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,
  82                phy_interface_t *mode)
  83{
  84        struct zmii_instance *dev = platform_get_drvdata(ofdev);
  85        struct zmii_regs __iomem *p = dev->base;
  86
  87        ZMII_DBG(dev, "init(%d, %d)" NL, input, *mode);
  88
  89        if (!zmii_valid_mode(*mode)) {
  90                /* Probably an EMAC connected to RGMII,
  91                 * but it still may need ZMII for MDIO so
  92                 * we don't fail here.
  93                 */
  94                dev->users++;
  95                return 0;
  96        }
  97
  98        mutex_lock(&dev->lock);
  99
 100        /* Autodetect ZMII mode if not specified.
 101         * This is only for backward compatibility with the old driver.
 102         * Please, always specify PHY mode in your board port to avoid
 103         * any surprises.
 104         */
 105        if (dev->mode == PHY_INTERFACE_MODE_NA) {
 106                if (*mode == PHY_INTERFACE_MODE_NA) {
 107                        u32 r = dev->fer_save;
 108
 109                        ZMII_DBG(dev, "autodetecting mode, FER = 0x%08x" NL, r);
 110
 111                        if (r & (ZMII_FER_MII(0) | ZMII_FER_MII(1)))
 112                                dev->mode = PHY_INTERFACE_MODE_MII;
 113                        else if (r & (ZMII_FER_RMII(0) | ZMII_FER_RMII(1)))
 114                                dev->mode = PHY_INTERFACE_MODE_RMII;
 115                        else
 116                                dev->mode = PHY_INTERFACE_MODE_SMII;
 117                } else {
 118                        dev->mode = *mode;
 119                }
 120                printk(KERN_NOTICE "%pOF: bridge in %s mode\n",
 121                       ofdev->dev.of_node,
 122                       zmii_mode_name(dev->mode));
 123        } else {
 124                /* All inputs must use the same mode */
 125                if (*mode != PHY_INTERFACE_MODE_NA && *mode != dev->mode) {
 126                        printk(KERN_ERR
 127                               "%pOF: invalid mode %d specified for input %d\n",
 128                               ofdev->dev.of_node, *mode, input);
 129                        mutex_unlock(&dev->lock);
 130                        return -EINVAL;
 131                }
 132        }
 133
 134        /* Report back correct PHY mode,
 135         * it may be used during PHY initialization.
 136         */
 137        *mode = dev->mode;
 138
 139        /* Enable this input */
 140        out_be32(&p->fer, in_be32(&p->fer) | zmii_mode_mask(dev->mode, input));
 141        ++dev->users;
 142
 143        mutex_unlock(&dev->lock);
 144
 145        return 0;
 146}
 147
 148void zmii_get_mdio(struct platform_device *ofdev, int input)
 149{
 150        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 151        u32 fer;
 152
 153        ZMII_DBG2(dev, "get_mdio(%d)" NL, input);
 154
 155        mutex_lock(&dev->lock);
 156
 157        fer = in_be32(&dev->base->fer) & ~ZMII_FER_MDI_ALL;
 158        out_be32(&dev->base->fer, fer | ZMII_FER_MDI(input));
 159}
 160
 161void zmii_put_mdio(struct platform_device *ofdev, int input)
 162{
 163        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 164
 165        ZMII_DBG2(dev, "put_mdio(%d)" NL, input);
 166        mutex_unlock(&dev->lock);
 167}
 168
 169
 170void zmii_set_speed(struct platform_device *ofdev, int input, int speed)
 171{
 172        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 173        u32 ssr;
 174
 175        mutex_lock(&dev->lock);
 176
 177        ssr = in_be32(&dev->base->ssr);
 178
 179        ZMII_DBG(dev, "speed(%d, %d)" NL, input, speed);
 180
 181        if (speed == SPEED_100)
 182                ssr |= ZMII_SSR_SP(input);
 183        else
 184                ssr &= ~ZMII_SSR_SP(input);
 185
 186        out_be32(&dev->base->ssr, ssr);
 187
 188        mutex_unlock(&dev->lock);
