powerpc: Use of_property_present() for testing DT property presence

It is preferred to use typed property access functions (i.e.
of_property_read_<type> functions) rather than low-level
of_get_property/of_find_property functions for reading properties. As
part of this, convert of_get_property/of_find_property calls to the
recently added of_property_present() helper when we just want to test
for presence of a property and nothing more.

Signed-off-by: Rob Herring <robh@kernel.org>
[mpe: Drop change in ppc4xx_probe_pci_bridge(), formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230310144657.1541039-1-robh@kernel.org

powerpc: fix typos in comments

Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220430185654.5855-1-Julia.Lawall@inria.fr

powerpc/powernv: add missing of_node_put

for_each_compatible_node performs an of_node_get on each iteration, so
a break out of the loop requires an of_node_put.

A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):

// <smpl>
@@
local idexpression n;
expression e;
@@

for_each_compatible_node(n,...) {
...
(
of_node_put(n);
|
e = n
|
+ of_node_put(n);
? break;
)
...
}
... when != n
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1448051604-25256-4-git-send-email-Julia.Lawall@lip6.fr

powerpc: rename powerpc_debugfs_root to arch_debugfs_dir

No functional change in this patch. arch_debugfs_dir is the generic kernel
name declared in linux/debugfs.h for arch-specific debugfs directory.
Architectures like x86/s390 already use the name. Rename powerpc
specific powerpc_debugfs_root to arch_debugfs_dir.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210812132831.233794-2-aneesh.kumar@linux.ibm.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove 'type' argument from access_ok() function

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

- csky still had the old "verify_area()" name as an alias.

- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)

- microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

powerpc: Create asm/debugfs.h and move powerpc_debugfs_root there

powerpc_debugfs_root is the dentry representing the root of the
"powerpc" directory tree in debugfs.

Currently it sits in asm/debug.h, a long with some other things that
have "debug" in the name, but are otherwise unrelated.

Pull it out into a separate header, which also includes linux/debugfs.h,
and convert all the users to include debugfs.h instead of debug.h.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/opal-lpc: Remove unneeded include

We don't need asm/xics.h

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Fix section mismatch from opal_lpc_init()

opal_lpc_init() is called from an __init routine, and calls other __init
routines, so should also be __init, init?

Fixes: 023b13a50183 ("powerpc/powernv: Add support for direct mapped LPC on POWER9")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Add support for direct mapped LPC on POWER9

Use the new non-PCI ISA bridge support to expose the POWER9
LPC bus as direct mapped via the ISA IO port range. This
enables direct access via drivers such as 8250

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: Move isa bridge definitions to separate include

We'll be adding non-PCI isa bridge support so let's not
have all the definition in pci-bridge.h

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

This was entirely automated, using the script by Al:

PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

powerpc/powernv: Properly fix LPC debugfs endianness

Endian is hard, especially when I designed a stupid FW interface, and
I should know better... oh well, this is attempt #2 at fixing this
properly. This time it seems to work with all access sizes and I
can run my flashing tool (which exercises all sort of access sizes
and types to access the SPI controller in the BMC) just fine.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@vger.kernel.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Revert "powerpc/powernv: Fix endian bug in LPC bus debugfs accessors"

This reverts commit bf7588a0859580a45c63cb082825d77c13eca357.

Ben says although the code is not correct "[this] fix was completely
wrong and does more damages than it fixes things."

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Fix endian bug in LPC bus debugfs accessors

When reading from the LPC, the OPAL FW calls return the value via pointer
to a uint32_t which is always returned big endian. Our internal inb/outb
implementation byteswaps that fine but our debugfs code is still broken.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Switch powernv drivers to use machine_xxx_initcall()

A lot of the code in platforms/powernv is using non-machine initcalls.
That means if a kernel built with powernv support runs on another
platform, for example pseries, the initcalls will still run.

That is usually OK, because the initcalls will check for something in
the device tree or elsewhere before doing anything, so on other
platforms they will usually just return.

But it's fishy for powernv code to be running on other platforms, so
switch them all to be machine initcalls. If we want any of them to run
on other platforms in future they should move to sysdev.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/powernv: Add missing include to LPC code

kbuild bot spotted that one:

arch/powerpc/platforms/powernv/opal-lpc.c: In function 'opal_lpc_init_debugfs':
>> arch/powerpc/platforms/powernv/opal-lpc.c:319:35: error: 'powerpc_debugfs_root' undeclared (first use in this function)
root = debugfs_create_dir("lpc", powerpc_debugfs_root);
^
We neet to include the definition explicitely.

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

powerpc/powernv: Provide debugfs access to the LPC bus via OPAL

This provides debugfs files to access the LPC bus on Power8
non-virtualized using the appropriate OPAL firmware calls.

The usage is simple: one file per space (IO, MEM and FW),
lseek to the address and read/write the data. IO and MEM always
generate series of byte accesses. FW can generate word and dword
accesses if aligned properly.

Based on an original patch from Rob Lippert and reworked.

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

powerpc/powernv: Fix OPAL LPC access in Little Endian

We are passing pointers to the firmware for reads, we need to properly
convert the result as OPAL is always BE.

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

powerpc: add explicit OF includes

When removing prom.h include by of.h, several OF headers will no longer
be implicitly included. Add explicit includes of of_*.h as needed.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: linuxppc-dev@lists.ozlabs.org

powerpc/powernv: Add PIO accessors for Power8 LPC bus

This uses the hooks provided by CONFIG_PPC_INDIRECT_PIO to
implement a set of hooks for IO port access to use the LPC
bus via OPAL calls for the first 64K of IO space

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