Bug Summary

File:obj-scan-build/../linux/src/drivers/net/znet.c
Location:line 584, column 3
Description:Value stored to 'this_rfp_ptr' is never read

Annotated Source Code

1/* znet.c: An Zenith Z-Note ethernet driver for linux. */
2
3static const char *version = "znet.c:v1.02 9/23/94 becker@cesdis.gsfc.nasa.gov\n";
4
5/*
6 Written by Donald Becker.
7
8 The author may be reached as becker@cesdis.gsfc.nasa.gov.
9 This driver is based on the Linux skeleton driver. The copyright of the
10 skeleton driver is held by the United States Government, as represented
11 by DIRNSA, and it is released under the GPL.
12
13 Thanks to Mike Hollick for alpha testing and suggestions.
14
15 References:
16 The Crynwr packet driver.
17
18 "82593 CSMA/CD Core LAN Controller" Intel datasheet, 1992
19 Intel Microcommunications Databook, Vol. 1, 1990.
20 As usual with Intel, the documentation is incomplete and inaccurate.
21 I had to read the Crynwr packet driver to figure out how to actually
22 use the i82593, and guess at what register bits matched the loosely
23 related i82586.
24
25 Theory of Operation
26
27 The i82593 used in the Zenith Z-Note series operates using two(!) slave
28 DMA channels, one interrupt, and one 8-bit I/O port.
29
30 While there several ways to configure '593 DMA system, I chose the one
31 that seemed commensurate with the highest system performance in the face
32 of moderate interrupt latency: Both DMA channels are configured as
33 recirculating ring buffers, with one channel (#0) dedicated to Rx and
34 the other channel (#1) to Tx and configuration. (Note that this is
35 different than the Crynwr driver, where the Tx DMA channel is initialized
36 before each operation. That approach simplifies operation and Tx error
37 recovery, but requires additional I/O in normal operation and precludes
38 transmit buffer chaining.)
39
40 Both rings are set to 8192 bytes using {TX,RX}_RING_SIZE. This provides
41 a reasonable ring size for Rx, while simplifying DMA buffer allocation --
42 DMA buffers must not cross a 128K boundary. (In truth the size selection
43 was influenced by my lack of '593 documentation. I thus was constrained
44 to use the Crynwr '593 initialization table, which sets the Rx ring size
45 to 8K.)
46
47 Despite my usual low opinion about Intel-designed parts, I must admit
48 that the bulk data handling of the i82593 is a good design for
49 an integrated system, like a laptop, where using two slave DMA channels
50 doesn't pose a problem. I still take issue with using only a single I/O
51 port. In the same controlled environment there are essentially no
52 limitations on I/O space, and using multiple locations would eliminate
53 the need for multiple operations when looking at status registers,
54 setting the Rx ring boundary, or switching to promiscuous mode.
55
56 I also question Zenith's selection of the '593: one of the advertised
57 advantages of earlier Intel parts was that if you figured out the magic
58 initialization incantation you could use the same part on many different
59 network types. Zenith's use of the "FriendlyNet" (sic) connector rather
60 than an on-board transceiver leads me to believe that they were planning
61 to take advantage of this. But, uhmmm, the '593 omits all but ethernet
62 functionality from the serial subsystem.
63 */
64
65#include <linux/kernel.h>
66#include <linux/sched.h>
67#include <linux/string.h>
68#include <linux/ptrace.h>
69#include <linux/errno.h>
70#include <linux/interrupt.h>
71#include <linux/ioport.h>
72#include <asm/system.h>
73#include <asm/bitops.h>
74#include <asm/io.h>
75#include <asm/dma.h>
76
77#include <linux/netdevice.h>
78#include <linux/etherdevice.h>
79#include <linux/skbuff.h>
80#include <linux/if_arp.h>
81
82#ifndef ZNET_DEBUG1
83#define ZNET_DEBUG1 1
84#endif
85static unsigned int znet_debug = ZNET_DEBUG1;
86
87/* The DMA modes we need aren't in <dma.h>. */
88#define DMA_RX_MODE0x14 0x14 /* Auto init, I/O to mem, ++, demand. */
89#define DMA_TX_MODE0x18 0x18 /* Auto init, Mem to I/O, ++, demand. */
90#define dma_page_eq(ptr1, ptr2)((long)(ptr1)>>17 == (long)(ptr2)>>17) ((long)(ptr1)>>17 == (long)(ptr2)>>17)
91#define DMA_BUF_SIZE8192 8192
92#define RX_BUF_SIZE8192 8192
