Commit Graph

111 Commits

Author SHA1 Message Date
Shadab Naseem
6bd5f11e49 arm: traps: emulate a MRC instruction reading CNTFRQ register
Emulate a MRC instruction reading CNTFRQ register.

Change-Id: I054121896d2173fc064aa75b4398178b04a701f7
Signed-off-by: Shadab Naseem <snaseem@codeaurora.org>
2020-01-27 13:58:51 +05:30
Neeraj Upadhyay
946bf463fe arm: traps: emulate a MRRC instruction reading CNTVCT register
Emulate CNTVCT access, so that userspace can get CNTVCT value,
if the direct counter read is disabled. Also, keep direct
access disabled by default for userspace.

Change-Id: I70263c129386314880cb28d1e561146ce62d52b8
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Cong Zhang <congzhan@codeaurora.org>
Signed-off-by: Shadab Naseem <snaseem@codeaurora.org>
2020-01-27 13:57:46 +05:30
Greg Hackmann
ecf58d041b clocksource: arch_timer: make virtual counter access configurable
Add a config option to support virtual counter access from userspace.

Change-Id: Ibdb1fd768b748002b90bfc165612c12c8311f8a2
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Venkata Narendra Kumar Gutta <vnkgutta@codeaurora.org>
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Cong Zhang <congzhan@codeaurora.org>
2020-01-24 14:44:20 +05:30
Marc Zyngier
0e72855e79 arm64: arch_timer: Add workaround for ARM erratum 1188873
When running on Cortex-A76, a timer access from an AArch32 EL0
task may end up with a corrupted value or register. The workaround for
this is to trap these accesses at EL1/EL2 and execute them there.

This only affects versions r0p0, r1p0 and r2p0 of the CPU.

