Hi Sughosh,
On Thu, 4 Jul 2024 at 08:38, Sughosh Ganu <sughosh.g...@linaro.org> wrote:
>
> Mark the EFI runtime memory region as reserved memory during board
> init so that it does not get allocated by the LMB module on subsequent
> memory requests.
>
> Signed-off-by: Sughosh Ganu <sughosh.g...@linaro.org>
> ---
> Changes since V1: New patch
>
> lib/lmb.c | 41 ++++++++++++++++++++---------------------
> 1 file changed, 20 insertions(+), 21 deletions(-)
I see again that this is getting circular. Can you look at what is
actually allocated by EFI on init (i.e. before anything is booted)?
>
> diff --git a/lib/lmb.c b/lib/lmb.c
> index 387ec2ac65..6018f1de31 100644
> --- a/lib/lmb.c
> +++ b/lib/lmb.c
> @@ -19,6 +19,7 @@
> #include <asm/global_data.h>
> #include <asm/sections.h>
> #include <linux/kernel.h>
> +#include <linux/sizes.h>
>
> DECLARE_GLOBAL_DATA_PTR;
>
> @@ -212,33 +213,31 @@ void arch_lmb_reserve_generic(ulong sp, ulong end,
> ulong align)
> /**
> * efi_lmb_reserve() - add reservations for EFI memory
> *
> - * Add reservations for all EFI memory areas that are not
> - * EFI_CONVENTIONAL_MEMORY.
> + * Add reservations for EFI runtime services memory
> *
> - * Return: 0 on success, 1 on failure
> + * Return: None
> */
> -static __maybe_unused int efi_lmb_reserve(void)
> +static __maybe_unused void efi_lmb_reserve(void)
> {
> - struct efi_mem_desc *memmap = NULL, *map;
> - efi_uintn_t i, map_size = 0;
> - efi_status_t ret;
> + phys_addr_t runtime_start, runtime_end;
> + unsigned long runtime_mask = EFI_PAGE_MASK;
>
> - ret = efi_get_memory_map_alloc(&map_size, &memmap);
> - if (ret != EFI_SUCCESS)
> - return 1;
> +#if defined(__aarch64__)
> + /*
> + * Runtime Services must be 64KiB aligned according to the
> + * "AArch64 Platforms" section in the UEFI spec (2.7+).
> + */
>
> - for (i = 0, map = memmap; i < map_size / sizeof(*map); ++map, ++i) {
> - if (map->type != EFI_CONVENTIONAL_MEMORY) {
> - lmb_reserve_flags(map_to_sysmem((void *)(uintptr_t)
> - map->physical_start),
> - map->num_pages * EFI_PAGE_SIZE,
> - map->type ==
> EFI_RESERVED_MEMORY_TYPE
> - ? LMB_NOMAP : LMB_NONE);
> - }
> - }
> - efi_free_pool(memmap);
> + runtime_mask = SZ_64K - 1;
> +#endif
>
> - return 0;
> + /* Reserve the EFI runtime services memory */
> + runtime_start = (uintptr_t)__efi_runtime_start & ~runtime_mask;
> + runtime_end = (uintptr_t)__efi_runtime_stop;
> + runtime_end = (runtime_end + runtime_mask) & ~runtime_mask;
> +
> + lmb_reserve_flags(runtime_start, runtime_end - runtime_start,
> + LMB_NOOVERWRITE | LMB_NONOTIFY);
> }
>
> static void lmb_reserve_common(void *fdt_blob)
> --
> 2.34.1
>
Regards,
Simon
