summaryrefslogtreecommitdiffstats
path: root/drivers/net/ethernet/netronome
diff options
context:
space:
mode:
authorJakub Kicinski <jakub.kicinski@netronome.com>2016-04-16 11:25:54 +0100
committerDavid S. Miller <davem@davemloft.net>2016-04-16 22:34:40 -0400
commit3d780b926a12dd798417446d733d457f1be1cc73 (patch)
tree6065a2d9bfe45518f6f8ce4e4425fc2460a70b22 /drivers/net/ethernet/netronome
parent180012dc05e565260a25696767c8f5b2df5fc50e (diff)
downloadblackbird-op-linux-3d780b926a12dd798417446d733d457f1be1cc73.tar.gz
blackbird-op-linux-3d780b926a12dd798417446d733d457f1be1cc73.zip
nfp: add async reconfiguration mechanism
Some callers of nfp_net_reconfig() are in atomic context so we used to busy wait for commands to complete. In worst case scenario that means locking up a core for up to 5 seconds when a command times out. Lets add a timer-based mechanism of asynchronously checking whether reconfiguration completed successfully for atomic callers to use. Non-atomic callers can now just sleep. The approach taken is quite simple because (1) synchronous reconfigurations always happen under RTNL (or before device is registered); (2) we can coalesce pending reconfigs. There is no need for request queues, timer which eventually takes a look at reconfiguration result to report errors is good enough. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/netronome')
-rw-r--r--drivers/net/ethernet/netronome/nfp/nfp_net.h12
-rw-r--r--drivers/net/ethernet/netronome/nfp/nfp_net_common.c172
2 files changed, 157 insertions, 27 deletions
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net.h b/drivers/net/ethernet/netronome/nfp/nfp_net.h
index 3d53fcf323eb..e744acc18ef4 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net.h
@@ -59,8 +59,8 @@
netdev_warn((nn)->netdev, fmt, ## args); \
} while (0)
-/* Max time to wait for NFP to respond on updates (in ms) */
-#define NFP_NET_POLL_TIMEOUT 5000
+/* Max time to wait for NFP to respond on updates (in seconds) */
+#define NFP_NET_POLL_TIMEOUT 5
/* Bar allocation */
#define NFP_NET_CRTL_BAR 0
@@ -447,6 +447,10 @@ static inline bool nfp_net_fw_ver_eq(struct nfp_net_fw_version *fw_ver,
* @shared_name: Name for shared interrupt
* @me_freq_mhz: ME clock_freq (MHz)
* @reconfig_lock: Protects HW reconfiguration request regs/machinery
+ * @reconfig_posted: Pending reconfig bits coming from async sources
+ * @reconfig_timer_active: Timer for reading reconfiguration results is pending
+ * @reconfig_sync_present: Some thread is performing synchronous reconfig
+ * @reconfig_timer: Timer for async reading of reconfig results
* @link_up: Is the link up?
* @link_status_lock: Protects @link_up and ensures atomicity with BAR reading
* @rx_coalesce_usecs: RX interrupt moderation usecs delay parameter
@@ -531,6 +535,10 @@ struct nfp_net {
spinlock_t link_status_lock;
spinlock_t reconfig_lock;
+ u32 reconfig_posted;
+ bool reconfig_timer_active;
+ bool reconfig_sync_present;
+ struct timer_list reconfig_timer;
u32 rx_coalesce_usecs;
u32 rx_coalesce_max_frames;
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 5235e86eb684..fa47c14c743a 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -80,6 +80,116 @@ void nfp_net_get_fw_version(struct nfp_net_fw_version *fw_ver,
put_unaligned_le32(reg, fw_ver);
}
+/* Firmware reconfig
+ *
+ * Firmware reconfig may take a while so we have two versions of it -
+ * synchronous and asynchronous (posted). All synchronous callers are holding
+ * RTNL so we don't have to worry about serializing them.
+ */
+static void nfp_net_reconfig_start(struct nfp_net *nn, u32 update)
+{
+ nn_writel(nn, NFP_NET_CFG_UPDATE, update);
+ /* ensure update is written before pinging HW */
+ nn_pci_flush(nn);
+ nfp_qcp_wr_ptr_add(nn->qcp_cfg, 1);
+}
+
+/* Pass 0 as update to run posted reconfigs. */
+static void nfp_net_reconfig_start_async(struct nfp_net *nn, u32 update)
+{
+ update |= nn->reconfig_posted;
+ nn->reconfig_posted = 0;
+
+ nfp_net_reconfig_start(nn, update);
+
+ nn->reconfig_timer_active = true;
+ mod_timer(&nn->reconfig_timer, jiffies + NFP_NET_POLL_TIMEOUT * HZ);
+}
+
+static bool nfp_net_reconfig_check_done(struct nfp_net *nn, bool last_check)
+{
+ u32 reg;
+
+ reg = nn_readl(nn, NFP_NET_CFG_UPDATE);
+ if (reg == 0)
+ return true;
+ if (reg & NFP_NET_CFG_UPDATE_ERR) {
+ nn_err(nn, "Reconfig error: 0x%08x\n", reg);
+ return true;
+ } else if (last_check) {
+ nn_err(nn, "Reconfig timeout: 0x%08x\n", reg);
+ return true;
+ }
+
+ return false;
+}
+
+static int nfp_net_reconfig_wait(struct nfp_net *nn, unsigned long deadline)
+{
+ bool timed_out = false;
+
+ /* Poll update field, waiting for NFP to ack the config */
+ while (!nfp_net_reconfig_check_done(nn, timed_out)) {
+ msleep(1);
+ timed_out = time_is_before_eq_jiffies(deadline);
+ }
+
+ if (nn_readl(nn, NFP_NET_CFG_UPDATE) & NFP_NET_CFG_UPDATE_ERR)
+ return -EIO;
+
+ return timed_out ? -EIO : 0;
+}
+
+static void nfp_net_reconfig_timer(unsigned long data)
+{
+ struct nfp_net *nn = (void *)data;
+
+ spin_lock_bh(&nn->reconfig_lock);
+
+ nn->reconfig_timer_active = false;
+
+ /* If sync caller is present it will take over from us */
+ if (nn->reconfig_sync_present)
+ goto done;
+
+ /* Read reconfig status and report errors */
+ nfp_net_reconfig_check_done(nn, true);
+
+ if (nn->reconfig_posted)
+ nfp_net_reconfig_start_async(nn, 0);
+done:
+ spin_unlock_bh(&nn->reconfig_lock);
+}
+
+/**
+ * nfp_net_reconfig_post() - Post async reconfig request
+ * @nn: NFP Net device to reconfigure
+ * @update: The value for the update field in the BAR config
+ *
+ * Record FW reconfiguration request. Reconfiguration will be kicked off
+ * whenever reconfiguration machinery is idle. Multiple requests can be
+ * merged together!
