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2019-09-24powerpc/mm: Fixup tlbie vs mtpidr/mtlpidr ordering issue on POWER9Aneesh Kumar K.V1-0/+2
On POWER9, under some circumstances, a broadcast TLB invalidation will fail to invalidate the ERAT cache on some threads when there are parallel mtpidr/mtlpidr happening on other threads of the same core. This can cause stores to continue to go to a page after it's unmapped. The workaround is to force an ERAT flush using PID=0 or LPID=0 tlbie flush. This additional TLB flush will cause the ERAT cache invalidation. Since we are using PID=0 or LPID=0, we don't get filtered out by the TLB snoop filtering logic. We need to still follow this up with another tlbie to take care of store vs tlbie ordering issue explained in commit: a5d4b5891c2f ("powerpc/mm: Fixup tlbie vs store ordering issue on POWER9"). The presence of ERAT cache implies we can still get new stores and they may miss store queue marking flush. Cc: stable@vger.kernel.org Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190924035254.24612-3-aneesh.kumar@linux.ibm.com
2019-09-24powerpc/book3s64/radix: Rename CPU_FTR_P9_TLBIE_BUG feature flagAneesh Kumar K.V1-3/+3
Rename the #define to indicate this is related to store vs tlbie ordering issue. In the next patch, we will be adding another feature flag that is used to handles ERAT flush vs tlbie ordering issue. Fixes: a5d4b5891c2f ("powerpc/mm: Fixup tlbie vs store ordering issue on POWER9") Cc: stable@vger.kernel.org # v4.16+ Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190924035254.24612-2-aneesh.kumar@linux.ibm.com
2019-09-24powerpc/book3s64/mm: Don't do tlbie fixup for some hardware revisionsAneesh Kumar K.V1-2/+28
The store ordering vs tlbie issue mentioned in commit a5d4b5891c2f ("powerpc/mm: Fixup tlbie vs store ordering issue on POWER9") is fixed for Nimbus 2.3 and Cumulus 1.3 revisions. We don't need to apply the fixup if we are running on them We can only do this on PowerNV. On pseries guest with KVM we still don't support redoing the feature fixup after migration. So we should be enabling all the workarounds needed, because whe can possibly migrate between DD 2.3 and DD 2.2 Fixes: a5d4b5891c2f ("powerpc/mm: Fixup tlbie vs store ordering issue on POWER9") Cc: stable@vger.kernel.org # v4.16+ Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190924035254.24612-1-aneesh.kumar@linux.ibm.com
2019-09-21powerpc/64s: Set reserved PCR bitsJordan Niethe1-1/+2
Currently the reserved bits of the Processor Compatibility Register (PCR) are cleared as per the Programming Note in Section 1.3.3 of version 3.0B of the Power ISA. This causes all new architecture features to be made available when running on newer processors with new architecture features added to the PCR as bits must be set to disable a given feature. For example to disable new features added as part of Version 2.07 of the ISA the corresponding bit in the PCR needs to be set. As new processor features generally require explicit kernel support they should be disabled until such support is implemented. Therefore kernels should set all unknown/reserved bits in the PCR such that any new architecture features which the kernel does not currently know about get disabled. An update is planned to the ISA to clarify that the PCR is an exception to the Programming Note on reserved bits in Section 1.3.3. Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Tested-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190917004605.22471-2-alistair@popple.id.au
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 191Thomas Gleixner1-1/+1
Based on 1 normalized pattern(s): licensed under gplv2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 99 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Steve Winslow <swinslow@gmail.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190528170027.163048684@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-12treewide: add checks for the return value of memblock_alloc*()Mike Rapoport1-0/+5
Add check for the return value of memblock_alloc*() functions and call panic() in case of error. The panic message repeats the one used by panicing memblock allocators with adjustment of parameters to include only relevant ones. The replacement was mostly automated with semantic patches like the one below with manual massaging of format strings. @@ expression ptr, size, align; @@ ptr = memblock_alloc(size, align); + if (!ptr) + panic("%s: Failed to allocate %lu bytes align=0x%lx\n", __func__, size, align); [anders.roxell@linaro.org: use '%pa' with 'phys_addr_t' type] Link: http://lkml.kernel.org/r/20190131161046.21886-1-anders.roxell@linaro.org [rppt@linux.ibm.com: fix format strings for panics after memblock_alloc] Link: http://lkml.kernel.org/r/1548950940-15145-1-git-send-email-rppt@linux.ibm.com [rppt@linux.ibm.com: don't panic if the allocation in sparse_buffer_init fails] Link: http://lkml.kernel.org/r/20190131074018.GD28876@rapoport-lnx [akpm@linux-foundation.org: fix xtensa printk warning] Link: http://lkml.kernel.org/r/1548057848-15136-20-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Reviewed-by: Guo Ren <ren_guo@c-sky.com> [c-sky] Acked-by: Paul Burton <paul.burton@mips.com> [MIPS] Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> [s390] Reviewed-by: Juergen Gross <jgross@suse.com> [Xen] Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa] Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Christoph Hellwig <hch@lst.