93#define TX_BUF_SIZE8192 8192
94
95/* Commands to the i82593 channel 0. */
96#define CMD0_CHNL_00x00 0x00
97#define CMD0_CHNL_10x10 0x10 /* Switch to channel 1. */
98#define CMD0_NOP(0x00) (CMD0_CHNL_00x00)
99#define CMD0_PORT_10x10 CMD0_CHNL_10x10
100#define CMD1_PORT_01 1
101#define CMD0_IA_SETUP1 1
102#define CMD0_CONFIGURE2 2
103#define CMD0_MULTICAST_LIST3 3
104#define CMD0_TRANSMIT4 4
105#define CMD0_DUMP6 6
106#define CMD0_DIAGNOSE7 7
107#define CMD0_Rx_ENABLE8 8
108#define CMD0_Rx_DISABLE10 10
109#define CMD0_Rx_STOP11 11
110#define CMD0_RETRANSMIT12 12
111#define CMD0_ABORT13 13
112#define CMD0_RESET14 14
113
114#define CMD0_ACK0x80 0x80
115
116#define CMD0_STAT0(0 << 5) (0 << 5)
117#define CMD0_STAT1(1 << 5) (1 << 5)
118#define CMD0_STAT2(2 << 5) (2 << 5)
119#define CMD0_STAT3(3 << 5) (3 << 5)
120
121#define net_localznet_private znet_private
122struct znet_private {
123 int rx_dma, tx_dma;
124 struct enet_statistics stats;
125 /* The starting, current, and end pointers for the packet buffers. */
126 ushort *rx_start, *rx_cur, *rx_end;
127 ushort *tx_start, *tx_cur, *tx_end;
128 ushort tx_buf_len; /* Tx buffer length, in words. */
129};
130
131/* Only one can be built-in;-> */
132static struct znet_private zn;
133static ushort dma_buffer1[DMA_BUF_SIZE8192/2];
134static ushort dma_buffer2[DMA_BUF_SIZE8192/2];
135static ushort dma_buffer3[DMA_BUF_SIZE8192/2 + 8];
136
137/* The configuration block. What an undocumented nightmare. The first
138 set of values are those suggested (without explanation) for ethernet
139 in the Intel 82586 databook. The rest appear to be completely undocumented,
140 except for cryptic notes in the Crynwr packet driver. This driver uses
141 the Crynwr values verbatim. */
142
143static unsigned char i593_init[] = {
144 0xAA, /* 0: 16-byte input & 80-byte output FIFO. */
145 /* threshold, 96-byte FIFO, 82593 mode. */
146 0x88, /* 1: Continuous w/interrupts, 128-clock DMA.*/
147 0x2E, /* 2: 8-byte preamble, NO address insertion, */
148 /* 6-byte Ethernet address, loopback off.*/
149 0x00, /* 3: Default priorities & backoff methods. */
150 0x60, /* 4: 96-bit interframe spacing. */
151 0x00, /* 5: 512-bit slot time (low-order). */
152 0xF2, /* 6: Slot time (high-order), 15 COLL retries. */
153 0x00, /* 7: Promisc-off, broadcast-on, default CRC. */
154 0x00, /* 8: Default carrier-sense, collision-detect. */
155 0x40, /* 9: 64-byte minimum frame length. */
156 0x5F, /* A: Type/length checks OFF, no CRC input,
157 "jabber" termination, etc. */
158 0x00, /* B: Full-duplex disabled. */
159 0x3F, /* C: Default multicast addresses & backoff. */
160 0x07, /* D: Default IFS retriggering. */
161 0x31, /* E: Internal retransmit, drop "runt" packets,
162 synchr. DRQ deassertion, 6 status bytes. */
163 0x22, /* F: Receive ring-buffer size (8K),
164 receive-stop register enable. */
165};
166
167struct netidblk {
168 char magic[8]; /* The magic number (string) "NETIDBLK" */
169 unsigned char netid[8]; /* The physical station address */
170 char nettype, globalopt;
171 char vendor[8]; /* The machine vendor and product name. */
172 char product[8];
173 char irq1, irq2; /* Interrupts, only one is currently used. */
174 char dma1, dma2;
175 short dma_mem_misc[8]; /* DMA buffer locations (unused in Linux). */
176 short iobase1, iosize1;
177 short iobase2, iosize2; /* Second iobase unused. */
178 char driver_options; /* Misc. bits */
179 char pad;
180};
181
182int znet_probe(struct devicelinux_device *dev);
183static int znet_open(struct devicelinux_device *dev);
184static int znet_send_packet(struct sk_buff *skb, struct devicelinux_device *dev);
185static void znet_interrupt(int irq, void *dev_id, struct pt_regs *regs);
186static void znet_rx(struct devicelinux_device *dev);
187static int znet_close(struct devicelinux_device *dev);
188static struct enet_statistics *net_get_stats(struct devicelinux_device *dev);
189static void set_multicast_list(struct devicelinux_device *dev);
190static void hardware_init(struct devicelinux_device *dev);
191static void update_stop_hit(short ioaddr, unsigned short rx_stop_offset);
192
193#ifdef notdef
194static struct sigaction znet_sigaction = { &znet_interrupt, 0, 0, NULL((void *) 0), };