+ */
+static void nfp_net_reconfig_post(struct nfp_net *nn, u32 update)
+{
+ spin_lock_bh(&nn->reconfig_lock);
+
+ /* Sync caller will kick off async reconf when it's done, just post */
+ if (nn->reconfig_sync_present) {
+ nn->reconfig_posted |= update;
+ goto done;
+ }
+
+ /* Opportunistically check if the previous command is done */
+ if (!nn->reconfig_timer_active ||
+ nfp_net_reconfig_check_done(nn, false))
+ nfp_net_reconfig_start_async(nn, update);
+ else
+ nn->reconfig_posted |= update;
+done:
+ spin_unlock_bh(&nn->reconfig_lock);
+}
+
/**
* nfp_net_reconfig() - Reconfigure the firmware
* @nn: NFP Net device to reconfigure
@@ -93,35 +203,45 @@ void nfp_net_get_fw_version(struct nfp_net_fw_version *fw_ver,
*/
int nfp_net_reconfig(struct nfp_net *nn, u32 update)
{
- int cnt, ret = 0;
- u32 new;
+ bool cancelled_timer = false;
+ u32 pre_posted_requests;
+ int ret;
spin_lock_bh(&nn->reconfig_lock);
- nn_writel(nn, NFP_NET_CFG_UPDATE, update);
- /* ensure update is written before pinging HW */
- nn_pci_flush(nn);
- nfp_qcp_wr_ptr_add(nn->qcp_cfg, 1);
+ nn->reconfig_sync_present = true;
- /* Poll update field, waiting for NFP to ack the config */
- for (cnt = 0; ; cnt++) {
- new = nn_readl(nn, NFP_NET_CFG_UPDATE);
- if (new == 0)
- break;
- if (new & NFP_NET_CFG_UPDATE_ERR) {
- nn_err(nn, "Reconfig error: 0x%08x\n", new);
- ret = -EIO;
- break;
- } else if (cnt >= NFP_NET_POLL_TIMEOUT) {
- nn_err(nn, "Reconfig timeout for 0x%08x after %dms\n",
- update, cnt);
- ret = -EIO;
- break;
- }
- mdelay(1);
+ if (nn->reconfig_timer_active) {
+ del_timer(&nn->reconfig_timer);
+ nn->reconfig_timer_active = false;
+ cancelled_timer = true;
+ }
+ pre_posted_requests = nn->reconfig_posted;
+ nn->reconfig_posted = 0;
+
+ spin_unlock_bh(&nn->reconfig_lock);
+
+ if (cancelled_timer)
+ nfp_net_reconfig_wait(nn, nn->reconfig_timer.expires);
+
+ /* Run the posted reconfigs which were issued before we started */
+ if (pre_posted_requests) {
+ nfp_net_reconfig_start(nn, pre_posted_requests);
+ nfp_net_reconfig_wait(nn, jiffies + HZ * NFP_NET_POLL_TIMEOUT);
}
+ nfp_net_reconfig_start(nn, update);
+ ret = nfp_net_reconfig_wait(nn, jiffies + HZ * NFP_NET_POLL_TIMEOUT);
+
+ spin_lock_bh(&nn->reconfig_lock);
+
+ if (nn->reconfig_posted)
+ nfp_net_reconfig_start_async(nn, 0);
+
+ nn->reconfig_sync_present = false;
+
spin_unlock_bh(&nn->reconfig_lock);
+
return ret;
}
@@ -2096,8 +2216,7 @@ static void nfp_net_set_rx_mode(struct net_device *netdev)
return;
nn_writel(nn, NFP_NET_CFG_CTRL, new_ctrl);
- if (nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_GEN))
- return;
+ nfp_net_reconfig_post(nn, NFP_NET_CFG_UPDATE_GEN);
nn->ctrl = new_ctrl;
}
@@ -2405,7 +2524,7 @@ static void nfp_net_set_vxlan_port(struct nfp_net *nn, int idx, __be16 port)
be16_to_cpu(nn->vxlan_ports[i + 1]) << 16 |
be16_to_cpu(nn->vxlan_ports[i]));
- nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_VXLAN);
+ nfp_net_reconfig_post(nn, NFP_NET_CFG_UPDATE_VXLAN);
}
/**
@@ -2551,6 +2670,9 @@ struct nfp_net *nfp_net_netdev_alloc(struct pci_dev *pdev,
spin_lock_init(&nn->reconfig_lock);
spin_lock_init(&nn->link_status_lock);
+ setup_timer(&nn->reconfig_timer,
+ nfp_net_reconfig_timer, (unsigned long)nn);
+
return nn;
}
OpenPOWER on IntegriCloud