1 /*
2  * (C) Copyright 2007-2009 Michal Simek
3  * (C) Copyright 2003 Xilinx Inc.
4  *
5  * Michal SIMEK <monstr@monstr.eu>
6  *
7  * See file CREDITS for list of people who contributed to this
8  * project.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License as
12  * published by the Free Software Foundation; either version 2 of
13  * the License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
23  * MA 02111-1307 USA
24  */
25 
26 #include <common.h>
27 #include <net.h>
28 #include <config.h>
29 #include <malloc.h>
30 #include <asm/io.h>
31 
32 #undef DEBUG
33 
34 #define ENET_ADDR_LENGTH	6
35 
36 /* EmacLite constants */
37 #define XEL_BUFFER_OFFSET	0x0800	/* Next buffer's offset */
38 #define XEL_TPLR_OFFSET		0x07F4	/* Tx packet length */
39 #define XEL_TSR_OFFSET		0x07FC	/* Tx status */
40 #define XEL_RSR_OFFSET		0x17FC	/* Rx status */
41 #define XEL_RXBUFF_OFFSET	0x1000	/* Receive Buffer */
42 
43 /* Xmit complete */
44 #define XEL_TSR_XMIT_BUSY_MASK		0x00000001UL
45 /* Xmit interrupt enable bit */
46 #define XEL_TSR_XMIT_IE_MASK		0x00000008UL
47 /* Buffer is active, SW bit only */
48 #define XEL_TSR_XMIT_ACTIVE_MASK	0x80000000UL
49 /* Program the MAC address */
50 #define XEL_TSR_PROGRAM_MASK		0x00000002UL
51 /* define for programming the MAC address into the EMAC Lite */
52 #define XEL_TSR_PROG_MAC_ADDR	(XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_PROGRAM_MASK)
53 
54 /* Transmit packet length upper byte */
55 #define XEL_TPLR_LENGTH_MASK_HI		0x0000FF00UL
56 /* Transmit packet length lower byte */
57 #define XEL_TPLR_LENGTH_MASK_LO		0x000000FFUL
58 
59 /* Recv complete */
60 #define XEL_RSR_RECV_DONE_MASK		0x00000001UL
61 /* Recv interrupt enable bit */
62 #define XEL_RSR_RECV_IE_MASK		0x00000008UL
63 
64 struct xemaclite {
65 	u32 nexttxbuffertouse;	/* Next TX buffer to write to */
66 	u32 nextrxbuffertouse;	/* Next RX buffer to read from */
67 	u32 txpp;		/* TX ping pong buffer */
68 	u32 rxpp;		/* RX ping pong buffer */
69 };
70 
71 static u32 etherrxbuff[PKTSIZE_ALIGN/4]; /* Receive buffer */
72 
73 static void xemaclite_alignedread(u32 *srcptr, void *destptr, u32 bytecount)
74 {
75 	u32 i;
76 	u32 alignbuffer;
77 	u32 *to32ptr;
78 	u32 *from32ptr;
79 	u8 *to8ptr;
80 	u8 *from8ptr;
81 
82 	from32ptr = (u32 *) srcptr;
83 
84 	/* Word aligned buffer, no correction needed. */
85 	to32ptr = (u32 *) destptr;
86 	while (bytecount > 3) {
87 		*to32ptr++ = *from32ptr++;
88 		bytecount -= 4;
89 	}
90 	to8ptr = (u8 *) to32ptr;
91 
92 	alignbuffer = *from32ptr++;
93 	from8ptr = (u8 *) &alignbuffer;
94 
95 	for (i = 0; i < bytecount; i++)
96 		*to8ptr++ = *from8ptr++;
97 }
98 
99 static void xemaclite_alignedwrite(void *srcptr, u32 destptr, u32 bytecount)
100 {
101 	u32 i;
102 	u32 alignbuffer;
