€•ñÁ      Œsphinx.addnodes”Œdocument”“”)”}”(Œ	rawsource”Œ ”Œchildren”]”(Œtranslations”ŒLanguagesNode”“”)”}”(hhh]”(h Œpending_xref”“”)”}”(hhh]”Œdocutils.nodes”ŒText”“”ŒChinese (Simplified)”…””}”Œparent”hsbaŒ
attributes”}”(Œids”]”Œclasses”]”Œnames”]”Œdupnames”]”Œbackrefs”]”Œ	refdomain”Œstd”Œreftype”Œdoc”Œ	reftarget”Œ*/translations/zh_CN/driver-api/mtd/spi-nor”Œmodname”NŒ	classname”NŒrefexplicit”ˆuŒtagname”hhhubh)”}”(hhh]”hŒChinese (Traditional)”…””}”hh2sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ*/translations/zh_TW/driver-api/mtd/spi-nor”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒItalian”…””}”hhFsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ*/translations/it_IT/driver-api/mtd/spi-nor”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒJapanese”…””}”hhZsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ*/translations/ja_JP/driver-api/mtd/spi-nor”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒKorean”…””}”hhnsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ*/translations/ko_KR/driver-api/mtd/spi-nor”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒPortuguese (Brazilian)”…””}”hh‚sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ*/translations/pt_BR/driver-api/mtd/spi-nor”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒSpanish”…””}”hh–sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ*/translations/sp_SP/driver-api/mtd/spi-nor”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubeh}”(h]”h ]”h"]”h$]”h&]”Œcurrent_language”ŒEnglish”uh1h
hhŒ	_document”hŒsource”NŒline”NubhŒsection”“”)”}”(hhh]”(hŒtitle”“”)”}”(hŒSPI NOR framework”h]”hŒSPI NOR framework”…””}”(hh¼h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhh·h²hh³ŒD/var/lib/git/docbuild/linux/Documentation/driver-api/mtd/spi-nor.rst”h´Kubh¶)”}”(hhh]”(h»)”}”(hŒ#How to propose a new flash addition”h]”hŒ#How to propose a new flash addition”…””}”(hhÎh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhhËh²hh³hÊh´KubhŒ	paragraph”“”)”}”(hŒðMost SPI NOR flashes comply with the JEDEC JESD216
Serial Flash Discoverable Parameter (SFDP) standard. SFDP describes
the functional and feature capabilities of serial flash devices in a
standard set of internal read-only parameter tables.”h]”hŒðMost SPI NOR flashes comply with the JEDEC JESD216
Serial Flash Discoverable Parameter (SFDP) standard. SFDP describes
the functional and feature capabilities of serial flash devices in a
standard set of internal read-only parameter tables.”…””}”(hhÞh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´KhhËh²hubhÝ)”}”(hXv  The SPI NOR driver queries the SFDP tables in order to determine the
flash's parameters and settings. If the flash defines the SFDP tables
it's likely that you won't need a flash entry at all, and instead
rely on the generic flash driver which probes the flash solely based
on its SFDP data. All one has to do is to specify the "jedec,spi-nor"
compatible in the device tree.”h]”hX€  The SPI NOR driver queries the SFDP tables in order to determine the
flashâ€™s parameters and settings. If the flash defines the SFDP tables
itâ€™s likely that you wonâ€™t need a flash entry at all, and instead
rely on the generic flash driver which probes the flash solely based
on its SFDP data. All one has to do is to specify the â€œjedec,spi-norâ€
compatible in the device tree.”…””}”(hhìh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´KhhËh²hubhÝ)”}”(hXv  There are cases however where you need to define an explicit flash
entry. This typically happens when the flash has settings or support
that is not covered by the SFDP tables (e.g. Block Protection), or
when the flash contains mangled SFDP data. If the later, one needs
to implement the ``spi_nor_fixups`` hooks in order to amend the SFDP
parameters with the correct values.”h]”(hX  There are cases however where you need to define an explicit flash
entry. This typically happens when the flash has settings or support
that is not covered by the SFDP tables (e.g. Block Protection), or
when the flash contains mangled SFDP data. If the later, one needs
to implement the ”…””}”(hhúh²hh³Nh´NubhŒliteral”“”)”}”(hŒ``spi_nor_fixups``”h]”hŒspi_nor_fixups”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j  hhúubhŒE hooks in order to amend the SFDP
parameters with the correct values.”…””}”(hhúh²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´KhhËh²hubeh}”(h]”Œ#how-to-propose-a-new-flash-addition”ah ]”h"]”Œ#how to propose a new flash addition”ah$]”h&]”uh1hµhh·h²hh³hÊh´Kubh¶)”}”(hhh]”(h»)”}”(hŒMinimum testing requirements”h]”hŒMinimum testing requirements”…””}”(hj'  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhj$  h²hh³hÊh´KubhÝ)”}”(hŒfDo all the tests from below and paste them in the commit's comments
section, after the ``---`` marker.”h]”(hŒYDo all the tests from below and paste them in the commitâ€™s comments
section, after the ”…””}”(hj5  h²hh³Nh´Nubj  )”}”(hŒ``---``”h]”hŒ---”…””}”(hj=  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j  hj5  ubhŒ marker.”…””}”(hj5  h²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´Khj$  h²hubhŒenumerated_list”“”)”}”(hhh]”(hŒ	list_item”“”)”}”(hŒîSpecify the controller that you used to test the flash and specify
the frequency at which the flash was operated, e.g.::

