rgmii.c

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/*
 * drivers/net/ethernet/ibm/emac/rgmii.c
 *
 * Driver for PowerPC 4xx on-chip ethernet controller, RGMII bridge support.
 *
 * Copyright 2007 Benjamin Herrenschmidt, IBM Corp.
 *                <[email protected]>
 *
 * Based on the arch/ppc version of the driver:
 *
 * Copyright (c) 2004, 2005 Zultys Technologies.
 * Eugene Surovegin <[email protected]> or <[email protected]>
 *
 * Based on original work by
 *  Matt Porter <[email protected]>
 *  Copyright 2004 MontaVista Software, Inc.
 *
 * 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.
 *
 */
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/ethtool.h>
#include <asm/io.h>

#include "emac.h"
#include "debug.h"

// XXX FIXME: Axon seems to support a subset of the RGMII, we
// thus need to take that into account and possibly change some
// of the bit settings below that don't seem to quite match the
// AXON spec

/* RGMIIx_FER */
#define RGMII_FER_MASK(idx) (0x7 << ((idx) * 4))
#define RGMII_FER_RTBI(idx) (0x4 << ((idx) * 4))
#define RGMII_FER_RGMII(idx)    (0x5 << ((idx) * 4))
#define RGMII_FER_TBI(idx)  (0x6 << ((idx) * 4))
#define RGMII_FER_GMII(idx) (0x7 << ((idx) * 4))
#define RGMII_FER_MII(idx)  RGMII_FER_GMII(idx)

/* RGMIIx_SSR */
#define RGMII_SSR_MASK(idx) (0x7 << ((idx) * 8))
#define RGMII_SSR_100(idx)  (0x2 << ((idx) * 8))
#define RGMII_SSR_1000(idx) (0x4 << ((idx) * 8))

/* RGMII bridge supports only GMII/TBI and RGMII/RTBI PHYs */
static inline int rgmii_valid_mode(int phy_mode)
{
    return  phy_mode == PHY_MODE_GMII ||
        phy_mode == PHY_MODE_MII ||
        phy_mode == PHY_MODE_RGMII ||
        phy_mode == PHY_MODE_TBI ||
        phy_mode == PHY_MODE_RTBI;
}

static inline const char *rgmii_mode_name(int mode)
{
    switch (mode) {
    case PHY_MODE_RGMII:
        return "RGMII";
    case PHY_MODE_TBI:
        return "TBI";
    case PHY_MODE_GMII:
        return "GMII";
    case PHY_MODE_MII:
        return "MII";
    case PHY_MODE_RTBI:
        return "RTBI";
    default:
        BUG();
    }
}

static inline u32 rgmii_mode_mask(int mode, int input)
{
    switch (mode) {
    case PHY_MODE_RGMII:
        return RGMII_FER_RGMII(input);
    case PHY_MODE_TBI:
        return RGMII_FER_TBI(input);
    case PHY_MODE_GMII:
        return RGMII_FER_GMII(input);
    case PHY_MODE_MII:
        return RGMII_FER_MII(input);
    case PHY_MODE_RTBI:
        return RGMII_FER_RTBI(input);
    default:
        BUG();
    }
}

int __devinit rgmii_attach(struct platform_device *ofdev, int input, int mode)
{
    struct rgmii_instance *dev = dev_get_drvdata(&ofdev->dev);
    struct rgmii_regs __iomem *p = dev->base;

    RGMII_DBG(dev, "attach(%d)" NL, input);

    /* Check if we need to attach to a RGMII */
    if (input < 0 || !rgmii_valid_mode(mode)) {
        printk(KERN_ERR "%s: unsupported settings !\n",
               ofdev->dev.of_node->full_name);
        return -ENODEV;
    }

    mutex_lock(&dev->lock);

    /* Enable this input */
    out_be32(&p->fer, in_be32(&p->fer) | rgmii_mode_mask(mode, input));

    printk(KERN_NOTICE "%s: input %d in %s mode\n",
           ofdev->dev.of_node->full_name, input, rgmii_mode_name(mode));

    ++dev->users;

    mutex_unlock(&dev->lock);

    return 0;
}

void rgmii_set_speed(struct platform_device *ofdev, int input, int speed)
{
    struct rgmii_instance *dev = dev_get_drvdata(&ofdev->dev);
    struct rgmii_regs __iomem *p = dev->base;
    u32 ssr;

    mutex_lock(&dev->lock);

    ssr = in_be32(&p->ssr) & ~RGMII_SSR_MASK(input);

    RGMII_DBG(dev, "speed(%d, %d)" NL, input, speed);

    if (speed == SPEED_1000)
        ssr |= RGMII_SSR_1000(input);
    else if (speed == SPEED_100)
        ssr |= RGMII_SSR_100(input);

    out_be32(&p->ssr, ssr);

    mutex_unlock(&dev->lock);
}

void rgmii_get_mdio(struct platform_device *ofdev, int input)
{
    struct rgmii_instance *dev = dev_get_drvdata(&ofdev->dev);
    struct rgmii_regs __iomem *p = dev->base;
    u32 fer;

    RGMII_DBG2(dev, "get_mdio(%d)" NL, input);

    if (!(dev->flags & EMAC_RGMII_FLAG_HAS_MDIO))
        return;

    mutex_lock(&dev->lock);

    fer = in_be32(&p->fer);
    fer |= 0x00080000u >> input;
    out_be32(&p->fer, fer);
    (void)in_be32(&p->fer);

