intelvf.c

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/*
 * Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 *
 * You can also choose to distribute this program under the terms of
 * the Unmodified Binary Distribution Licence (as given in the file
 * COPYING.UBDL), provided that you have satisfied its requirements.
 */

FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
FILE_SECBOOT ( PERMITTED );

#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <ipxe/io.h>
#include <ipxe/netdevice.h>
#include <ipxe/ethernet.h>
#include "intelvf.h"

/** @file
 *
 * Intel 10/100/1000 virtual function network card driver
 *
 */

/******************************************************************************
 *
 * Mailbox messages
 *
 ******************************************************************************
 */

/**
 * Write message to mailbox
 *
 * @v intel             Intel device
 * @v msg               Message
 */
static void intelvf_mbox_write ( struct intel_nic *intel,
                                 const union intelvf_msg *msg ) {
        const struct intelvf_msg_raw *raw = &msg->raw;
        unsigned int i;

        /* Write message */
        DBGC2 ( intel, "INTEL %p sending message", intel );
        for ( i = 0 ; i < ( sizeof ( *msg ) / sizeof ( raw->dword[0] ) ) ; i++){
                DBGC2 ( intel, "%c%08x", ( i ? ':' : ' ' ), raw->dword[i] );
                writel ( raw->dword[i], ( intel->regs + intel->mbox.mem +
                                          ( i * sizeof ( raw->dword[0] ) ) ) );
        }
        DBGC2 ( intel, "\n" );
}

/**
 * Read message from mailbox
 *
 * @v intel             Intel device
 * @v msg               Message
 */
static void intelvf_mbox_read ( struct intel_nic *intel,
                                union intelvf_msg *msg ) {
        struct intelvf_msg_raw *raw = &msg->raw;
        unsigned int i;

        /* Read message */
        DBGC2 ( intel, "INTEL %p received message", intel );
        for ( i = 0 ; i < ( sizeof ( *msg ) / sizeof ( raw->dword[0] ) ) ; i++){
                raw->dword[i] = readl ( intel->regs + intel->mbox.mem +
                                        ( i * sizeof ( raw->dword[0] ) ) );
                DBGC2 ( intel, "%c%08x", ( i ? ':' : ' ' ), raw->dword[i] );
        }
        DBGC2 ( intel, "\n" );
}

/**
 * Poll mailbox
 *
 * @v intel             Intel device
 * @ret rc              Return status code
 *
 * Note that polling the mailbox may fail if the underlying PF is
 * reset.
 */
int intelvf_mbox_poll ( struct intel_nic *intel ) {
        struct intel_mailbox *mbox = &intel->mbox;
        union intelvf_msg msg;
        uint32_t ctrl;

        /* Get mailbox status */
        ctrl = readl ( intel->regs + mbox->ctrl );

        /* Fail if a reset is in progress */
        if ( ctrl & INTELVF_MBCTRL_RSTI )
                return -EPIPE;

        /* Acknowledge (and ignore) any received messages */
        if ( ctrl & INTELVF_MBCTRL_PFSTS ) {
                intelvf_mbox_read ( intel, &msg );
                writel ( INTELVF_MBCTRL_ACK, intel->regs + mbox->ctrl );
        }

        return 0;
}

/**
 * Wait for PF reset to complete
 *
 * @v intel             Intel device
 * @ret rc              Return status code
 */
int intelvf_mbox_wait ( struct intel_nic *intel ) {
        unsigned int i;
        int rc;

        /* Wait until a poll completes successfully */
        for ( i = 0 ; i < INTELVF_MBOX_MAX_WAIT_MS ; i++ ) {

                /* Check for successful poll */
                if ( ( rc = intelvf_mbox_poll ( intel ) ) == 0 )
                        return 0;

                /* Delay */
                mdelay ( 1 );
        }

        DBGC ( intel, "INTEL %p timed out waiting for reset\n", intel );
        return -ETIMEDOUT;
}