 This flash is populated on the X board and was tested at Y
 frequency using the Z (put compatible) SPI controller.
”h]”(hÝ)”}”(hŒxSpecify the controller that you used to test the flash and specify
the frequency at which the flash was operated, e.g.::”h]”hŒwSpecify the controller that you used to test the flash and specify
the frequency at which the flash was operated, e.g.:”…””}”(hj`  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´K!hj\  ubhŒliteral_block”“”)”}”(hŒqThis flash is populated on the X board and was tested at Y
frequency using the Z (put compatible) SPI controller.”h]”hŒqThis flash is populated on the X board and was tested at Y
frequency using the Z (put compatible) SPI controller.”…””}”hjp  sbah}”(h]”h ]”h"]”h$]”h&]”Œ	xml:space”Œpreserve”uh1jn  h³hÊh´K$hj\  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jZ  hjW  h²hh³hÊh´Nubj[  )”}”(hXÀ  Dump the sysfs entries and print the md5/sha1/sha256 SFDP checksum::

 root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/partname
 sst26vf064b
 root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/jedec_id
 bf2643
 root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/manufacturer
 sst
 root@1:~# xxd -p /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
 53464450060102ff00060110300000ff81000106000100ffbf0001180002
 0001fffffffffffffffffffffffffffffffffd20f1ffffffff0344eb086b
 083b80bbfeffffffffff00ffffff440b0c200dd80fd810d820914824806f
 1d81ed0f773830b030b0f7ffffff29c25cfff030c080ffffffffffffffff
 ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 ffffffffffffffffffffffffffffffffff0004fff37f0000f57f0000f9ff
 7d00f57f0000f37f0000ffffffffffffffffffffffffffffffffffffffff
 ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 ffffbf2643ffb95ffdff30f260f332ff0a122346ff0f19320f1919ffffff
 ffffffff00669938ff05013506040232b03072428de89888a585c09faf5a
 ffff06ec060c0003080bffffffffff07ffff0202ff060300fdfd040700fc
 0300fefe0202070e
 root@1:~# sha256sum /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
 428f34d0461876f189ac97f93e68a05fa6428c6650b3b7baf736a921e5898ed1  /sys/bus/spi/devices/spi0.0/spi-nor/sfdp

Please dump the SFDP tables using ``xxd -p``. It enables us to do
the reverse operation and convert the hexdump to binary with
``xxd -rp``. Dumping the SFDP data with ``hexdump -Cv`` is accepted,
but less desirable.
”h]”(hÝ)”}”(hŒDDump the sysfs entries and print the md5/sha1/sha256 SFDP checksum::”h]”hŒCDump the sysfs entries and print the md5/sha1/sha256 SFDP checksum:”…””}”(hjŠ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´K'hj†  ubjo  )”}”(hX‚  root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/partname
sst26vf064b
root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/jedec_id
bf2643
root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/manufacturer
sst
root@1:~# xxd -p /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
53464450060102ff00060110300000ff81000106000100ffbf0001180002
0001fffffffffffffffffffffffffffffffffd20f1ffffffff0344eb086b
083b80bbfeffffffffff00ffffff440b0c200dd80fd810d820914824806f
1d81ed0f773830b030b0f7ffffff29c25cfff030c080ffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffff0004fff37f0000f57f0000f9ff
7d00f57f0000f37f0000ffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffbf2643ffb95ffdff30f260f332ff0a122346ff0f19320f1919ffffff
ffffffff00669938ff05013506040232b03072428de89888a585c09faf5a
ffff06ec060c0003080bffffffffff07ffff0202ff060300fdfd040700fc
0300fefe0202070e
root@1:~# sha256sum /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
428f34d0461876f189ac97f93e68a05fa6428c6650b3b7baf736a921e5898ed1  /sys/bus/spi/devices/spi0.0/spi-nor/sfdp”h]”hX‚  root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/partname
sst26vf064b
root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/jedec_id
bf2643
root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/manufacturer
sst
root@1:~# xxd -p /sys/bus/spi/devices/spi0.0/spi-nor/sfdp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root@1:~# sha256sum /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
428f34d0461876f189ac97f93e68a05fa6428c6650b3b7baf736a921e5898ed1  /sys/bus/spi/devices/spi0.0/spi-nor/sfdp”…””}”hj˜  sbah}”(h]”h ]”h"]”h$]”h&]”j~  j  uh1jn  h³hÊh´K)hj†  ubhÝ)”}”(hŒ×Please dump the SFDP tables using ``xxd -p``. It enables us to do
the reverse operation and convert the hexdump to binary with
``xxd -rp``. Dumping the SFDP data with ``hexdump -Cv`` is accepted,
but less desirable.”h]”(hŒ"Please dump the SFDP tables using ”…””}”(hj¦  h²hh³Nh´Nubj  )”}”(hŒ
``xxd -p``”h]”hŒxxd -p”…””}”(hj®  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j  hj¦  ubhŒS. It enables us to do
the reverse operation and convert the hexdump to binary with
”…””}”(hj¦  h²hh³Nh´Nubj  )”}”(hŒ``xxd -rp``”h]”hŒxxd -rp”…””}”(hjÀ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j  hj¦  ubhŒ. Dumping the SFDP data with ”…””}”(hj¦  h²hh³Nh´Nubj  )”}”(hŒ``hexdump -Cv``”h]”hŒhexdump -Cv”…””}”(hjÒ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j  hj¦  ubhŒ! is accepted,
but less desirable.”…””}”(hj¦  h²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´KHhj†  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jZ  hjW  h²hh³hÊh´Nubj[  )”}”(hX²  Dump debugfs data::

 root@1:~# cat /sys/kernel/debug/spi-nor/spi0.0/capabilities
 Supported read modes by the flash
  1S-1S-1S
   opcode            0x03
   mode cycles       0
   dummy cycles      0
  1S-1S-1S (fast read)
   opcode            0x0b
   mode cycles       0
   dummy cycles      8
  1S-1S-2S
   opcode            0x3b
   mode cycles       0
   dummy cycles      8
  1S-2S-2S
   opcode            0xbb
   mode cycles       4
   dummy cycles      0
  1S-1S-4S
   opcode            0x6b
   mode cycles       0
   dummy cycles      8
  1S-4S-4S
   opcode            0xeb
   mode cycles       2
   dummy cycles      4
  4S-4S-4S
   opcode            0x0b
   mode cycles       2
   dummy cycles      4