195#endif
196
197
198/* The Z-Note probe is pretty easy. The NETIDBLK exists in the safe-to-probe
199 BIOS area. We just scan for the signature, and pull the vital parameters
200 out of the structure. */
201
202int znet_probe(struct devicelinux_device *dev)
203{
204 int i;
205 struct netidblk *netinfo;
206 char *p;
207
208 /* This code scans the region 0xf0000 to 0xfffff for a "NETIDBLK". */
209 for(p = (char *)0xf0000; p < (char *)0x100000; p++)
210 if (*p == 'N' && strncmp(p, "NETIDBLK", 8) == 0)
211 break;
212
213 if (p >= (char *)0x100000) {
214 if (znet_debug > 1)
215 printk(KERN_INFO"<6>" "No Z-Note ethernet adaptor found.\n");
216 return ENODEV19;
217 }
218 netinfo = (struct netidblk *)p;
219 dev->base_addr = netinfo->iobase1;
220 dev->irq = netinfo->irq1;
221
222 printk(KERN_INFO"<6>" "%s: ZNET at %#3lx,", dev->name, dev->base_addr);
223
224 /* The station address is in the "netidblk" at 0x0f0000. */
225 for (i = 0; i < 6; i++)
226 printk(" %2.2x", dev->dev_addr[i] = netinfo->netid[i]);
227
228 printk(", using IRQ %d DMA %d and %d.\n", dev->irq, netinfo->dma1,
229 netinfo->dma2);
230
231 if (znet_debug > 1) {
232 printk(KERN_INFO"<6>" "%s: vendor '%16.16s' IRQ1 %d IRQ2 %d DMA1 %d DMA2 %d.\n",
233 dev->name, netinfo->vendor,
234 netinfo->irq1, netinfo->irq2,
235 netinfo->dma1, netinfo->dma2);
236 printk(KERN_INFO"<6>" "%s: iobase1 %#x size %d iobase2 %#x size %d net type %2.2x.\n",
237 dev->name, netinfo->iobase1, netinfo->iosize1,
238 netinfo->iobase2, netinfo->iosize2, netinfo->nettype);
239 }
240
241 if (znet_debug > 0)
242 printk("%s%s", KERN_INFO"<6>", version);
243
244 dev->priv = (void *) &zn;
245 zn.rx_dma = netinfo->dma1;
246 zn.tx_dma = netinfo->dma2;
247
248 /* These should never fail. You can't add devices to a sealed box! */
249 if (request_irq(dev->irq, &znet_interrupt, 0, "ZNet", NULL((void *) 0))
250 || request_dma(zn.rx_dma,"ZNet rx")
251 || request_dma(zn.tx_dma,"ZNet tx")) {
252 printk(KERN_WARNING"<4>" "%s: Not opened -- resource busy?!?\n", dev->name);
253 return EBUSY16;
254 }
255 irq2dev_map[dev->irq] = dev;
256
257 /* Allocate buffer memory. We can cross a 128K boundary, so we
258 must be careful about the allocation. It's easiest to waste 8K. */
259 if (dma_page_eq(dma_buffer1, &dma_buffer1[RX_BUF_SIZE/2-1])((long)(dma_buffer1)>>17 == (long)(&dma_buffer1[8192
/2 -1])>>17))
260 zn.rx_start = dma_buffer1;
261 else
262 zn.rx_start = dma_buffer2;
263
264 if (dma_page_eq(dma_buffer3, &dma_buffer3[RX_BUF_SIZE/2-1])((long)(dma_buffer3)>>17 == (long)(&dma_buffer3[8192
/2 -1])>>17))
265 zn.tx_start = dma_buffer3;
266 else
267 zn.tx_start = dma_buffer2;
268 zn.rx_end = zn.rx_start + RX_BUF_SIZE8192/2;
269 zn.tx_buf_len = TX_BUF_SIZE8192/2;
270 zn.tx_end = zn.tx_start + zn.tx_buf_len;
271
272 /* The ZNET-specific entries in the device structure. */
273 dev->open = &znet_open;
274 dev->hard_start_xmit = &znet_send_packet;
275 dev->stop = &znet_close;
276 dev->get_stats = net_get_stats;
277 dev->set_multicast_list = &set_multicast_list;
278
279 /* Fill in the 'dev' with ethernet-generic values. */
280 ether_setup(dev);
281
282 return 0;
283}
284
285
286static int znet_open(struct devicelinux_device *dev)
287{
288 int ioaddr = dev->base_addr;
289
290 if (znet_debug > 2)
291 printk(KERN_DEBUG"<7>" "%s: znet_open() called.\n", dev->name);
292
293 /* Turn on the 82501 SIA, using zenith-specific magic. */
294 outb(0x10, 0xe6)((__builtin_constant_p((0xe6)) && (0xe6) < 256) ? __outbc
((0x10),(0xe6)) : __outb((0x10),(0xe6))); /* Select LAN control register */
295 outb(inb(0xe7) | 0x84, 0xe7)((__builtin_constant_p((0xe7)) && (0xe7) < 256) ? __outbc
((((__builtin_constant_p((0xe7)) && (0xe7) < 256) ?
__inbc(0xe7) : __inb(0xe7)) | 0x84),(0xe7)) : __outb((((__builtin_constant_p
((0xe7)) && (0xe7) < 256) ? __inbc(0xe7) : __inb(0xe7
)) | 0x84),(0xe7))); /* Turn on LAN power (bit 2). */
296 /* According to the Crynwr driver we should wait 50 msec. for the
297 LAN clock to stabilize. My experiments indicates that the '593 can
298 be initialized immediately. The delay is probably needed for the
299 DC-to-DC converter to come up to full voltage, and for the oscillator
300 to be spot-on at 20Mhz before transmitting.
