blob: 0b852c5f653768349e4b7561b30e7d6e13f2cd6d [file] [log] [blame]
Andrew Jeffery4fe996c2018-02-27 12:16:48 +10301// SPDX-License-Identifier: Apache-2.0
2// Copyright (C) 2018 IBM Corp.
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +11003
4#define _GNU_SOURCE
5#include <assert.h>
6#include <errno.h>
7#include <fcntl.h>
8#include <getopt.h>
9#include <limits.h>
10#include <poll.h>
11#include <stdbool.h>
12#include <stdint.h>
13#include <stdio.h>
14#include <stdlib.h>
15#include <string.h>
16#include <syslog.h>
17#include <signal.h>
18#include <sys/ioctl.h>
19#include <sys/mman.h>
20#include <sys/stat.h>
21#include <sys/timerfd.h>
22#include <sys/types.h>
23#include <time.h>
24#include <unistd.h>
25#include <inttypes.h>
26#include <mtd/mtd-abi.h>
27
Andrew Jeffery26558db2018-08-10 00:22:38 +093028#include "mboxd.h"
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +110029#include "common.h"
Andrew Jeffery457a6e52018-08-08 11:21:08 +093030#include "transport_mbox.h"
Andrew Jefferyf593b1b2018-08-08 11:01:04 +093031#include "windows.h"
Andrew Jefferyeebc6bd2018-08-08 10:38:19 +093032#include "flash.h"
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +110033
34/* Initialisation Functions */
35
36/*
37 * init_window_state() - Initialise a new window to a known state
38 * @window: The window to initialise
39 * @size: The size of the window
40 */
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +100041static void init_window_state(struct window_context *window, uint32_t size)
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +110042{
43 window->mem = NULL;
44 window->flash_offset = FLASH_OFFSET_UNINIT;
45 window->size = size;
46 window->dirty_bmap = NULL;
47 window->age = 0;
48}
49
50/*
51 * init_window_mem() - Divide the reserved memory region among the windows
52 * @context: The mbox context pointer
53 *
54 * Return: 0 on success otherwise negative error code
55 */
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +100056static int init_window_mem(struct mbox_context *context)
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +110057{
58 void *mem_location = context->mem;
59 int i;
60
61 /*
62 * Carve up the reserved memory region and allocate it to each of the
63 * windows. The windows are placed one after the other in ascending
64 * order, so the first window will be first in memory and so on. We
65 * shouldn't have allocated more windows than we have memory, but if we
66 * did we will error out here
67 */
68 for (i = 0; i < context->windows.num; i++) {
Suraj Jitindar Singh28519592017-04-27 14:48:58 +100069 uint32_t size = context->windows.window[i].size;
70 MSG_DBG("Window %d @ %p for size 0x%.8x\n", i,
71 mem_location, size);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +110072 context->windows.window[i].mem = mem_location;
Suraj Jitindar Singh28519592017-04-27 14:48:58 +100073 mem_location += size;
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +110074 if (mem_location > (context->mem + context->mem_size)) {
75 /* Tried to allocate window past the end of memory */
76 MSG_ERR("Total size of windows exceeds reserved mem\n");
77 MSG_ERR("Try smaller or fewer windows\n");
78 MSG_ERR("Mem size: 0x%.8x\n", context->mem_size);
79 return -1;
80 }
81 }
82
83 return 0;
84}
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +100085/*
Andrew Jefferyc1a67fa2018-08-08 17:07:38 +093086 * windows_init() - Initalise the window cache
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +100087 * @context: The mbox context pointer
88 *
89 * Return: 0 on success otherwise negative
90 */
Andrew Jefferyc1a67fa2018-08-08 17:07:38 +093091int windows_init(struct mbox_context *context)
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +100092{
93 int i;
94
95 /* Check if window size and number set - otherwise set to default */
96 if (!context->windows.default_size) {
97 /* Default to 1MB windows */
98 context->windows.default_size = 1 << 20;
99 }
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000100 MSG_INFO("Window size: 0x%.8x\n", context->windows.default_size);