 Supported page program modes by the flash
  1S-1S-1S
   opcode    0x02

 root@1:~# cat /sys/kernel/debug/spi-nor/spi0.0/params
 name                sst26vf064b
 id                  bf 26 43 bf 26 43
 size                8.00 MiB
 write size          1
 page size           256
 address nbytes      3
 flags               HAS_LOCK | HAS_16BIT_SR | SOFT_RESET | SWP_IS_VOLATILE

 opcodes
  read               0xeb
   dummy cycles      6
  erase              0x20
  program            0x02
  8D extension       none

 protocols
  read               1S-4S-4S
  write              1S-1S-1S
  register           1S-1S-1S

 erase commands
  20 (4.00 KiB) [0]
  d8 (8.00 KiB) [1]
  d8 (32.0 KiB) [2]
  d8 (64.0 KiB) [3]
  c7 (8.00 MiB)

 sector map
  region (in hex)   | erase mask | flags
  ------------------+------------+----------
  00000000-00007fff |     [01  ] |
  00008000-0000ffff |     [0 2 ] |
  00010000-007effff |     [0  3] |
  007f0000-007f7fff |     [0 2 ] |
  007f8000-007fffff |     [01  ] |
”h]”(hÝ)”}”(hŒDump debugfs data::”h]”hŒDump debugfs data:”…””}”(hjô  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´KMhjð  ubjo  )”}”(hX[  root@1:~# cat /sys/kernel/debug/spi-nor/spi0.0/capabilities
Supported read modes by the flash
 1S-1S-1S
  opcode            0x03
  mode cycles       0
  dummy cycles      0
 1S-1S-1S (fast read)
  opcode            0x0b
  mode cycles       0
  dummy cycles      8
 1S-1S-2S
  opcode            0x3b
  mode cycles       0
  dummy cycles      8
 1S-2S-2S
  opcode            0xbb
  mode cycles       4
  dummy cycles      0
 1S-1S-4S
  opcode            0x6b
  mode cycles       0
  dummy cycles      8
 1S-4S-4S
  opcode            0xeb
  mode cycles       2
  dummy cycles      4
 4S-4S-4S
  opcode            0x0b
  mode cycles       2
  dummy cycles      4

Supported page program modes by the flash
 1S-1S-1S
  opcode    0x02

root@1:~# cat /sys/kernel/debug/spi-nor/spi0.0/params
name                sst26vf064b
id                  bf 26 43 bf 26 43
size                8.00 MiB
write size          1
page size           256
address nbytes      3
flags               HAS_LOCK | HAS_16BIT_SR | SOFT_RESET | SWP_IS_VOLATILE

opcodes
 read               0xeb
  dummy cycles      6
 erase              0x20
 program            0x02
 8D extension       none

protocols
 read               1S-4S-4S
 write              1S-1S-1S
 register           1S-1S-1S

erase commands
 20 (4.00 KiB) [0]
 d8 (8.00 KiB) [1]
 d8 (32.0 KiB) [2]
 d8 (64.0 KiB) [3]
 c7 (8.00 MiB)

sector map
 region (in hex)   | erase mask | flags
 ------------------+------------+----------
 00000000-00007fff |     [01  ] |
 00008000-0000ffff |     [0 2 ] |
 00010000-007effff |     [0  3] |
 007f0000-007f7fff |     [0 2 ] |
 007f8000-007fffff |     [01  ] |”h]”hX[  root@1:~# cat /sys/kernel/debug/spi-nor/spi0.0/capabilities
Supported read modes by the flash
 1S-1S-1S
  opcode            0x03
  mode cycles       0
  dummy cycles      0
 1S-1S-1S (fast read)
  opcode            0x0b
  mode cycles       0
  dummy cycles      8
 1S-1S-2S
  opcode            0x3b
  mode cycles       0
  dummy cycles      8
 1S-2S-2S
  opcode            0xbb
  mode cycles       4
  dummy cycles      0
 1S-1S-4S
  opcode            0x6b
  mode cycles       0
  dummy cycles      8
 1S-4S-4S
  opcode            0xeb
  mode cycles       2
  dummy cycles      4
 4S-4S-4S
  opcode            0x0b
  mode cycles       2
  dummy cycles      4

