On Mon, Jan 4, 2021 at 6:15 PM Vitaly Wool <vitaly.wool@xxxxxxxxxxxx> wrote: > > Sometimes, especially in a production system we may not want to > use a "smart bootloader" like u-boot to load kernel, ramdisk and > device tree from a filesystem on eMMC, but rather load the kernel > from a NAND partition and just run it as soon as we can, and in > this case it is convenient to have device tree compiled into the > kernel binary. Since this case is not limited to MMU-less systems, > let's support it for these which have MMU enabled too. > > Signed-off-by: Vitaly Wool <vitaly.wool@xxxxxxxxxxxx> > --- > Changelog from v1: > * no direct initial_boot_params assignment > * skips the temporary mapping for DT if BUILTIN_DTB=y > > arch/riscv/Kconfig | 1 - > arch/riscv/mm/init.c | 15 +++++++++++++-- > 2 files changed, 13 insertions(+), 3 deletions(-) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index 81b76d44725d..07a8bdcc423f 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -416,7 +416,6 @@ endmenu > > config BUILTIN_DTB > def_bool n > - depends on RISCV_M_MODE > depends on OF > > menu "Power management options" > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > index 13ba533f462b..04aeee276817 100644 > --- a/arch/riscv/mm/init.c > +++ b/arch/riscv/mm/init.c > @@ -191,10 +191,13 @@ void __init setup_bootmem(void) > #endif /* CONFIG_BLK_DEV_INITRD */ > > /* > - * Avoid using early_init_fdt_reserve_self() since __pa() does > + * If DTB is built in, no need to reserve its memblock. > + * Otherwise, do reserve it but avoid using > + * early_init_fdt_reserve_self() since __pa() does > * not work for DTB pointers that are fixmap addresses > */ > - 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)); > > early_init_fdt_scan_reserved_mem(); > dma_contiguous_reserve(dma32_phys_limit); > @@ -499,6 +502,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) > /* Setup early PMD for DTB */ > create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA, > (uintptr_t)early_dtb_pmd, PGDIR_SIZE, PAGE_TABLE); > +#ifndef CONFIG_BUILTIN_DTB > /* Create two consecutive PMD mappings for FDT early scan */ > pa = dtb_pa & ~(PMD_SIZE - 1); > create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA, > @@ -506,7 +510,11 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) > create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA + PMD_SIZE, > pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL); > dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PMD_SIZE - 1)); > +#else /* CONFIG_BUILTIN_DTB */ > + dtb_early_va = __va(dtb_pa); > +#endif /* CONFIG_BUILTIN_DTB */ > #else > +#ifndef CONFIG_BUILTIN_DTB > /* Create two consecutive PGD mappings for FDT early scan */ > pa = dtb_pa & ~(PGDIR_SIZE - 1); > create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA, > @@ -514,6 +522,9 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) > create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA + PGDIR_SIZE, > pa + PGDIR_SIZE, PGDIR_SIZE, PAGE_KERNEL); > dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PGDIR_SIZE - 1)); > +#else /* CONFIG_BUILTIN_DTB */ > + dtb_early_va = __va(dtb_pa); > +#endif /* CONFIG_BUILTIN_DTB */ > #endif > dtb_early_pa = dtb_pa; > > -- > 2.20.1 > Looks good to me. Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx> Regards, Anup
