Remove alpha direct I/O access, use RTC instead: http://marc.info/?l=util-linux-ng&m=141682406902804 Resolves the alpha 2020 issue for util-linux: http://marc.info/?l=util-linux-ng&m=148387021519787 Now it is only the kernel's RTC problem. * sys-utils/hwclock.c: remove alpha cmos * sys-utils/hwclock-cmos.c: same * sys-utils/hwclock.h: same * sys-utils/hwclock.8.in: same Signed-off-by: J William Piggott <elseifthen@xxxxxxx> --- sys-utils/hwclock-cmos.c | 316 ++++++----------------------------------------- sys-utils/hwclock.8.in | 110 +++++------------ sys-utils/hwclock.c | 32 ----- sys-utils/hwclock.h | 9 -- 4 files changed, 72 insertions(+), 395 deletions(-) diff --git a/sys-utils/hwclock-cmos.c b/sys-utils/hwclock-cmos.c index 4915471..7a9d595 100644 --- a/sys-utils/hwclock-cmos.c +++ b/sys-utils/hwclock-cmos.c @@ -76,17 +76,8 @@ static int inb(int c __attribute__((__unused__))) return 0; } # endif /* __i386__ __x86_64__ */ -#elif defined(__alpha__) -# ifdef HAVE_SYS_IO_H -# include <sys/io.h> -# else -/* <asm/io.h> fails to compile, probably because of u8 etc */ -extern unsigned int inb(unsigned long port); -extern void outb(unsigned char b, unsigned long port); -extern int iopl(int level); -# endif -#else /* __alpha__ */ -# warning "disable cmos access - not i386, x86_64, or alpha" +#else +# warning "disable cmos access - not i386 or x86_64" static void outb(int a __attribute__((__unused__)), int b __attribute__((__unused__))) { @@ -106,201 +97,18 @@ static int inb(int c __attribute__((__unused__))) #define IOPL_NOT_IMPLEMENTED -2 /* - * The epoch. - * - * Unix uses 1900 as epoch for a struct tm, and 1970 for a time_t. But what - * was written to CMOS? - * - * Digital DECstations use 1928 - this is on a mips or alpha Digital Unix - * uses 1952, e.g. on AXPpxi33. Windows NT uses 1980. The ARC console - * expects to boot Windows NT and uses 1980. (But a Ruffian uses 1900, just - * like SRM.) It is reported that ALPHA_PRE_V1_2_SRM_CONSOLE uses 1958. + * POSIX uses 1900 as epoch for a struct tm, and 1970 for a time_t. */ #define TM_EPOCH 1900 -static int cmos_epoch = 1900; -/* - * Martin Ostermann writes: - * - * The problem with the Jensen is twofold: First, it has the clock at a - * different address. Secondly, it has a distinction between "local" and - * normal bus addresses. The local ones pertain to the hardware integrated - * into the chipset, like serial/parallel ports and of course, the RTC. - * Those need to be addressed differently. This is handled fine in the - * kernel, and it's not a problem, since this usually gets totally optimized - * by the compile. But the i/o routines of (g)libc lack this support so far. - * The result of this is, that the old clock program worked only on the - * Jensen when USE_DEV_PORT was defined, but not with the normal inb/outb - * functions. - */ -static int use_dev_port = 0; /* 1 for Jensen */ -static int dev_port_fd; -static unsigned short clock_ctl_addr = 0x70; /* 0x170 for Jensen */ -static unsigned short clock_data_addr = 0x71; /* 0x171 for Jensen */ +static unsigned short clock_ctl_addr = 0x70; +static unsigned short clock_data_addr = 0x71; static int century_byte = 0; /* 0: don't access a century byte * 50 (0x32): usual PC value * 55 (0x37): PS/2 */ -#ifdef __alpha__ -static int funkyTOY = 0; /* 1 for PC164/LX164/SX164 type alpha */ -#endif - -#ifdef __alpha - -static int is_in_cpuinfo(char *fmt, char *str) -{ - FILE *cpuinfo; - char field[256]; - char