blob: 466147e409c9062bc61069aac6111d1be0e92658 [file] [log] [blame]
Raghu Vatsavayif21fb3e2015-06-09 18:15:23 -07001/**********************************************************************
2* Author: Cavium, Inc.
3*
4* Contact: support@cavium.com
5* Please include "LiquidIO" in the subject.
6*
7* Copyright (c) 2003-2015 Cavium, Inc.
8*
9* This file is free software; you can redistribute it and/or modify
10* it under the terms of the GNU General Public License, Version 2, as
11* published by the Free Software Foundation.
12*
13* This file is distributed in the hope that it will be useful, but
14* AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
15* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
16* NONINFRINGEMENT. See the GNU General Public License for more
17* details.
18*
19* This file may also be available under a different license from Cavium.
20* Contact Cavium, Inc. for more information
21**********************************************************************/
22
23/**
24 * @file octeon_console.c
25 */
26#include <linux/version.h>
27#include <linux/types.h>
28#include <linux/list.h>
29#include <linux/interrupt.h>
30#include <linux/pci.h>
31#include <linux/kthread.h>
32#include <linux/netdevice.h>
33#include "octeon_config.h"
34#include "liquidio_common.h"
35#include "octeon_droq.h"
36#include "octeon_iq.h"
37#include "response_manager.h"
38#include "octeon_device.h"
39#include "octeon_nic.h"
40#include "octeon_main.h"
41#include "octeon_network.h"
42#include "cn66xx_regs.h"
43#include "cn66xx_device.h"
44#include "cn68xx_regs.h"
45#include "cn68xx_device.h"
46#include "liquidio_image.h"
47#include "octeon_mem_ops.h"
48
49static void octeon_remote_lock(void);
50static void octeon_remote_unlock(void);
51static u64 cvmx_bootmem_phy_named_block_find(struct octeon_device *oct,
52 const char *name,
53 u32 flags);
54
55#define MIN(a, b) min((a), (b))
56#define CAST_ULL(v) ((u64)(v))
57
58#define BOOTLOADER_PCI_READ_BUFFER_DATA_ADDR 0x0006c008
59#define BOOTLOADER_PCI_READ_BUFFER_LEN_ADDR 0x0006c004
60#define BOOTLOADER_PCI_READ_BUFFER_OWNER_ADDR 0x0006c000
61#define BOOTLOADER_PCI_READ_DESC_ADDR 0x0006c100
62#define BOOTLOADER_PCI_WRITE_BUFFER_STR_LEN 248
63
64#define OCTEON_PCI_IO_BUF_OWNER_OCTEON 0x00000001
65#define OCTEON_PCI_IO_BUF_OWNER_HOST 0x00000002
66
67/** Can change without breaking ABI */
68#define CVMX_BOOTMEM_NUM_NAMED_BLOCKS 64
69
70/** minimum alignment of bootmem alloced blocks */
71#define CVMX_BOOTMEM_ALIGNMENT_SIZE (16ull)
72
73/** CVMX bootmem descriptor major version */
74#define CVMX_BOOTMEM_DESC_MAJ_VER 3
75/* CVMX bootmem descriptor minor version */
76#define CVMX_BOOTMEM_DESC_MIN_VER 0
77
78/* Current versions */
79#define OCTEON_PCI_CONSOLE_MAJOR_VERSION 1
80#define OCTEON_PCI_CONSOLE_MINOR_VERSION 0
81#define OCTEON_PCI_CONSOLE_BLOCK_NAME "__pci_console"
82#define OCTEON_CONSOLE_POLL_INTERVAL_MS 100 /* 10 times per second */
83
84/* First three members of cvmx_bootmem_desc are left in original
85** positions for backwards compatibility.
86** Assumes big endian target
87*/
88struct cvmx_bootmem_desc {
89 /** spinlock to control access to list */
90 u32 lock;
91
92 /** flags for indicating various conditions */
93 u32 flags;
94
95 u64 head_addr;
96
97 /** incremented changed when incompatible changes made */
98 u32 major_version;
99
100 /** incremented changed when compatible changes made,
101 * reset to zero when major incremented
102 */
103 u32 minor_version;
104
105 u64 app_data_addr;
106 u64 app_data_size;
107
108 /** number of elements in named blocks array */
109 u32 nb_num_blocks;
110
111 /** length of name array in bootmem blocks */
112 u32 named_block_name_len;
113
114 /** address of named memory block descriptors */
115 u64 named_block_array_addr;
116};
117
118/* Structure that defines a single console.
