Our nommu_virt_defconfig set SLOB=y and SLAB_MERGE_DEFAULT=n. As of
eb52c0fc23 ("mm: Make SLAB_MERGE_DEFAULT depend on SL[AU]B") it's no
longer necessary to set the second, which appears to never have had any
effect for SLOB=y anyway.
This was suggested by savedefconfig.
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This patchset allows to have a single kernel for sv39 and sv48 without
being relocatable.
The idea comes from Arnd Bergmann who suggested to do the same as x86,
that is mapping the kernel to the end of the address space, which allows
the kernel to be linked at the same address for both sv39 and sv48 and
then does not require to be relocated at runtime.
This implements sv48 support at runtime. The kernel will try to boot
with 4-level page table and will fallback to 3-level if the HW does not
support it. Folding the 4th level into a 3-level page table has almost
no cost at runtime.
Note that kasan region had to be moved to the end of the address space
since its location must be known at compile-time and then be valid for
both sv39 and sv48 (and sv57 that is coming).
* riscv-sv48-v3:
riscv: Explicit comment about user virtual address space size
riscv: Use pgtable_l4_enabled to output mmu_type in cpuinfo
riscv: Implement sv48 support
asm-generic: Prepare for riscv use of pud_alloc_one and pud_free
riscv: Allow to dynamically define VA_BITS
riscv: Introduce functions to switch pt_ops
riscv: Split early kasan mapping to prepare sv48 introduction
riscv: Move KASAN mapping next to the kernel mapping
riscv: Get rid of MAXPHYSMEM configs
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
CONFIG_MAXPHYSMEM_* are actually never used, even the nommu defconfigs
selecting the MAXPHYSMEM_2GB had no effects on PAGE_OFFSET since it was
preempted by !MMU case right before.
In addition, the move of the kernel mapping at the end of the address
space broke the use of MAXPHYSMEM_2G with MMU since it defines PAGE_OFFSET
at the same address as the kernel mapping.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: 2bfc6cd81b ("riscv: Move kernel mapping outside of linear mapping")
Signed-off-by: Alexandre Ghiti <alexandre.ghiti@canonical.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Conor Dooley <Conor.Dooley@microchip.com>
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Pull RISC-V updates from Palmer Dabbelt:
- Support for the DA9063 as used on the HiFive Unmatched.
- Support for relative extables, which puts us in line with other
architectures and save some space in vmlinux.
- A handful of kexec fixes/improvements, including the ability to run
crash kernels from PCI-addressable memory on the HiFive Unmatched.
- Support for the SBI SRST extension, which allows systems that do not
have an explicit driver in Linux to reboot.
- A handful of fixes and cleanups, including to the defconfigs and
device trees.
* tag 'riscv-for-linus-5.17-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (52 commits)
RISC-V: Use SBI SRST extension when available
riscv: mm: fix wrong phys_ram_base value for RV64
RISC-V: Use common riscv_cpuid_to_hartid_mask() for both SMP=y and SMP=n
riscv: head: remove useless __PAGE_ALIGNED_BSS and .balign
riscv: errata: alternative: mark vendor_patch_func __initdata
riscv: head: make secondary_start_common() static
riscv: remove cpu_stop()
riscv: try to allocate crashkern region from 32bit addressible memory
riscv: use hart id instead of cpu id on machine_kexec
riscv: Don't use va_pa_offset on kdump
riscv: dts: sifive: fu540-c000: Fix PLIC node
riscv: dts: sifive: fu540-c000: Drop bogus soc node compatible values
riscv: dts: sifive: Group tuples in register properties
riscv: dts: sifive: Group tuples in interrupt properties
riscv: dts: microchip: mpfs: Group tuples in interrupt properties
riscv: dts: microchip: mpfs: Fix clock controller node
riscv: dts: microchip: mpfs: Fix reference clock node
riscv: dts: microchip: mpfs: Fix PLIC node
riscv: dts: microchip: mpfs: Drop empty chosen node
riscv: dts: canaan: Group tuples in interrupt properties
...