Change-Id: If2026eff975725d41dc2f1630ab086f3cc7deea3
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Git-commit: 95b861a4a6d94f64d5242605569218160ebacdbe
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[neeraju@codeaurora: Resolve trivial merge conflicts.]
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
2019-05-20 19:57:24 -07:00
Ivaylo Georgiev
6f910c4e90 Merge android-4.19.31 (bb418a1) into msm-4.19
* refs/heads/tmp-bb418a1:
  Linux 4.19.31
  s390/setup: fix boot crash for machine without EDAT-1
  bcache: use (REQ_META|REQ_PRIO) to indicate bio for metadata
  KVM: nVMX: Ignore limit checks on VMX instructions using flat segments
  KVM: nVMX: Apply addr size mask to effective address for VMX instructions
  KVM: nVMX: Sign extend displacements of VMX instr's mem operands
  KVM: x86/mmu: Do not cache MMIO accesses while memslots are in flux
  KVM: x86/mmu: Detect MMIO generation wrap in any address space
  KVM: Call kvm_arch_memslots_updated() before updating memslots
  drm/amd/display: don't call dm_pp_ function from an fpu block
  drm/amd/powerplay: correct power reading on fiji
  drm/radeon/evergreen_cs: fix missing break in switch statement
  drm/fb-helper: generic: Fix drm_fbdev_client_restore()
  media: imx: csi: Stop upstream before disabling IDMA channel
  media: imx: csi: Disable CSI immediately after last EOF
  media: vimc: Add vimc-streamer for stream control
  media: uvcvideo: Avoid NULL pointer dereference at the end of streaming
  media: lgdt330x: fix lock status reporting
  media: imx: prpencvf: Stop upstream before disabling IDMA channel
  rcu: Do RCU GP kthread self-wakeup from softirq and interrupt
  tpm: Unify the send callback behaviour
  tpm/tpm_crb: Avoid unaligned reads in crb_recv()
  md: Fix failed allocation of md_register_thread
  perf intel-pt: Fix divide by zero when TSC is not available
  perf/x86/intel/uncore: Fix client IMC events return huge result
  perf intel-pt: Fix overlap calculation for padding
  perf auxtrace: Define auxtrace record alignment
  perf tools: Fix split_kallsyms_for_kcore() for trampoline symbols
  perf intel-pt: Fix CYC timestamp calculation after OVF
  x86/unwind/orc: Fix ORC unwind table alignment
  vt: perform safe console erase in the right order
  stable-kernel-rules.rst: add link to networking patch queue
  bcache: never writeback a discard operation
  PM / wakeup: Rework wakeup source timer cancellation
  svcrpc: fix UDP on servers with lots of threads
  NFSv4.1: Reinitialise sequence results before retransmitting a request
  nfsd: fix wrong check in write_v4_end_grace()
  nfsd: fix memory corruption caused by readdir
  nfsd: fix performance-limiting session calculation
  NFS: Don't recoalesce on error in nfs_pageio_complete_mirror()
  NFS: Fix an I/O request leakage in nfs_do_recoalesce
  NFS: Fix I/O request leakages
  cpcap-charger: generate events for userspace
  mfd: sm501: Fix potential NULL pointer dereference
  dm integrity: limit the rate of error messages
  dm: fix to_sector() for 32bit
  ipmi_si: fix use-after-free of resource->name
  arm64: KVM: Fix architecturally invalid reset value for FPEXC32_EL2
  arm64: debug: Ensure debug handlers check triggering exception level
  arm64: Fix HCR.TGE status for NMI contexts
  ARM: s3c24xx: Fix boolean expressions in osiris_dvs_notify
  powerpc/traps: Fix the message printed when stack overflows
  powerpc/traps: fix recoverability of machine check handling on book3s/32
  powerpc/hugetlb: Don't do runtime allocation of 16G pages in LPAR configuration
  powerpc/ptrace: Simplify vr_get/set() to avoid GCC warning
  powerpc: Fix 32-bit KVM-PR lockup and host crash with MacOS guest
  powerpc/powernv: Don't reprogram SLW image on every KVM guest entry/exit
  powerpc/83xx: Also save/restore SPRG4-7 during suspend
  powerpc/powernv: Make opal log only readable by root
  powerpc/wii: properly disable use of BATs when requested.
  powerpc/32: Clear on-stack exception marker upon exception return
  security/selinux: fix SECURITY_LSM_NATIVE_LABELS on reused superblock
  selinux: add the missing walk_size + len check in selinux_sctp_bind_connect
  jbd2: fix compile warning when using JBUFFER_TRACE
  jbd2: clear dirty flag when revoking a buffer from an older transaction
  serial: 8250_pci: Have ACCES cards that use the four port Pericom PI7C9X7954 chip use the pci_pericom_setup()
  serial: 8250_pci: Fix number of ports for ACCES serial cards
  serial: 8250_of: assume reg-shift of 2 for mrvl,mmp-uart
  serial: uartps: Fix stuck ISR if RX disabled with non-empty FIFO
  bpf: only test gso type on gso packets
  drm/i915: Relax mmap VMA check
  can: flexcan: FLEXCAN_IFLAG_MB: add () around macro argument
  gpio: pca953x: Fix dereference of irq data in shutdown
  media: i2c: ov5640: Fix post-reset delay
  i2c: tegra: fix maximum transfer size
  parport_pc: fix find_superio io compare code, should use equal test.
  intel_th: Don't reference unassigned outputs
  device property: Fix the length used in PROPERTY_ENTRY_STRING()
  kernel/sysctl.c: add missing range check in do_proc_dointvec_minmax_conv
  mm/memory.c: do_fault: avoid usage of stale vm_area_struct
  mm/vmalloc: fix size check for remap_vmalloc_range_partial()
  mm: hwpoison: fix thp split handing in soft_offline_in_use_page()
  dmaengine: usb-dmac: Make DMAC system sleep callbacks explicit
  usb: typec: tps6598x: handle block writes separately with plain-I2C adapters
  usb: chipidea: tegra: Fix missed ci_hdrc_remove_device()
  clk: ingenic: Fix doc of ingenic_cgu_div_info
  clk: ingenic: Fix round_rate misbehaving with non-integer dividers
  clk: samsung: exynos5: Fix kfree() of const memory on setting driver_override
  clk: samsung: exynos5: Fix possible NULL pointer exception on platform_device_alloc() failure
  clk: clk-twl6040: Fix imprecise external abort for pdmclk
  clk: uniphier: Fix update register for CPU-gear
  ext2: Fix underflow in ext2_max_size()
  cxl: Wrap iterations over afu slices inside 'afu_list_lock'
  IB/hfi1: Close race condition on user context disable and close
  PCI: dwc: skip MSI init if MSIs have been explicitly disabled
  PCI/DPC: Fix print AER status in DPC event handling
  PCI/ASPM: Use LTR if already enabled by platform
  ext4: fix crash during online resizing
  ext4: add mask of ext4 flags to swap
  ext4: update quota information while swapping boot loader inode
  ext4: cleanup pagecache before swap i_data
  ext4: fix check of inode in swap_inode_boot_loader
  cpufreq: pxa2xx: remove incorrect __init annotation
  cpufreq: tegra124: add missing of_node_put()
  cpufreq: kryo: Release OPP tables on module removal
  x86/kprobes: Prohibit probing on optprobe template code
  irqchip/brcmstb-l2: Use _irqsave locking variants in non-interrupt code
  irqchip/gic-v3-its: Avoid parsing _indirect_ twice for Device table
  libertas_tf: don't set URB_ZERO_PACKET on IN USB transfer
  soc: qcom: rpmh: Avoid accessing freed memory from batch API
  Btrfs: fix corruption reading shared and compressed extents after hole punching
  btrfs: ensure that a DUP or RAID1 block group has exactly two stripes
  Btrfs: setup a nofs context for memory allocation at __btrfs_set_acl
  Btrfs: setup a nofs context for memory allocation at btrfs_create_tree()
  m68k: Add -ffreestanding to CFLAGS
  ovl: Do not lose security.capability xattr over metadata file copy-up
  ovl: During copy up, first copy up data and then xattrs
  splice: don't merge into linked buffers
  fs/devpts: always delete dcache dentry-s in dput()
  scsi: qla2xxx: Fix LUN discovery if loop id is not assigned yet by firmware
  scsi: target/iscsi: Avoid iscsit_release_commands_from_conn() deadlock
  scsi: sd: Optimal I/O size should be a multiple of physical block size
  scsi: aacraid: Fix performance issue on logical drives
  scsi: virtio_scsi: don't send sc payload with tmfs
  s390/virtio: handle find on invalid queue gracefully
  s390/setup: fix early warning messages
  clocksource/drivers/arch_timer: Workaround for Allwinner A64 timer instability
  clocksource/drivers/exynos_mct: Clear timer interrupt when shutdown
  clocksource/drivers/exynos_mct: Move one-shot check from tick clear to ISR
  regulator: s2mpa01: Fix step values for some LDOs
  regulator: max77620: Initialize values for DT properties
  regulator: s2mps11: Fix steps for buck7, buck8 and LDO35
  spi: pxa2xx: Setup maximum supported DMA transfer length
  spi: ti-qspi: Fix mmap read when more than one CS in use
  netfilter: ipt_CLUSTERIP: fix warning unused variable cn
  mmc:fix a bug when max_discard is 0
  mmc: sdhci-esdhc-imx: fix HS400 timing issue
  ACPI / device_sysfs: Avoid OF modalias creation for removed device
  xen: fix dom0 boot on huge systems
  tracing/perf: Use strndup_user() instead of buggy open-coded version
  tracing: Do not free iter->trace in fail path of tracing_open_pipe()
  tracing: Use strncpy instead of memcpy for string keys in hist triggers
  CIFS: Fix read after write for files with read caching
  CIFS: Do not skip SMB2 message IDs on send failures
  CIFS: Do not reset lease state to NONE on lease break
  crypto: arm64/aes-ccm - fix bugs in non-NEON fallback routine
  crypto: arm64/aes-ccm - fix logical bug in AAD MAC handling