format[sizeof(field)]; - int found = 0; - - sprintf(format, "%s : %s", fmt, "%255s"); - - cpuinfo = fopen(_PATH_PROC_CPUINFO, "r"); - if (cpuinfo) { - do { - if (fscanf(cpuinfo, format, field) == 1) { - if (strncmp(field, str, strlen(str)) == 0) - found = 1; - break; - } - } while (fgets(field, 256, cpuinfo)); - fclose(cpuinfo); - } - return found; -} - -/* - * Set cmos_epoch, either from user options, or by asking the kernel, or by - * looking at /proc/cpu_info - */ -void set_cmos_epoch(const struct hwclock_control *ctl) -{ - unsigned long epoch; - - /* Believe the user */ - if (ctl->epoch_option) { - cmos_epoch = ctl->epoch_option; - return; - } - - if (ctl->ARCconsole) - cmos_epoch = 1980; - - if (ctl->ARCconsole || ctl->SRM) - return; - -#ifdef __linux__ - /* - * If we can ask the kernel, we don't need guessing from - * /proc/cpuinfo - */ - if (get_epoch_rtc(ctl, &epoch, 1) == 0) { - cmos_epoch = epoch; - return; - } -#endif - - /* - * The kernel source today says: read the year. - * - * If it is in 0-19 then the epoch is 2000. - * If it is in 20-47 then the epoch is 1980. - * If it is in 48-69 then the epoch is 1952. - * If it is in 70-99 then the epoch is 1928. - * - * Otherwise the epoch is 1900. - * TODO: Clearly, this must be changed before 2019. - */ - /* - * See whether we are dealing with SRM or MILO, as they have - * different "epoch" ideas. - */ - if (is_in_cpuinfo("system serial number", "MILO")) { - if (ctl->debug) - printf(_("booted from MILO\n")); - /* - * See whether we are dealing with a RUFFIAN aka Alpha PC-164 - * UX (or BX), as they have REALLY different TOY (TimeOfYear) - * format: BCD, and not an ARC-style epoch. BCD is detected - * dynamically, but we must NOT adjust like ARC. - */ - if (is_in_cpuinfo("system type", "Ruffian")) { - if (debug) - printf(_("Ruffian BCD clock\n")); - return; - } - } - - cmos_epoch = 1980; -} - -void set_cmos_access(const struct hwclock_control *ctl) -{ - - /* - * See whether we're dealing with a Jensen---it has a weird I/O - * system. DEC was just learning how to build Alpha PCs. - */ - if (ctl->Jensen || is_in_cpuinfo("system type", "Jensen")) { - use_dev_port = 1; - clock_ctl_addr = 0x170; - clock_data_addr = 0x171; - if (ctl->debug) - printf(_("clockport adjusted to 0x%x\n"), - clock_ctl_addr); - } - - /* - * See whether we are dealing with PC164/LX164/SX164, as they have a - * TOY that must be accessed differently to work correctly. - */ - /* Nautilus stuff reported by Neoklis Kyriazis */ - if (ctl->funky_toy || - is_in_cpuinfo("system variation", "PC164") || - is_in_cpuinfo("system variation", "LX164") || - is_in_cpuinfo("system variation", "SX164") || - is_in_cpuinfo("system type", "Nautilus")) { - funkyTOY = 1; - if (ctl->debug) - printf(_("funky TOY!\n")); - } -} -#endif /* __alpha */ - -#ifdef __alpha__ -/* - * The Alpha doesn't allow user-level code to disable interrupts (for good - * reasons). Instead, we ensure atomic operation by performing the operation - * and checking whether the high 32 bits of the cycle counter changed. If - * they did, a context switch must have occurred and we redo the operation. - * As long as the operation is reasonably short, it will complete - * atomically, eventually. - */ -static unsigned long -atomic(const char *name, - unsigned long (*op) (const struct hwclock_control *ctl, unsigned long), - const struct hwclock_control *ctl, - unsigned long arg) -{ - unsigned long ts1, ts2, n, v; - - for (n = 0; n < 