The cpu_spec is a struct holding various information about the CPU the
kernel is executing on. It's populated early in boot and must not change
after that.
In particular the cpu_features and mmu_features hold the set of
discovered CPU/MMU features and are used to set static keys for each
feature, and do binary patching of assembly. So any change to the
cpu_features/mmu_features later in boot will not be reflected in
the state of the static keys or patched code.
There is already logic to check that cpu_features/mmu_features don't
change, see check_features() in feature-fixups.c.
But as another layer of protection the entire cpu_spec should be read
only after init, annotate it as such.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231025012452.1985680-1-mpe@ellerman.id.au
cpu_specs[] is full of #ifdefs depending on the different
types of CPU.
CPUs are mutually exclusive, it is therefore possible to split
cpu_specs[] into smaller more readable pieces.
Create cpu_specs_XXX.h that will each be dedicated on one
of the following mutually exclusive families:
- 40x
- 44x
- 47x
- 8xx
- e500
- book3s/32
- book3s/64
In book3s/32, the block for 603 has been moved in front in order
to not have two 604 blocks.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Fix CONFIG_47x to be CONFIG_PPC_47x, tweak some formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a44b865e0318286155273b10cdf524ab697928c1.1663606875.git.christophe.leroy@csgroup.eu
The only 64-bit Book3E CPUs we support require the selection
of CONFIG_PPC_E500MC.
However our Kconfig allows configurating a kernel that has 64-bit
Book3E support, but without CONFIG_PPC_E500MC enabled. Such a kernel
would never boot, it doesn't know about any CPUs.
To fix this, force CONFIG_PPC_E500MC to be selected whenever we are
building a 64-bit Book3E kernel.
And add a test to detect future situations where cpu_specs is empty.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ae5d8b8b3ccc346e61d2ec729767f92766273f0b.1663606875.git.christophe.leroy@csgroup.eu
The hardware bug in POWER9 preventing use of the DAWR was fixed in
DD2.3. Set the CPU_FTR_DAWR feature bit on these newer systems to start
using it again, and update the documentation accordingly.
The CPU features for DD2.3 are currently determined by "DD2.2 or later"
logic. In adding DD2.3 as a discrete case for the first time here, I'm
carrying the quirks of DD2.2 forward to keep all behavior outside of
this DAWR change the same. This leaves the assessment and potential
removal of those quirks on DD2.3 for later.
Signed-off-by: Reza Arbab <arbab@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220503170152.23412-1-arbab@linux.ibm.com
When the mmu_feature_keys[] was introduced in the commit c12e6f24d4
("powerpc: Add option to use jump label for mmu_has_feature()"),
it is unlikely that it would be used either directly or indirectly in
the out of tree modules. So we exported it as GPL only.
But with the evolution of the codes, especially the PPC_KUAP support, it
may be indirectly referenced by some primitive macro or inline functions
such as get_user() or __copy_from_user_inatomic(), this will make it
impossible to build many non GPL modules (such as ZFS) on ppc
architecture. Fix this by exposing the mmu_feature_keys[] to the non-GPL
modules too.
Fixes: 7613f5a66b ("powerpc/64s/kuap: Use mmu_has_feature()")
Reported-by: Nathaniel Filardo <nwfilardo@gmail.com>
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220329085709.4132729-1-haokexin@gmail.com
The "oprofile" user-space tools don't use the kernel OPROFILE support
any more, and haven't in a long time. User-space has been converted to
the perf interfaces.
This commits stops building oprofile for powerpc and removes any
reference to it from directories in arch/powerpc/ apart from
arch/powerpc/oprofile, which will be removed in the next commit (this is
broken into two commits as the size of the commit became very big, ~5k
lines).
Note that the member "oprofile_cpu_type" in "struct cpu_spec" isn't
removed as it was also used by other parts of the code.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Robert Richter <rric@kernel.org>
Acked-by: William Cohen <wcohen@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
book3s/32 has two main families:
- CPU with 603 cores that don't have HASH PTE table and
perform SW TLB loading.
- Other CPUs based on 604+ cores that have HASH PTE table.
This leads to some complex logic and additionnal code to
support both. This makes sense for distribution kernels
that aim at running on any CPU, but when you are fine
tuning a kernel for an embedded 603 based board you
don't need all the HASH logic.
