First phase in introducing ACPI support to SN.
In this phase, when running with an ACPI capable PROM,
the DSDT will define the root busses and all SN nodes
(SGIHUB, SGITIO). An ACPI bus driver will be registered
for the node devices, with the acpi_pci_root_driver being
used for the root busses. An ACPI vendor descriptor is
now used to pass platform specific information for both
nodes and busses, eliminating the need for the current
SAL calls. Also, with ACPI support, SN fixup code is no longer
needed to initiate the PCI bus scans, as the acpi_pci_root_driver
does that.
However, to maintain backward compatibility with non-ACPI capable
PROMs, none of the current 'fixup' code can been deleted, though
much restructuring has been done. For example, the bulk of the code
in io_common.c is relocated code that is now common regardless
of what PROM is running, while io_acpi_init.c and io_init.c contain
routines specific to an ACPI or non ACPI capable PROM respectively.
A new pci bus fixup platform vector has been created to provide
a hook for invoking platform specific bus fixup from pcibios_fixup_bus().
The size of io_space[] has been increased to support systems with
large IO configurations.
Signed-off-by: John Keller <jpk@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
It turns out msi_ops was simply not enough to abstract the architecture
specific details of msi. So I have moved the resposibility of constructing
the struct irq_chip to the architectures, and have two architecture specific
functions arch_setup_msi_irq, and arch_teardown_msi_irq.
For simple architectures those functions can do all of the work. For
architectures with platform dependencies they can call into the appropriate
platform code.
With this msi.c is finally free of assuming you have an apic, and this
actually takes less code.
The helpers for the architecture specific code are declared in the linux/msi.h
to keep them separate from the msi functions used by drivers in linux/pci.h
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Abstract portions of the MSI core for platforms that do not use standard
APIC interrupt controllers. This is implemented through a new arch-specific
msi setup routine, and a set of msi ops which can be set on a per platform
basis.
Signed-off-by: Mark Maule <maule@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On SN2, MMIO writes which are issued from separate processors are not
guaranteed to arrive in any particular order at the IO hardware. When
performing such writes from the kernel this is not a problem, as a
kernel thread will not migrate to another CPU during execution, and
mmiowb() calls can guarantee write ordering when control of the IO
resource is allowed to move between threads.
However, when MMIO writes can be performed from user space (e.g. DRM)
there are no such guarantees and mechanisms, as the process may
context-switch at any time, and may migrate to a different CPU as part
of the switch. For such programs/hardware to operate correctly, it is
required that the MMIO writes from the old CPU be accepted by the IO
hardware before subsequent writes from the new CPU can be issued.
The following patch implements this behavior on SN2 by waiting for a
Shub register to indicate that these writes have been accepted. This
is placed in the context switch-in path, and only performs the wait
when the newly scheduled task changes CPUs.
Signed-off-by: Prarit Bhargava <prarit@sgi.com>
Signed-off-by: Brent Casavant <bcasavan@sgi.com>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
John Keller