  crypto: x86/morus - fix handling chunked inputs and MAY_SLEEP
  crypto: x86/aesni-gcm - fix crash on empty plaintext
  crypto: x86/aegis - fix handling chunked inputs and MAY_SLEEP
  crypto: testmgr - skip crc32c context test for ahash algorithms
  crypto: skcipher - set CRYPTO_TFM_NEED_KEY if ->setkey() fails
  crypto: pcbc - remove bogus memcpy()s with src == dest
  crypto: morus - fix handling chunked inputs
  crypto: hash - set CRYPTO_TFM_NEED_KEY if ->setkey() fails
  crypto: arm64/crct10dif - revert to C code for short inputs
  crypto: arm64/aes-neonbs - fix returning final keystream block
  crypto: arm/crct10dif - revert to C code for short inputs
  crypto: aegis - fix handling chunked inputs
  crypto: aead - set CRYPTO_TFM_NEED_KEY if ->setkey() fails
  fix cgroup_do_mount() handling of failure exits
  libnvdimm: Fix altmap reservation size calculation
  libnvdimm/pmem: Honor force_raw for legacy pmem regions
  libnvdimm, pfn: Fix over-trim in trim_pfn_device()
  libnvdimm/label: Clear 'updating' flag after label-set update
  nfit/ars: Attempt short-ARS even in the no_init_ars case
  nfit/ars: Attempt a short-ARS whenever the ARS state is idle at boot
  acpi/nfit: Fix bus command validation
  nfit: acpi_nfit_ctl(): Check out_obj->type in the right place
  stm class: Prevent division by zero
  tmpfs: fix uninitialized return value in shmem_link
  selftests: fib_tests: sleep after changing carrier. again.
  net: set static variable an initial value in atl2_probe()
  bnxt_en: Wait longer for the firmware message response to complete.
  bnxt_en: Fix typo in firmware message timeout logic.
  nfp: bpf: fix ALU32 high bits clearance bug
  nfp: bpf: fix code-gen bug on BPF_ALU | BPF_XOR | BPF_K
  net: thunderx: add nicvf_send_msg_to_pf result check for set_rx_mode_task
  net: thunderx: make CFG_DONE message to run through generic send-ack sequence
  bpf, lpm: fix lookup bug in map_delete_elem
  mac80211_hwsim: propagate genlmsg_reply return code
  phonet: fix building with clang
  ARCv2: don't assume core 0x54 has dual issue
  ARCv2: support manual regfile save on interrupts
  ARC: uacces: remove lp_start, lp_end from clobber list
  ARCv2: lib: memcpy: fix doing prefetchw outside of buffer
  ixgbe: fix older devices that do not support IXGBE_MRQC_L3L4TXSWEN
  tmpfs: fix link accounting when a tmpfile is linked in
  mm: handle lru_add_drain_all for UP properly
  net: marvell: mvneta: fix DMA debug warning
  ARM: tegra: Restore DT ABI on Tegra124 Chromebooks
  arm64: Relax GIC version check during early boot
  ARM: dts: armada-xp: fix Armada XP boards NAND description
  qed: Fix iWARP syn packet mac address validation.
  qed: Fix iWARP buffer size provided for syn packet processing.
  ASoC: topology: free created components in tplg load error
  mailbox: bcm-flexrm-mailbox: Fix FlexRM ring flush timeout issue
  xfrm: Fix inbound traffic via XFRM interfaces across network namespaces
  net: mv643xx_eth: disable clk on error path in mv643xx_eth_shared_probe()
  qmi_wwan: apply SET_DTR quirk to Sierra WP7607
  pinctrl: meson: meson8b: fix the sdxc_a data 1..3 pins
  net: dsa: bcm_sf2: Do not assume DSA master supports WoL
  net: systemport: Fix reception of BPDUs
  scsi: libiscsi: Fix race between iscsi_xmit_task and iscsi_complete_task
  keys: Fix dependency loop between construction record and auth key
  assoc_array: Fix shortcut creation
  ARM: 8835/1: dma-mapping: Clear DMA ops on teardown
  af_key: unconditionally clone on broadcast
  bpf: fix lockdep false positive in stackmap
  bpf: only adjust gso_size on bytestream protocols
  ARM: 8824/1: fix a migrating irq bug when hotplug cpu
  esp: Skip TX bytes accounting when sending from a request socket
  clk: sunxi: A31: Fix wrong AHB gate number
  kallsyms: Handle too long symbols in kallsyms.c
  clk: sunxi-ng: v3s: Fix TCON reset de-assert bit
  Input: st-keyscan - fix potential zalloc NULL dereference
  auxdisplay: ht16k33: fix potential user-after-free on module unload
  i2c: bcm2835: Clear current buffer pointers and counts after a transfer
  i2c: cadence: Fix the hold bit setting
  net: hns: Fix object reference leaks in hns_dsaf_roce_reset()
  mm: page_alloc: fix ref bias in page_frag_alloc() for 1-byte allocs
  x86/CPU: Add Icelake model number
  net: dsa: bcm_sf2: potential array overflow in bcm_sf2_sw_suspend()
  scsi: qla2xxx: Fix panic from use after free in qla2x00_async_tm_cmd
  Revert "mm: use early_pfn_to_nid in page_ext_init"
  mm/gup: fix gup_pmd_range() for dax
  NFS: Don't use page_file_mapping after removing the page
  xprtrdma: Make sure Send CQ is allocated on an existing compvec
  floppy: check_events callback should not return a negative number
  ipvs: fix dependency on nf_defrag_ipv6
  blk-mq: insert rq with DONTPREP to hctx dispatch list when requeue
  netfilter: compat: initialize all fields in xt_init
  mac80211: Fix Tx aggregation session tear down with ITXQs
  mac80211: call drv_ibss_join() on restart
  Input: matrix_keypad - use flush_delayed_work()
  Input: ps2-gpio - flush TX work when closing port
  Input: cap11xx - switch to using set_brightness_blocking()
  ARM: OMAP2+: fix lack of timer interrupts on CPU1 after hotplug
  ASoC: samsung: Prevent clk_get_rate() calls in atomic context
  KVM: arm64: Forbid kprobing of the VHE world-switch code
  KVM: arm/arm64: vgic: Always initialize the group of private IRQs
  arm/arm64: KVM: Don't panic on failure to properly reset system registers
  arm/arm64: KVM: Allow a VCPU to fully reset itself
  KVM: arm/arm64: Reset the VCPU without preemption and vcpu state loaded
  ASoC: rsnd: fixup rsnd_ssi_master_clk_start() user count check
  ASoC: dapm: fix out-of-bounds accesses to DAPM lookup tables
  ARM: OMAP2+: Variable "reg" in function omap4_dsi_mux_pads() could be uninitialized
  ARM: dts: Configure clock parent for pwm vibra
  Input: pwm-vibra - stop regulator after disabling pwm, not before
  Input: pwm-vibra - prevent unbalanced regulator
  s390/dasd: fix using offset into zero size array error
  arm64: dts: rockchip: fix graph_port warning on rk3399 bob kevin and excavator
  KVM: arm/arm64: vgic: Make vgic_dist->lpi_list_lock a raw_spinlock
  clocksource: timer-ti-dm: Fix pwm dmtimer usage of fck reparenting
  ASoC: rt5682: Correct the setting while select ASRC clk for AD/DA filter
  gpu: ipu-v3: Fix CSI offsets for imx53
  drm/imx: imx-ldb: add missing of_node_puts
  gpu: ipu-v3: Fix i.MX51 CSI control registers offset
  drm/imx: ignore plane updates on disabled crtcs
  crypto: rockchip - update new iv to device in multiple operations
  crypto: rockchip - fix scatterlist nents error
  crypto: ahash - fix another early termination in hash walk
  crypto: cfb - remove bogus memcpy() with src == dest
  crypto: cfb - add missing 'chunksize' property
  crypto: ccree - don't copy zero size ciphertext
  crypto: ccree - unmap buffer before copying IV
  crypto: ccree - fix free of unallocated mlli buffer
  crypto: caam - fix DMA mapping of stack memory
  crypto: caam - fixed handling of sg list
  crypto: ccree - fix missing break in switch statement
  crypto: caam - fix hash context DMA unmap size
  stm class: Fix an endless loop in channel allocation
  mei: bus: move hw module get/put to probe/release
  mei: hbm: clean the feature flags on link reset
  iio: adc: exynos-adc: Fix NULL pointer exception on unbind
  ASoC: codecs: pcm186x: Fix energysense SLEEP bit
  ASoC: codecs: pcm186x: fix wrong usage of DECLARE_TLV_DB_SCALE()
  ASoC: fsl_esai: fix register setting issue in RIGHT_J mode
  9p/net: fix memory leak in p9_client_create
  9p: use inode->i_lock to protect i_size_write() under 32-bit
  media: videobuf2-v4l2: drop WARN_ON in vb2_warn_zero_bytesused()
  ANDROID: cuttlefish_defconfig: Enable CONFIG_INPUT_MOUSEDEV
  FROMLIST: psi: introduce psi monitor
  FROMLIST: refactor header includes to allow kthread.h inclusion in psi_types.h
  FROMLIST: psi: track changed states
  FROMLIST: psi: split update_stats into parts
  FROMLIST: psi: rename psi fields in preparation for psi trigger addition
  FROMLIST: psi: make psi_enable static
  FROMLIST: psi: introduce state_mask to represent stalled psi states
  ANDROID: cuttlefish_defconfig: Enable CONFIG_PSI
  UPSTREAM: kernel: cgroup: add poll file operation
  UPSTREAM: fs: kernfs: add poll file operation
  UPSTREAM: psi: avoid divide-by-zero crash inside virtual machines
  UPSTREAM: psi: clarify the Kconfig text for the default-disable option
  UPSTREAM: psi: fix aggregation idle shut-off
  UPSTREAM: psi: fix reference to kernel commandline enable
  UPSTREAM: psi: make disabling/enabling easier for vendor kernels
  UPSTREAM: kernel/sched/psi.c: simplify cgroup_move_task()
  UPSTREAM: psi: cgroup support
  UPSTREAM: psi: pressure stall information for CPU, memory, and IO
  UPSTREAM: sched: introduce this_rq_lock_irq()
  UPSTREAM: sched: sched.h: make rq locking and clock functions available in stats.h
  UPSTREAM: sched: loadavg: make calc_load_n() public
  BACKPORT: sched: loadavg: consolidate LOAD_INT, LOAD_FRAC, CALC_LOAD
  UPSTREAM: delayacct: track delays from thrashing cache pages
  UPSTREAM: mm: workingset: tell cache transitions from workingset thrashing

