kernel/linux.git/arch/powerpc/include/asm/time.h, branch linux-5.9.y

powerpc: Drop old comment about CONFIG_POWER

2020-07-29T11:08:27+00:00

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 Link: https://lore.kernel.org/r/20200724131728.1643966-9-mpe@ellerman.id.au

powerpc/40x: Remove support for IBM 403GCX

2020-05-28T13:24:35+00:00

CONFIG_403GCX is not user selectable and is not selected by any platform. Remove it. Signed-off-by: Christophe Leroy Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/635f8f5ce9d1f761b3bd8dc3e8ddad500cea26c4.1590079968.git.christophe.leroy@csgroup.eu

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

2020-04-01T02:42:13+00:00

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 Signed-off-by: Michal Suchanek Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200225173541.1549955-26-npiggin@gmail.com

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

2020-04-01T02:42:12+00:00

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 Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200225173541.1549955-17-npiggin@gmail.com

powerpc/32s: drop CPU_FTR_USE_RTC feature

2019-08-28T13:19:33+00:00

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 Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/170411e2360861f4a95c21faad43519a08bc4040.1566834712.git.christophe.leroy@c-s.fr

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

2019-05-30T18:26:32+00:00

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 Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

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

2019-05-02T16:54:57+00:00

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 Signed-off-by: Michael Ellerman

powerpc: change CONFIG_6xx to CONFIG_PPC_BOOK3S_32

2018-11-26T11:33:37+00:00

Today we have: config PPC_BOOK3S_32 bool "512x/52xx/6xx/7xx/74xx/82xx/83xx/86xx" [depends on PPC32 within a choice] config PPC_BOOK3S def_bool y depends on PPC_BOOK3S_32 || PPC_BOOK3S_64 config 6xx def_bool y depends on PPC32 && PPC_BOOK3S 6xx is therefore redundant with PPC_BOOK3S_32. In order to make the code clearer, lets use preferably PPC_BOOK3S_32. This will allow to remove CONFIG_6xx in a later patch. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman

powerpc: remove unused to_tm() helper

2018-06-03T10:43:34+00:00

to_tm() is now completely unused, the only reference being in the _dump_time() helper that is also unused. This removes both, leaving the rest of the powerpc RTC code y2038 safe to as far as the hardware supports. Signed-off-by: Arnd Bergmann Signed-off-by: Michael Ellerman

powerpc: generic clockevents broadcast receiver call tick_receive_broadcast

2018-06-03T10:40:27+00:00

The broadcast tick recipient can call tick_receive_broadcast rather than re-running the full timer interrupt. It does not have to check for the next event time, because the sender already determined the timer has expired. It does not have to test irq_work_pending, because that's a direct decrementer interrupt and does not go through the clock events subsystem. And it does not have to read PURR because that was removed with the previous patch. This results in no code size change, but both the decrementer and broadcast path lengths are reduced. Cc: Srivatsa S. Bhat Cc: Preeti U Murthy Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman