summaryrefslogtreecommitdiff
path: root/arch/arc/include
AgeCommit message (Collapse)Author
2016-10-07Merge tag 'pci-v4.9-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: "Summary of PCI changes for the v4.9 merge window: Enumeration: - microblaze: Add multidomain support for procfs (Bharat Kumar Gogada) Resource management: - Ignore requested alignment for PROBE_ONLY and fixed resources (Yongji Xie) - Ignore requested alignment for VF BARs (Yongji Xie) PCI device hotplug: - Make core explicitly non-modular (Paul Gortmaker) PCIe native device hotplug: - Rename pcie_isr() locals for clarity (Bjorn Helgaas) - Return IRQ_NONE when we can't read interrupt status (Bjorn Helgaas) - Remove unnecessary guard (Bjorn Helgaas) - Clean up dmesg "Slot(%s)" messages (Bjorn Helgaas) - Remove useless pciehp_get_latch_status() calls (Bjorn Helgaas) - Clear attention LED on device add (Keith Busch) - Allow exclusive userspace control of indicators (Keith Busch) - Process all hotplug events before looking for new ones (Mayurkumar Patel) - Don't re-read Slot Status when queuing hotplug event (Mayurkumar Patel) - Don't re-read Slot Status when handling surprise event (Mayurkumar Patel) - Make explicitly non-modular (Paul Gortmaker) Power management: - Afford direct-complete to devices with non-standard PM (Lukas Wunner) - Query platform firmware for device power state (Lukas Wunner) - Recognize D3cold in pci_update_current_state() (Lukas Wunner) - Avoid unnecessary resume after direct-complete (Lukas Wunner) - Make explicitly non-modular (Paul Gortmaker) Virtualization: - Mark Atheros AR9580 to avoid bus reset (Maik Broemme) - Check for pci_setup_device() failure in pci_iov_add_virtfn() (Po Liu) MSI: - Enable PCI_MSI_IRQ_DOMAIN support for ARC (Joao Pinto) AER: - Remove aerdriver.nosourceid kernel parameter (Bjorn Helgaas) - Remove aerdriver.forceload kernel parameter (Bjorn Helgaas) - Fix aer_probe() kernel-doc comment (Cao jin) - Add bus flag to skip source ID matching (Jon Derrick) - Avoid memory allocation in interrupt handling path (Jon Derrick) - Cache capability position (Keith Busch) - Make explicitly non-modular (Paul Gortmaker) - Remove duplicate AER severity translation (Tyler Baicar) - Send correct severity to calculate AER severity (Tyler Baicar) Precision Time Measurement: - Add Precision Time Measurement (PTM) support (Jonathan Yong) - Add PTM clock granularity information (Bjorn Helgaas) - Add pci_enable_ptm() for drivers to enable PTM on endpoints (Bjorn Helgaas) Generic host bridge driver: - Fix pci_remap_iospace() failure path (Lorenzo Pieralisi) - Make explicitly non-modular (Paul Gortmaker) Altera host bridge driver: - Remove redundant platform_get_resource() return value check (Bjorn Helgaas) - Poll for link training status after retraining the link (Ley Foon Tan) - Rework config accessors for use without a struct pci_bus (Ley Foon Tan) - Move retrain from fixup to altera_pcie_host_init() (Ley Foon Tan) - Make MSI explicitly non-modular (Paul Gortmaker) - Make explicitly non-modular (Paul Gortmaker) - Relax device number checking to allow SR-IOV (Po Liu) ARM Versatile host bridge driver: - Fix pci_remap_iospace() failure path (Lorenzo Pieralisi) Axis ARTPEC-6 host bridge driver: - Drop __init from artpec6_add_pcie_port() (Niklas Cassel) Freescale i.MX6 host bridge driver: - Make explicitly non-modular (Paul Gortmaker) Intel VMD host bridge driver: - Add quirk for AER to ignore source ID (Jon Derrick) - Allocate IRQ lists with correct MSI-X count (Jon Derrick) - Convert to use pci_alloc_irq_vectors() API (Jon Derrick) - Eliminate vmd_vector member from list type (Jon Derrick) - Eliminate index member from IRQ list (Jon Derrick) - Synchronize with RCU freeing MSI IRQ descs (Keith Busch) - Request userspace control of PCIe hotplug indicators (Keith Busch) - Move VMD driver to drivers/pci/host (Keith Busch) Marvell Aardvark host bridge driver: - Fix pci_remap_iospace() failure path (Lorenzo Pieralisi) - Remove redundant dev_err call in advk_pcie_probe() (Wei Yongjun) Microsoft Hyper-V host bridge driver: - Use zero-length array in struct pci_packet (Dexuan Cui) - Use pci_function_description[0] in struct definitions (Dexuan Cui) - Remove the unused 'wrk' in struct hv_pcibus_device (Dexuan Cui) - Handle vmbus_sendpacket() failure in hv_compose_msi_msg() (Dexuan Cui) - Handle hv_pci_generic_compl() error case (Dexuan Cui) - Use list_move_tail() instead of list_del() + list_add_tail() (Wei Yongjun) NVIDIA Tegra host bridge driver: - Fix pci_remap_iospace() failure path (Lorenzo Pieralisi) - Remove redundant _data suffix (Thierry Reding) - Use of_device_get_match_data() (Thierry Reding) Qualcomm host bridge driver: - Make explicitly non-modular (Paul Gortmaker) Renesas R-Car host bridge driver: - Consolidate register space lookup and ioremap (Bjorn Helgaas) - Don't disable/unprepare clocks on prepare/enable failure (Geert Uytterhoeven) - Add multi-MSI support (Grigory Kletsko) - Fix pci_remap_iospace() failure path (Lorenzo Pieralisi) - Fix some checkpatch warnings (Sergei Shtylyov) - Try increasing PCIe link speed to 5 GT/s at boot (Sergei Shtylyov) Rockchip host bridge driver: - Add DT bindings for Rockchip PCIe controller (Shawn Lin) - Add Rockchip PCIe controller support (Shawn Lin) - Improve the deassert sequence of four reset pins (Shawn Lin) - Fix wrong transmitted FTS count (Shawn Lin) - Increase the Max Credit update interval (Rajat Jain) Samsung Exynos host bridge driver: - Make explicitly non-modular (Paul Gortmaker) ST Microelectronics SPEAr13xx host bridge driver: - Make explicitly non-modular (Paul Gortmaker) Synopsys DesignWare host bridge driver: - Return data directly from dw_pcie_readl_rc() (Bjorn Helgaas) - Exchange viewport of `MEMORYs' and `CFGs/IOs' (Dong Bo) - Check LTSSM training bit before deciding link is up (Jisheng Zhang) - Move link wait definitions to .c file (Joao Pinto) - Wait for iATU enable (Joao Pinto) - Add iATU Unroll feature (Joao Pinto) - Fix pci_remap_iospace() failure path (Lorenzo Pieralisi) - Make explicitly non-modular (Paul Gortmaker) - Relax device number checking to allow SR-IOV (Po Liu) - Keep viewport fixed for IO transaction if num_viewport > 2 (Pratyush Anand) - Remove redundant platform_get_resource() return value check (Wei Yongjun) TI DRA7xx host bridge driver: - Make explicitly non-modular (Paul Gortmaker) TI Keystone host bridge driver: - Propagate request_irq() failure (Wei Yongjun) Xilinx AXI host bridge driver: - Keep both legacy and MSI interrupt domain references (Bharat Kumar Gogada) - Clear interrupt register for invalid interrupt (Bharat Kumar Gogada) - Clear correct MSI set bit (Bharat Kumar Gogada) - Dispose of MSI virtual IRQ (Bharat Kumar Gogada) - Make explicitly non-modular (Paul Gortmaker) - Relax device number checking to allow SR-IOV (Po Liu) Xilinx NWL host bridge driver: - Expand error logging (Bharat Kumar Gogada) - Enable all MSI interrupts using MSI mask (Bharat Kumar Gogada) - Make explicitly non-modular (Paul Gortmaker) Miscellaneous: - Drop CONFIG_KEXEC_CORE ifdeffery (Lukas Wunner) - portdrv: Make explicitly non-modular (Paul Gortmaker) - Make DPC explicitly non-modular (Paul Gortmaker)" * tag 'pci-v4.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (105 commits) x86/PCI: VMD: Move VMD driver to drivers/pci/host PCI: rockchip: Fix wrong transmitted FTS count PCI: rockchip: Improve the deassert sequence of four reset pins PCI: rockchip: Increase the Max Credit update interval PCI: rcar: Try increasing PCIe link speed to 5 GT/s at boot PCI/AER: Fix aer_probe() kernel-doc comment PCI: Ignore requested alignment for VF BARs PCI: Ignore requested alignment for PROBE_ONLY and fixed resources PCI: Avoid unnecessary resume after direct-complete PCI: Recognize D3cold in pci_update_current_state() PCI: Query platform firmware for device power state PCI: Afford direct-complete to devices with non-standard PM PCI/AER: Cache capability position PCI/AER: Avoid memory allocation in interrupt handling path x86/PCI: VMD: Request userspace control of PCIe hotplug indicators PCI: pciehp: Allow exclusive userspace control of indicators ACPI / APEI: Send correct severity to calculate AER severity PCI/AER: Remove duplicate AER severity translation x86/PCI: VMD: Synchronize with RCU freeing MSI IRQ descs x86/PCI: VMD: Eliminate index member from IRQ list ...