Supported page program modes by the flash
 1S-1S-1S
  opcode    0x02

root@1:~# cat /sys/kernel/debug/spi-nor/spi0.0/params
name                sst26vf064b
id                  bf 26 43 bf 26 43
size                8.00 MiB
write size          1
page size           256
address nbytes      3
flags               HAS_LOCK | HAS_16BIT_SR | SOFT_RESET | SWP_IS_VOLATILE

opcodes
 read               0xeb
  dummy cycles      6
 erase              0x20
 program            0x02
 8D extension       none

protocols
 read               1S-4S-4S
 write              1S-1S-1S
 register           1S-1S-1S

erase commands
 20 (4.00 KiB) [0]
 d8 (8.00 KiB) [1]
 d8 (32.0 KiB) [2]
 d8 (64.0 KiB) [3]
 c7 (8.00 MiB)

sector map
 region (in hex)   | erase mask | flags
 ------------------+------------+----------
 00000000-00007fff |     [01  ] |
 00008000-0000ffff |     [0 2 ] |
 00010000-007effff |     [0  3] |
 007f0000-007f7fff |     [0 2 ] |
 007f8000-007fffff |     [01  ] |”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”j~  j  uh1jn  h³hÊh´KOhjð  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jZ  hjW  h²hh³hÊh´Nubj[  )”}”(hX[  Use `mtd-utils <https://git.infradead.org/mtd-utils.git>`__
and verify that erase, read and page program operations work fine::

 root@1:~# dd if=/dev/urandom of=./spi_test bs=1M count=2
 2+0 records in
 2+0 records out
 2097152 bytes (2.1 MB, 2.0 MiB) copied, 0.848566 s, 2.5 MB/s

 root@1:~# mtd_debug erase /dev/mtd0 0 2097152
 Erased 2097152 bytes from address 0x00000000 in flash

 root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
 Copied 2097152 bytes from address 0x00000000 in flash to spi_read

 root@1:~# hexdump spi_read
 0000000 ffff ffff ffff ffff ffff ffff ffff ffff
 *
 0200000

 root@1:~# sha256sum spi_read
 4bda3a28f4ffe603c0ec1258c0034d65a1a0d35ab7bd523a834608adabf03cc5  spi_read

 root@1:~# mtd_debug write /dev/mtd0 0 2097152 spi_test
 Copied 2097152 bytes from spi_test to address 0x00000000 in flash

 root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
 Copied 2097152 bytes from address 0x00000000 in flash to spi_read

 root@1:~# sha256sum spi*
 c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
 c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test

If the flash comes erased by default and the previous erase was ignored,
we won't catch it, thus test the erase again::

 root@1:~# mtd_debug erase /dev/mtd0 0 2097152
 Erased 2097152 bytes from address 0x00000000 in flash

 root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
 Copied 2097152 bytes from address 0x00000000 in flash to spi_read

 root@1:~# sha256sum spi*
 4bda3a28f4ffe603c0ec1258c0034d65a1a0d35ab7bd523a834608adabf03cc5  spi_read
 c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test

Dump some other relevant data::

 root@1:~# mtd_debug info /dev/mtd0
 mtd.type = MTD_NORFLASH
 mtd.flags = MTD_CAP_NORFLASH
 mtd.size = 8388608 (8M)
 mtd.erasesize = 4096 (4K)
 mtd.writesize = 1
 mtd.oobsize = 0
 regions = 0
”h]”(hÝ)”}”(hŒUse `mtd-utils <https://git.infradead.org/mtd-utils.git>`__
and verify that erase, read and page program operations work fine::”h]”(hŒUse ”…””}”(hj  h²hh³Nh´NubhŒ	reference”“”)”}”(hŒ7`mtd-utils <https://git.infradead.org/mtd-utils.git>`__”h]”hŒ	mtd-utils”…””}”(hj$  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”Œname”Œ	mtd-utils”Œrefuri”Œ'https://git.infradead.org/mtd-utils.git”uh1j"  hj  ubhŒC
and verify that erase, read and page program operations work fine:”…””}”(hj  h²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´K—hj  ubjo  )”}”(hXÔ  root@1:~# dd if=/dev/urandom of=./spi_test bs=1M count=2
2+0 records in
2+0 records out
2097152 bytes (2.1 MB, 2.0 MiB) copied, 0.848566 s, 2.5 MB/s

root@1:~# mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash

root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
Copied 2097152 bytes from address 0x00000000 in flash to spi_read

root@1:~# hexdump spi_read
0000000 ffff ffff ffff ffff ffff ffff ffff ffff
*
0200000

root@1:~# sha256sum spi_read
4bda3a28f4ffe603c0ec1258c0034d65a1a0d35ab7bd523a834608adabf03cc5  spi_read

root@1:~# mtd_debug write /dev/mtd0 0 2097152 spi_test
Copied 2097152 bytes from spi_test to address 0x00000000 in flash

root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
Copied 2097152 bytes from address 0x00000000 in flash to spi_read

root@1:~# sha256sum spi*
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test”h]”hXÔ  root@1:~# dd if=/dev/urandom of=./spi_test bs=1M count=2
2+0 records in
2+0 records out
2097152 bytes (2.1 MB, 2.0 MiB) copied, 0.848566 s, 2.5 MB/s

root@1:~# mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash

root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
Copied 2097152 bytes from address 0x00000000 in flash to spi_read

root@1:~# hexdump spi_read
0000000 ffff ffff ffff ffff ffff ffff ffff ffff
*
0200000

root@1:~# sha256sum spi_read
4bda3a28f4ffe603c0ec1258c0034d65a1a0d35ab7bd523a834608adabf03cc5  spi_read

root@1:~# mtd_debug write /dev/mtd0 0 2097152 spi_test
Copied 2097152 bytes from spi_test to address 0x00000000 in flash

root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
Copied 2097152 bytes from address 0x00000000 in flash to spi_read

