/****************************************************************************
 * Driver for Solarflare network controllers and boards
 * Copyright 2007-2011 Solarflare Communications Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation, incorporated herein by reference.
 */

#include <linux/delay.h>
#include <linux/rtnetlink.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include "efx.h"
#include "mdio_10g.h"
#include "nic.h"
#include "phy.h"
#include "workarounds.h"

/* We expect these MMDs to be in the package. */
#define TENXPRESS_REQUIRED_DEVS (MDIO_DEVS_PMAPMD       | \
                                 MDIO_DEVS_PCS          | \
                                 MDIO_DEVS_PHYXS        | \
                                 MDIO_DEVS_AN)

#define SFX7101_LOOPBACKS ((1 << LOOPBACK_PHYXS) |      \
                           (1 << LOOPBACK_PCS) |        \
                           (1 << LOOPBACK_PMAPMD) |     \
                           (1 << LOOPBACK_PHYXS_WS))

/* We complain if we fail to see the link partner as 10G capable this many
 * times in a row (must be > 1 as sampling the autoneg. registers is racy)
 */
#define MAX_BAD_LP_TRIES        (5)

/* Extended control register */
#define PMA_PMD_XCONTROL_REG    49152
#define PMA_PMD_EXT_GMII_EN_LBN 1
#define PMA_PMD_EXT_GMII_EN_WIDTH 1
#define PMA_PMD_EXT_CLK_OUT_LBN 2
#define PMA_PMD_EXT_CLK_OUT_WIDTH 1
#define PMA_PMD_LNPGA_POWERDOWN_LBN 8
#define PMA_PMD_LNPGA_POWERDOWN_WIDTH 1
#define PMA_PMD_EXT_CLK312_WIDTH 1
#define PMA_PMD_EXT_LPOWER_LBN  12
#define PMA_PMD_EXT_LPOWER_WIDTH 1
#define PMA_PMD_EXT_ROBUST_LBN  14
#define PMA_PMD_EXT_ROBUST_WIDTH 1
#define PMA_PMD_EXT_SSR_LBN     15
#define PMA_PMD_EXT_SSR_WIDTH   1

/* extended status register */
#define PMA_PMD_XSTATUS_REG     49153
#define PMA_PMD_XSTAT_MDIX_LBN  14
#define PMA_PMD_XSTAT_FLP_LBN   (12)

/* LED control register */
#define PMA_PMD_LED_CTRL_REG    49159
#define PMA_PMA_LED_ACTIVITY_LBN        (3)

/* LED function override register */
#define PMA_PMD_LED_OVERR_REG   49161
/* Bit positions for different LEDs (there are more but not wired on SFE4001)*/
#define PMA_PMD_LED_LINK_LBN    (0)
#define PMA_PMD_LED_SPEED_LBN   (2)
#define PMA_PMD_LED_TX_LBN      (4)
#define PMA_PMD_LED_RX_LBN      (6)
/* Override settings */
#define PMA_PMD_LED_AUTO        (0)     /* H/W control */
#define PMA_PMD_LED_ON          (1)
#define PMA_PMD_LED_OFF         (2)
#define PMA_PMD_LED_FLASH       (3)
#define PMA_PMD_LED_MASK        3
/* All LEDs under hardware control */
/* Green and Amber under hardware control, Red off */
#define SFX7101_PMA_PMD_LED_DEFAULT (PMA_PMD_LED_OFF << PMA_PMD_LED_RX_LBN)

#define PMA_PMD_SPEED_ENABLE_REG 49192
#define PMA_PMD_100TX_ADV_LBN    1
#define PMA_PMD_100TX_ADV_WIDTH  1
#define PMA_PMD_1000T_ADV_LBN    2
#define PMA_PMD_1000T_ADV_WIDTH  1
#define PMA_PMD_10000T_ADV_LBN   3
#define PMA_PMD_10000T_ADV_WIDTH 1
#define PMA_PMD_SPEED_LBN        4
#define PMA_PMD_SPEED_WIDTH      4

