kernel/drivers/staging/octeon/ethernet-rgmii.c

   1 /*
   2  * This file is based on code from OCTEON SDK by Cavium Networks.
   3  *
   4  * Copyright (c) 2003-2007 Cavium Networks
   5  *
   6  * This file is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License, Version 2, as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/netdevice.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/phy.h>
  15 #include <linux/ratelimit.h>
  16 #include <net/dst.h>
  17
  18 #include <asm/octeon/octeon.h>
  19
  20 #include "ethernet-defines.h"
  21 #include "octeon-ethernet.h"
  22 #include "ethernet-util.h"
  23 #include "ethernet-mdio.h"
  24
  25 #include <asm/octeon/cvmx-helper.h>
  26
  27 #include <asm/octeon/cvmx-ipd-defs.h>
  28 #include <asm/octeon/cvmx-npi-defs.h>
  29 #include <asm/octeon/cvmx-gmxx-defs.h>
  30
  31 static DEFINE_SPINLOCK(global_register_lock);
  32
  33 static int number_rgmii_ports;
  34
  35 static void cvm_oct_set_hw_preamble(struct octeon_ethernet *priv, bool enable)
  36 {
  37         union cvmx_gmxx_rxx_frm_ctl gmxx_rxx_frm_ctl;
  38         union cvmx_ipd_sub_port_fcs ipd_sub_port_fcs;
  39         union cvmx_gmxx_rxx_int_reg gmxx_rxx_int_reg;
  40         int interface = INTERFACE(priv->port);
  41         int index = INDEX(priv->port);
  42
  43         /* Set preamble checking. */
  44         gmxx_rxx_frm_ctl.u64 = cvmx_read_csr(CVMX_GMXX_RXX_FRM_CTL(index,
  45                                                                    interface));
  46         gmxx_rxx_frm_ctl.s.pre_chk = enable;
  47         cvmx_write_csr(CVMX_GMXX_RXX_FRM_CTL(index, interface),
  48                        gmxx_rxx_frm_ctl.u64);
  49
  50         /* Set FCS stripping. */
  51         ipd_sub_port_fcs.u64 = cvmx_read_csr(CVMX_IPD_SUB_PORT_FCS);
  52         if (enable)
  53                 ipd_sub_port_fcs.s.port_bit |= 1ull << priv->port;
  54         else
  55                 ipd_sub_port_fcs.s.port_bit &=
  56                                         0xffffffffull ^ (1ull << priv->port);
  57         cvmx_write_csr(CVMX_IPD_SUB_PORT_FCS, ipd_sub_port_fcs.u64);
  58
  59         /* Clear any error bits. */
  60         gmxx_rxx_int_reg.u64 = cvmx_read_csr(CVMX_GMXX_RXX_INT_REG(index,
  61                                                                    interface));
  62         cvmx_write_csr(CVMX_GMXX_RXX_INT_REG(index, interface),
  63                        gmxx_rxx_int_reg.u64);
  64 }
  65
  66 static void cvm_oct_rgmii_poll(struct net_device *dev)
  67 {
  68         struct octeon_ethernet *priv = netdev_priv(dev);
  69         unsigned long flags = 0;
  70         cvmx_helper_link_info_t link_info;
  71         int use_global_register_lock = (priv->phydev == NULL);
  72
  73         BUG_ON(in_interrupt());
  74         if (use_global_register_lock) {
  75                 /*
  76                  * Take the global register lock since we are going to
  77                  * touch registers that affect more than one port.
  78                  */
  79                 spin_lock_irqsave(&global_register_lock, flags);
  80         } else {
  81                 mutex_lock(&priv->phydev->bus->mdio_lock);
  82         }
  83
  84         link_info = cvmx_helper_link_get(priv->port);
  85         if (link_info.u64 == priv->link_info) {
  86                 if (link_info.s.speed == 10) {
  87                         /*
  88                          * Read the GMXX_RXX_INT_REG[PCTERR] bit and
  89                          * see if we are getting preamble errors.
  90                          */
  91                         int interface = INTERFACE(priv->port);
  92                         int index = INDEX(priv->port);
  93                         union cvmx_gmxx_rxx_int_reg gmxx_rxx_int_reg;
  94
  95                         gmxx_rxx_int_reg.u64 =
  96                             cvmx_read_csr(CVMX_GMXX_RXX_INT_REG
  97                                           (index, interface));
  98                         if (gmxx_rxx_int_reg.s.pcterr) {
  99                                 /*
 100                                  * We are getting preamble errors at
 101                                  * 10Mbps.  Most likely the PHY is
 102                                  * giving us packets with mis aligned
 103                                  * preambles. In order to get these
 104                                  * packets we need to disable preamble
 105                                  * checking and do it in software.