2016-09-30ARCv2: fix local_save_flagsVineet Gupta
Commit d9676fa152c83b ("ARCv2: Enable LOCKDEP"), changed local_save_flags() to not return raw STATUS32 but encoded in the form such that it could be fed directly to CLRI/SETI instructions. However the STATUS32.E[] was not captured correctly as it corresponds to bits [4:1] in the register and not [3:0] Fixes: d9676fa152c83b ("ARCv2: Enable LOCKDEP") Cc: Evgeny Voevodin <evgeny.voevodin@intel.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-30ARC: dw2 unwind: add infrastructure for adding cfi pseudo ops to asmVineet Gupta
1. detect whether binutils supports the cfi pseudo ops 2. define conditional macros to generate the ops 3. define new ENTRY_CFI/END_CFI to annotate hand asm code. - Needed because we don't want to emit dwarf info in general ENTRY/END used by lowest level trap/exception/interrutp handlers as unwinder gets confused trying to unwind out of them. We want unwinder to instead stop when it hits onfo those routines - These provide minimal start/end cfi ops assuming routine doesn't touch stack memory/regs Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-30ARC: module: support R_ARC_32_PCREL relocationVineet Gupta
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-30arc: perf: Enable generic "cache-references" and "cache-misses" eventsAlexey Brodkin
We used to live with PERF_COUNT_HW_CACHE_REFERENCES and PERF_COUNT_HW_CACHE_REFERENCES not specified on ARC. Those events are actually aliases to 2 cache events that we do support and so this change sets "cache-reference" and "cache-misses" events in the same way as "L1-dcache-loads" and L1-dcache-load-misses. And while at it adding debug info for cache events as well as doing a subtle fix in HW events debug info - config value is much better represented by hex so we may see not only event index but as well other control bits set (if they exist). Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-30ARC: [plat-eznps] add missing atomic_fetch_xxx operationsNoam Camus
Build brekeage since last changes to generic atomic operations. Added couple of missing macros which are now mandatory Signed-off-by: Noam Camus <noamca@mellanox.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-30ARCv2: Implement atomic64 based on LLOCKD/SCONDD instructionsVineet Gupta
ARCv2 ISA provides 64-bit exclusive load/stores so use them to implement the 64-bit atomics and elide the spinlock based generic 64-bit atomics boot tested with atomic64 self-test (and GOD bless the person who wrote them, I realized my inline assmebly is sloppy as hell) Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-30ARCv2: Support dynamic peripheral address space in HS38 rel 3.0 coresVineet Gupta
HS release 3.0 provides for even more flexibility in specifying the volatile address space for mapping peripherals. With HS 2.1 @start was made flexible / programmable - with HS 3.0 even @end can be setup (vs. fixed to 0xFFFF_FFFF before). So add code to reflect that and while at it remove an unused struct defintion Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-14Merge branch 'uaccess-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull uaccess fixes from Al Viro: "Fixes for broken uaccess primitives - mostly lack of proper zeroing in copy_from_user()/get_user()/__get_user(), but for several architectures there's more (broken clear_user() on frv and strncpy_from_user() on hexagon)" * 'uaccess-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (28 commits) avr32: fix copy_from_user() microblaze: fix __get_user() microblaze: fix copy_from_user() m32r: fix __get_user() blackfin: fix copy_from_user() sparc32: fix copy_from_user() sh: fix copy_from_user() sh64: failing __get_user() should zero score: fix copy_from_user() and friends score: fix __get_user/get_user s390: get_user() should zero on failure ppc32: fix copy_from_user() parisc: fix copy_from_user() openrisc: fix copy_from_user() nios2: fix __get_user() nios2: copy_from_user() should zero the tail of destination mn10300: copy_from_user() should zero on access_ok() failure... mn10300: failing __get_user() and get_user() should zero mips: copy_from_user() must zero the destination on access_ok() failure ARC: uaccess: get_user to zero out dest in cause of fault ...
2016-09-13ARC: uaccess: get_user to zero out dest in cause of faultVineet Gupta
Al reported potential issue with ARC get_user() as it wasn't clearing out destination pointer in case of fault due to bad address etc. Verified using following | { | u32 bogus1 = 0xdeadbeef; | u64 bogus2 = 0xdead; | int rc1, rc2; | | pr_info("Orig values %x %llx\n", bogus1, bogus2); | rc1 = get_user(bogus1, (u32 __user *)0x40000000); | rc2 = get_user(bogus2, (u64 __user *)0x50000000); | pr_info("access %d %d, new values %x %llx\n", | rc1, rc2, bogus1, bogus2); | } | [ARCLinux]# insmod /mnt/kernel-module/qtn.ko | Orig values deadbeef dead | access -14 -14, new values 0 0 Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-06PCI/MSI: Enable PCI_MSI_IRQ_DOMAIN support for ARCJoao Pinto
Add ARC as an arch that supports PCI_MSI_IRQ_DOMAIN and add generation of msi.h in the ARC arch. Signed-off-by: Joao Pinto <jpinto@synopsys.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Vineet Gupta <vgupta@synopsys.com>
2016-08-19ARC: mm: fix build breakage with STRICT_MM_TYPECHECKSVineet Gupta
