Commit Graph

313 Commits

Author SHA1 Message Date
Linus Torvalds d34687ab97 ARC updates for 4.6-rc1
- Big Endian io accessors fix [Lada]
 - Spellos fixes [Adam]
 - Fix for DW GMAC breakage [Alexey]
 - Making DMA API 64-bit ready
 - Shutting up -Wmaybe-uninitialized noise for ARC
 - Other minor fixes here and there, comments update
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJW738lAAoJEGnX8d3iisJeProP/icm32aIHY0QXmJCBXCmQfLa
 HHzfBeJ2KsG8pIRgrvraK3FJkmFr+WxZ7x6b5hPNYeHIT3c179/GZ3DlssM1md0u
 sa50o5jmwd/J4o5jCKpUB/hx7wiAjpC2CYb6qIg39A2Nq5JhOFJV30XMbCscXkLI
 ae/o8oATi1502cf1OQ2EqNWKfME4ogG1KsEUNrSzcd+1P8LZxsnEVBmXuPHVdHLw
 kTHVgmCELsEchaV/QY9pY+uHkm9Y4vV18v0vqbklwED+cHkjmXQ2UysP3/J8KXKN
 PVSqmtUJIS2vxDGK5mWvz6jkWmU8gRXoT14ZqdmMARmhVhp3+JTm2fQ53NUwZ+b2
 JpPNGWVQRi86AaiUE8Fm+eWjC242CAm+lsBfx+mvqWpEvFGMlnRKw8oZiyeJhhIw
 3M1yrulQG7QbTSuQrgQwfGqtrhl2nnq+X0uoMJXYHupNDQ42QK8wmJ9bT7cmutD0
 K3Tmi84qoiSnN/HhWK/D9d60bLGvUY4RKiLjAcJz7lbMjtRhT/rpFFcFYCIhJyZs
 y//jOZK67o1ecDXBTaUcvT+edOrQVsmatn3w0p9VwATe8OiKHsLA/0UD34gwiECy
 o9g/i4tc2GfOLFoLv66czXTU9IuoKDh3HrTJgET7r1Re/+FKgJ+2+GX6AbiJzbhY
 9jsAAI/ZpsS6qMhvSz3d
 =n0fk
 -----END PGP SIGNATURE-----

Merge tag 'arc-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

Pull ARC architecture updates from Vineet Gupta:
 - Big Endian io accessors fix [Lada]
 - Spellos fixes [Adam]
 - Fix for DW GMAC breakage [Alexey]
 - Making DMA API 64-bit ready
 - Shutting up -Wmaybe-uninitialized noise for ARC
 - Other minor fixes here and there, comments update

* tag 'arc-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (21 commits)
  ARCv2: ioremap: Support dynamic peripheral address space
  ARC: dma: reintroduce platform specific dma<->phys
  ARC: dma: ioremap: use phys_addr_t consistenctly in code paths
  ARC: dma: pass_phys() not sg_virt() to cache ops
  ARC: dma: non-coherent pages need V-P mapping if in HIGHMEM
  ARC: dma: Use struct page based page allocator helpers
  ARC: build: Turn off -Wmaybe-uninitialized for ARC gcc 4.8
  ARC: [plat-axs10x] add Ethernet PHY description in .dts
  arc: use of_platform_default_populate() to populate default bus
  ARC: thp: unbork !CONFIG_TRANSPARENT_HUGEPAGE build
  arc: [plat-nsimosci*] use ezchip network driver
  ARCv2: LLSC: software backoff is NOT needed starting HS2.1c
  ARC: mm: Use virt_to_pfn() for addr >> PAGE_SHIFT pattern
  ARC: [plat-nsim] document ranges
  ARC: build: Better way to detect ISA compatible toolchain
  ARCv2: Allow enabling PAE40 w/o HIGHMEM
  ARC: [BE] readl()/writel() to work in Big Endian CPU configuration
  ARC: [*defconfig] No need to specify CONFIG_CROSS_COMPILE
  ARC: [BE] Select correct CROSS_COMPILE prefix
  ARC: bitops: Remove non relevant comments
  ...
2016-03-21 13:00:46 -07:00
Vineet Gupta deaf7565eb ARCv2: ioremap: Support dynamic peripheral address space
The peripheral address space is architectural address window which is
uncached and typically used to wire up peripherals.

For ARC700 cores (ARCompact ISA based) this was fixed to 1GB region
0xC000_0000 - 0xFFFF_FFFF.

For ARCv2 based HS38 cores the start address is flexible and can be
0xC, 0xD, 0xE, 0xF 000_000 by programming AUX_NON_VOLATILE_LIMIT reg
(typically done in bootloader)

Further in cas of PAE, the physical address can extend beyond 4GB so
need to confine this check, otherwise all pages beyond 4GB will be
treated as uncached

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-19 14:34:10 +05:30
Kefeng Wang 26cf9cc5d8 arc: use of_platform_default_populate() to populate default bus
Use helper of_platform_default_populate() in linux/of_platform
when possible, instead of calling of_platform_populate() with
the default match table.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-17 17:45:15 +05:30
Linus Torvalds 63e30271b0 PCI changes for the v4.6 merge window:
Enumeration
     Disable IO/MEM decoding for devices with non-compliant BARs (Bjorn Helgaas)
     Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs (Bjorn Helgaas
 
   Resource management
     Mark shadow copy of VGA ROM as IORESOURCE_PCI_FIXED (Bjorn Helgaas)
     Don't assign or reassign immutable resources (Bjorn Helgaas)
     Don't enable/disable ROM BAR if we're using a RAM shadow copy (Bjorn Helgaas)
     Set ROM shadow location in arch code, not in PCI core (Bjorn Helgaas)
     Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs (Bjorn Helgaas)
     ia64: Use ioremap() instead of open-coded equivalent (Bjorn Helgaas)
     ia64: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
     MIPS: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
     Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY (Bjorn Helgaas)
     Don't leak memory if sysfs_create_bin_file() fails (Bjorn Helgaas)
     rcar: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
     designware: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
 
   Virtualization
     Wait for up to 1000ms after FLR reset (Alex Williamson)
     Support SR-IOV on any function type (Kelly Zytaruk)
     Add ACS quirk for all Cavium devices (Manish Jaggi)
 
