[PATCH v2 2/4] cmd: bootefi: Parse reserved-memory node from DT

[Heinrich Schuchardt]

On 3/14/20 1:55 AM, Atish Patra wrote:
> On Fri, Mar 13, 2020 at 5:12 PM Atish Patra <atish.patra at wdc.com> wrote:
>>
>> Currently, bootefi only parses memory reservation block to setup
>> EFI reserved memory mappings. However, it doesn't parse the
>> reserved-memory[1] device tree node that also can contain the
>> reserved memory regions.
>>
>> Add capability to parse reserved-memory node and update the EFI memory
>> mappings accordingly.

Hello Atish,

thanks for reporting the problem.

I would appreciate a test to verify that the code really works. We
should add both types of reserved-memory device tree node to the sandbox
device-tree and parse the output of 'efidebug memmap' and compare it to
the output of 'fdt print'. Could you, please, provide a first patch for
sandbox.dts and sandbox64.dts. The next step then would be to build a
Python test.

This patch series could be split into two. One for EFI and one for RISC-V.

(see comment below)

>>
>> 1. <U-Boot source>/doc/device-tree-bindings/reserved-memory/reserved-memory.txt]
>>
>> Signed-off-by: Atish Patra <atish.patra at wdc.com>
>> ---
>>   cmd/bootefi.c | 42 +++++++++++++++++++++++++++++++++---------
>>   1 file changed, 33 insertions(+), 9 deletions(-)
>>
>> diff --git a/cmd/bootefi.c b/cmd/bootefi.c
>> index 24fc42ae898e..43b36fbacfcd 100644
>> --- a/cmd/bootefi.c
>> +++ b/cmd/bootefi.c
>> @@ -149,6 +149,20 @@ done:
>>          return ret;
>>   }
>>
>> +static void efi_reserve_memory(uint64_t addr, uint64_t size)
>> +{
>> +       uint64_t pages;
>> +
>> +       /* Convert from sandbox address space. */
>> +       addr = (uintptr_t)map_sysmem(addr, 0);
>> +       pages = efi_size_in_pages(size + (addr & EFI_PAGE_MASK));
>> +       addr &= ~EFI_PAGE_MASK;
>> +       if (efi_add_memory_map(addr, pages, EFI_RESERVED_MEMORY_TYPE,
>> +                              false) != EFI_SUCCESS)
>> +               printf("Reserved memory mapping failed addr %llx size %llx\n",
>> +                     (unsigned long long)addr, (unsigned long long)size);
>> +}
>> +
>>   /**
>>    * efi_carve_out_dt_rsv() - Carve out DT reserved memory ranges
>>    *
>> @@ -161,7 +175,8 @@ done:
>>   static void efi_carve_out_dt_rsv(void *fdt)
>>   {
>>          int nr_rsv, i;
>> -       uint64_t addr, size, pages;
>> +       uint64_t addr, size;
>> +       int nodeoffset, subnode;
>>
>>          nr_rsv = fdt_num_mem_rsv(fdt);
>>
>> @@ -169,15 +184,24 @@ static void efi_carve_out_dt_rsv(void *fdt)
>>          for (i = 0; i < nr_rsv; i++) {
>>                  if (fdt_get_mem_rsv(fdt, i, &addr, &size) != 0)
>>                          continue;
>> +               efi_reserve_memory(addr, size);
>> +       }
>>
>> -               /* Convert from sandbox address space. */
>> -               addr = (uintptr_t)map_sysmem(addr, 0);
>> -
>> -               pages = efi_size_in_pages(size + (addr & EFI_PAGE_MASK));
>> -               addr &= ~EFI_PAGE_MASK;
>> -               if (efi_add_memory_map(addr, pages, EFI_RESERVED_MEMORY_TYPE,
>> -                                      false) != EFI_SUCCESS)
>> -                       printf("FDT memrsv map %d: Failed to add to map\n", i);
>> +       /* process reserved-memory */
>> +       nodeoffset = fdt_subnode_offset(fdt, 0, "reserved-memory");
>> +       if (nodeoffset >= 0) {
>> +               subnode = fdt_first_subnode(fdt, nodeoffset);
>> +               while (subnode >= 0) {
>> +                       /* check if this subnode has a reg property */
>> +                       addr = fdtdec_get_addr_size(fdt, subnode, "reg",
>> +                                                   (fdt_size_t *)&size);
>> +                       if (addr == FDT_ADDR_T_NONE) {
>> +                               debug("failed to read address/size\n");

Linux
Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt has:

"Each child of the reserved-memory node specifies one or more regions of
reserved memory. Each child node may either use a 'reg' property to
specify a specific range of reserved memory, or a 'size' property with
optional constraints to request a dynamically allocated block of memory.
... If both reg and size are present, then the reg property takes
precedence and size is ignored."

So finding no reg property should not be considered a bug. I see no need
for a debug statement here.

For the sandbox test we should have a node with 'size' and at least two
nodes with 'reg'.

Otherwise:

Reviewed-by: Heinrich Schuchardt <xypron.glpk at gmx.de>

>> +                               continue;
>> +                       }
>> +                       efi_reserve_memory(addr, size);
>> +                       subnode = fdt_next_subnode(fdt, subnode);
>> +               }
>>          }
>>   }
>>
>> --
>> 2.25.1
>>
>
> Fixed palmer's email address. Sorry for the spam.
>