| CC mm/memory.o | In file included from ../mm/memory.c:53:0: | ../include/linux/pfn_t.h: In function ‘pfn_t_pte’: | ../include/linux/pfn_t.h:78:2: error: conversion to non-scalar type requested | return pfn_pte(pfn_t_to_pfn(pfn), pgprot); With STRICT_MM_TYPECHECKS pte_t is a struct and the offending code forces a cast which ends up shifting a struct and hence the gcc warning. Note that in recent past some of the arches (aarch64, s390) made STRICT_MM_TYPECHECKS default, but we don't for ARC as this leads to slightly worse generated code, given ARC ABI definition of returning structs (which pte_t would become) Quoting from ARC ABI... "Results of type struct are returned in a caller-supplied temporary variable whose address is passed in r0. For such functions, the arguments are shifted so that they are passed in r1 and up." So - struct to be returned would be allocated on stack requiring extra code at call sites - callee updates stack memory to facilitate the return (vs. simple MOV into return reg r0) Hence STRICT_MM_TYPECHECKS is not enabled by default for ARC Cc: <stable@vger.kernel.org> #4.4+ Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-08-19ARC: Support syscall ABI v4Vineet Gupta
The syscall ABI includes the gcc functional calling ABI since a syscall implies userland caller and kernel callee. The current gcc ABI (v3) for ARCv2 ISA required 64-bit data be passed in even-odd register pairs, (potentially punching reg holes when passing such values as args). This was partly driven by the fact that the double-word LDD/STD instructions in ARCv2 expect the register alignment and thus gcc forcing this avoids extra MOV at the cost of a few unused register (which we have plenty anyways). This however was rejected as part of upstreaming gcc port to HS. So the new ABI v4 doesn't enforce the even-odd reg restriction. Do note that for ARCompact ISA builds v3 and v4 are practically the same in terms of gcc code generation. In terms of change management, we infer the new ABI if gcc 6.x onwards is used for building the kernel. This also needs a stable backport to enable older kernels to work with new tools/user-space Cc: <stable@vger.kernel.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-08-19ARC: use correct offset in pt_regs for saving/restoring user mode r25Liav Rehana
User mode callee regs are explicitly collected before signal delivery or breakpoint trap. r25 is special for kernel as it serves as task pointer, so user mode value is clobbered very early. It is saved in pt_regs where generally only scratch (aka caller saved) regs are saved. The code to access the corresponding pt_regs location had a subtle bug as it was using load/store with scaling of offset, whereas the offset was already byte wise correct. So fix this by replacing LD.AS with a standard LD Cc: <stable@vger.kernel.org> Signed-off-by: Liav Rehana <liavr@mellanox.com> Reviewed-by: Alexey Brodkin <abrodkin@synopsys.com> [vgupta: rewrote title and commit log] Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-08-10ARC: Call trace_hardirqs_on() before enabling irqsDaniel Mentz
trace_hardirqs_on_caller() in lockdep.c expects to be called before, not after interrupts are actually enabled. The following comment in kernel/locking/lockdep.c substantiates this claim: " /* * We're enabling irqs and according to our state above irqs weren't * already enabled, yet we find the hardware thinks they are in fact * enabled.. someone messed up their IRQ state tracing. */ " An example can be found in include/linux/irqflags.h: do { trace_hardirqs_on(); raw_local_irq_enable(); } while (0) Without this change, we hit the following DEBUG_LOCKS_WARN_ON. [ 7.760000] ------------[ cut here ]------------ [ 7.760000] WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:2711 resume_user_mode_begin+0x48/0xf0 [ 7.770000] DEBUG_LOCKS_WARN_ON(!irqs_disabled()) [ 7.780000] Modules linked in: [ 7.780000] CPU: 0 PID: 1 Comm: init Not tainted 4.7.0-00003-gc668bb9-dirty #366 [ 7.790000] [ 7.790000] Stack Trace: [ 7.790000] arc_unwind_core.constprop.1+0xa4/0x118 [ 7.800000] warn_slowpath_fmt+0x72/0x158 [ 7.800000] resume_user_mode_begin+0x48/0xf0 [ 7.810000] ---[ end trace 6f6a7a8fae20d2f0 ]--- Signed-off-by: Daniel Mentz <danielmentz@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-07-29Merge tag 'arc-4.8-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc Pull ARC updates from Vineet Gupta: "Things have been calm here - nothing much except for a few fixes" * tag 'arc-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: ARC: mm: don't loose PTE_SPECIAL in pte_modify() ARC: dma: fix address translation in arc_dma_free ARC: typo fix in mm/ioremap.c ARC: fix linux-next build breakage
2016-07-28ARC: mm: don't loose PTE_SPECIAL in pte_modify()Vineet Gupta
LTP madvise05 was generating mm splat | [ARCLinux]# /sd/ltp/testcases/bin/madvise05 | BUG: Bad page map in process madvise05 pte:80e08211 pmd:9f7d4000 | page:9fdcfc90 count:1 mapcount:-1 mapping: (null) index:0x0 flags: 0x404(referenced|reserved) | page dumped because: bad pte | addr:200b8000 vm_flags:00000070 anon_vma: (null) mapping: (null) index:1005c | file: (null) fault: (null) mmap: (null) readpage: (null) | CPU: 2 PID: 6707 Comm: madvise05 And for newer kernels, the system was rendered unusable afterwards. The problem was mprotect->pte_modify() clearing PTE_SPECIAL (which is set to identify the special zero page wired to the pte). When pte was finally unmapped, special casing for zero page was not done, and instead it was treated as a "normal" page, tripping on the map counts etc. This fixes ARC STAR 9001053308 Cc: <stable@vger.kernel.