powerpc/pseries: Move dtl scanning and steal time accounting to pseries platform

dtl is the PAPR Dispatch Trace Log, which is entirely a pseries feature.
The pseries platform alrady has a file deali

powerpc/pseries: Move dtl scanning and steal time accounting to pseries platform

dtl is the PAPR Dispatch Trace Log, which is entirely a pseries feature.
The pseries platform alrady has a file dealing with the dtl, so move
scanning for stolen time accounting there from kernel/time.c.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220902085316.2071519-5-npiggin@gmail.com

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powerpc/time: Fix sparse warnings

We found these warnings in arch/powerpc/kernel/time.c as follows:
warning: symbol 'decrementer_max' was not declared. Should it be static?
warning: symbol 'rtc_

powerpc/time: Fix sparse warnings

We found these warnings in arch/powerpc/kernel/time.c as follows:
warning: symbol 'decrementer_max' was not declared. Should it be static?
warning: symbol 'rtc_lock' was not declared. Should it be static?
warning: symbol 'dtl_consumer' was not declared. Should it be static?

Declare 'decrementer_max' in powerpc asm/time.h.

Include linux/mc146818rtc.h in powerpc kernel/time.c where 'rtc_lock' is
declared. And remove duplicated declaration of 'rtc_lock' in powerpc
platforms/chrp/time.c because it has included linux/mc146818rtc.h.

Move 'dtl_consumer' definition after "include <asm/dtl.h>" because it is
declared there.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: He Ying <heying24@huawei.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210324090939.143477-1-heying24@huawei.com

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powerpc/time: add API for KVM to re-arm the host timer/decrementer

Rather than have KVM look up the host timer and fiddle with the
irq-work internal details, have the powerpc/time.c code provide a
f

powerpc/time: add API for KVM to re-arm the host timer/decrementer

Rather than have KVM look up the host timer and fiddle with the
irq-work internal details, have the powerpc/time.c code provide a
function for KVM to re-arm the Linux timer code when exiting a
guest.

This is implementation has an improvement over existing code of
marking a decrementer interrupt as soft-pending if a timer has
expired, rather than setting DEC to a -ve value, which tended to
cause host timers to take two interrupts (first hdec to exit the
guest, then the immediate dec).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211123095231.1036501-8-npiggin@gmail.com

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KVM: PPC: Book3S HV P9: Use large decrementer for HDEC

On processors that don't suppress the HDEC exceptions when LPCR[HDICE]=0,
this could help reduce needless guest exits due to leftover exception

KVM: PPC: Book3S HV P9: Use large decrementer for HDEC

On processors that don't suppress the HDEC exceptions when LPCR[HDICE]=0,
this could help reduce needless guest exits due to leftover exceptions on
entering the guest.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211123095231.1036501-6-npiggin@gmail.com

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KVM: PPC: Book3S HV P9: Use host timer accounting to avoid decrementer read

There is no need to save away the host DEC value, as it is derived
from the host timer subsystem which maintains the next

KVM: PPC: Book3S HV P9: Use host timer accounting to avoid decrementer read

There is no need to save away the host DEC value, as it is derived
from the host timer subsystem which maintains the next timer time,
so it can be restored from there.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211123095231.1036501-5-npiggin@gmail.com

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KVM: PPC: Book3S HV P9: Reduce irq_work vs guest decrementer races

irq_work's use of the DEC SPR is racy with guest<->host switch and guest
entry which flips the DEC interrupt to guest, which could

KVM: PPC: Book3S HV P9: Reduce irq_work vs guest decrementer races

irq_work's use of the DEC SPR is racy with guest<->host switch and guest
entry which flips the DEC interrupt to guest, which could lose a host
work interrupt.

This patch closes one race, and attempts to comment another class of
races.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210528090752.3542186-11-npiggin@gmail.com

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powerpc/time: move timer_broadcast_interrupt prototype to asm/time.h

Interrupt handler prototypes are going to be rearranged in a
future patch, so tidy this out of the way first.