Conflicts:
	arch/arm/kernel/irq.c
	drivers/scsi/sd.c
	include/linux/sched.h
	init/Kconfig
	kernel/sched/Makefile
	kernel/sched/sched.h
	kernel/workqueue.c
	sound/soc/soc-dapm.c

Change-Id: Ia2dcc01c712134c57037ca6788d51172f66bcd93
Signed-off-by: Ivaylo Georgiev <irgeorgiev@codeaurora.org>
2019-04-05 01:06:22 -07:00
Samuel Holland
e19ca3fe6c clocksource/drivers/arch_timer: Workaround for Allwinner A64 timer instability
commit c950ca8c35eeb32224a63adc47e12f9e226da241 upstream.

The Allwinner A64 SoC is known[1] to have an unstable architectural
timer, which manifests itself most obviously in the time jumping forward
a multiple of 95 years[2][3]. This coincides with 2^56 cycles at a
timer frequency of 24 MHz, implying that the time went slightly backward
(and this was interpreted by the kernel as it jumping forward and
wrapping around past the epoch).

Investigation revealed instability in the low bits of CNTVCT at the
point a high bit rolls over. This leads to power-of-two cycle forward
and backward jumps. (Testing shows that forward jumps are about twice as
likely as backward jumps.) Since the counter value returns to normal
after an indeterminate read, each "jump" really consists of both a
forward and backward jump from the software perspective.

Unless the kernel is trapping CNTVCT reads, a userspace program is able
to read the register in a loop faster than it changes. A test program
running on all 4 CPU cores that reported jumps larger than 100 ms was
run for 13.6 hours and reported the following:

 Count | Event
-------+---------------------------
  9940 | jumped backward      699ms
   268 | jumped backward     1398ms
     1 | jumped backward     2097ms
 16020 | jumped forward       175ms
  6443 | jumped forward       699ms
  2976 | jumped forward      1398ms
     9 | jumped forward    356516ms
     9 | jumped forward    357215ms
     4 | jumped forward    714430ms
     1 | jumped forward   3578440ms

This works out to a jump larger than 100 ms about every 5.5 seconds on
each CPU core.

The largest jump (almost an hour!) was the following sequence of reads:
    0x0000007fffffffff → 0x00000093feffffff → 0x0000008000000000

Note that the middle bits don't necessarily all read as all zeroes or
all ones during the anomalous behavior; however the low 10 bits checked
by the function in this patch have never been observed with any other
value.

Also note that smaller jumps are much more common, with backward jumps
of 2048 (2^11) cycles observed over 400 times per second on each core.
(Of course, this is partially explained by lower bits rolling over more
frequently.) Any one of these could have caused the 95 year time skip.

Similar anomalies were observed while reading CNTPCT (after patching the
kernel to allow reads from userspace). However, the CNTPCT jumps are
much less frequent, and only small jumps were observed. The same program
as before (except now reading CNTPCT) observed after 72 hours:

 Count | Event
-------+---------------------------
    17 | jumped backward      699ms
    52 | jumped forward       175ms
  2831 | jumped forward       699ms
     5 | jumped forward      1398ms

Further investigation showed that the instability in CNTPCT/CNTVCT also
affected the respective timer's TVAL register. The following values were
observed immediately after writing CNVT_TVAL to 0x10000000:

 CNTVCT             | CNTV_TVAL  | CNTV_CVAL          | CNTV_TVAL Error
--------------------+------------+--------------------+-----------------
 0x000000d4a2d8bfff | 0x10003fff | 0x000000d4b2d8bfff | +0x00004000
 0x000000d4a2d94000 | 0x0fffffff | 0x000000d4b2d97fff | -0x00004000
 0x000000d4a2d97fff | 0x10003fff | 0x000000d4b2d97fff | +0x00004000
 0x000000d4a2d9c000 | 0x0fffffff | 0x000000d4b2d9ffff | -0x00004000

The pattern of errors in CNTV_TVAL seemed to depend on exactly which
value was written to it. For example, after writing 0x10101010:

 CNTVCT             | CNTV_TVAL  | CNTV_CVAL          | CNTV_TVAL Error
--------------------+------------+--------------------+-----------------
 0x000001ac3effffff | 0x1110100f | 0x000001ac4f10100f | +0x1000000
 0x000001ac40000000 | 0x1010100f | 0x000001ac5110100f | -0x1000000
 0x000001ac58ffffff | 0x1110100f | 0x000001ac6910100f | +0x1000000
 0x000001ac66000000 | 0x1010100f | 0x000001ac7710100f | -0x1000000
 0x000001ac6affffff | 0x1110100f | 0x000001ac7b10100f | +0x1000000
 0x000001ac6e000000 | 0x1010100f | 0x000001ac7f10100f | -0x1000000

I was also twice able to reproduce the issue covered by Allwinner's
workaround[4], that writing to TVAL sometimes fails, and both CVAL and
TVAL are left with entirely bogus values. One was the following values:

 CNTVCT             | CNTV_TVAL  | CNTV_CVAL
--------------------+------------+--------------------------------------
 0x000000d4a2d6014c | 0x8fbd5721 | 0x000000d132935fff (615s in the past)
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>

========================================================================

Because the CPU can read the CNTPCT/CNTVCT registers faster than they
change, performing two reads of the register and comparing the high bits
(like other workarounds) is not a workable solution. And because the
timer can jump both forward and backward, no pair of reads can
distinguish a good value from a bad one. The only way to guarantee a
good value from consecutive reads would be to read _three_ times, and
take the middle value only if the three values are 1) each unique and
2) increasing. This takes at minimum 3 counter cycles (125 ns), or more
if an anomaly is detected.

