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+.. SPDX-License-Identifier: GPL-2.0+
+.. Copyright 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
+
+efi command
+===========
+
+Synopsis
+--------
+
+::
+
+    efi mem [all]
+
+Description
+-----------
+
+The *efi* command provides information about the EFI environment U-Boot is
+running in, when it is started from EFI.
+
+When running as an EFI app, this command queries EFI boot services for the
+information. When running as an EFI payload, EFI boot services have been
+stopped, so it uses the information collected by the boot stub before that
+happened.
+
+efi mem
+~~~~~~~
+
+This shows the EFI memory map, sorted in order of physical address.
+
+This is normally a very large table. To help reduce the amount of detritus,
+boot-time memory is normally merged with conventional memory. Use the 'all'
+argument to show everything.
+
+The fields are as follows:
+
+#
+    Entry number (sequentially from 0)
+
+Type
+    Memory type. EFI has a large number of memory types. The type is shown in
+    the format <n>:<name> where in is the format number in hex and <name> is the
+    name.
+
+Physical
+    Physical address
+
+Virtual
+    Virtual address
+
+Size
+    Size of memory area in bytes
+
+Attributes
+    Shows a code for memory attributes. The key for this is shown below the
+    table.
+
+Example
+-------
+
+::
+
+    => efi mem
+    EFI table at 0, memory map 000000001ad38b60, size 1260, key a79, version 1, descr. size 0x30
+     #  Type              Physical     Virtual        Size  Attributes
+     0  7:conv          0000000000  0000000000  00000a0000  f
+        <gap>           00000a0000              0000060000
+     1  7:conv          0000100000  0000000000  0000700000  f
+     2  a:acpi_nvs      0000800000  0000000000  0000008000  f
+     3  7:conv          0000808000  0000000000  0000008000  f
+     4  a:acpi_nvs      0000810000  0000000000  00000f0000  f
+     5  7:conv          0000900000  0000000000  001efef000  f
+     6  6:rt_data       001f8ef000  0000000000  0000100000  rf
+     7  5:rt_code       001f9ef000  0000000000  0000100000  rf
+     8  0:reserved      001faef000  0000000000  0000080000  f
+     9  9:acpi_reclaim  001fb6f000  0000000000  0000010000  f
+    10  a:acpi_nvs      001fb7f000  0000000000  0000080000  f
+    11  7:conv          001fbff000  0000000000  0000359000  f
+    12  6:rt_data       001ff58000  0000000000  0000020000  rf
+    13  a:acpi_nvs      001ff78000  0000000000  0000088000  f
+        <gap>           0020000000              0090000000
+    14  0:reserved      00b0000000  0000000000  0010000000  1
+
+    Attributes key:
+     f: uncached, write-coalescing, write-through, write-back
+    rf: uncached, write-coalescing, write-through, write-back, needs runtime mapping
+     1: uncached
+    *Some areas are merged (use 'all' to see)
+
+
+    => efi mem  all
+    EFI table at 0, memory map 000000001ad38bb0, size 1260, key a79, version 1, descr. size 0x30
+     #  Type              Physical     Virtual        Size  Attributes
+     0  3:bs_code       0000000000  0000000000  0000001000  f
+     1  7:conv          0000001000  0000000000  000009f000  f
+        <gap>           00000a0000              0000060000
+     2  7:conv          0000100000  0000000000  0000700000  f
+     3  a:acpi_nvs      0000800000  0000000000  0000008000  f
+     4  7:conv          0000808000  0000000000  0000008000  f
+     5  a:acpi_nvs      0000810000  0000000000  00000f0000  f
+     6  4:bs_data       0000900000  0000000000  0000c00000  f
+     7  7:conv          0001500000  0000000000  000aa36000  f
+     8  2:loader_data   000bf36000  0000000000  0010000000  f
+     9  4:bs_data       001bf36000  0000000000  0000020000  f
+    10  7:conv          001bf56000  0000000000  00021e1000  f
+    11  1:loader_code   001e137000  0000000000  00000c4000  f
+    12  7:conv          001e1fb000  0000000000  000009b000  f
+    13  1:loader_code   001e296000  0000000000  00000e2000  f
+    14  7:conv          001e378000  0000000000  000005b000  f
+    15  4:bs_data       001e3d3000  0000000000  000001e000  f
+    16  7:conv          001e3f1000  0000000000  0000016000  f
+    17  4:bs_data       001e407000  0000000000  0000016000  f
+    18  2:loader_data   001e41d000  0000000000  0000002000  f
+    19  4:bs_data       001e41f000  0000000000  0000828000  f
+    20  3:bs_code       001ec47000  0000000000  0000045000  f
+    21  4:bs_data       001ec8c000  0000000000  0000001000  f
+    22  3:bs_code       001ec8d000  0000000000  000000e000  f
+    23  4:bs_data       001ec9b000  0000000000  0000001000  f
+    24  3:bs_code       001ec9c000  0000000000  000002c000  f
+    25  4:bs_data       001ecc8000  0000000000  0000001000  f