 189}
 190
 191void zmii_detach(struct platform_device *ofdev, int input)
 192{
 193        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 194
 195        BUG_ON(!dev || dev->users == 0);
 196
 197        mutex_lock(&dev->lock);
 198
 199        ZMII_DBG(dev, "detach(%d)" NL, input);
 200
 201        /* Disable this input */
 202        out_be32(&dev->base->fer,
 203                 in_be32(&dev->base->fer) & ~zmii_mode_mask(dev->mode, input));
 204
 205        --dev->users;
 206
 207        mutex_unlock(&dev->lock);
 208}
 209
 210int zmii_get_regs_len(struct platform_device *ofdev)
 211{
 212        return sizeof(struct emac_ethtool_regs_subhdr) +
 213                sizeof(struct zmii_regs);
 214}
 215
 216void *zmii_dump_regs(struct platform_device *ofdev, void *buf)
 217{
 218        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 219        struct emac_ethtool_regs_subhdr *hdr = buf;
 220        struct zmii_regs *regs = (struct zmii_regs *)(hdr + 1);
 221
 222        hdr->version = 0;
 223        hdr->index = 0; /* for now, are there chips with more than one
 224                         * zmii ? if yes, then we'll add a cell_index
 225                         * like we do for emac
 226                         */
 227        memcpy_fromio(regs, dev->base, sizeof(struct zmii_regs));
 228        return regs + 1;
 229}
 230
 231static int zmii_probe(struct platform_device *ofdev)
 232{
 233        struct device_node *np = ofdev->dev.of_node;
 234        struct zmii_instance *dev;
 235        struct resource regs;
 236        int rc;
 237
 238        rc = -ENOMEM;
 239        dev = kzalloc(sizeof(struct zmii_instance), GFP_KERNEL);
 240        if (dev == NULL)
 241                goto err_gone;
 242
 243        mutex_init(&dev->lock);
 244        dev->ofdev = ofdev;
 245        dev->mode = PHY_INTERFACE_MODE_NA;
 246
 247        rc = -ENXIO;
 248        if (of_address_to_resource(np, 0, &regs)) {
 249                printk(KERN_ERR "%pOF: Can't get registers address\n", np);
 250                goto err_free;
 251        }
 252
 253        rc = -ENOMEM;
 254        dev->base = (struct zmii_regs __iomem *)ioremap(regs.start,
 255                                                sizeof(struct zmii_regs));
 256        if (dev->base == NULL) {
 257                printk(KERN_ERR "%pOF: Can't map device registers!\n", np);
 258                goto err_free;
 259        }
 260
 261        /* We may need FER value for autodetection later */
 262        dev->fer_save = in_be32(&dev->base->fer);
 263
 264        /* Disable all inputs by default */
 265        out_be32(&dev->base->fer, 0);
 266
 267        printk(KERN_INFO "ZMII %pOF initialized\n", ofdev->dev.of_node);
 268        wmb();
 269        platform_set_drvdata(ofdev, dev);
 270
 271        return 0;
 272
 273 err_free:
 274        kfree(dev);
 275 err_gone:
 276        return rc;
 277}
 278
 279static int zmii_remove(struct platform_device *ofdev)
 280{
 281        struct zmii_instance *dev = platform_get_drvdata(ofdev);
 282
 283        WARN_ON(dev->users != 0);
 284
 285        iounmap(dev->base);
 286        kfree(dev);
 287
 288        return 0;
 289}
 290
 291static const struct of_device_id zmii_match[] =
 292{
 293        {
 294                .compatible     = "ibm,zmii",
 295        },
 296        /* For backward compat with old DT */
 297        {
 298                .type           = "emac-zmii",
 299        },
 300        {},
 301};
 302
 303static struct platform_driver zmii_driver = {
 304        .driver = {
 305                .name = "emac-zmii",
 306                .of_match_table = zmii_match,
 307        },
 308        .probe = zmii_probe,
 309        .remove = zmii_remove,
 310};
 311
 312int __init zmii_init(void)
 313{
 314        return platform_driver_register(&zmii_driver);
 315}
 316
 317void zmii_exit(void)
 318{
 319        platform_driver_unregister(&zmii_driver);
 320}
 321