However, since there is a distinct pattern to the bad values, we can
optimize the common case (1022/1024 of the time) to a single read by
simply ignoring values that match the error pattern. This still takes no
more than 3 cycles in the worst case, and requires much less code. As an
additional safety check, we still limit the loop iteration to the number
of max-frequency (1.2 GHz) CPU cycles in three 24 MHz counter periods.

For the TVAL registers, the simple solution is to not use them. Instead,
read or write the CVAL and calculate the TVAL value in software.

Although the manufacturer is aware of at least part of the erratum[4],
there is no official name for it. For now, use the kernel-internal name
"UNKNOWN1".

[1]: https://github.com/armbian/build/commit/a08cd6fe7ae9
[2]: https://forum.armbian.com/topic/3458-a64-datetime-clock-issue/
[3]: https://irclog.whitequark.org/linux-sunxi/2018-01-26
[4]: https://github.com/Allwinner-Homlet/H6-BSP4.9-linux/blob/master/drivers/clocksource/arm_arch_timer.c#L272

Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 20:09:58 +01:00
Channagoud Kadabi
ee514e9083 drivers: clksource: Add API to return cval
Sleep driver needs to program the absolute clock value for next expiry
into pdc register for system wake up. Add an API to read the cval low
and high counters.

Change-Id: I3f08b3320ea281894d46f3c4bb0862784cc337a1
Signed-off-by: Channagoud Kadabi <ckadabi@codeaurora.org>
2018-10-29 11:12:09 -06:00
Prasad Sodagudi
95c2507cae clocksource: arch_timer: Use _no_log variants while accessing registers
arch_timer register accesses happen more frequently flooding the
RTB logs. Since they are not that useful for debugging purposes,
use _no_log variants while accessing those registers.

Change-Id: Ide35ef1a01e4792c1b3b7b7be7ad3f069dc2f694
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
Signed-off-by: Rishabh Bhatnagar <rishabhb@codeaurora.org>
2018-08-03 10:20:06 -07:00
Se Wang (Patrick) Oh
0ad7134724 ARM: arch_timer: force re-selection of the best clocksource
As the best clocksource is not selected till core boot completion,
only periodic tick timer works and it increases jiffies by one at
every tick updates. If interrupt is disabled more than one tick(10ms),
timer interrupts are missed and jiffies can't be updated at every
10ms and It can be behind the real time. So make it possible to select
the best clocksource right after arm arch timer initialization, so that
jiffies can be increased by multiple counts since then.

Change-Id: Id8c4e3ce9b9e44061fef7ad7e678ca1c27d84bb1
Signed-off-by: Se Wang (Patrick) Oh <sewango@codeaurora.org>
Signed-off-by: Venkata Narendra Kumar Gutta <vnkgutta@codeaurora.org>
2018-07-31 14:47:53 -07:00
Sudeep Holla
5e18e41297 clocksource: arm_arch_timer: Set arch_mem_timer cpumask to cpu_possible_mask
Currently, arch_mem_timer cpumask is set to cpu_all_mask which should be
fine. However, cpu_possible_mask is more accurate and if there are other
clockevent source in the system which are set to cpu_possible_mask, then
having cpu_all_mask may result in issue.

E.g. on a platform with arm,sp804 timer with rating 300 and
cpu_possible_mask and this arch_mem_timer timer with rating 400 and
cpu_all_mask, tick_check_preferred may choose both preferred as the
cpumasks are not equal though they must be.

This issue was root caused incorrectly initially and a fix was merged as
commit 1332a90558 ("tick: Prefer a lower rating device only if it's CPU
local device").

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/1531151136-18297-2-git-send-email-sudeep.holla@arm.com
2018-07-10 22:12:47 +02:00
Linus Torvalds
974aa5630b Merge tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Radim Krčmář:
 "First batch of KVM changes for 4.15

  Common:
   - Python 3 support in kvm_stat
   - Accounting of slabs to kmemcg

  ARM:
   - Optimized arch timer handling for KVM/ARM
   - Improvements to the VGIC ITS code and introduction of an ITS reset
     ioctl
   - Unification of the 32-bit fault injection logic
   - More exact external abort matching logic

  PPC:
   - Support for running hashed page table (HPT) MMU mode on a host that
     is using the radix MMU mode; single threaded mode on POWER 9 is
     added as a pre-requisite
   - Resolution of merge conflicts with the last second 4.14 HPT fixes
   - Fixes and cleanups

  s390:
   - Some initial preparation patches for exitless interrupts and crypto
   - New capability for AIS migration
   - Fixes

  x86:
   - Improved emulation of LAPIC timer mode changes, MCi_STATUS MSRs,
     and after-reset state
   - Refined dependencies for VMX features
   - Fixes for nested SMI injection
   - A lot of cleanups"

* tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (89 commits)
  KVM: s390: provide a capability for AIS state migration
  KVM: s390: clear_io_irq() requests are not expected for adapter interrupts
  KVM: s390: abstract conversion between isc and enum irq_types
  KVM: s390: vsie: use common code functions for pinning
  KVM: s390: SIE considerations for AP Queue virtualization
  KVM: s390: document memory ordering for kvm_s390_vcpu_wakeup
  KVM: PPC: Book3S HV: Cosmetic post-merge cleanups
  KVM: arm/arm64: fix the incompatible matching for external abort
  KVM: arm/arm64: Unify 32bit fault injection
  KVM: arm/arm64: vgic-its: Implement KVM_DEV_ARM_ITS_CTRL_RESET
  KVM: arm/arm64: Document KVM_DEV_ARM_ITS_CTRL_RESET
  KVM: arm/arm64: vgic-its: Free caches when GITS_BASER Valid bit is cleared
  KVM: arm/arm64: vgic-its: New helper functions to free the caches
  KVM: arm/arm64: vgic-its: Remove kvm_its_unmap_device
  arm/arm64: KVM: Load the timer state when enabling the timer
  KVM: arm/arm64: Rework kvm_timer_should_fire
  KVM: arm/arm64: Get rid of kvm_timer_flush_hwstate
  KVM: arm/arm64: Avoid phys timer emulation in vcpu entry/exit
  KVM: arm/arm64: Move phys_timer_emulate function
  KVM: arm/arm64: Use kvm_arm_timer_set/get_reg for guest register traps
  ...
2017-11-16 13:00:24 -08:00
Linus Torvalds
c9b012e5f4 Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
 "The big highlight is support for the Scalable Vector Extension (SVE)
  which required extensive ABI work to ensure we don't break existing
  applications by blowing away their signal stack with the rather large
  new vector context (<= 2 kbit per vector register). There's further
  work to be done optimising things like exception return, but the ABI
  is solid now.

