1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * xtsonic.c
4  *
5  * (C) 2001 - 2007 Tensilica Inc.
6  *	Kevin Chea <kchea@yahoo.com>
7  *	Marc Gauthier <marc@linux-xtensa.org>
8  *	Chris Zankel <chris@zankel.net>
9  *
10  * (C) 1996,1998 by Thomas Bogendoerfer (tsbogend@alpha.franken.de)
11  *
12  * This driver is based on work from Andreas Busse, but most of
13  * the code is rewritten.
14  *
15  * (C) 1995 by Andreas Busse (andy@waldorf-gmbh.de)
16  *
17  * A driver for the onboard Sonic ethernet controller on the XT2000.
18  */
19 
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/types.h>
23 #include <linux/fcntl.h>
24 #include <linux/gfp.h>
25 #include <linux/interrupt.h>
26 #include <linux/init.h>
27 #include <linux/ioport.h>
28 #include <linux/in.h>
29 #include <linux/string.h>
30 #include <linux/delay.h>
31 #include <linux/errno.h>
32 #include <linux/netdevice.h>
33 #include <linux/etherdevice.h>
34 #include <linux/skbuff.h>
35 #include <linux/platform_device.h>
36 #include <linux/dma-mapping.h>
37 #include <linux/slab.h>
38 
39 #include <asm/io.h>
40 #include <asm/pgtable.h>
41 #include <asm/dma.h>
42 
43 static char xtsonic_string[] = "xtsonic";
44 
45 extern unsigned xtboard_nvram_valid(void);
46 extern void xtboard_get_ether_addr(unsigned char *buf);
47 
48 #include "sonic.h"
49 
50 /*
51  * According to the documentation for the Sonic ethernet controller,
52  * EOBC should be 760 words (1520 bytes) for 32-bit applications, and,
53  * as such, 2 words less than the buffer size. The value for RBSIZE
54  * defined in sonic.h, however is only 1520.
55  *
56  * (Note that in 16-bit configurations, EOBC is 759 words (1518 bytes) and
57  * RBSIZE 1520 bytes)
58  */
59 #undef SONIC_RBSIZE
60 #define SONIC_RBSIZE	1524
61 
62 /*
63  * The chip provides 256 byte register space.
64  */
65 #define SONIC_MEM_SIZE	0x100
66 
67 /*
68  * Macros to access SONIC registers
69  */
70 #define SONIC_READ(reg) \
71 	(0xffff & *((volatile unsigned int *)dev->base_addr+reg))
72 
73 #define SONIC_WRITE(reg,val) \
74 	*((volatile unsigned int *)dev->base_addr+reg) = val
75 
76 /*
77  * We cannot use station (ethernet) address prefixes to detect the
78  * sonic controller since these are board manufacturer depended.
79  * So we check for known Silicon Revision IDs instead.
80  */
81 static unsigned short known_revisions[] =
82 {
83 	0x101,			/* SONIC 83934 */
84 	0xffff			/* end of list */
85 };
86 
87 static int xtsonic_open(struct net_device *dev)
88 {
89 	int retval;
90 
91 	retval = request_irq(dev->irq, sonic_interrupt, 0, "sonic", dev);
92 	if (retval) {
93 		printk(KERN_ERR "%s: unable to get IRQ %d.\n",
94 		       dev->name, dev->irq);
95 		return -EAGAIN;
96 	}
97 
98 	retval = sonic_open(dev);
99 	if (retval)
100 		free_irq(dev->irq, dev);
101 	return retval;
102 }
103 
104 static int xtsonic_close(struct net_device *dev)
105 {
106 	int err;
107 	err = sonic_close(dev);
108 	free_irq(dev->irq, dev);
109 	return err;
110 }
111 
112 static const struct net_device_ops xtsonic_netdev_ops = {
113 	.ndo_open		= xtsonic_open,
114 	.ndo_stop		= xtsonic_close,
115 	.ndo_start_xmit		= sonic_send_packet,
116 	.ndo_get_stats		= sonic_get_stats,
117 	.ndo_set_rx_mode	= sonic_multicast_list,
118 	.ndo_tx_timeout		= sonic_tx_timeout,
119 	.ndo_validate_addr	= eth_validate_addr,
120 	.ndo_set_mac_address	= eth_mac_addr,
121 };
122 
123 static int __init sonic_probe1(struct net_device *dev)
124 {
125 	unsigned int silicon_revision;
126 	struct sonic_local *lp = netdev_priv(dev);
127 	unsigned int base_addr = dev->base_addr;
128 	int i;
129 	int err = 0;
130 
131 	if (!request_mem_region(base_addr, 0x100, xtsonic_string))
132 		return -EBUSY;
133 
134 	/*
135 	 * get the Silicon Revision ID. If this is one of the known
136 	 * one assume that we found a SONIC ethernet controller at
137 	 * the expected location.