   AER
     Rename pci_ops_aer to aer_inj_pci_ops (Bjorn Helgaas)
     Restore pci_ops pointer while calling original pci_ops (David Daney)
     Fix aer_inject error codes (Jean Delvare)
     Use dev_warn() in aer_inject (Jean Delvare)
     Log actual error causes in aer_inject (Jean Delvare)
     Log aer_inject error injections (Jean Delvare)
 
   VPD
     Prevent VPD access for buggy devices (Babu Moger)
     Move pci_read_vpd() and pci_write_vpd() close to other VPD code (Bjorn Helgaas)
     Move pci_vpd_release() from header file to pci/access.c (Bjorn Helgaas)
     Remove struct pci_vpd_ops.release function pointer (Bjorn Helgaas)
     Rename VPD symbols to remove unnecessary "pci22" (Bjorn Helgaas)
     Fold struct pci_vpd_pci22 into struct pci_vpd (Bjorn Helgaas)
     Sleep rather than busy-wait for VPD access completion (Bjorn Helgaas)
     Update VPD definitions (Hannes Reinecke)
     Allow access to VPD attributes with size 0 (Hannes Reinecke)
     Determine actual VPD size on first access (Hannes Reinecke)
 
   Generic host bridge driver
     Move structure definitions to separate header file (David Daney)
     Add pci_host_common_probe(), based on gen_pci_probe() (David Daney)
     Expose pci_host_common_probe() for use by other drivers (David Daney)
 
   Altera host bridge driver
     Fix altera_pcie_link_is_up() (Ley Foon Tan)
 
   Cavium ThunderX host bridge driver
     Add PCIe host driver for ThunderX processors (David Daney)
     Add driver for ThunderX-pass{1,2} on-chip devices (David Daney)
 
   Freescale i.MX6 host bridge driver
     Add DT bindings to configure PHY Tx driver settings (Justin Waters)
     Move imx6_pcie_reset_phy() near other PHY handling functions (Lucas Stach)
     Move PHY reset into imx6_pcie_establish_link() (Lucas Stach)
     Remove broken Gen2 workaround (Lucas Stach)
     Move link up check into imx6_pcie_wait_for_link() (Lucas Stach)
 
   Freescale Layerscape host bridge driver
     Add "fsl,ls2085a-pcie" compatible ID (Yang Shi)
 
   Intel VMD host bridge driver
     Attach VMD resources to parent domain's resource tree (Jon Derrick)
     Set bus resource start to 0 (Keith Busch)
 
   Microsoft Hyper-V host bridge driver
     Add fwnode_handle to x86 pci_sysdata (Jake Oshins)
     Look up IRQ domain by fwnode_handle (Jake Oshins)
     Add paravirtual PCI front-end for Microsoft Hyper-V VMs (Jake Oshins)
 
   NVIDIA Tegra host bridge driver
     Add pci_ops.{add,remove}_bus() callbacks (Thierry Reding)
     Implement ->{add,remove}_bus() callbacks (Thierry Reding)
     Remove unused struct tegra_pcie.num_ports field (Thierry Reding)
     Track bus -> CPU mapping (Thierry Reding)
     Remove misleading PHYS_OFFSET (Thierry Reding)
 
   Renesas R-Car host bridge driver
     Depend on ARCH_RENESAS, not ARCH_SHMOBILE (Simon Horman)
 
   Synopsys DesignWare host bridge driver
     ARC: Add PCI support (Joao Pinto)
     Add generic dw_pcie_wait_for_link() (Joao Pinto)
     Add default link up check if sub-driver doesn't override (Joao Pinto)
     Add driver for prototyping kits based on ARC SDP (Joao Pinto)
 
   TI Keystone host bridge driver
     Defer probing if devm_phy_get() returns -EPROBE_DEFER (Shawn Lin)
 
   Xilinx AXI host bridge driver
     Use of_pci_get_host_bridge_resources() to parse DT (Bharat Kumar Gogada)
     Remove dependency on ARM-specific struct hw_pci (Bharat Kumar Gogada)
     Don't call pci_fixup_irqs() on Microblaze (Bharat Kumar Gogada)
     Update Zynq binding with Microblaze node (Bharat Kumar Gogada)
     microblaze: Support generic Xilinx AXI PCIe Host Bridge IP driver (Bharat Kumar Gogada)
 
   Xilinx NWL host bridge driver
     Add support for Xilinx NWL PCIe Host Controller (Bharat Kumar Gogada)
 
   Miscellaneous
     Check device_attach() return value always (Bjorn Helgaas)
     Move pci_set_flags() from asm-generic/pci-bridge.h to linux/pci.h (Bjorn Helgaas)
     Remove includes of empty asm-generic/pci-bridge.h (Bjorn Helgaas)
     ARM64: Remove generated include of asm-generic/pci-bridge.h (Bjorn Helgaas)
     Remove empty asm-generic/pci-bridge.h (Bjorn Helgaas)
     Remove includes of asm/pci-bridge.h (Bjorn Helgaas)
     Consolidate PCI DMA constants and interfaces in linux/pci-dma-compat.h (Bjorn Helgaas)
     unicore32: Remove unused HAVE_ARCH_PCI_SET_DMA_MASK definition (Bjorn Helgaas)
     Cleanup pci/pcie/Kconfig whitespace (Andreas Ziegler)
     Include pci/hotplug Kconfig directly from pci/Kconfig (Bjorn Helgaas)
     Include pci/pcie/Kconfig directly from pci/Kconfig (Bogicevic Sasa)
     frv: Remove stray pci_{alloc,free}_consistent() declaration (Christoph Hellwig)
     Move pci_dma_* helpers to common code (Christoph Hellwig)
     Add PCI_CLASS_SERIAL_USB_DEVICE definition (Heikki Krogerus)
     Add QEMU top-level IDs for (sub)vendor & device (Robin H. Johnson)
     Fix broken URL for Dell biosdevname (Naga Venkata Sai Indubhaskar Jupudi)
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJW6XgMAAoJEFmIoMA60/r8Yq4P/1nNwwZPikU+9Z8k0HyGPll6
 vqXBOYj/wlbAxJTzH2weaoyUamFrwvsKaO3Vap3xHkAeTFPD/Dp0TipCCNMrZ82Z
 j1y83JJpenkRyX6ifLARCNYpOtvnvgzSrO9x7Sb2Xfqb64dPb7+jGAfOpGNzhKsO
 n1nj/L7RGx8Q6fNFGf8ANMXKTsdkdL+1pdwegjUXmD5WdOT+oW8DmqVbhyfSKwl0
 E8r4Ml2lIg7Qd5Wu5iKMIBsR0+5HEyrwV7ch92wXChwKfoRwG70qnn7FGdc0y5ZB
 XvJuj8UD5UeMxEUeoRa9SwU6wWQT3Q9e6BzMS+P+43z36SPYjMfy/Xffv054z/bY
 rQomLjuGxNLESpmfNK5JfKxWoe2YNXjHQIDWMrAHyNlwdKJbYiwPcxnZJhvOa/eB
 p0QYcGS7O43STjibG9PZhzeq8tuSJRshxi0W6iB9QlqO8qs8nJQxIO+sZj/vl4yz
 lSnswWcV9062KITl8Fe9xDw244/RTz1xSVCdldlSoDhJyeMOjRvzS8raUMyyVmbA
 YULsI3l2iCl+fwDm/T21o7hJG966oYdAmgEv7lc7BWfgEAMg//LZXvMzVvrPFB2D
 R77u/0idtOciVJrmnO/x9DnQO2hzro9SLmVH6m0+0YU4wSSpZfGn98PCrtkatOAU
 c8zT9dJgyJVE3Z7cnPJ4
 =otsF
 -----END PGP SIGNATURE-----