/**
 * Send/receive mailbox message
 *
 * @v intel             Intel device
 * @v msg               Message buffer
 * @ret rc              Return status code
 */
int intelvf_mbox_msg ( struct intel_nic *intel, union intelvf_msg *msg ) {
        struct intel_mailbox *mbox = &intel->mbox;
        uint32_t ctrl;
        uint32_t seen = 0;
        unsigned int i;

        /* Sanity check */
        assert ( ! ( msg->hdr & INTELVF_MSG_RESPONSE ) );

        /* Handle mailbox */
        for ( i = 0 ; i < INTELVF_MBOX_MAX_WAIT_MS ; i++ ) {

                /* Attempt to claim mailbox, if we have not yet sent
                 * our message.
                 */
                if ( ! ( seen & INTELVF_MBCTRL_VFU ) )
                        writel ( INTELVF_MBCTRL_VFU, intel->regs + mbox->ctrl );

                /* Get mailbox status and record observed flags */
                ctrl = readl ( intel->regs + mbox->ctrl );
                seen |= ctrl;

                /* If a reset is in progress, clear VFU and abort */
                if ( ctrl & INTELVF_MBCTRL_RSTI ) {
                        writel ( 0, intel->regs + mbox->ctrl );
                        return -EPIPE;
                }

                /* Write message to mailbox, if applicable.  This
                 * potentially overwrites a message sent by the PF (if
                 * the PF has simultaneously released PFU (thus
                 * allowing our VFU) and asserted PFSTS), but that
                 * doesn't really matter since there are no
                 * unsolicited PF->VF messages that require the actual
                 * message content to be observed.
                 */
                if ( ctrl & INTELVF_MBCTRL_VFU )
                        intelvf_mbox_write ( intel, msg );

                /* Read message from mailbox, if applicable. */
                if ( ( seen & INTELVF_MBCTRL_VFU ) &&
                     ( seen & INTELVF_MBCTRL_PFACK ) &&
                     ( ctrl & INTELVF_MBCTRL_PFSTS ) )
                        intelvf_mbox_read ( intel, msg );

                /* Acknowledge received message (if applicable),
                 * release VFU lock, and send message (if applicable).
                 */
                ctrl = ( ( ( ctrl & INTELVF_MBCTRL_PFSTS ) ?
                           INTELVF_MBCTRL_ACK : 0 ) |
                         ( ( ctrl & INTELVF_MBCTRL_VFU ) ?
                           INTELVF_MBCTRL_REQ : 0 ) );
                writel ( ctrl, intel->regs + mbox->ctrl );

                /* Exit successfully if we have received a response */
                if ( msg->hdr & INTELVF_MSG_RESPONSE ) {

                        /* Sanity check */
                        assert ( seen & INTELVF_MBCTRL_VFU );
                        assert ( seen & INTELVF_MBCTRL_PFACK );
                        assert ( seen & INTELVF_MBCTRL_PFSTS );

                        return 0;
                }

                /* Delay */
                mdelay ( 1 );
        }

        DBGC ( intel, "INTEL %p timed out waiting for mailbox (seen %08x)\n",
               intel, seen );
        return -ETIMEDOUT;
}

/**
 * Send reset message and get initial MAC address
 *
 * @v intel             Intel device
 * @v hw_addr           Hardware address to fill in, or NULL
 * @ret rc              Return status code
 */
int intelvf_mbox_reset ( struct intel_nic *intel, uint8_t *hw_addr ) {
        union intelvf_msg msg;
        int rc;

        /* Send reset message */
        memset ( &msg, 0, sizeof ( msg ) );
        msg.hdr = INTELVF_MSG_TYPE_RESET;
        if ( ( rc = intelvf_mbox_msg ( intel, &msg ) ) != 0 ) {
                DBGC ( intel, "INTEL %p reset failed: %s\n",
                       intel, strerror ( rc ) );
                return rc;
        }