301 Until this proves to be a problem we rely on the higher layers for the
302 delay and save allocating a timer entry. */
303
304 /* This follows the packet driver's lead, and checks for success. */
305 if (inb(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inbc(ioaddr) : __inb(ioaddr)) != 0x10 && inb(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inbc(ioaddr) : __inb(ioaddr)) != 0x00)
306 printk(KERN_WARNING"<4>" "%s: Problem turning on the transceiver power.\n",
307 dev->name);
308
309 dev->tbusy = 0;
310 dev->interrupt = 0;
311 hardware_init(dev);
312 dev->start = 1;
313
314 return 0;
315}
316
317static int znet_send_packet(struct sk_buff *skb, struct devicelinux_device *dev)
318{
319 int ioaddr = dev->base_addr;
320
321 if (znet_debug > 4)
322 printk(KERN_DEBUG"<7>" "%s: ZNet_send_packet(%ld).\n", dev->name, dev->tbusy);
323
324 /* Transmitter timeout, likely just recovery after suspending the machine. */
325 if (dev->tbusy) {
326 ushort event, tx_status, rx_offset, state;
327 int tickssofar = jiffies - dev->trans_start;
328 if (tickssofar < 10)
329 return 1;
330 outb(CMD0_STAT0, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((0 << 5)),(ioaddr)) : __outb(((0 << 5
)),(ioaddr))); event = inb(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inbc(ioaddr) : __inb(ioaddr));
331 outb(CMD0_STAT1, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((1 << 5)),(ioaddr)) : __outb(((1 << 5
)),(ioaddr))); tx_status = inw(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inwc(ioaddr) : __inw(ioaddr));
332 outb(CMD0_STAT2, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((2 << 5)),(ioaddr)) : __outb(((2 << 5
)),(ioaddr))); rx_offset = inw(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inwc(ioaddr) : __inw(ioaddr));
333 outb(CMD0_STAT3, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((3 << 5)),(ioaddr)) : __outb(((3 << 5
)),(ioaddr))); state = inb(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inbc(ioaddr) : __inb(ioaddr));
334 printk(KERN_WARNING"<4>" "%s: transmit timed out, status %02x %04x %04x %02x,"
335 " resetting.\n", dev->name, event, tx_status, rx_offset, state);
336 if (tx_status == 0x0400)
337 printk(KERN_WARNING"<4>" "%s: Tx carrier error, check transceiver cable.\n",
338 dev->name);
339 outb(CMD0_RESET, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((14),(ioaddr)) : __outb((14),(ioaddr)));
340 hardware_init(dev);
341 }
342
343 if (skb == NULL((void *) 0)) {
344 dev_tint(dev);
345 return 0;
346 }
347
348 /* Check that the part hasn't reset itself, probably from suspend. */
349 outb(CMD0_STAT0, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((0 << 5)),(ioaddr)) : __outb(((0 << 5
)),(ioaddr)));
350 if (inw(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inwc(ioaddr) : __inw(ioaddr)) == 0x0010
351 && inw(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inwc(ioaddr) : __inw(ioaddr)) == 0x0000
352 && inw(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inwc(ioaddr) : __inw(ioaddr)) == 0x0010)
353 hardware_init(dev);
354
355 /* Block a timer-based transmit from overlapping. This could better be
356 done with atomic_swap(1, dev->tbusy), but set_bit() works as well. */
357 if (set_bit(0, (void*)&dev->tbusy) != 0)
358 printk(KERN_WARNING"<4>" "%s: Transmitter access conflict.\n", dev->name);
359 else {
360 short length = ETH_ZLEN60 < skb->len ? skb->len : ETH_ZLEN60;
361 unsigned char *buf = (void *)skb->data;
362 ushort *tx_link = zn.tx_cur - 1;
363 ushort rnd_len = (length + 1)>>1;
364
365 {
366 short dma_port = ((zn.tx_dma&3)<<2) + IO_DMA2_BASE0xC0;
367 unsigned addr = inb(dma_port)((__builtin_constant_p((dma_port)) && (dma_port) <
256) ? __inbc(dma_port) : __inb(dma_port));
368 addr |= inb(dma_port)((__builtin_constant_p((dma_port)) && (dma_port) <
256) ? __inbc(dma_port) : __inb(dma_port)) << 8;
369 addr <<= 1;
370 if (((int)zn.tx_cur & 0x1ffff) != addr)
371 printk(KERN_WARNING"<4>" "Address mismatch at Tx: %#x vs %#x.\n",
372 (int)zn.tx_cur & 0xffff, addr);
373 zn.tx_cur = (ushort *)(((int)zn.tx_cur & 0xfe0000) | addr);
374 }
375
376 if (zn.tx_cur >= zn.tx_end)
377 zn.tx_cur = zn.tx_start;
378 *zn.tx_cur++ = length;
379 if (zn.tx_cur + rnd_len + 1 > zn.tx_end) {
380 int semi_cnt = (zn.tx_end - zn.tx_cur)<<1; /* Cvrt to byte cnt. */
381 memcpy(zn.tx_cur, buf, semi_cnt)(__builtin_constant_p(semi_cnt) ? __constant_memcpy((zn.tx_cur
),(buf),(semi_cnt)) : __memcpy((zn.tx_cur),(buf),(semi_cnt)));
382 rnd_len -= semi_cnt>>1;
383 memcpy(zn.tx_start, buf + semi_cnt, length - semi_cnt)(__builtin_constant_p(length - semi_cnt) ? __constant_memcpy(
(zn.tx_start),(buf + semi_cnt),(length - semi_cnt)) : __memcpy
((zn.tx_start),(buf + semi_cnt),(length - semi_cnt)));
384 zn.tx_cur = zn.tx_start + rnd_len;
385 } else {
386 memcpy(zn.tx_cur, buf, skb->len)(__builtin_constant_p(skb->len) ? __constant_memcpy((zn.tx_cur
),(buf),(skb->len)) : __memcpy((zn.tx_cur),(buf),(skb->
len)));
387 zn.tx_cur += rnd_len;
388 }
389 *zn.tx_cur++ = 0;
