The presense of a writeq() implementation on 32-bit x86 that splits the
64-bit write into two 32-bit writes turns out to break the mpt2sas driver
(and in general is risky for drivers as was discussed in
<http://lkml.kernel.org/r/adaab6c1h7c.fsf@cisco.com>). To fix this,
revert 2c5643b1c5 ("x86: provide readq()/writeq() on 32-bit too") and
follow-on cleanups.
This unfortunately leads to pushing non-atomic definitions of readq() and
write() to various x86-only drivers that in the meantime started using the
definitions in the x86 version of <asm/io.h>. However as discussed
exhaustively, this is actually the right thing to do, because the right
way to split a 64-bit transaction is hardware dependent and therefore
belongs in the hardware driver (eg mpt2sas needs a spinlock to make sure
no other accesses occur in between the two halves of the access).
Build tested on 32- and 64-bit x86 allmodconfig.
Link: http://lkml.kernel.org/r/x86-32-writeq-is-broken@mdm.bga.com
Acked-by: Hitoshi Mitake <h.mitake@gmail.com>
Cc: Kashyap Desai <Kashyap.Desai@lsi.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Ravi Anand <ravi.anand@qlogic.com>
Cc: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Jason Uhlenkott <juhlenko@akamai.com>
Acked-by: James Bottomley <James.Bottomley@parallels.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some of the IBM servers that are supported by ibm_rtl
can run in both Legacy mode (BIOS) and in UEFI mode.
When running in UEFI mode, it is possible that the
EBDA table exists but cannot be mapped and reports
errors. We need to make sure that by default we don't
try to probe the machines if they are running in UEFI
mode.
Signed-off-by: Vernon Mauery <vernux@us.ibm.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Allow all IBM machines to pass the DMI check so that we
don't have to add them one by one to the driver. Any IBM
machine that has the _RTL_ table in the EBDA will work.
Signed-off-by: Vernon Mauery <vernux@us.ibm.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Fix printk format warning:
drivers/platform/x86/ibm_rtl.c:305:warning: format '%#llx' expects type 'long long unsigned int', but argument 2 has type 'phys_addr_t'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Keith Mannthey <kmannth@us.ibm.com>
Cc: Vernon Mauery <vernux@us.ibm.com>
Cc: platform-driver-x86@vger.kernel.org
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
After a period of RFC for this driver, I think it is ready
for inclusion in the platform-driver-x86 tree, hopefully to
be staged in the next merge window into Linus's tree.
--Vernon
------------------------------------------------------------
IBM Real-Time "SMI Free" mode driver
This driver supports the Real-Time Linux (RTL) BIOS feature.
The RTL feature allows non-fatal System Management Interrupts
(SMIs) to be disabled on supported IBM platforms and is
intended to be coupled with a user-space daemon to monitor
the hardware in a way that can be prioritized and scheduled
to better suit the requirements for the system.
The Device is presented as a special "_RTL_" table to the OS
in the Extended BIOS Data Area. There is a simple protocol
for entering and exiting the mode at runtime. This driver
creates a simple sysfs interface to allow a simple entry and
exit from RTL mode in the UFI/BIOS.
Since the driver is specific to IBM SystemX hardware (x86-
based servers) it only builds on x86 builds. To reduce the
risk of loading on the wrong hardware, the module uses DMI
information and checks a list of servers that are known to
work.
Signed-off-by: Vernon Mauery <vernux@us.ibm.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Roland Dreier