Signed-off-by: Nic

powerpc/time: move timer_broadcast_interrupt prototype to asm/time.h

Interrupt handler prototypes are going to be rearranged in a
future patch, so tidy this out of the way first.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210130130852.2952424-21-npiggin@gmail.com

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powerpc/time: Remove ifdef in get_vtb()

SPRN_VTB and CPU_FTR_ARCH_207S are always defined,
no need of an ifdef.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael

powerpc/time: Remove ifdef in get_vtb()

SPRN_VTB and CPU_FTR_ARCH_207S are always defined,
no need of an ifdef.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a0fc81cd85121407726bcf480fc9a0d8e7617fce.1601549933.git.christophe.leroy@csgroup.eu

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powerpc/time: Move timebase functions into new asm/vdso/timebase.h

In order to easily use get_tb() from C VDSO, move timebase
functions into a new header named asm/vdso/timebase.h

Signed-off-by: Ch

powerpc/time: Move timebase functions into new asm/vdso/timebase.h

In order to easily use get_tb() from C VDSO, move timebase
functions into a new header named asm/vdso/timebase.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201126131006.2431205-3-mpe@ellerman.id.au

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powerpc/time: Make get_tb() common to PPC32 and PPC64

mftbu() is always defined now, so the #ifdef can be removed
and replaced by an IS_ENABLED(CONFIG_PPC64) inside the
PPC32 version of get_tb().

S

powerpc/time: Make get_tb() common to PPC32 and PPC64

mftbu() is always defined now, so the #ifdef can be removed
and replaced by an IS_ENABLED(CONFIG_PPC64) inside the
PPC32 version of get_tb().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/47e49717d2643169ffcbe5d507f184cf49f0fe95.1601556145.git.christophe.leroy@csgroup.eu

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powerpc/time: Make get_tbl() common to PPC32 and PPC64

On PPC64, get_tbl() is defined as an alias of get_tb() which return
the result of mftb(). That exactly the same as what the PPC32 version
does.

powerpc/time: Make get_tbl() common to PPC32 and PPC64

On PPC64, get_tbl() is defined as an alias of get_tb() which return
the result of mftb(). That exactly the same as what the PPC32 version
does. We don't need two versions.

Remove the PPC64 definition of get_tbl() and use the PPC32 version
for both.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a8eaabb87d69534e533ebac805163e08146e05bd.1601556145.git.christophe.leroy@csgroup.eu

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powerpc/time: Remove get_tbu()

get_tbu() is redundant with mftbu() and is not used anymore.

Remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman

powerpc/time: Remove get_tbu()

get_tbu() is redundant with mftbu() and is not used anymore.

Remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1746e2d11ea90c3f45877e1fcc6c79ce96cf6b98.1601556145.git.christophe.leroy@csgroup.eu

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powerpc/time: Avoid using get_tbl() and get_tbu() internally

get_tbl() is confusing as it returns the content of TBL register
on PPC32 but the concatenation of TBL and TBU on PPC64.

Use mftb() inst

powerpc/time: Avoid using get_tbl() and get_tbu() internally

get_tbl() is confusing as it returns the content of TBL register
on PPC32 but the concatenation of TBL and TBU on PPC64.

Use mftb() instead.

Do the same with get_tbu() for consistency allthough it's name
is less confusing.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/41573406a4eab98838decaa91649086fef1e6119.1601556145.git.christophe.leroy@csgroup.eu

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powerpc/time: Rename mftbl() to mftb()

On PPC64, we have mftb().
On PPC32, we have mftbl() and an #define mftb() mftbl().

mftb() and mftbl() are equivalent, their purpose is to read the
content of

powerpc/time: Rename mftbl() to mftb()

On PPC64, we have mftb().
On PPC32, we have mftbl() and an #define mftb() mftbl().

mftb() and mftbl() are equivalent, their purpose is to read the
content of SPRN_TRBL, as returned by 'mftb' simplified instruction.

binutils seems to define 'mftbl' instruction as an equivalent
of 'mftb'.

