LXR linux/drivers/net/ethernet/ibm/emac/zmii.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * drivers/net/ethernet/ibm/emac/zmii.c
   4 *
   5 * Driver for PowerPC 4xx on-chip ethernet controller, ZMII bridge support.
   6 *
   7 * Copyright 2007 Benjamin Herrenschmidt, IBM Corp.
   8 *                <benh@kernel.crashing.org>
   9 *
  10 * Based on the arch/ppc version of the driver:
  11 *
  12 * Copyright (c) 2004, 2005 Zultys Technologies.
  13 * Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
  14 *
  15 * Based on original work by
  16 *      Armin Kuster <akuster@mvista.com>
  17 *      Copyright 2001 MontaVista Softare Inc.
  18 */
  19#include <linux/slab.h>
  20#include <linux/kernel.h>
  21#include <linux/ethtool.h>
  22#include <linux/of_address.h>
  23#include <asm/io.h>
  24
  25#include "emac.h"
  26#include "core.h"
  27
  28/* ZMIIx_FER */
  29#define ZMII_FER_MDI(idx)       (0x80000000 >> ((idx) * 4))
  30#define ZMII_FER_MDI_ALL        (ZMII_FER_MDI(0) | ZMII_FER_MDI(1) | \
  31                                 ZMII_FER_MDI(2) | ZMII_FER_MDI(3))
  32
  33#define ZMII_FER_SMII(idx)      (0x40000000 >> ((idx) * 4))
  34#define ZMII_FER_RMII(idx)      (0x20000000 >> ((idx) * 4))
  35#define ZMII_FER_MII(idx)       (0x10000000 >> ((idx) * 4))
  36
  37/* ZMIIx_SSR */
  38#define ZMII_SSR_SCI(idx)       (0x40000000 >> ((idx) * 4))
  39#define ZMII_SSR_FSS(idx)       (0x20000000 >> ((idx) * 4))
  40#define ZMII_SSR_SP(idx)        (0x10000000 >> ((idx) * 4))
  41
  42/* ZMII only supports MII, RMII and SMII
  43 * we also support autodetection for backward compatibility
  44 */
  45static inline int zmii_valid_mode(int mode)
  46{
  47        return  mode == PHY_INTERFACE_MODE_MII ||
  48                mode == PHY_INTERFACE_MODE_RMII ||
  49                mode == PHY_INTERFACE_MODE_SMII ||
  50                mode == PHY_INTERFACE_MODE_NA;
  51}
  52
  53static inline const char *zmii_mode_name(int mode)
  54{
  55        switch (mode) {
  56        case PHY_INTERFACE_MODE_MII:
  57                return "MII";
  58        case PHY_INTERFACE_MODE_RMII:
  59                return "RMII";
  60        case PHY_INTERFACE_MODE_SMII:
  61                return "SMII";
  62        default:
  63                BUG();
  64        }
  65}
  66
  67static inline u32 zmii_mode_mask(int mode, int input)
  68{
  69        switch (mode) {
  70        case PHY_INTERFACE_MODE_MII:
  71                return ZMII_FER_MII(input);
  72        case PHY_INTERFACE_MODE_RMII:
  73                return ZMII_FER_RMII(input);
  74        case PHY_INTERFACE_MODE_SMII:
  75                return ZMII_FER_SMII(input);
  76        default:
  77                return 0;
  78        }
  79}
  80
  81int zmii_attach(struct platform_device *ofdev, int input, int *mode)
  82{
  83        struct zmii_instance *dev = platform_get_drvdata(ofdev);
  84        struct zmii_regs __iomem *p = dev->base;
  85
  86        ZMII_DBG(dev, "init(%d, %d)" NL, input, *mode);
  87
  88        if (!zmii_valid_mode(*mode)) {
  89                /* Probably an EMAC connected to RGMII,
  90                 * but it still may need ZMII for MDIO so
  91                 * we don't fail here.
  92                 */
  93                dev->users++;
  94                return 0;
  95        }
  96
  97        mutex_lock(&dev->lock);
  98
  99        /* Autodetect ZMII mode if not specified.
 100         * This is only for backward compatibility with the old driver.
 101         * Please, always specify PHY mode in your board port to avoid
 102         * any surprises.
 103         */
 104        if (dev->mode == PHY_INTERFACE_MODE_NA) {
 105                if (*mode == PHY_INTERFACE_MODE_NA) {
 106                        u32 r = dev->fer_save;
 107
 108                        ZMII_DBG(dev, "autodetecting mode, FER = 0x%08x" NL, r);
 109
 110                        if (r & (ZMII_FER_MII(0) | ZMII_FER_MII(1)))
 111                                dev->mode = PHY_INTERFACE_MODE_MII;
 112                        else if (r & (ZMII_FER_RMII(0) | ZMII_FER_RMII(1)))
 113                                dev->mode = PHY_INTERFACE_MODE_RMII;
 114                        else
 115                                dev->mode = PHY_INTERFACE_MODE_SMII;
 116                } else {
 117                        dev->mode = *mode;
 118                }
 119                printk(KERN_NOTICE "%pOF: bridge in %s mode\n",
 120                       ofdev->dev.of_node,
 121                       zmii_mode_name(dev->mode));
 122        } else {
 123                /* All inputs must use the same mode */
 124                if (*mode != PHY_INTERFACE_MODE_NA && *mode != dev->mode) {
 125                        printk(KERN_ERR
 126                               "%pOF: invalid mode %d specified for input %d\n",
 127                               ofdev->dev.of_node, *mode, input);
 128                        mutex_unlock(&dev->lock);
 129                        return -EINVAL;
 130                }
 131        }
 132
 133        /* Report back correct PHY mode,
 134         * it may be used during PHY initialization.
