As described in the help text in the patch, this token restricts general
access to /dev/mem as a way of increasing the security. Specifically, access
to exclusive IOMEM and kernel RAM is denied unless CONFIG_STRICT_DEVMEM is
set to 'n'.

Implement the 'devmem_is_allowed()' interface for Powerpc. It will be
called from range_is_allowed() when userpsace attempts to access /dev/mem.

This patch is based on an earlier patch from Steve Best and with input from
Paul Mackerras and Scott Wood.

[BenH] Fixed a typo or two and removed the generic change which should
       be submitted as a separate patch
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The patch below removes an extra semicolon.
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
CC: linuxppc-dev@lists.ozlabs.org
CC: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

On Fri, Nov 11, 2011 at 10:17:55AM +0530, Ananth N Mavinakayanahalli wrote:
> >
> > At this rate we're going to end up with no bits left for CPU features
> > way too quickly... Especially for something we only care about once at
> > boot time.
> >
> > Wouldn't CPU_FTR_PPCAS_ARCH_V2 be a good enough test ?
>
> /me checks Cell manuals... yes, that test would be good enough. I will
> cook up a patch to use this.

Here it is...
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This adds support for p7IOC (and possibly other IODA v1 IO Hubs)
using OPAL v2 interfaces.

We completely take over resource assignment and assign them using an
algorithm that hands out device BARs in a way that makes them fit in
individual segments of the M32 window of the bridge, which enables us
to assign individual PEs to devices and functions.

The current implementation gives out a PE per functions on PCIe, and a
PE for the entire bridge for PCIe to PCI-X bridges.

This can be adjusted / fine tuned later.

We also setup DMA resources (32-bit only for now) and MSIs (both 32-bit
and 64-bit MSI are supported).

The DMA allocation tries to divide the available 256M segments of the
32-bit DMA address space "fairly" among PEs. This is done using a
"weight" heuristic which assigns less value to things like OHCI USB
controllers than, for example SCSI RAID controllers. This algorithm
will probably want some fine tuning for specific devices or device
types.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

It advertises "host bridge" instead of "PCI to PCI bridge" which confuses
the Linux probe code.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This is used for newer IO Hubs such as p7IOC.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

When PCI_REASSIGN_ALL_RSRC is set, we used to clear all bus resources
at the beginning of survey and re-allocate them later.

This changes it so instead, during early fixup, we mark all resources
as IORESOURCE_UNSET and move them down to be 0-based.

Later, if bus resources are still unset at the beginning of the survey,
then we clear them.

This shouldn't impact the re-assignment case on 4xx, but will enable
us to have the platform do some custom resource assignment before the
survey, by clearing individual resources IORESOURCE_UNSET bit.

Also limits the clutter in the kernel log from fixup when re-assigning
since we don't care about the offset applied to the BAR values in this
case.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Some platforms need to perform resource allocation using a custom algorithm
due to HW constraints, or may want to tweak things globally below a host
bridge. For example OPAL support for IODA will need to perform a
resource allocation pass that applies IODA specific segmentation
constraints to MMIO which cannot be done simply using the kernel generic
resource management code.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This adds a pgprot combination required by some cache-enabled IO device
mappings, such as Freescale datapath (QMan and BMan) portals.
Signed-off-by: Geoff Thorpe <geoff@geoffthorpe.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

All interrupts which must be non threaded are marked
IRQF_NO_THREAD. So it's safe to allow force threaded handlers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

IPI handlers cannot be threaded. Remove the obsolete IRQF_DISABLED
flag (see commit e58aa3d2) while at it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Cascade handlers must run in hard interrupt context.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Cascade interrupt must run in hard interrupt context.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The RTAS firmware flash update is conducted using an RTAS call that is
serialized by lock_rtas() which uses spin_lock. While the flash is in
progress, rtasd performs scan for any RTAS events that are generated by
the system. rtasd keeps scanning for the RTAS events generated on the
machine. This is performed via workqueue mechanism. The rtas_event_scan()
also uses an RTAS call to scan the events, eventually trying to acquire
the spin_lock before issuing the request.

The flash update takes a while to complete and during this time, any other
RTAS call has to wait. In this case, rtas_event_scan() waits for a long time
on the spin_lock resulting in a soft lockup.

