From: Stephen Warren swarren@nvidia.com
Some boards define a maximum usable RAM top that's more restrictive than the ranges defined by U-Boot's memory bank definitions[1]. In this case, the unusable RAM isn't mapped in the page tables, and so the EFI code must not attempt to allocate RAM from outside the usable regions. Fix efi_find_free_memory() to detect when max_addr is unconstrained or out of range, and substitue a valid value.
[1] For example, when some peripherals can't access RAM above 4GiB, it's simplest to force U-Boot's ram_top to a smaller value to avoid dealing with this issue more explicitly. However, the RAM bank definitions still describe the unusable RAM so that the booted OS has access to it, since the OS can typically deal with such restrictions in a more complex manner.
Fixes: aa909462d018 "efi_loader: efi_allocate_pages is too restrictive" Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: Alexander Graf agraf@suse.de Signed-off-by: Stephen Warren swarren@nvidia.com --- lib/efi_loader/efi_memory.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/lib/efi_loader/efi_memory.c b/lib/efi_loader/efi_memory.c index 967c3f733e4c..5064ff2ccbe8 100644 --- a/lib/efi_loader/efi_memory.c +++ b/lib/efi_loader/efi_memory.c @@ -251,6 +251,9 @@ static uint64_t efi_find_free_memory(uint64_t len, uint64_t max_addr) { struct list_head *lhandle;
+ if ((max_addr == -1ULL) || (max_addr > gd->ram_top)) + max_addr = gd->ram_top; + list_for_each(lhandle, &efi_mem) { struct efi_mem_list *lmem = list_entry(lhandle, struct efi_mem_list, link);