3ce51f03126fa76f69c007ed88e76e9ee77bb174 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp.h
+++ b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp.h
@@ -97,6 +97,8 @@ nfp_resource_acquire(struct nfp_cpp *cpp, const char *name);
 
 void nfp_resource_release(struct nfp_resource *res);
 
+int nfp_resource_wait(struct nfp_cpp *cpp, const char *name, unsigned int secs);
+
 u32 nfp_resource_cpp_id(struct nfp_resource *res);
 
 const char *nfp_resource_name(struct nfp_resource *res);

diff --git a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_resource.c b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_resource.c
index 072612263dabe92e76481a14cacebfa0cf513b4a..b1dd13ff282bba0c2cce9b666d4cf822e5160ce1 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_resource.c
+++ b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_resource.c
@@ -249,6 +249,51 @@ void nfp_resource_release(struct nfp_resource *res)
        kfree(res);
 }
 
+/**
+ * nfp_resource_wait() - Wait for resource to appear
+ * @cpp:       NFP CPP handle
+ * @name:      Name of the resource
+ * @secs:      Number of seconds to wait
+ *
+ * Wait for resource to appear in the resource table, grab and release
+ * its lock.  The wait is jiffies-based, don't expect fine granularity.
+ *
+ * Return: 0 on success, errno otherwise.
+ */
+int nfp_resource_wait(struct nfp_cpp *cpp, const char *name, unsigned int secs)
+{
+       unsigned long warn_at = jiffies + NFP_MUTEX_WAIT_FIRST_WARN * HZ;
+       unsigned long err_at = jiffies + secs * HZ;
+       struct nfp_resource *res;
+
+       while (true) {
+               res = nfp_resource_acquire(cpp, name);
+               if (!IS_ERR(res)) {
+                       nfp_resource_release(res);
+                       return 0;
+               }
+
+               if (PTR_ERR(res) != -ENOENT) {
+                       nfp_err(cpp, "error waiting for resource %s: %ld\n",
+                               name, PTR_ERR(res));
+                       return PTR_ERR(res);
+               }
+               if (time_is_before_eq_jiffies(err_at)) {
+                       nfp_err(cpp, "timeout waiting for resource %s\n", name);
+                       return -ETIMEDOUT;
+               }
+               if (time_is_before_eq_jiffies(warn_at)) {
+                       warn_at = jiffies + NFP_MUTEX_WAIT_NEXT_WARN * HZ;
+                       nfp_info(cpp, "waiting for NFP resource %s\n", name);
+               }
+               if (msleep_interruptible(10)) {
+                       nfp_err(cpp, "wait for resource %s interrupted\n",
+                               name);
+                       return -ERESTARTSYS;
+               }
+       }
+}
+
 /**
  * nfp_resource_cpp_id() - Return the cpp_id of a resource handle
  * @res:       NFP Resource handle