Merge tag 'pci-v4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "PCI changes for v4.6:

  Enumeration:
   - Disable IO/MEM decoding for devices with non-compliant BARs (Bjorn Helgaas)
   - Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs (Bjorn Helgaas

  Resource management:
   - Mark shadow copy of VGA ROM as IORESOURCE_PCI_FIXED (Bjorn Helgaas)
   - Don't assign or reassign immutable resources (Bjorn Helgaas)
   - Don't enable/disable ROM BAR if we're using a RAM shadow copy (Bjorn Helgaas)
   - Set ROM shadow location in arch code, not in PCI core (Bjorn Helgaas)
   - Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs (Bjorn Helgaas)
   - ia64: Use ioremap() instead of open-coded equivalent (Bjorn Helgaas)
   - ia64: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
   - MIPS: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
   - Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY (Bjorn Helgaas)
   - Don't leak memory if sysfs_create_bin_file() fails (Bjorn Helgaas)
   - rcar: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
   - designware: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)

  Virtualization:
   - Wait for up to 1000ms after FLR reset (Alex Williamson)
   - Support SR-IOV on any function type (Kelly Zytaruk)
   - Add ACS quirk for all Cavium devices (Manish Jaggi)

  AER:
   - Rename pci_ops_aer to aer_inj_pci_ops (Bjorn Helgaas)
   - Restore pci_ops pointer while calling original pci_ops (David Daney)
   - Fix aer_inject error codes (Jean Delvare)
   - Use dev_warn() in aer_inject (Jean Delvare)
   - Log actual error causes in aer_inject (Jean Delvare)
   - Log aer_inject error injections (Jean Delvare)

  VPD:
   - Prevent VPD access for buggy devices (Babu Moger)
   - Move pci_read_vpd() and pci_write_vpd() close to other VPD code (Bjorn Helgaas)
   - Move pci_vpd_release() from header file to pci/access.c (Bjorn Helgaas)
   - Remove struct pci_vpd_ops.release function pointer (Bjorn Helgaas)
   - Rename VPD symbols to remove unnecessary "pci22" (Bjorn Helgaas)
   - Fold struct pci_vpd_pci22 into struct pci_vpd (Bjorn Helgaas)
   - Sleep rather than busy-wait for VPD access completion (Bjorn Helgaas)
   - Update VPD definitions (Hannes Reinecke)
   - Allow access to VPD attributes with size 0 (Hannes Reinecke)
   - Determine actual VPD size on first access (Hannes Reinecke)

  Generic host bridge driver:
   - Move structure definitions to separate header file (David Daney)
   - Add pci_host_common_probe(), based on gen_pci_probe() (David Daney)
   - Expose pci_host_common_probe() for use by other drivers (David Daney)

  Altera host bridge driver:
   - Fix altera_pcie_link_is_up() (Ley Foon Tan)

  Cavium ThunderX host bridge driver:
   - Add PCIe host driver for ThunderX processors (David Daney)
   - Add driver for ThunderX-pass{1,2} on-chip devices (David Daney)

  Freescale i.MX6 host bridge driver:
   - Add DT bindings to configure PHY Tx driver settings (Justin Waters)
   - Move imx6_pcie_reset_phy() near other PHY handling functions (Lucas Stach)
   - Move PHY reset into imx6_pcie_establish_link() (Lucas Stach)
   - Remove broken Gen2 workaround (Lucas Stach)
   - Move link up check into imx6_pcie_wait_for_link() (Lucas Stach)

  Freescale Layerscape host bridge driver:
   - Add "fsl,ls2085a-pcie" compatible ID (Yang Shi)

  Intel VMD host bridge driver:
   - Attach VMD resources to parent domain's resource tree (Jon Derrick)
   - Set bus resource start to 0 (Keith Busch)

  Microsoft Hyper-V host bridge driver:
   - Add fwnode_handle to x86 pci_sysdata (Jake Oshins)
   - Look up IRQ domain by fwnode_handle (Jake Oshins)
   - Add paravirtual PCI front-end for Microsoft Hyper-V VMs (Jake Oshins)

  NVIDIA Tegra host bridge driver:
   - Add pci_ops.{add,remove}_bus() callbacks (Thierry Reding)
   - Implement ->{add,remove}_bus() callbacks (Thierry Reding)
   - Remove unused struct tegra_pcie.num_ports field (Thierry Reding)
   - Track bus -> CPU mapping (Thierry Reding)
   - Remove misleading PHYS_OFFSET (Thierry Reding)

