Commit Graph

73947 Commits

Author SHA1 Message Date
Mike Frysinger b5f87aa41d Blackfin arch: cleanup BF54x header file and add BF547 definition
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-21 16:04:49 +08:00
Mike Frysinger 7160e9503a Blackfin arch: fix building for BF542 processors which only have 1 TWI
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-21 16:03:07 +08:00
Mike Frysinger 8d6c242062 Blackfin arch: rename _return_from_exception to _bfin_return_from_exception and export it
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-21 15:53:49 +08:00
Mike Frysinger d0025e5edf Blackfin arch: move EXPORT_SYMBOL() to C files where the symbol is actually defined
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-21 15:34:51 +08:00
Sonic Zhang e40540b304 Blackfin arch: fix bug NOR Flash MTD mount fail
Config EBIU flash mode properly. EBIU_MODE EBIU_FCTL
EBIU_MBSCTL register should be configurd to Flash
mode.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-21 23:49:52 +08:00
Cliff Cai 28a44d4bd6 Blackfin arch: export symbol get_dma_curr_desc_ptr for driver usage
Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-21 15:22:58 +08:00
Robin Getz 90c7f4686f Blackfin arch: cleanup kernel exception message, don't insult the customer.
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-18 00:35:33 +08:00
Bernd Schmidt af8a5af3ff Blackfin arch: fix bug kernel not to boot up with mtd filesystems
Revert this patch:
move the init sections to the end of memory, so that after they
are free, run time memory is all continugous - this should help decrease
memory fragementation. When doing this, we also pack some of the other
sections a little closer together, to make sure we don't waste memory.
To make this happen, we need to rename the .data.init_task section to
.init_task.data, so it doesn't get picked up by the linker script glob.

Since it causes the kernel not to boot up with mtd filesystems.

Signed-off-by: Bernd Schmidt <bernd.schmidt@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-18 00:09:49 +08:00
Jie Zhang a961d65963 Blackfin arch: More explicitly describe what the instructions do in inline assembly.
Signed-off-by: Jie Zhang <jie.zhang@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-18 00:00:10 +08:00
Michael Hennerich 561cc18b86 Blackfin arch: add AXIS AX88180 Gigabit Ethernet Hardware and Driver to board files
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-17 23:56:08 +08:00
Robin Getz 4c26c6c9bf Blackfin arch: print out modules that are loaded if we get a kernel oops
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-18 00:20:49 +08:00
Michael Hennerich 5c91fb902d Blackfin arch: Add assembly function insl_16
/*
 * CPUs often take a performance hit when accessing unaligned memory
 * locations. The actual performance hit varies, it can be small if the
 * hardware handles it or large if we have to take an exception and fix
 * it
 * in software.
 *
 * Since an ethernet header is 14 bytes network drivers often end up
 * with
 * the IP header at an unaligned offset. The IP header can be aligned by
 * shifting the start of the packet by 2 bytes. Drivers should do this
 * with:
 *
 * skb_reserve(NET_IP_ALIGN);
 *
 * The downside to this alignment of the IP header is that the DMA is
 * now
 * unaligned. On some architectures the cost of an unaligned DMA is high
 * and this cost outweighs the gains made by aligning the IP header.
 *
 * Since this trade off varies between architectures, we allow
 * NET_IP_ALIGN
 * to be overridden.
 */

This new function insl_16 allows to read form 32-bit IO and writes to
16-bit aligned memory. This is useful in above described scenario -
In particular with the AXIS AX88180 Gigabit Ethernet MAC.
Once the device is in 32-bit mode, reads from the RX FIFO always
decrements 4bytes.
While on the other side the destination address in SDRAM is always
16-bit aligned.
If we use skb_reserve(0) the receive buffer is 32-bit aligned but later
we hit a unaligned exception in the IP code.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-17 23:46:58 +08:00
Mike Frysinger 1754a5d9f9 Blackfin arch: use do_div() for the 64bit division as pointed out by Bernd
If you need a 64 bit divide in the kernel, use asm/div64.h.
Revert the addition of udivdi3.

Cc: Bernd Schmidt <bernd.schmidt@analog.com>
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-23 11:28:11 +08:00
Mike Frysinger e709d84b99 Blackfin arch: fix spurious newline in header
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-17 23:24:07 +08:00
Adrian Bunk 8d2e24c3c1 Blackfin arch: unexport get_wchan
The only user of get_wchan I was able to find is the proc fs - and proc
can't be built modular.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-17 23:05:06 +08:00
Adrian Bunk 05c484355f Blackfin arch: remove dump_thread()
The only user is the a.out support.