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Dennis Zhou <dennis@kernel.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Mark Salter <msalter@redhat.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Petr Mladek <pmladek@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-12powerpc: use memblock functions returning virtual addressChristophe Leroy1-2/+1
Since only the virtual address of allocated blocks is used, lets use functions returning directly virtual address. Those functions have the advantage of also zeroing the block. [rppt@linux.ibm.com: powerpc: remove duplicated alloc_stack() function] Link: http://lkml.kernel.org/r/20190226064032.GA5873@rapoport-lnx [rppt@linux.ibm.com: updated error message in alloc_stack() to be more verbose] [rppt@linux.ibm.com: convereted several additional call sites ] Link: http://lkml.kernel.org/r/1548057848-15136-3-git-send-email-rppt@linux.ibm.com Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Guo Ren <ren_guo@c-sky.com> [c-sky] Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Juergen Gross <jgross@suse.com> [Xen] Cc: Mark Salter <msalter@redhat.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Paul Burton <paul.burton@mips.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-02-22powerpc/64s: Fix logic when handling unknown CPU featuresMichael Ellerman1-10/+7
In cpufeatures_process_feature(), if a provided CPU feature is unknown and enable_unknown is false, we erroneously print that the feature is being enabled and return true, even though no feature has been enabled, and may also set feature bits based on the last entry in the match table. Fix this so that we only set feature bits from the match table if we have actually enabled a feature from that table, and when failing to enable an unknown feature, always print the "not enabling" message and return false. Coincidentally, some older gccs (<GCC 7), when invoked with -fsanitize-coverage=trace-pc, cause a spurious uninitialised variable warning in this function: arch/powerpc/kernel/dt_cpu_ftrs.c: In function ‘cpufeatures_process_feature’: arch/powerpc/kernel/dt_cpu_ftrs.c:686:7: warning: ‘m’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (m->cpu_ftr_bit_mask) An upcoming patch will enable support for kcov, which requires this option. This patch avoids the warning. Fixes: 5a61ef74f269 ("powerpc/64s: Support new device tree binding for discovering CPU features") Reported-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> [ajd: add commit message] Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
2018-10-31memblock: rename memblock_alloc{_nid,_try_nid} to memblock_phys_alloc*Mike Rapoport1-3/+1
Make it explicit that the caller gets a physical address rather than a virtual one. This will also allow using meblock_alloc prefix for memblock allocations returning virtual address, which is done in the following patches. The conversion is done using the following semantic patch: @@ expression e1, e2, e3; @@ ( - memblock_alloc(e1, e2) + memblock_phys_alloc(e1, e2) | - memblock_alloc_nid(e1, e2, e3) + memblock_phys_alloc_nid(e1, e2, e3) | - memblock_alloc_try_nid(e1, e2, e3) + memblock_phys_alloc_try_nid(e1, e2, e3) ) Link: http://lkml.kernel.org/r/1536927045-23536-7-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-19Merge branch 'topic/ppc-kvm' into nextMichael Ellerman1-3/+1
Merge in some commits we're sharing with the KVM tree. I manually propagated the change from commit d3d4ffaae439 ("powerpc/powernv/ioda2: Reduce upper limit for DMA window size") into pci-ioda-tce.c. Conflicts: arch/powerpc/include/asm/cputable.h arch/powerpc/platforms/powernv/pci-ioda.c arch/powerpc/platforms/powernv/pci.h
2018-07-16powerpc/64s: Remove POWER9 DD1 supportNicholas Piggin1-3/+1
POWER9 DD1 was never a product. It is no longer supported by upstream firmware, and it is not effectively supported in Linux due to lack of testing. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> [mpe: Remove arch_make_huge_pte() entirely] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-19powerpc/64s: Fix DT CPU features Power9 DD2.1 logicMichael Ellerman1-1/+2