root@1:~# sha256sum spi*
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test”…””}”hj@  sbah}”(h]”h ]”h"]”h$]”h&]”j~  j  uh1jn  h³hÊh´Kšhj  ubhÝ)”}”(hŒwIf the flash comes erased by default and the previous erase was ignored,
we won't catch it, thus test the erase again::”h]”hŒxIf the flash comes erased by default and the previous erase was ignored,
we wonâ€™t catch it, thus test the erase again:”…””}”(hjN  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´K·hj  ubjo  )”}”(hXŒ  root@1:~# mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash

root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
Copied 2097152 bytes from address 0x00000000 in flash to spi_read

root@1:~# sha256sum spi*
4bda3a28f4ffe603c0ec1258c0034d65a1a0d35ab7bd523a834608adabf03cc5  spi_read
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test”h]”hXŒ  root@1:~# mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash

root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
Copied 2097152 bytes from address 0x00000000 in flash to spi_read

root@1:~# sha256sum spi*
4bda3a28f4ffe603c0ec1258c0034d65a1a0d35ab7bd523a834608adabf03cc5  spi_read
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test”…””}”hj\  sbah}”(h]”h ]”h"]”h$]”h&]”j~  j  uh1jn  h³hÊh´Kºhj  ubhÝ)”}”(hŒDump some other relevant data::”h]”hŒDump some other relevant data:”…””}”(hjj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´KÄhj  ubjo  )”}”(hŒ·root@1:~# mtd_debug info /dev/mtd0
mtd.type = MTD_NORFLASH
mtd.flags = MTD_CAP_NORFLASH
mtd.size = 8388608 (8M)
mtd.erasesize = 4096 (4K)
mtd.writesize = 1
mtd.oobsize = 0
regions = 0”h]”hŒ·root@1:~# mtd_debug info /dev/mtd0
mtd.type = MTD_NORFLASH
mtd.flags = MTD_CAP_NORFLASH
mtd.size = 8388608 (8M)
mtd.erasesize = 4096 (4K)
mtd.writesize = 1
mtd.oobsize = 0
regions = 0”…””}”hjx  sbah}”(h]”h ]”h"]”h$]”h&]”j~  j  uh1jn  h³hÊh´KÆhj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jZ  hjW  h²hh³hÊh´Nubj[  )”}”(hX½  If your flash supports locking, please go through the following test
procedure to make sure it correctly behaves. The below example
expects the typical situation where eraseblocks and lock sectors have
the same size. In case you enabled MTD_SPI_NOR_USE_4K_SECTORS, you
must adapt `bs` accordingly.

Warning: These tests may hard lock your device! Make sure:

- The device is not hard locked already (#WP strapped to low and
  SR_SRWD bit set)
- If you have a WPn pin, you may want to set `no-wp` in your DT for
  the time of the test, to only make use of software protection.
  Otherwise, clearing the locking state depends on the WPn
  signal and if it is tied to low, the flash will be permanently
  locked.

Test full chip locking and make sure expectations, the MEMISLOCKED
ioctl output, the debugfs output and experimental results are all
aligned::

 root@1:~# alias show_sectors='grep -A4 "locked sectors" /sys/kernel/debug/spi-nor/spi0.0/params'
 root@1:~# flash_lock -u /dev/mtd0
 root@1:~# flash_lock -i /dev/mtd0
 Device: /dev/mtd0
 Start: 0
 Len: 0x4000000
 Lock status: unlocked
 Return code: 0
 root@1:~# mtd_debug erase /dev/mtd0 0 2097152
 Erased 2097152 bytes from address 0x00000000 in flash
 root@1:~# mtd_debug write /dev/mtd0 0 2097152 spi_test
 Copied 2097152 bytes from spi_test to address 0x00000000 in flash
 root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
 Copied 2097152 bytes from address 0x00000000 in flash to spi_read
 root@1:~# sha256sum spi*
 c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
 c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test
 root@1:~# show_sectors
 software locked sectors
  region (in hex)   | status   | #sectors
  ------------------+----------+---------
  00000000-03ffffff | unlocked | 1024

 root@1:~# flash_lock -l /dev/mtd0
 root@1:~# flash_lock -i /dev/mtd0
 Device: /dev/mtd0
 Start: 0
 Len: 0x4000000
 Lock status: locked
 Return code: 1
 root@1:~# mtd_debug erase /dev/mtd0 0 2097152
 Erased 2097152 bytes from address 0x00000000 in flash
 root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
 Copied 2097152 bytes from address 0x00000000 in flash to spi_read
 root@1:~# sha256sum spi*
 c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
 c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test
 root@1:~# dd if=/dev/urandom of=./spi_test2 bs=1M count=2
 2+0 records in
 2+0 records out
 root@1:~# mtd_debug write /dev/mtd0 0 2097152 spi_test2
 Copied 2097152 bytes from spi_test2 to address 0x00000000 in flash
 root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read2
 Copied 2097152 bytes from address 0x00000000 in flash to spi_read2
 root@1:~# sha256sum spi*
 c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
 c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read2
 c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test
 bea9334df51c620440f86751cba0799214a016329f1736f9456d40cf40efdc88  spi_test2
 root@1:~# show_sectors
 software locked sectors
  region (in hex)   | status   | #sectors
  ------------------+----------+---------
  00000000-03ffffff |   locked | 1024
 root@1:~# flash_lock -u /dev/mtd0