+    26  3:bs_code       001ecc9000  0000000000  000000c000  f
+    27  4:bs_data       001ecd5000  0000000000  0000006000  f
+    28  3:bs_code       001ecdb000  0000000000  0000014000  f
+    29  4:bs_data       001ecef000  0000000000  0000001000  f
+    30  3:bs_code       001ecf0000  0000000000  000005b000  f
+    31  4:bs_data       001ed4b000  0000000000  000000b000  f
+    32  3:bs_code       001ed56000  0000000000  0000024000  f
+    33  4:bs_data       001ed7a000  0000000000  0000006000  f
+    34  3:bs_code       001ed80000  0000000000  0000010000  f
+    35  4:bs_data       001ed90000  0000000000  0000002000  f
+    36  3:bs_code       001ed92000  0000000000  0000025000  f
+    37  4:bs_data       001edb7000  0000000000  0000003000  f
+    38  3:bs_code       001edba000  0000000000  0000011000  f
+    39  4:bs_data       001edcb000  0000000000  0000008000  f
+    40  3:bs_code       001edd3000  0000000000  000002d000  f
+    41  4:bs_data       001ee00000  0000000000  0000201000  f
+    42  3:bs_code       001f001000  0000000000  0000024000  f
+    43  4:bs_data       001f025000  0000000000  0000002000  f
+    44  3:bs_code       001f027000  0000000000  0000009000  f
+    45  4:bs_data       001f030000  0000000000  0000005000  f
+    46  3:bs_code       001f035000  0000000000  000002f000  f
+    47  4:bs_data       001f064000  0000000000  0000001000  f
+    48  3:bs_code       001f065000  0000000000  0000005000  f
+    49  4:bs_data       001f06a000  0000000000  0000005000  f
+    50  3:bs_code       001f06f000  0000000000  0000007000  f
+    51  4:bs_data       001f076000  0000000000  0000007000  f
+    52  3:bs_code       001f07d000  0000000000  000000d000  f
+    53  4:bs_data       001f08a000  0000000000  0000001000  f
+    54  3:bs_code       001f08b000  0000000000  0000006000  f
+    55  4:bs_data       001f091000  0000000000  0000004000  f
+    56  3:bs_code       001f095000  0000000000  000000d000  f
+    57  4:bs_data       001f0a2000  0000000000  0000003000  f
+    58  3:bs_code       001f0a5000  0000000000  0000026000  f
+    59  4:bs_data       001f0cb000  0000000000  0000005000  f
+    60  3:bs_code       001f0d0000  0000000000  0000019000  f
+    61  4:bs_data       001f0e9000  0000000000  0000004000  f
+    62  3:bs_code       001f0ed000  0000000000  0000024000  f
+    63  4:bs_data       001f111000  0000000000  0000008000  f
+    64  3:bs_code       001f119000  0000000000  000000b000  f
+    65  4:bs_data       001f124000  0000000000  0000001000  f
+    66  3:bs_code       001f125000  0000000000  0000002000  f
+    67  4:bs_data       001f127000  0000000000  0000002000  f
+    68  3:bs_code       001f129000  0000000000  0000009000  f
+    69  4:bs_data       001f132000  0000000000  0000003000  f
+    70  3:bs_code       001f135000  0000000000  0000005000  f
+    71  4:bs_data       001f13a000  0000000000  0000003000  f
+    72  3:bs_code       001f13d000  0000000000  0000005000  f
+    73  4:bs_data       001f142000  0000000000  0000003000  f
+    74  3:bs_code       001f145000  0000000000  0000011000  f
+    75  4:bs_data       001f156000  0000000000  000000b000  f
+    76  3:bs_code       001f161000  0000000000  0000009000  f
+    77  4:bs_data       001f16a000  0000000000  0000400000  f
+    78  3:bs_code       001f56a000  0000000000  0000006000  f
+    79  4:bs_data       001f570000  0000000000  0000001000  f
+    80  3:bs_code       001f571000  0000000000  0000001000  f
+    81  4:bs_data       001f572000  0000000000  0000002000  f
+    82  3:bs_code       001f574000  0000000000  0000017000  f
+    83  4:bs_data       001f58b000  0000000000  0000364000  f
+    84  6:rt_data       001f8ef000  0000000000  0000100000  rf
+    85  5:rt_code       001f9ef000  0000000000  0000100000  rf
+    86  0:reserved      001faef000  0000000000  0000080000  f
+    87  9:acpi_reclaim  001fb6f000  0000000000  0000010000  f
+    88  a:acpi_nvs      001fb7f000  0000000000  0000080000  f
+    89  4:bs_data       001fbff000  0000000000  0000201000  f
+    90  7:conv          001fe00000  0000000000  00000e8000  f
+    91  4:bs_data       001fee8000  0000000000  0000020000  f
+    92  3:bs_code       001ff08000  0000000000  0000026000  f
+    93  4:bs_data       001ff2e000  0000000000  0000009000  f
+    94  3:bs_code       001ff37000  0000000000  0000021000  f
+    95  6:rt_data       001ff58000  0000000000  0000020000  rf
+    96  a:acpi_nvs      001ff78000  0000000000  0000088000  f
+        <gap>           0020000000              0090000000
+    97  0:reserved      00b0000000  0000000000  0010000000  1
+
+    Attributes key:
+     f: uncached, write-coalescing, write-through, write-back
+    rf: uncached, write-coalescing, write-through, write-back, needs runtime mapping
+     1: uncached