/* Misc register defines */
#define PCS_CLOCK_CTRL_REG      55297
#define PLL312_RST_N_LBN 2

#define PCS_SOFT_RST2_REG       55302
#define SERDES_RST_N_LBN 13
#define XGXS_RST_N_LBN 12

#define PCS_TEST_SELECT_REG     55303   /* PRM 10.5.8 */
#define CLK312_EN_LBN 3

/* PHYXS registers */
#define PHYXS_XCONTROL_REG      49152
#define PHYXS_RESET_LBN         15
#define PHYXS_RESET_WIDTH       1

#define PHYXS_TEST1         (49162)
#define LOOPBACK_NEAR_LBN   (8)
#define LOOPBACK_NEAR_WIDTH (1)

/* Boot status register */
#define PCS_BOOT_STATUS_REG             53248
#define PCS_BOOT_FATAL_ERROR_LBN        0
#define PCS_BOOT_PROGRESS_LBN           1
#define PCS_BOOT_PROGRESS_WIDTH         2
#define PCS_BOOT_PROGRESS_INIT          0
#define PCS_BOOT_PROGRESS_WAIT_MDIO     1
#define PCS_BOOT_PROGRESS_CHECKSUM      2
#define PCS_BOOT_PROGRESS_JUMP          3
#define PCS_BOOT_DOWNLOAD_WAIT_LBN      3
#define PCS_BOOT_CODE_STARTED_LBN       4

/* 100M/1G PHY registers */
#define GPHY_XCONTROL_REG       49152
#define GPHY_ISOLATE_LBN        10
#define GPHY_ISOLATE_WIDTH      1
#define GPHY_DUPLEX_LBN         8
#define GPHY_DUPLEX_WIDTH       1
#define GPHY_LOOPBACK_NEAR_LBN  14
#define GPHY_LOOPBACK_NEAR_WIDTH 1

#define C22EXT_STATUS_REG       49153
#define C22EXT_STATUS_LINK_LBN  2
#define C22EXT_STATUS_LINK_WIDTH 1

#define C22EXT_MSTSLV_CTRL                      49161
#define C22EXT_MSTSLV_CTRL_ADV_1000_HD_LBN      8
#define C22EXT_MSTSLV_CTRL_ADV_1000_FD_LBN      9

#define C22EXT_MSTSLV_STATUS                    49162
#define C22EXT_MSTSLV_STATUS_LP_1000_HD_LBN     10
#define C22EXT_MSTSLV_STATUS_LP_1000_FD_LBN     11

/* Time to wait between powering down the LNPGA and turning off the power
 * rails */
#define LNPGA_PDOWN_WAIT        (HZ / 5)

struct tenxpress_phy_data {
        enum efx_loopback_mode loopback_mode;
        enum efx_phy_mode phy_mode;
        int bad_lp_tries;
};

static int tenxpress_init(struct efx_nic *efx)
{
        /* Enable 312.5 MHz clock */
        efx_mdio_write(efx, MDIO_MMD_PCS, PCS_TEST_SELECT_REG,
                       1 << CLK312_EN_LBN);

        /* Set the LEDs up as: Green = Link, Amber = Link/Act, Red = Off */
        efx_mdio_set_flag(efx, MDIO_MMD_PMAPMD, PMA_PMD_LED_CTRL_REG,
                          1 << PMA_PMA_LED_ACTIVITY_LBN, true);
        efx_mdio_write(efx, MDIO_MMD_PMAPMD, PMA_PMD_LED_OVERR_REG,
                       SFX7101_PMA_PMD_LED_DEFAULT);

        return 0;
}

static int tenxpress_phy_probe(struct efx_nic *efx)
{
        struct tenxpress_phy_data *phy_data;