Fix: Just before the flash update is performed, the queued rtas_event_scan()
work item is cancelled from the work queue so that there is no other RTAS
call issued while the flash is in progress. After the flash completes, the
system reboots and the rtas_event_scan() is rescheduled.
Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com>
Signed-off-by: Ravi Nittala <ravi.nittala@in.ibm.com>
Reported-by: Divya Vikas <divya.vikas@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This patch add the Chroma platform to WSP/PowerEN, which is a PCIe
card (a defconfig is included).

The card includes an H8 service processor that is used to manage the
card.  The H8 is connected over the second serial UART on the PowerEN
chip so this patch includes a simple 16550 driver to enable
communication, mostly for "power off" and "rebooting".

This patch also includes a, WSP specific, "halt" method that will shut
of all A2 cores but still leave power on at the chip level.  This is
desirable, especially if you wish to interrogate the chip with a
hardware probe after the halt.
Signed-off-by: Jimi Xenidis <jimix@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Sorry, there was a typo in the #if
signed-off-by: Jimi Xenidis <jimix@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The 'u' command will print the TLB on book3e parts and the SLB on
Book3s parts, but the help system doesn't say that correctly.
Signed-off-by: Jimi Xenidis <jimix@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This patch adds a fault handler that responds to illegal Coprocessor
types.  Currently all CTs are treated and illegal.  There are two ways
to report the fault back to the application.  If the application used
the record form ("icswx.") then the architected "reject" is emulated.
If the application did not used the record form ("icswx") then it is
selectable by config whether the failure is silent (as architected) or
a SIGILL is generated.

In all cases pr_warn() is used to log the bad CT.
Signed-off-by: Jimi Xenidis <jimix@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

ICSWX is also used by the A2 processor to access coprocessors,
although not all "chips" that contain A2s have coprocessors.
Signed-off-by: Jimi Xenidis <jimix@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Some processors, like embedded, that already have a PID register that
is managed by the system.  This patch separates the ACOP and PID
processing into separate files so that the ACOP code can be shared.
Signed-off-by: Jimi Xenidis <jimix@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

libio.h is not provided by uClibc, in order to be able to test the
definition of __UCLIBC__ we need to include stdlib.h, which also
includes stddef.h, providing the definition of 'NULL'.
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

np is initialized to the result of calling a function that calls
of_node_get, so of_node_put should be called before the pointer is dropped.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e,e1,e2;
@@

* e = \(of_find_node_by_type\|of_find_node_by_name\)(...)
  ... when != of_node_put(e)
      when != true e == NULL
      when != e2 = e
  e = e1
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

np is initialized to the result of calling a function that calls
of_node_get, so of_node_put should be called before the pointer is dropped.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e,e1,e2;
@@

* e = \(of_find_node_by_type\|of_find_node_by_name\)(...)
  ... when != of_node_put(e)
      when != true e == NULL
      when != e2 = e
  e = e1
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Some pseries IOMMUs cache TCEs but don't snoop when the TCEs are changed
in memory, hence we need manually invalidate in software.

This adds code to do the invalidate.  It keys off a device tree property
to say where the to do the MMIO for the invalidate and some information
on what the format of the invalidate including some magic routing info.

it_busno get overloaded with this magic routing info and it_index with
the MMIO address for the invalidate command.

This then gets hooked into the building and freeing of TCEs.

This is only useful on bare metal pseries.  pHyp takes care of this when
virtualised.

Based on patch from Milton with cleanups from Mikey.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

decrementer_check_overflow is called from arch_local_irq_restore so
we want to make it as light weight as possible. As such, turn
decrementer_check_overflow into an inline function.

To avoid a circular mess of includes, separate out the two components
of struct decrementer_clock and keep the struct clock_event_device
part local to time.c.

The fast path improves from:

arch_local_irq_restore
     0:       mflr    r0
     4:       std     r0,16(r1)
     8:       stdu    r1,-112(r1)
     c:       stb     r3,578(r13)
    10:       cmpdi   cr7,r3,0
    14:       beq-    cr7,24 <.arch_local_irq_restore+0x24>
...
    24:       addi    r1,r1,112
    28:       ld      r0,16(r1)
    2c:       mtlr    r0
    30:       blr

to:

arch_local_irq_restore
    0:       std     r30,-16(r1)
    4:       ld      r30,0(r2)
    8:       stb     r3,578(r13)
    c:       cmpdi   cr7,r3,0
   10:       beq-    cr7,6c <.arch_local_irq_restore+0x6c>
...
   6c:       ld      r30,-16(r1)
   70:       blr

Unfortunately we still setup a local TOC (due to -mminimal-toc). Yet
another sign we should be moving to -mcmodel=medium.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Fix some formatting issues and use the DECREMENTER_MAX
define instead of 0x7fffffff.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The clockevents code uses max_delta_ns to avoid calling a
clockevent with too large a value.