390 cli()__asm__ __volatile__ ("cli": : :"memory"); {
391 *tx_link = CMD0_TRANSMIT4 + CMD0_CHNL_10x10;
392 /* Is this always safe to do? */
393 outb(CMD0_TRANSMIT + CMD0_CHNL_1,ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((4 + 0x10),(ioaddr)) : __outb((4 + 0x10),(ioaddr)
));
394 } sti()__asm__ __volatile__ ("sti": : :"memory");
395
396 dev->trans_start = jiffies;
397 if (znet_debug > 4)
398 printk(KERN_DEBUG"<7>" "%s: Transmitter queued, length %d.\n", dev->name, length);
399 }
400 dev_kfree_skb(skb, FREE_WRITE0);
401 return 0;
402}
403
404/* The ZNET interrupt handler. */
405static void znet_interrupt(int irq, void *dev_id, struct pt_regs * regs)
406{
407 struct devicelinux_device *dev = irq2dev_map[irq];
408 int ioaddr;
409 int boguscnt = 20;
410
411 if (dev == NULL((void *) 0)) {
412 printk(KERN_WARNING"<4>" "znet_interrupt(): IRQ %d for unknown device.\n", irq);
413 return;
414 }
415
416 dev->interrupt = 1;
417 ioaddr = dev->base_addr;
418
419 outb(CMD0_STAT0, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((0 << 5)),(ioaddr)) : __outb(((0 << 5
)),(ioaddr)));
420 do {
421 ushort status = inb(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inbc(ioaddr) : __inb(ioaddr));
422 if (znet_debug > 5) {
423 ushort result, rx_ptr, running;
424 outb(CMD0_STAT1, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((1 << 5)),(ioaddr)) : __outb(((1 << 5
)),(ioaddr)));
425 result = inw(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inwc(ioaddr) : __inw(ioaddr));
426 outb(CMD0_STAT2, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((2 << 5)),(ioaddr)) : __outb(((2 << 5
)),(ioaddr)));
427 rx_ptr = inw(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inwc(ioaddr) : __inw(ioaddr));
428 outb(CMD0_STAT3, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((3 << 5)),(ioaddr)) : __outb(((3 << 5
)),(ioaddr)));
429 running = inb(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inbc(ioaddr) : __inb(ioaddr));
430 printk(KERN_DEBUG"<7>" "%s: interrupt, status %02x, %04x %04x %02x serial %d.\n",
431 dev->name, status, result, rx_ptr, running, boguscnt);
432 }
433 if ((status & 0x80) == 0)
434 break;
435
436 if ((status & 0x0F) == 4) { /* Transmit done. */
437 struct net_localznet_private *lp = (struct net_localznet_private *)dev->priv;
438 int tx_status;
439 outb(CMD0_STAT1, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((1 << 5)),(ioaddr)) : __outb(((1 << 5
)),(ioaddr)));
440 tx_status = inw(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inwc(ioaddr) : __inw(ioaddr));
441 /* It's undocumented, but tx_status seems to match the i82586. */
442 if (tx_status & 0x2000) {
443 lp->stats.tx_packets++;
444 lp->stats.collisions += tx_status & 0xf;
445 } else {
446 if (tx_status & 0x0600) lp->stats.tx_carrier_errors++;
447 if (tx_status & 0x0100) lp->stats.tx_fifo_errors++;
448 if (!(tx_status & 0x0040)) lp->stats.tx_heartbeat_errors++;
449 if (tx_status & 0x0020) lp->stats.tx_aborted_errors++;
450 /* ...and the catch-all. */
451 if ((tx_status | 0x0760) != 0x0760)
452 lp->stats.tx_errors++;
453 }
454 dev->tbusy = 0;
455 mark_bh(NET_BH); /* Inform upper layers. */
456 }
457
458 if ((status & 0x40)
459 || (status & 0x0f) == 11) {
460 znet_rx(dev);
461 }
462 /* Clear the interrupts we've handled. */
463 outb(CMD0_ACK,ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((0x80),(ioaddr)) : __outb((0x80),(ioaddr)));
464 } while (boguscnt--);
465
466 dev->interrupt = 0;
467 return;
468}
469
470static void znet_rx(struct devicelinux_device *dev)
471{
472 struct net_localznet_private *lp = (struct net_localznet_private *)dev->priv;
473 int ioaddr = dev->base_addr;
474 int boguscount = 1;
475 short next_frame_end_offset = 0; /* Offset of next frame start. */
476 short *cur_frame_end;
477 short cur_frame_end_offset;
478
479 outb(CMD0_STAT2, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((2 << 5)),(ioaddr)) : __outb(((2 << 5
)),(ioaddr)));
480 cur_frame_end_offset = inw(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inwc(ioaddr) : __inw(ioaddr));
481
482 if (cur_frame_end_offset == zn.rx_cur - zn.rx_start) {
483 printk(KERN_WARNING"<4>" "%s: Interrupted, but nothing to receive, offset %03x.\n",
484 dev->name, cur_frame_end_offset);
485 return;
486 }
487
488 /* Use same method as the Crynwr driver: construct a forward list in
489 the same area of the backwards links we now have. This allows us to
490 pass packets to the upper layers in the order they were received --
491 important for fast-path sequential operations. */
492 while (zn.rx_start + cur_frame_end_offset != zn.rx_cur
493 && ++boguscount < 5) {
494 unsigned short hi_cnt, lo_cnt, hi_status, lo_status;
495 int count, status;
496
497 if (cur_frame_end_offset < 4) {
498 /* Oh no, we have a special case: the frame trailer wraps around
499 the end of the ring buffer. We've saved space at the end of
500 the ring buffer for just this problem. */
501 memcpy(zn.rx_end, zn.rx_start, 8)(__builtin_constant_p(8) ? __constant_memcpy((zn.rx_end),(zn.
