1 /* 2 * drivers/net/ethernet/ibm/emac/tah.c 3 * 4 * Driver for PowerPC 4xx on-chip ethernet controller, TAH support. 5 * 6 * Copyright 2007 Benjamin Herrenschmidt, IBM Corp. 7 * <benh@kernel.crashing.org> 8 * 9 * Based on the arch/ppc version of the driver: 10 * 11 * Copyright 2004 MontaVista Software, Inc. 12 * Matt Porter <mporter@kernel.crashing.org> 13 * 14 * Copyright (c) 2005 Eugene Surovegin <ebs@ebshome.net> 15 * 16 * This program is free software; you can redistribute it and/or modify it 17 * under the terms of the GNU General Public License as published by the 18 * Free Software Foundation; either version 2 of the License, or (at your 19 * option) any later version. 20 */ 21 #include <linux/of_address.h> 22 #include <asm/io.h> 23 24 #include "emac.h" 25 #include "core.h" 26 27 int tah_attach(struct platform_device *ofdev, int channel) 28 { 29 struct tah_instance *dev = platform_get_drvdata(ofdev); 30 31 mutex_lock(&dev->lock); 32 /* Reset has been done at probe() time... nothing else to do for now */ 33 ++dev->users; 34 mutex_unlock(&dev->lock); 35 36 return 0; 37 } 38 39 void tah_detach(struct platform_device *ofdev, int channel) 40 { 41 struct tah_instance *dev = platform_get_drvdata(ofdev); 42 43 mutex_lock(&dev->lock); 44 --dev->users; 45 mutex_unlock(&dev->lock); 46 } 47 48 void tah_reset(struct platform_device *ofdev) 49 { 50 struct tah_instance *dev = platform_get_drvdata(ofdev); 51 struct tah_regs __iomem *p = dev->base; 52 int n; 53 54 /* Reset TAH */ 55 out_be32(&p->mr, TAH_MR_SR); 56 n = 100; 57 while ((in_be32(&p->mr) & TAH_MR_SR) && n) 58 --n; 59 60 if (unlikely(!n)) 61 printk(KERN_ERR "%s: reset timeout\n", 62 ofdev->dev.of_node->full_name); 63 64 /* 10KB TAH TX FIFO accommodates the max MTU of 9000 */ 65 out_be32(&p->mr, 66 TAH_MR_CVR | TAH_MR_ST_768 | TAH_MR_TFS_10KB | TAH_MR_DTFP | 67 TAH_MR_DIG); 68 } 69 70 int tah_get_regs_len(struct platform_device *ofdev) 71 { 72 return sizeof(struct emac_ethtool_regs_subhdr) + 73 sizeof(struct tah_regs); 74 } 75 76 void *tah_dump_regs(struct platform_device *ofdev, void *buf) 77 { 78 struct tah_instance *dev = platform_get_drvdata(ofdev); 79 struct emac_ethtool_regs_subhdr *hdr = buf; 80 struct tah_regs *regs = (struct tah_regs *)(hdr + 1); 81 82 hdr->version = 0; 83 hdr->index = 0; /* for now, are there chips with more than one 84 * zmii ? if yes, then we'll add a cell_index 85 * like we do for emac 86 */ 87 memcpy_fromio(regs, dev->base, sizeof(struct tah_regs)); 88 return regs + 1; 89 } 90 91 static int tah_probe(struct platform_device *ofdev) 92 { 93 struct device_node *np = ofdev->dev.of_node; 94 struct tah_instance *dev; 95 struct resource regs; 96 int rc; 97 98 rc = -ENOMEM; 99 dev = kzalloc(sizeof(struct tah_instance), GFP_KERNEL); 100 if (dev == NULL) 101 goto err_gone; 102 103 mutex_init(&dev->lock); 104 dev->ofdev = ofdev; 105 106 rc = -ENXIO; 107 if (of_address_to_resource(np, 0, ®s)) { 108 printk(KERN_ERR "%s: Can't get registers address\n", 109 np->full_name); 110 goto err_free; 111 } 112 113 rc = -ENOMEM; 114 dev->base = (struct tah_regs __iomem *)ioremap(regs.start, 115 sizeof(struct tah_regs)); 116 if (dev->base == NULL) { 117 printk(KERN_ERR "%s: Can't map device registers!\n", 118 np->full_name); 119 goto err_free; 120 } 121 122 platform_set_drvdata(ofdev, dev); 123 124 /* Initialize TAH and enable IPv4 checksum verification, no TSO yet */ 125 tah_reset(ofdev); 126 127 printk(KERN_INFO 128 "TAH %s initialized\n", ofdev->dev.of_node->full_name); 129 wmb(); 130 131 return 0; 132 133 err_free: 134 kfree(dev); 135 err_gone: 136 return rc; 137 } 138 139 static int tah_remove(struct platform_device *ofdev) 140 { 141 struct tah_instance *dev = platform_get_drvdata(ofdev); 142 143 WARN_ON(dev->users != 0); 144 145 iounmap(dev->base); 146 kfree(dev); 147 148 return 0; 149 } 150 151 static const struct of_device_id tah_match[] = 152 { 153 { 154 .compatible = "ibm,tah", 155 }, 156 /* For backward compat with old DT */ 157 { 158 .type = "tah", 159 }, 160 {}, 161 }; 162 163 static struct platform_driver tah_driver = { 164 .driver = { 165 .name = "emac-tah", 166 .of_match_table = tah_match, 167 }, 168 .probe = tah_probe, 169 .remove = tah_remove, 170 }; 171 172 int __init tah_init(void) 173 { 174 return platform_driver_register(&tah_driver); 175 } 176 177 void tah_exit(void) 178 { 179 platform_driver_unregister(&tah_driver); 180 } 181