The "k210_generic" DT has been the default in Kconfig since 67d96729a9
("riscv: Update Canaan Kendryte K210 device tree"), so drop it from the
defconfigs to avoid diff with savedefconfig.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
We've always had CONFIG_EFI as "def_bool y" so this has always been
redundant. It's removed by savedefconfig, so drop it to keep things
clean.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
As of ab7fbad0c7 ("riscv: Fix unmet direct dependencies built based on
SOC_VIRT") we select CONFIG_POWER_RESET=y along with CONFIG_SOC_VIRT,
which is already in defconfig. This make setting CONFIG_POWER_RESET in
the defconfigs redundant, so remove it to remain consistent with
savedefconfig.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This should have no functional change, it just sorts CONFIG_BLK_DEV_BSG
the same way savedefconfig does.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This should have no functional change, it just sorts
CONFIG_SURFACE_PLATFORMS the same way savedefconfig does.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This should have no functional change, it just sorts CONFIG_MMC the same
way savedefconfig does. This only touches the rv64 defconfig because
rv32_defconfig was already sorted correctly.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This should have no functional change, it just sorts
CONFIG_PTP_1588_CLOCK the same way savedefconfig does. This only
touches the rv64 defconfig because rv32_defconfig was already sorted
correctly.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This should have no functional change, it just sorts
CONFIG_SOC_POLARFIRE the same way savedefconfig does.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This should have no functional change, it just sorts
CONFIG_SYSFS_SYSCALL the same way savedefconfig does.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This should have no functional change, it just sorts CONFIG_BPF_SYSCALL
the same way savedefconfig does.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
We have CONFIG_FRAMEBUFFER_CONSOLE=y in the defconfigs, but that depends
on CONFIG_FB so it's not actually getting set. I'm assuming most users
on real systems want a framebuffer console, so this enables CONFIG_FB to
allow that to take effect.
Fixes: 33c57c0d3c ("RISC-V: Add a basic defconfig")
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Let's enable KVM RISC-V in RV64 and RV32 defconfigs as module
so that it always built along with the default kernel image.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Both RADEON and NOUVEAU graphics cards are supported on RISC-V. Enabling
the one and not the other does not make sense.
As typically at most one of RADEON, NOUVEAU, or VIRTIO GPU support will be
needed DRM drivers should be compiled as modules.
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Add the ability to do randconfig build targets for both
rv32 and rv64.
Based on a similar patch by Michael Ellerman for PowerPC.
Usage:
make ARCH=riscv rv32_randconfig
or
make ARCH=riscv rv64_randconfig
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The EFI system partition uses the FAT file system. Many distributions add
an entry in /etc/fstab for the ESP. We must ensure that mounting does not
fail.
The default code page for FAT is 437 (cf. CONFIG_FAT_DEFAULT_CODEPAGE).
The default IO character set is "iso8859-1" (cf. CONFIG_NLS_ISO8859_1).
So let's enable NLS_CODEPAGE_437 and NLS_ISO8859_1 in defconfig.
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
NVMe is a non-volatile storage media attached via PCIe.
As NVMe has much higher throughput than other block devices like
SATA it is a must have for RISC-V. Enable CONFIG_BLK_DEV_NVME.
The HiFive Unmatched is a board providing M.2 slots for NVMe drives.
Enable CONFIG_PCIE_FU740.
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The CPU hotplug support has been tested on QEMU, Spike, and SiFive
Unleashed so let's enable it by default in RV32 and RV64 defconfigs.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Pull RISC-V updates from Palmer Dabbelt:
"A handful of new RISC-V related patches for this merge window:
- A check to ensure drivers are properly using uaccess. This isn't
manifesting with any of the drivers I'm currently using, but may
catch errors in new drivers.
- Some preliminary support for the FU740, along with the HiFive
Unleashed it will appear on.
- NUMA support for RISC-V, which involves making the arm64 code
generic.
- Support for kasan on the vmalloc region.
- A handful of new drivers for the Kendryte K210, along with the DT
plumbing required to boot on a handful of K210-based boards.
- Support for allocating ASIDs.
- Preliminary support for kernels larger than 128MiB.
- Various other improvements to our KASAN support, including the
utilization of huge pages when allocating the KASAN regions.
We may have already found a bug with the KASAN_VMALLOC code, but it's
passing my tests. There's a fix in the works, but that will probably
miss the merge window.
* tag 'riscv-for-linus-5.12-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (75 commits)
riscv: Improve kasan population by using hugepages when possible
riscv: Improve kasan population function
riscv: Use KASAN_SHADOW_INIT define for kasan memory initialization
riscv: Improve kasan definitions
riscv: Get rid of MAX_EARLY_MAPPING_SIZE
soc: canaan: Sort the Makefile alphabetically
riscv: Disable KSAN_SANITIZE for vDSO
riscv: Remove unnecessary declaration
riscv: Add Canaan Kendryte K210 SD card defconfig
riscv: Update Canaan Kendryte K210 defconfig
riscv: Add Kendryte KD233 board device tree
riscv: Add SiPeed MAIXDUINO board device tree
riscv: Add SiPeed MAIX GO board device tree
riscv: Add SiPeed MAIX DOCK board device tree
riscv: Add SiPeed MAIX BiT board device tree
riscv: Update Canaan Kendryte K210 device tree
dt-bindings: add resets property to dw-apb-timer
dt-bindings: fix sifive gpio properties
dt-bindings: update sifive uart compatible string
dt-bindings: update sifive clint compatible string
...