 135         */
 136        *mode = dev->mode;
 137
 138        /* Enable this input */
 139        out_be32(&p->fer, in_be32(&p->fer) | zmii_mode_mask(dev->mode, input));
 140        ++dev->users;
 141
 142        mutex_unlock(&dev->lock);
 143
 144        return 0;
 145}
 146
 147void zmii_get_mdio(struct platform_device *ofdev, int input)
 148{
 149        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 150        u32 fer;
 151
 152        ZMII_DBG2(dev, "get_mdio(%d)" NL, input);
 153
 154        mutex_lock(&dev->lock);
 155
 156        fer = in_be32(&dev->base->fer) & ~ZMII_FER_MDI_ALL;
 157        out_be32(&dev->base->fer, fer | ZMII_FER_MDI(input));
 158}
 159
 160void zmii_put_mdio(struct platform_device *ofdev, int input)
 161{
 162        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 163
 164        ZMII_DBG2(dev, "put_mdio(%d)" NL, input);
 165        mutex_unlock(&dev->lock);
 166}
 167
 168
 169void zmii_set_speed(struct platform_device *ofdev, int input, int speed)
 170{
 171        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 172        u32 ssr;
 173
 174        mutex_lock(&dev->lock);
 175
 176        ssr = in_be32(&dev->base->ssr);
 177
 178        ZMII_DBG(dev, "speed(%d, %d)" NL, input, speed);
 179
 180        if (speed == SPEED_100)
 181                ssr |= ZMII_SSR_SP(input);
 182        else
 183                ssr &= ~ZMII_SSR_SP(input);
 184
 185        out_be32(&dev->base->ssr, ssr);
 186
 187        mutex_unlock(&dev->lock);
 188}
 189
 190void zmii_detach(struct platform_device *ofdev, int input)
 191{
 192        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 193
 194        BUG_ON(!dev || dev->users == 0);
 195
 196        mutex_lock(&dev->lock);
 197
 198        ZMII_DBG(dev, "detach(%d)" NL, input);
 199
 200        /* Disable this input */
 201        out_be32(&dev->base->fer,
 202                 in_be32(&dev->base->fer) & ~zmii_mode_mask(dev->mode, input));
 203
 204        --dev->users;
 205
 206        mutex_unlock(&dev->lock);
 207}
 208
 209int zmii_get_regs_len(struct platform_device *ofdev)
 210{
 211        return sizeof(struct emac_ethtool_regs_subhdr) +
 212                sizeof(struct zmii_regs);
 213}
 214
 215void *zmii_dump_regs(struct platform_device *ofdev, void *buf)
 216{
 217        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 218        struct emac_ethtool_regs_subhdr *hdr = buf;
 219        struct zmii_regs *regs = (struct zmii_regs *)(hdr + 1);
 220
 221        hdr->version = 0;
 222        hdr->index = 0; /* for now, are there chips with more than one
 223                         * zmii ? if yes, then we'll add a cell_index
 224                         * like we do for emac
 225                         */
 226        memcpy_fromio(regs, dev->base, sizeof(struct zmii_regs));
 227        return regs + 1;
 228}
 229
 230static int zmii_probe(struct platform_device *ofdev)
 231{
 232        struct device_node *np = ofdev->dev.of_node;
 233        struct zmii_instance *dev;
 234        struct resource regs;
 235        int rc;
 236
 237        rc = -ENOMEM;
 238        dev = kzalloc(sizeof(struct zmii_instance), GFP_KERNEL);
 239        if (dev == NULL)
 240                goto err_gone;
 241
 242        mutex_init(&dev->lock);
 243        dev->ofdev = ofdev;
 244        dev->mode = PHY_INTERFACE_MODE_NA;
 245
 246        rc = -ENXIO;
 247        if (of_address_to_resource(np, 0, &regs)) {
 248                printk(KERN_ERR "%pOF: Can't get registers address\n", np);
 249                goto err_free;
 250        }
 251
 252        rc = -ENOMEM;
 253        dev->base = (struct zmii_regs __iomem *)ioremap(regs.start,
 254                                                sizeof(struct zmii_regs));
 255        if (dev->base == NULL) {
 256                printk(KERN_ERR "%pOF: Can't map device registers!\n", np);
 257                goto err_free;
 258        }
 259
 260        /* We may need FER value for autodetection later */
 261        dev->fer_save = in_be32(&dev->base->fer);
 262
 263        /* Disable all inputs by default */
 264        out_be32(&dev->base->fer, 0);
 265
 266        printk(KERN_INFO "ZMII %pOF initialized\n", ofdev->dev.of_node);
 267        wmb();
 268        platform_set_drvdata(ofdev, dev);
 269
 270        return 0;
 271
 272 err_free:
 273        kfree(dev);
 274 err_gone:
 275        return rc;
 276}
 277
 278static int zmii_remove(struct platform_device *ofdev)
 279{
 280        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 281
 282        WARN_ON(dev->users != 0);
 283
 284        iounmap(dev->base);
 285        kfree(dev);
 286
 287        return 0;
 288}
 289
 290static const struct of_device_id zmii_match[] =
 291{
 292        {
 293                .compatible     = "ibm,zmii",
 294        },
 295        /* For backward compat with old DT */
 296        {
 297                .type           = "emac-zmii",
 298        },
 299        {},
 300};
 301
 302static struct platform_driver zmii_driver = {
 303        .driver = {
 304                .name = "emac-zmii",
 305                .of_match_table = zmii_match,
 306        },
 307        .probe = zmii_probe,
 308        .remove = zmii_remove,
 309};
 310
 311int __init zmii_init(void)
 312{
 313        return platform_driver_register(&zmii_driver);
 314}
 315
 316void zmii_exit(void)
 317{
 318        platform_driver_unregister(&zmii_driver);
 319}
 320