  Renesas R-Car host bridge driver:
   - Depend on ARCH_RENESAS, not ARCH_SHMOBILE (Simon Horman)

  Synopsys DesignWare host bridge driver:
   - ARC: Add PCI support (Joao Pinto)
   - Add generic dw_pcie_wait_for_link() (Joao Pinto)
   - Add default link up check if sub-driver doesn't override (Joao Pinto)
   - Add driver for prototyping kits based on ARC SDP (Joao Pinto)

  TI Keystone host bridge driver:
   - Defer probing if devm_phy_get() returns -EPROBE_DEFER (Shawn Lin)

  Xilinx AXI host bridge driver:
   - Use of_pci_get_host_bridge_resources() to parse DT (Bharat Kumar Gogada)
   - Remove dependency on ARM-specific struct hw_pci (Bharat Kumar Gogada)
   - Don't call pci_fixup_irqs() on Microblaze (Bharat Kumar Gogada)
   - Update Zynq binding with Microblaze node (Bharat Kumar Gogada)
   - microblaze: Support generic Xilinx AXI PCIe Host Bridge IP driver (Bharat Kumar Gogada)

  Xilinx NWL host bridge driver:
   - Add support for Xilinx NWL PCIe Host Controller (Bharat Kumar Gogada)

  Miscellaneous:
   - Check device_attach() return value always (Bjorn Helgaas)
   - Move pci_set_flags() from asm-generic/pci-bridge.h to linux/pci.h (Bjorn Helgaas)
   - Remove includes of empty asm-generic/pci-bridge.h (Bjorn Helgaas)
   - ARM64: Remove generated include of asm-generic/pci-bridge.h (Bjorn Helgaas)
   - Remove empty asm-generic/pci-bridge.h (Bjorn Helgaas)
   - Remove includes of asm/pci-bridge.h (Bjorn Helgaas)
   - Consolidate PCI DMA constants and interfaces in linux/pci-dma-compat.h (Bjorn Helgaas)
   - unicore32: Remove unused HAVE_ARCH_PCI_SET_DMA_MASK definition (Bjorn Helgaas)
   - Cleanup pci/pcie/Kconfig whitespace (Andreas Ziegler)
   - Include pci/hotplug Kconfig directly from pci/Kconfig (Bjorn Helgaas)
   - Include pci/pcie/Kconfig directly from pci/Kconfig (Bogicevic Sasa)
   - frv: Remove stray pci_{alloc,free}_consistent() declaration (Christoph Hellwig)
   - Move pci_dma_* helpers to common code (Christoph Hellwig)
   - Add PCI_CLASS_SERIAL_USB_DEVICE definition (Heikki Krogerus)
   - Add QEMU top-level IDs for (sub)vendor & device (Robin H. Johnson)
   - Fix broken URL for Dell biosdevname (Naga Venkata Sai Indubhaskar Jupudi)"

* tag 'pci-v4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (94 commits)
  PCI: Add PCI_CLASS_SERIAL_USB_DEVICE definition
  PCI: designware: Add driver for prototyping kits based on ARC SDP
  PCI: designware: Add default link up check if sub-driver doesn't override
  PCI: designware: Add generic dw_pcie_wait_for_link()
  PCI: Cleanup pci/pcie/Kconfig whitespace
  PCI: Simplify pci_create_attr() control flow
  PCI: Don't leak memory if sysfs_create_bin_file() fails
  PCI: Simplify sysfs ROM cleanup
  PCI: Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY
  MIPS: Loongson 3: Keep CPU physical (not virtual) addresses in shadow ROM resource
  MIPS: Loongson 3: Use temporary struct resource * to avoid repetition
  ia64/PCI: Keep CPU physical (not virtual) addresses in shadow ROM resource
  ia64/PCI: Use ioremap() instead of open-coded equivalent
  ia64/PCI: Use temporary struct resource * to avoid repetition
  PCI: Clean up pci_map_rom() whitespace
  PCI: Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs
  PCI: thunder: Add driver for ThunderX-pass{1,2} on-chip devices
  PCI: thunder: Add PCIe host driver for ThunderX processors
  PCI: generic: Expose pci_host_common_probe() for use by other drivers
  PCI: generic: Add pci_host_common_probe(), based on gen_pci_probe()
  ...
2016-03-16 14:45:55 -07:00
Vineet Gupta b31ac42697 ARCv2: LLSC: software backoff is NOT needed starting HS2.1c
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-15 16:04:44 +05:30
Adam Buchbinder 7423cc0cae ARC: Fix misspellings in comments.
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-11 14:59:53 +05:30
Joao Pinto c1678ffcde ARC: Add PCI support
Add PCI support to ARC and update drivers/pci Makefile enabling the ARC
arch to use the generic PCI setup functions.

[bhelgaas: fold in Joao's pci-dma-compat.h & pci-bridge.h build fix (I
should have caught this myself, sorry]
Signed-off-by: Joao Pinto <jpinto@synopsys.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-10 14:44:13 -06:00
Thomas Gleixner fc6d73d674 arch/hotplug: Call into idle with a proper state
Let the non boot cpus call into idle with the corresponding hotplug state, so
the hotplug core can handle the further bringup. That's a first step to
convert the boot side of the hotplugged cpus to do all the synchronization
with the other side through the state machine. For now it'll only start the
hotplug thread and kick the full bringup of the cpu.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Rik van Riel <riel@redhat.com>
Cc: Rafael Wysocki <rafael.j.wysocki@intel.com>
Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-01 20:36:57 +01:00
Valentin Rothberg 9ef2d8be55 arc: SMP: CONFIG_ARC_IPI_DBG cleanup
Previous Commit ("ARC: SMP: No need for CONFIG_ARC_IPI_DBG") removed
the Kconfig option ARC_IPI_DBG.  Remove the last reference on this
option.

Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 14:15:39 +05:30
Vineet Gupta d73b73f562 ARC: SMP: No need for CONFIG_ARC_IPI_DBG
This was more relevant during SMP bringup.

The warning for bogus msg better be visible always.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 11:07:32 +05:30
Vineet Gupta 3dea30ca5b ARCv2: Elide sending new cross core intr if receiver didn't ack prev
ARConnect/MCIP IPI sending has a retry-wait loop in case caller had
not seen a previous such interrupt. Turns out that it is not needed at
all. Linux cross core calling allows coalescing multiple IPIs to same
receiver - it is fine as long as there is one.

