From: Alexandre Ghiti alexghiti@rivosinc.com
commit 1b50f956c8fe9082bdee4a9cfd798149c52f7043 upstream.
We used to access the dtb via its linear mapping address but now that the dtb early mapping was moved in the fixmap region, we can keep using this address since it is present in swapper_pg_dir, and remove the dtb relocation.
Note that the relocation was wrong anyway since early_memremap() is restricted to 256K whereas the maximum fdt size is 2MB.
Signed-off-by: Alexandre Ghiti alexghiti@rivosinc.com Reviewed-by: Conor Dooley conor.dooley@microchip.com Tested-by: Conor Dooley conor.dooley@microchip.com Link: https://lore.kernel.org/r/20230329081932.79831-4-alexghiti@rivosinc.com Cc: stable@vger.kernel.org # 5.15.x Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/riscv/mm/init.c | 21 ++------------------- 1 file changed, 2 insertions(+), 19 deletions(-)
--- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -229,25 +229,8 @@ static void __init setup_bootmem(void) * early_init_fdt_reserve_self() since __pa() does * not work for DTB pointers that are fixmap addresses */ - if (!IS_ENABLED(CONFIG_BUILTIN_DTB)) { - /* - * In case the DTB is not located in a memory region we won't - * be able to locate it later on via the linear mapping and - * get a segfault when accessing it via __va(dtb_early_pa). - * To avoid this situation copy DTB to a memory region. - * Note that memblock_phys_alloc will also reserve DTB region. - */ - if (!memblock_is_memory(dtb_early_pa)) { - size_t fdt_size = fdt_totalsize(dtb_early_va); - phys_addr_t new_dtb_early_pa = memblock_phys_alloc(fdt_size, PAGE_SIZE); - void *new_dtb_early_va = early_memremap(new_dtb_early_pa, fdt_size); - - memcpy(new_dtb_early_va, dtb_early_va, fdt_size); - early_memunmap(new_dtb_early_va, fdt_size); - _dtb_early_pa = new_dtb_early_pa; - } else - memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va)); - } + if (!IS_ENABLED(CONFIG_BUILTIN_DTB)) + memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
dma_contiguous_reserve(dma32_phys_limit); if (IS_ENABLED(CONFIG_64BIT))