  Much of the line count comes from some new PMU drivers we have, but
  they're pretty self-contained and I suspect we'll have more of them in
  future.

  Plenty of acronym soup here:

   - initial support for the Scalable Vector Extension (SVE)

   - improved handling for SError interrupts (required to handle RAS
     events)

   - enable GCC support for 128-bit integer types

   - remove kernel text addresses from backtraces and register dumps

   - use of WFE to implement long delay()s

   - ACPI IORT updates from Lorenzo Pieralisi

   - perf PMU driver for the Statistical Profiling Extension (SPE)

   - perf PMU driver for Hisilicon's system PMUs

   - misc cleanups and non-critical fixes"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (97 commits)
  arm64: Make ARMV8_DEPRECATED depend on SYSCTL
  arm64: Implement __lshrti3 library function
  arm64: support __int128 on gcc 5+
  arm64/sve: Add documentation
  arm64/sve: Detect SVE and activate runtime support
  arm64/sve: KVM: Hide SVE from CPU features exposed to guests
  arm64/sve: KVM: Treat guest SVE use as undefined instruction execution
  arm64/sve: KVM: Prevent guests from using SVE
  arm64/sve: Add sysctl to set the default vector length for new processes
  arm64/sve: Add prctl controls for userspace vector length management
  arm64/sve: ptrace and ELF coredump support
  arm64/sve: Preserve SVE registers around EFI runtime service calls
  arm64/sve: Preserve SVE registers around kernel-mode NEON use
  arm64/sve: Probe SVE capabilities and usable vector lengths
  arm64: cpufeature: Move sys_caps_initialised declarations
  arm64/sve: Backend logic for setting the vector length
  arm64/sve: Signal handling support
  arm64/sve: Support vector length resetting for new processes
  arm64/sve: Core task context handling
  arm64/sve: Low-level CPU setup
  ...
2017-11-15 10:56:56 -08:00
Christoffer Dall
e6d68b00e9 arm64: Use physical counter for in-kernel reads when booted in EL2
Using the physical counter allows KVM to retain the offset between the
virtual and physical counter as long as it is actively running a VCPU.

As soon as a VCPU is released, another thread is scheduled or we start
running userspace applications, we reset the offset to 0, so that
userspace accessing the virtual timer can still read the virtual counter
and get the same view of time as the kernel.

This opens up potential improvements for KVM performance, but we have to
make a few adjustments to preserve system consistency.

Currently get_cycles() is hardwired to arch_counter_get_cntvct() on
arm64, but as we move to using the physical timer for the in-kernel
time-keeping on systems that boot in EL2, we should use the same counter
for get_cycles() as for other in-kernel timekeeping operations.

Similarly, implementations of arch_timer_set_next_event_phys() is
modified to use the counter specific to the timer being programmed.

VHE kernels or kernels continuing to use the virtual timer are
unaffected.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-11-06 16:23:09 +01:00
Christoffer Dall
f2e600c149 arm64: Implement arch_counter_get_cntpct to read the physical counter
As we are about to use the physical counter on arm64 systems that have
KVM support, implement arch_counter_get_cntpct() and the associated
errata workaround functionality for stable timer reads.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-06 16:23:08 +01:00
Mark Rutland
a7fb4577bb clocksource/drivers/arm_arch_timer: Fix DEFINE_PER_CPU expansion
Our ctags mangling script can't handle newlines inside of a
DEFINE_PER_CPU(), leading to an annoying message whenever tags are
built:

  ctags: Warning: drivers/clocksource/arm_arch_timer.c:302: null expansion of name pattern "\1"

This was dealt with elsewhere in commit:

  25528213fe ("tags: Fix DEFINE_PER_CPU expansions")

... by ensuring each DEFINE_PER_CPU() was contained on a single line,
even where this would violate the usual code style (checkpatch warnings
and all).

Let's do the same for the arch timer driver, and get rid of the
distraction.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-10-19 23:49:06 +02:00
Ard Biesheuvel
21492e1333 clocksource/drivers/arm_arch_timer: Validate CNTFRQ after enabling frame
The ACPI GTDT code validates the CNTFRQ field of each MMIO timer
frame against the CNTFRQ system register of the current CPU, to
ensure that they are equal, which is mandated by the architecture.

However, reading the CNTFRQ field of a frame is not possible until
the RFRQ bit in the frame's CNTACRn register is set, and doing so
before that willl produce the following error:

  arch_timer: [Firmware Bug]: CNTFRQ mismatch: frame @ 0x00000000e0be0000: (0x00000000), CPU: (0x0ee6b280)
  arch_timer: Disabling MMIO timers due to CNTFRQ mismatch
  arch_timer: Failed to initialize memory-mapped timer.

The reason is that the CNTFRQ field is RES0 if access is not enabled.

So move the validation of CNTFRQ into the loop that iterates over the
timers to find the best frame, but defer it until after we have selected
the best frame, which should also have enabled the RFRQ bit.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-10-19 23:49:05 +02:00
Julien Thierry
ec5c8e429d arm_arch_timer: Expose event stream status
The arch timer configuration for a CPU might get reset after suspending
said CPU.

In order to reliably use the event stream in the kernel (e.g. for delays),
we keep track of the state where we can safely consider the event stream as
properly configured. After writing to cntkctl, we issue an ISB to ensure
that subsequent delay loops can rely on the event stream being enabled.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-13 18:55:05 +01:00
Ingo Molnar
10c9850cb2 Merge branch 'linus' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-25 11:04:51 +02:00
Matthias Kaehlcke
d197f79887 clocksource/drivers/arm_arch_timer: Fix mem frame loop initialization
The loop to find the best memory frame in arch_timer_mem_acpi_init()
initializes the loop counter with itself ('i = i'), which is suspicious
in the first place and pointed out by clang. The loop condition is
'i < timer_count' and a prior for loop exits when 'i' reaches
'timer_count', therefore the second loop is never executed.

Initialize the loop counter with 0 to iterate over all timers, which
supposedly was the intention before the typo monster attacked.