The nommu_k210_defconfig default configuration allows booting a Canaan
Kendryte K210 SoC based boards using an embedded intramfs cpio file.
Modifying this configuration to enable support for the board SD card is
not trivial for all users. To help beginners getting started with these
boards, add the nommu_k210_sdcard_defconfig default configuration file
to set all configuration options necessary to use the board mmc-spi sd
card for the root file system.
This new configuration adds support for the block layer, the mmc-spi
driver and modifies the boot options to specify the rootfs device as
mmcblk0p1 (first partition of the sd card block device). The ext2 file
system is selected by default to encourage its use as that results in
only about 4KB added to the kernel image size. As ext2 does not have
journaling, the boot options specify a read-only mount of the file
system. Similarly to the smaller nommu_k210_defconfig, this new default
configuration disables virtual terminal support to reduce the kernel
image size.
The default device tree selected is unchanged, specifying the simple
"k210_generic" device tree file. The user must change this setting to
specify the device tree suitable for the board being used
(sipeed_maix_bit, sipeed_maix_dock, sipeed_maix_go, sipeed_maixduino or
canaan_kd233).
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Update the Kendryte k210 nommu default configuration file
(nommu_k210_defconfig) to include device drivers for reset, reboot,
I2C, SPI, gpio and LEDs support. Virtual Terminal support is also
disabled as no terminal devices are supported and enabled. Disabling
CONFIG_VT (removing the no longer needed override for
CONFIG_VGA_CONSOLE) reduces the kernel image size by about 65 KB.
This default configuration remains suitable for a system using an
initramfs cpio file linked into the kernel image.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Rename configuration options and directories related to the Kendryte
K210 SoC to use the SoC vendor name (canaan) instead of the "kendryte"
branding name.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Ethernet phy VSC8541-01 on HiFive Unleashed has its reset line
connected to a gpio, so enable GPIO driver's required to reset
the phy.
Signed-off-by: Sagar Shrikant Kadam <sagar.kadam@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Add a RISC-V architecture specific stub code that actually copies the
actual kernel image to a valid address and jump to it after boot services
are terminated. Enable UEFI related kernel configs as well for RISC-V.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Link: https://lore.kernel.org/r/20200421033336.9663-4-atish.patra@wdc.com
[ardb: - move hartid fetch into check_platform_features()
- use image_size not reserve_size
- select ISA_C
- do not use dram_base]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
This adds SiFive drivers to rv32_defconfig, to keep in sync with the
64-bit config. This is useful when testing 32-bit kernel with QEMU
'sifive_u' 32-bit machine.
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Right now the RISC-V timer driver is convoluted to support:
1. Linux RISC-V S-mode (with MMU) where it will use TIME CSR for
clocksource and SBI timer calls for clockevent device.
2. Linux RISC-V M-mode (without MMU) where it will use CLINT MMIO
counter register for clocksource and CLINT MMIO compare register
for clockevent device.
We now have a separate CLINT timer driver which also provide CLINT
based IPI operations so let's remove CLINT MMIO related code from
arch/riscv directory and RISC-V timer driver.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Emil Renner Berhing <kernel@esmil.dk>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Update the Kendryte K210 default kernel configuration file
nommu_k210_defconfig to enable builtin DTB by default.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Pull RISC-V updates from Palmer Dabbelt:
"This contains a handful of new features:
- Partial support for the Kendryte K210.
There are still a few outstanding issues that I have patches for,
but I don't actually have a board to test them so they're not
included yet.
- SBI v0.2 support.
- Fixes to support for building with LLVM-based toolchains. The
resulting images are known not to boot yet.
I don't anticipate a part two, but I'll probably have something early
in the RCs to finish up the K210 support"
* tag 'riscv-for-linus-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (38 commits)
riscv: create a loader.bin boot image for Kendryte SoC
riscv: Kendryte K210 default config
riscv: Add Kendryte K210 device tree
riscv: Select required drivers for Kendryte SOC
riscv: Add Kendryte K210 SoC support
riscv: Add SOC early init support
riscv: Unaligned load/store handling for M_MODE
RISC-V: Support cpu hotplug
RISC-V: Add supported for ordered booting method using HSM
RISC-V: Add SBI HSM extension definitions
RISC-V: Export SBI error to linux error mapping function
RISC-V: Add cpu_ops and modify default booting method
RISC-V: Move relocate and few other functions out of __init
RISC-V: Implement new SBI v0.2 extensions
RISC-V: Introduce a new config for SBI v0.1
RISC-V: Add SBI v0.2 extension definitions
RISC-V: Add basic support for SBI v0.2
RISC-V: Mark existing SBI as 0.1 SBI.
riscv: Use macro definition instead of magic number
riscv: Add support to dump the kernel page tables
...