        /* Allocate phy private storage */
        phy_data = kzalloc(sizeof(*phy_data), GFP_KERNEL);
        if (!phy_data)
                return -ENOMEM;
        efx->phy_data = phy_data;
        phy_data->phy_mode = efx->phy_mode;

        efx->mdio.mmds = TENXPRESS_REQUIRED_DEVS;
        efx->mdio.mode_support = MDIO_SUPPORTS_C45;

        efx->loopback_modes = SFX7101_LOOPBACKS | FALCON_XMAC_LOOPBACKS;

        efx->link_advertising = (ADVERTISED_TP | ADVERTISED_Autoneg |
                                 ADVERTISED_10000baseT_Full);

        return 0;
}

static int tenxpress_phy_init(struct efx_nic *efx)
{
        int rc;

        falcon_board(efx)->type->init_phy(efx);

        if (!(efx->phy_mode & PHY_MODE_SPECIAL)) {
                rc = efx_mdio_wait_reset_mmds(efx, TENXPRESS_REQUIRED_DEVS);
                if (rc < 0)
                        return rc;

                rc = efx_mdio_check_mmds(efx, TENXPRESS_REQUIRED_DEVS);
                if (rc < 0)
                        return rc;
        }

        rc = tenxpress_init(efx);
        if (rc < 0)
                return rc;

        /* Reinitialise flow control settings */
        efx_link_set_wanted_fc(efx, efx->wanted_fc);
        efx_mdio_an_reconfigure(efx);

        schedule_timeout_uninterruptible(HZ / 5); /* 200ms */

        /* Let XGXS and SerDes out of reset */
        falcon_reset_xaui(efx);

        return 0;
}

/* Perform a "special software reset" on the PHY. The caller is
 * responsible for saving and restoring the PHY hardware registers
 * properly, and masking/unmasking LASI */
static int tenxpress_special_reset(struct efx_nic *efx)
{
        int rc, reg;

        /* The XGMAC clock is driven from the SFX7101 312MHz clock, so
         * a special software reset can glitch the XGMAC sufficiently for stats
         * requests to fail. */
        falcon_stop_nic_stats(efx);

        /* Initiate reset */
        reg = efx_mdio_read(efx, MDIO_MMD_PMAPMD, PMA_PMD_XCONTROL_REG);
        reg |= (1 << PMA_PMD_EXT_SSR_LBN);
        efx_mdio_write(efx, MDIO_MMD_PMAPMD, PMA_PMD_XCONTROL_REG, reg);

        mdelay(200);

        /* Wait for the blocks to come out of reset */
        rc = efx_mdio_wait_reset_mmds(efx, TENXPRESS_REQUIRED_DEVS);
        if (rc < 0)
                goto out;

        /* Try and reconfigure the device */
        rc = tenxpress_init(efx);
        if (rc < 0)
                goto out;

        /* Wait for the XGXS state machine to churn */
        mdelay(10);
out:
        falcon_start_nic_stats(efx);
        return rc;
}

static void sfx7101_check_bad_lp(struct efx_nic *efx, bool link_ok)
{
        struct tenxpress_phy_data *pd = efx->phy_data;
        bool bad_lp;
        int reg;

        if (link_ok) {
                bad_lp = false;
        } else {
                /* Check that AN has started but not completed. */
                reg = efx_mdio_read(efx, MDIO_MMD_AN, MDIO_STAT1);
                if (!(reg & MDIO_AN_STAT1_LPABLE))
                        return; /* LP status is unknown */
                bad_lp = !(reg & MDIO_AN_STAT1_COMPLETE);
                if (bad_lp)
                        pd->bad_lp_tries++;
        }

        /* Nothing to do if all is well and was previously so. */
        if (!pd->bad_lp_tries)
                return;

        /* Use the RX (red) LED as an error indicator once we've seen AN
         * failure several times in a row, and also log a message. */
        if (!bad_lp || pd->bad_lp_tries == MAX_BAD_LP_TRIES) {
                reg = efx_mdio_read(efx, MDIO_MMD_PMAPMD,
                                    PMA_PMD_LED_OVERR_REG);
                reg &= ~(PMA_PMD_LED_MASK << PMA_PMD_LED_RX_LBN);
                if (!bad_lp) {
                        reg |= PMA_PMD_LED_OFF << PMA_PMD_LED_RX_LBN;
                } else {
                        reg |= PMA_PMD_LED_FLASH << PMA_PMD_LED_RX_LBN;
                        netif_err(efx, link, efx->net_dev,
                                  "appears to be plugged into a port"
                                  " that is not 10GBASE-T capable. The PHY"
                                  " supports 10GBASE-T ONLY, so no link can"
                                  " be established\n");
                }
                efx_mdio_write(efx, MDIO_MMD_PMAPMD,
                               PMA_PMD_LED_OVERR_REG, reg);
                pd->bad_lp_tries = bad_lp;
        }
}

static bool sfx7101_link_ok(struct efx_nic *efx)
{
        return efx_mdio_links_ok(efx,
                                 MDIO_DEVS_PMAPMD |
                                 MDIO_DEVS_PCS |
                                 MDIO_DEVS_PHYXS);
}

static void tenxpress_ext_loopback(struct efx_nic *efx)
{
        efx_mdio_set_flag(efx, MDIO_MMD_PHYXS, PHYXS_TEST1,
                          1 << LOOPBACK_NEAR_LBN,
                          efx->loopback_mode == LOOPBACK_PHYXS);
}

static void tenxpress_low_power(struct efx_nic *efx)
{
        efx_mdio_set_mmds_lpower(
                efx, !!(efx->phy_mode & PHY_MODE_LOW_POWER),
                TENXPRESS_REQUIRED_DEVS);
}

static int tenxpress_phy_reconfigure(struct efx_nic *efx)
{
        struct tenxpress_phy_data *phy_data = efx->phy_data;
        bool phy_mode_change, loop_reset;

        if (efx->phy_mode & (PHY_MODE_OFF | PHY_MODE_SPECIAL)) {
                phy_data->phy_mode = efx->phy_mode;
                return 0;
        }

        phy_mode_change = (efx->phy_mode == PHY_MODE_NORMAL &&
                           phy_data->phy_mode != PHY_MODE_NORMAL);
        loop_reset = (LOOPBACK_OUT_OF(phy_data, efx, LOOPBACKS_EXTERNAL(efx)) ||
                      LOOPBACK_CHANGED(phy_data, efx, 1 << LOOPBACK_GPHY));

        if (loop_reset || phy_mode_change) {
                tenxpress_special_reset(efx);
                falcon_reset_xaui(efx);
        }

        tenxpress_low_power(efx);
        efx_mdio_transmit_disable(efx);
        efx_mdio_phy_reconfigure(efx);
        tenxpress_ext_loopback(efx);
        efx_mdio_an_reconfigure(efx);

        phy_data->loopback_mode = efx->loopback_mode;
        phy_data->phy_mode = efx->phy_mode;

        return 0;
}

static void
tenxpress_get_settings(struct efx_nic *efx, struct ethtool_cmd *ecmd);

/* Poll for link state changes */
static bool tenxpress_phy_poll(struct efx_nic *efx)
{
        struct efx_link_state old_state = efx->link_state;

        efx->link_state.up = sfx7101_link_ok(efx);
        efx->link_state.speed = 10000;
        efx->link_state.fd = true;
        efx->link_state.fc = efx_mdio_get_pause(efx);

        sfx7101_check_bad_lp(efx, efx->link_state.up);

        return !efx_link_state_equal(&efx->link_state, &old_state);
}

static void sfx7101_phy_fini(struct efx_nic *efx)
{
        int reg;

        /* Power down the LNPGA */
        reg = (1 << PMA_PMD_LNPGA_POWERDOWN_LBN);
        efx_mdio_write(efx, MDIO_MMD_PMAPMD, PMA_PMD_XCONTROL_REG, reg);

        /* Waiting here ensures that the board fini, which can turn
         * off the power to the PHY, won't get run until the LNPGA
         * powerdown has been given long enough to complete. */
        schedule_timeout_uninterruptible(LNPGA_PDOWN_WAIT); /* 200 ms */
}

static void tenxpress_phy_remove(struct efx_nic *efx)
{
        kfree(efx->phy_data);
        efx->phy_data = NULL;
}


