netdev: octeon_mgmt: Add hardware timestamp support.
authorChad Reese <kreese@caviumnetworks.com>
Tue, 21 Aug 2012 18:45:07 +0000 (11:45 -0700)
committerDavid Daney <david.daney@cavium.com>
Fri, 31 Aug 2012 18:49:18 +0000 (11:49 -0700)
Octeon cn6XXX models have timestamp support on the mgmt ports, so hook
it up.

Signed-off-by: Chad Reese <kreese@caviumnetworks.com>
Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/octeon/octeon_mgmt.c

index c4df1ab13b693d2a46fed28c1d0c9d1fcee1b577..687a6a0c7147626cf296e63e2a573511734208c4 100644 (file)
@@ -10,6 +10,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/etherdevice.h>
 #include <linux/capability.h>
+#include <linux/net_tstamp.h>
 #include <linux/interrupt.h>
 #include <linux/netdevice.h>
 #include <linux/spinlock.h>
@@ -114,6 +115,7 @@ struct octeon_mgmt {
        u64 agl_prt_ctl;
        int port;
        int irq;
+       bool has_rx_tstamp;
        u64 *tx_ring;
        dma_addr_t tx_ring_handle;
        unsigned int tx_next;
@@ -238,6 +240,28 @@ static void octeon_mgmt_rx_fill_ring(struct net_device *netdev)
        }
 }
 
+static ktime_t ptp_to_ktime(u64 ptptime)
+{
+       ktime_t ktimebase;
+       u64 ptpbase;
+       unsigned long flags;
+
+       local_irq_save(flags);
+       /* Fill the icache with the code */
+       ktime_get_real();
+       /* Flush all pending operations */
+       mb();
+       /* Read the time and PTP clock as close together as
+        * possible. It is important that this sequence take the same
+        * amount of time to reduce jitter
+        */
+       ktimebase = ktime_get_real();
+       ptpbase = cvmx_read_csr(CVMX_MIO_PTP_CLOCK_HI);
+       local_irq_restore(flags);
+
+       return ktime_sub_ns(ktimebase, ptpbase - ptptime);
+}
+
 static void octeon_mgmt_clean_tx_buffers(struct octeon_mgmt *p)
 {
        union cvmx_mixx_orcnt mix_orcnt;
@@ -277,6 +301,20 @@ static void octeon_mgmt_clean_tx_buffers(struct octeon_mgmt *p)
 
                dma_unmap_single(p->dev, re.s.addr, re.s.len,
                                 DMA_TO_DEVICE);
+
+               /* Read the hardware TX timestamp if one was recorded */
+               if (unlikely(re.s.tstamp)) {
+                       struct skb_shared_hwtstamps ts;
+                       /* Read the timestamp */
+                       u64 ns = cvmx_read_csr(CVMX_MIXX_TSTAMP(p->port));
+                       /* Remove the timestamp from the FIFO */
+                       cvmx_write_csr(CVMX_MIXX_TSCTL(p->port), 0);
+                       /* Tell the kernel about the timestamp */
+                       ts.syststamp = ptp_to_ktime(ns);
+                       ts.hwtstamp = ns_to_ktime(ns);
+                       skb_tstamp_tx(skb, &ts);
+               }
+
                dev_kfree_skb_any(skb);
                cleaned++;
 
@@ -377,6 +415,16 @@ static int octeon_mgmt_receive_one(struct octeon_mgmt *p)
                /* A good packet, send it up. */
                skb_put(skb, re.s.len);
 good:
+               /* Process the RX timestamp if it was recorded */
+               if (p->has_rx_tstamp) {
+                       /* The first 8 bytes are the timestamp */
+                       u64 ns = *(u64 *)skb->data;
+                       struct skb_shared_hwtstamps *ts;
+                       ts = skb_hwtstamps(skb);
+                       ts->hwtstamp = ns_to_ktime(ns);
+                       ts->syststamp = ptp_to_ktime(ns);
+                       __skb_pull(skb, 8);
+               }
                skb->protocol = eth_type_trans(skb, netdev);
                netdev->stats.rx_packets++;
                netdev->stats.rx_bytes += skb->len;
@@ -661,18 +709,114 @@ static irqreturn_t octeon_mgmt_interrupt(int cpl, void *dev_id)
        return IRQ_HANDLED;
 }
 
-static int octeon_mgmt_ioctl(struct net_device *netdev,
-                            struct ifreq *rq, int cmd)
+static int octeon_mgmt_ioctl_hwtstamp(struct net_device *netdev,
+                                     struct ifreq *rq, int cmd)
 {
        struct octeon_mgmt *p = netdev_priv(netdev);
+       struct hwtstamp_config config;
+       union cvmx_mio_ptp_clock_cfg ptp;
+       union cvmx_agl_gmx_rxx_frm_ctl rxx_frm_ctl;
+       bool have_hw_timestamps = false;
+
+       if (copy_from_user(&config, rq->ifr_data, sizeof(config)))
+               return -EFAULT;
 
-       if (!netif_running(netdev))
+       if (config.flags) /* reserved for future extensions */
                return -EINVAL;
 