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-07-25Merge branch 'locking-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "The locking tree was busier in this cycle than the usual pattern - a couple of major projects happened to coincide. The main changes are: - implement the atomic_fetch_{add,sub,and,or,xor}() API natively across all SMP architectures (Peter Zijlstra) - add atomic_fetch_{inc/dec}() as well, using the generic primitives (Davidlohr Bueso) - optimize various aspects of rwsems (Jason Low, Davidlohr Bueso, Waiman Long) - optimize smp_cond_load_acquire() on arm64 and implement LSE based atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() on arm64 (Will Deacon) - introduce smp_acquire__after_ctrl_dep() and fix various barrier mis-uses and bugs (Peter Zijlstra) - after discovering ancient spin_unlock_wait() barrier bugs in its implementation and usage, strengthen its semantics and update/fix usage sites (Peter Zijlstra) - optimize mutex_trylock() fastpath (Peter Zijlstra) - ... misc fixes and cleanups" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits) locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire() locking/static_keys: Fix non static symbol Sparse warning locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec() locking/atomic, arch/tile: Fix tilepro build locking/atomic, arch/m68k: Remove comment locking/atomic, arch/arc: Fix build locking/Documentation: Clarify limited control-dependency scope locking/atomic, arch/rwsem: Employ atomic_long_fetch_add() locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire() locking/atomic, arch/mips: Convert to _relaxed atomics locking/atomic, arch/alpha: Convert to _relaxed atomics locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions locking/atomic: Remove linux/atomic.h:atomic_fetch_or() locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() locking/atomic: Fix atomic64_relaxed() bits locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}() locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() ...
2016-06-25arc: get rid of superfluous __GFP_REPEATMichal Hocko
__GFP_REPEAT has a rather weak semantic but since it has been introduced around 2.6.12 it has been ignored for low order allocations. pte_alloc_one_kernel uses __get_order_pte but this is obviously always zero because BITS_FOR_PTE is not larger than 9 yet the page size is always larger than 4K. This means that this flag has never been actually useful here because it has always been used only for PAGE_ALLOC_COSTLY requests. Link: http://lkml.kernel.org/r/1464599699-30131-7-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-20locking/atomic, arch/arc: Fix buildPeter Zijlstra
Resolve conflict between commits: fbffe892e525 ("locking/atomic, arch/arc: Implement atomic_fetch_{add,sub,and,andnot,or,xor}()") and: ed6aefed726a ("Revert "ARCv2: spinlock/rwlock/atomics: Delayed retry of failed SCOND with exponential backoff"") Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nigel Topham <ntopham@synopsys.com> Cc: Noam Camus <noamc@ezchip.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: linux-kernel@vger.kernel.org Cc: linux-snps-arc@lists.infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-16locking/atomic: Remove linux/atomic.h:atomic_fetch_or()Peter Zijlstra
Since all architectures have this implemented now natively, remove this dead code. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-16locking/atomic, arch/arc: Implement atomic_fetch_{add,sub,and,andnot,or,xor}()Peter Zijlstra
Implement FETCH-OP atomic primitives, these are very similar to the existing OP-RETURN primitives we already have, except they return the value of the atomic variable _before_ modification. This is especially useful for irreversible operations -- such as bitops (because it becomes impossible to reconstruct the state prior to modification). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Vineet Gupta <vgupta@synopsys.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Noam Camus <noamc@ezchip.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-snps-arc@lists.infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-14locking/spinlock, arch: Update and fix spin_unlock_wait() implementationsPeter Zijlstra
This patch updates/fixes all spin_unlock_wait() implementations. The update is in semantics; where it previously was only a control dependency, we now upgrade to a full load-acquire to match the store-release from the spin_unlock() we waited on. This ensures that when spin_unlock_wait() returns, we're guaranteed to observe the full critical section we waited on. This fixes a number of spin_unlock_wait() users that (not unreasonably) rely on this. I also fixed a number of ticket lock versions to only wait on the current lock holder, instead of for a full unlock, as this is sufficient. Furthermore; again for ticket locks; I added an smp_rmb() in between the initial ticket load and the spin loop testing the current value because I could not convince myself the address dependency is sufficient, esp. if the loads are of different sizes. I'm more than happy to remove this smp_rmb() again if people are certain the address dependency does indeed work as expected. Note: PPC32 will be fixed independently Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: chris@zankel.net Cc: cmetcalf@mellanox.com Cc: davem@davemloft.net Cc: dhowells@redhat.com Cc: james.hogan@imgtec.com Cc: jejb@parisc-linux.org Cc: linux@armlinux.org.uk Cc: mpe@ellerman.id.au Cc: ralf@linux-mips.org Cc: realmz6@gmail.com Cc: rkuo@codeaurora.org Cc: rth@twiddle.net Cc: schwidefsky@de.ibm.com Cc: tony.luck@intel.com Cc: vgupta@synopsys.com Cc: ysato@users.sourceforge.jp Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-02Revert "ARCv2: spinlock/rwlock/atomics: Delayed retry of failed SCOND with ↵Vineet Gupta
