^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * drivers/base/power/trace.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2006 Linus Torvalds
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Trace facility for suspend/resume problems, when none of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * devices may be working.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #define pr_fmt(fmt) "PM: " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/pm-trace.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/rtc.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/suspend.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/mc146818rtc.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include "power.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) * Horrid, horrid, horrid.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) * It turns out that the _only_ piece of hardware that actually
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) * keeps its value across a hard boot (and, more importantly, the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) * POST init sequence) is literally the realtime clock.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) * Never mind that an RTC chip has 114 bytes (and often a whole
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * other bank of an additional 128 bytes) of nice SRAM that is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * _designed_ to keep data - the POST will clear it. So we literally
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * can just use the few bytes of actual time data, which means that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) * we're really limited.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) * It means, for example, that we can't use the seconds at all
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) * (since the time between the hang and the boot might be more
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) * than a minute), and we'd better not depend on the low bits of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) * the minutes either.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) * There are the wday fields etc, but I wouldn't guarantee those
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) * are dependable either. And if the date isn't valid, either the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) * hw or POST will do strange things.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) * So we're left with:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) * - year: 0-99
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) * - month: 0-11
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) * - day-of-month: 1-28
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) * - hour: 0-23
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) * - min: (0-30)*2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) * Giving us a total range of 0-16128000 (0xf61800), ie less
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) * than 24 bits of actual data we can save across reboots.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) * And if your box can't boot in less than three minutes,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) * you're screwed.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) * Now, almost 24 bits of data is pitifully small, so we need
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) * to be pretty dense if we want to use it for anything nice.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) * What we do is that instead of saving off nice readable info,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) * we save off _hashes_ of information that we can hopefully
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) * regenerate after the reboot.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) * In particular, this means that we might be unlucky, and hit
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) * a case where we have a hash collision, and we end up not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) * being able to tell for certain exactly which case happened.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) * But that's hopefully unlikely.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) * What we do is to take the bits we can fit, and split them
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) * into three parts (16*997*1009 = 16095568), and use the values
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) * for:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) * - 0-15: user-settable
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) * - 0-996: file + line number
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) * - 0-1008: device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) #define USERHASH (16)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) #define FILEHASH (997)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) #define DEVHASH (1009)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) #define DEVSEED (7919)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) bool pm_trace_rtc_abused __read_mostly;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) EXPORT_SYMBOL_GPL(pm_trace_rtc_abused);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) static unsigned int dev_hash_value;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) static int set_magic_time(unsigned int user, unsigned int file, unsigned int device)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) unsigned int n = user + USERHASH*(file + FILEHASH*device);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) // June 7th, 2006
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) static struct rtc_time time = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) .tm_sec = 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) .tm_min = 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) .tm_hour = 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) .tm_mday = 7,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) .tm_mon = 5, // June - counting from zero
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) .tm_year = 106,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) .tm_wday = 3,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) .tm_yday = 160,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) .tm_isdst = 1
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) time.tm_year = (n % 100);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) n /= 100;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) time.tm_mon = (n % 12);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) n /= 12;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) time.tm_mday = (n % 28) + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) n /= 28;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) time.tm_hour = (n % 24);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) n /= 24;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) time.tm_min = (n % 20) * 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) n /= 20;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) mc146818_set_time(&time);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) pm_trace_rtc_abused = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) return n ? -1 : 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) static unsigned int read_magic_time(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) struct rtc_time time;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) unsigned int val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) mc146818_get_time(&time);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) pr_info("RTC time: %ptRt, date: %ptRd\n", &time, &time);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) val = time.tm_year; /* 100 years */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) if (val > 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) val -= 100;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) val += time.tm_mon * 100; /* 12 months */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) val += (time.tm_mday-1) * 100 * 12; /* 28 month-days */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) val += time.tm_hour * 100 * 12 * 28; /* 24 hours */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) val += (time.tm_min / 3) * 100 * 12 * 28 * 24; /* 20 3-minute intervals */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) return val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) * This is just the sdbm hash function with a user-supplied