Fixes: c2743a3676 ("clocksource: arm_arch_timer: add GTDT support for memory-mapped timer")
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-08-10 14:48:17 +02:00
Marc Zyngier
450f9689f2 clocksource/arm_arch_timer: Use static_branch_enable_cpuslocked()
Use the new static_branch_enable_cpuslocked() function to switch
the workaround static key on the CPU hotplug path.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20170801080257.5056-5-marc.zyngier@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10 12:29:00 +02:00
Thomas Gleixner
f0cd9ae5d0 Merge branch 'timers/urgent' into timers/core
Pick up dependent changes.
2017-06-21 09:07:52 +02:00
Daniel Lezcano
77d62f5322 clocksource/drivers: Rename CLOCKSOURCE_ACPI_DECLARE to TIMER_ACPI_DECLARE
The macro name is now renamed to 'TIMER_ACPI_DECLARE' for consistency
with the CLOCKSOURCE_OF_DECLARE => TIMER_OF_DECLARE change.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-14 11:59:53 +02:00
Daniel Lezcano
1727339590 clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE
The CLOCKSOURCE_OF_DECLARE macro is used widely for the timers to declare the
clocksource at early stage. However, this macro is also used to initialize
the clockevent if any, or the clockevent only.

It was originally suggested to declare another macro to initialize a
clockevent, so in order to separate the two entities even they belong to the
same IP. This was not accepted because of the impact on the DT where splitting
a clocksource/clockevent definition does not make sense as it is a Linux
concept not a hardware description.

On the other side, the clocksource has not interrupt declared while the
clockevent has, so it is easy from the driver to know if the description is
for a clockevent or a clocksource, IOW it could be implemented at the driver
level.

So instead of dealing with a named clocksource macro, let's use a more generic
one: TIMER_OF_DECLARE.

The patch has not functional changes.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-14 11:58:45 +02:00
Frank Rowand
3db1200ca2 clocksource/drivers/arm_arch_timer: Fix read and iounmap of incorrect variable
Fix boot warning 'Trying to vfree() nonexistent vm area'
from arch_timer_mem_of_init().

Refactored code attempts to read and iounmap using address frame
instead of address ioremap(frame->cntbase).

Fixes: c389d701df ("clocksource: arm_arch_timer: split MMIO timer probing.")

Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Reviewed-by: Fu Wei <fu.wei@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-12 15:00:23 +02:00
Sudeep Holla
f63d947c16 clocksource/arm_arch_timer: Fix arch_timer_mem_find_best_frame()
arch_timer_mem_find_best_frame() looks through ARCH_TIMER_MEM_MAX_FRAMES
frames even after finding matches to ensure the best frame is chosen,
which means the variable frame will point to the last valid frame but
not necessarily the best frame.

On Juno, we get the following error as the wrong frame is returned as the
best frame from arch_timer_mem_find_best_frame():

  arch_timer: Unable to map frame @ 0x0000000000000000
  arch_timer: Frame missing phys irq.
  Failed to initialize '/timer@2a810000': -22

Fix the issue by correctly returning the best frame from
arch_timer_mem_find_best_frame().

Fixes: c389d701df ("clocksource: arm_arch_timer: split MMIO timer probing.")
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1494246747-17267-1-git-send-email-sudeep.holla@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-05-09 08:56:41 +02:00
Arnd Bergmann
eb64522100 arm64/arch_timer: Mark errata handlers as __maybe_unused
In some rare randconfig builds, we end up with two functions being entirely
unused:

drivers/clocksource/arm_arch_timer.c:342:12: error: 'erratum_set_next_event_tval_phys' defined but not used [-Werror=unused-function]
 static int erratum_set_next_event_tval_phys(unsigned long evt,
drivers/clocksource/arm_arch_timer.c:335:12: error: 'erratum_set_next_event_tval_virt' defined but not used [-Werror=unused-function]
 static int erratum_set_next_event_tval_virt(unsigned long evt,

We could add an #ifdef around them, but we would already have to check for
several symbols there and there is a chance this would get more complicated
over time, so marking them as __maybe_unused is the simplest way to avoid the
harmless warnings.

Fixes: 01d3e3ff26 ("arm64: arch_timer: Rework the set_next_event workarounds")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Link: http://lkml.kernel.org/r/20170419173737.3846098-1-arnd@arndb.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-20 14:56:59 +02:00
Fu Wei
c2743a3676 clocksource: arm_arch_timer: add GTDT support for memory-mapped timer
The patch add memory-mapped timer register support by using the
information provided by the new GTDT driver of ACPI.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
[Mark: verify CNTFRQ, only register the first frame]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-19 17:00:15 +01:00
Fu Wei
f79d209405 clocksource: arm_arch_timer: simplify ACPI support code.
The patch update arm_arch_timer driver to use the function
provided by the new GTDT driver of ACPI.
By this way, arm_arch_timer.c can be simplified, and separate
all the ACPI GTDT knowledge from this timer driver.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-19 16:11:49 +01:00
Fu Wei
c389d701df clocksource: arm_arch_timer: split MMIO timer probing.
Currently the code to probe MMIO architected timers mixes DT parsing with
actual poking of hardware. This makes the code harder than necessary to
understand, and makes it difficult to add support for probing via ACPI.

This patch splits the DT parsing from HW probing. The DT parsing now
lives in arch_timer_mem_of_init(), which fills in an arch_timer_mem
structure that it hands to probing functions that can be reused for ACPI
support.

Since the rate detection logic will be slight different when using ACPI,
the probing is performed as a number of steps. This results in more code
for the moment, and some arguably redundant work, but simplifies matters
considerably when ACPI support is added.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
[Mark: refactor the probing split]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-19 16:11:48 +01:00
Fu Wei
ca0e1b5214 clocksource: arm_arch_timer: move arch_timer_needs_of_probing into DT init call
To cleanly split code paths specific to ACPI or DT at a higher level,
this patch removes arch_timer_init(), folding the relevant
parts of its logic into existing callers.

This pathes the way for further rework, and saves a few lines.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-19 16:11:47 +01:00
Fu Wei
13bf6992fe clocksource: arm_arch_timer: refactor arch_timer_needs_probing
When booting with DT, it's possible for timer nodes to be probed in any
order. Some common initialisation needs to occur after all nodes have
been probed, and arch_timer_common_init() has code to detect when this
has happened.

This logic is DT-specific, and it would be best to factor it out of the
common code that will be shared with ACPI.

This patch folds this into the existing arch_timer_needs_probing(),
which is renamed to arch_timer_needs_of_probing(), and no longer takes
any arguments. This is only called when using DT, and not when using
ACPI, which will have a deterministic probe order.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-19 16:11:47 +01:00
Fu Wei
5d3dfa96c7 clocksource: arm_arch_timer: split dt-only rate handling
For historical reasons, rate detection when probing via DT is somewhat
convoluted. We tried to package this up in arch_timer_detect_rate(), but
with the addition of ACPI worse, and gets in the way of stringent rate
checking when ACPI is used.