exponential backoff" This reverts commit e78fdfef84be13a5c2b8276e12203cdf24778596. The issue was fixed in hardware in HS2.1C release and there are no known external users of affected RTL so revert the whole delayed retry series ! Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-06-02Revert "ARCv2: spinlock/rwlock: Reset retry delay when starting a new ↵Vineet Gupta
spin-wait cycle" This reverts commit b89aa12c177477e34caa722818536fb5d0bffd76. The issue was fixed in hardware in HS2.1C release and there are no known external users of affected RTL so revert the whole delayed retry series ! Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-06-02Revert "ARCv2: spinlock/rwlock/atomics: reduce 1 instruction in exponential ↵Vineet Gupta
backoff" This reverts commit 10971638701dedadb58c88ce4d31c9375b224ed6. The issue was fixed in hardware in HS2.1C release and there are no known external users of affected RTL - so revert thw whole delayed retry series ! Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-30Fix typosAndrea Gelmini
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-24Merge tag 'asm-generic-4.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic cleanup from Arnd Bergmann: "I have only one patch for asm-generic in this release, this one is from James Hogan and updates the generic system call table for renameat2 so we don't need to provide both renameat and renameat2 in newly added architectures" * tag 'asm-generic-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: Drop renameat syscall from default list
2016-05-20Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: - fsnotify fix - poll() timeout fix - a few scripts/ tweaks - debugobjects updates - the (small) ocfs2 queue - Minor fixes to kernel/padata.c - Maybe half of the MM queue * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (117 commits) mm, page_alloc: restore the original nodemask if the fast path allocation failed mm, page_alloc: uninline the bad page part of check_new_page() mm, page_alloc: don't duplicate code in free_pcp_prepare mm, page_alloc: defer debugging checks of pages allocated from the PCP mm, page_alloc: defer debugging checks of freed pages until a PCP drain cpuset: use static key better and convert to new API mm, page_alloc: inline pageblock lookup in page free fast paths mm, page_alloc: remove unnecessary variable from free_pcppages_bulk mm, page_alloc: pull out side effects from free_pages_check mm, page_alloc: un-inline the bad part of free_pages_check mm, page_alloc: check multiple page fields with a single branch mm, page_alloc: remove field from alloc_context mm, page_alloc: avoid looking up the first zone in a zonelist twice mm, page_alloc: shortcut watermark checks for order-0 pages mm, page_alloc: reduce cost of fair zone allocation policy retry mm, page_alloc: shorten the page allocator fast path mm, page_alloc: check once if a zone has isolated pageblocks mm, page_alloc: move __GFP_HARDWALL modifications out of the fastpath mm, page_alloc: simplify last cpupid reset mm, page_alloc: remove unnecessary initialisation from __alloc_pages_nodemask() ...
2016-05-20arch: fix has_transparent_hugepage()Hugh Dickins
I've just discovered that the useful-sounding has_transparent_hugepage() is actually an architecture-dependent minefield: on some arches it only builds if CONFIG_TRANSPARENT_HUGEPAGE=y, on others it's also there when not, but on some of those (arm and arm64) it then gives the wrong answer; and on mips alone it's marked __init, which would crash if called later (but so far it has not been called later). Straighten this out: make it available to all configs, with a sensible default in asm-generic/pgtable.h, removing its definitions from those arches (arc, arm, arm64, sparc, tile) which are served by the default, adding #define has_transparent_hugepage has_transparent_hugepage to those (mips, powerpc, s390, x86) which need to override the default at runtime, and removing the __init from mips (but maybe that kind of code should be avoided after init: set a static variable the first time it's called). Signed-off-by: Hugh Dickins <hughd@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andres Lagar-Cavilla <andreslc@google.com> Cc: Yang Shi <yang.shi@linaro.org> Cc: Ning Qu <quning@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc] Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [arch/s390] Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-13ARC: pae: STRICT_MM_TYPECHECKS was brokenVineet Gupta
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09ARC: [plat-eznps] Use dedicated COMMAND_LINE_SIZENoam Camus
The default 256 bytes sometimes is just not enough. We usually provide earlycon=... and console=... and ip=... All this and more may need more room. Signed-off-by: Noam Camus <noamc@ezchip.com> Acked-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09ARC: [plat-eznps] Use dedicated cpu_relax()Tal Zilcer
