Simon, This looks ok to me, but I haven't been involved with the bootm code much. Can you taker a quick look?
On Wed, 22 Apr 2026 at 20:10, <[email protected]> wrote: > > From: Randolph Sapp <[email protected]> > > Add a free flag and an initial call to free allocations covered by the > global FDT. This assumes that all calls to boot_fdt_add_mem_rsv_regions > occur before the transition to the new device tree, thus we can access > the currently active device tree through the global data pointer. > > This allows us to clearly indicate to the user when a device tree > reservation fails. How we handle this can still use some improvement. > Right now we'll keep the default behavior and try to boot anyway. > > This functionality was broken in: > 5a6aa7d ("boot: fdt: Handle already reserved memory in > boot_fdt_reserve_region()") > [...] either operation. > + */ > +static void boot_fdt_reserve_region(u64 addr, u64 size, u32 flags, bool free) > { The function name is not accurate anymore. Perhaps call it boot_fdt_handle_region()? > long ret; > phys_addr_t rsv_addr; > > rsv_addr = (phys_addr_t)addr; > - ret = lmb_alloc_mem(LMB_MEM_ALLOC_ADDR, 0, &rsv_addr, size, flags); > + if (free) > + ret = lmb_free(rsv_addr, size, flags); > + else > + ret = lmb_alloc_mem(LMB_MEM_ALLOC_ADDR, 0, &rsv_addr, size, > + flags); > + > if (!ret) { > - debug(" reserving fdt memory region: addr=%llx size=%llx > flags=%x\n", > - (unsigned long long)addr, > + debug(" %s fdt memory region: addr=%llx size=%llx > flags=%x\n", > + free ? "freed" : "reserved", (unsigned long long)addr, > (unsigned long long)size, flags); > - } else if (ret != -EEXIST && ret != -EINVAL) { > - puts("ERROR: reserving fdt memory region failed "); > - printf("(addr=%llx size=%llx flags=%x)\n", > - (unsigned long long)addr, > - (unsigned long long)size, flags); > + } else { > + printf("ERROR: %s fdt memory region failed (addr=%llx > size=%llx flags=%x): %ld\n", > + free ? "freeing" : "reserving", (unsigned long > long)addr, > + (unsigned long long)size, flags, ret); > } > } > > /** > - * boot_fdt_add_mem_rsv_regions - Mark the memreserve and reserved-memory > - * sections as unusable > + * boot_fdt_add_mem_rsv_regions - Handle FDT memreserve and reserved-memory > + * sections > * @fdt_blob: pointer to fdt blob base address > + * @free: indicate if regions are being freed > * > - * Adds the and reserved-memorymemreserve regions in the dtb to the lmb > block. > - * Adding the memreserve regions prevents u-boot from using them to store the > - * initrd or the fdt blob. > + * Adds or removes reserved-memory and memreserve regions in the dtb to the > lmb > + * block. Adding the memreserve regions prevents u-boot from using them to > store > + * the initrd or the fdt blob. This function will attempt to clean the > currently > + * active reservations if a new device tree blob is given. > */ > -void boot_fdt_add_mem_rsv_regions(void *fdt_blob) > +void boot_fdt_add_mem_rsv_regions(void *fdt_blob, bool free) > { > uint64_t addr, size; > int i, total, ret; > @@ -108,12 +124,16 @@ void boot_fdt_add_mem_rsv_regions(void *fdt_blob) > if (fdt_check_header(fdt_blob) != 0) > return; > > + /* Remove old regions */ > + if (gd->fdt_blob != fdt_blob) > + boot_fdt_add_mem_rsv_regions((void *)gd->fdt_blob, true); > + > /* process memreserve sections */ > total = fdt_num_mem_rsv(fdt_blob); > for (i = 0; i < total; i++) { > if (fdt_get_mem_rsv(fdt_blob, i, &addr, &size) != 0) > continue; > - boot_fdt_reserve_region(addr, size, LMB_NOOVERWRITE); > + boot_fdt_reserve_region(addr, size, LMB_NOOVERWRITE, free); > } > > /* process reserved-memory */ > @@ -131,7 +151,8 @@ void boot_fdt_add_mem_rsv_regions(void *fdt_blob) > flags = LMB_NOMAP; > addr = res.start; > size = res.end - res.start + 1; > - boot_fdt_reserve_region(addr, size, flags); > + boot_fdt_reserve_region(addr, size, flags, > + free); > } > > subnode = fdt_next_subnode(fdt_blob, subnode); > diff --git a/include/image.h b/include/image.h > index 34efac6056d..68dfa4716ab 100644 > --- a/include/image.h > +++ b/include/image.h > @@ -827,7 +827,7 @@ int boot_get_fdt(void *buf, const char *select, uint arch, > struct bootm_headers *images, char **of_flat_tree, > ulong *of_size); > > -void boot_fdt_add_mem_rsv_regions(void *fdt_blob); > +void boot_fdt_add_mem_rsv_regions(void *fdt_blob, bool free); > int boot_relocate_fdt(char **of_flat_tree, ulong *of_size); > > int boot_ramdisk_high(ulong rd_data, ulong rd_len, ulong *initrd_start, > diff --git a/lib/lmb.c b/lib/lmb.c > index 8f12c6ad8e5..9a8c70b778a 100644 > --- a/lib/lmb.c > +++ b/lib/lmb.c > @@ -581,7 +581,7 @@ static void lmb_reserve_common(void *fdt_blob) > lmb_reserve_uboot_region(); > > if (CONFIG_IS_ENABLED(OF_LIBFDT) && fdt_blob) > - boot_fdt_add_mem_rsv_regions(fdt_blob); > + boot_fdt_add_mem_rsv_regions(fdt_blob, false); > } > > static __maybe_unused void lmb_reserve_common_spl(void) > -- > 2.53.0 > With the change above Acked-by: Ilias Apalodimas <[email protected]>