rx_start),(8)) : __memcpy((zn.rx_end),(zn.rx_start),(8)));
502 cur_frame_end_offset += (RX_BUF_SIZE8192/2);
503 }
504 cur_frame_end = zn.rx_start + cur_frame_end_offset - 4;
505
506 lo_status = *cur_frame_end++;
507 hi_status = *cur_frame_end++;
508 status = ((hi_status & 0xff) << 8) + (lo_status & 0xff);
509 lo_cnt = *cur_frame_end++;
510 hi_cnt = *cur_frame_end++;
511 count = ((hi_cnt & 0xff) << 8) + (lo_cnt & 0xff);
512
513 if (znet_debug > 5)
514 printk(KERN_DEBUG"<7>" "Constructing trailer at location %03x, %04x %04x %04x %04x"
515 " count %#x status %04x.\n",
516 cur_frame_end_offset<<1, lo_status, hi_status, lo_cnt, hi_cnt,
517 count, status);
518 cur_frame_end[-4] = status;
519 cur_frame_end[-3] = next_frame_end_offset;
520 cur_frame_end[-2] = count;
521 next_frame_end_offset = cur_frame_end_offset;
522 cur_frame_end_offset -= ((count + 1)>>1) + 3;
523 if (cur_frame_end_offset < 0)
524 cur_frame_end_offset += RX_BUF_SIZE8192/2;
525 };
526
527 /* Now step forward through the list. */
528 do {
529 ushort *this_rfp_ptr = zn.rx_start + next_frame_end_offset;
530 int status = this_rfp_ptr[-4];
531 int pkt_len = this_rfp_ptr[-2];
532
533 if (znet_debug > 5)
534 printk(KERN_DEBUG"<7>" "Looking at trailer ending at %04x status %04x length %03x"
535 " next %04x.\n", next_frame_end_offset<<1, status, pkt_len,
536 this_rfp_ptr[-3]<<1);
537 /* Once again we must assume that the i82586 docs apply. */
538 if ( ! (status & 0x2000)) { /* There was an error. */
539 lp->stats.rx_errors++;
540 if (status & 0x0800) lp->stats.rx_crc_errors++;
541 if (status & 0x0400) lp->stats.rx_frame_errors++;
542 if (status & 0x0200) lp->stats.rx_over_errors++; /* Wrong. */
543 if (status & 0x0100) lp->stats.rx_fifo_errors++;
544 if (status & 0x0080) lp->stats.rx_length_errors++;
545 } else if (pkt_len > 1536) {
546 lp->stats.rx_length_errors++;
547 } else {
548 /* Malloc up new buffer. */
549 struct sk_buff *skb;
550
551 skb = dev_alloc_skb(pkt_len);
552 if (skb == NULL((void *) 0)) {
553 if (znet_debug)
554 printk(KERN_WARNING"<4>" "%s: Memory squeeze, dropping packet.\n", dev->name);
555 lp->stats.rx_dropped++;
556 break;
557 }
558 skb->dev = dev;
559
560 if (&zn.rx_cur[(pkt_len+1)>>1] > zn.rx_end) {
561 int semi_cnt = (zn.rx_end - zn.rx_cur)<<1;
562 memcpy(skb_put(skb,semi_cnt), zn.rx_cur, semi_cnt)(__builtin_constant_p(semi_cnt) ? __constant_memcpy((skb_put(
skb,semi_cnt)),(zn.rx_cur),(semi_cnt)) : __memcpy((skb_put(skb
,semi_cnt)),(zn.rx_cur),(semi_cnt)));
563 memcpy(skb_put(skb,pkt_len-semi_cnt), zn.rx_start,(__builtin_constant_p(pkt_len - semi_cnt) ? __constant_memcpy
((skb_put(skb,pkt_len-semi_cnt)),(zn.rx_start),(pkt_len - semi_cnt
)) : __memcpy((skb_put(skb,pkt_len-semi_cnt)),(zn.rx_start),(
pkt_len - semi_cnt)))
564 pkt_len - semi_cnt)(__builtin_constant_p(pkt_len - semi_cnt) ? __constant_memcpy
((skb_put(skb,pkt_len-semi_cnt)),(zn.rx_start),(pkt_len - semi_cnt
)) : __memcpy((skb_put(skb,pkt_len-semi_cnt)),(zn.rx_start),(
pkt_len - semi_cnt)));
565 } else {
566 memcpy(skb_put(skb,pkt_len), zn.rx_cur, pkt_len)(__builtin_constant_p(pkt_len) ? __constant_memcpy((skb_put(skb
,pkt_len)),(zn.rx_cur),(pkt_len)) : __memcpy((skb_put(skb,pkt_len
)),(zn.rx_cur),(pkt_len)));
567 if (znet_debug > 6) {
568 unsigned int *packet = (unsigned int *) skb->data;
569 printk(KERN_DEBUG"<7>" "Packet data is %08x %08x %08x %08x.\n", packet[0],
570 packet[1], packet[2], packet[3]);
571 }
572 }
573 skb->protocol=eth_type_trans(skb,dev)((unsigned short)0);
574 netif_rx(skb);
575 lp->stats.rx_packets++;
576 }
577 zn.rx_cur = this_rfp_ptr;
578 if (zn.rx_cur >= zn.rx_end)
579 zn.rx_cur -= RX_BUF_SIZE8192/2;
580 update_stop_hit(ioaddr, (zn.rx_cur - zn.rx_start)<<1);
581 next_frame_end_offset = this_rfp_ptr[-3];
582 if (next_frame_end_offset == 0) /* Read all the frames? */
583 break; /* Done for now */
584 this_rfp_ptr = zn.rx_start + next_frame_end_offset;
Value stored to 'this_rfp_ptr' is never read
585 } while (--boguscount);