119 *
120 * Note: when read_index == write_index, the buffer is empty.
121 * The actual usable size of each console is console_buf_size -1;
122 */
123struct octeon_pci_console {
124 u64 input_base_addr;
125 u32 input_read_index;
126 u32 input_write_index;
127 u64 output_base_addr;
128 u32 output_read_index;
129 u32 output_write_index;
130 u32 lock;
131 u32 buf_size;
132};
133
134/* This is the main container structure that contains all the information
135 * about all PCI consoles. The address of this structure is passed to various
136 * routines that operation on PCI consoles.
137 */
138struct octeon_pci_console_desc {
139 u32 major_version;
140 u32 minor_version;
141 u32 lock;
142 u32 flags;
143 u32 num_consoles;
144 u32 pad;
145 /* must be 64 bit aligned here... */
146 /* Array of addresses of octeon_pci_console structures */
147 u64 console_addr_array[0];
148 /* Implicit storage for console_addr_array */
149};
150
151/**
152 * This macro returns the size of a member of a structure.
153 * Logically it is the same as "sizeof(s::field)" in C++, but
154 * C lacks the "::" operator.
155 */
156#define SIZEOF_FIELD(s, field) sizeof(((s *)NULL)->field)
157
158/**
159 * This macro returns a member of the cvmx_bootmem_desc
160 * structure. These members can't be directly addressed as
161 * they might be in memory not directly reachable. In the case
162 * where bootmem is compiled with LINUX_HOST, the structure
163 * itself might be located on a remote Octeon. The argument
164 * "field" is the member name of the cvmx_bootmem_desc to read.
165 * Regardless of the type of the field, the return type is always
166 * a u64.
167 */
168#define CVMX_BOOTMEM_DESC_GET_FIELD(oct, field) \
169 __cvmx_bootmem_desc_get(oct, oct->bootmem_desc_addr, \
170 offsetof(struct cvmx_bootmem_desc, field), \
171 SIZEOF_FIELD(struct cvmx_bootmem_desc, field))
172
173#define __cvmx_bootmem_lock(flags)
174#define __cvmx_bootmem_unlock(flags)
175
176/**
177 * This macro returns a member of the
178 * cvmx_bootmem_named_block_desc structure. These members can't
179 * be directly addressed as they might be in memory not directly
180 * reachable. In the case where bootmem is compiled with
181 * LINUX_HOST, the structure itself might be located on a remote
182 * Octeon. The argument "field" is the member name of the
183 * cvmx_bootmem_named_block_desc to read. Regardless of the type
184 * of the field, the return type is always a u64. The "addr"
185 * parameter is the physical address of the structure.
186 */
187#define CVMX_BOOTMEM_NAMED_GET_FIELD(oct, addr, field) \
188 __cvmx_bootmem_desc_get(oct, addr, \
189 offsetof(struct cvmx_bootmem_named_block_desc, field), \
190 SIZEOF_FIELD(struct cvmx_bootmem_named_block_desc, field))
191
192/**
193 * This function is the implementation of the get macros defined
194 * for individual structure members. The argument are generated
195 * by the macros inorder to read only the needed memory.
196 *
197 * @param oct Pointer to current octeon device
198 * @param base 64bit physical address of the complete structure
199 * @param offset Offset from the beginning of the structure to the member being
200 * accessed.
201 * @param size Size of the structure member.
202 *
203 * @return Value of the structure member promoted into a u64.
204 */
205static inline u64 __cvmx_bootmem_desc_get(struct octeon_device *oct,
206 u64 base,
207 u32 offset,
208 u32 size)
209{
210 base = (1ull << 63) | (base + offset);
211 switch (size) {
212 case 4:
213 return octeon_read_device_mem32(oct, base);
214 case 8:
215 return octeon_read_device_mem64(oct, base);
216 default:
217 return 0;
218 }
219}
220
221/**
222 * This function retrieves the string name of a named block. It is
223 * more complicated than a simple memcpy() since the named block
224 * descriptor may not be directly accessible.
225 *
226 * @param addr Physical address of the named block descriptor
227 * @param str String to receive the named block string name
228 * @param len Length of the string buffer, which must match the length
229 * stored in the bootmem descriptor.
