1/*
2 *  Copyright (C) 2002 Intersil Americas Inc.
3 *  Copyright 2004 Jens Maurer <Jens.Maurer@gmx.net>
4 *
5 *  This program is free software; you can redistribute it and/or modify
6 *  it under the terms of the GNU General Public License as published by
7 *  the Free Software Foundation; either version 2 of the License
8 *
9 *  This program is distributed in the hope that it will be useful,
10 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
11 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 *  GNU General Public License for more details.
13 *
14 *  You should have received a copy of the GNU General Public License
15 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
16 *
17 */
18
19#include <linux/netdevice.h>
20#include <linux/module.h>
21#include <linux/pci.h>
22#include <linux/sched.h>
23#include <linux/slab.h>
24
25#include <asm/io.h>
26#include <linux/if_arp.h>
27
28#include "prismcompat.h"
29#include "isl_38xx.h"
30#include "islpci_mgt.h"
31#include "isl_oid.h"		/* additional types and defs for isl38xx fw */
32#include "isl_ioctl.h"
33
34#include <net/iw_handler.h>
35
36/******************************************************************************
37        Global variable definition section
38******************************************************************************/
39int pc_debug = VERBOSE;
40module_param(pc_debug, int, 0);
41
42/******************************************************************************
43    Driver general functions
44******************************************************************************/
45#if VERBOSE > SHOW_ERROR_MESSAGES
46void
47display_buffer(char *buffer, int length)
48{
49	if ((pc_debug & SHOW_BUFFER_CONTENTS) == 0)
50		return;
51
52	while (length > 0) {
53		printk("[%02x]", *buffer & 255);
54		length--;
55		buffer++;
56	}
57
58	printk("\n");
59}
60#endif
61
62/*****************************************************************************
63    Queue handling for management frames
64******************************************************************************/
65
66/*
67 * Helper function to create a PIMFOR management frame header.
68 */
69static void
70pimfor_encode_header(int operation, u32 oid, u32 length, pimfor_header_t *h)
71{
72	h->version = PIMFOR_VERSION;
73	h->operation = operation;
74	h->device_id = PIMFOR_DEV_ID_MHLI_MIB;
75	h->flags = 0;
76	h->oid = cpu_to_be32(oid);
77	h->length = cpu_to_be32(length);
78}
79
80/*
81 * Helper function to analyze a PIMFOR management frame header.
82 */
83static pimfor_header_t *
84pimfor_decode_header(void *data, int len)
85{
86	pimfor_header_t *h = data;
87
88	while ((void *) h < data + len) {
89		if (h->flags & PIMFOR_FLAG_LITTLE_ENDIAN) {
90			le32_to_cpus(&h->oid);
91			le32_to_cpus(&h->length);
92		} else {
93			be32_to_cpus(&h->oid);
94			be32_to_cpus(&h->length);
95		}
96		if (h->oid != OID_INL_TUNNEL)
97			return h;
98		h++;
99	}
100	return NULL;
101}
102
103/*
104 * Fill the receive queue for management frames with fresh buffers.
105 */
106int
107islpci_mgmt_rx_fill(struct net_device *ndev)
108{
109	islpci_private *priv = netdev_priv(ndev);
110	isl38xx_control_block *cb =	/* volatile not needed */
111	    (isl38xx_control_block *) priv->control_block;
112	u32 curr = le32_to_cpu(cb->driver_curr_frag[ISL38XX_CB_RX_MGMTQ]);
113
114#if VERBOSE > SHOW_ERROR_MESSAGES
115	DEBUG(SHOW_FUNCTION_CALLS, "islpci_mgmt_rx_fill\n");
116#endif
117
118	while (curr - priv->index_mgmt_rx < ISL38XX_CB_MGMT_QSIZE) {
119		u32 index = curr % ISL38XX_CB_MGMT_QSIZE;
120		struct islpci_membuf *buf = &priv->mgmt_rx[index];
121		isl38xx_fragment *frag = &cb->rx_data_mgmt[index];
122
123		if (buf->mem == NULL) {
124			buf->mem = kmalloc(MGMT_FRAME_SIZE, GFP_ATOMIC);
125			if (!buf->mem)
126				return -ENOMEM;
127			buf->size = MGMT_FRAME_SIZE;
128		}
129		if (buf->pci_addr == 0) {
130			buf->pci_addr = pci_map_single(priv->pdev, buf->mem,
131						       MGMT_FRAME_SIZE,
132						       PCI_DMA_FROMDEVICE);
133			if (!buf->pci_addr) {
134				printk(KERN_WARNING
135				       "Failed to make memory DMA'able.\n");
136				return -ENOMEM;
137			}
138		}
139
140		/* be safe: always reset control block information */
141		frag->size = cpu_to_le16(MGMT_FRAME_SIZE);
142		frag->flags = 0;
143		frag->address = cpu_to_le32(buf->pci_addr);
144		curr++;
145
146		/* The fragment address in the control block must have
147		 * been written before announcing the frame buffer to
148		 * device */
149		wmb();
150		cb->driver_curr_frag[ISL38XX_CB_RX_MGMTQ] = cpu_to_le32(curr);
151	}
152	return 0;
153}
154
155/*
156 * Create and transmit a management frame using "operation" and "oid",
157 * with arguments data/length.