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +1000101 if (!context->windows.num) {
102 /* Use the entire reserved memory region by default */
103 context->windows.num = context->mem_size /
104 context->windows.default_size;
105 }
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000106 MSG_INFO("Number of windows: %d\n", context->windows.num);
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +1000107
108 context->windows.window = calloc(context->windows.num,
109 sizeof(*context->windows.window));
110 if (!context->windows.window) {
111 MSG_ERR("Memory allocation failed\n");
112 return -1;
113 }
114
115 for (i = 0; i < context->windows.num; i++) {
116 init_window_state(&context->windows.window[i],
117 context->windows.default_size);
118 }
119
120 return init_window_mem(context);
121}
122
123/*
Andrew Jefferyf5f51422018-08-08 17:08:33 +0930124 * windows_free() - Free the window cache
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +1000125 * @context: The mbox context pointer
126 */
Andrew Jefferyf5f51422018-08-08 17:08:33 +0930127void windows_free(struct mbox_context *context)
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +1000128{
129 int i;
130
131 /* Check window cache has actually been allocated */
132 if (context->windows.window) {
133 for (i = 0; i < context->windows.num; i++) {
134 free(context->windows.window[i].dirty_bmap);
135 }
136 free(context->windows.window);
137 }
138}
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100139
140/* Write from Window Functions */
141
142/*
Andrew Jeffery3200c072018-08-08 17:12:03 +0930143 * window_flush_v1() - Handle writing when erase and block size differ
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100144 * @context: The mbox context pointer
145 * @offset_bytes: The offset in the current window to write from (bytes)
146 * @count_bytes: Number of bytes to write
147 *
Andrew Jeffery3200c072018-08-08 17:12:03 +0930148 * Handle a window_flush for dirty memory when block_size is less than the
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100149 * flash erase size
150 * This requires us to be a bit careful because we might have to erase more
151 * than we want to write which could result in data loss if we don't have the
152 * entire portion of flash to be erased already saved in memory (for us to
153 * write back after the erase)
154 *
155 * Return: 0 on success otherwise negative error code
156 */
Andrew Jeffery3200c072018-08-08 17:12:03 +0930157int window_flush_v1(struct mbox_context *context,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100158 uint32_t offset_bytes, uint32_t count_bytes)
159{
160 int rc;
161 uint32_t flash_offset;
162 struct window_context low_mem = { 0 }, high_mem = { 0 };
163
164 /* Find where in phys flash this is based on the window.flash_offset */
165 flash_offset = context->current->flash_offset + offset_bytes;
166
167 /*
168 * low_mem.flash_offset = erase boundary below where we're writing
169 * low_mem.size = size from low_mem.flash_offset to where we're writing
170 *
171 * high_mem.flash_offset = end of where we're writing
172 * high_mem.size = size from end of where we're writing to next erase
173 * boundary
174 */
175 low_mem.flash_offset = align_down(flash_offset,
176 context->mtd_info.erasesize);
177 low_mem.size = flash_offset - low_mem.flash_offset;
178 high_mem.flash_offset = flash_offset + count_bytes;
179 high_mem.size = align_up(high_mem.flash_offset,
180 context->mtd_info.erasesize) -
181 high_mem.flash_offset;
182
183 /*
184 * Check if we already have a copy of the required flash areas in
185 * memory as part of the existing window
186 */
187 if (low_mem.flash_offset < context->current->flash_offset) {
188 /* Before the start of our current window */
189 low_mem.mem = malloc(low_mem.size);
190 if (!low_mem.mem) {
191 MSG_ERR("Unable to allocate memory\n");
Andrew Jeffery8eab2152018-08-09 23:47:29 +0930192 return -ENOMEM;
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100193 }
Andrew Jefferye0cdd3e2018-08-08 16:51:44 +0930194 rc = flash_copy(context, low_mem.flash_offset,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100195 low_mem.mem, low_mem.size);