This logic is built into upper layer already, at a higher level of
abstraction. ipi_send_msg_one() sets the actual msg payload, but it only
calls MCIP IPI sending if msg holder was empty (using
atomic-set-new-and-get-old construct). Thus it is unlikely that the
retry-wait looping was ever getting exercised at all.

Cc: Chuck Jordan <cjordan@synopsys.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 11:07:31 +05:30
Vineet Gupta 9681787930 ARCv2: SMP: Push IPI_IRQ into IPI provider
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 11:07:31 +05:30
Vineet Gupta dbcbc7e7ce ARC: [intc-compact] Remove IPI setup from ARCompact port
There is no real ARC700 based SMP SoC so remove IPI definition.
EZChip's SMP ARC700 is going to use a different intc and IPI provider
anyways.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 11:07:31 +05:30
Vineet Gupta bb143f814e ARCv2: SMP: Emulate IPI to self using software triggered interrupt
ARConnect/MCIP Inter-Core-Interrupt module can't send interrupt to
local core. So use core intc capability to trigger software
interrupt to self, using an unsued IRQ #21.

This showed up as csd deadlock with LTP trace_sched on a dual core
system. This test acts as scheduler fuzzer, triggering all sorts of
schedulting activity. Trouble starts with IPI to self, which doesn't get
delivered (effectively lost due to H/w capability), but the msg intended
to be sent remain enqueued in per-cpu @ipi_data.

All subsequent IPIs to this core from other cores get elided due to the
IPI coalescing optimization in ipi_send_msg_one() where a pending msg
implies an IPI already sent and assumes other core is yet to ack it.
After the elided IPI, other core simply goes into csd_lock_wait()
but never comes out as this core never sees the interrupt.

Fixes STAR 9001008624

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>        [4.2]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 11:07:28 +05:30
Vineet Gupta a150b085b6 ARCv2: boot report CCMs (Closely Coupled Memories)
- ARCv2 uses a seperate BCR for {I,D}CCM base address:
  ARCompact encoded both base/size in same BCR

- Size encoding in common BCR is different for ARCompact/ARCv2

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-18 17:30:18 +05:30
Vineet Gupta 98341f7dc9 ARCv2: boot print Low Latency Memory
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-18 17:30:17 +05:30
Vineet Gupta 0eca6fdb31 ARC: Assume multiplier is always present
It is unlikely that designs running Linux will not have multiplier.
Further the current support is not complete as tool don't generate a
multilib w/o multiplier.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-18 17:30:03 +05:30
Linus Torvalds e835a65f7a ARC fixes for 4.5
- Corner case of returning to delay slot from interrupt
 - Changing default interrupt prioiry level
 - Kconfig'ize support for super pages
 - Other minor fixes
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJWvxdUAAoJEGnX8d3iisJeRkYP/2HZAt4J6c5MPk/NSy8rabVX
 2bB1m5jYXlBmJAIsmWm+WcDL72MdrB1Owtc5tEN+hIoQQa2QQpxolp32IslHg0o8
 C9CCzmF+iR8wz3caVk3javpsbze23XbHho/kdx/l2Ed3Fi+syI/9jF1GiboydRtR
 X22an1lslA6Y44pYxFmSFcMCv7XclFkJNe1ltxsgN9/QapnNrE/HWqUIy+SMr2Oo
 Tpo3m/Dc+IfMMejYyupc3keyAhyeux69lJXPuOzYiurgGUIyXz15Un2mQ9gZWf0u
 W56L/55VpQVuah46qrp5CBTLmdJA5cBqr0F8RqmZAqrEYLgn5SD4IhDjamo1qsP/
 FfFh0cG955SoEyCsUOPILWUFR5TeS4rJK+ZJjErUb+dwEC1BWZR0/Dn1s9KJN8b7
 GgGV8yXruDACFlFnCqnlxVs1TKOPOUqD2NZRAdsKunp+ywNrvGdD43xWONcriyvr
 2KW0nb+mH3RRk8HQzKjfqsVhLMoR7n1MD/+tg8ME8usLn1ik0hBerT56CX0Wh/yQ
 VnOUX6xqlaRydeJJgCUyByz3+jJVvj8sk/VZbr19F0p9id6wpiPQeNus2AcoHFKW
 OyvWcfxzqKegXrYtMsy8IoFzx73zJaXV3ht0I09rhAj3JkdF7vFEIUpKIhsWqxAK
 yWKKqLcVKga/2Yc8jduI
 =FNDd
 -----END PGP SIGNATURE-----

Merge tag 'arc-4.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

Pull ARC fixes from Vineet Gupta:
 "I've been sitting on some of these fixes for a while.

   - Corner case of returning to delay slot from interrupt
   - Changing default interrupt prioiry level
   - Kconfig'ize support for super pages
   - Other minor fixes"

* tag 'arc-4.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: mm: Introduce explicit super page size support
  ARCv2: intc: Allow interruption by lowest priority interrupt
  ARCv2: Check for LL-SC livelock only if LLSC is enabled
  ARC: shrink cpuinfo by not saving full timer BCR
  ARCv2: clocksource: Rename GRTC -> GFRC ...
  ARCv2: STAR 9000950267: Handle return from intr to Delay Slot #2
2016-02-13 08:18:21 -08:00
Vineet Gupta dec2b2849c ARCv2: intc: Allow interruption by lowest priority interrupt
ARC HS Cores support configurable multiple interrupt priorities of upto
16 levels.

There is processor "interrupt preemption threshhold" in STATUS32.E[4:1]
And several places need to set this up:
1. seed value as kernel is booting
2. seed value for user space programs
3. Arg to SLEEP instruction in idle task (what interrupt prio can wake)
4. Per-IRQ line prioirty (i.e. what is the priority of interrupt
   raised by a peripheral or timer or perf counter...

