mx6sabresd
mx6ul_14x14_evk
mx6ullevk
+ psb
--- /dev/null
+i.MX7D/i.MX8MM SRC_GPR10 PERSIST_SECONDARY_BOOT for bootloader A/B switching
+============================================================================
+
+Introduction
+------------
+Since at least iMX53 until iMX8MM, it is possible to have two copies of
+bootloader in SD/eMMC and switch between them. The switch is triggered
+either by the BootROM in case the bootloader image is faulty OR can be
+enforced by the user.
+
+Operation
+---------
+ #. Upon Power-On Reset (POR)
+
+ - SRC_GPR10 bit PERSIST_SECONDARY_BOOT is set to 0
+ - BootROM attempts to start bootloader A-copy
+
+ - if A-copy valid
+
+ - BootROM starts A-copy
+ - END
+
+ - if A-copy NOT valid
+
+ - BootROM sets SRC_GPR10 bit PERSIST_SECONDARY_BOOT to 1
+ - BootROM triggers WARM reset, GOTO 1)
+ - END
+
+ #. Upon COLD Reset
+
+ - GOTO 1)
+ - END
+
+ #. Upon WARM Reset
+
+ - SRC_GPR10 bit PERSIST_SECONDARY_BOOT is retained
+
+ - if SRC_GPR10 bit PERSIST_SECONDARY_BOOT is 0
+
+ - BootROM attempts to start bootloader A-copy
+
+ - if A-copy valid
+
+ - BootROM starts A-copy
+ - END
+
+ - if A-copy NOT valid
+
+ - BootROM sets SRC_GPR10 bit PERSIST_SECONDARY_BOOT to 1
+ - BootROM triggers WARM reset. GOTO 1.3)
+ - END
+
+ - if SRC_GPR10 bit PERSIST_SECONDARY_BOOT is 1
+
+ - BootROM attempts to start bootloader B-copy
+
+ - if B-copy valid
+
+ - BootROM starts B-copy
+ - END
+
+ - if B-copy NOT valid
+ - System hangs
+ - END
+
+Setup
+-----
+The bootloader A-copy must be placed at predetermined offset in SD/eMMC. The
+bootloader B-copy area offset is determined by an offset stored in Secondary
+Image Table (SIT). The SIT must be placed at predetermined offset in SD/eMMC.
+
+The following table contains offset of SIT, bootloader A-copy and recommended
+bootloader B-copy offset. The offsets are in 512 Byte sector units (that is
+offset 0x1 means 512 Bytes from the start of SD/eMMC card data partition).
+For details on the addition of two numbers in recommended B-copy offset, see
+SIT format below.
+
++----------+--------------------+-----------------------+-----------------------------+
+| SoC | SIT offset (fixed) | A-copy offset (fixed) | B-copy offset (recommended) |
++----------+--------------------+-----------------------+-----------------------------+
+| iMX7D | 0x1 | 0x2 | 0x800+0x2 |
++----------+--------------------+-----------------------+-----------------------------+
+| iMX8MM | 0x41 | 0x42 | 0x1000+0x42 |
++----------+--------------------+-----------------------+-----------------------------+
+
+SIT format
+~~~~~~~~~~
+SIT is a 20 byte long structure containing of 5 32-bit words. Those encode
+bootloader B-copy area offset (called "firstSectorNumber"), magic value
+(called "tag") that is always 0x00112233, and three unused words set to 0.
