xref: /openbmc/u-boot/drivers/net/cs8900.c (revision d66ff4ba)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Cirrus Logic CS8900A Ethernet
4  *
5  * (C) 2009 Ben Warren , biggerbadderben@gmail.com
6  *     Converted to use CONFIG_NET_MULTI API
7  *
8  * (C) 2003 Wolfgang Denk, wd@denx.de
9  *     Extension to synchronize ethaddr environment variable
10  *     against value in EEPROM
11  *
12  * (C) Copyright 2002
13  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
14  * Marius Groeger <mgroeger@sysgo.de>
15  *
16  * Copyright (C) 1999 Ben Williamson <benw@pobox.com>
17  *
18  * This program is loaded into SRAM in bootstrap mode, where it waits
19  * for commands on UART1 to read and write memory, jump to code etc.
20  * A design goal for this program is to be entirely independent of the
21  * target board.  Anything with a CL-PS7111 or EP7211 should be able to run
22  * this code in bootstrap mode.  All the board specifics can be handled on
23  * the host.
24  */
25 
26 #include <common.h>
27 #include <command.h>
28 #include <asm/io.h>
29 #include <net.h>
30 #include <malloc.h>
31 #include "cs8900.h"
32 
33 #undef DEBUG
34 
35 /* packet page register access functions */
36 
37 #ifdef CONFIG_CS8900_BUS32
38 
39 #define REG_WRITE(v, a) writel((v),(a))
40 #define REG_READ(a) readl((a))
41 
42 /* we don't need 16 bit initialisation on 32 bit bus */
43 #define get_reg_init_bus(r,d) get_reg((r),(d))
44 
45 #else
46 
47 #define REG_WRITE(v, a) writew((v),(a))
48 #define REG_READ(a) readw((a))
49 
50 static u16 get_reg_init_bus(struct eth_device *dev, int regno)
51 {
52 	/* force 16 bit busmode */
53 	struct cs8900_priv *priv = (struct cs8900_priv *)(dev->priv);
54 	uint8_t volatile * const iob = (uint8_t volatile * const)dev->iobase;
55 
56 	readb(iob);
57 	readb(iob + 1);
58 	readb(iob);
59 	readb(iob + 1);
60 	readb(iob);
61 
62 	REG_WRITE(regno, &priv->regs->pptr);
63 	return REG_READ(&priv->regs->pdata);
64 }
65 #endif
66 
67 static u16 get_reg(struct eth_device *dev, int regno)
68 {
69 	struct cs8900_priv *priv = (struct cs8900_priv *)(dev->priv);
70 	REG_WRITE(regno, &priv->regs->pptr);
71 	return REG_READ(&priv->regs->pdata);
72 }
73 
74 
75 static void put_reg(struct eth_device *dev, int regno, u16 val)
76 {
77 	struct cs8900_priv *priv = (struct cs8900_priv *)(dev->priv);
78 	REG_WRITE(regno, &priv->regs->pptr);
79 	REG_WRITE(val, &priv->regs->pdata);
80 }
81 
82 static void cs8900_reset(struct eth_device *dev)
83 {
84 	int tmo;
85 	u16 us;
86 
87 	/* reset NIC */
88 	put_reg(dev, PP_SelfCTL, get_reg(dev, PP_SelfCTL) | PP_SelfCTL_Reset);
89 
90 	/* wait for 200ms */
91 	udelay(200000);
92 	/* Wait until the chip is reset */
93 
94 	tmo = get_timer(0) + 1 * CONFIG_SYS_HZ;
95 	while ((((us = get_reg_init_bus(dev, PP_SelfSTAT)) &
96 		PP_SelfSTAT_InitD) == 0) && tmo < get_timer(0))
97 		/*NOP*/;
98 }
99 
100 static void cs8900_reginit(struct eth_device *dev)
101 {
102 	/* receive only error free packets addressed to this card */
103 	put_reg(dev, PP_RxCTL,
104 		PP_RxCTL_IA | PP_RxCTL_Broadcast | PP_RxCTL_RxOK);