103 	u32 *to32ptr = (u32 *) destptr;
104 	u32 *from32ptr;
105 	u8 *to8ptr;
106 	u8 *from8ptr;
107 
108 	from32ptr = (u32 *) srcptr;
109 	while (bytecount > 3) {
110 
111 		*to32ptr++ = *from32ptr++;
112 		bytecount -= 4;
113 	}
114 
115 	alignbuffer = 0;
116 	to8ptr = (u8 *) &alignbuffer;
117 	from8ptr = (u8 *) from32ptr;
118 
119 	for (i = 0; i < bytecount; i++)
120 		*to8ptr++ = *from8ptr++;
121 
122 	*to32ptr++ = alignbuffer;
123 }
124 
125 static void emaclite_halt(struct eth_device *dev)
126 {
127 	debug("eth_halt\n");
128 }
129 
130 static int emaclite_init(struct eth_device *dev, bd_t *bis)
131 {
132 	struct xemaclite *emaclite = dev->priv;
133 	debug("EmacLite Initialization Started\n");
134 
135 /*
136  * TX - TX_PING & TX_PONG initialization
137  */
138 	/* Restart PING TX */
139 	out_be32 (dev->iobase + XEL_TSR_OFFSET, 0);
140 	/* Copy MAC address */
141 	xemaclite_alignedwrite(dev->enetaddr, dev->iobase, ENET_ADDR_LENGTH);
142 	/* Set the length */
143 	out_be32 (dev->iobase + XEL_TPLR_OFFSET, ENET_ADDR_LENGTH);
144 	/* Update the MAC address in the EMAC Lite */
145 	out_be32 (dev->iobase + XEL_TSR_OFFSET, XEL_TSR_PROG_MAC_ADDR);
146 	/* Wait for EMAC Lite to finish with the MAC address update */
147 	while ((in_be32 (dev->iobase + XEL_TSR_OFFSET) &
148 		XEL_TSR_PROG_MAC_ADDR) != 0)
149 		;
150 
151 	if (emaclite->txpp) {
152 		/* The same operation with PONG TX */
153 		out_be32 (dev->iobase + XEL_TSR_OFFSET + XEL_BUFFER_OFFSET, 0);
154 		xemaclite_alignedwrite(dev->enetaddr, dev->iobase +
155 			XEL_BUFFER_OFFSET, ENET_ADDR_LENGTH);
156 		out_be32 (dev->iobase + XEL_TPLR_OFFSET, ENET_ADDR_LENGTH);
157 		out_be32 (dev->iobase + XEL_TSR_OFFSET + XEL_BUFFER_OFFSET,
158 			XEL_TSR_PROG_MAC_ADDR);
159 		while ((in_be32 (dev->iobase + XEL_TSR_OFFSET +
160 			XEL_BUFFER_OFFSET) & XEL_TSR_PROG_MAC_ADDR) != 0)
161 			;
162 	}
163 
164 /*
165  * RX - RX_PING & RX_PONG initialization
166  */
167 	/* Write out the value to flush the RX buffer */
168 	out_be32 (dev->iobase + XEL_RSR_OFFSET, XEL_RSR_RECV_IE_MASK);
169 
170 	if (emaclite->rxpp)
171 		out_be32 (dev->iobase + XEL_RSR_OFFSET + XEL_BUFFER_OFFSET,
172 			XEL_RSR_RECV_IE_MASK);
173 
174 	debug("EmacLite Initialization complete\n");
175 	return 0;
176 }
177 
178 static int xemaclite_txbufferavailable(struct eth_device *dev)
179 {
180 	u32 reg;
181 	u32 txpingbusy;
182 	u32 txpongbusy;
183 	struct xemaclite *emaclite = dev->priv;
184 
185 	/*
186 	 * Read the other buffer register
187 	 * and determine if the other buffer is available
188 	 */
189 	reg = in_be32 (dev->iobase +
190 			emaclite->nexttxbuffertouse + 0);
191 	txpingbusy = ((reg & XEL_TSR_XMIT_BUSY_MASK) ==
192 			XEL_TSR_XMIT_BUSY_MASK);
193 
194 	reg = in_be32 (dev->iobase +
195 			(emaclite->nexttxbuffertouse ^ XEL_TSR_OFFSET) + 0);