158 * We either return an error and free the frame, or we return 0 and
159 * islpci_mgt_cleanup_transmit() frees the frame in the tx-done
160 * interrupt.
161 */
162static int
163islpci_mgt_transmit(struct net_device *ndev, int operation, unsigned long oid,
164		    void *data, int length)
165{
166	islpci_private *priv = netdev_priv(ndev);
167	isl38xx_control_block *cb =
168	    (isl38xx_control_block *) priv->control_block;
169	void *p;
170	int err = -EINVAL;
171	unsigned long flags;
172	isl38xx_fragment *frag;
173	struct islpci_membuf buf;
174	u32 curr_frag;
175	int index;
176	int frag_len = length + PIMFOR_HEADER_SIZE;
177
178#if VERBOSE > SHOW_ERROR_MESSAGES
179	DEBUG(SHOW_FUNCTION_CALLS, "islpci_mgt_transmit\n");
180#endif
181
182	if (frag_len > MGMT_FRAME_SIZE) {
183		printk(KERN_DEBUG "%s: mgmt frame too large %d\n",
184		       ndev->name, frag_len);
185		goto error;
186	}
187
188	err = -ENOMEM;
189	p = buf.mem = kmalloc(frag_len, GFP_KERNEL);
190	if (!buf.mem)
191		goto error;
192
193	buf.size = frag_len;
194
195	/* create the header directly in the fragment data area */
196	pimfor_encode_header(operation, oid, length, (pimfor_header_t *) p);
197	p += PIMFOR_HEADER_SIZE;
198
199	if (data)
200		memcpy(p, data, length);
201	else
202		memset(p, 0, length);
203
204#if VERBOSE > SHOW_ERROR_MESSAGES
205	{
206		pimfor_header_t *h = buf.mem;
207		DEBUG(SHOW_PIMFOR_FRAMES,
208		      "PIMFOR: op %i, oid 0x%08lx, device %i, flags 0x%x length 0x%x\n",
209		      h->operation, oid, h->device_id, h->flags, length);
210
211		/* display the buffer contents for debugging */
212		display_buffer((char *) h, sizeof (pimfor_header_t));
213		display_buffer(p, length);
214	}
215#endif
216
217	err = -ENOMEM;
218	buf.pci_addr = pci_map_single(priv->pdev, buf.mem, frag_len,
219				      PCI_DMA_TODEVICE);
220	if (!buf.pci_addr) {
221		printk(KERN_WARNING "%s: cannot map PCI memory for mgmt\n",
222		       ndev->name);
223		goto error_free;
224	}
225
226	/* Protect the control block modifications against interrupts. */
227	spin_lock_irqsave(&priv->slock, flags);
228	curr_frag = le32_to_cpu(cb->driver_curr_frag[ISL38XX_CB_TX_MGMTQ]);
229	if (curr_frag - priv->index_mgmt_tx >= ISL38XX_CB_MGMT_QSIZE) {
230		printk(KERN_WARNING "%s: mgmt tx queue is still full\n",
231		       ndev->name);
232		goto error_unlock;
233	}
234
235	/* commit the frame to the tx device queue */
236	index = curr_frag % ISL38XX_CB_MGMT_QSIZE;
237	priv->mgmt_tx[index] = buf;
238	frag = &cb->tx_data_mgmt[index];
239	frag->size = cpu_to_le16(frag_len);
240	frag->flags = 0;	/* for any other than the last fragment, set to 1 */
241	frag->address = cpu_to_le32(buf.pci_addr);
242
243	/* The fragment address in the control block must have
244	 * been written before announcing the frame buffer to
245	 * device */
246	wmb();
247	cb->driver_curr_frag[ISL38XX_CB_TX_MGMTQ] = cpu_to_le32(curr_frag + 1);
248	spin_unlock_irqrestore(&priv->slock, flags);
249
250	/* trigger the device */
251	islpci_trigger(priv);
252	return 0;
253
254      error_unlock:
255	spin_unlock_irqrestore(&priv->slock, flags);
256      error_free:
257	kfree(buf.mem);
258      error:
259	return err;
260}
261
262/*
263 * Receive a management frame from the device.
264 * This can be an arbitrary number of traps, and at most one response
265 * frame for a previous request sent via islpci_mgt_transmit().