In the device tree CPU features quirk code we want to set CPU_FTR_POWER9_DD2_1 on all Power9s that aren't DD2.0 or earlier. But we got the logic wrong and instead set it on all CPUs that aren't Power9 DD2.0 or earlier, ie. including Power8. Fix it by making sure we're on a Power9. This isn't a bug in practice because the only code that checks the feature is Power9 only to begin with. But we'll backport it anyway to avoid confusion. Fixes: 9e9626ed3a4a ("powerpc/64s: Fix POWER9 DD2.2 and above in DT CPU features") Cc: stable@vger.kernel.org # v4.17+ Reported-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc: Add TIDR CPU feature for POWER9Alastair D'Silva1-0/+1
This patch adds a CPU feature bit to show whether the CPU has the TIDR register available, enabling as_notify/wait in userspace. Signed-off-by: Alastair D'Silva <alastair@d-silva.org> Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-18powerpc/64s: Clear PCR on bootMichael Neuling1-0/+1
Clear the PCR (Processor Compatibility Register) on boot to ensure we are not running in a compatibility mode. We've seen this cause problems when a crash (and kdump) occurs while running compat mode guests. The kdump kernel then runs with the PCR set and causes problems. The symptom in the kdump kernel (also seen in petitboot after fast-reboot) is early userspace programs taking sigills on newer instructions (seen in libc). Signed-off-by: Michael Neuling <mikey@neuling.org> Cc: stable@vger.kernel.org Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-13powerpc/64s: Fix CPU_FTRS_ALWAYS vs DT CPU featuresMichael Ellerman1-13/+1
The cpu_has_feature() mechanism has an optimisation where at build time we construct a mask of the CPU feature bits that will always be true for the given .config, based on the platform/bitness/etc. that we are building for. That is incompatible with DT CPU features, where the set of CPU features is dependent on feature flags that are given to us by firmware. The result is that some feature bits can not be *disabled* by DT CPU features. Or more accurately, they can be disabled but they will still appear in the ALWAYS mask, meaning cpu_has_feature() will always return true for them. In the past this hasn't really been a problem because on Book3S 64 (where we support DT CPU features), the set of ALWAYS bits has been very small. That was because we always built for POWER4 and later, meaning the set of common bits was small. The only bit that could be cleared by DT CPU features that was also in the ALWAYS mask was CPU_FTR_NODSISRALIGN, and that was only used in the alignment handler to create a fake DSISR. That code was itself deleted in 31bfdb036f12 ("powerpc: Use instruction emulation infrastructure to handle alignment faults") (Sep 2017). However the set of ALWAYS features changed with the recent commit db5ae1c155af ("powerpc/64s: Refine feature sets for little endian builds") which restricted the set of feature flags when building little endian to Power7 or later. That caused the ALWAYS mask to become much larger for little endian builds. The result is that the following feature bits can currently not be *disabled* by DT CPU features: CPU_FTR_REAL_LE, CPU_FTR_MMCRA, CPU_FTR_CTRL, CPU_FTR_SMT, CPU_FTR_PURR, CPU_FTR_SPURR, CPU_FTR_DSCR, CPU_FTR_PKEY, CPU_FTR_VMX_COPY, CPU_FTR_CFAR, CPU_FTR_HAS_PPR. To fix it we need to mask the set of ALWAYS features with the base set of DT CPU features, ie. the features that are always enabled by DT CPU features. That way there are no bits in the ALWAYS mask that are not also always set by DT CPU features. Fixes: db5ae1c155af ("powerpc/64s: Refine feature sets for little endian builds") Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-05powerpc/64s: Fix pkey support in dt_cpu_ftrs, add CPU_FTR_PKEY bitNicholas Piggin1-0/+7
The pkey code added a CPU_FTR_PKEY bit, but did not add it to the dt_cpu_ftrs feature set. Although capability is supported by all processors in the base dt_cpu_ftrs set for 64s, it's a significant and sufficiently well defined feature to make it optional. So add it as a quirk for now, which can be versioned out then controlled by the firmware (once dt_cpu_ftrs gains versioning support). Fixes: cf43d3b26452 ("powerpc: Enable pkey subsystem") Cc: stable@vger.kernel.org # v4.16+ Cc: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-05powerpc/64s: Fix dt_cpu_ftrs to have restore_cpu clear unwanted LPCR bitsNicholas Piggin1-3/+9