    DBG2(dev, " fer = 0x%08x\n", fer);
}

void rgmii_put_mdio(struct platform_device *ofdev, int input)
{
    struct rgmii_instance *dev = dev_get_drvdata(&ofdev->dev);
    struct rgmii_regs __iomem *p = dev->base;
    u32 fer;

    RGMII_DBG2(dev, "put_mdio(%d)" NL, input);

    if (!(dev->flags & EMAC_RGMII_FLAG_HAS_MDIO))
        return;

    fer = in_be32(&p->fer);
    fer &= ~(0x00080000u >> input);
    out_be32(&p->fer, fer);
    (void)in_be32(&p->fer);

    DBG2(dev, " fer = 0x%08x\n", fer);

    mutex_unlock(&dev->lock);
}

void rgmii_detach(struct platform_device *ofdev, int input)
{
    struct rgmii_instance *dev = dev_get_drvdata(&ofdev->dev);
    struct rgmii_regs __iomem *p;

    BUG_ON(!dev || dev->users == 0);
    p = dev->base;

    mutex_lock(&dev->lock);

    RGMII_DBG(dev, "detach(%d)" NL, input);

    /* Disable this input */
    out_be32(&p->fer, in_be32(&p->fer) & ~RGMII_FER_MASK(input));

    --dev->users;

    mutex_unlock(&dev->lock);
}

int rgmii_get_regs_len(struct platform_device *ofdev)
{
    return sizeof(struct emac_ethtool_regs_subhdr) +
        sizeof(struct rgmii_regs);
}

void *rgmii_dump_regs(struct platform_device *ofdev, void *buf)
{
    struct rgmii_instance *dev = dev_get_drvdata(&ofdev->dev);
    struct emac_ethtool_regs_subhdr *hdr = buf;
    struct rgmii_regs *regs = (struct rgmii_regs *)(hdr + 1);

    hdr->version = 0;
    hdr->index = 0; /* for now, are there chips with more than one
             * rgmii ? if yes, then we'll add a cell_index
             * like we do for emac
             */
    memcpy_fromio(regs, dev->base, sizeof(struct rgmii_regs));
    return regs + 1;
}


static int __devinit rgmii_probe(struct platform_device *ofdev)
{
    struct device_node *np = ofdev->dev.of_node;
    struct rgmii_instance *dev;
    struct resource regs;
    int rc;

    rc = -ENOMEM;
    dev = kzalloc(sizeof(struct rgmii_instance), GFP_KERNEL);
    if (dev == NULL)
        goto err_gone;

    mutex_init(&dev->lock);
    dev->ofdev = ofdev;

    rc = -ENXIO;
    if (of_address_to_resource(np, 0, &regs)) {
        printk(KERN_ERR "%s: Can't get registers address\n",
               np->full_name);
        goto err_free;
    }

    rc = -ENOMEM;
    dev->base = (struct rgmii_regs __iomem *)ioremap(regs.start,
                         sizeof(struct rgmii_regs));
    if (dev->base == NULL) {
        printk(KERN_ERR "%s: Can't map device registers!\n",
               np->full_name);
        goto err_free;
    }

    /* Check for RGMII flags */
    if (of_get_property(ofdev->dev.of_node, "has-mdio", NULL))
        dev->flags |= EMAC_RGMII_FLAG_HAS_MDIO;

    /* CAB lacks the right properties, fix this up */
    if (of_device_is_compatible(ofdev->dev.of_node, "ibm,rgmii-axon"))
        dev->flags |= EMAC_RGMII_FLAG_HAS_MDIO;

    DBG2(dev, " Boot FER = 0x%08x, SSR = 0x%08x\n",
         in_be32(&dev->base->fer), in_be32(&dev->base->ssr));

    /* Disable all inputs by default */
    out_be32(&dev->base->fer, 0);

    printk(KERN_INFO
           "RGMII %s initialized with%s MDIO support\n",
           ofdev->dev.of_node->full_name,
           (dev->flags & EMAC_RGMII_FLAG_HAS_MDIO) ? "" : "out");

    wmb();
    dev_set_drvdata(&ofdev->dev, dev);

    return 0;

 err_free:
    kfree(dev);
 err_gone:
    return rc;
}

static int __devexit rgmii_remove(struct platform_device *ofdev)
{
    struct rgmii_instance *dev = dev_get_drvdata(&ofdev->dev);

    dev_set_drvdata(&ofdev->dev, NULL);

    WARN_ON(dev->users != 0);

    iounmap(dev->base);
    kfree(dev);

    return 0;
}

static struct of_device_id rgmii_match[] =
{
    {
        .compatible = "ibm,rgmii",
    },
    {
        .type       = "emac-rgmii",
    },
    {},
};

static struct platform_driver rgmii_driver = {
    .driver = {
        .name = "emac-rgmii",
        .owner = THIS_MODULE,
        .of_match_table = rgmii_match,
    },
    .probe = rgmii_probe,
    .remove = rgmii_remove,
};

int __init rgmii_init(void)
{
    return platform_driver_register(&rgmii_driver);
}

void rgmii_exit(void)
{
    platform_driver_unregister(&rgmii_driver);
}