It was therefore removed prior to the blackfin merge from all
architectures not supporting a.out.

Currently, Blackfin doesn't suppport a.out.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-18 00:41:56 +08:00
Robert P. J. Day 09db9487b0 Blackfin arch: Typo: "CONFIG_RTC_BFIN_MODULE" -> "CONFIG_RTC_DRV_BFIN_MODULE"
i'm *reasonably* confident that this is a typo that should be fixed.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-17 22:57:03 +08:00
Michael Hennerich c7d4896621 Blackfin arch: Dont use cs_change_per_word, since the AD7877 driver doesnt require it anymore; fix bus numbers, fix typos
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 21:33:31 +08:00
Mike Frysinger f02bcec598 Blackfin arch: relocate linux/usb_isp1362.h to linux/usb/isp1362.h like in newer linux trees
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 21:29:15 +08:00
Mike Frysinger 632f658b36 Blackfin arch: the usb_sl811.h header has been moved to usb/sl811.h so lets use that version now
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 21:25:47 +08:00
Mike Frysinger 70b63ba739 Blackfin arch: do not include linux/autoconf.h
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 21:22:53 +08:00
Mike Frysinger 9862cc5278 Blackfin arch: change get_bf537_ether_addr() to bfin_get_ether_addr() since this is not BF537 specific and to better match other Blackfin-specific conventions
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 21:21:20 +08:00
Mike Frysinger 137b1529da Blackfin arch: sharing the board-specific MAC function does not make sense so move it into board-specific files
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-22 16:07:03 +08:00
Mike Frysinger b33d518777 Blackfin arch: fix double fault definition for BF561 core A and core B
VDSP has double fault on core a/b inverted for BF561 -- bit 11 is core a while bit 12 is core b

Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 21:15:47 +08:00
Mike Frysinger a055b2b4de Blackfin arch: remove useless CONFIG_IRQCHIP_DEMUX_GPIO
since we have this always turned on now and dont want it off (and hasnt been an option in a while)

Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 21:12:32 +08:00
Mike Frysinger 0feea17f94 Blackfin arch: fix missing newline to file
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 21:10:42 +08:00
Mike Frysinger 7c7fd17017 Blackfin arch: add BF547 to list of accepted procs
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 21:10:21 +08:00
Robin Getz 839e01c2bf Blackfin arch: move the init sections to the end of memory to help decrease memory fragementation
move the init sections to the end of memory, so that after they
are free, run time memory is all continugous - this should help decrease
memory fragementation. When doing this, we also pack some of the other
sections a little closer together, to make sure we don't waste memory.
To make this happen, we need to rename the .data.init_task section to
.init_task.data, so it doesn't get picked up by the linker script glob.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 20:57:53 +08:00
Mike Frysinger 74ce8322bf Blackfin arch: split debug stuff off into Kconfig.debug like everyone else
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-21 23:50:49 +08:00
Mike Frysinger 529a73fbae Blackfin arch: punt CONFIG_BFIN -- we already have CONFIG_BLACKFIN
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-23 14:28:44 +08:00
Mike Frysinger e4e9a7adeb Blackfin arch: fix indentation -- use tabs, not spaces
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 20:39:34 +08:00
Mike Frysinger 4f25eb85d6 Blackfin arch: split board selection off into mach subdirs
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 20:49:44 +08:00
Mike Frysinger d07f438031 Blackfin arch: fix silicon rev display and selection for BF52x/BF54x
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 15:49:17 +08:00
Mike Frysinger fa43cd8b10 Blackfin arch: add a compatible DOUBLE_FAULT define to enable resets on double faults in either core
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-13 00:31:33 +08:00
Mike Frysinger 53f8a252df Blackfin arch: remove mention of uClinux/no-mmu ... we are just Blackfin Linux
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 15:48:01 +08:00
Javier Herrero 51e7f6830f Blackfin arch: Default config for HV Sistemas H8606 board
Signed-off-by: Javier Herrero <jherrero@hvsistemas.es>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 15:45:33 +08:00
Robin Getz 6a3f0b460c Blackfin arch: fix bug cplbmgr.S does not exit properly on error condition
https://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=1685

Ensure that cache/protection is turned back on when we get a
fault, and ensure that the initial population of the CPLB tables are
correct - that kernel is locked in CPLB tables

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-15 15:10:48 +08:00
Michael Hennerich 0954f70ab1 Blackfin arch: fix AD7877 bus_num and add support for WM8731 SPI control interface
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-13 00:16:19 +08:00
Bryan Wu 5d448dd507 Blackfin arch: move hard coded pin_req to board file
Remove some sort of bloaty code, try to get these pin_req arrays built at compile-time