Presently the dt_cpu_ftrs restore_cpu will only add bits to the LPCR for secondaries, but some bits must be removed (e.g., UPRT for HPT). Not clearing these bits on secondaries causes checkstops when booting with disable_radix. restore_cpu can not just set LPCR, because it is also called by the idle wakeup code which relies on opal_slw_set_reg to restore the value of LPCR, at least on P8 which does not save LPCR to stack in the idle code. Fix this by including a mask of bits to clear from LPCR as well, which is used by restore_cpu. This is a little messy now, but it's a minimal fix that can be backported. Longer term, the idle SPR save/restore code can be reworked to completely avoid calls to restore_cpu, then restore_cpu would be able to unconditionally set LPCR to match boot processor environment. Fixes: 5a61ef74f269f ("powerpc/64s: Support new device tree binding for discovering CPU features") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01powerpc/64s: Fix POWER9 DD2.2 and above in DT CPU featuresNicholas Piggin1-3/+8
The CPU_FTR_POWER9_DD2_1 flag is intended to be set for DD2.1 and above (which is what the cputable setup does). Fix DT CPU features quirk setup to match. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Merge with upstream changes] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-28Merge branch 'fixes' into nextMichael Ellerman1-1/+6
Merge our fixes branch from the 4.16 cycle. There were a number of important fixes merged, in particular some Power9 workarounds that we want in next for testing purposes. There's also been some conflicting changes in the CPU features code which are best merged and tested before going upstream.
2018-03-27powerpc: Disable DAWR on POWER9 via CPU feature quirkMichael Neuling1-0/+3
This disables the DAWR on all POWER9 CPUs via cpu feature quirk. Using the DAWR on POWER9 can cause xstops, hence we need to disable it. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-24powerpc: Add CPU feature bits for TM bug workarounds on POWER9 v2.2Paul Mackerras1-0/+5
This adds a CPU feature bit which is set for POWER9 "Nimbus" DD2.2 processors which will be used to enable the hypervisor to assist hardware with the handling of checkpointed register values while the CPU is in suspend state, in order to work around hardware bugs. The hardware assistance for these workarounds introduced a new hardware bug relating to the XER[SO] bit. We add a separate feature bit for this bug in case future chips fix it while still requiring the hypervisor assistance with suspend state. When the dt_cpu_ftrs subsystem is in use, the software assistance can be enabled using a "tm-suspend-hypervisor-assist" node in the device tree, and a "tm-suspend-xer-so-bug" node enables the workarounds for the XER[SO] bug. In the absence of such nodes, a quirk enables both for POWER9 "Nimbus" DD2.2 processors. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-24powerpc: Use feature bit for RTC presence rather than timebase presencePaul Mackerras1-2/+1
All PowerPC CPUs other than the original PPC601 have a timebase register rather than the "real-time clock" (RTC) register that the PPC601 (and the original POWER and POWER2 CPUs) had. Currently we have a CPU feature bit to indicate the presence of the timebase, but it makes more sense to use a bit to indicate the unusual situation rather than the common situation. This therefore defines a CPU_FTR_USE_RTC bit in place of the CPU_FTR_USE_TB bit, and arranges for it to be set on PPC601 systems. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-23powerpc/mm: Fixup tlbie vs store ordering issue on POWER9Aneesh Kumar K.V1-0/+3
On POWER9, under some circumstances, a broadcast TLB invalidation might complete before all previous stores have drained, potentially allowing stale stores from becoming visible after the invalidation. This works around it by doubling up those TLB invalidations which was verified by HW to be sufficient to close the risk window. This will be documented in a yet-to-be-published errata. Fixes: 1a472c9dba6b ("powerpc/mm/radix: Add tlbflush routines") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> [mpe: Enable the feature in the DT CPU features code for all Power9, rename the feature to CPU_FTR_P9_TLBIE_BUG per benh.] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-14powerpc/64s: Fix NULL AT_BASE_PLATFORM when using DT CPU featuresMichael Ellerman1-0/+3
When running virtualised the powerpc kernel is able to run the system in "compat mode" - which means the kernel and hardware are pretending to userspace that the CPU is an older version than it actually is. AT_BASE_PLATFORM is an AUXV entry that we export to userspace for use when we're running in that mode, which tells userspace the "platform" string for the real CPU version, as opposed to the faked version. Although we don't support compat mode when using DT CPU features, and arguably don't need to set AT_BASE_PLATFORM, the existing cputable based code always sets it even when we're running bare metal. That means the lack of AT_BASE_PLATFORM is a user-visible artifact of the fact that the kernel is using DT CPU features, which we don't want. So set it in the DT CPU features code also. This results in eg: $ LD_SHOW_AUXV=1 /bin/true | grep "AT_.*PLATFORM" AT_PLATFORM: power9 AT_BASE_PLATFORM:power9 Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