However in both 32 bits and 64 bits documentation, only 'mftb' is
defined, and when performing a disassembly with objdump, the displayed
instruction is 'mftb'

No need to have two ways to do the same thing with different
names, rename mftbl() to have only mftb().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/94dc68d3d9ef9eb549796d4b938b6ba0305a049b.1601556145.git.christophe.leroy@csgroup.eu

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powerpc/time: Remove ifdef in get_dec() and set_dec()

Move SPRN_PIT definition in reg.h.

This allows to remove ifdef in get_dec() and set_dec() and
makes them more readable.

Signed-off-by: Christo

powerpc/time: Remove ifdef in get_dec() and set_dec()

Move SPRN_PIT definition in reg.h.

This allows to remove ifdef in get_dec() and set_dec() and
makes them more readable.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3c9a6eb0fc040868ac59be66f338d08fd017668d.1601549945.git.christophe.leroy@csgroup.eu

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powerpc: Remove get_tb_or_rtc()

601 is gone, get_tb_or_rtc() is equivalent to get_tb().

Replace the former by the later.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by

powerpc: Remove get_tb_or_rtc()

601 is gone, get_tb_or_rtc() is equivalent to get_tb().

Replace the former by the later.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3e8a13ee83418630c753c30cb722ae682d5b2d39.1601362098.git.christophe.leroy@csgroup.eu

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powerpc: Remove __USE_RTC()

Now that PowerPC 601 is gone, __USE_RTC() is never true.

Remove it.

That also leads to removing get_rtc() and get_rtcl()

Signed-off-by: Christophe Leroy <christophe.le

powerpc: Remove __USE_RTC()

Now that PowerPC 601 is gone, __USE_RTC() is never true.

Remove it.

That also leads to removing get_rtc() and get_rtcl()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4757e1ed21fe1968c761ae081d1f3d790a9673f8.1601362098.git.christophe.leroy@csgroup.eu

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powerpc: Remove support for PowerPC 601

PowerPC 601 has been retired.

Remove all associated specific code.

CPU_FTRS_PPC601 has CPU_FTR_COHERENT_ICACHE and CPU_FTR_COMMON.

CPU_FTR_COMMON is alread

powerpc: Remove support for PowerPC 601

PowerPC 601 has been retired.

Remove all associated specific code.

CPU_FTRS_PPC601 has CPU_FTR_COHERENT_ICACHE and CPU_FTR_COMMON.

CPU_FTR_COMMON is already present via other CPU_FTRS.
None of the remaining CPU selects CPU_FTR_COHERENT_ICACHE.

So CPU_FTRS_PPC601 can be removed from the possible features,
hence can be removed completely.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/60b725d55e21beec3335175c20b77903ff98284f.1601362098.git.christophe.leroy@csgroup.eu

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powerpc: Drop old comment about CONFIG_POWER

There's a comment in time.h referring to CONFIG_POWER, which doesn't
exist. That confuses scripts/checkkconfigsymbols.py.

Presumably the comment was ref

powerpc: Drop old comment about CONFIG_POWER

There's a comment in time.h referring to CONFIG_POWER, which doesn't
exist. That confuses scripts/checkkconfigsymbols.py.

Presumably the comment was referring to a CONFIG_POWER vs CONFIG_PPC,
in which case for CONFIG_POWER we would #define __USE_RTC to 1. But
instead we have CONFIG_PPC_BOOK3S_601, and these days we have
IS_ENABLED().

So the comment is no longer relevant, drop it.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200724131728.1643966-9-mpe@ellerman.id.au

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powerpc/40x: Remove support for IBM 403GCX

CONFIG_403GCX is not user selectable and is not
selected by any platform.

Remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off

powerpc/40x: Remove support for IBM 403GCX

CONFIG_403GCX is not user selectable and is not
selected by any platform.

Remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/635f8f5ce9d1f761b3bd8dc3e8ddad500cea26c4.1590079968.git.christophe.leroy@csgroup.eu

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powerpc/64/sycall: Implement syscall entry/exit logic in C

System call entry and particularly exit code is beyond the limit of
what is reasonable to implement in asm.

This conversion moves all cond

powerpc/64/sycall: Implement syscall entry/exit logic in C

System call entry and particularly exit code is beyond the limit of
what is reasonable to implement in asm.

This conversion moves all conditional branches out of the asm code,
except for the case that all GPRs should be restored at exit.

Null syscall test is about 5% faster after this patch, because the
exit work is handled under local_irq_disable, and the hard mask and
pending interrupt replay is handled after that, which avoids games
with MSR.

mpe: Includes subsequent fixes from Nick:

This fixes 4 issues caught by TM selftests. First was a tm-syscall bug
that hit due to tabort_syscall being called after interrupts were
reconciled (in a subsequent patch), which led to interrupts being
enabled before tabort_syscall was called. Rather than going through an
un-reconciling interrupts for the return, I just go back to putting
the test early in asm, the C-ification of that wasn't a big win
anyway.

Second is the syscall return _TIF_USER_WORK_MASK check would go into
an infinite loop if _TIF_RESTORE_TM became set. The asm code uses
_TIF_USER_WORK_MASK to brach to slowpath which includes
restore_tm_state.

Third is system call return was not calling restore_tm_state, I missed
this completely (alhtough it's in the return from interrupt C
conversion because when the asm syscall code encountered problems it
would branch to the interrupt return code.

Fourth is MSR_VEC missing from restore_math, which was caught by
tm-unavailable selftest taking an unexpected facility unavailable
interrupt when testing VSX unavailble exception with MSR.FP=1
MSR.VEC=1. Fourth case also has a fixup in a subsequent patch.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200225173541.1549955-26-npiggin@gmail.com

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powerpc/64s/exception: Avoid touching the stack in hdecrementer

The hdec interrupt handler is reported to sometimes fire in Linux if
KVM leaves it pending after a guest exists. This is harmless, so

powerpc/64s/exception: Avoid touching the stack in hdecrementer

The hdec interrupt handler is reported to sometimes fire in Linux if
KVM leaves it pending after a guest exists. This is harmless, so there
is a no-op handler for it.

The interrupt handler currently uses the regular kernel stack. Change
this to avoid touching the stack entirely.

This should be the last place where the regular Linux stack can be
accessed with asynchronous interrupts (including PMI) soft-masked.
It might be possible to take advantage of this invariant, e.g., to
context switch the kernel stack SLB entry without clearing MSR[EE].

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200225173541.1549955-17-npiggin@gmail.com

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powerpc/32s: drop CPU_FTR_USE_RTC feature

CPU_FTR_USE_RTC feature only applies to powerpc601.

Drop this feature and replace it with tests on CONFIG_PPC_BOOK3S_601.

Signed-off-by: Christophe Leroy

powerpc/32s: drop CPU_FTR_USE_RTC feature

CPU_FTR_USE_RTC feature only applies to powerpc601.

Drop this feature and replace it with tests on CONFIG_PPC_BOOK3S_601.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/170411e2360861f4a95c21faad43519a08bc4040.1566834712.git.christophe.leroy@c-s.fr

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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 th

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>

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powerpc/hmi: Fix kernel hang when TB is in error state.

On TOD/TB errors timebase register stops/freezes until HMI error recovery
gets TOD/TB back into running state. On successful recovery, TB star

powerpc/hmi: Fix kernel hang when TB is in error state.

On TOD/TB errors timebase register stops/freezes until HMI error recovery
gets TOD/TB back into running state. On successful recovery, TB starts
running again and udelay() that relies on TB value continues to function
properly. But in case when HMI fails to recover from TOD/TB errors, the
TB register stay freezed. With TB not running the __delay() function
keeps looping and never return. If __delay() is called while in panic
path then system hangs and never reboots after panic.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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