196 	txpongbusy = ((reg & XEL_TSR_XMIT_BUSY_MASK) ==
197 			XEL_TSR_XMIT_BUSY_MASK);
198 
199 	return !(txpingbusy && txpongbusy);
200 }
201 
202 static int emaclite_send(struct eth_device *dev, void *ptr, int len)
203 {
204 	u32 reg;
205 	u32 baseaddress;
206 	struct xemaclite *emaclite = dev->priv;
207 
208 	u32 maxtry = 1000;
209 
210 	if (len > PKTSIZE)
211 		len = PKTSIZE;
212 
213 	while (!xemaclite_txbufferavailable(dev) && maxtry) {
214 		udelay(10);
215 		maxtry--;
216 	}
217 
218 	if (!maxtry) {
219 		printf("Error: Timeout waiting for ethernet TX buffer\n");
220 		/* Restart PING TX */
221 		out_be32 (dev->iobase + XEL_TSR_OFFSET, 0);
222 		if (emaclite->txpp) {
223 			out_be32 (dev->iobase + XEL_TSR_OFFSET +
224 				XEL_BUFFER_OFFSET, 0);
225 		}
226 		return -1;
227 	}
228 
229 	/* Determine the expected TX buffer address */
230 	baseaddress = (dev->iobase + emaclite->nexttxbuffertouse);
231 
232 	/* Determine if the expected buffer address is empty */
233 	reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
234 	if (((reg & XEL_TSR_XMIT_BUSY_MASK) == 0)
235 		&& ((in_be32 ((baseaddress) + XEL_TSR_OFFSET)
236 			& XEL_TSR_XMIT_ACTIVE_MASK) == 0)) {
237 
238 		if (emaclite->txpp)
239 			emaclite->nexttxbuffertouse ^= XEL_BUFFER_OFFSET;
240 
241 		debug("Send packet from 0x%x\n", baseaddress);
242 		/* Write the frame to the buffer */
243 		xemaclite_alignedwrite(ptr, baseaddress, len);
244 		out_be32 (baseaddress + XEL_TPLR_OFFSET,(len &
245 			(XEL_TPLR_LENGTH_MASK_HI | XEL_TPLR_LENGTH_MASK_LO)));
246 		reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
247 		reg |= XEL_TSR_XMIT_BUSY_MASK;
248 		if ((reg & XEL_TSR_XMIT_IE_MASK) != 0)
249 			reg |= XEL_TSR_XMIT_ACTIVE_MASK;
250 		out_be32 (baseaddress + XEL_TSR_OFFSET, reg);
251 		return 0;
252 	}
253 
254 	if (emaclite->txpp) {
255 		/* Switch to second buffer */
256 		baseaddress ^= XEL_BUFFER_OFFSET;
257 		/* Determine if the expected buffer address is empty */
258 		reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
259 		if (((reg & XEL_TSR_XMIT_BUSY_MASK) == 0)
260 			&& ((in_be32 ((baseaddress) + XEL_TSR_OFFSET)
261 				& XEL_TSR_XMIT_ACTIVE_MASK) == 0)) {
262 			debug("Send packet from 0x%x\n", baseaddress);
263 			/* Write the frame to the buffer */
264 			xemaclite_alignedwrite(ptr, baseaddress, len);
265 			out_be32 (baseaddress + XEL_TPLR_OFFSET, (len &
266 				(XEL_TPLR_LENGTH_MASK_HI |
267 					XEL_TPLR_LENGTH_MASK_LO)));
268 			reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
269 			reg |= XEL_TSR_XMIT_BUSY_MASK;
270 			if ((reg & XEL_TSR_XMIT_IE_MASK) != 0)
271 				reg |= XEL_TSR_XMIT_ACTIVE_MASK;
272 			out_be32 (baseaddress + XEL_TSR_OFFSET, reg);
273 			return 0;
274 		}
275 	}
276 