196 if (rc < 0) {
197 goto out;
198 }
199 }
200 if ((high_mem.flash_offset + high_mem.size) >
201 (context->current->flash_offset + context->current->size)) {
202 /* After the end of our current window */
203 high_mem.mem = malloc(high_mem.size);
204 if (!high_mem.mem) {
205 MSG_ERR("Unable to allocate memory\n");
Andrew Jeffery8eab2152018-08-09 23:47:29 +0930206 rc = -ENOMEM;
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100207 goto out;
208 }
Andrew Jefferye0cdd3e2018-08-08 16:51:44 +0930209 rc = flash_copy(context, high_mem.flash_offset,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100210 high_mem.mem, high_mem.size);
211 if (rc < 0) {
212 goto out;
213 }
214 }
215
216 /*
217 * We need to erase the flash from low_mem.flash_offset->
218 * high_mem.flash_offset + high_mem.size
219 */
Andrew Jeffery4f5d29c2018-08-08 16:58:04 +0930220 rc = flash_erase(context, low_mem.flash_offset,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100221 (high_mem.flash_offset - low_mem.flash_offset) +
222 high_mem.size);
223 if (rc < 0) {
224 MSG_ERR("Couldn't erase flash\n");
225 goto out;
226 }
227
228 /* Write back over the erased area */
229 if (low_mem.mem) {
230 /* Exceed window at the start */
Andrew Jeffery0293f2f2018-08-08 16:59:45 +0930231 rc = flash_write(context, low_mem.flash_offset, low_mem.mem,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100232 low_mem.size);
233 if (rc < 0) {
234 goto out;
235 }
236 }
Andrew Jeffery0293f2f2018-08-08 16:59:45 +0930237 rc = flash_write(context, flash_offset,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100238 context->current->mem + offset_bytes, count_bytes);
239 if (rc < 0) {
240 goto out;
241 }
242 /*
243 * We still need to write the last little bit that we erased - it's
244 * either in the current window or the high_mem window.
245 */
246 if (high_mem.mem) {
247 /* Exceed window at the end */
Andrew Jeffery0293f2f2018-08-08 16:59:45 +0930248 rc = flash_write(context, high_mem.flash_offset, high_mem.mem,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100249 high_mem.size);
250 if (rc < 0) {
251 goto out;
252 }
253 } else {
254 /* Write from the current window - it's atleast that big */
Andrew Jeffery0293f2f2018-08-08 16:59:45 +0930255 rc = flash_write(context, high_mem.flash_offset,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100256 context->current->mem + offset_bytes +
257 count_bytes, high_mem.size);
258 if (rc < 0) {
259 goto out;
260 }
261 }
262
263out:
264 free(low_mem.mem);
265 free(high_mem.mem);
266 return rc;
267}
268
269/*
Andrew Jeffery3200c072018-08-08 17:12:03 +0930270 * window_flush() - Write back to the flash from the current window
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100271 * @context: The mbox context pointer
272 * @offset_bytes: The offset in the current window to write from (blocks)
273 * @count_bytes: Number of blocks to write
274 * @type: Whether this is an erase & write or just an erase
275 *
276 * Return: 0 on success otherwise negative error code
277 */
Andrew Jeffery3200c072018-08-08 17:12:03 +0930278int window_flush(struct mbox_context *context, uint32_t offset,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100279 uint32_t count, uint8_t type)
280{
281 int rc;
282 uint32_t flash_offset, count_bytes = count << context->block_size_shift;
283 uint32_t offset_bytes = offset << context->block_size_shift;
284
285 switch (type) {
286 case WINDOW_ERASED: /* >= V2 ONLY -> block_size == erasesize */
287 flash_offset = context->current->flash_offset + offset_bytes;
Andrew Jeffery4f5d29c2018-08-08 16:58:04 +0930288 rc = flash_erase(context, flash_offset, count_bytes);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100289 if (rc < 0) {
290 MSG_ERR("Couldn't erase flash\n");
291 return rc;
292 }
293 break;
294 case WINDOW_DIRTY:
295 /*
296 * For protocol V1, block_size may be smaller than erase size
297 * so we have a special function to make sure that we do this
298 * correctly without losing data.