586
587 /* If any worth-while packets have been received, dev_rint()
588 has done a mark_bh(INET_BH) for us and will work on them
589 when we get to the bottom-half routine. */
590 return;
591}
592
593/* The inverse routine to znet_open(). */
594static int znet_close(struct devicelinux_device *dev)
595{
596 int ioaddr = dev->base_addr;
597
598 dev->tbusy = 1;
599 dev->start = 0;
600
601 outb(CMD0_RESET, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((14),(ioaddr)) : __outb((14),(ioaddr))); /* CMD0_RESET */
602
603 disable_dma(zn.rx_dma);
604 disable_dma(zn.tx_dma);
605
606 free_irq(dev->irq, NULL((void *) 0));
607
608 if (znet_debug > 1)
609 printk(KERN_DEBUG"<7>" "%s: Shutting down ethercard.\n", dev->name);
610 /* Turn off transceiver power. */
611 outb(0x10, 0xe6)((__builtin_constant_p((0xe6)) && (0xe6) < 256) ? __outbc
((0x10),(0xe6)) : __outb((0x10),(0xe6))); /* Select LAN control register */
612 outb(inb(0xe7) & ~0x84, 0xe7)((__builtin_constant_p((0xe7)) && (0xe7) < 256) ? __outbc
((((__builtin_constant_p((0xe7)) && (0xe7) < 256) ?
__inbc(0xe7) : __inb(0xe7)) & ~0x84),(0xe7)) : __outb(((
(__builtin_constant_p((0xe7)) && (0xe7) < 256) ? __inbc
(0xe7) : __inb(0xe7)) & ~0x84),(0xe7))); /* Turn on LAN power (bit 2). */
613
614 return 0;
615}
616
617/* Get the current statistics. This may be called with the card open or
618 closed. */
619static struct enet_statistics *net_get_stats(struct devicelinux_device *dev)
620{
621 struct net_localznet_private *lp = (struct net_localznet_private *)dev->priv;
622
623 return &lp->stats;
624}
625
626/* Set or clear the multicast filter for this adaptor.
627 As a side effect this routine must also initialize the device parameters.
628 This is taken advantage of in open().
629
630 N.B. that we change i593_init[] in place. This (properly) makes the
631 mode change persistent, but must be changed if this code is moved to
632 a multiple adaptor environment.
633 */
634static void set_multicast_list(struct devicelinux_device *dev)
635{
636 short ioaddr = dev->base_addr;
637
638 if (dev->flags&IFF_PROMISC0x100) {
639 /* Enable promiscuous mode */
640 i593_init[7] &= ~3; i593_init[7] |= 1;
641 i593_init[13] &= ~8; i593_init[13] |= 8;
642 } else if (dev->mc_list || (dev->flags&IFF_ALLMULTI0x200)) {
643 /* Enable accept-all-multicast mode */
644 i593_init[7] &= ~3; i593_init[7] |= 0;
645 i593_init[13] &= ~8; i593_init[13] |= 8;
646 } else { /* Enable normal mode. */
647 i593_init[7] &= ~3; i593_init[7] |= 0;
648 i593_init[13] &= ~8; i593_init[13] |= 0;
649 }
650 *zn.tx_cur++ = sizeof(i593_init);
651 memcpy(zn.tx_cur, i593_init, sizeof(i593_init))(__builtin_constant_p(sizeof(i593_init)) ? __constant_memcpy(
(zn.tx_cur),(i593_init),(sizeof(i593_init))) : __memcpy((zn.tx_cur
),(i593_init),(sizeof(i593_init))));
652 zn.tx_cur += sizeof(i593_init)/2;
653 outb(CMD0_CONFIGURE+CMD0_CHNL_1, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((2 +0x10),(ioaddr)) : __outb((2 +0x10),(ioaddr)));
654#ifdef not_tested
655 if (num_addrs > 0) {
656 int addrs_len = 6*num_addrs;
657 *zn.tx_cur++ = addrs_len;
658 memcpy(zn.tx_cur, addrs, addrs_len)(__builtin_constant_p(addrs_len) ? __constant_memcpy((zn.tx_cur
),(addrs),(addrs_len)) : __memcpy((zn.tx_cur),(addrs),(addrs_len
)));
659 outb(CMD0_MULTICAST_LIST+CMD0_CHNL_1, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((3 +0x10),(ioaddr)) : __outb((3 +0x10),(ioaddr)));
660 zn.tx_cur += addrs_len>>1;
661 }
662#endif
663}
664
665void show_dma(void)
666{
667 short dma_port = ((zn.tx_dma&3)<<2) + IO_DMA2_BASE0xC0;
668 unsigned addr = inb(dma_port)((__builtin_constant_p((dma_port)) && (dma_port) <
256) ? __inbc(dma_port) : __inb(dma_port));
669 addr |= inb(dma_port)((__builtin_constant_p((dma_port)) && (dma_port) <
256) ? __inbc(dma_port) : __inb(dma_port)) << 8;
670 printk("Addr: %04x cnt:%3x...", addr<<1, get_dma_residue(zn.tx_dma));
671}
672
673/* Initialize the hardware. We have to do this when the board is open()ed