Once we trust the debugfs output we can use it to test various
situations. Check top locking/unlocking (end of the device)::

 root@1:~# size=$(cat /sys/class/mtd/mtd0/size)
 root@1:~# bs=$(cat /sys/class/mtd/mtd0/erasesize)
 root@1:~# nsectors=$(grep unlocked /sys/kernel/debug/spi-nor/spi0.0/params | sed -e 's/.*unlocked | //')
 root@1:~# ss=$(($size / $nsectors))
 root@1:~# bps=$(($ss / $bs))

 root@1:~# flash_lock -u /dev/mtd0
 root@1:~# flash_lock -l /dev/mtd0 $(($size - (2 * $ss))) $((2 * $bps)) # last two
 root@1:~# show_sectors
 software locked sectors
  region (in hex)   | status   | #sectors
  ------------------+----------+---------
  00000000-03fdffff | unlocked | 1022
  03fe0000-03ffffff |   locked | 2
 root@1:~# flash_lock -u /dev/mtd0 $(($size - (2 * $ss))) $((1 * $bps)) # last one
 root@1:~# show_sectors
 software locked sectors
  region (in hex)   | status   | #sectors
  ------------------+----------+---------
  00000000-03feffff | unlocked | 1023
  03ff0000-03ffffff |   locked | 1

If the flash features 4 block protection bits (BP), we can protect
more than 4MB (typically 128 64kiB-blocks or more), with a finer
grain than locking the entire device::

 root@1:~# flash_lock -u /dev/mtd0
 root@1:~# flash_lock -l /dev/mtd0 $(($size - (2**7 * $ss))) $((2**7 * $bps))
 root@1:~# show_sectors
 software locked sectors
  region (in hex)   | status   | #sectors
  ------------------+----------+---------
  00000000-037fffff | unlocked | 896
  03800000-03ffffff |   locked | 128

If the flash features a Top/Bottom (TB) bit, we can protect the
beginning of the flash::

 root@1:~# flash_lock -u /dev/mtd0
 root@1:~# flash_lock -l /dev/mtd0 0 $((2 * $bps)) # first two
 root@1:~# show_sectors
 software locked sectors
  region (in hex)   | status   | #sectors
  ------------------+----------+---------
  00000000-0001ffff |   locked | 2
  00020000-03ffffff | unlocked | 1022
 root@1:~# flash_lock -u /dev/mtd0 $ss $((1 * $bps)) # first one
 root@1:~# show_sectors
 software locked sectors
  region (in hex)   | status   | #sectors
  ------------------+----------+---------
  00000000-0000ffff |   locked | 1
  00010000-03ffffff | unlocked | 1023

If the flash features a Complement (CMP) bit, we can protect with
more granularity above half of the capacity. Let's lock all but one
block, then unlock one more block::

 root@1:~# all_but_one=$((($size / $bs) - ($ss / $bs)))

 root@1:~# flash_lock -u /dev/mtd0
 root@1:~# flash_lock -l /dev/mtd0 $ss $all_but_one # all but the first
 root@1:~# show_sectors
 software locked sectors
  region (in hex)   | status   | #sectors
  ------------------+----------+---------
  00000000-0000ffff | unlocked | 1
  00010000-03ffffff |   locked | 1023
 root@1:~# flash_lock -u /dev/mtd0 $ss $(($ss / $bs)) # all but the two first
 root@1:~# show_sectors
 software locked sectors
  region (in hex)   | status   | #sectors
  ------------------+----------+---------
  00000000-0001ffff | unlocked | 2
  00020000-03ffffff |   locked | 1022
 root@1:~# flash_lock -u /dev/mtd0
 root@1:~# flash_lock -l /dev/mtd0 0 $all_but_one # same from the other side
 root@1:~# show_sectors
 software locked sectors
  region (in hex)   | status   | #sectors
  ------------------+----------+---------
  00000000-03feffff |   locked | 1023
  03ff0000-03ffffff | unlocked | 1
 root@1:~# flash_lock -u /dev/mtd0 $(($size - (2 * $ss))) $(($ss / $bs)) # all but two
 root@1:~# show_sectors
 software locked sectors
  region (in hex)   | status   | #sectors
  ------------------+----------+---------
  00000000-03fdffff |   locked | 1022
  03fe0000-03ffffff | unlocked | 2”h]”(hÝ)”}”(hX)  If your flash supports locking, please go through the following test
procedure to make sure it correctly behaves. The below example
expects the typical situation where eraseblocks and lock sectors have
the same size. In case you enabled MTD_SPI_NOR_USE_4K_SECTORS, you
must adapt `bs` accordingly.”h]”(hX  If your flash supports locking, please go through the following test
procedure to make sure it correctly behaves. The below example
expects the typical situation where eraseblocks and lock sectors have
the same size. In case you enabled MTD_SPI_NOR_USE_4K_SECTORS, you
must adapt ”…””}”(hj  h²hh³Nh´NubhŒtitle_reference”“”)”}”(hŒ`bs`”h]”hŒbs”…””}”(hjš  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j˜  hj  ubhŒ accordingly.”…””}”(hj  h²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´KÏhjŒ  ubhÝ)”}”(hŒ:Warning: These tests may hard lock your device! Make sure:”h]”hŒ:Warning: These tests may hard lock your device! Make sure:”…””}”(hj²  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´KÕhjŒ  ubhŒbullet_list”“”)”}”(hhh]”(j[  )”}”(hŒOThe device is not hard locked already (#WP strapped to low and
SR_SRWD bit set)”h]”hÝ)”}”(hŒOThe device is not hard locked already (#WP strapped to low and
SR_SRWD bit set)”h]”hŒOThe device is not hard locked already (#WP strapped to low and
SR_SRWD bit set)”…””}”(hjÉ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´K×hjÅ  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jZ  hjÂ  ubj[  )”}”(hX  If you have a WPn pin, you may want to set `no-wp` in your DT for
the time of the test, to only make use of software protection.
Otherwise, clearing the locking state depends on the WPn
signal and if it is tied to low, the flash will be permanently
locked.
”h]”hÝ)”}”(hX   If you have a WPn pin, you may want to set `no-wp` in your DT for
the time of the test, to only make use of software protection.
Otherwise, clearing the locking state depends on the WPn
signal and if it is tied to low, the flash will be permanently
locked.”h]”(hŒ+If you have a WPn pin, you may want to set ”…””}”(hjá  h²hh³Nh´Nubj™  )”}”(hŒ`no-wp`”h]”hŒno-wp”…””}”(hjé  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j˜  hjá  ubhŒÎ in your DT for
the time of the test, to only make use of software protection.
Otherwise, clearing the locking state depends on the WPn
signal and if it is tied to low, the flash will be permanently
locked.”…””}”(hjá  h²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´KÙhjÝ  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jZ  hjÂ  ubeh}”(h]”h ]”h"]”h$]”h&]”Œbullet”Œ-”uh1jÀ  h³hÊh´K×hjŒ  ubhÝ)”}”(hŒŽTest full chip locking and make sure expectations, the MEMISLOCKED
ioctl output, the debugfs output and experimental results are all
aligned::”h]”hŒTest full chip locking and make sure expectations, the MEMISLOCKED
ioctl output, the debugfs output and experimental results are all
aligned:”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´KßhjŒ  ubjo  )”}”(hX	  root@1:~# alias show_sectors='grep -A4 "locked sectors" /sys/kernel/debug/spi-nor/spi0.0/params'
root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -i /dev/mtd0
Device: /dev/mtd0
Start: 0
Len: 0x4000000
Lock status: unlocked
Return code: 0
root@1:~# mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash
root@1:~# mtd_debug write /dev/mtd0 0 2097152 spi_test
Copied 2097152 bytes from spi_test to address 0x00000000 in flash
root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
Copied 2097152 bytes from address 0x00000000 in flash to spi_read
root@1:~# sha256sum spi*
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03ffffff | unlocked | 1024