105 	/* do not generate any interrupts on receive operations */
106 	put_reg(dev, PP_RxCFG, 0);
107 	/* do not generate any interrupts on transmit operations */
108 	put_reg(dev, PP_TxCFG, 0);
109 	/* do not generate any interrupts on buffer operations */
110 	put_reg(dev, PP_BufCFG, 0);
111 	/* enable transmitter/receiver mode */
112 	put_reg(dev, PP_LineCTL, PP_LineCTL_Rx | PP_LineCTL_Tx);
113 }
114 
115 void cs8900_get_enetaddr(struct eth_device *dev)
116 {
117 	int i;
118 
119 	/* verify chip id */
120 	if (get_reg_init_bus(dev, PP_ChipID) != 0x630e)
121 		return;
122 	cs8900_reset(dev);
123 	if ((get_reg(dev, PP_SelfSTAT) &
124 		(PP_SelfSTAT_EEPROM | PP_SelfSTAT_EEPROM_OK)) ==
125 		(PP_SelfSTAT_EEPROM | PP_SelfSTAT_EEPROM_OK)) {
126 
127 		/* Load the MAC from EEPROM */
128 		for (i = 0; i < 3; i++) {
129 			u32 Addr;
130 
131 			Addr = get_reg(dev, PP_IA + i * 2);
132 			dev->enetaddr[i * 2] = Addr & 0xFF;
133 			dev->enetaddr[i * 2 + 1] = Addr >> 8;
134 		}
135 	}
136 }
137 
138 void cs8900_halt(struct eth_device *dev)
139 {
140 	/* disable transmitter/receiver mode */
141 	put_reg(dev, PP_LineCTL, 0);
142 
143 	/* "shutdown" to show ChipID or kernel wouldn't find he cs8900 ... */
144 	get_reg_init_bus(dev, PP_ChipID);
145 }
146 
147 static int cs8900_init(struct eth_device *dev, bd_t * bd)
148 {
149 	uchar *enetaddr = dev->enetaddr;
150 	u16 id;
151 
152 	/* verify chip id */
153 	id = get_reg_init_bus(dev, PP_ChipID);
154 	if (id != 0x630e) {
155 		printf ("CS8900 Ethernet chip not found: "
156 			"ID=0x%04x instead 0x%04x\n", id, 0x630e);
157 		return 1;
158 	}
159 
160 	cs8900_reset (dev);
161 	/* set the ethernet address */
162 	put_reg(dev, PP_IA + 0, enetaddr[0] | (enetaddr[1] << 8));
163 	put_reg(dev, PP_IA + 2, enetaddr[2] | (enetaddr[3] << 8));
164 	put_reg(dev, PP_IA + 4, enetaddr[4] | (enetaddr[5] << 8));
165 
166 	cs8900_reginit(dev);
167 	return 0;
168 }
169 
170 /* Get a data block via Ethernet */
171 static int cs8900_recv(struct eth_device *dev)
172 {
173 	int i;
174 	u16 rxlen;
175 	u16 *addr;
176 	u16 status;
177 
178 	struct cs8900_priv *priv = (struct cs8900_priv *)(dev->priv);
179 
180 	status = get_reg(dev, PP_RER);
181 
182 	if ((status & PP_RER_RxOK) == 0)
183 		return 0;
184 
185 	status = REG_READ(&priv->regs->rtdata);
186 	rxlen = REG_READ(&priv->regs->rtdata);
187 
188 	if (rxlen > PKTSIZE_ALIGN + PKTALIGN)
189 		debug("packet too big!\n");
190 	for (addr = (u16 *)net_rx_packets[0], i = rxlen >> 1; i > 0; i--)
191 		*addr++ = REG_READ(&priv->regs->rtdata);
192 	if (rxlen & 1)
193 		*addr++ = REG_READ(&priv->regs->rtdata);
194 
195 	/* Pass the packet up to the protocol layers. */
196 	net_process_received_packet(net_rx_packets[0], rxlen);
197 	return rxlen;
198 }
199 
200 /* Send a data block via Ethernet. */
201 static int cs8900_send(struct eth_device *dev, void *packet, int length)
202 {
203 	volatile u16 *addr;
204 	int tmo;
205 	u16 s;
206 	struct cs8900_priv *priv = (struct cs8900_priv *)(dev->priv);
207 
208 retry:
209 	/* initiate a transmit sequence */