230 */
231static void CVMX_BOOTMEM_NAMED_GET_NAME(struct octeon_device *oct,
232 u64 addr,
233 char *str,
234 u32 len)
235{
236 addr += offsetof(struct cvmx_bootmem_named_block_desc, name);
237 octeon_pci_read_core_mem(oct, addr, str, len);
238 str[len] = 0;
239}
240
241/* See header file for descriptions of functions */
242
243/**
244 * Check the version information on the bootmem descriptor
245 *
246 * @param exact_match
247 * Exact major version to check against. A zero means
248 * check that the version supports named blocks.
249 *
250 * @return Zero if the version is correct. Negative if the version is
251 * incorrect. Failures also cause a message to be displayed.
252 */
253static int __cvmx_bootmem_check_version(struct octeon_device *oct,
254 u32 exact_match)
255{
256 u32 major_version;
257 u32 minor_version;
258
259 if (!oct->bootmem_desc_addr)
260 oct->bootmem_desc_addr =
261 octeon_read_device_mem64(oct,
262 BOOTLOADER_PCI_READ_DESC_ADDR);
263 major_version =
264 (u32)CVMX_BOOTMEM_DESC_GET_FIELD(oct, major_version);
265 minor_version =
266 (u32)CVMX_BOOTMEM_DESC_GET_FIELD(oct, minor_version);
267 dev_dbg(&oct->pci_dev->dev, "%s: major_version=%d\n", __func__,
268 major_version);
269 if ((major_version > 3) ||
270 (exact_match && major_version != exact_match)) {
271 dev_err(&oct->pci_dev->dev, "bootmem ver mismatch %d.%d addr:0x%llx\n",
272 major_version, minor_version,
273 CAST_ULL(oct->bootmem_desc_addr));
274 return -1;
275 } else {
276 return 0;
277 }
278}
279
280static const struct cvmx_bootmem_named_block_desc
281*__cvmx_bootmem_find_named_block_flags(struct octeon_device *oct,
282 const char *name, u32 flags)
283{
284 struct cvmx_bootmem_named_block_desc *desc =
285 &oct->bootmem_named_block_desc;
286 u64 named_addr = cvmx_bootmem_phy_named_block_find(oct, name, flags);
287
288 if (named_addr) {
289 desc->base_addr = CVMX_BOOTMEM_NAMED_GET_FIELD(oct, named_addr,
290 base_addr);
291 desc->size =
292 CVMX_BOOTMEM_NAMED_GET_FIELD(oct, named_addr, size);
293 strncpy(desc->name, name, sizeof(desc->name));
294 desc->name[sizeof(desc->name) - 1] = 0;
295 return &oct->bootmem_named_block_desc;
296 } else {
297 return NULL;
298 }
299}
300
301static u64 cvmx_bootmem_phy_named_block_find(struct octeon_device *oct,
302 const char *name,
303 u32 flags)
304{
305 u64 result = 0;
306
307 __cvmx_bootmem_lock(flags);
308 if (!__cvmx_bootmem_check_version(oct, 3)) {
309 u32 i;
310 u64 named_block_array_addr =
311 CVMX_BOOTMEM_DESC_GET_FIELD(oct,
312 named_block_array_addr);
313 u32 num_blocks = (u32)
314 CVMX_BOOTMEM_DESC_GET_FIELD(oct, nb_num_blocks);
315 u32 name_length = (u32)
316 CVMX_BOOTMEM_DESC_GET_FIELD(oct, named_block_name_len);
317 u64 named_addr = named_block_array_addr;
318
319 for (i = 0; i < num_blocks; i++) {
320 u64 named_size =
321 CVMX_BOOTMEM_NAMED_GET_FIELD(oct, named_addr,
322 size);
323 if (name && named_size) {
324 char *name_tmp =
325 kmalloc(name_length + 1, GFP_KERNEL);
326 CVMX_BOOTMEM_NAMED_GET_NAME(oct, named_addr,
327 name_tmp,
328 name_length);
329 if (!strncmp(name, name_tmp, name_length)) {
330 result = named_addr;
331 kfree(name_tmp);
332 break;
333 }
334 kfree(name_tmp);
335 } else if (!name && !named_size) {
336 result = named_addr;
337 break;
338 }
339
340 named_addr +=
341 sizeof(struct cvmx_bootmem_named_block_desc);
342 }
343 }
344 __cvmx_bootmem_unlock(flags);
345 return result;
346}
347
348/**
349 * Find a named block on the remote Octeon
350 *
351 * @param name Name of block to find
352 * @param base_addr Address the block is at (OUTPUT)
353 * @param size The size of the block (OUTPUT)
354 *
355 * @return Zero on success, One on failure.