299 */
300 if (log_2(context->mtd_info.erasesize) !=
301 context->block_size_shift) {
Andrew Jeffery3200c072018-08-08 17:12:03 +0930302 return window_flush_v1(context, offset_bytes,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100303 count_bytes);
304 }
305 flash_offset = context->current->flash_offset + offset_bytes;
306
307 /* Erase the flash */
Andrew Jeffery4f5d29c2018-08-08 16:58:04 +0930308 rc = flash_erase(context, flash_offset, count_bytes);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100309 if (rc < 0) {
310 return rc;
311 }
312
313 /* Write to the erased flash */
Andrew Jeffery0293f2f2018-08-08 16:59:45 +0930314 rc = flash_write(context, flash_offset,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100315 context->current->mem + offset_bytes,
316 count_bytes);
317 if (rc < 0) {
318 return rc;
319 }
320
321 break;
322 default:
323 /* We shouldn't be able to get here */
324 MSG_ERR("Write from window with invalid type: %d\n", type);
Andrew Jeffery8eab2152018-08-09 23:47:29 +0930325 return -EPERM;
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100326 }
327
328 return 0;
329}
330
331/* Window Management Functions */
332
333/*
Andrew Jeffery348ea792018-08-08 17:13:53 +0930334 * windows_alloc_dirty_bytemap() - (re)allocate all the window dirty bytemaps
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100335 * @context: The mbox context pointer
336 */
Andrew Jeffery348ea792018-08-08 17:13:53 +0930337void windows_alloc_dirty_bytemap(struct mbox_context *context)
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100338{
339 struct window_context *cur;
340 int i;
341
342 for (i = 0; i < context->windows.num; i++) {
343 cur = &context->windows.window[i];
344 /* There may already be one allocated */
345 free(cur->dirty_bmap);
346 /* Allocate the new one */
Andrew Jeffery41c337e2018-08-13 23:30:16 +0930347 cur->dirty_bmap = calloc((context->windows.default_size >>
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100348 context->block_size_shift),
349 sizeof(*cur->dirty_bmap));
350 }
351}
352
353/*
Andrew Jeffery7d5ada62018-08-08 17:16:16 +0930354 * window_set_bytemap() - Set the window bytemap
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100355 * @context: The mbox context pointer
356 * @cur: The window to set the bytemap of
357 * @offset: Where in the window to set the bytemap (blocks)
358 * @size: The number of blocks to set
359 * @val: The value to set the bytemap to
360 *
361 * Return: 0 on success otherwise negative error code
362 */
Andrew Jeffery7d5ada62018-08-08 17:16:16 +0930363int window_set_bytemap(struct mbox_context *context, struct window_context *cur,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100364 uint32_t offset, uint32_t size, uint8_t val)
365{
366 if (offset + size > (cur->size >> context->block_size_shift)) {
367 MSG_ERR("Tried to set window bytemap past end of window\n");
368 MSG_ERR("Requested offset: 0x%x size: 0x%x window size: 0x%x\n",
369 offset << context->block_size_shift,
370 size << context->block_size_shift,
371 cur->size << context->block_size_shift);
Andrew Jeffery6a0e2de2018-08-07 22:31:00 +0930372 return -EACCES;
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100373 }
374
375 memset(cur->dirty_bmap + offset, val, size);
376 return 0;
377}
378
379/*
Andrew Jefferyb65bb4c2018-08-08 17:18:24 +0930380 * windows_close_current() - Close the current (active) window
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100381 * @context: The mbox context pointer
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100382 * @flags: Flags as defined for a close command in the protocol
383 *
384 * This closes the current window. If the host has requested the current window
385 * be closed then we don't need to set the bmc event bit
386 * (set_bmc_event == false), otherwise if the current window has been closed
387 * without the host requesting it the bmc event bit must be set to indicate this
388 * to the host (set_bmc_event == true).