 106                                  */
 107                                 cvm_oct_set_hw_preamble(priv, false);
 108                                 printk_ratelimited("%s: Using 10Mbps with software preamble removal\n",
 109                                                    dev->name);
 110                         }
 111                 }
 112
 113                 if (use_global_register_lock)
 114                         spin_unlock_irqrestore(&global_register_lock, flags);
 115                 else
 116                         mutex_unlock(&priv->phydev->bus->mdio_lock);
 117                 return;
 118         }
 119
 120         /* Since the 10Mbps preamble workaround is allowed we need to enable
 121          * preamble checking, FCS stripping, and clear error bits on
 122          * every speed change. If errors occur during 10Mbps operation
 123          * the above code will change this stuff
 124          */
 125         cvm_oct_set_hw_preamble(priv, true);
 126
 127         if (priv->phydev == NULL) {
 128                 link_info = cvmx_helper_link_autoconf(priv->port);
 129                 priv->link_info = link_info.u64;
 130         }
 131
 132         if (use_global_register_lock)
 133                 spin_unlock_irqrestore(&global_register_lock, flags);
 134         else
 135                 mutex_unlock(&priv->phydev->bus->mdio_lock);
 136
 137         if (priv->phydev == NULL) {
 138                 /* Tell core. */
 139                 if (link_info.s.link_up) {
 140                         if (!netif_carrier_ok(dev))
 141                                 netif_carrier_on(dev);
 142                 } else if (netif_carrier_ok(dev)) {
 143                         netif_carrier_off(dev);
 144                 }
 145                 cvm_oct_note_carrier(priv, link_info);
 146         }
 147 }
 148
 149 static int cmv_oct_rgmii_gmx_interrupt(int interface)
 150 {
 151         int index;
 152         int count = 0;
 153
 154         /* Loop through every port of this interface */
 155         for (index = 0;
 156              index < cvmx_helper_ports_on_interface(interface);
 157              index++) {
 158                 union cvmx_gmxx_rxx_int_reg gmx_rx_int_reg;
 159
 160                 /* Read the GMX interrupt status bits */
 161                 gmx_rx_int_reg.u64 = cvmx_read_csr(CVMX_GMXX_RXX_INT_REG
 162                                           (index, interface));
 163                 gmx_rx_int_reg.u64 &= cvmx_read_csr(CVMX_GMXX_RXX_INT_EN
 164                                           (index, interface));
 165
 166                 /* Poll the port if inband status changed */
 167                 if (gmx_rx_int_reg.s.phy_dupx || gmx_rx_int_reg.s.phy_link ||
 168                     gmx_rx_int_reg.s.phy_spd) {
 169                         struct net_device *dev =
 170                                     cvm_oct_device[cvmx_helper_get_ipd_port
 171                                                    (interface, index)];
 172                         struct octeon_ethernet *priv = netdev_priv(dev);
 173
 174                         if (dev && !atomic_read(&cvm_oct_poll_queue_stopping))
 175                                 queue_work(cvm_oct_poll_queue,
 176                                            &priv->port_work);
 177
 178                         gmx_rx_int_reg.u64 = 0;
 179                         gmx_rx_int_reg.s.phy_dupx = 1;
 180                         gmx_rx_int_reg.s.phy_link = 1;
 181                         gmx_rx_int_reg.s.phy_spd = 1;
 182                         cvmx_write_csr(CVMX_GMXX_RXX_INT_REG(index, interface),
 183                                        gmx_rx_int_reg.u64);
 184                         count++;
 185                 }
 186         }
 187         return count;
 188 }
 189
 190 static irqreturn_t cvm_oct_rgmii_rml_interrupt(int cpl, void *dev_id)
 191 {
 192         union cvmx_npi_rsl_int_blocks rsl_int_blocks;
 193         int count = 0;
 194
 195         rsl_int_blocks.u64 = cvmx_read_csr(CVMX_NPI_RSL_INT_BLOCKS);
 196
 197         /* Check and see if this interrupt was caused by the GMX0 block */
 198         if (rsl_int_blocks.s.gmx0)
 199                 count += cmv_oct_rgmii_gmx_interrupt(0);
 200
 201         /* Check and see if this interrupt was caused by the GMX1 block */
 202         if (rsl_int_blocks.s.gmx1)
 203                 count += cmv_oct_rgmii_gmx_interrupt(1);
 204
 205         return count ? IRQ_HANDLED : IRQ_NONE;
 206 }
 207
 208 int cvm_oct_rgmii_open(struct net_device *dev)
 209 {
 210         return cvm_oct_common_open(dev, cvm_oct_rgmii_poll);
 211 }
 212
 213 static void cvm_oct_rgmii_immediate_poll(struct work_struct *work)
 214 {
 215         struct octeon_ethernet *priv =
 216                 container_of(work, struct octeon_ethernet, port_work);
 217         cvm_oct_rgmii_poll(cvm_oct_device[priv->port]);
 218 }
 219
 220 int cvm_oct_rgmii_init(struct net_device *dev)
 221 {
 222         struct octeon_ethernet *priv = netdev_priv(dev);
 223         int r;
 224
 225         cvm_oct_common_init(dev);
 226         INIT_WORK(&priv->port_work, cvm_oct_rgmii_immediate_poll);
 227         /*
 228          * Due to GMX errata in CN3XXX series chips, it is necessary
 229          * to take the link down immediately when the PHY changes
 230          * state. In order to do this we call the poll function every
 231          * time the RGMII inband status changes.  This may cause
 232          * problems if the PHY doesn't implement inband status
 233          * properly.