/* Override the RX, TX and link LEDs */
void tenxpress_set_id_led(struct efx_nic *efx, enum efx_led_mode mode)
{
        int reg;

        switch (mode) {
        case EFX_LED_OFF:
                reg = (PMA_PMD_LED_OFF << PMA_PMD_LED_TX_LBN) |
                        (PMA_PMD_LED_OFF << PMA_PMD_LED_RX_LBN) |
                        (PMA_PMD_LED_OFF << PMA_PMD_LED_LINK_LBN);
                break;
        case EFX_LED_ON:
                reg = (PMA_PMD_LED_ON << PMA_PMD_LED_TX_LBN) |
                        (PMA_PMD_LED_ON << PMA_PMD_LED_RX_LBN) |
                        (PMA_PMD_LED_ON << PMA_PMD_LED_LINK_LBN);
                break;
        default:
                reg = SFX7101_PMA_PMD_LED_DEFAULT;
                break;
        }

        efx_mdio_write(efx, MDIO_MMD_PMAPMD, PMA_PMD_LED_OVERR_REG, reg);
}

static const char *const sfx7101_test_names[] = {
        "bist"
};

static const char *sfx7101_test_name(struct efx_nic *efx, unsigned int index)
{
        if (index < ARRAY_SIZE(sfx7101_test_names))
                return sfx7101_test_names[index];
        return NULL;
}

static int
sfx7101_run_tests(struct efx_nic *efx, int *results, unsigned flags)
{
        int rc;

        if (!(flags & ETH_TEST_FL_OFFLINE))
                return 0;

        /* BIST is automatically run after a special software reset */
        rc = tenxpress_special_reset(efx);
        results[0] = rc ? -1 : 1;

        efx_mdio_an_reconfigure(efx);

        return rc;
}

static void
tenxpress_get_settings(struct efx_nic *efx, struct ethtool_cmd *ecmd)
{
        u32 adv = 0, lpa = 0;
        int reg;

        reg = efx_mdio_read(efx, MDIO_MMD_AN, MDIO_AN_10GBT_CTRL);
        if (reg & MDIO_AN_10GBT_CTRL_ADV10G)
                adv |= ADVERTISED_10000baseT_Full;
        reg = efx_mdio_read(efx, MDIO_MMD_AN, MDIO_AN_10GBT_STAT);
        if (reg & MDIO_AN_10GBT_STAT_LP10G)
                lpa |= ADVERTISED_10000baseT_Full;

        mdio45_ethtool_gset_npage(&efx->mdio, ecmd, adv, lpa);

        /* In loopback, the PHY automatically brings up the correct interface,
         * but doesn't advertise the correct speed. So override it */
        if (LOOPBACK_EXTERNAL(efx))
                ethtool_cmd_speed_set(ecmd, SPEED_10000);
}

static int tenxpress_set_settings(struct efx_nic *efx, struct ethtool_cmd *ecmd)
{
        if (!ecmd->autoneg)
                return -EINVAL;

        return efx_mdio_set_settings(efx, ecmd);
}

static void sfx7101_set_npage_adv(struct efx_nic *efx, u32 advertising)
{
        efx_mdio_set_flag(efx, MDIO_MMD_AN, MDIO_AN_10GBT_CTRL,
                          MDIO_AN_10GBT_CTRL_ADV10G,
                          advertising & ADVERTISED_10000baseT_Full);
}

const struct efx_phy_operations falcon_sfx7101_phy_ops = {
        .probe            = tenxpress_phy_probe,
        .init             = tenxpress_phy_init,
        .reconfigure      = tenxpress_phy_reconfigure,
        .poll             = tenxpress_phy_poll,
        .fini             = sfx7101_phy_fini,
        .remove           = tenxpress_phy_remove,
        .get_settings     = tenxpress_get_settings,
        .set_settings     = tenxpress_set_settings,
        .set_npage_adv    = sfx7101_set_npage_adv,
        .test_alive       = efx_mdio_test_alive,
        .test_name        = sfx7101_test_name,
        .run_tests        = sfx7101_run_tests,
};