2018-01-18powerpc/64s: Improve local TLB flush for boot and MCE on POWER9Nicholas Piggin1-30/+0
There are several cases outside the normal address space management where a CPU's entire local TLB is to be flushed: 1. Booting the kernel, in case something has left stale entries in the TLB (e.g., kexec). 2. Machine check, to clean corrupted TLB entries. One other place where the TLB is flushed, is waking from deep idle states. The flush is a side-effect of calling ->cpu_restore with the intention of re-setting various SPRs. The flush itself is unnecessary because in the first case, the TLB should not acquire new corrupted TLB entries as part of sleep/wake (though they may be lost). This type of TLB flush is coded inflexibly, several times for each CPU type, and they have a number of problems with ISA v3.0B: - The current radix mode of the MMU is not taken into account, it is always done as a hash flushn For IS=2 (LPID-matching flush from host) and IS=3 with HV=0 (guest kernel flush), tlbie(l) is undefined if the R field does not match the current radix mode. - ISA v3.0B hash must flush the partition and process table caches as well. - ISA v3.0B radix must flush partition and process scoped translations, partition and process table caches, and also the page walk cache. So consolidate the flushing code and implement it in C and inline asm under the mm/ directory with the rest of the flush code. Add ISA v3.0B cases for radix and hash, and use the radix flush in radix environment. Provide a way for IS=2 (LPID flush) to specify the radix mode of the partition. Have KVM pass in the radix mode of the guest. Take out the flushes from early cputable/dt_cpu_ftrs detection hooks, and move it later in the boot process after, the MMU registers are set up and before relocation is first turned on. The TLB flush is no longer called when restoring from deep idle states. This was not be done as a separate step because booting secondaries uses the same cpu_restore as idle restore, which needs the TLB flush. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-22powerpc/64s: Fix Power9 DD2.1 logic in DT CPU featuresMichael Ellerman1-2/+2
I got the logic wrong in the DT CPU features code when I added the Power9 DD2.1 feature. We should be setting the bit if we detect a DD2.1, not clearing it if we detect a DD2.0. This code isn't actually exercised at the moment so nothing is actually broken. Fixes: 3ffa9d9e2a7c ("powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 feature") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-15powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 featureMichael Ellerman1-1/+1
Recently we added a CPU feature for Power9 DD2.0, to capture the fact that some workarounds are required only on Power9 DD1 and DD2.0 but not DD2.1 or later. Then in commit 9d2f510a66ec ("powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 ERAT workaround on DD2.1") and commit e3646330cf66 "powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 PMU workaround on DD2.1") we changed CPU_FTR_SECTIONs to check for DD1 or DD20, eg: BEGIN_FTR_SECTION PPC_INVALIDATE_ERAT END_FTR_SECTION_IFSET(CPU_FTR_POWER9_DD1 | CPU_FTR_POWER9_DD20) Unfortunately although this reads as "if set DD1 or DD2.0", the or is a bitwise or and actually generates a mask of both bits. The code that does the feature patching then checks that the value of the CPU features masked with that mask are equal to the mask. So the end result is we're checking for DD1 and DD20 being set, which never happens. Yes the API is terrible. Removing the ERAT workaround on DD2.0 results in random SEGVs, the system tends to boot, but things randomly die including sometimes dhclient, udev etc. To fix the problem and hopefully avoid it in future, we remove the DD2.0 CPU feature and instead add a DD2.1 (or later) feature. This allows us to easily express that the workarounds are required if DD2.1 is not set. At some point we will drop the DD1 workarounds entirely and some of this can be cleaned up. Fixes: 9d2f510a66ec ("powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 ERAT workaround on DD2.1") Fixes: e3646330cf66 ("powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 PMU workaround on DD2.1") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10Merge branch 'fixes' into nextMichael Ellerman1-2/+2
We have some dependencies & conflicts between patches in fixes and things to go in next, both in the radix TLB flush code and the IMC PMU driver. So merge fixes into next.
