dt-bindings: usb: mtk-xhci: Add binding for MediaTek xHCI host controller

[oweals/u-boot.git] / doc / README.gpt

diff --git a/doc/README.gpt b/doc/README.gpt
index a6f6de6a0f5f78549689f148844b708aac5b4b3e..facd7afc3acdb70560096d3cdc417a68b734ae3f 100644 (file)
--- a/doc/README.gpt
+++ b/doc/README.gpt
@@ -1,10 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0+

 #
 #  Copyright (C) 2012 Samsung Electronics
 #
 #  Lukasz Majewski <l.majewski@samsung.com>
 #
 #  Copyright (C) 2012 Samsung Electronics
 #
 #  Lukasz Majewski <l.majewski@samsung.com>

-#
-#
-# SPDX-License-Identifier:     GPL-2.0+

 
 Glossary:
 ========
 
 Glossary:
 ========


@@ -156,22 +154,23 @@ Creating GPT partitions in U-Boot:
 To restore GUID partition table one needs to:
 1. Define partition layout in the environment.
    Format of partitions layout:
 To restore GUID partition table one needs to:
 1. Define partition layout in the environment.
    Format of partitions layout:

-     "partitions=uuid_disk=...;name=u-boot,size=60MiB,uuid=...;
+     "uuid_disk=...;name=u-boot,size=60MiB,uuid=...;

        name=kernel,size=60MiB,uuid=...;"
      or
        name=kernel,size=60MiB,uuid=...;"
      or

-     "partitions=uuid_disk=${uuid_gpt_disk};name=${uboot_name},
+     "uuid_disk=${uuid_gpt_disk};name=${uboot_name},

        size=${uboot_size},uuid=${uboot_uuid};"
 
    The fields 'name' and 'size' are mandatory for every partition.
    The field 'start' is optional.
 
        size=${uboot_size},uuid=${uboot_uuid};"
 
    The fields 'name' and 'size' are mandatory for every partition.
    The field 'start' is optional.
 

-   If field 'size' of the last partition is 0, the partiton is extended
+   If field 'size' of the last partition is 0, the partition is extended

    up to the end of the device.
 
    The fields 'uuid' and 'uuid_disk' are optional if CONFIG_RANDOM_UUID is
    enabled. A random uuid will be used if omitted or they point to an empty/
    non-existent environment variable. The environment variable will be set to
    up to the end of the device.
 
    The fields 'uuid' and 'uuid_disk' are optional if CONFIG_RANDOM_UUID is
    enabled. A random uuid will be used if omitted or they point to an empty/
    non-existent environment variable. The environment variable will be set to

-   the generated UUID.
+   the generated UUID.  The 'gpt guid' command reads the current value of the
+   uuid_disk from the GPT.

 
    The field 'bootable' is optional, it is used to mark the GPT partition
    bootable (set attribute flags "Legacy BIOS bootable").
 
    The field 'bootable' is optional, it is used to mark the GPT partition
    bootable (set attribute flags "Legacy BIOS bootable").


@@ -209,6 +208,34 @@ Following line can be used to assess if GPT verification has succeed:
 U-BOOT> gpt verify mmc 0 $partitions
 U-BOOT> if test $? = 0; then echo "GPT OK"; else echo "GPT ERR"; fi
 
 U-BOOT> gpt verify mmc 0 $partitions
 U-BOOT> if test $? = 0; then echo "GPT OK"; else echo "GPT ERR"; fi
 

+Renaming GPT partitions from U-Boot:
+====================================
+
+GPT partition names are a mechanism via which userspace and U-Boot can
+communicate about software updates and boot failure.  The 'gpt guid',
+'gpt read', 'gpt rename' and 'gpt swap' commands facilitate
+programmatic renaming of partitions from bootscripts by generating and
+modifying the partitions layout string.  Here is an illustration of
+employing 'swap' to exchange 'primary' and 'backup' partition names:
+
+U-BOOT> gpt swap mmc 0 primary backup
+
+Afterwards, all partitions previously named 'primary' will be named
+'backup', and vice-versa.  Alternatively, single partitions may be
+renamed.  In this example, mmc0's first partition will be renamed
+'primary':
+
+U-BOOT> gpt rename mmc 0 1 primary
+
+The GPT functionality may be tested with the 'sandbox' board by
+creating a disk image as described under 'Block Device Emulation' in
+doc/arch/index.rst:
+
+=>host bind 0 ./disk.raw
+=> gpt read host 0
+[ . . . ]
+=> gpt swap host 0 name othername
+[ . . . ]

 
 Partition type GUID:
 ====================
 
 Partition type GUID:
 ====================


@@ -219,7 +246,7 @@ PARTITION_BASIC_DATA_GUID (EBD0A0A2-B9E5-4433-87C0-68B6B72699C7).
 If you define 'CONFIG_PARTITION_TYPE_GUID', a optionnal parameter 'type'
 can specify a other partition type guid:
 
 If you define 'CONFIG_PARTITION_TYPE_GUID', a optionnal parameter 'type'
 can specify a other partition type guid:
 

-     "partitions=uuid_disk=...;name=u-boot,size=60MiB,uuid=...;
+     "uuid_disk=...;name=u-boot,size=60MiB,uuid=...;

        name=kernel,size=60MiB,uuid=...,
        type=0FC63DAF-8483-4772-8E79-3D69D8477DE4;"
 
        name=kernel,size=60MiB,uuid=...,
        type=0FC63DAF-8483-4772-8E79-3D69D8477DE4;"
 


@@ -241,7 +268,7 @@ Some strings can be also used at the place of known GUID :
        "lvm"    = PARTITION_LINUX_LVM_GUID
                   (E6D6D379-F507-44C2-A23C-238F2A3DF928)
 
        "lvm"    = PARTITION_LINUX_LVM_GUID
                   (E6D6D379-F507-44C2-A23C-238F2A3DF928)
 

-    "partitions=uuid_disk=...;name=u-boot,size=60MiB,uuid=...;
+    "uuid_disk=...;name=u-boot,size=60MiB,uuid=...;

        name=kernel,size=60MiB,uuid=...,type=linux;"
 
 They are also used to display the type of partition in "part list" command.
        name=kernel,size=60MiB,uuid=...,type=linux;"
 
 They are also used to display the type of partition in "part list" command.