389 */
Andrew Jeffery2ebfd202018-08-20 11:46:28 +0930390void windows_close_current(struct mbox_context *context, uint8_t flags)
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100391{
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000392 MSG_DBG("Close current window, flags: 0x%.2x\n", flags);
393
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100394 if (flags & FLAGS_SHORT_LIFETIME) {
395 context->current->age = 0;
396 }
397
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100398 context->current = NULL;
399 context->current_is_write = false;
400}
401
402/*
Andrew Jeffery5dc9f952018-08-08 17:21:34 +0930403 * window_reset() - Reset a window context to a well defined default state
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100404 * @context: The mbox context pointer
405 * @window: The window to reset
406 */
Andrew Jeffery5dc9f952018-08-08 17:21:34 +0930407void window_reset(struct mbox_context *context, struct window_context *window)
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100408{
409 window->flash_offset = FLASH_OFFSET_UNINIT;
410 window->size = context->windows.default_size;
411 if (window->dirty_bmap) { /* Might not have been allocated */
Andrew Jeffery7d5ada62018-08-08 17:16:16 +0930412 window_set_bytemap(context, window, 0,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100413 window->size >> context->block_size_shift,
414 WINDOW_CLEAN);
415 }
416 window->age = 0;
417}
418
419/*
Andrew Jefferyd6a74262018-08-08 17:25:01 +0930420 * windows_reset_all() - Reset all windows to a well defined default state
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100421 * @context: The mbox context pointer
Andrew Jeffery2ebfd202018-08-20 11:46:28 +0930422 *
423 * @return True if there was a window open that was closed, false otherwise
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100424 */
Andrew Jeffery2ebfd202018-08-20 11:46:28 +0930425bool windows_reset_all(struct mbox_context *context)
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100426{
Andrew Jeffery2ebfd202018-08-20 11:46:28 +0930427 bool closed = context->current;
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100428 int i;
429
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000430 MSG_DBG("Resetting all windows\n");
Andrew Jeffery2ebfd202018-08-20 11:46:28 +0930431
432 context->windows.max_age = 0;
433
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100434 /* We might have an open window which needs closing */
Andrew Jeffery2ebfd202018-08-20 11:46:28 +0930435
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100436 if (context->current) {
Andrew Jeffery2ebfd202018-08-20 11:46:28 +0930437 windows_close_current(context, FLAGS_NONE);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100438 }
Andrew Jeffery2ebfd202018-08-20 11:46:28 +0930439
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100440 for (i = 0; i < context->windows.num; i++) {
Andrew Jeffery5dc9f952018-08-08 17:21:34 +0930441 window_reset(context, &context->windows.window[i]);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100442 }
443
Andrew Jeffery2ebfd202018-08-20 11:46:28 +0930444 return closed;
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100445}
446
447/*
Andrew Jeffery9412f052018-08-08 17:25:47 +0930448 * windows_find_oldest() - Find the oldest (Least Recently Used) window
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100449 * @context: The mbox context pointer
450 *
451 * Return: Pointer to the least recently used window
452 */
Andrew Jeffery9412f052018-08-08 17:25:47 +0930453struct window_context *windows_find_oldest(struct mbox_context *context)
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100454{
455 struct window_context *oldest = NULL, *cur;
456 uint32_t min_age = context->windows.max_age + 1;
457 int i;
458
459 for (i = 0; i < context->windows.num; i++) {
460 cur = &context->windows.window[i];
461
462 if (cur->age < min_age) {
463 min_age = cur->age;
464 oldest = cur;
465 }
466 }
467
468 return oldest;
469}
470
471/*
Andrew Jefferyd8c12e12018-08-08 17:26:31 +0930472 * windows_find_largest() - Find the largest window in the window cache
Suraj Jitindar Singh5a3a0662017-04-27 11:55:26 +1000473 * @context: The mbox context pointer
474 *
475 * Return: The largest window
476 */
Andrew Jefferyd8c12e12018-08-08 17:26:31 +0930477struct window_context *windows_find_largest(struct mbox_context *context)
Suraj Jitindar Singh5a3a0662017-04-27 11:55:26 +1000478{
479 struct window_context *largest = NULL, *cur;
480 uint32_t max_size = 0;
481 int i;
482
483 for (i = 0; i < context->windows.num; i++) {
484 cur = &context->windows.window[i];
485
486 if (cur->size > max_size) {
487 max_size = cur->size;
488 largest = cur;
489 }
490 }
491
492 return largest;
493}
494
495/*
Andrew Jeffery17c477a2018-08-08 17:27:19 +0930496 * windows_search() - Search the window cache for a window containing offset
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100497 * @context: The mbox context pointer
498 * @offset: Absolute flash offset to search for (bytes)
499 * @exact: If the window must exactly map the requested offset
500 *
501 * This will search the cache of windows for one containing the requested
502 * offset. For V1 of the protocol windows must exactly map the offset since we
503 * can't tell the host how much of its request we actually mapped and it will
504 * thus assume it can access window->size from the offset we give it.