Since the CTOP is SMT hardware multi-threaded, we need to hint the HW that now will be a very good time to do a hardware thread context switching. This is done by issuing the schd.rw instruction (binary coded here so as to not require specific revision of GCC to build the kernel). sched.rw means that Thread becomes eligible for execution by the threads scheduler after all pending read/write transactions were completed. Implementing cpu_relax_lowlatency() with barrier() Since with current semantics of cpu_relax() it may take a while till yielded CPU will get back. Signed-off-by: Noam Camus <noamc@ezchip.com> Cc: Peter Zijlstra <peterz@infradead.org> Acked-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09ARC: [plat-eznps] Use dedicated identity auxiliary register.Noam Camus
With generic "identity" num of CPUs is limited to 256 (8 bit). We use our alternative AUX register GLOBAL_ID (12 bit). Now we can support up to 4096 CPUs. Signed-off-by: Noam Camus <noamc@ezchip.com>
2016-05-09ARC: [plat-eznps] Use dedicated SMP barriersNoam Camus
NPS device got 256 cores and each got 16 HW threads (SMT). We use EZchip dedicated ISA to trigger HW scheduler of the core that current HW thread belongs to. This scheduling makes sure that data beyond barrier is available to all HW threads in core and by that to all in device (4K). Signed-off-by: Noam Camus <noamc@ezchip.com> Cc: Peter Zijlstra <peterz@infradead.org>
2016-05-09ARC: [plat-eznps] Use dedicated atomic/bitops/cmpxchgNoam Camus
We need our own implementaions since we lack LLSC support. Our extended ISA provided with optimized solution for all 32bit operations we see in these three headers. Signed-off-by: Noam Camus <noamc@ezchip.com>
2016-05-09ARC: [plat-eznps] Use dedicated user stack topNoam Camus
NPS use special mapping right below TASK_SIZE. Hence we need to lower STACK_TOP so that user stack won't overlap NPS special mapping. Signed-off-by: Noam Camus <noamc@ezchip.com> Acked-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09ARC: rwlock: disable interrupts in !LLSC variantNoam Camus
If we hold rwlock and interrupt occures we may end up spinning on it for ever during softirq. Note that this lock is an internal lock and since the lock is free to be used from any context, the lock needs to be IRQ-safe. Below you may see an example for interrupt we get while nl_table_lock is holding its rw->lock_mutex and we spinned on it for ever. The concept for the fix was taken from SPARC. [2015-05-12 19:16:12] Stack Trace: [2015-05-12 19:16:12] arc_unwind_core+0xb8/0x11c [2015-05-12 19:16:12] dump_stack+0x68/0xac [2015-05-12 19:16:12] _raw_read_lock+0xa8/0xac [2015-05-12 19:16:12] netlink_broadcast_filtered+0x56/0x35c [2015-05-12 19:16:12] nlmsg_notify+0x42/0xa4 [2015-05-12 19:16:13] neigh_update+0x1fe/0x44c [2015-05-12 19:16:13] neigh_event_ns+0x40/0xa4 [2015-05-12 19:16:13] arp_process+0x46e/0x5a8 [2015-05-12 19:16:13] __netif_receive_skb_core+0x358/0x500 [2015-05-12 19:16:13] process_backlog+0x92/0x154 [2015-05-12 19:16:13] net_rx_action+0xb8/0x188 [2015-05-12 19:16:13] __do_softirq+0xda/0x1d8 [2015-05-12 19:16:14] irq_exit+0x8a/0x8c [2015-05-12 19:16:14] arch_do_IRQ+0x6c/0xa8 [2015-05-12 19:16:14] handle_interrupt_level1+0xe4/0xf0 Signed-off-by: Noam Camus <noamc@ezchip.com> Acked-by: Peter Zijlstra <peterz@infradead.org>
2016-05-09ARC: Make vmalloc size configurableNoam Camus
On ARC, lower 2G of address space is translated and used for - user vaddr space (region 0 to 5) - unused kernel-user gutter (region 6) - kernel vaddr space (region 7) where each region simply represents 256MB of address space. The kernel vaddr space of 256MB is used to implement vmalloc, modules So far this was enough, but not on EZChip system with 4K CPUs (given that per cpu mechanism uses vmalloc for allocating chunks) So allow VMALLOC_SIZE to be configurable by expanding down into the unused kernel-user gutter region which at default 256M was excessive anyways. Also use _BITUL() to fix a build error since PGDIR_SIZE cannot use "1UL" as called from assembly code in mm/tlbex.S Signed-off-by: Noam Camus <noamc@ezchip.com> [vgupta: rewrote changelog, debugged bootup crash due to int vs. hex] Acked-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09ARC: clean out UAPI byteorder.h clean off Kconfig symbolNoam Camus
UAPI header should not use Kconfig items Use __BIG_ENDIAN__ defined as a compiler intrinsic Signed-off-by: Noam Camus <noamc@ezchip.com> [vgupta: fix changelog] Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09ARC: RIP arc_{get|set}_core_freq() clk APIAlexey Brodkin
There are no more users of this - so RIP! Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> [vgupta: update changelog] Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09ARC: irq: export some IRQs againVineet Gupta
This will be needed for switching to linear irq domain as irq_create_mapping() called by intr code needs the IRQ numbers in addition to existing usage in mcip.c for requesting the irq Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09ARC: clockevent: DT based probeVineet Gupta
- timer frequency is derived from DT (no longer rely on top level DT "clock-frequency" probed early and exported by asm/clk.h) - TIMER0_IRQ need not be exported across arch code, confined to intc as it is property of same - Any failures in clockevent setup are considered pedantic and system panic()'s as there is no generic fallback (unlike clocksource where a jiffies based soft clocksource always exists) Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09ARC: clockevent: switch to cpu notifier for clockevent setupNoam Camus