674 or when we come out of suspend mode. */
675static void hardware_init(struct devicelinux_device *dev)
676{
677 short ioaddr = dev->base_addr;
678
679 zn.rx_cur = zn.rx_start;
680 zn.tx_cur = zn.tx_start;
681
682 /* Reset the chip, and start it up. */
683 outb(CMD0_RESET, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((14),(ioaddr)) : __outb((14),(ioaddr)));
684
685 cli()__asm__ __volatile__ ("cli": : :"memory"); { /* Protect against a DMA flip-flop */
686 disable_dma(zn.rx_dma); /* reset by an interrupting task. */
687 clear_dma_ff(zn.rx_dma);
688 set_dma_mode(zn.rx_dma, DMA_RX_MODE0x14);
689 set_dma_addr(zn.rx_dma, (unsigned int) zn.rx_start);
690 set_dma_count(zn.rx_dma, RX_BUF_SIZE8192);
691 enable_dma(zn.rx_dma);
692 /* Now set up the Tx channel. */
693 disable_dma(zn.tx_dma);
694 clear_dma_ff(zn.tx_dma);
695 set_dma_mode(zn.tx_dma, DMA_TX_MODE0x18);
696 set_dma_addr(zn.tx_dma, (unsigned int) zn.tx_start);
697 set_dma_count(zn.tx_dma, zn.tx_buf_len<<1);
698 enable_dma(zn.tx_dma);
699 } sti()__asm__ __volatile__ ("sti": : :"memory");
700
701 if (znet_debug > 1)
702 printk(KERN_DEBUG"<7>" "%s: Initializing the i82593, tx buf %p... ", dev->name,
703 zn.tx_start);
704 /* Do an empty configure command, just like the Crynwr driver. This
705 resets to chip to its default values. */
706 *zn.tx_cur++ = 0;
707 *zn.tx_cur++ = 0;
708 printk("stat:%02x ", inb(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inbc(ioaddr) : __inb(ioaddr))); show_dma();
709 outb(CMD0_CONFIGURE+CMD0_CHNL_1, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((2 +0x10),(ioaddr)) : __outb((2 +0x10),(ioaddr)));
710 *zn.tx_cur++ = sizeof(i593_init);
711 memcpy(zn.tx_cur, i593_init, sizeof(i593_init))(__builtin_constant_p(sizeof(i593_init)) ? __constant_memcpy(
(zn.tx_cur),(i593_init),(sizeof(i593_init))) : __memcpy((zn.tx_cur
),(i593_init),(sizeof(i593_init))));
712 zn.tx_cur += sizeof(i593_init)/2;
713 printk("stat:%02x ", inb(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inbc(ioaddr) : __inb(ioaddr))); show_dma();
714 outb(CMD0_CONFIGURE+CMD0_CHNL_1, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((2 +0x10),(ioaddr)) : __outb((2 +0x10),(ioaddr)));
715 *zn.tx_cur++ = 6;
716 memcpy(zn.tx_cur, dev->dev_addr, 6)(__builtin_constant_p(6) ? __constant_memcpy((zn.tx_cur),(dev
->dev_addr),(6)) : __memcpy((zn.tx_cur),(dev->dev_addr)
,(6)));
717 zn.tx_cur += 3;
718 printk("stat:%02x ", inb(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inbc(ioaddr) : __inb(ioaddr))); show_dma();
719 outb(CMD0_IA_SETUP + CMD0_CHNL_1, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((1 + 0x10),(ioaddr)) : __outb((1 + 0x10),(ioaddr)
));
720 printk("stat:%02x ", inb(ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __inbc(ioaddr) : __inb(ioaddr))); show_dma();
721
722 update_stop_hit(ioaddr, 8192);
723 if (znet_debug > 1) printk("enabling Rx.\n");
724 outb(CMD0_Rx_ENABLE+CMD0_CHNL_0, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((8 +0x00),(ioaddr)) : __outb((8 +0x00),(ioaddr)));
725 dev->tbusy = 0;
726}
727
728static void update_stop_hit(short ioaddr, unsigned short rx_stop_offset)
729{
730 outb(CMD0_PORT_1, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((0x10),(ioaddr)) : __outb((0x10),(ioaddr)));
731 if (znet_debug > 5)
732 printk(KERN_DEBUG"<7>" "Updating stop hit with value %02x.\n",
733 (rx_stop_offset >> 6) | 0x80);
734 outb((rx_stop_offset >> 6) | 0x80, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc(((rx_stop_offset >> 6) | 0x80),(ioaddr)) : __outb
(((rx_stop_offset >> 6) | 0x80),(ioaddr)));
735 outb(CMD1_PORT_0, ioaddr)((__builtin_constant_p((ioaddr)) && (ioaddr) < 256
) ? __outbc((1),(ioaddr)) : __outb((1),(ioaddr)));
736}
737
738/*
739 * Local variables:
740 * compile-command: "gcc -D__KERNEL__ -I/usr/src/linux/net/inet -Wall -Wstrict-prototypes -O6 -m486 -c znet.c"
741 * version-control: t
742 * kept-new-versions: 5
743 * c-indent-level: 4
744 * tab-width: 4
745 * End:
746 */