138 	 */
139 	silicon_revision = SONIC_READ(SONIC_SR);
140 	i = 0;
141 	while ((known_revisions[i] != 0xffff) &&
142 			(known_revisions[i] != silicon_revision))
143 		i++;
144 
145 	if (known_revisions[i] == 0xffff) {
146 		pr_info("SONIC ethernet controller not found (0x%4x)\n",
147 			silicon_revision);
148 		return -ENODEV;
149 	}
150 
151 	/*
152 	 * Put the sonic into software reset, then retrieve ethernet address.
153 	 * Note: we are assuming that the boot-loader has initialized the cam.
154 	 */
155 	SONIC_WRITE(SONIC_CMD,SONIC_CR_RST);
156 	SONIC_WRITE(SONIC_DCR,
157 		    SONIC_DCR_WC0|SONIC_DCR_DW|SONIC_DCR_LBR|SONIC_DCR_SBUS);
158 	SONIC_WRITE(SONIC_CEP,0);
159 	SONIC_WRITE(SONIC_IMR,0);
160 
161 	SONIC_WRITE(SONIC_CMD,SONIC_CR_RST);
162 	SONIC_WRITE(SONIC_CEP,0);
163 
164 	for (i=0; i<3; i++) {
165 		unsigned int val = SONIC_READ(SONIC_CAP0-i);
166 		dev->dev_addr[i*2] = val;
167 		dev->dev_addr[i*2+1] = val >> 8;
168 	}
169 
170 	/* Initialize the device structure. */
171 
172 	lp->dma_bitmode = SONIC_BITMODE32;
173 
174 	/*
175 	 *  Allocate local private descriptor areas in uncached space.
176 	 *  The entire structure must be located within the same 64kb segment.
177 	 *  A simple way to ensure this is to allocate twice the
178 	 *  size of the structure -- given that the structure is
179 	 *  much less than 64 kB, at least one of the halves of
180 	 *  the allocated area will be contained entirely in 64 kB.
181 	 *  We also allocate extra space for a pointer to allow freeing
182 	 *  this structure later on (in xtsonic_cleanup_module()).