+SIT is documented in [1]_ and [2]_. Example SIT are below::
+
+ $ hexdump -vC sit-mx7d.bin
+ 00000000 00 00 00 00
+ 00000004 00 00 00 00
+ 00000008 33 22 11 00 <--- This is the "tag"
+ 0000000c 00 08 00 00 <--- This is the "firstSectorNumber"
+ 00000010 00 00 00 00
+
+ $ hexdump -vC sit-mx8mm.bin
+ 00000000 00 00 00 00
+ 00000004 00 00 00 00
+ 00000008 33 22 11 00 <--- This is the "tag"
+ 0000000c 00 10 00 00 <--- This is the "firstSectorNumber"
+ 00000010 00 00 00 00
+
+B-copy area offset ("firstSectorNumber") is offset, in units of 512 Byte
+sectors, that is added to the start of boot media when switching between
+A-copy and B-copy. For A-copy, this offset is 0x0. For B-copy, this offset
+is determined by SIT (e.g. if firstSectorNumber is 0x1000 as it is above
+in sit-mx8mm.bin, then the B-copy offset is 0x1000 sectors = 2 MiB).
+
+Bootloader A-copy (e.g. u-boot.imx or flash.bin) is placed at fixed offset
+from A-copy area offset (e.g. 0x2 sectors from sector 0x0 for iMX7D, which
+means u-boot.imx A-copy must be written to sector 0x2).
+
+The same applies to bootloader B-copy, which is placed at fixed offset from
+B-copy area offset determined by SIT (e.g. 0x2 sectors from sector 0x800 [see
+sit-mx7d.bin example above, this can be changed in SIT firstSectorNumber] for
+iMX7D, which means u-boot.imx B-copy must be written to sector 0x802)
+
+**WARNING:**
+B-copy area offset ("firstSectorNumber") is NOT equal to bootloader
+(image, which is u-boot.imx or flash.bin) B-copy offset.
+
+To generate SIT, use for example the following bourne shell printf command::
+
+$ printf '\x0\x0\x0\x0\x0\x0\x0\x0\x33\x22\x11\x00\x00\x08\x00\x00\x0\x0\x0\x0' > sit-mx7d.bin
+$ printf '\x0\x0\x0\x0\x0\x0\x0\x0\x33\x22\x11\x00\x00\x10\x00\x00\x0\x0\x0\x0' > sit-mx8mm.bin
+
+Write bootloader A/B copy and SIT to SD/eMMC
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Examples of writing SIT and two copies of bootloader to SD or eMMC:
+
+- iMX8MM, SD card at /dev/sdX, Linux command line
+ ::
+
+ $ dd if=sit-mx8mm.bin of=/dev/sdX bs=512 seek=65
+ $ dd if=flash.bin of=/dev/sdX bs=512 seek=66
+ $ dd if=flash.bin of=/dev/sdX bs=512 seek=4162
+
+- iMX8MM, eMMC 1 data partition, U-Boot command line
+ ::
+
+ => mmc partconf 1 0 0 0
+
+ => dhcp ${loadaddr} sit-mx8mm.bin
+ => mmc dev 1
+ => mmc write ${loadaddr} 0x41 0x1
+
+ => dhcp ${loadaddr} flash.bin
+ => setexpr blkcnt ${filesize} + 0x1ff && setexpr blkcnt ${blkcnt} / 0x200
+ => mmc dev 1
+ => mmc write ${loadaddr} 0x42 ${blkcnt}
+ => mmc write ${loadaddr} 0x1042 ${blkcnt}
+
+WARM reset into B-copy using WDT
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+To perform a reboot into B-copy, the PERSIST_SECONDARY_BOOT must be set
+in SRC_GPR0 register. Example on iMX8MM::
+
+ => mw 0x30390098 0x40000000
+
+A WARM reset can be triggered using WDT as follows::
+
+ => mw.w 0x30280000 0x25
+
+References
+----------
+
+.. [1] i.MX 7Dual Applications Processor Reference Manual, Rev. 1, 01/2018 ; section 6.6.5.3.5 Redundant boot support for expansion device
+.. [2] i.MX 8M Mini Applications Processor Reference Manual, Rev. 3, 11/2020 ; section 6.1.5.4.5 Redundant boot support for expansion device
+++ /dev/null
-.. SPDX-License-Identifier: GPL-2.0+
-
-NXP i.MX Machine-specific doc
-=============================
-
-.. toctree::
- :maxdepth: 2
-
- misc/index
+++ /dev/null
-.. SPDX-License-Identifier: GPL-2.0+
-
-Miscellaneous
-=============
-
-.. toctree::
- :maxdepth: 2
-
- psb
+++ /dev/null
-i.MX7D/i.MX8MM SRC_GPR10 PERSIST_SECONDARY_BOOT for bootloader A/B switching
-============================================================================
-
-Introduction
-------------
-Since at least iMX53 until iMX8MM, it is possible to have two copies of
-bootloader in SD/eMMC and switch between them. The switch is triggered
-either by the BootROM in case the bootloader image is faulty OR can be
-enforced by the user.