210 	REG_WRITE(PP_TxCmd_TxStart_Full, &priv->regs->txcmd);
211 	REG_WRITE(length, &priv->regs->txlen);
212 
213 	/* Test to see if the chip has allocated memory for the packet */
214 	if ((get_reg(dev, PP_BusSTAT) & PP_BusSTAT_TxRDY) == 0) {
215 		/* Oops... this should not happen! */
216 		debug("cs: unable to send packet; retrying...\n");
217 		for (tmo = get_timer(0) + 5 * CONFIG_SYS_HZ;
218 			get_timer(0) < tmo;)
219 			/*NOP*/;
220 		cs8900_reset(dev);
221 		cs8900_reginit(dev);
222 		goto retry;
223 	}
224 
225 	/* Write the contents of the packet */
226 	/* assume even number of bytes */
227 	for (addr = packet; length > 0; length -= 2)
228 		REG_WRITE(*addr++, &priv->regs->rtdata);
229 
230 	/* wait for transfer to succeed */
231 	tmo = get_timer(0) + 5 * CONFIG_SYS_HZ;
232 	while ((s = get_reg(dev, PP_TER) & ~0x1F) == 0) {
233 		if (get_timer(0) >= tmo)
234 			break;
235 	}
236 
237 	/* nothing */ ;
238 	if((s & (PP_TER_CRS | PP_TER_TxOK)) != PP_TER_TxOK) {
239 		debug("\ntransmission error %#x\n", s);
240 	}
241 
242 	return 0;
243 }
244 
245 static void cs8900_e2prom_ready(struct eth_device *dev)
246 {
247 	while (get_reg(dev, PP_SelfSTAT) & SI_BUSY)
248 		;
249 }
250 
251 /***********************************************************/
252 /* read a 16-bit word out of the EEPROM                    */
253 /***********************************************************/
254 
255 int cs8900_e2prom_read(struct eth_device *dev,
256 			u8 addr, u16 *value)
257 {
258 	cs8900_e2prom_ready(dev);
259 	put_reg(dev, PP_EECMD, EEPROM_READ_CMD | addr);
260 	cs8900_e2prom_ready(dev);
261 	*value = get_reg(dev, PP_EEData);
262 
263 	return 0;
264 }
265 
266 
267 /***********************************************************/
268 /* write a 16-bit word into the EEPROM                     */
269 /***********************************************************/
270 
271 int cs8900_e2prom_write(struct eth_device *dev, u8 addr, u16 value)
272 {
273 	cs8900_e2prom_ready(dev);
274 	put_reg(dev, PP_EECMD, EEPROM_WRITE_EN);
275 	cs8900_e2prom_ready(dev);
276 	put_reg(dev, PP_EEData, value);
277 	put_reg(dev, PP_EECMD, EEPROM_WRITE_CMD | addr);
278 	cs8900_e2prom_ready(dev);
279 	put_reg(dev, PP_EECMD, EEPROM_WRITE_DIS);
280 	cs8900_e2prom_ready(dev);
281 
282 	return 0;
283 }
284 
285 int cs8900_initialize(u8 dev_num, int base_addr)
286 {
287 	struct eth_device *dev;
288 	struct cs8900_priv *priv;
289 
290 	dev = malloc(sizeof(*dev));
291 	if (!dev) {
292 		return 0;
293 	}
294 	memset(dev, 0, sizeof(*dev));
295 
296 	priv = malloc(sizeof(*priv));
297 	if (!priv) {
298 		free(dev);
299 		return 0;
300 	}
301 	memset(priv, 0, sizeof(*priv));
302 	priv->regs = (struct cs8900_regs *)base_addr;
303 
304 	dev->iobase = base_addr;
305 	dev->priv = priv;
306 	dev->init = cs8900_init;
307 	dev->halt = cs8900_halt;
308 	dev->send = cs8900_send;
309 	dev->recv = cs8900_recv;
310 
311 	/* Load MAC address from EEPROM */
312 	cs8900_get_enetaddr(dev);
313 
314 	sprintf(dev->name, "%s-%hu", CS8900_DRIVERNAME, dev_num);
315 
316 	eth_register(dev);
317 	return 0;
318 }
319