356 */
357static int octeon_named_block_find(struct octeon_device *oct, const char *name,
358 u64 *base_addr, u64 *size)
359{
360 const struct cvmx_bootmem_named_block_desc *named_block;
361
362 octeon_remote_lock();
363 named_block = __cvmx_bootmem_find_named_block_flags(oct, name, 0);
364 octeon_remote_unlock();
365 if (named_block) {
366 *base_addr = named_block->base_addr;
367 *size = named_block->size;
368 return 0;
369 }
370 return 1;
371}
372
373static void octeon_remote_lock(void)
374{
375 /* fill this in if any sharing is needed */
376}
377
378static void octeon_remote_unlock(void)
379{
380 /* fill this in if any sharing is needed */
381}
382
383int octeon_console_send_cmd(struct octeon_device *oct, char *cmd_str,
384 u32 wait_hundredths)
385{
386 u32 len = strlen(cmd_str);
387
388 dev_dbg(&oct->pci_dev->dev, "sending \"%s\" to bootloader\n", cmd_str);
389
390 if (len > BOOTLOADER_PCI_WRITE_BUFFER_STR_LEN - 1) {
391 dev_err(&oct->pci_dev->dev, "Command string too long, max length is: %d\n",
392 BOOTLOADER_PCI_WRITE_BUFFER_STR_LEN - 1);
393 return -1;
394 }
395
396 if (octeon_wait_for_bootloader(oct, wait_hundredths) != 0) {
397 dev_err(&oct->pci_dev->dev, "Bootloader not ready for command.\n");
398 return -1;
399 }
400
401 /* Write command to bootloader */
402 octeon_remote_lock();
403 octeon_pci_write_core_mem(oct, BOOTLOADER_PCI_READ_BUFFER_DATA_ADDR,
404 (u8 *)cmd_str, len);
405 octeon_write_device_mem32(oct, BOOTLOADER_PCI_READ_BUFFER_LEN_ADDR,
406 len);
407 octeon_write_device_mem32(oct, BOOTLOADER_PCI_READ_BUFFER_OWNER_ADDR,
408 OCTEON_PCI_IO_BUF_OWNER_OCTEON);
409
410 /* Bootloader should accept command very quickly
411 * if it really was ready
412 */
413 if (octeon_wait_for_bootloader(oct, 200) != 0) {
414 octeon_remote_unlock();
415 dev_err(&oct->pci_dev->dev, "Bootloader did not accept command.\n");
416 return -1;
417 }
418 octeon_remote_unlock();
419 return 0;
420}
421
422int octeon_wait_for_bootloader(struct octeon_device *oct,
423 u32 wait_time_hundredths)
424{
425 dev_dbg(&oct->pci_dev->dev, "waiting %d0 ms for bootloader\n",
426 wait_time_hundredths);
427
428 if (octeon_mem_access_ok(oct))
429 return -1;
430
431 while (wait_time_hundredths > 0 &&
432 octeon_read_device_mem32(oct,
433 BOOTLOADER_PCI_READ_BUFFER_OWNER_ADDR)
434 != OCTEON_PCI_IO_BUF_OWNER_HOST) {
435 if (--wait_time_hundredths <= 0)
436 return -1;
437 schedule_timeout_uninterruptible(HZ / 100);
438 }
439 return 0;
440}
441
442static void octeon_console_handle_result(struct octeon_device *oct,
443 size_t console_num,
444 char *buffer, s32 bytes_read)
445{
446 struct octeon_console *console;
447
448 console = &oct->console[console_num];
449
450 console->waiting = 0;
451}
452
453static char console_buffer[OCTEON_CONSOLE_MAX_READ_BYTES];
454
455static void output_console_line(struct octeon_device *oct,
456 struct octeon_console *console,
457 size_t console_num,
458 char *console_buffer,
459 s32 bytes_read)
460{
461 char *line;
462 s32 i;
463
464 line = console_buffer;
465 for (i = 0; i < bytes_read; i++) {
466 /* Output a line at a time, prefixed */
467 if (console_buffer[i] == '\n') {
468 console_buffer[i] = '\0';
469 if (console->leftover[0]) {
470 dev_info(&oct->pci_dev->dev, "%lu: %s%s\n",
471 console_num, console->leftover,
472 line);
473 console->leftover[0] = '\0';
474 } else {
475 dev_info(&oct->pci_dev->dev, "%lu: %s\n",
476 console_num, line);
477 }
478 line = &console_buffer[i + 1];
479 }
