As of 93917ad509 ("RISC-V: Add support for restartable sequence") we
have support for restartable sequences, which default to enabled. These
select MEMBARRIER, so disabling it is now redundant.
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>
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>
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>
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>
Add jump-label implementation based on the ARM64 version
and add CONFIG_JUMP_LABEL=y to the defconfigs.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Reviewed-by: Björn Töpel <bjorn.topel@gmail.com>
Tested-by: Björn Töpel <bjorn.topel@gmail.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>
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>