Remove the redundant version of this in the timer_interrupt
code.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Use clocksource_register_hz which calculates the shift/mult
factors for us. Also remove the shift = 22 assumption in
vsyscall_update - thanks to Paul Mackerras and John Stultz for
catching that.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

We can use clockevents_calc_mult_shift instead of doing all
the work ourselves.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

When re-enabling interrupts we have code to handle edge sensitive
decrementers by resetting the decrementer to 1 whenever it is negative.
If interrupts were disabled long enough that the decrementer wrapped to
positive we do nothing. This means interrupts can be delayed for a long
time until it finally goes negative again.

While we hope interrupts are never be disabled long enough for the
decrementer to go positive, we have a very good test team that can
drive any kernel into the ground. The softlockup data we get back
from these fails could be seconds in the future, completely missing
the cause of the lockup.

We already keep track of the timebase of the next event so use that
to work out if we should trigger a decrementer exception.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable@kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The UCC UART driver is missing a call to uart_update_timeout().
Without this call, attempting to close the port after outputting large
amounts of data (i.e. using tty and uart buffering) results in long
timeouts before the port will actually be shut down.

For example, cat a large file to a UCC UART port.  With the current
driver, the port will stay open for 30 seconds after the last byte
of data is output.  But with this patch, the port is closed as
expected, just after the data has been output (tx fifos empty).
Signed-off-by: Chuck Meade <chuck@ThePTRGroup.com>
Acked-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

On Freescale parts with multiple MSI controllers, the controllers are
combined into one "pool" of interrupts.  Whenever a device requests an MSI
interrupt, the next available interrupt from the pool is selected,
regardless of which MSI controller the interrupt is from.  This works
because each PCI bus has an ATMU to all of CCSR, so any PCI device can
access any MSI interrupt register.

The fsl,msi property is used to specify that a given PCI bus should only
use a specific MSI device.  This is necessary, for example, with the
Freescale hypervisor, because the MSI devices are assigned to specific
partitions.

Ideally, we'd like to be able to assign MSI devices to PCI busses within
the MSI or PCI layers.  However, there does not appear to be a mechanism
to do that.  Whenever the MSI layer wants to allocate an MSI interrupt to
a PCI device, it just calls arch_setup_msi_irqs().  It would be nice if we
could register an MSI device with a specific PCI bus.

So instead we remember the phandles of each MSI device, and we use that to
limit our search for an available interrupt.  Whenever we are asked to
allocate a new interrupt for a PCI device, we check the fsl,msi property
of the PCI bus for that device.  If it exists, then as we are looping over
all MSI devices, we skip the ones that don't have a matching phandle.
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

The file name is already scoped by the directory its in.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

P1010RDB & P1023RDS can use the new mpc85xx_common_publish_devices().
Also move 'fsl,srio' into the list of standard buses.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

85xx board files have a lot of duplication in *_publish_devices()/
*_declare_of_platform_devices() functions. Merge that into a single
function common to most of the boards.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

Separate handling of CPM2 PIC initialization to mpc85xx_cpm2_pic_init()
function.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

Traditionally mpc830x_rdb board file searched for mpc8308-pcie devices.
However both in-kernel dts from the beginning declared those pcie units
as compatible with mpc8314-pci, which is handled by mpc83xx_setup_pci().

Drop special handling for mpc8308 and use common function instead.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

Nearly all mpc83xx-based boards have a common piece of code - one that
loops over all pci/pcie bridges and registers them. Merge that code into
a special function common to all boards.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

83xx board files have a lot of duplication in
*_declare_of_platform_devices() functions. Merge that into a single
function common to most of the boards.

The only leftover is mpc834x_itx.c board file which explicitly asks for
fsl,pq2pro-localbus, as corresponding bindings don't provide
"simple-bus" compatibility in localbus node.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>