480 }
481
482 /* Save off any leftovers */
483 if (line != &console_buffer[bytes_read]) {
484 console_buffer[bytes_read] = '\0';
485 strcpy(console->leftover, line);
486 }
487}
488
489static void check_console(struct work_struct *work)
490{
491 s32 bytes_read, tries, total_read;
492 struct octeon_console *console;
493 struct cavium_wk *wk = (struct cavium_wk *)work;
494 struct octeon_device *oct = (struct octeon_device *)wk->ctxptr;
495 size_t console_num = wk->ctxul;
496 u32 delay;
497
498 console = &oct->console[console_num];
499 tries = 0;
500 total_read = 0;
501
502 do {
503 /* Take console output regardless of whether it will
504 * be logged
505 */
506 bytes_read =
507 octeon_console_read(oct, console_num, console_buffer,
508 sizeof(console_buffer) - 1, 0);
509 if (bytes_read > 0) {
510 total_read += bytes_read;
511 if (console->waiting) {
512 octeon_console_handle_result(oct, console_num,
513 console_buffer,
514 bytes_read);
515 }
516 if (octeon_console_debug_enabled(console_num)) {
517 output_console_line(oct, console, console_num,
518 console_buffer, bytes_read);
519 }
520 } else if (bytes_read < 0) {
521 dev_err(&oct->pci_dev->dev, "Error reading console %lu, ret=%d\n",
522 console_num, bytes_read);
523 }
524
525 tries++;
526 } while ((bytes_read > 0) && (tries < 16));
527
528 /* If nothing is read after polling the console,
529 * output any leftovers if any
530 */
531 if (octeon_console_debug_enabled(console_num) &&
532 (total_read == 0) && (console->leftover[0])) {
533 dev_info(&oct->pci_dev->dev, "%lu: %s\n",
534 console_num, console->leftover);
535 console->leftover[0] = '\0';
536 }
537
538 delay = OCTEON_CONSOLE_POLL_INTERVAL_MS;
539
540 schedule_delayed_work(&wk->work, msecs_to_jiffies(delay));
541}
542
543int octeon_init_consoles(struct octeon_device *oct)
544{
545 int ret = 0;
546 u64 addr, size;
547
548 ret = octeon_mem_access_ok(oct);
549 if (ret) {
550 dev_err(&oct->pci_dev->dev, "Memory access not okay'\n");
551 return ret;
552 }
553
554 ret = octeon_named_block_find(oct, OCTEON_PCI_CONSOLE_BLOCK_NAME, &addr,
555 &size);
556 if (ret) {
557 dev_err(&oct->pci_dev->dev, "Could not find console '%s'\n",
558 OCTEON_PCI_CONSOLE_BLOCK_NAME);
559 return ret;
560 }
561
562 /* num_consoles > 0, is an indication that the consoles
563 * are accessible
564 */
565 oct->num_consoles = octeon_read_device_mem32(oct,
566 addr + offsetof(struct octeon_pci_console_desc,
567 num_consoles));
568 oct->console_desc_addr = addr;
569
570 dev_dbg(&oct->pci_dev->dev, "Initialized consoles. %d available\n",
571 oct->num_consoles);
572
573 return ret;
574}
575
576int octeon_add_console(struct octeon_device *oct, u32 console_num)
577{
578 int ret = 0;
579 u32 delay;
580 u64 coreaddr;
581 struct delayed_work *work;
582 struct octeon_console *console;
583
584 if (console_num >= oct->num_consoles) {
585 dev_err(&oct->pci_dev->dev,
586 "trying to read from console number %d when only 0 to %d exist\n",
587 console_num, oct->num_consoles);
588 } else {
589 console = &oct->console[console_num];
590
591 console->waiting = 0;
592
593 coreaddr = oct->console_desc_addr + console_num * 8 +
594 offsetof(struct octeon_pci_console_desc,
595 console_addr_array);
596 console->addr = octeon_read_device_mem64(oct, coreaddr);
597 coreaddr = console->addr + offsetof(struct octeon_pci_console,
598 buf_size);
599 console->buffer_size = octeon_read_device_mem32(oct, coreaddr);
600 coreaddr = console->addr + offsetof(struct octeon_pci_console,