ARC Timers so far have been handled as "legacy" w/o explicit description in DT. This poses challenge for newer platforms wanting to use them. This series will eventually help move timers over to DT. This patch does a small change of using a CPU notifier to set clockevent on non-boot CPUs. So explicit setup is done only on boot CPU (which will later be done by DT) Signed-off-by: Noam Camus <noamc@ezchip.com> [vgupta: broken off from a bigger patch] Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09ARC: opencode arc_request_percpu_irqVineet Gupta
- The idea is to remove the API usage since it has a subltle design flaw - relies on being called on cpu0 first. This is true for some early per cpu irqs such as TIMER/IPI, but not for late probed per cpu peripherals such a perf. And it's usage in perf has already bitten us once: see c6317bc7c5ab ("ARCv2: perf: Ensure perf intr gets enabled on all cores") where we ended up open coding it anyways - The seeming duplication will go away once we start using cpu notifier for timer setup Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-05ARC: support HIGHMEM even without PAE40Vineet Gupta
Initial HIGHMEM support on ARC was introduced for PAE40 where the low memory (0x8000_0000 based) and high memory (0x1_0000_0000) were physically contiguous. So CONFIG_FLATMEM sufficed (despite a peipheral hole in the middle, which wasted a bit of struct page memory, but things worked). However w/o PAE, highmem was not possible and we could only reach ~1.75GB of DDR. Now there is a use case to access ~4GB of DDR w/o PAE40 The idea is to have low memory at canonical 0x8000_0000 and highmem at 0 so enire 4GB address space is available for physical addressing This needs additional platform/interconnect mapping to convert the non contiguous physical addresses into linear bus adresses. From Linux point of view, non contiguous divide means FLATMEM no longer works and DISCONTIGMEM is needed to track the pfns in the 2 regions. This scheme would also work for PAE40, only better in that we don't waste struct page memory for the peripheral hole. The DT description will be something like memory { ... reg = <0x80000000 0x200000000 /* 512MB: lowmem */ 0x00000000 0x10000000>; /* 256MB: highmem */ } Signed-off-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-05ARC: Fix PAE40 boot failures due to PTE truncationVineet Gupta
So a benign looking cleanup which macro'ized PAGE_SHIFT shifts turned out to be bad (since it was done non-sensically across the board). It caused boot failures with PAE40 as forced cast to (unsigned long) from newly introduced virt_to_pfn() was causing truncatiion of the (long long) pte/paddr values. It is OK to use this in accessors dealing with kernel virtual address, pointers etc, but not for PTE values themelves. Fixes: cJ2ff5cf2735c ("ARC: mm: Use virt_to_pfn() for addr >> PAGE_SHIFT pattern) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-05ARC: Add missing io barriers to io{read,write}{16,32}be()Vineet Gupta
While reviewing a different change to asm-generic/io.h Arnd spotted that ARC ioread32 and ioread32be both of which come from asm-generic versions are not symmetrical in terms of calling the io barriers. generic ioread32 -> ARC readl() [ has barriers] generic ioread32be -> __be32_to_cpu(__raw_readl()) [ lacks barriers] While generic ioread32be is being remediated to call readl(), that involves a swab32(), causing double swaps on ioread32be() on Big Endian systems. So provide our versions of big endian IO accessors to ensure io barrier calls while also keeping them optimal Suggested-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: stable@vger.kernel.org [4.2+] Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-04asm-generic: Drop renameat syscall from default listJames Hogan
The newer renameat2 syscall provides all the functionality provided by the renameat syscall and adds flags, so future architectures won't need to include renameat. Therefore drop the renameat syscall from the generic syscall list unless __ARCH_WANT_RENAMEAT is defined by the architecture's unistd.h prior to including asm-generic/unistd.h, and adjust all architectures using the generic syscall list to define it so that no in-tree architectures are affected. Signed-off-by: James Hogan <james.hogan@imgtec.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Cc: linux-arch@vger.kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Mark Salter <msalter@redhat.com> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: linux-c6x-dev@linux-c6x.org Cc: Richard Kuo <rkuo@codeaurora.org> Cc: linux-hexagon@vger.kernel.org Cc: linux-metag@vger.kernel.org Cc: Jonas Bonn <jonas@southpole.se> Cc: linux@lists.openrisc.net Cc: Chen Liqin <liqin.linux@gmail.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ley Foon Tan <lftan@altera.com> Cc: nios2-dev@lists.rocketboards.org Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: uclinux-h8-devel@lists.sourceforge.jp Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2016-04-22ARCv2: Enable LOCKDEPEvgeny Voevodin
- The asm helpers for calling into irq tracer were missing - Add calls to above helpers in low level assembly entry code for ARCv2 - irq_save() uses CLRI to disable interrupts and returns the prev interrupt state (in STATUS32) in a specific encoding (and not the raw value of STATUS32). This is usable with SETI in irq_restore(). However save_flags() reads the raw value of STATUS32 which doesn't pair with irq_save/restore() and thus needs fixing. Signed-off-by: Evgeny Voevodin <evgeny.voevodin@intel.com> [vgupta: updated changelog and also added some comments] Signed-off-by: Vineet Gupta <vgupta@synopsys.com>