 234          */
 235         if (number_rgmii_ports == 0) {
 236                 r = request_irq(OCTEON_IRQ_RML, cvm_oct_rgmii_rml_interrupt,
 237                                 IRQF_SHARED, "RGMII", &number_rgmii_ports);
 238                 if (r != 0)
 239                         return r;
 240         }
 241         number_rgmii_ports++;
 242
 243         /*
 244          * Only true RGMII ports need to be polled. In GMII mode, port
 245          * 0 is really a RGMII port.
 246          */
 247         if (((priv->imode == CVMX_HELPER_INTERFACE_MODE_GMII)
 248              && (priv->port == 0))
 249             || (priv->imode == CVMX_HELPER_INTERFACE_MODE_RGMII)) {
 250
 251                 if (!octeon_is_simulation()) {
 252
 253                         union cvmx_gmxx_rxx_int_en gmx_rx_int_en;
 254                         int interface = INTERFACE(priv->port);
 255                         int index = INDEX(priv->port);
 256
 257                         /*
 258                          * Enable interrupts on inband status changes
 259                          * for this port.
 260                          */
 261                         gmx_rx_int_en.u64 = 0;
 262                         gmx_rx_int_en.s.phy_dupx = 1;
 263                         gmx_rx_int_en.s.phy_link = 1;
 264                         gmx_rx_int_en.s.phy_spd = 1;
 265                         cvmx_write_csr(CVMX_GMXX_RXX_INT_EN(index, interface),
 266                                        gmx_rx_int_en.u64);
 267                 }
 268         }
 269
 270         return 0;
 271 }
 272
 273 void cvm_oct_rgmii_uninit(struct net_device *dev)
 274 {
 275         struct octeon_ethernet *priv = netdev_priv(dev);
 276
 277         cvm_oct_common_uninit(dev);
 278
 279         /*
 280          * Only true RGMII ports need to be polled. In GMII mode, port
 281          * 0 is really a RGMII port.
 282          */
 283         if (((priv->imode == CVMX_HELPER_INTERFACE_MODE_GMII)
 284              && (priv->port == 0))
 285             || (priv->imode == CVMX_HELPER_INTERFACE_MODE_RGMII)) {
 286
 287                 if (!octeon_is_simulation()) {
 288
 289                         union cvmx_gmxx_rxx_int_en gmx_rx_int_en;
 290                         int interface = INTERFACE(priv->port);
 291                         int index = INDEX(priv->port);
 292
 293                         /*
 294                          * Disable interrupts on inband status changes
 295                          * for this port.
 296                          */
 297                         gmx_rx_int_en.u64 =
 298                             cvmx_read_csr(CVMX_GMXX_RXX_INT_EN
 299                                           (index, interface));
 300                         gmx_rx_int_en.s.phy_dupx = 0;
 301                         gmx_rx_int_en.s.phy_link = 0;
 302                         gmx_rx_int_en.s.phy_spd = 0;
 303                         cvmx_write_csr(CVMX_GMXX_RXX_INT_EN(index, interface),
 304                                        gmx_rx_int_en.u64);
 305                 }
 306         }
 307
 308         /* Remove the interrupt handler when the last port is removed. */
 309         number_rgmii_ports--;
 310         if (number_rgmii_ports == 0)
 311                 free_irq(OCTEON_IRQ_RML, &number_rgmii_ports);
 312         cancel_work_sync(&priv->port_work);
 313 }