The systemcfg data has nothing to do anymore with the vdso.
Split it into a dedicated header file.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20241010-vdso-generic-base-v1-27-b64f0842d512@linutronix.de

The systemcfg data only has minimal overlap with the vdso data.
Splitting the two avoids mapping the implementation-defined vdso data
into /proc/ppc64/systemcfg.
It is also a preparation for the standardization of vdso data storage.

The only field actually used by both systemcfg and vdso is
tb_ticks_per_sec and it is only changed once during time_init().
Initialize it in both structures there.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20241010-vdso-generic-base-v1-26-b64f0842d512@linutronix.de

_be32 type is defined for some elements in pseries_hp_errorlog
struct but also used them u32 after be32_to_cpu() conversion.

Example: In handle_dlpar_errorlog()
hp_elog->_drc_u.drc_index = be32_to_cpu(hp_elog->_drc_u.drc_index);

And later assigned to u32 type
dlpar_cpu() - u32 drc_index = hp_elog->_drc_u.drc_index;

This incorrect usage is giving the following warnings and the
patch resolve these warnings with the correct assignment.

arch/powerpc/platforms/pseries/dlpar.c:398:53: sparse: sparse:
incorrect type in argument 1 (different base types) @@
expected unsigned int [usertype] drc_index @@
got restricted __be32 [usertype] drc_index @@
...
arch/powerpc/platforms/pseries/dlpar.c:418:43: sparse: sparse:
incorrect type in assignment (different base types) @@
expected restricted __be32 [usertype] drc_count @@
got unsigned int [usertype] @@

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202408182142.wuIKqYae-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202408182302.o7QRO45S-lkp@intel.com/
Signed-off-by: Haren Myneni <haren@linux.ibm.com>

v3:
- Fix warnings from using incorrect data types in pseries_hp_errorlog
  struct
v2:
- Remove pr_info() and TODO comments
- Update more information in the commit logs

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240822025028.938332-1-haren@linux.ibm.com

Integrate with the generic SMT support, so that when a CPU is DLPAR
onlined it is brought up with the correct SMT mode.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230705145143.40545-11-ldufour@linux.ibm.com

As part of the generic HOTPLUG_SMT code, there is support for disabling
secondary SMT threads at boot time, by passing "nosmt" on the kernel
command line.

The way that is implemented is the secondary threads are brought partly
online, and then taken back offline again. That is done to support x86
CPUs needing certain initialisation done on all threads. However powerpc
has similar needs, see commit d70a54e2d085 ("powerpc/powernv: Ignore
smt-enabled on Power8 and later").

For that to work the powerpc CPU hotplug callbacks need to be registered
before secondary CPUs are brought online, otherwise __cpu_disable()
fails due to smp_ops->cpu_disable being NULL.

So split the basic initialisation into pseries_cpu_hotplug_init() which
can be called early from setup_arch(). The DLPAR related initialisation
can still be done later, because it needs to do allocations.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230705145143.40545-9-ldufour@linux.ibm.com

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

With the tokens for all implemented RTAS functions now available via
rtas_function_token(), which is optimal and safe for arbitrary
contexts, there is no need to use rtas_token() or cache its result.

Most conversions are trivial, but a few are worth describing in more
detail:

* Error injection token comparisons for lockdown purposes are
  consolidated into a simple predicate: token_is_restricted_errinjct().

* A couple of special cases in block_rtas_call() do not use
  rtas_token() but perform string comparisons against names in the
  function table. These are converted to compare against token values
  instead, which is logically equivalent but less expensive.

* The lookup for the ibm,os-term token can be deferred until needed,
  instead of caching it at boot to avoid device tree traversal during
  panic.

* Since rtas_function_token() accesses a read-only data structure
  without taking any locks, xmon's lookup of set-indicator can be
  performed as needed instead of cached at startup.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230125-b4-powerpc-rtas-queue-v3-20-26929c8cce78@linux.ibm.com

The VPA should unregister when offlining a CPU. Otherwise there could be
a short window where 2 CPUs could share the same VPA.

This happens because the hypervisor is still keeping the VPA attached to
the vCPU even if it became offline.

Here is a potential situation:
 1. remove proc A,
 2. add proc B. If proc B gets proc A's place in cpu_present_mask, then
    it registers proc A's VPAs.
 3. If proc B is then re-added to the LP, its threads are sharing VPAs
    with proc A briefly as they come online.

As the hypervisor may check for the VPA's yield_count field oddity, it
may detect an unexpected value and kill the LPAR.

Suggested-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
[mpe: s/cpu_present_map/cpu_present_mask/ in change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221114160150.13554-1-ldufour@linux.ibm.com

In pseries_cpuhp_cache_use_count() and pseries_cpuhp_detach_nodes(),
we need carefully hold the reference returned by
of_find_next_cache_node() and use it to call of_node_put() to keep
refcount balance.

Signed-off-by: Liang He <windhl@126.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220621111701.4082889-1-windhl@126.com

powerpc is the only platform that do not rely on
cpu_up()->try_online_node() to bring up a numa node,
and special cases it, instead, deep in its own machinery:

dlpar_online_cpu
 find_and_online_cpu_nid
  try_online_node

This should not be needed, but the thing is that the try_online_node()
from cpu_up() will not apply on the right node, because cpu_to_node()
will return the old mapping numa<->cpu that gets set on boot stage
for all possible cpus.

That can be seen easily if we try to print out the numa node passed
to try_online_node() in cpu_up().

The thing is that the numa<->cpu mapping does not get updated till a much
later stage in start_secondary:

start_secondary:
 set_numa_node(numa_cpu_lookup_table[cpu])

But we do not really care, as we already now the
CPU <-> NUMA associativity back in find_and_online_cpu_nid(),
so let us make use of that and set the proper numa<->cpu mapping,
so cpu_to_node() in cpu_up() returns the right node and
try_online_node() can do its work.

Signed-off-by: Oscar Salvador <osalvador@suse.de>
Tested-by: Geetika Moolchandani <Geetika.Moolchandani1@ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220411074934.4632-1-osalvador@suse.de