On Sat, Dec 26, 2020 at 10:03 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> > --- > arch/riscv/Kconfig | 1 - > arch/riscv/mm/init.c | 12 ++++++++++-- > 2 files changed, 10 insertions(+), 3 deletions(-) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index 2b41f6d8e458..9464b4e3a71a 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -419,7 +419,6 @@ 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 87c305c566ac..5d1c7a3ec01c 100644 > --- a/arch/riscv/mm/init.c > +++ b/arch/riscv/mm/init.c > @@ -194,12 +194,20 @@ void __init setup_bootmem(void) > setup_initrd(); > #endif /* CONFIG_BLK_DEV_INITRD */ > > + /* > + * If DTB is built in, no need to reserve its memblock. > + * OTOH, initial_boot_params has to be set to properly copy DTB > + * before unflattening later on. > + */ > + if (IS_ENABLED(CONFIG_BUILTIN_DTB)) > + initial_boot_params = __va(dtb_early_pa); Don't assign initial_boot_params directly here because the early_init_dt_scan() will do it. The setup_vm() is supposed to setup dtb_early_va and dtb_early_pa for MMU-enabled case so please add a "#ifdef" over there for the built-in DTB case. > + else > + memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va)); > + > /* > * Avoid using early_init_fdt_reserve_self() since __pa() does > * not work for DTB pointers that are fixmap addresses > */ This comment needs to be updated and moved along the memblock_reserve() statement. > - memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va)); > - > early_init_fdt_scan_reserved_mem(); > dma_contiguous_reserve(dma32_phys_limit); > memblock_allow_resize(); > -- > 2.29.2 > This patch should be based upon Damiens builtin DTB patch. Refer, https://www.spinics.net/lists/linux-gpio/msg56616.html Regards, Anup
