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 <asm/io.h> 22 23 #include "emac.h" 24 #include "core.h" 25 26 int tah_attach(struct platform_device *ofdev, int channel) 27 { 28 struct tah_instance *dev = platform_get_drvdata(ofdev); 29 30 mutex_lock(&dev->lock); 31 /* Reset has been done at probe() time... nothing else to do for now */ 32 ++dev->users; 33 mutex_unlock(&dev->lock); 34 35 return 0; 36 } 37 38 void tah_detach(struct platform_device *ofdev, int channel) 39 { 40 struct tah_instance *dev = platform_get_drvdata(ofdev); 41 42 mutex_lock(&dev->lock); 43 --dev->users; 44 mutex_unlock(&dev->lock); 45 } 46 47 void tah_reset(struct platform_device *ofdev) 48 { 49 struct tah_instance *dev = platform_get_drvdata(ofdev); 50 struct tah_regs __iomem *p = dev->base; 51 int n; 52 53 /* Reset TAH */ 54 out_be32(&p->mr, TAH_MR_SR); 55 n = 100; 56 while ((in_be32(&p->mr) & TAH_MR_SR) && n) 57 --n; 58 59 if (unlikely(!n)) 60 printk(KERN_ERR "%s: reset timeout\n", 61 ofdev->dev.of_node->full_name); 62 63 /* 10KB TAH TX FIFO accommodates the max MTU of 9000 */ 64 out_be32(&p->mr, 65 TAH_MR_CVR | TAH_MR_ST_768 | TAH_MR_TFS_10KB | TAH_MR_DTFP | 66 TAH_MR_DIG); 67 } 68 69 int tah_get_regs_len(struct platform_device *ofdev) 70 { 71 return sizeof(struct emac_ethtool_regs_subhdr) + 72 sizeof(struct tah_regs); 73 } 74 75 void *tah_dump_regs(struct platform_device *ofdev, void *buf) 76 { 77 struct tah_instance *dev = platform_get_drvdata(ofdev); 78 struct emac_ethtool_regs_subhdr *hdr = buf; 79 struct tah_regs *regs = (struct tah_regs *)(hdr + 1); 80 81 hdr->version = 0; 82 hdr->index = 0; /* for now, are there chips with more than one 83 * zmii ? if yes, then we'll add a cell_index 84 * like we do for emac 85 */ 86 memcpy_fromio(regs, dev->base, sizeof(struct tah_regs)); 87 return regs + 1; 88 } 89 90 static int tah_probe(struct platform_device *ofdev) 91 { 92 struct device_node *np = ofdev->dev.of_node; 93 struct tah_instance *dev; 94 struct resource regs; 95 int rc; 96 97 rc = -ENOMEM; 98 dev = kzalloc(sizeof(struct tah_instance), GFP_KERNEL); 99 if (dev == NULL) 100 goto err_gone; 101 102 mutex_init(&dev->lock); 103 dev->ofdev = ofdev; 104 105 rc = -ENXIO; 106 if (of_address_to_resource(np, 0, ®s)) { 107 printk(KERN_ERR "%s: Can't get registers address\n", 108 np->full_name); 109 goto err_free; 110 } 111 112 rc = -ENOMEM; 113 dev->base = (struct tah_regs __iomem *)ioremap(regs.start, 114 sizeof(struct tah_regs)); 115 if (dev->base == NULL) { 116 printk(KERN_ERR "%s: Can't map device registers!\n", 117 np->full_name); 118 goto err_free; 119 } 120 121 platform_set_drvdata(ofdev, dev); 122 123 /* Initialize TAH and enable IPv4 checksum verification, no TSO yet */ 124 tah_reset(ofdev); 125 126 printk(KERN_INFO 127 "TAH %s initialized\n", ofdev->dev.of_node->full_name); 128 wmb(); 129 130 return 0; 131 132 err_free: 133 kfree(dev); 134 err_gone: 135 return rc; 136 } 137 138 static int tah_remove(struct platform_device *ofdev) 139 { 140 struct tah_instance *dev = platform_get_drvdata(ofdev); 141 142 WARN_ON(dev->users != 0); 143 144 iounmap(dev->base); 145 kfree(dev); 146 147 return 0; 148 } 149 150 static struct of_device_id tah_match[] = 151 { 152 { 153 .compatible = "ibm,tah", 154 }, 155 /* For backward compat with old DT */ 156 { 157 .type = "tah", 158 }, 159 {}, 160 }; 161 162 static struct platform_driver tah_driver = { 163 .driver = { 164 .name = "emac-tah", 165 .owner = THIS_MODULE, 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