183 	 */
184 	lp->descriptors = dma_alloc_coherent(lp->device,
185 					     SIZEOF_SONIC_DESC *
186 					     SONIC_BUS_SCALE(lp->dma_bitmode),
187 					     &lp->descriptors_laddr,
188 					     GFP_KERNEL);
189 	if (lp->descriptors == NULL) {
190 		err = -ENOMEM;
191 		goto out;
192 	}
193 
194 	lp->cda = lp->descriptors;
195 	lp->tda = lp->cda + (SIZEOF_SONIC_CDA
196 			     * SONIC_BUS_SCALE(lp->dma_bitmode));
197 	lp->rda = lp->tda + (SIZEOF_SONIC_TD * SONIC_NUM_TDS
198 			     * SONIC_BUS_SCALE(lp->dma_bitmode));
199 	lp->rra = lp->rda + (SIZEOF_SONIC_RD * SONIC_NUM_RDS
200 			     * SONIC_BUS_SCALE(lp->dma_bitmode));
201 
202 	/* get the virtual dma address */
203 
204 	lp->cda_laddr = lp->descriptors_laddr;
205 	lp->tda_laddr = lp->cda_laddr + (SIZEOF_SONIC_CDA
206 				         * SONIC_BUS_SCALE(lp->dma_bitmode));
207 	lp->rda_laddr = lp->tda_laddr + (SIZEOF_SONIC_TD * SONIC_NUM_TDS
208 					 * SONIC_BUS_SCALE(lp->dma_bitmode));
209 	lp->rra_laddr = lp->rda_laddr + (SIZEOF_SONIC_RD * SONIC_NUM_RDS
210 					 * SONIC_BUS_SCALE(lp->dma_bitmode));
211 
212 	dev->netdev_ops		= &xtsonic_netdev_ops;
213 	dev->watchdog_timeo	= TX_TIMEOUT;
214 
215 	/*
216 	 * clear tally counter
217 	 */
218 	SONIC_WRITE(SONIC_CRCT,0xffff);
219 	SONIC_WRITE(SONIC_FAET,0xffff);
220 	SONIC_WRITE(SONIC_MPT,0xffff);
221 
222 	return 0;
223 out:
224 	release_region(dev->base_addr, SONIC_MEM_SIZE);
225 	return err;
226 }
227 
228 
229 /*
230  * Probe for a SONIC ethernet controller on an XT2000 board.
231  * Actually probing is superfluous but we're paranoid.
232  */
233 
234 int xtsonic_probe(struct platform_device *pdev)
235 {
236 	struct net_device *dev;
237 	struct sonic_local *lp;
238 	struct resource *resmem, *resirq;
239 	int err = 0;
240 
241 	if ((resmem = platform_get_resource(pdev, IORESOURCE_MEM, 0)) == NULL)
242 		return -ENODEV;
243 
244 	if ((resirq = platform_get_resource(pdev, IORESOURCE_IRQ, 0)) == NULL)
245 		return -ENODEV;
246 
247 	if ((dev = alloc_etherdev(sizeof(struct sonic_local))) == NULL)
248 		return -ENOMEM;
249 
250 	lp = netdev_priv(dev);
251 	lp->device = &pdev->dev;
252 	platform_set_drvdata(pdev, dev);
253 	SET_NETDEV_DEV(dev, &pdev->dev);
254 	netdev_boot_setup_check(dev);
255 
256 	dev->base_addr = resmem->start;
257 	dev->irq = resirq->start;
258 
259 	if ((err = sonic_probe1(dev)))
260 		goto out;
261 
262 	pr_info("SONIC ethernet @%08lx, MAC %pM, IRQ %d\n",
263 		dev->base_addr, dev->dev_addr, dev->irq);
264 
265 	sonic_msg_init(dev);
266 
267 	if ((err = register_netdev(dev)))
268 		goto out1;
269 
270 	return 0;
271 
272 out1:
273 	release_region(dev->base_addr, SONIC_MEM_SIZE);
274 out:
275 	free_netdev(dev);
276 
277 	return err;
278 }
279 
280 MODULE_DESCRIPTION("Xtensa XT2000 SONIC ethernet driver");
281 
282 #include "sonic.c"
283 
284 static int xtsonic_device_remove(struct platform_device *pdev)
285 {
286 	struct net_device *dev = platform_get_drvdata(pdev);
287 	struct sonic_local *lp = netdev_priv(dev);
288 
289 	unregister_netdev(dev);
290 	dma_free_coherent(lp->device,
291 			  SIZEOF_SONIC_DESC * SONIC_BUS_SCALE(lp->dma_bitmode),
292 			  lp->descriptors, lp->descriptors_laddr);
293 	release_region (dev->base_addr, SONIC_MEM_SIZE);
294 	free_netdev(dev);
295 
296 	return 0;
297 }
298 
299 static struct platform_driver xtsonic_driver = {
300 	.probe = xtsonic_probe,
301 	.remove = xtsonic_device_remove,
302 	.driver = {
303 		.name = xtsonic_string,
304 	},
305 };
306 
307 module_platform_driver(xtsonic_driver);
308