This patch adds a defconfig file to build No-MMU kernels meant for
boards based on the Kendryte K210 SoC.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The kconfig select causes build failues for SOC_VIRT config becaus
we are selecting lot of VIRTIO drivers without selecting all required
dependencies.
Better approach is to only select essential drivers from SOC_VIRT
config option and enable required VIRTIO drivers using defconfigs.
Fixes: 759bdc1681 ("RISC-V: Add kconfig option for QEMU virt machine")
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The SYSCON Reboot and Poweroff drivers can be used on QEMU virt machine
to reboot or poweroff the system hence we select these drivers using
QEMU virt machine kconfig option.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
We have kconfig option for QEMU virt machine so let's enable it
in RV32 and RV64 defconfigs. Also, we remove various VIRTIO configs
from RV32 and RV64 defconfigs because these are now selected by
QEMU virt machine kconfig option.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
According to init/Kconfig:
"sys_sysfs is an obsolete system call no longer supported in libc.
Note that disabling this option is more secure but might break
compatibility with some systems."
This syscall is not required for new architectures. Since the config
defaults to 'y'. Set this to 'n' exlicitly.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Enable more debugging options in the RISC-V defconfigs to help kernel
developers catch problems with patches earlier in the development
cycle.
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
The kernel runs in M-mode without using page tables, and thus can't run
bare metal without help from additional firmware.
Most of the patch is just stubbing out code not needed without page
tables, but there is an interesting detail in the signals implementation:
- The normal RISC-V syscall ABI only implements rt_sigreturn as VDSO
entry point, but the ELF VDSO is not supported for nommu Linux.
We instead copy the code to call the syscall onto the stack.
In addition to enabling the nommu code a new defconfig for a small
kernel image that can run in nommu mode on qemu is also provided, to run
a kernel in qemu you can use the following command line:
qemu-system-riscv64 -smp 2 -m 64 -machine virt -nographic \
-kernel arch/riscv/boot/loader \
-drive file=rootfs.ext2,format=raw,id=hd0 \
-device virtio-blk-device,drive=hd0
Contains contributions from Damien Le Moal <Damien.LeMoal@wdc.com>.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
[paul.walmsley@sifive.com: updated to apply; add CONFIG_MMU guards
around PCI_IOBASE definition to fix build issues; fixed checkpatch
issues; move the PCI_IO_* and VMEMMAP address space macros along
with the others; resolve sparse warning]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
This patch enables more VIRTIO drivers (such as console, rpmsg, 9p,
rng, etc.) which are usable on KVM RISC-V Guest and Xvisor RISC-V
Guest.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alexander Graf <graf@amazon.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Update the defconfig:
- Add CONFIG_HW_RANDOM=y and CONFIG_HW_RANDOM_VIRTIO=y to enable
VirtIORNG when running on QEMU
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Update the rv32_defconfig:
- Add 'CONFIG_DEVTMPFS_MOUNT=y' to match the RISC-V defconfig
- Add CONFIG_HW_RANDOM=y and CONFIG_HW_RANDOM_VIRTIO=y to enable
VirtIORNG when running on QEMU
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Align the RV64 defconfig to the output of "make savedefconfig" to
avoid unnecessary deltas for future defconfig patches. This patch
should have no runtime functional impact.
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Enable SOC_SIFIVE so the default upstream config is bootable on the SiFive
Unleashed Board.
And have basic support for future boards based on the same SoC.
Signed-off-by: Loys Ollivier <lollivier@baylibre.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
[paul.walmsley@sifive.com: updated to apply]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
This patch enables NO_HZ_IDLE (idle dynamic ticks) and HIGH_RES_TIMERS
(hrtimers) in RV32 and RV64 defconfigs.
Both of the above options are enabled by default for architectures
such as x86, ARM, and ARM64.
The idle dynamic ticks helps use save power by stopping timer ticks
when the system is idle whereas hrtimers is a much improved timer
subsystem compared to the old "timer wheel" based system.
This patch is tested on SiFive Unleashed board and QEMU Virt machine.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