Allow selection of support for each family, in order to opt
out unneeded parts of code. At least one must be selected.
Note that some of the CPU supporting HASH also support SW TLB
loading, however it is not supported by Linux kernel at the
time being, because they do not have alternate registers in
the TLB miss exception handlers.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8dde0cdb629a71abc29b0d85a52a86e920376cb6.1603348103.git.christophe.leroy@csgroup.eu
The only thing keeping the cpu_setup() and cpu_restore() functions
used in the cputable entries for Power7, Power8, Power9 and Power10 in
assembly was cpu_restore() being called before there was a stack in
generic_secondary_smp_init(). Commit ("powerpc/64: Set up a kernel
stack for secondaries before cpu_restore()") means that it is now
possible to use C.
Rewrite the functions in C so they are a little bit easier to read.
This is not changing their functionality.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Tweak copyright and authorship notes]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201014072837.24539-2-jniethe5@gmail.com
ISA v3.1 removes transactional memory and hence it should not be present
in cpu_features or cpu_user_features2. Remove CPU_FTR_TM_COMP from
CPU_FTRS_POWER10. Remove PPC_FEATURE2_HTM_COMP and
PPC_FEATURE2_HTM_NOSC_COMP from COMMON_USER2_POWER10.
Fixes: a3ea40d5c7 ("powerpc: Add POWER10 architected mode")
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200827035529.900-1-jniethe5@gmail.com
__machine_check_early_realmode_p*() are currently declared as extern
in cputable.c and because of this when compiled with "C=1" (which
enables semantic checker) produces these warnings.
CHECK arch/powerpc/kernel/mce_power.c
arch/powerpc/kernel/mce_power.c:709:6: warning: symbol '__machine_check_early_realmode_p7' was not declared. Should it be static?
arch/powerpc/kernel/mce_power.c:717:6: warning: symbol '__machine_check_early_realmode_p8' was not declared. Should it be static?
arch/powerpc/kernel/mce_power.c:722:6: warning: symbol '__machine_check_early_realmode_p9' was not declared. Should it be static?
arch/powerpc/kernel/mce_power.c:740:6: warning: symbol '__machine_check_early_realmode_p10' was not declared. Should it be static?
Patch here moves the declaration to asm/mce.h and includes the same in
cputable.c
Fixes: ae744f3432 ("powerpc/book3s: Flush SLB/TLBs if we get SLB/TLB machine check errors on power8")
Fixes: 7b9f71f974 ("powerpc/64s: POWER9 machine check handler")
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200817005618.3305028-1-maddy@linux.ibm.com
Add a raw mode cputable entry for POWER10. Copies most of the fields
from commit a3ea40d5c7 ("powerpc: Add POWER10 architected mode")
except for oprofile_cpu_type, machine_check_early, pvr_mask and
pvr_mask fields. On bare metal systems we use DT CPU features, which
doesn't need a cputable entry. But in VMs we still rely on the raw
cputable entry to set the correct values for the PMU related fields.
Fixes: a3ea40d5c7 ("powerpc: Add POWER10 architected mode")
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
[mpe: Reorder vs cleanup patch and add Fixes tag]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200817005618.3305028-2-maddy@linux.ibm.com
Add support for the scv instruction on POWER9 and later CPUs.
For now this implements the zeroth scv vector 'scv 0', as identical to
'sc' system calls, with the exception that LR is not preserved, nor
are volatile CR registers, and error is not indicated with CR0[SO],
but by returning a negative errno.
rfscv is implemented to return from scv type system calls. It can not
be used to return from sc system calls because those are defined to
preserve LR.
getpid syscall throughput on POWER9 is improved by 26% (428 to 318
cycles), largely due to reducing mtmsr and mtspr.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fix ppc64e build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200611081203.995112-3-npiggin@gmail.com
PVR value of 0x0F000006 means we are arch v3.1 compliant (i.e.
POWER10). This is used by phyp and kvm when booting as a pseries guest
to detect the presence of new P10 features and to enable the
appropriate hwcap and facility bits.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
[mpe: Fall through to __init_FSCR rather than duplicating it, drop
hack to set current->thread.fscr now that is handled elsewhere.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200521014341.29095-8-alistair@popple.id.au