This patch makes arch_timer_detect_rate() specific to DT, ripping out
ACPI logic. In preparation for rework of the MMIO timer probing, the
reading of the relevant CNTFRQ register is factored out to callers. The
function is then renamed to arch_timer_of_configure_rate(), which better
represents its new place in the world.

Comments are added in the DT and ACPI probe paths to explain this.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-19 16:11:37 +01:00
Fu Wei
4502b6bb72 clocksource: arm_arch_timer: rework PPI selection
Currently, the arch timer driver uses ARCH_TIMER_PHYS_SECURE_PPI to mean
the driver will use the secure PPI *and* potentially also use the
non-secure PPI. This is somewhat confusing.

For arm64 it never makes sense to use the secure PPI, but we do anyway,
inheriting this behaviour from 32-bit arm. For ACPI, we may not even
have a valid secure PPI, so we need to be able to only request the
non-secure PPI.

To that end, this patch reworks the timer driver so that we can request
the non-secure PPI alone. The PPI selection is split out into a new
function, arch_timer_select_ppi(), and verification of the selected PPI
is shifted out to callers (as DT may select the PPI by other means and
must handle this anyway).

We now consistently use arch_timer_has_nonsecure_ppi() to determine
whether we must manage a non-secure PPI *in addition* to a secure PPI.
When we only have a non-secure PPI, this returns false.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10 14:29:54 +01:00
Fu Wei
097cd143dd clocksource: arm_arch_timer: add a new enum for spi type
This patch add a new enum "arch_timer_spi_nr" and use it in the driver.
Just for code's readability, no functional change.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10 14:29:54 +01:00
Fu Wei
831610c08e clocksource: arm_arch_timer: move enums and defines to header file
To support the arm_arch_timer via ACPI we need to share defines and enums
between the driver and the ACPI parser code.
So we split out the relevant defines and enums into arm_arch_timer.h.

No functional change.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10 14:29:54 +01:00
Fu Wei
ee34f1e63d clocksource: arm_arch_timer: rename the PPI enum
In preparation for moving the PPI enum out into a header, rename the
enum and its constituent values these so they are namespaced w.r.t. the
arch timer. This will aid consistency and avoid potential name clashes
when this move occurs.

No functional change.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10 14:29:53 +01:00
Fu Wei
8a5c21dc05 clocksource: arm_arch_timer: rename type macros
In preparation for moving the type macros out into a header, rename
these so they are namespaced w.r.t. the arch timer. We'll apply the same
prefix to other definitions in subsequent patches. This will aid
consistency and avoid potential name clahses when this move occurs.

No functional change.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10 14:25:34 +01:00
Fu Wei
ded24019b6 clocksource: arm_arch_timer: clean up printk usage
Almost all string in the arm_arch_timer driver duplicate an common
prefix (though a few do not). For consistency, it would be better to use
pr_fmt(), and always use this prefix. At the same time, we may as well
clean up some whitespace issues in arch_timer_banner and
arch_timer_init.

No functional change.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10 14:25:34 +01:00
Marc Zyngier
d003d029ce arm64: arch_timer: Add HISILICON_ERRATUM_161010101 ACPI matching data
In order to deal with ACPI enabled platforms suffering from the
HISILICON_ERRATUM_161010101, let's add the required OEM data that
allow the workaround to be enabled.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: dann frazier <dann.frazier@canonical.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:10 +01:00
Marc Zyngier
5a38bcac1f arm64: arch_timer: Allow erratum matching with ACPI OEM information
Just as we're able to identify a broken platform using some DT
information, let's enable a way to spot the offenders with ACPI.

The difference is that we can only match on some OEM info instead
of implementation-specific properties. So in order to avoid the
insane multiplication of errata structures, we allow an array
of OEM descriptions to be attached to an erratum structure.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: dann frazier <dann.frazier@canonical.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:10 +01:00
Marc Zyngier
fa8d815fac arm64: arch_timer: Workaround for Cortex-A73 erratum 858921
Cortex-A73 (all versions) counter read can return a wrong value
when the counter crosses a 32bit boundary.

The workaround involves performing the read twice, and to return
one or the other depending on whether a transition has taken place.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:10 +01:00
Marc Zyngier
a86bd139f2 arm64: arch_timer: Enable CNTVCT_EL0 trap if workaround is enabled
Userspace being allowed to use read CNTVCT_EL0 anytime (and not
only in the VDSO), we need to enable trapping whenever a cntvct
workaround is enabled on a given CPU.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:09 +01:00
Marc Zyngier
bee67c53a9 arm64: arch_timer: Save cntkctl_el1 as a per-cpu variable
As we're about to allow per CPU cntkctl_el1 configuration, we cannot
rely on the register value to be common when performing power
management.

Let's turn saved_cntkctl into a per-cpu variable.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:09 +01:00
Marc Zyngier
992dd16f65 arm64: arch_timer: Move clocksource_counter and co around
In order to access clocksource_counter from the errata handling code,
move it (together with the related structures and functions) towards
the top of the file.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:09 +01:00
Marc Zyngier
6acc71ccac arm64: arch_timer: Allows a CPU-specific erratum to only affect a subset of CPUs
Instead of applying a CPU-specific workaround to all CPUs in the system,
allow it to only affect a subset of them (typical big-little case).

This is done by turning the erratum pointer into a per-CPU variable.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:09 +01:00
Marc Zyngier
01d3e3ff26 arm64: arch_timer: Rework the set_next_event workarounds
The way we work around errata affecting set_next_event is not very
nice, at it imposes this workaround on errata that do not need it.

Add new workaround hooks and let the existing workarounds use them.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:09 +01:00
Marc Zyngier
8328089f0a arm64: arch_timer: Get rid of erratum_workaround_set_sne
Let's move the handling of workarounds affecting set_next_event
to the affected function, instead of overriding the pointers
as an afterthough. Yes, this is an extra indirection on the
erratum handling path, but the HW is busted anyway.

This will allow for some more flexibility later.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:09 +01:00
Marc Zyngier
f4e00a1a55 arm64: arch_timer: Move arch_timer_reg_read/write around
As we're about to move things around, let's start with the low
level read/write functions. This allows us to use these functions
in the errata handling code without having to use forward declaration
of static functions.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:08 +01:00
Marc Zyngier
0064030c6f arm64: arch_timer: Add erratum handler for CPU-specific capability
Should we ever have a workaround for an erratum that is detected using
a capability and affecting a particular CPU, it'd be nice to have
a way to probe them directly.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:08 +01:00
Marc Zyngier
651bb2e9dc arm64: arch_timer: Add infrastructure for multiple erratum detection methods
We're currently stuck with DT when it comes to handling errata, which
is pretty restrictive. In order to make things more flexible, let's
introduce an infrastructure that could support alternative discovery
methods. No change in functionality.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07 11:22:08 +01:00