Currently above sites use the highest priority 0. This can be potential
problem when multiple priorities are supported. e.g. user space could
only be interrupted by P0 interrupt, not others...
So turn this over and instead make default interruption level to be
the lowest priority possible 15. This should be fine even if there are
fewer priority levels configured (say two: P0 HIGH, P1 LOW)

This feature also effectively disables FIRQ feature if present in
hardware config. With old code, a P0 interrupt would be FIRQ, needing
special handling (ISR or Register Banks) which is NOT supported yet.
Now it not be P0 (P15 or whatever is lowest prio) so FIRQ is not
triggered.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-10 06:38:50 +05:30
Vineet Gupta 4d0cb15fcc ARCv2: Check for LL-SC livelock only if LLSC is enabled
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-01-29 16:51:04 +05:30
Vineet Gupta b89bd1f4fb ARC: shrink cpuinfo by not saving full timer BCR
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-01-29 16:51:03 +05:30
Vineet Gupta d584f0fb04 ARCv2: clocksource: Rename GRTC -> GFRC ...
... it is now called Global Free Running Counter

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-01-29 16:51:02 +05:30
Vineet Gupta cbfe74a753 ARCv2: STAR 9000950267: Handle return from intr to Delay Slot #2
Returning to delay slot, riding an interrupti, had one loose end.
AUX_USER_SP used for restoring user mode SP upon RTIE was not being
setup from orig task's saved value, causing task to use wrong SP,
leading to ProtV errors.

The reason being:
 - INTERRUPT_EPILOGUE returns to a kernel trampoline, thus not expected to restore it
 - EXCEPTION_EPILOGUE is not used at all

Fix that by restoring AUX_USER_SP explicitly in the trampoline.

This was broken in the original workaround, but the error scenarios got
reduced considerably since v3.14 due to following:

 1. The Linuxthreads.old based userspace at the time caused many more
    exceptions in delay slot than the current NPTL based one.
    Infact with current userspace the error doesn't happen at all.

 2. Return from interrupt (delay slot or otherwise) doesn't get exercised much
    after commit 4de0e52867 ("Really Re-enable interrupts to avoid deadlocks")
    since IRQ_ACTIVE.active being clear means most returns are as if from pure
    kernel (even for active interrupts)

Infact the issue only happened in an experimental branch where I was tinkering with
reverted 4de0e52867

Cc: stable@kernel.org # v4.2+
Fixes: 4255b07f2c ("ARCv2: STAR 9000793984: Handle return from intr to Delay Slot")
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-01-22 17:25:03 +05:30
Linus Torvalds 0f0836b7eb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull livepatching updates from Jiri Kosina:

 - RO/NX attribute fixes for patch module relocations from Josh
   Poimboeuf.  As part of this effort, module.c has been cleaned up as
   well and livepatching is piggy-backing on this cleanup.  Rusty is OK
   with this whole lot going through livepatching tree.

 - symbol disambiguation support from Chris J Arges.  That series is
   also

        Reviewed-by: Miroslav Benes <mbenes@suse.cz>

   but this came in only after I've alredy pushed out.  Didn't want to
   rebase because of that, hence I am mentioning it here.

 - symbol lookup fix from Miroslav Benes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: Cleanup module page permission changes
  module: keep percpu symbols in module's symtab
  module: clean up RO/NX handling.
  module: use a structure to encapsulate layout.
  gcov: use within_module() helper.
  module: Use the same logic for setting and unsetting RO/NX
  livepatch: function,sympos scheme in livepatch sysfs directory
  livepatch: add sympos as disambiguator field to klp_reloc
  livepatch: add old_sympos as disambiguator field to klp_func
2016-01-14 16:38:02 -08:00
Vineet Gupta 6b538db7c6 ARC: dw2 unwind: Catch Dwarf SNAFUs early
Instead of seeing empty stack traces, let kernel fail early so dwarf
issues can be fixed sooner

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-21 14:01:49 +05:30
Vineet Gupta 6d0d506012 ARC: dw2 unwind: Don't bail for CIE.version != 1
The rudimentary CIE.version == 3 handling is already present in code
(for return address register specification)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-21 14:01:25 +05:30
Vineet Gupta 2d64affc92 Revert "ARC: dw2 unwind: Ignore CIE version !=1 gracefully instead of bailing"
Blingly ignoring CIE.version != 1 was a bad idea.
It still leaves "desirability" when running perf with callgraphing where libgcc
symbols might show in hotspot.

More importantly, basic CIE.version == 3 support already exists in code:

|
|   retAddrReg = state.version <= 1 ? *ptr++ : get_uleb128(&ptr, end);
|

Next commit with simply add continue-not-bail for CIE.version != 1

This reverts commit 323f41f9e7.
2015-12-21 13:29:44 +05:30
Vineet Gupta 575a9d4e2c ARC: smp: Rename platform hook @init_cpu_smp -> @init_per_cpu
Makes it similar to smp_ops which also has callback with same name

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-17 12:56:56 +05:30
Noam Camus b474a02382 ARC: rename smp operation init_irq_cpu() to init_per_cpu()
This will better reflect its description i.e. "any needed setup..."
and not just do an "IPI request".

Signed-off-by: Noam Camus <noamc@ezchip.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-17 12:56:43 +05:30
Vineet Gupta 323f41f9e7 ARC: dw2 unwind: Ignore CIE version !=1 gracefully instead of bailing
ARC dwarf unwinder only supports CIE version == 1
The boot time dwarf sanitizer (part of binary lookup table constructor)
would simply bail if it saw CIE version == 3, rendering unwinder with a
NULL lookup table.

It seems libgcc linked with kernel does have such entries.

With fallback linear search removed, and a NULL binary lookup table,
unwinder fails to generate any stack trace.

So allow graceful ignoring of unsupported CIE entries.

This problem was initially seen in Alexey's setup (and not mine) as he
was using buildroot built toolchain (libgcc) which doesn't get built with
CFLAGS_FOR_TARGET="-gdwarf-2 which is my default

Fixes STAR 9000985048: "kernel unwinder broken with stock tools"

Fixes: 2e22502c08 ARC: dw2 unwind: Remove falllback linear search thru FDE entries
Reported-by Alexey Brodkin <abrodkin@synopsys.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-17 11:10:23 +05:30
Vineet Gupta bc79c9a721 ARC: dw2 unwind: Reinstante unwinding out of modules
The fix which removed linear searching of dwarf (because binary lookup
data always exists) missed out on the fact that modules don't get the
binary lookup tables info. This caused unwinding out of modules to stop
working.