        /* Check response */
        if ( ( msg.hdr & INTELVF_MSG_TYPE_MASK ) != INTELVF_MSG_TYPE_RESET ) {
                DBGC ( intel, "INTEL %p reset unexpected response:\n", intel );
                DBGC_HDA ( intel, 0, &msg, sizeof ( msg ) );
                return -EPROTO;
        }

        /* Fill in MAC address, if applicable */
        if ( hw_addr ) {
                if ( msg.hdr & INTELVF_MSG_ACK ) {
                        memcpy ( hw_addr, msg.mac.mac, sizeof ( msg.mac.mac ) );
                        DBGC ( intel, "INTEL %p reset assigned MAC address "
                               "%s\n", intel, eth_ntoa ( hw_addr ) );
                } else {
                        eth_random_addr ( hw_addr );
                        DBGC ( intel, "INTEL %p reset generated MAC address "
                               "%s\n", intel, eth_ntoa ( hw_addr ) );
                }
        }

        return 0;
}

/**
 * Send set MAC address message
 *
 * @v intel             Intel device
 * @v ll_addr           Link-layer address
 * @ret rc              Return status code
 */
int intelvf_mbox_set_mac ( struct intel_nic *intel, const uint8_t *ll_addr ) {
        union intelvf_msg msg;
        int rc;

        /* Send set MAC address message */
        memset ( &msg, 0, sizeof ( msg ) );
        msg.hdr = INTELVF_MSG_TYPE_SET_MAC;
        memcpy ( msg.mac.mac, ll_addr, sizeof ( msg.mac.mac ) );
        if ( ( rc = intelvf_mbox_msg ( intel, &msg ) ) != 0 ) {
                DBGC ( intel, "INTEL %p set MAC address failed: %s\n",
                       intel, strerror ( rc ) );
                return rc;
        }

        /* Check response */
        if ( ( msg.hdr & INTELVF_MSG_TYPE_MASK ) != INTELVF_MSG_TYPE_SET_MAC ) {
                DBGC ( intel, "INTEL %p set MAC address unexpected response:\n",
                       intel );
                DBGC_HDA ( intel, 0, &msg, sizeof ( msg ) );
                return -EPROTO;
        }

        /* Check that we were allowed to set the MAC address */
        if ( ! ( msg.hdr & INTELVF_MSG_ACK ) ) {
                DBGC ( intel, "INTEL %p set MAC address refused\n", intel );
                return -EPERM;
        }

        return 0;
}

/**
 * Send set MTU message
 *
 * @v intel             Intel device
 * @v mtu               Maximum packet size
 * @ret rc              Return status code
 */
int intelvf_mbox_set_mtu ( struct intel_nic *intel, size_t mtu ) {
        union intelvf_msg msg;
        int rc;

        /* Send set MTU message */
        memset ( &msg, 0, sizeof ( msg ) );
        msg.hdr = INTELVF_MSG_TYPE_SET_MTU;
        msg.mtu.mtu = mtu;
        if ( ( rc = intelvf_mbox_msg ( intel, &msg ) ) != 0 ) {
                DBGC ( intel, "INTEL %p set MTU failed: %s\n",
                       intel, strerror ( rc ) );
                return rc;
        }

        /* Check response */
        if ( ( msg.hdr & INTELVF_MSG_TYPE_MASK ) != INTELVF_MSG_TYPE_SET_MTU ) {
                DBGC ( intel, "INTEL %p set MTU unexpected response:\n",
                       intel );
                DBGC_HDA ( intel, 0, &msg, sizeof ( msg ) );
                return -EPROTO;
        }

        /* Check that we were allowed to set the MTU */
        if ( ! ( msg.hdr & INTELVF_MSG_ACK ) ) {
                DBGC ( intel, "INTEL %p set MTU refused\n", intel );
                return -EPERM;
        }

        return 0;
}