root@1:~# flash_lock -l /dev/mtd0
root@1:~# flash_lock -i /dev/mtd0
Device: /dev/mtd0
Start: 0
Len: 0x4000000
Lock status: locked
Return code: 1
root@1:~# mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash
root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
Copied 2097152 bytes from address 0x00000000 in flash to spi_read
root@1:~# sha256sum spi*
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test
root@1:~# dd if=/dev/urandom of=./spi_test2 bs=1M count=2
2+0 records in
2+0 records out
root@1:~# mtd_debug write /dev/mtd0 0 2097152 spi_test2
Copied 2097152 bytes from spi_test2 to address 0x00000000 in flash
root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read2
Copied 2097152 bytes from address 0x00000000 in flash to spi_read2
root@1:~# sha256sum spi*
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read2
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test
bea9334df51c620440f86751cba0799214a016329f1736f9456d40cf40efdc88  spi_test2
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03ffffff |   locked | 1024
root@1:~# flash_lock -u /dev/mtd0”h]”hX	  root@1:~# alias show_sectors='grep -A4 "locked sectors" /sys/kernel/debug/spi-nor/spi0.0/params'
root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -i /dev/mtd0
Device: /dev/mtd0
Start: 0
Len: 0x4000000
Lock status: unlocked
Return code: 0
root@1:~# mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash
root@1:~# mtd_debug write /dev/mtd0 0 2097152 spi_test
Copied 2097152 bytes from spi_test to address 0x00000000 in flash
root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
Copied 2097152 bytes from address 0x00000000 in flash to spi_read
root@1:~# sha256sum spi*
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03ffffff | unlocked | 1024

root@1:~# flash_lock -l /dev/mtd0
root@1:~# flash_lock -i /dev/mtd0
Device: /dev/mtd0
Start: 0
Len: 0x4000000
Lock status: locked
Return code: 1
root@1:~# mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash
root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read
Copied 2097152 bytes from address 0x00000000 in flash to spi_read
root@1:~# sha256sum spi*
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test
root@1:~# dd if=/dev/urandom of=./spi_test2 bs=1M count=2
2+0 records in
2+0 records out
root@1:~# mtd_debug write /dev/mtd0 0 2097152 spi_test2
Copied 2097152 bytes from spi_test2 to address 0x00000000 in flash
root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read2
Copied 2097152 bytes from address 0x00000000 in flash to spi_read2
root@1:~# sha256sum spi*
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_read2
c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8  spi_test
bea9334df51c620440f86751cba0799214a016329f1736f9456d40cf40efdc88  spi_test2
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03ffffff |   locked | 1024
root@1:~# flash_lock -u /dev/mtd0”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”j~  j  uh1jn  h³hÊh´KãhjŒ  ubhÝ)”}”(hŒ|Once we trust the debugfs output we can use it to test various
situations. Check top locking/unlocking (end of the device)::”h]”hŒ{Once we trust the debugfs output we can use it to test various
situations. Check top locking/unlocking (end of the device):”…””}”(hj+  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´MhjŒ  ubjo  )”}”(hXa  root@1:~# size=$(cat /sys/class/mtd/mtd0/size)
root@1:~# bs=$(cat /sys/class/mtd/mtd0/erasesize)
root@1:~# nsectors=$(grep unlocked /sys/kernel/debug/spi-nor/spi0.0/params | sed -e 's/.*unlocked | //')
root@1:~# ss=$(($size / $nsectors))
root@1:~# bps=$(($ss / $bs))