-
-Operation
----------
- #. Upon Power-On Reset (POR)
-
- - SRC_GPR10 bit PERSIST_SECONDARY_BOOT is set to 0
- - BootROM attempts to start bootloader A-copy
-
- - if A-copy valid
-
- - BootROM starts A-copy
- - END
-
- - if A-copy NOT valid
-
- - BootROM sets SRC_GPR10 bit PERSIST_SECONDARY_BOOT to 1
- - BootROM triggers WARM reset, GOTO 1)
- - END
-
- #. Upon COLD Reset
-
- - GOTO 1)
- - END
-
- #. Upon WARM Reset
-
- - SRC_GPR10 bit PERSIST_SECONDARY_BOOT is retained
-
- - if SRC_GPR10 bit PERSIST_SECONDARY_BOOT is 0
-
- - BootROM attempts to start bootloader A-copy
-
- - if A-copy valid
-
- - BootROM starts A-copy
- - END
-
- - if A-copy NOT valid
-
- - BootROM sets SRC_GPR10 bit PERSIST_SECONDARY_BOOT to 1
- - BootROM triggers WARM reset. GOTO 1.3)
- - END
-
- - if SRC_GPR10 bit PERSIST_SECONDARY_BOOT is 1
-
- - BootROM attempts to start bootloader B-copy
-
- - if B-copy valid
-
- - BootROM starts B-copy
- - END
-
- - if B-copy NOT valid
- - System hangs
- - END
-
-Setup
------
-The bootloader A-copy must be placed at predetermined offset in SD/eMMC. The
-bootloader B-copy area offset is determined by an offset stored in Secondary
-Image Table (SIT). The SIT must be placed at predetermined offset in SD/eMMC.
-
-The following table contains offset of SIT, bootloader A-copy and recommended
-bootloader B-copy offset. The offsets are in 512 Byte sector units (that is
-offset 0x1 means 512 Bytes from the start of SD/eMMC card data partition).
-For details on the addition of two numbers in recommended B-copy offset, see
-SIT format below.
-
-+----------+--------------------+-----------------------+-----------------------------+
-| SoC | SIT offset (fixed) | A-copy offset (fixed) | B-copy offset (recommended) |
-+----------+--------------------+-----------------------+-----------------------------+
-| iMX7D | 0x1 | 0x2 | 0x800+0x2 |
-+----------+--------------------+-----------------------+-----------------------------+
-| iMX8MM | 0x41 | 0x42 | 0x1000+0x42 |
-+----------+--------------------+-----------------------+-----------------------------+
-
-SIT format
-~~~~~~~~~~
-SIT is a 20 byte long structure containing of 5 32-bit words. Those encode
-bootloader B-copy area offset (called "firstSectorNumber"), magic value
-(called "tag") that is always 0x00112233, and three unused words set to 0.