601 input_base_addr);
602 console->input_base_addr =
603 octeon_read_device_mem64(oct, coreaddr);
604 coreaddr = console->addr + offsetof(struct octeon_pci_console,
605 output_base_addr);
606 console->output_base_addr =
607 octeon_read_device_mem64(oct, coreaddr);
608 console->leftover[0] = '\0';
609
610 work = &oct->console_poll_work[console_num].work;
611
612 INIT_DELAYED_WORK(work, check_console);
613 oct->console_poll_work[console_num].ctxptr = (void *)oct;
614 oct->console_poll_work[console_num].ctxul = console_num;
615 delay = OCTEON_CONSOLE_POLL_INTERVAL_MS;
616 schedule_delayed_work(work, msecs_to_jiffies(delay));
617
618 if (octeon_console_debug_enabled(console_num)) {
619 ret = octeon_console_send_cmd(oct,
620 "setenv pci_console_active 1",
621 2000);
622 }
623
624 console->active = 1;
625 }
626
627 return ret;
628}
629
630/**
631 * Removes all consoles
632 *
633 * @param oct octeon device
634 */
635void octeon_remove_consoles(struct octeon_device *oct)
636{
637 u32 i;
638 struct octeon_console *console;
639
640 for (i = 0; i < oct->num_consoles; i++) {
641 console = &oct->console[i];
642
643 if (!console->active)
644 continue;
645
646 cancel_delayed_work_sync(&oct->console_poll_work[i].
647 work);
648 console->addr = 0;
649 console->buffer_size = 0;
650 console->input_base_addr = 0;
651 console->output_base_addr = 0;
652 }
653
654 oct->num_consoles = 0;
655}
656
657static inline int octeon_console_free_bytes(u32 buffer_size,
658 u32 wr_idx,
659 u32 rd_idx)
660{
661 if (rd_idx >= buffer_size || wr_idx >= buffer_size)
662 return -1;
663
664 return ((buffer_size - 1) - (wr_idx - rd_idx)) % buffer_size;
665}
666
667static inline int octeon_console_avail_bytes(u32 buffer_size,
668 u32 wr_idx,
669 u32 rd_idx)
670{
671 if (rd_idx >= buffer_size || wr_idx >= buffer_size)
672 return -1;
673
674 return buffer_size - 1 -
675 octeon_console_free_bytes(buffer_size, wr_idx, rd_idx);
676}
677
678int octeon_console_read(struct octeon_device *oct, u32 console_num,
679 char *buffer, u32 buf_size, u32 flags)
680{
681 int bytes_to_read;
682 u32 rd_idx, wr_idx;
683 struct octeon_console *console;
684
685 if (console_num >= oct->num_consoles) {
686 dev_err(&oct->pci_dev->dev, "Attempted to read from disabled console %d\n",
687 console_num);
688 return 0;
689 }
690
691 console = &oct->console[console_num];
692
693 /* Check to see if any data is available.
694 * Maybe optimize this with 64-bit read.
695 */
696 rd_idx = octeon_read_device_mem32(oct, console->addr +
697 offsetof(struct octeon_pci_console, output_read_index));
698 wr_idx = octeon_read_device_mem32(oct, console->addr +
699 offsetof(struct octeon_pci_console, output_write_index));
700
701 bytes_to_read = octeon_console_avail_bytes(console->buffer_size,
702 wr_idx, rd_idx);
703 if (bytes_to_read <= 0)
704 return bytes_to_read;
705
706 bytes_to_read = MIN(bytes_to_read, (s32)buf_size);
707
708 /* Check to see if what we want to read is not contiguous, and limit
709 * ourselves to the contiguous block
710 */
711 if (rd_idx + bytes_to_read >= console->buffer_size)
712 bytes_to_read = console->buffer_size - rd_idx;
713
714 octeon_pci_read_core_mem(oct, console->output_base_addr + rd_idx,
715 buffer, bytes_to_read);
716 octeon_write_device_mem32(oct, console->addr +
717 offsetof(struct octeon_pci_console,
718 output_read_index),
719 (rd_idx + bytes_to_read) %
720 console->buffer_size);
721
722 return bytes_to_read;
723}