2017-11-06powerpc: add POWER9_DD20 featureNicholas Piggin1-0/+2
Cc: Michael Neuling <mikey@neuling.org> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06powerpc/64: Free up CPU_FTR_ICSWXMichael Ellerman1-1/+1
The last user of CPU_FTR_ICSWX was removed in commit 6ff4d3e96652 ("powerpc: Remove old unused icswx based coprocessor support"), so free the bit up for future use. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-03powerpc: Fix action argument for cpufeatures-based TLB flushJeremy Kerr1-2/+2
Commit 41d0c2ecde19 ("powerpc/powernv: Fix local TLB flush for boot and MCE on POWER9") introduced calls to __flush_tlb_power[89] from the cpufeatures code, specifying the number of sets to flush. However, these functions take an action argument, not a number of sets. This means we hit the BUG() in __flush_tlb_{206,300} when using cpufeatures-style configuration. This change passes TLB_INVAL_SCOPE_GLOBAL instead. Fixes: 41d0c2ecde19 ("powerpc/powernv: Fix local TLB flush for boot and MCE on POWER9") Cc: stable@vger.kernel.org # v4.13+ Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-11powerpc/powernv: Fix local TLB flush for boot and MCE on POWER9Nicholas Piggin1-14/+2
There are two cases outside the normal address space management where a CPU's local TLB is to be flushed: 1. Host boot; in case something has left stale entries in the TLB (e.g., kexec). 2. Machine check; to clean corrupted TLB entries. CPU state restore from deep idle states also flushes the TLB. However this seems to be a side effect of reusing the boot code to set CPU state, rather than a requirement itself. The current flushing has a number of problems with ISA v3.0B: - The current radix mode of the MMU is not taken into account. tlbiel is undefined if the R field does not match the current radix mode. - ISA v3.0B hash must flush the partition and process table caches. - ISA v3.0B radix must flush partition and process scoped translations, partition and process table caches, and also the page walk cache. Add POWER9 cases to handle these, with radix vs hash determined by the host MMU mode. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-01powerpc/64: Reclaim CPU_FTR_SUBCOREMichael Ellerman1-1/+0
We are running low on CPU feature bits, so we only want to use them when it's really necessary. CPU_FTR_SUBCORE is only used in one place, and only in C, so we don't need it in order to make asm patching work. It can only be set on "Power8" CPUs, which in practice means POWER8, POWER8E and POWER8NVL. There are no plans to implement it on future CPUs, but if there ever were we could retrofit it then. Although KVM uses subcores, it never looks at the CPU feature, it either looks at the ISA level or the threads_per_subcore value. So drop the CPU feature and do a PVR check instead. Drop the device tree "subcore" feature as we no longer support doing anything with it, and we will drop it from skiboot too. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-01powerpc/64s: Add dt_cpu_ftrs boot time setup optionNicholas Piggin1-9/+48
Provide a dt_cpu_ftrs= cmdline option to disable the dt_cpu_ftrs CPU feature discovery, and fall back to the "cputable" based version. Also allow control of advertising unknown features to userspace and with this parameter, and remove the clunky CONFIG option. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Add explicit early check of bootargs in dt_cpu_ftrs_init()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-09powerpc/64s: Support new device tree binding for discovering CPU featuresNicholas Piggin1-0/+1031
The ibm,powerpc-cpu-features device tree binding describes CPU features with ASCII names and extensible compatibility, privilege, and enablement metadata that allows improved flexibility and compatibility with new hardware. The interface is described in detail in ibm,powerpc-cpu-features.txt in this patch. Currently this code is not enabled by default, and there are no released firmwares that provide the binding. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>