Commit Graph

8 Commits

Author SHA1 Message Date
Feng Tang 57e6319dd6 vrtc: change its year offset from 1960 to 1972
Real world year equals the value in vrtc YEAR register plus an offset.
We used 1960 as the offset to make leap year consistent, but for a
device's first use, its YEAR register is 0 and the system year will
be parsed as 1960 which is not a valid UNIX time and will cause many
applications to fail mysteriously. So we use 1972 instead to fix this
issue.

Updated patch which adds a sanity check suggested by Mathias

This isn't a change in behaviour for systems, because 1972 is the one we
actually use. It's the old version in upstream which is out of sync with
all devices.

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-11 23:58:58 -02:00
Paul Gortmaker 69c60c88ee x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULE
These files were implicitly getting EXPORT_SYMBOL via device.h
which was including module.h, but that will be fixed up shortly.

By fixing these now, we can avoid seeing things like:

arch/x86/kernel/rtc.c:29: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’
arch/x86/kernel/pci-dma.c:20: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’
arch/x86/kernel/e820.c:69: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL_GPL’

[ with input from Randy Dunlap <rdunlap@xenotime.net> and also
  from Stephen Rothwell <sfr@canb.auug.org.au> ]

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:35 -04:00
Matt Fleming 47997d756a x86/rtc: Don't recursively acquire rtc_lock
A deadlock was introduced on x86 in commit ef68c8f87e ("x86:
Serialize EFI time accesses on rtc_lock") because efi_get_time()
and friends can be called with rtc_lock already held by
read_persistent_time(), e.g.:

 timekeeping_init()
    read_persistent_clock()     <-- acquire rtc_lock
        efi_get_time()
            phys_efi_get_time() <-- acquire rtc_lock <DEADLOCK>

To fix this let's push the locking down into the get_wallclock()
and set_wallclock() implementations.  Only the clock
implementations that access the x86 RTC directly need to acquire
rtc_lock, so it makes sense to push the locking down into the
rtc, vrtc and efi code.

The virtualization implementations don't require rtc_lock to be
held because they provide their own serialization.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Acked-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Avi Kivity <avi@redhat.com> [for the virtualization aspect]
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-21 16:16:09 +02:00
Feng Tang 09552b2696 x86/mrst/vrtc: Fix boot crash in mrst_rtc_init()
The sfi_mrtc_array[] only gets initialized when the sfi mrtc
table is parsed, so the vrtc_paddr should be initalized after it
too.

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1302140389-27603-1-git-send-email-feng.tang@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-07 11:27:42 +02:00
Feng Tang 168202c7bf mrst/vrtc: Avoid using cmos rtc ops
If we don't assign Moorestown specific wallclock init and ops function
the rtc/persisent clock code will use cmos rtc for access, this will
crash Moorestown in that the ioports are not present.

Also in vrtc driver, should avoid using cmos access to check UIP status.

[feng.tang@intel.com: use set_fixmap_offset_nocache() to simplify code]
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-14 18:20:43 +01:00
Vasiliy Kulikov 5ca9afdb9f x86, mrst: Check platform_device_register() return code
platform_device_register() may fail, if so propagate the return
code from mrst_device_create().

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
LKML-Reference: <1290104207-31279-1-git-send-email-segoon@openwall.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-11-18 13:45:46 -08:00
Feng Tang 0146f26145 rtc: Add drivers/rtc/rtc-mrst.c
Provide the standard kernel rtc driver interface on top of the vrtc layer
added in the previous patch.

Signed-off-by: Feng Tang <feng.tang@intel.com>
LKML-Reference: <20101110172911.3311.20593.stgit@localhost.localdomain>
[Fixed swapped arguments on IPC]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
[Cleaned up and the device creation moved to arch/x86/platform]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-11-11 11:34:27 +01:00
Feng Tang 7309282c90 x86: mrst: Add vrtc driver which serves as a wall clock device
Moorestown platform doesn't have a m146818 RTC device like traditional
x86 PC, but a firmware emulated virtual RTC device(vrtc), which provides
some basic RTC functions like get/set time. vrtc serves as the only
wall clock device on Moorestown platform.

[ tglx: Changed the exports to _GPL ]

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
LKML-Reference: <20101110172837.3311.40483.stgit@localhost.localdomain>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-11-11 11:34:27 +01:00