266 */
267int
268islpci_mgt_receive(struct net_device *ndev)
269{
270	islpci_private *priv = netdev_priv(ndev);
271	isl38xx_control_block *cb =
272	    (isl38xx_control_block *) priv->control_block;
273	u32 curr_frag;
274
275#if VERBOSE > SHOW_ERROR_MESSAGES
276	DEBUG(SHOW_FUNCTION_CALLS, "islpci_mgt_receive\n");
277#endif
278
279	/* Only once per interrupt, determine fragment range to
280	 * process.  This avoids an endless loop (i.e. lockup) if
281	 * frames come in faster than we can process them. */
282	curr_frag = le32_to_cpu(cb->device_curr_frag[ISL38XX_CB_RX_MGMTQ]);
283	barrier();
284
285	for (; priv->index_mgmt_rx < curr_frag; priv->index_mgmt_rx++) {
286		pimfor_header_t *header;
287		u32 index = priv->index_mgmt_rx % ISL38XX_CB_MGMT_QSIZE;
288		struct islpci_membuf *buf = &priv->mgmt_rx[index];
289		u16 frag_len;
290		int size;
291		struct islpci_mgmtframe *frame;
292
293		/* I have no idea (and no documentation) if flags != 0
294		 * is possible.  Drop the frame, reuse the buffer. */
295		if (le16_to_cpu(cb->rx_data_mgmt[index].flags) != 0) {
296			printk(KERN_WARNING "%s: unknown flags 0x%04x\n",
297			       ndev->name,
298			       le16_to_cpu(cb->rx_data_mgmt[index].flags));
299			continue;
300		}
301
302		/* The device only returns the size of the header(s) here. */
303		frag_len = le16_to_cpu(cb->rx_data_mgmt[index].size);
304
305		/*
306		 * We appear to have no way to tell the device the
307		 * size of a receive buffer.  Thus, if this check
308		 * triggers, we likely have kernel heap corruption. */
309		if (frag_len > MGMT_FRAME_SIZE) {
310			printk(KERN_WARNING
311				"%s: Bogus packet size of %d (%#x).\n",
312				ndev->name, frag_len, frag_len);
313			frag_len = MGMT_FRAME_SIZE;
314		}
315
316		/* Ensure the results of device DMA are visible to the CPU. */
317		pci_dma_sync_single_for_cpu(priv->pdev, buf->pci_addr,
318					    buf->size, PCI_DMA_FROMDEVICE);
319
320		/* Perform endianess conversion for PIMFOR header in-place. */
321		header = pimfor_decode_header(buf->mem, frag_len);
322		if (!header) {
323			printk(KERN_WARNING "%s: no PIMFOR header found\n",
324			       ndev->name);
325			continue;
326		}
327
328		/* The device ID from the PIMFOR packet received from
329		 * the MVC is always 0.  We forward a sensible device_id.
330		 * Not that anyone upstream would care... */
331		header->device_id = priv->ndev->ifindex;
332
333#if VERBOSE > SHOW_ERROR_MESSAGES
334		DEBUG(SHOW_PIMFOR_FRAMES,
335		      "PIMFOR: op %i, oid 0x%08x, device %i, flags 0x%x length 0x%x\n",
336		      header->operation, header->oid, header->device_id,
337		      header->flags, header->length);
338
339		/* display the buffer contents for debugging */
340		display_buffer((char *) header, PIMFOR_HEADER_SIZE);
341		display_buffer((char *) header + PIMFOR_HEADER_SIZE,
342			       header->length);
343#endif
344
345		/* nobody sends these */
346		if (header->flags & PIMFOR_FLAG_APPLIC_ORIGIN) {
347			printk(KERN_DEBUG
348			       "%s: errant PIMFOR application frame\n",
349			       ndev->name);
350			continue;
351		}
352
353		/* Determine frame size, skipping OID_INL_TUNNEL headers. */
354		size = PIMFOR_HEADER_SIZE + header->length;
355		frame = kmalloc(sizeof(struct islpci_mgmtframe) + size,
356				GFP_ATOMIC);
357		if (!frame)
358			continue;
359
360		frame->ndev = ndev;
361		memcpy(&frame->buf, header, size);
362		frame->header = (pimfor_header_t *) frame->buf;
363		frame->data = frame->buf + PIMFOR_HEADER_SIZE;
364
365#if VERBOSE > SHOW_ERROR_MESSAGES
366		DEBUG(SHOW_PIMFOR_FRAMES,
367		      "frame: header: %p, data: %p, size: %d\n",
368		      frame->header, frame->data, size);
369#endif
370
371		if (header->operation == PIMFOR_OP_TRAP) {
372#if VERBOSE > SHOW_ERROR_MESSAGES
373			printk(KERN_DEBUG
374			       "TRAP: oid 0x%x, device %i, flags 0x%x length %i\n",
375			       header->oid, header->device_id, header->flags,
376			       header->length);
377#endif
378
379			/* Create work to handle trap out of interrupt
380			 * context. */
381			INIT_WORK(&frame->ws, prism54_process_trap);
382			schedule_work(&frame->ws);
383
384		} else {
385			/* Signal the one waiting process that a response
386			 * has been received. */
387			if ((frame = xchg(&priv->mgmt_received, frame)) != NULL) {
388				printk(KERN_WARNING
389				       "%s: mgmt response not collected\n",
390				       ndev->name);
391				kfree(frame);
392			}
393#if VERBOSE > SHOW_ERROR_MESSAGES
394			DEBUG(SHOW_TRACING, "Wake up Mgmt Queue\n");
395#endif
396			wake_up(&priv->mgmt_wqueue);
397		}
398
399	}
400
401	return 0;
402}
403
404/*
405 * Cleanup the transmit queue by freeing all frames handled by the device.
