On Sat, Jan 16, 2021 at 12:57 AM 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. > > While at it, provide __dtb_start as a parameter to setup_vm() in > BUILTIN_DTB case, so we don't have to duplicate BUILTIN_DTB specific > processing in MMU-enabled and MMU-disabled versions of setup_vm(). @Palmer: ping :) > Signed-off-by: Vitaly Wool <vitaly.wool@xxxxxxxxxxxx> While at it, since this is just a respin/concatenation: @Damien: are you okay with re-adding 'Tested-By:' ? @Anup: are you okay with adding 'Reviewed-by:' since you have reviewed both v1 patches that were concatenated? Best regards, Vitaly > --- > Changes from v2: > * folded "RISC-V: simplify BUILTIN_DTB processing" patch > [http://lists.infradead.org/pipermail/linux-riscv/2021-January/004153.html] > Changes from v1: > * no direct initial_boot_params assignment > * skips the temporary mapping for DT if BUILTIN_DTB=y > > arch/riscv/Kconfig | 1 - > arch/riscv/kernel/head.S | 4 ++++ > arch/riscv/mm/init.c | 19 +++++++++++++------ > 3 files changed, 17 insertions(+), 7 deletions(-) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index 2ef05ef921b5..444a1ed1e847 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -445,7 +445,6 @@ endmenu > > config BUILTIN_DTB > def_bool n > - depends on RISCV_M_MODE > depends on OF > > menu "Power management options" > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S > index 16e9941900c4..f5a9bad86e58 100644 > --- a/arch/riscv/kernel/head.S > +++ b/arch/riscv/kernel/head.S > @@ -260,7 +260,11 @@ clear_bss_done: > > /* Initialize page tables and relocate to virtual addresses */ > la sp, init_thread_union + THREAD_SIZE > +#ifdef CONFIG_BUILTIN_DTB > + la a0, __dtb_start > +#else > mv a0, s1 > +#endif /* CONFIG_BUILTIN_DTB */ > call setup_vm > #ifdef CONFIG_MMU > la a0, early_pg_dir > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > index 30b61f2c6b87..45faad7c4291 100644 > --- a/arch/riscv/mm/init.c > +++ b/arch/riscv/mm/init.c > @@ -192,10 +192,13 @@ 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; > > @@ -604,11 +615,7 @@ static void __init setup_vm_final(void) > #else > asmlinkage void __init setup_vm(uintptr_t dtb_pa) > { > -#ifdef CONFIG_BUILTIN_DTB > - dtb_early_va = (void *) __dtb_start; > -#else > dtb_early_va = (void *)dtb_pa; > -#endif > dtb_early_pa = dtb_pa; > } > > -- > 2.20.1 >