1000; ++n) { - asm volatile ("rpcc %0":"r=" (ts1)); - v = (*op) (ctl, arg); - asm volatile ("rpcc %0":"r=" (ts2)); - - if ((ts1 ^ ts2) >> 32 == 0) { - return v; - } - } - errx(EXIT_FAILURE, _("atomic %s failed for 1000 iterations!"), - name); -} -#else - /* * Hmmh, this isn't very atomic. Maybe we should force an error instead? * @@ -315,68 +123,37 @@ atomic(const char *name __attribute__ ((__unused__)), return (*op) (ctl, arg); } -#endif +/* + * We only want to read CMOS data, but unfortunately writing to bit 7 + * disables (1) or enables (0) NMI; since this bit is read-only we have + * to guess the old status. Various docs suggest that one should disable + * NMI while reading/writing CMOS data, and enable it again afterwards. + * This would yield the sequence + * + * outb (reg | 0x80, 0x70); + * val = inb(0x71); + * outb (0x0d, 0x70); // 0x0d: random read-only location + * + * Other docs state that "any write to 0x70 should be followed by an + * action to 0x71 or the RTC will be left in an unknown state". Most + * docs say that it doesn't matter at all what one does. + * + * bit 0x80: disable NMI while reading - should we? Let us follow the + * kernel and not disable. Called only with 0 <= reg < 128 + */ static inline unsigned long cmos_read(const struct hwclock_control *ctl, unsigned long reg) { - if (use_dev_port) { - unsigned char v = reg | 0x80; - lseek(dev_port_fd, clock_ctl_addr, 0); - if (write(dev_port_fd, &v, 1) == -1 && ctl->debug) - warn(_("cmos_read(): write to control address %X failed"), - clock_ctl_addr); - lseek(dev_port_fd, clock_data_addr, 0); - if (read(dev_port_fd, &v, 1) == -1 && ctl->debug) - warn(_("cmos_read(): read from data address %X failed"), - clock_data_addr); - return v; - } else { - /* - * We only want to read CMOS data, but unfortunately writing - * to bit 7 disables (1) or enables (0) NMI; since this bit - * is read-only we have to guess the old status. Various - * docs suggest that one should disable NMI while - * reading/writing CMOS data, and enable it again - * afterwards. This would yield the sequence - * - * outb (reg | 0x80, 0x70); - * val = inb(0x71); - * outb (0x0d, 0x70); // 0x0d: random read-only location - * - * Other docs state that "any write to 0x70 should be - * followed by an action to 0x71 or the RTC will be left in - * an unknown state". Most docs say that it doesn't matter at - * all what one does. - */ - /* - * bit 0x80: disable NMI while reading - should we? Let us - * follow the kernel and not disable. Called only with 0 <= - * reg < 128 - */ - outb(reg, clock_ctl_addr); - return inb(clock_data_addr); - } + outb(reg, clock_ctl_addr); + return inb(clock_data_addr); } static inline unsigned long cmos_write(const struct hwclock_control *ctl, unsigned long reg, unsigned long val) { - if (use_dev_port) { - unsigned char v = reg | 0x80; - lseek(dev_port_fd, clock_ctl_addr, 0); - if (write(dev_port_fd, &v, 1) == -1 && ctl->debug) - warn(_("cmos_write(): write to control address %X failed"), - clock_ctl_addr); - v = (val & 0xff); - lseek(dev_port_fd, clock_data_addr, 0); - if (write(dev_port_fd, &v, 1) == -1 && ctl->debug) - warn(_("cmos_write(): write to data address %X failed"), - clock_data_addr); - } else { - outb(reg, clock_ctl_addr); - outb(val, clock_data_addr); - } + outb(reg, clock_ctl_addr); + outb(val, clock_data_addr); return 0; } @@ -409,9 +186,7 @@ static unsigned long cmos_set_time(const struct hwclock_control *ctl, save_freq_select = cmos_read(ctl, 