-SIT is documented in [1]_ and [2]_. Example SIT are below::
-
- $ hexdump -vC sit-mx7d.bin
- 00000000 00 00 00 00
- 00000004 00 00 00 00
- 00000008 33 22 11 00 <--- This is the "tag"
- 0000000c 00 08 00 00 <--- This is the "firstSectorNumber"
- 00000010 00 00 00 00
-
- $ hexdump -vC sit-mx8mm.bin
- 00000000 00 00 00 00
- 00000004 00 00 00 00
- 00000008 33 22 11 00 <--- This is the "tag"
- 0000000c 00 10 00 00 <--- This is the "firstSectorNumber"
- 00000010 00 00 00 00
-
-B-copy area offset ("firstSectorNumber") is offset, in units of 512 Byte
-sectors, that is added to the start of boot media when switching between
-A-copy and B-copy. For A-copy, this offset is 0x0. For B-copy, this offset
-is determined by SIT (e.g. if firstSectorNumber is 0x1000 as it is above
-in sit-mx8mm.bin, then the B-copy offset is 0x1000 sectors = 2 MiB).
-
-Bootloader A-copy (e.g. u-boot.imx or flash.bin) is placed at fixed offset
-from A-copy area offset (e.g. 0x2 sectors from sector 0x0 for iMX7D, which
-means u-boot.imx A-copy must be written to sector 0x2).
-
-The same applies to bootloader B-copy, which is placed at fixed offset from
-B-copy area offset determined by SIT (e.g. 0x2 sectors from sector 0x800 [see
-sit-mx7d.bin example above, this can be changed in SIT firstSectorNumber] for
-iMX7D, which means u-boot.imx B-copy must be written to sector 0x802)
-
-**WARNING:**
-B-copy area offset ("firstSectorNumber") is NOT equal to bootloader
-(image, which is u-boot.imx or flash.bin) B-copy offset.
-
-To generate SIT, use for example the following bourne shell printf command::
-
-$ printf '\x0\x0\x0\x0\x0\x0\x0\x0\x33\x22\x11\x00\x00\x08\x00\x00\x0\x0\x0\x0' > sit-mx7d.bin
-$ printf '\x0\x0\x0\x0\x0\x0\x0\x0\x33\x22\x11\x00\x00\x10\x00\x00\x0\x0\x0\x0' > sit-mx8mm.bin
-
-Write bootloader A/B copy and SIT to SD/eMMC
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Examples of writing SIT and two copies of bootloader to SD or eMMC:
-
-- iMX8MM, SD card at /dev/sdX, Linux command line
- ::
-
- $ dd if=sit-mx8mm.bin of=/dev/sdX bs=512 seek=65
- $ dd if=flash.bin of=/dev/sdX bs=512 seek=66
- $ dd if=flash.bin of=/dev/sdX bs=512 seek=4162
-
-- iMX8MM, eMMC 1 data partition, U-Boot command line
- ::
-
- => mmc partconf 1 0 0 0
-
- => dhcp ${loadaddr} sit-mx8mm.bin
- => mmc dev 1
- => mmc write ${loadaddr} 0x41 0x1
-
- => dhcp ${loadaddr} flash.bin
- => setexpr blkcnt ${filesize} + 0x1ff && setexpr blkcnt ${blkcnt} / 0x200
- => mmc dev 1
- => mmc write ${loadaddr} 0x42 ${blkcnt}
- => mmc write ${loadaddr} 0x1042 ${blkcnt}
-
-WARM reset into B-copy using WDT
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-To perform a reboot into B-copy, the PERSIST_SECONDARY_BOOT must be set
-in SRC_GPR0 register. Example on iMX8MM::
-
- => mw 0x30390098 0x40000000
-
-A WARM reset can be triggered using WDT as follows::
-
- => mw.w 0x30280000 0x25
-
-References
-----------
-
-.. [1] i.MX 7Dual Applications Processor Reference Manual, Rev. 1, 01/2018 ; section 6.6.5.3.5 Redundant boot support for expansion device
-.. [2] i.MX 8M Mini Applications Processor Reference Manual, Rev. 3, 11/2020 ; section 6.1.5.4.5 Redundant boot support for expansion device
arch/index
-Machine-specific doc
---------------------
-
-These books provide programming details about machine-specific
-implementation.
-
-.. toctree::
- :maxdepth: 2
-
- imx/index
-
Board-specific doc
------------------
projects / J-u-boot.git / commitdiff