277 	puts("Error while sending frame\n");
278 	return -1;
279 }
280 
281 static int emaclite_recv(struct eth_device *dev)
282 {
283 	u32 length;
284 	u32 reg;
285 	u32 baseaddress;
286 	struct xemaclite *emaclite = dev->priv;
287 
288 	baseaddress = dev->iobase + emaclite->nextrxbuffertouse;
289 	reg = in_be32 (baseaddress + XEL_RSR_OFFSET);
290 	debug("Testing data at address 0x%x\n", baseaddress);
291 	if ((reg & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
292 		if (emaclite->rxpp)
293 			emaclite->nextrxbuffertouse ^= XEL_BUFFER_OFFSET;
294 	} else {
295 
296 		if (!emaclite->rxpp) {
297 			debug("No data was available - address 0x%x\n",
298 								baseaddress);
299 			return 0;
300 		} else {
301 			baseaddress ^= XEL_BUFFER_OFFSET;
302 			reg = in_be32 (baseaddress + XEL_RSR_OFFSET);
303 			if ((reg & XEL_RSR_RECV_DONE_MASK) !=
304 						XEL_RSR_RECV_DONE_MASK) {
305 				debug("No data was available - address 0x%x\n",
306 						baseaddress);
307 				return 0;
308 			}
309 		}
310 	}
311 	/* Get the length of the frame that arrived */
312 	switch(((ntohl(in_be32 (baseaddress + XEL_RXBUFF_OFFSET + 0xC))) &
313 			0xFFFF0000 ) >> 16) {
314 		case 0x806:
315 			length = 42 + 20; /* FIXME size of ARP */
316 			debug("ARP Packet\n");
317 			break;
318 		case 0x800:
319 			length = 14 + 14 +
320 			(((ntohl(in_be32 (baseaddress + XEL_RXBUFF_OFFSET +
321 						0x10))) & 0xFFFF0000) >> 16);
322 			/* FIXME size of IP packet */
323 			debug ("IP Packet\n");
324 			break;
325 		default:
326 			debug("Other Packet\n");
327 			length = PKTSIZE;
328 			break;
329 	}
330 
331 	xemaclite_alignedread((u32 *) (baseaddress + XEL_RXBUFF_OFFSET),
332 			etherrxbuff, length);
333 
334 	/* Acknowledge the frame */
335 	reg = in_be32 (baseaddress + XEL_RSR_OFFSET);
336 	reg &= ~XEL_RSR_RECV_DONE_MASK;
337 	out_be32 (baseaddress + XEL_RSR_OFFSET, reg);
338 
339 	debug("Packet receive from 0x%x, length %dB\n", baseaddress, length);
340 	NetReceive((uchar *) etherrxbuff, length);
341 	return length;
342 
343 }
344 
345 int xilinx_emaclite_initialize(bd_t *bis, unsigned long base_addr,
346 							int txpp, int rxpp)
347 {
348 	struct eth_device *dev;
349 	struct xemaclite *emaclite;
350 
351 	dev = calloc(1, sizeof(*dev));
352 	if (dev == NULL)
353 		return -1;
354 
355 	emaclite = calloc(1, sizeof(struct xemaclite));
356 	if (emaclite == NULL) {
357 		free(dev);
358 		return -1;
359 	}
360 
361 	dev->priv = emaclite;
362 
363 	emaclite->txpp = txpp;
364 	emaclite->rxpp = rxpp;
365 
366 	sprintf(dev->name, "Xelite.%lx", base_addr);
367 
368 	dev->iobase = base_addr;
369 	dev->init = emaclite_init;
370 	dev->halt = emaclite_halt;
371 	dev->send = emaclite_send;
372 	dev->recv = emaclite_recv;
373 
374 	eth_register(dev);
375 
376 	return 1;
377 }
378