10); /* stop and reset prescaler */ cmos_write(ctl, 10, (save_freq_select | 0x70)); - tm.tm_year += TM_EPOCH; - century = tm.tm_year / 100; - tm.tm_year -= cmos_epoch; + century = (tm.tm_year + TM_EPOCH) / 100; tm.tm_year %= 100; tm.tm_mon += 1; tm.tm_wday += 1; @@ -475,10 +250,6 @@ static void hclock_set_time(const struct hwclock_control *ctl, const struct tm * static inline int cmos_clock_busy(const struct hwclock_control *ctl) { return -#ifdef __alpha__ - /* poll bit 4 (UF) of Control Register C */ - funkyTOY ? (hclock_read(ctl, 12) & 0x10) : -#endif /* poll bit 7 (UIP) of Control Register A */ (hclock_read(ctl, 10) & 0x80); } @@ -594,7 +365,6 @@ static int read_hardware_clock_cmos(const struct hwclock_control *ctl */ tm->tm_wday -= 1; tm->tm_mon -= 1; - tm->tm_year += (cmos_epoch - TM_EPOCH); if (tm->tm_year < 69) tm->tm_year += 100; if (pmbit) { @@ -616,7 +386,7 @@ static int set_hardware_clock_cmos(const struct hwclock_control *ctl return 0; } -#if defined(__i386__) || defined(__alpha__) || defined(__x86_64__) +#if defined(__i386__) || defined(__x86_64__) # if defined(HAVE_IOPL) static int i386_iopl(const int level) { @@ -640,23 +410,15 @@ static int get_permissions_cmos(void) { int rc; - if (use_dev_port) { - if ((dev_port_fd = open(_PATH_DEV_PORT, O_RDWR)) < 0) { - warn(_("cannot open %s"), _PATH_DEV_PORT); - rc = 1; - } else - rc = 0; - } else { - rc = i386_iopl(3); - if (rc == IOPL_NOT_IMPLEMENTED) { - warnx(_("I failed to get permission because I didn't try.")); - } else if (rc != 0) { - rc = errno; - warn(_("unable to get I/O port access: " - "the iopl(3) call failed")); - if (rc == EPERM && geteuid()) - warnx(_("Probably you need root privileges.\n")); - } + rc = i386_iopl(3); + if (rc == IOPL_NOT_IMPLEMENTED) { + warnx(_("I failed to get permission because I didn't try.")); + } else if (rc != 0) { + rc = errno; + warn(_("unable to get I/O port access: " + "the iopl(3) call failed")); + if (rc == EPERM && geteuid()) + warnx(_("Probably you need root privileges.\n")); } return rc ? 1 : 0; } @@ -676,7 +438,7 @@ static struct clock_ops cmos_interface = { struct clock_ops *probe_for_cmos_clock(void) { static const int have_cmos = -#if defined(__i386__) || defined(__alpha__) || defined(__x86_64__) +#if defined(__i386__) || defined(__x86_64__) TRUE; #else FALSE; diff --git a/sys-utils/hwclock.8.in b/sys-utils/hwclock.8.in index d1e8027..80a579f 100644 --- a/sys-utils/hwclock.8.in +++ b/sys-utils/hwclock.8.in @@ -44,22 +44,30 @@ discussion below, under .B \-\-getepoch .TQ .B \-\-setepoch -These functions are for Alpha machines only. +These functions are for Alpha machines only, and are only available +through the Linux kernel RTC driver. .sp -Read and set the kernel's Hardware Clock epoch value. +They are used to read and set the kernel's Hardware Clock epoch value. Epoch is the number of years into AD to which a zero year value in the -Hardware Clock refers. For example, if you are using the convention -that the year counter in your Hardware Clock contains the number of -full years since 1952, then the kernel's Hardware Clock epoch value -must be 1952. +Hardware Clock refers. For example, if the machine's BIOS sets the year +counter in the Hardware Clock to contain the number of full years since +1952, then the kernel's Hardware Clock epoch value must be 1952. .sp The \fB\%\-\-setepoch\fR function requires using the .B \%\-\-epoch -option to specify the year. -.sp +option to specify the