 - move this static things to the blackfin board file
 - add pin_req array to struct bfin5xx_spi_master
 - tested on BF537/BF548 with SPI flash

Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-12 23:24:42 +08:00
Robin Getz 4a589e1ef6 Blackfin arch: fix bux - only reset the PC when necessary, otherwise gdb gets confused
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-12 22:46:46 +08:00
Robin Getz f26fbc48f1 Blackfin arch: ensure we work around ANOMALY_05000261 for null pointers
We currently do not. Also make it easier to handle cplb violations - in traps.c

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-12 22:21:30 +08:00
Linus Torvalds 2ffbb8377c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86:
  x86: simplify "make ARCH=x86" and fix kconfig all.config
  x86: reboot fixup for wrap2c board
  x86: check boundary in count setup resource
  x86: fix reboot with no keyboard attached
  x86: add hpet sanity checks
  x86: on x86_64, correct reading of PC RTC when update in progress in time_64.c
  x86: fix freeze in x86_64 RTC update code in time_64.c
  ntp: fix typo that makes sync_cmos_clock erratic
  Remove x86 merge artifact from top Makefile
  x86: fixup cpu_info array conversion
  x86: show cpuinfo only for online CPUs
  x86: fix cpu-hotplug regression
  x86: ignore the sys_getcpu() tcache parameter
  x86: voyager use correct header file name
  x86: fix smp init sections
  x86: fix voyager_cat_init section
  x86: fix bogus memcpy in es7000_check_dsdt()
2007-11-17 08:36:10 -08:00
Sam Ravnborg 6840999b19 x86: simplify "make ARCH=x86" and fix kconfig all.config
Simplify "make ARCH=x86" and fix kconfig so we again can set 64BIT in
all.config.

For a fix the diffstat is nice:
 6 files changed, 3 insertions(+), 36 deletions(-)

The patch reverts these commits:
 - 0f855aa64b ("kconfig: add helper to set
   config symbol from environment variable")
 - 2a113281f5 ("kconfig: use $K64BIT to
   set 64BIT with all*config targets")

Roman Zippel pointed out that kconfig supported string compares so
the additional complexity introduced by the above two patches were
not needed.

With this patch we have following behaviour:

  # make {allno,allyes,allmod,rand}config [ARCH=...]
  option \ host arch      | 32bit         | 64bit
  =====================================================
  ./.                     | 32bit         | 64bit
  ARCH=x86                | 32bit         | 32bit
  ARCH=i386               | 32bit         | 32bit
  ARCH=x86_64             | 64bit         | 64bit

The general rule are that ARCH= and native architecture takes
precedence over the configuration.

So make ARCH=i386 [whatever] will always build a 32-bit kernel
no matter what the configuration says.  The configuration will
be updated to 32-bit if it was configured to 64-bit and the
other way around.

This behaviour is consistent with previous behaviour so no
suprises here.

make ARCH=x86 will per default result in a 32-bit kernel but as
the only ARCH= value x86 allow the user to select between 32-bit
and 64-bit using menuconfig.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andreas Herrmann <aherrman@arcor.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-17 08:35:43 -08:00
Sam Ravnborg 80ef88d6d2 x86: simplify "make ARCH=x86" and fix kconfig all.config
Simplify "make ARCH=x86" and fix kconfig so we again
can set 64BIT in all.config.

For a fix the diffstat is nice:
 6 files changed, 3 insertions(+), 36 deletions(-)

The patch reverts these commits:
0f855aa64b
-> kconfig: add helper to set config symbol from environment variable

2a113281f5
-> kconfig: use $K64BIT to set 64BIT with all*config targets

Roman Zippel pointed out that kconfig supported string
compares so the additional complexity introduced by the
above two patches were not needed.

With this patch we have following behaviour:

# make {allno,allyes,allmod,rand}config [ARCH=...]
option \ host arch      | 32bit         | 64bit
=====================================================
./.                     | 32bit         | 64bit
ARCH=x86                | 32bit         | 32bit
ARCH=i386               | 32bit         | 32bit
ARCH=x86_64             | 64bit         | 64bit

The general rule are that ARCH= and native architecture
takes precedence over the configuration.
So make ARCH=i386 [whatever] will always build a 32-bit
kernel no matter what the configuration says.
The configuration will be updated to 32-bit if it was
configured to 64-bit and the other way around.

This behaviour is consistent with previous behaviour so
no suprises here.

make ARCH=x86 will per default result in a 32-bit kernel
but as the only ARCH= value x86 allow the user to select
between 32-bit and 64-bit using menuconfig. 

