[v3,0/4] Boot RISC-V kernel from any 4KB aligned address

Message

Anup Patel March 25, 2019, 9:22 a.m. UTC

This patchset primarily extends initial page table setup using fixmap
to boot Linux RISC-V kernel (64bit and 32bit) from any 4KB aligned address.

We also add 32bit defconfig to allow people to try 32bit Linux RISC-V
kernel as well.

The patchset is based on Linux-5.1-rc2 and tested on SiFive Unleashed
board and QEMU virt machine.

It can also be found in riscv_setup_vm_v3 branch of
https//github.com/avpatel/linux.git

Changes since v2:
- Dropped PATCH2 because we have separate fix for Linux-5.1-rcX
- Moved PATCH5 to PATCH2
- Moved PATCH4 to PATCH3
- The "Booting kernel from any 4KB aligned address" is now PATCH4

Changes since v1:
- Add kconfig option BOOT_PAGE_ALIGNED to enable 4KB aligned booting
- Improved initial page table setup code to select best/biggest
  possible mapping size based on load address alignment
- Added PATCH4 to remove redundant trampoline page table
- Added PATCH5 to fix memory reservation in setup_bootmem()

Anup Patel (4):
  RISC-V: Add separate defconfig for 32bit systems
  RISC-V: Fix memory reservation in setup_bootmem()
  RISC-V: Remove redundant trampoline page table
  RISC-V: Allow booting kernel from any 4KB aligned address

 arch/riscv/Kconfig                  |  12 +
 arch/riscv/configs/rv32_defconfig   |  84 +++++++
 arch/riscv/include/asm/fixmap.h     |   5 +
 arch/riscv/include/asm/pgtable-64.h |   5 +
 arch/riscv/include/asm/pgtable.h    |   5 +
 arch/riscv/kernel/head.S            |  14 +-
 arch/riscv/kernel/setup.c           |   4 +-
 arch/riscv/mm/init.c                | 376 +++++++++++++++++++++++-----
 8 files changed, 430 insertions(+), 75 deletions(-)
 create mode 100644 arch/riscv/configs/rv32_defconfig