505 *
506 * Return: Pointer to a window containing the requested offset otherwise
507 * NULL
508 */
Andrew Jeffery17c477a2018-08-08 17:27:19 +0930509struct window_context *windows_search(struct mbox_context *context,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100510 uint32_t offset, bool exact)
511{
512 struct window_context *cur;
513 int i;
514
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000515 MSG_DBG("Searching for window which contains 0x%.8x %s\n",
516 offset, exact ? "exactly" : "");
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100517 for (i = 0; i < context->windows.num; i++) {
518 cur = &context->windows.window[i];
519 if (cur->flash_offset == FLASH_OFFSET_UNINIT) {
520 /* Uninitialised Window */
521 if (offset == FLASH_OFFSET_UNINIT) {
522 return cur;
523 }
524 continue;
525 }
526 if ((offset >= cur->flash_offset) &&
527 (offset < (cur->flash_offset + cur->size))) {
528 if (exact && (cur->flash_offset != offset)) {
529 continue;
530 }
531 /* This window contains the requested offset */
532 cur->age = ++(context->windows.max_age);
533 return cur;
534 }
535 }
536
537 return NULL;
538}
539
540/*
Andrew Jefferyebbfce52018-08-08 17:29:45 +0930541 * windows_create_map() - Create a window mapping which maps the requested offset
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100542 * @context: The mbox context pointer
543 * @this_window: A pointer to update to the "new" window
544 * @offset: Absolute flash offset to create a mapping for (bytes)
545 * @exact: If the window must exactly map the requested offset
546 *
547 * This is used to create a window mapping for the requested offset when there
548 * is no existing window in the cache which satisfies the offset. This involves
549 * choosing an existing window from the window cache to evict so we can use it
550 * to store the flash contents from the requested offset, we then point the
551 * caller to that window since it now maps their request.
552 *
553 * Return: 0 on success otherwise negative error code
554 */
Andrew Jefferyebbfce52018-08-08 17:29:45 +0930555int windows_create_map(struct mbox_context *context,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100556 struct window_context **this_window, uint32_t offset,
557 bool exact)
558{
559 struct window_context *cur = NULL;
560 int rc;
561
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000562 MSG_DBG("Creating window which maps 0x%.8x %s\n", offset,
563 exact ? "exactly" : "");
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100564
565 /* Search for an uninitialised window, use this before evicting */
Andrew Jeffery17c477a2018-08-08 17:27:19 +0930566 cur = windows_search(context, FLASH_OFFSET_UNINIT, true);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100567
568 /* No uninitialised window found, we need to choose one to "evict" */
569 if (!cur) {
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000570 MSG_DBG("No uninitialised window, evicting one\n");
Andrew Jeffery9412f052018-08-08 17:25:47 +0930571 cur = windows_find_oldest(context);
Andrew Jeffery5dc9f952018-08-08 17:21:34 +0930572 window_reset(context, cur);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100573 }
574
Deepak Kodihalliaee73892017-07-12 13:18:06 -0500575/*
576 * In case of the virtual pnor, as of now it's possible that a window may
577 * have content less than it's max size. We basically copy one flash partition
578 * per window, and some partitions are smaller than the max size. An offset
579 * right after such a small partition ends should lead to new mapping. The code
580 * below prevents that.