year. For example: +.RS +.IP "" 4 +.B hwclock\ \-\-setepoch\ \-\-epoch=1952 +.PP +The RTC driver attempts to guess the correct epoch value, so setting it +may not be required. +.PP This epoch value is used whenever .B \%hwclock -reads or sets the Hardware Clock. +reads or sets the Hardware Clock on an Alpha machine. For ISA machines +the kernel uses the fixed Hardware Clock epoch of 1900. +.RE . .TP .B \-\-predict @@ -278,23 +286,27 @@ can help you understand how the program works. . .TP .B \-\-directisa -This option is meaningful for: ISA compatible machines including x86, and -x86_64; and Alpha (which has a similar Hardware Clock interface). For other -machines, it has no effect. This option tells +This option is meaningful for ISA compatible machines in the x86 and +x86_64 family. For other machines, it has no effect. This option tells .B \%hwclock to use explicit I/O instructions to access the Hardware Clock. Without this option, .B \%hwclock -will use the rtc device, which it assumes to be driven by the RTC device -driver. As of v2.26 it will no longer automatically use directisa when -the rtc driver is unavailable; this was causing an unsafe condition that -could allow two processes to access the Hardware Clock at the same time. -Direct hardware access from userspace should only be used for testing, -troubleshooting, and as a last resort when all other methods fail. See -the +will use the rtc device file, which it assumes to be driven by the Linux +RTC device driver. As of v2.26 it will no longer automatically use +directisa when the rtc driver is unavailable; this was causing an unsafe +condition that could allow two processes to access the Hardware Clock at +the same time. Direct hardware access from userspace should only be +used for testing, troubleshooting, and as a last resort when all other +methods fail. See the .BR \-\-rtc " option." . .TP +.BI \-\-epoch= year +This option is required when using the +.BR \%\-\-setepoch \ function. +. +.TP .BR \-f , \ \-\-rtc=\fIfilename\fR .RB "Override " \%hwclock 's default rtc device file name. Otherwise it will @@ -402,55 +414,6 @@ option to be used. See the discussion below, under .BR "The Adjust Function" . .RE . -.SH OPTIONS FOR ALPHA MACHINES ONLY -. -.TP -.B \-\-arc -This option is equivalent to -.B \%\-\-epoch=1980 -and is used to specify the most common epoch on Alphas -with an ARC console (although Ruffians have an epoch of 1900). -. -.TP -.BI \-\-epoch= year -Specifies the year which is the beginning of the Hardware Clock's epoch, -that is the number of years into AD to which a zero value in the -Hardware Clock's year counter refers. It is used together with the -.B \%\-\-setepoch -option to set the kernel's idea of the epoch of the Hardware Clock. -.sp -For example, on a Digital Unix machine: -.RS -.IP "" 4 -.B hwclock\ \-\-setepoch\ \-\-epoch=1952 -.RE -. -.TP -.B \-\-funky\-toy -.TQ -.B \-\-jensen -These two options specify what kind of Alpha machine you have. They -are invalid if you do not have an Alpha and are usually unnecessary -if you do; -.B \%hwclock -should be able to determine what it is running on when -.I \%/proc -is mounted. -.sp -.RB "The " \%\-\-jensen -option is used for Jensen models; -.B \%\-\-funky\-toy -means that the machine requires the UF bit instead of the UIP bit in -the Hardware Clock to detect a time transition. The "toy" in the option -name refers to the Time Of Year facility of the machine. -. -.TP -.B \-\-srm -This option is equivalent to -.B \%\-\-epoch=1900 -and is used to specify the most common epoch on Alphas -with an SRM console. -. .SH NOTES . .SS Clocks in a Linux System @@ -566,15 +529,8 @@ reasons that userspace programs are generally not supposed to do direct I/O and disable interrupts. .B \%hwclock provides it for testing, troubleshooting, and because it may be the -only method available on ISA compatible and Alpha systems which do not -have a working rtc device driver. -.PP -In the case of a Jensen Alpha, there is no way for -.B \%hwclock -to execute those I/O instructions, and so it uses instead the -.I \%/dev/port -device special file, which provides almost as low-level an interface to -the I/O subsystem. +only method available on ISA systems which do not have a working rtc +device driver. .PP On an m68k system, .B \%hwclock diff --git a/sys-utils/hwclock.c b/sys-utils/hwclock.c index bd2a057..8914f94 100644 --- a/sys-utils/hwclock.c +++ b/sys-utils/hwclock.c @@ -1279,11 +1279,6 @@ static void usage(const struct hwclock_control *ctl, const char *fmt, ...) " the default is %1$s\n"), _PATH_ADJTIME); fputs(_(" --test do not update anything, just show what would happen\n" " -D, --debug debugging mode\n" "\n"), usageto); -#ifdef __alpha__ - fputs(_(" -J|--jensen, -A|--arc, -S|--srm, -F|--funky-toy\n" - " tell hwclock the type of Alpha you have (see hwclock(8))\n" - "\n"), usageto); -#endif if (fmt) { va_start(ap, fmt); @@ -1344,15 +1339,6 @@ int main(int argc, char **argv) { "version", no_argument, NULL, 'v' }, { "systohc", no_argument, NULL, 'w' }, { "debug", no_argument, NULL, 'D' }, -#ifdef __alpha__ - { "ARC", no_argument, NULL, 'A' }, - { "arc", no_argument, NULL, 'A' }, - { "Jensen", no_argument, NULL, 'J' }, - { "jensen", no_argument, NULL, 'J' }, - { "SRM", no_argument, NULL, 'S' }, - { "srm", no_argument, NULL, 'S' }, - { "funky-toy", no_argument, NULL, 'F' }, -#endif { "set", no_argument, NULL, OPT_SET }, #ifdef __linux__ { "getepoch", no_argument, NULL, OPT_GETEPOCH }, @@ -1438,20 +1424,6 @@ int main(int argc, char **argv) case 'w': ctl.systohc = 1; break; -#ifdef __alpha__ - case 'A': - ctl.ARCconsole = 1; - break; - case 'J': - ctl.Jensen = 1; - break; - case 'S': - ctl.SRM = 1; - break; - case 'F': - ctl.funky_toy = 1; - break; -#endif case OPT_SET: ctl.set = 1; break; @@ -1538,10 +1510,6 @@ int main(int argc, char **argv) "either --utc or --localtime")); hwclock_exit(&ctl, EX_USAGE); } -#ifdef __alpha__ - set_cmos_epoch(&ctl); - set_cmos_access(&ctl); -#endif if (ctl.set || ctl.predict) { if (parse_date(&when, ctl.date_opt, NULL)) diff --git a/sys-utils/hwclock.h b/sys-utils/hwclock.h index 383b970..f090ed7 100644 --- a/sys-utils/hwclock.h +++ b/sys-utils/hwclock.h @@ -32,12 +32,6 @@ struct hwclock_control { hctosys:1, utc:1, systohc:1, -#ifdef __alpha__ - ARCconsole:1, - Jensen:1, - SRM:1, - funky_toy:1, -#endif #ifdef __linux__ getepoch:1, setepoch:1, @@ -71,9 +65,6 @@ typedef int bool; extern int debug; extern unsigned long epoch_option; extern double time_diff(struct timeval subtrahend, struct timeval subtractor); -/* cmos.c */ -extern void set_cmos_epoch(const struct hwclock_control *ctl); -extern void set_cmos_access(const struct hwclock_control *ctl); /* rtc.c */ extern int get_epoch_rtc(const struct hwclock_control *ctl, unsigned long *epoch, int silent); -- To unsubscribe from this list: send the line "unsubscribe util-linux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