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) * seed and final size parameter.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) static unsigned int hash_string(unsigned int seed, const char *data, unsigned int mod)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) unsigned char c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) while ((c = *data++) != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) seed = (seed << 16) + (seed << 6) - seed + c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) return seed % mod;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) void set_trace_device(struct device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) dev_hash_value = hash_string(DEVSEED, dev_name(dev), DEVHASH);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) EXPORT_SYMBOL(set_trace_device);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) * We could just take the "tracedata" index into the .tracedata
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) * section instead. Generating a hash of the data gives us a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) * chance to work across kernel versions, and perhaps more
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) * importantly it also gives us valid/invalid check (ie we will
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) * likely not give totally bogus reports - if the hash matches,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) * it's not any guarantee, but it's a high _likelihood_ that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) * the match is valid).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) void generate_pm_trace(const void *tracedata, unsigned int user)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) unsigned short lineno = *(unsigned short *)tracedata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) const char *file = *(const char **)(tracedata + 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) unsigned int user_hash_value, file_hash_value;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) if (!x86_platform.legacy.rtc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) user_hash_value = user % USERHASH;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) file_hash_value = hash_string(lineno, file, FILEHASH);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) set_magic_time(user_hash_value, file_hash_value, dev_hash_value);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) EXPORT_SYMBOL(generate_pm_trace);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) extern char __tracedata_start[], __tracedata_end[];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) static int show_file_hash(unsigned int value)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) int match;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) char *tracedata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) match = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) for (tracedata = __tracedata_start ; tracedata < __tracedata_end ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) tracedata += 2 + sizeof(unsigned long)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) unsigned short lineno = *(unsigned short *)tracedata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) const char *file = *(const char **)(tracedata + 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) unsigned int hash = hash_string(lineno, file, FILEHASH);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) if (hash != value)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) pr_info(" hash matches %s:%u\n", file, lineno);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) match++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) return match;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) static int show_dev_hash(unsigned int value)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) int match = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) struct list_head *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) device_pm_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) entry = dpm_list.prev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) while (entry != &dpm_list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) struct device * dev = to_device(entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) unsigned int hash = hash_string(DEVSEED, dev_name(dev), DEVHASH);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) if (hash == value) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) dev_info(dev, "hash matches\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) match++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) entry = entry->prev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) device_pm_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) return match;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) static unsigned int hash_value_early_read;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) int show_trace_dev_match(char *buf, size_t size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) unsigned int value = hash_value_early_read / (USERHASH * FILEHASH);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) struct list_head *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) * It's possible that multiple devices will match the hash and we can't
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) * tell which is the culprit, so it's best to output them all.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) device_pm_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) entry = dpm_list.prev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) while (size && entry != &dpm_list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) struct device *dev = to_device(entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) unsigned int hash = hash_string(DEVSEED, dev_name(dev),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) DEVHASH);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) if (hash == value) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) int len = snprintf(buf, size, "%s\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) dev_driver_string(dev));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) if (len > size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) len = size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) buf += len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) ret += len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) size -= len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) entry = entry->prev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) device_pm_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) static int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) pm_trace_notify(struct notifier_block *nb, unsigned long mode, void *_unused)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) switch (mode) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) case PM_POST_HIBERNATION:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) case PM_POST_SUSPEND:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) if (pm_trace_rtc_abused) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) pm_trace_rtc_abused = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) pr_warn("Possible incorrect RTC due to pm_trace, please use 'ntpdate' or 'rdate' to reset it.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) static struct notifier_block pm_trace_nb = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) .notifier_call = pm_trace_notify,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) static int __init early_resume_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) if (!x86_platform.legacy.rtc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) hash_value_early_read = read_magic_time();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) register_pm_notifier(&pm_trace_nb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) static int __init late_resume_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) unsigned int val = hash_value_early_read;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) unsigned int user, file, dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) if (!x86_platform.legacy.rtc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) user = val % USERHASH;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) val = val / USERHASH;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) file = val % FILEHASH;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) val = val / FILEHASH;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) dev = val /* % DEVHASH */;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) pr_info(" Magic number: %d:%d:%d\n", user, file, dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) show_file_hash(file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) show_dev_hash(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) core_initcall(early_resume_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) late_initcall(late_resume_init);
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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