581 */
582#ifndef VIRTUAL_PNOR_ENABLED
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100583 if (!exact) {
584 /*
585 * It would be nice to align the offsets which we map to window
586 * size, this will help prevent overlap which would be an
587 * inefficient use of our reserved memory area (we would like
588 * to "cache" as much of the acutal flash as possible in
589 * memory). If we're protocol V1 however we must ensure the
590 * offset requested is exactly mapped.
591 */
592 offset &= ~(cur->size - 1);
593 }
Deepak Kodihalliaee73892017-07-12 13:18:06 -0500594#endif
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100595
Andrew Jeffery3da0de62018-03-23 12:27:15 +1030596 if (offset > context->flash_size) {
597 MSG_ERR("Tried to open read window past flash limit\n");
Andrew Jeffery8eab2152018-08-09 23:47:29 +0930598 return -EINVAL;
Andrew Jeffery3da0de62018-03-23 12:27:15 +1030599 } else if ((offset + cur->size) > context->flash_size) {
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100600 /*
601 * There is V1 skiboot implementations out there which don't
602 * mask offset with window size, meaning when we have
603 * window size == flash size we will never allow the host to
604 * open a window except at 0x0, which isn't always where the
605 * host requests it. Thus we have to ignore this check and just
606 * hope the host doesn't access past the end of the window
607 * (which it shouldn't) for V1 implementations to get around
608 * this.
609 */
610 if (context->version == API_VERSION_1) {
611 cur->size = align_down(context->flash_size - offset,
612 1 << context->block_size_shift);
613 } else {
Andrew Jeffery3da0de62018-03-23 12:27:15 +1030614 /*
615 * Allow requests to exceed the flash size, but limit
616 * the response to the size of the flash.
617 */
618 cur->size = context->flash_size - offset;
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100619 }
620 }
621
622 /* Copy from flash into the window buffer */
Andrew Jefferye0cdd3e2018-08-08 16:51:44 +0930623 rc = flash_copy(context, offset, cur->mem, cur->size);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100624 if (rc < 0) {
625 /* We don't know how much we've copied -> better reset window */
Andrew Jeffery5dc9f952018-08-08 17:21:34 +0930626 window_reset(context, cur);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100627 return rc;
628 }
Andrew Jeffery1a3f8432018-03-02 10:18:02 +1030629 /*
630 * rc isn't guaranteed to be aligned, so align up
631 *
632 * FIXME: This should only be the case for the vpnor ToC now, so handle
633 * it there
634 */
Suraj Jitindar Singh8493c332017-10-06 14:29:45 +1100635 cur->size = align_up(rc, (1ULL << context->block_size_shift));
636 /* Would like a known value, pick 0xFF to it looks like erased flash */
637 memset(cur->mem + rc, 0xFF, cur->size - rc);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100638
639 /*
640 * Since for V1 windows aren't constrained to start at multiples of
641 * window size it's possible that something already maps this offset.
642 * Reset any windows which map this offset to avoid coherency problems.
643 * We just have to check for anything which maps the start or the end
644 * of the window since all windows are the same size so another window
645 * cannot map just the middle of this window.
646 */
647 if (context->version == API_VERSION_1) {
648 uint32_t i;
649
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000650 MSG_DBG("Checking for window overlap\n");
651
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100652 for (i = offset; i < (offset + cur->size); i += (cur->size - 1)) {
653 struct window_context *tmp = NULL;
654 do {
Andrew Jeffery17c477a2018-08-08 17:27:19 +0930655 tmp = windows_search(context, i, false);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100656 if (tmp) {
Andrew Jeffery5dc9f952018-08-08 17:21:34 +0930657 window_reset(context, tmp);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100658 }
659 } while (tmp);
660 }
661 }
662
663 /* Clear the bytemap of the window just loaded -> we know it's clean */
Andrew Jeffery7d5ada62018-08-08 17:16:16 +0930664 window_set_bytemap(context, cur, 0,
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100665 cur->size >> context->block_size_shift,
666 WINDOW_CLEAN);
667
668 /* Update so we know what's in the window */
669 cur->flash_offset = offset;
670 cur->age = ++(context->windows.max_age);
671 *this_window = cur;
672
673 return 0;
674}