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andreas Herrmann <aherrman@arcor.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
2007-11-17 17:21:54 +01:00
Denys 6d1b30e30c x86: reboot fixup for wrap2c board
Needed to make the wireless board, WRAP2C reboot.

Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-17 16:27:02 +01:00
Yinghai Lu 3d9befd2cd x86: check boundary in count setup resource
need to check info->res_num less than PCI_BUS_NUM_RESOURCES, so
info->bus->resource[info->res_num] = res will not beyond of bus resource
array when acpi returns too many resource entries.

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Gary Hade <gary.hade@us.ibm.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-17 16:27:01 +01:00
Truxton Fulton 05dfa35e84 x86: fix reboot with no keyboard attached
Attempt to fix http://bugzilla.kernel.org/show_bug.cgi?id=8378

Hiroto Shibuya wrote to tell me that he has a VIA EPIA-EK10000 which
suffers from the reboot problem when no keyboard is attached.  My first
patch works for him:

  http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=59f4e7d572980a521b7bdba74ab71b21f5995538

But the latest patch does not work for him :

  http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=8b93789808756bcc1e5c90c99f1b1ef52f839a51

We found that it was necessary to also set the "disable keyboard" flag in
the command byte, as the first patch was doing.  The second patch tries to
minimally modify the command byte, but it is not enough.

Please consider this simple one-line patch to help people with low end VIA
motherboards reboot when no keyboard is attached.  Hiroto Shibuya has
verified that this works for him (as I no longer have an afflicted
machine).


Additional discussion:

Note that original patch from Truxton DOES
disable keyboard and this has been in main tree since 2.6.14, thus it must have
quite a bit of air time already.

http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.14.y.git;a=commit;h=59f4e7d572980a521b7bdba74ab71b21f5995538

Note that he only mention "System flag" in the description and comment, but
in the code, "disable keyboard" flag is set.

  outb(0x14, 0x60);       /* set "System flag" */

In 2.6.23, he made a change to read the current byte and then mask the flags,
but along this change,  he only set the "System flag" and dropped the setting
of "disable keyboard" flag.

http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.23.y.git;a=commit;h=8b93789808756bcc1e5c90c99f1b1ef52f839a51

   outb(cmd | 0x04, 0x60); /* set "System flag" */

So my request is to restore the setting of disable keyboard flag which has been
there since 2.6.14 but disappeared in 2.6.23.

Cc: Lee Garrett <lee-in-berlin@web.de>
Cc: "Hiroto Shibuya" <hiroto.shibuya@gmail.com>
Cc: Natalie Protasevich <protasnb@gmail.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Aristeu Rozanski <aris@ruivo.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-17 16:27:01 +01:00
Thomas Gleixner f4df73c291 x86: add hpet sanity checks
Some BIOSes advertise HPET at 0x0. We really do no want to 
allocate a resource there. Check for it and leave early.

Other BIOSes tell us the HPET is at 0xfed0000000000000 
instead of 0xfed00000. Add a check and fix it up with a warning
on user request.


Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-17 16:27:01 +01:00
David P. Reed bbbd99955b x86: on x86_64, correct reading of PC RTC when update in progress in time_64.c
Correct potentially unstable PC RTC time register reading in time_64.c

Stop the use of an incorrect technique for reading the standard PC RTC
timer, which is documented to "disconnect" time registers from the bus
while updates are in progress.  The use of UIP flag while interrupts
are disabled to protect a 244 microsecond window is one of the
Motorola spec sheet's documented ways to read the RTC time registers
reliably.

tglx: removed locking changes from original patch, as they gain nothing
(read_persistent_clock is only called during boot, suspend, resume - so
no hot path affected) and conflict with the paravirt locking scheme
(see 32bit code), which we do not want to complicate for no benefit.

Signed-off-by: David P. Reed <dpreed@reed.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-17 16:27:01 +01:00
David P. Reed c399da0d97 x86: fix freeze in x86_64 RTC update code in time_64.c
Fix hard freeze on x86_64 when the ntpd service calls 
update_persistent_clock()

A repeatable but randomly timed freeze has been happening in Fedora 6
and 7 for the last year, whenever I run the ntpd service on my AMD64x2
HP Pavilion dv9000z laptop.  This freeze is due to the use of
spin_lock(&rtc_lock) under the assumption (per a bad comment) that
set_rtc_mmss is called only with interrupts disabled.  The call from
ntp.c to update_persistent_clock is made with interrupts enabled.

Signed-off-by: David P. Reed <dpreed@reed.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-17 16:27:01 +01:00