-       if (!p->phydev)
+       /* Check the status of hardware for tiemstamps */
+       if (OCTEON_IS_MODEL(OCTEON_CN6XXX)) {
+               /* Get the current state of the PTP clock */
+               ptp.u64 = cvmx_read_csr(CVMX_MIO_PTP_CLOCK_CFG);
+               if (!ptp.s.ext_clk_en) {
+                       /* The clock has not been configured to use an
+                        * external source.  Program it to use the main clock
+                        * reference.
+                        */
+                       u64 clock_comp = (NSEC_PER_SEC << 32) / octeon_get_io_clock_rate();
+                       if (!ptp.s.ptp_en)
+                               cvmx_write_csr(CVMX_MIO_PTP_CLOCK_COMP, clock_comp);
+                       pr_info("PTP Clock: Using sclk reference at %lld Hz\n",
+                               (NSEC_PER_SEC << 32) / clock_comp);
+               } else {
+                       /* The clock is already programmed to use a GPIO */
+                       u64 clock_comp = cvmx_read_csr(CVMX_MIO_PTP_CLOCK_COMP);
+                       pr_info("PTP Clock: Using GPIO %d at %lld Hz\n",
+                               ptp.s.ext_clk_in,
+                               (NSEC_PER_SEC << 32) / clock_comp);
+               }
+
+               /* Enable the clock if it wasn't done already */
+               if (!ptp.s.ptp_en) {
+                       ptp.s.ptp_en = 1;
+                       cvmx_write_csr(CVMX_MIO_PTP_CLOCK_CFG, ptp.u64);
+               }
+               have_hw_timestamps = true;
+       }
+
+       if (!have_hw_timestamps)
                return -EINVAL;
 
-       return phy_mii_ioctl(p->phydev, rq, cmd);
+       switch (config.tx_type) {
+       case HWTSTAMP_TX_OFF:
+       case HWTSTAMP_TX_ON:
+               break;
+       default:
+               return -ERANGE;
+       }
+
+       switch (config.rx_filter) {
+       case HWTSTAMP_FILTER_NONE:
+               p->has_rx_tstamp = false;
+               rxx_frm_ctl.u64 = cvmx_read_csr(p->agl + AGL_GMX_RX_FRM_CTL);
+               rxx_frm_ctl.s.ptp_mode = 0;
+               cvmx_write_csr(p->agl + AGL_GMX_RX_FRM_CTL, rxx_frm_ctl.u64);
+               break;
+       case HWTSTAMP_FILTER_ALL:
+       case HWTSTAMP_FILTER_SOME:
+       case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
+       case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
+       case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
+       case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
+       case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
+       case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
+       case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
+       case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
+       case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
+       case HWTSTAMP_FILTER_PTP_V2_EVENT:
+       case HWTSTAMP_FILTER_PTP_V2_SYNC:
+       case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+               p->has_rx_tstamp = have_hw_timestamps;
+               config.rx_filter = HWTSTAMP_FILTER_ALL;
+               if (p->has_rx_tstamp) {
+                       rxx_frm_ctl.u64 = cvmx_read_csr(p->agl + AGL_GMX_RX_FRM_CTL);
+                       rxx_frm_ctl.s.ptp_mode = 1;
+                       cvmx_write_csr(p->agl + AGL_GMX_RX_FRM_CTL, rxx_frm_ctl.u64);
+               }
+               break;
+       default:
+               return -ERANGE;
+       }
+
+       if (copy_to_user(rq->ifr_data, &config, sizeof(config)))
+               return -EFAULT;
+
+       return 0;
+}
+
+static int octeon_mgmt_ioctl(struct net_device *netdev,
+                            struct ifreq *rq, int cmd)
+{
+       struct octeon_mgmt *p = netdev_priv(netdev);
+
+       switch (cmd) {
+       case SIOCSHWTSTAMP:
+               return octeon_mgmt_ioctl_hwtstamp(netdev, rq, cmd);
+       default:
+               if (p->phydev)
+                       return phy_mii_ioctl(p->phydev, rq, cmd);
+               return -EINVAL;
+       }
 }
 
 static void octeon_mgmt_disable_link(struct octeon_mgmt *p)
@@ -1052,6 +1196,7 @@ static int octeon_mgmt_open(struct net_device *netdev)
        /* Enable packet I/O. */
 
        rxx_frm_ctl.u64 = 0;
+       rxx_frm_ctl.s.ptp_mode = p->has_rx_tstamp ? 1 : 0;
        rxx_frm_ctl.s.pre_align = 1;
        /*
         * When set, disables the length check for non-min sized pkts
@@ -1155,6 +1300,7 @@ static int octeon_mgmt_xmit(struct sk_buff *skb, struct net_device *netdev)
        int rv = NETDEV_TX_BUSY;
 
        re.d64 = 0;
+       re.s.tstamp = ((skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) != 0);
        re.s.len = skb->len;
        re.s.addr = dma_map_single(p->dev, skb->data,
                                   skb->len,
@@ -1293,6 +1439,7 @@ static int __devinit octeon_mgmt_probe(struct platform_device *pdev)
 
        p->netdev = netdev;
        p->dev = &pdev->dev;
+       p->has_rx_tstamp = false;
 
        data = of_get_property(pdev->dev.of_node, "cell-index", &len);
        if (data && len == sizeof(*data)) {