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-rc1 and tested on SiFive Unleashed board and QEMU virt machine. It can also be found in riscv_setup_vm_v2 branch of https//github.com/avpatel/linux.git 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 (5): RISC-V: Add separate defconfig for 32bit systems RISC-V: Make setup_vm() independent of GCC code model RISC-V: Allow booting kernel from any 4KB aligned address RISC-V: Remove redundant trampoline page table RISC-V: Fix memory reservation in setup_bootmem() arch/riscv/Kconfig | 11 + 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 | 6 +- arch/riscv/kernel/head.S | 15 +- arch/riscv/kernel/setup.c | 4 +- arch/riscv/mm/init.c | 391 +++++++++++++++++++++++----- 8 files changed, 450 insertions(+), 71 deletions(-) create mode 100644 arch/riscv/configs/rv32_defconfig -- 2.17.1
