When reading_reply is set, reply_ptr points into an adb_request struct.
Conversely, when reply_ptr instead points into the global cuda_rbuf,
reading_reply must be false.

Unfortunately, this rule can be violated because re-initialization
of reply_ptr and reading_reply presently depends on the TREQ input.

Fix this by re-initializing reply_ptr and reading_reply as soon as they
are known to be invalid.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

If the Cuda driver does not enter the 'read_done' state for some
reason, it may continue in the 'reading' state until the buffer
overflows. Add a bounds check to prevent this.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Introduce some helpers for handling the signalling between VIA and
Cuda. This abstraction will be used to add support for Egret devices,
which utilize slightly different signalling.

Don't invert the sense of the Cuda's active-low signals when storing
them in the 'status' variable. Just assert, negate and test those
signals using the helpers.

The state machine does not need to test its own output signals to
figure out what to do next: the next state depends on the Cuda's TREQ
output. Just call the TREQ_asserted() helper function to test for that.

Similarly, there is no need to store pin directions in the 'status'
variable. That was only useful for debugging messages.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

There is no possibility that current_req can change during execution of
cuda_start(). This can be confirmed by inspection: cuda_lock is always
held whenever cuda_start() is called or current_req is modified.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Add missing log message severity, remove old debug messages and
replace printk() loop with print_hex_dump() call.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Without this we will always find the feature disabled.

Fixes: 984d7a1e

 ("powerpc/mm: Fixup kernel read only mapping")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

start,size has the benefit of being easier to search for (start,end
usually gives you the preceeding vector from the one you want, as first
result).

Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Somewhere along the line, search/replace left some naming garbled,
and untidy alignment (aka. mpe stuffed it up). Might as well fix them
all up now while git blame history doesn't extend too far.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This adds AUX vectors for the L1I,D, L2 and L3 cache levels
providing for each cache level the size of the cache in bytes
and the geometry (line size and number of ways).

We chose to not use the existing alpha/sh definition which
packs all the information in a single entry per cache level as
it is too restricted to represent some of the geometries used
on POWER.

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

All shipping firmware versions have it wrong in the device-tree

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

Retrieved from device-tree when available

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

We have two set of identical struct members for the I and D sides
and mostly identical bunches of code to parse the device-tree to
populate them. Instead make a ppc_cache_info structure with one
copy for I and one for D

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

It will be used to calculate the associativity

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

In a number of places we called "cache line size" what is actually
the cache block size, which in the powerpc architecture, means the
effective size to use with cache management instructions (it can
be different from the actual cache line size).

We fix the naming across the board and properly retrieve both
pieces of information when available in the device-tree.

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

We don't patch instructions based on the cache lines or block
sizes these days.

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

The variables are defined twice in setup_32.c and setup_64.c, do it
once in setup-common.c instead

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

It's an kernel private macro, it doesn't belong there

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

Enable support for GCC plugins on powerpc.

Add an additional version check in gcc-plugins-check to advise users to
upgrade to gcc 5.2+ on powerpc to avoid issues with header files (gcc <=
4.6) or missing copies of rs6000-cpus.def (4.8 to 5.1 on 64-bit
targets).

Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Commit 38addce8 ("gcc-plugins: Add latent_entropy plugin") excludes
certain powerpc early boot code from the latent entropy plugin by adding
appropriate CFLAGS. It looks like this was supposed to cover
prom_init.o, but ended up saying init.o (which doesn't exist) instead.
Fix the typo.

Fixes: 38addce8

 ("gcc-plugins: Add latent_entropy plugin")
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The variable DISABLE_LATENT_ENTROPY_PLUGIN is defined when
CONFIG_PAX_LATENT_ENTROPY is set. This is leftover from the original PaX
version of the plugin code and doesn't actually exist. Change the condition
to depend on CONFIG_GCC_PLUGIN_LATENT_ENTROPY instead.

Fixes: 38addce8

 ("gcc-plugins: Add latent_entropy plugin")
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Stub out the debugfs functions so that the build doesn't break when
CONFIG_DEBUG_FS=n.

Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

As we add the ability to do DLPAR of additional devices through
the sysfs interface we need to know which devices are supported.
This adds the reporting of supported devices with a comma separated
list reported in the existing /sys/kernel/dlpar.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Extend the existing PRRN infrastructure to perform the actual affinity
updating for cpus and memory in addition to the device tree updating.
For cpus, dynamic affinity updating already appears to exist in the
kernel in the form of arch_update_cpu_topology(). For memory, we must
place a READD operation on the hotplug queue for any phandle included in
the PRRN event that is determined to be an LMB.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Currently, memory must be hot removed and subsequently re-added in order
to dynamically update the affinity of LMBs specified by a PRRN event.
Earlier implementations of the PRRN event handler ran into issues in which
the hot remove would occur successfully, but a hotplug event would be
initiated from another source and grab the hotplug lock preventing the hot
add from occurring. To prevent this situation, this patch introduces the
notion of a hot "readd" action for memory which atomizes a hot remove and
a hot add into a single, serialized operation on the hotplug queue.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

When adding and removing LMBs we should make the acquire/release of
the DRC a separate step to allow for a few improvements. First
this will ensure that LMBs removed during a remove by count operation
are all available if a error occurs and we need to add them back. By
first removeing all the LMBs from the kernel before releasing their
DRCs the LMBs are available to add back should an error occur.

Also, this will allow for faster re-add operations of memory for
PRRN event handling since we can skip the unneeded step of having
to release the DRC and the acquire it back.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Add a few things that have been missed from .gitignore over the years.

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

CONFIG_PPC_PTDUMP currently selects CONFIG_DEBUG_FS. But CONFIG_DEBUG_FS
is user-selectable, so we shouldn't select it. Instead depend on it.

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

Commit db911217

 ("powerpc: Turn on BPF_JIT in ppc64_defconfig")
only added BPF_JIT to the ppc64 defconfig. Add it to our powernv
and pseries defconfigs too.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We added support for HAVE_CONTEXT_TRACKING, but placed the option inside
PPC_PSERIES.

This has the undesirable effect that NO_HZ_FULL can be enabled on a
kernel with both powernv and pseries support, but cannot on a kernel
with powernv only support.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

In __get_user_nosleep, we create an intermediate pointer for the
user address we're about to fetch. We currently don't tag this
pointer as const. Make it const, as we are simply dereferencing
it, and it's scope is limited to the __get_user_nosleep macro.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

In __get_user_nocheck, we create an intermediate pointer for the
user address we're about to fetch. We currently don't tag this
pointer as const. Make it const, as we are simply dereferencing
it, and it's scope is limited to the __get_user_nocheck macro.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

In __get_user_check, we create an intermediate pointer for the
user address we're about to fetch. We currently don't tag this
pointer as const. Make it const, as we are simply dereferencing
it, and it's scope is limited to the __get_user_check macro.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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

Fixes: 023b13a5

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

Use remove_pagetable() and friends for radix vmemmap removal.

We do not require the special-case handling of vmemmap done in the x86
versions of these functions. This is because vmemmap_free() has already
freed the mapped pages, and calls us with an aligned address range.

So, add a few failsafe WARNs, but otherwise the code to remove physical
mappings is already sufficient for vmemmap.

Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Tear down and free the four-level page tables of physical mappings
during memory hotremove.

Borrow the basic structure of remove_pagetable() and friends from the
identically-named x86 functions. Reduce the frequency of tlb flushes and
page_table_lock spinlocks by only doing them in the outermost function.
There was some question as to whether the locking is needed at all.
Leave it for now, but we could consider dropping it.

Memory must be offline to be removed, thus not in use. So there
shouldn't be the sort of concurrent page walking activity here that
might prompt us to use RCU.

Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Wire up memory hotplug page mapping for radix. Share the mapping
function already used by radix_init_pgtable().

Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Move the page mapping code in radix_init_pgtable() into a separate
function that will also be used for memory hotplug.

The current goto loop progressively decreases its mapping size as it
covers the tail of a range whose end is unaligned. Change this to a for
loop which can do the same for both ends of the range.

Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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>

The POWER9 chip supports an LPC bus that isn't hanging
off a PCI bus, so let's add support for that, mapping it
to the reserved space at ISA_IO_BASE

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