So add binary lookup header setup (equivalent of eh_frame_hdr setup) to
modules as well.

While at it, confine the header setup to within unwinder code,
reducing one API exposed out of unwinder code.

Fixes: 2e22502c08 ARC: dw2 unwind: Remove falllback linear search thru FDE entries
Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-17 11:10:23 +05:30
Vineet Gupta c512c6ba7a ARC: intc: Document arc_request_percpu_irq() better
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-12 16:04:12 +05:30
Vineet Gupta c6317bc7c5 ARCv2: perf: Ensure perf intr gets enabled on all cores
This was the second perf intr issue

perf sampling on multicore requires intr to be enabled on all cores.
ARC perf probe code used helper arc_request_percpu_irq() which calls
 - request_percpu_irq() on core0
 - enable_percpu_irq() on all all cores (including core0)

genirq requires that request be made ahead of enable call.
However if perf probe happened on non core0 (observed on a 3.18 kernel),
enable would get called ahead of request, failing obviously and
rendering perf intr disabled on all such cores

[   11.120000] 1 ARC perf       : 8 counters (48 bits), 113 conditions, [overflow IRQ support]
[   11.130000] 1 -----> enable_percpu_irq() IRQ 20 failed
[   11.140000] 3 -----> enable_percpu_irq() IRQ 20 failed
[   11.140000] 2 -----> enable_percpu_irq() IRQ 20 failed
[   11.140000] 0 =====> request_percpu_irq() IRQ 20
[   11.140000] 0 -----> enable_percpu_irq() IRQ 20

Fix this fragility, by calling request_percpu_irq() on whatever core
calls probe (there is no requirement on which core calls this anyways)
and then calling enable on each cores.

Interestingly this started as invesigation of STAR 9000838902:
"sporadically IRQs enabled on perf prob"

which was about occassional boot spew as request_percpu_irq got called
non-locally (from an IPI), and re-enabled interrupts in following path
proc_mkdir ->  spin_unlock_irq()

which the irq work code didn't like.

| ARC perf     : 8 counters (48 bits), 113 conditions, [overflow IRQ support]
|
| BUG: failure at ../kernel/irq_work.c:135/irq_work_run_list()!
| CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.18.10-01127-g285efb8e66d1 #2
|
| Stack Trace:
|  arc_unwind_core.constprop.1+0x94/0x104
|  dump_stack+0x62/0x98
|  irq_work_run_list+0xb0/0xb4
|  irq_work_run+0x22/0x3c
|  do_IPI+0x74/0x9c
|  handle_irq_event_percpu+0x34/0x164
|  handle_percpu_irq+0x58/0x78
|  generic_handle_irq+0x1e/0x2c
|  arch_do_IRQ+0x3c/0x60
|  ret_from_exception+0x0/0x8

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: <stable@vger.kernel.org> #4.2+
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-12 16:03:59 +05:30
Vineet Gupta 5bf704c204 ARC: intc: No need to clear IRQ_NOAUTOEN
arc_request_percpu_irq() is called by all cores to request/enable percpu
irq. It has some "prep" calls needed by genirq:
 - setup percpu devid
 - disable IRQ_NOAUTOEN

However given that enable_percpu_irq() is called enayways, latter can be
avoided.

We are now left with irq_set_percpu_devid() quirk and that too for
ARCompact builds only, since previous patch updated ARCv2 intc to do this
in the "right" place, i.e. irq map function.

By next release, this will ultimately be fixed for ARCompact as well.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-12 16:03:59 +05:30
Vineet Gupta 8eb0984bf4 ARCv2: intc: Fix random perf irq disabling in SMP setup
As part of fixing another perf issue, observed that after a perf run,
the interrupt got disabled on one/more cores.

Turns out that despite requesting perf irq as percpu, the flow handler
registered was not handle_percpu_irq()

Given that on ARCv2 cores, IRQs < 24 are always private to cpu, we
register the right handler at the very onset.

Before Fix

| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0      0      0       0  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0    522      8    51916  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0    522      8   104368  ARCv2 core Intc  20 ARC perf counters

After Fix

| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0      0      0       0  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:  64198  62012  62697  67803  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20: 126014 122792 123301 133654  ARCv2 core Intc  20 ARC perf counters

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: stable@vger.kernel.org #4.2+
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-12 16:03:41 +05:30
Rusty Russell 7523e4dc50 module: use a structure to encapsulate layout.
Makes it easier to handle init vs core cleanly, though the change is
fairly invasive across random architectures.

It simplifies the rbtree code immediately, however, while keeping the
core data together in the same cachline (now iff the rbtree code is
enabled).

Acked-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2015-12-04 22:46:25 +01:00
Vineet Gupta 2e22502c08 ARC: dw2 unwind: Remove falllback linear search thru FDE entries
Fixes STAR 9000953410: "perf callgraph profiling causing RCU stalls"

| perf record -g -c 15000 -e cycles /sbin/hackbench
|
| INFO: rcu_preempt self-detected stall on CPU
| 1: (1 GPs behind) idle=609/140000000000002/0 softirq=2914/2915 fqs=603
| Task dump for CPU 1:

in-kernel dwarf unwinder has a fast binary lookup and a fallback linear
search (which iterates thru each of ~11K entries) thus takes 2 orders of
magnitude longer (~3 million cycles vs. 2000). Routines written in hand
assembler lack dwarf info (as we don't support assembler CFI pseudo-ops
yet) fail the unwinder binary lookup, hit linear search, failing
nevertheless in the end.

However the linear search is pointless as binary lookup tables are created
from it in first place. It is impossible to have binary lookup fail while
succeed the linear search. It is pure waste of cycles thus removed by
this patch.

This manifested as RCU stalls / NMI watchdog splat when running
hackbench under perf with callgraph profiling. The triggering condition
was perf counter overflowing in routine lacking dwarf info (like memset)
leading to patheic 3 million cycle unwinder slow path and by the time it
returned new interrupts were already pending (Timer, IPI) and taken
rightaway. The original memset didn't make forward progress, system kept
accruing more interrupts and more unwinder delayes in a vicious feedback
loop, ultimately triggering the NMI diagnostic.

Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-23 21:36:49 +05:30
Vineet Gupta e81b75f7b2 ARC: remove SYNC from __switch_to()
SYNC in __switch_to() is a historic relic and not needed at all.

 - In UP context it is obviously useless, why would we want to stall
   the core for all updates to stack memory of t0 to complete before
   loading kernel mode callee registers from t1 stack's memory.

 - In SMP, there could be potential race in which outgoing task could
   be concurrently picked for running on a different core, thus writes
   to stack here need to be visible before the reads from stack on
   other core. Peter confirmed that generic schedular already has needed
   barriers (by way of rq lock) so there is no need for additional arch
   barrier.

This came up when Noam was trying to replace this SYNC with EZChip
specific hardware thread scheduling instruction for their platform
support.

Link: http://lkml.kernel.org/r/20151102092654.GM17308@twins.programming.kicks-ass.net
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Cc: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-17 22:05:30 +05:30
Vineet Gupta 512b5b89b9 ARC: Abstract out ISA specific SLEEP args
No semantical changes, prepares for ARCv2 specific change in next commit

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-16 14:17:02 +05:30
Vineet Gupta 541366da6a ARC: [arcompact] Handle bus error from userspace as Interrupt not exception
Bus errors from userspace on ARCompact based cores are handled by core
as a high priority L2 interrupt but current code treated it as interrupt
Handling an interrupt like exception is certainly not going to go unnoticed.
(and it worked so far as we never saw a Bus error from userspace until
IPPK guys tested a DDR controller with ECC error detection etc hence
needed to explicitly trigger/handle such errors)

 - So move mem_service exception handler from common code into ARCv2 code.
 - In ARCompact code, define  mem_service as L2 interrupt handler which
   just drops down to pure kernel mode and goes of to enqueue SIGBUS

Reported-by: Nelson Pereira <npereira@synopsys.com>
Tested-by: Ana Martins <amartins@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-14 13:12:20 +05:30
Vineet Gupta 483bcc99c0 ARC: boot: Non Master cpus only need to call EARLY_CPU_SETUP once
With prev fixes, all cores now start via common entry point @stext which
already calls EARLY_CPU_SETUP for all cores - so no need to invoke it
again

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:42 +05:30
Vineet Gupta aa0efcde45 ARCv2: smp: [plat-*]: No need to explicitly call mcip_init_smp()
MCIP now registers it's own per cpu setup routine (for IPI IRQ request)
using smp_ops.init_irq_cpu().

So no need for platforms to do that. This now completely decouples
platforms from MCIP.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:41 +05:30
Vineet Gupta 286130ebf1 ARC: smp: Introduce smp hook @init_irq_cpu called for all cores
Note this is not part of platform owned static machine_desc,
but more of device owned plat_smp_ops (rather misnamed) which a IPI
provider or some such typically defines.

This will help us seperate out the IPI registration from platform
specific init_cpu_smp() into device specific init_irq_cpu()

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:41 +05:30
Vineet Gupta 8721a7f5a6 ARC: smp: Rename platform hook @init_smp -> @init_cpu_smp
This conveys better that it is called for each cpu

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:40 +05:30
Vineet Gupta 26b8f99623 ARCv2: smp: [plat-*]: No need to explicitly call mcip_init_early_smp()
MCIP now registers it's own probe callback with smp_ops.init_early_smp()
which is called by ARC common code, so no need for platforms to do that.

This decouples the platforms and MCIP and helps confine MCIP details
to it's own file.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:40 +05:30
Vineet Gupta e55af4da02 ARC: smp: Introduce smp hook @init_early_smp for Master core
This adds a platform agnostic early SMP init hook which is called on
Master core before calling setup_processor()

  setup_arch()
     smp_init_cpus()
         smp_ops.init_early_smp()
     ...
     setup_processor()

How this helps:
 - Used for one time init of certain SMP centric IP blocks, before
   calling setup_processor() which probes various bits of core,
   possibly including this block

 - Currently platforms need to call this IP block init from their
   init routines, which doesn't make sense as this is specific to ARC
   core and not platform and otherwise requires copy/paste in all
   (and hence a possible point of failure)

e.g. MCIP init is called from 2 platforms currently (axs10x and sim)
which will go away once we have this.

This change only adds the hooks but they are empty for now. Next commit
will populate them and remove the explicit init calls from platforms.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:40 +05:30
Vineet Gupta 4c82f28617 ARC: remove @init_time, @init_irq platform callbacks
These are not in use for ARC platforms. Moreover DT mechanims exist to
probe them w/o explicit platform calls.

 - clocksource drivers can use CLOCKSOURCE_OF_DECLARE()
 - intc IRQCHIP_DECLARE() calls + cascading inside DT allows external
   intc to be probed automatically

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:39 +05:30
Vineet Gupta e0868e6f67 ARC: smp: irqchip: handle IPI as percpu irq like timer
The reason this was not done so far was lack of genuine IPI_IRQ for
ARC700, as we don't have a SMP version of core yet (which might change
soon thx to EZChip). Nevertheles to increase the build coverage, we
need to allow CONFIG_SMP for ARC700 and still be able to run it on a
UP platform (nsim or AXS101) with a UP Device Tree (SMP-on-UP)

The build itself requires some define for IPI_IRQ and even a dummy
value is fine since that code won't run anyways.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:39 +05:30
Vineet Gupta 3971cdc202 ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes
For Run-on-reset, non masters need to spin wait. For Halt-on-reset they
can jump to entry point directly.

Also while at it, made reset vector handler as "the" entry point for
kernel including host debugger based boot (which uses the ELF header
entry point)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:08:17 +05:30
Vineet Gupta f33e9c434b ARC: smp: Move default boot kick/wait code out of MCIP into common code
For non halt-on-reset case, all cores start of simultaneously in @stext.
Master core0 proceeds with kernel boot, while other spin-wait on
@wake_flag being set by master once it is ready. So NO hardware assist
is needed for master to "kick" the others.

This patch moves this soft implementation out of mcip.c (as there is no
hardware assist) into common smp.c

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-17 17:48:27 +05:30