406 */
407void
408islpci_mgt_cleanup_transmit(struct net_device *ndev)
409{
410	islpci_private *priv = netdev_priv(ndev);
411	isl38xx_control_block *cb =	/* volatile not needed */
412	    (isl38xx_control_block *) priv->control_block;
413	u32 curr_frag;
414
415#if VERBOSE > SHOW_ERROR_MESSAGES
416	DEBUG(SHOW_FUNCTION_CALLS, "islpci_mgt_cleanup_transmit\n");
417#endif
418
419	/* Only once per cleanup, determine fragment range to
420	 * process.  This avoids an endless loop (i.e. lockup) if
421	 * the device became confused, incrementing device_curr_frag
422	 * rapidly. */
423	curr_frag = le32_to_cpu(cb->device_curr_frag[ISL38XX_CB_TX_MGMTQ]);
424	barrier();
425
426	for (; priv->index_mgmt_tx < curr_frag; priv->index_mgmt_tx++) {
427		int index = priv->index_mgmt_tx % ISL38XX_CB_MGMT_QSIZE;
428		struct islpci_membuf *buf = &priv->mgmt_tx[index];
429		pci_unmap_single(priv->pdev, buf->pci_addr, buf->size,
430				 PCI_DMA_TODEVICE);
431		buf->pci_addr = 0;
432		kfree(buf->mem);
433		buf->mem = NULL;
434		buf->size = 0;
435	}
436}
437
438/*
439 * Perform one request-response transaction to the device.
440 */
441int
442islpci_mgt_transaction(struct net_device *ndev,
443		       int operation, unsigned long oid,
444		       void *senddata, int sendlen,
445		       struct islpci_mgmtframe **recvframe)
446{
447	islpci_private *priv = netdev_priv(ndev);
448	const long wait_cycle_jiffies = msecs_to_jiffies(ISL38XX_WAIT_CYCLE * 10);
449	long timeout_left = ISL38XX_MAX_WAIT_CYCLES * wait_cycle_jiffies;
450	int err;
451	DEFINE_WAIT(wait);
452
453	*recvframe = NULL;
454
455	if (mutex_lock_interruptible(&priv->mgmt_lock))
456		return -ERESTARTSYS;
457
458	prepare_to_wait(&priv->mgmt_wqueue, &wait, TASK_UNINTERRUPTIBLE);
459	err = islpci_mgt_transmit(ndev, operation, oid, senddata, sendlen);
460	if (err)
461		goto out;
462
463	err = -ETIMEDOUT;
464	while (timeout_left > 0) {
465		int timeleft;
466		struct islpci_mgmtframe *frame;
467
468		timeleft = schedule_timeout_uninterruptible(wait_cycle_jiffies);
469		frame = xchg(&priv->mgmt_received, NULL);
470		if (frame) {
471			if (frame->header->oid == oid) {
472				*recvframe = frame;
473				err = 0;
474				goto out;
475			} else {
476				printk(KERN_DEBUG
477				       "%s: expecting oid 0x%x, received 0x%x.\n",
478				       ndev->name, (unsigned int) oid,
479				       frame->header->oid);
480				kfree(frame);
481				frame = NULL;
482			}
483		}
484		if (timeleft == 0) {
485			printk(KERN_DEBUG
486				"%s: timeout waiting for mgmt response %lu, "
487				"triggering device\n",
488				ndev->name, timeout_left);
489			islpci_trigger(priv);
490		}
491		timeout_left += timeleft - wait_cycle_jiffies;
492	}
493	printk(KERN_WARNING "%s: timeout waiting for mgmt response\n",
494	       ndev->name);
495
496	/* TODO: we should reset the device here */
497 out:
498	finish_wait(&priv->mgmt_wqueue, &wait);
499	mutex_unlock(&priv->mgmt_lock);
500	return err;
501}
502
503