root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -l /dev/mtd0 $(($size - (2 * $ss))) $((2 * $bps)) # last two
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03fdffff | unlocked | 1022
 03fe0000-03ffffff |   locked | 2
root@1:~# flash_lock -u /dev/mtd0 $(($size - (2 * $ss))) $((1 * $bps)) # last one
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03feffff | unlocked | 1023
 03ff0000-03ffffff |   locked | 1”h]”hXa  root@1:~# size=$(cat /sys/class/mtd/mtd0/size)
root@1:~# bs=$(cat /sys/class/mtd/mtd0/erasesize)
root@1:~# nsectors=$(grep unlocked /sys/kernel/debug/spi-nor/spi0.0/params | sed -e 's/.*unlocked | //')
root@1:~# ss=$(($size / $nsectors))
root@1:~# bps=$(($ss / $bs))

root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -l /dev/mtd0 $(($size - (2 * $ss))) $((2 * $bps)) # last two
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03fdffff | unlocked | 1022
 03fe0000-03ffffff |   locked | 2
root@1:~# flash_lock -u /dev/mtd0 $(($size - (2 * $ss))) $((1 * $bps)) # last one
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03feffff | unlocked | 1023
 03ff0000-03ffffff |   locked | 1”…””}”hj9  sbah}”(h]”h ]”h"]”h$]”h&]”j~  j  uh1jn  h³hÊh´MhjŒ  ubhÝ)”}”(hŒªIf the flash features 4 block protection bits (BP), we can protect
more than 4MB (typically 128 64kiB-blocks or more), with a finer
grain than locking the entire device::”h]”hŒ©If the flash features 4 block protection bits (BP), we can protect
more than 4MB (typically 128 64kiB-blocks or more), with a finer
grain than locking the entire device:”…””}”(hjG  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´M4hjŒ  ubjo  )”}”(hX7  root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -l /dev/mtd0 $(($size - (2**7 * $ss))) $((2**7 * $bps))
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-037fffff | unlocked | 896
 03800000-03ffffff |   locked | 128”h]”hX7  root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -l /dev/mtd0 $(($size - (2**7 * $ss))) $((2**7 * $bps))
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-037fffff | unlocked | 896
 03800000-03ffffff |   locked | 128”…””}”hjU  sbah}”(h]”h ]”h"]”h$]”h&]”j~  j  uh1jn  h³hÊh´M8hjŒ  ubhÝ)”}”(hŒXIf the flash features a Top/Bottom (TB) bit, we can protect the
beginning of the flash::”h]”hŒWIf the flash features a Top/Bottom (TB) bit, we can protect the
beginning of the flash:”…””}”(hjc  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´MAhjŒ  ubjo  )”}”(hX/  root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -l /dev/mtd0 0 $((2 * $bps)) # first two
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-0001ffff |   locked | 2
 00020000-03ffffff | unlocked | 1022
root@1:~# flash_lock -u /dev/mtd0 $ss $((1 * $bps)) # first one
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-0000ffff |   locked | 1
 00010000-03ffffff | unlocked | 1023”h]”hX/  root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -l /dev/mtd0 0 $((2 * $bps)) # first two
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-0001ffff |   locked | 2
 00020000-03ffffff | unlocked | 1022
root@1:~# flash_lock -u /dev/mtd0 $ss $((1 * $bps)) # first one
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-0000ffff |   locked | 1
 00010000-03ffffff | unlocked | 1023”…””}”hjq  sbah}”(h]”h ]”h"]”h$]”h&]”j~  j  uh1jn  h³hÊh´MDhjŒ  ubhÝ)”}”(hŒ©If the flash features a Complement (CMP) bit, we can protect with
more granularity above half of the capacity. Let's lock all but one
block, then unlock one more block::”h]”hŒªIf the flash features a Complement (CMP) bit, we can protect with
more granularity above half of the capacity. Letâ€™s lock all but one
block, then unlock one more block:”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÜh³hÊh´MThjŒ  ubjo  )”}”(hXÑ  root@1:~# all_but_one=$((($size / $bs) - ($ss / $bs)))

root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -l /dev/mtd0 $ss $all_but_one # all but the first
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-0000ffff | unlocked | 1
 00010000-03ffffff |   locked | 1023
root@1:~# flash_lock -u /dev/mtd0 $ss $(($ss / $bs)) # all but the two first
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-0001ffff | unlocked | 2
 00020000-03ffffff |   locked | 1022
root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -l /dev/mtd0 0 $all_but_one # same from the other side
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03feffff |   locked | 1023
 03ff0000-03ffffff | unlocked | 1
root@1:~# flash_lock -u /dev/mtd0 $(($size - (2 * $ss))) $(($ss / $bs)) # all but two
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03fdffff |   locked | 1022
 03fe0000-03ffffff | unlocked | 2”h]”hXÑ  root@1:~# all_but_one=$((($size / $bs) - ($ss / $bs)))

root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -l /dev/mtd0 $ss $all_but_one # all but the first
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-0000ffff | unlocked | 1
 00010000-03ffffff |   locked | 1023
root@1:~# flash_lock -u /dev/mtd0 $ss $(($ss / $bs)) # all but the two first
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-0001ffff | unlocked | 2
 00020000-03ffffff |   locked | 1022
root@1:~# flash_lock -u /dev/mtd0
root@1:~# flash_lock -l /dev/mtd0 0 $all_but_one # same from the other side
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03feffff |   locked | 1023
 03ff0000-03ffffff | unlocked | 1
root@1:~# flash_lock -u /dev/mtd0 $(($size - (2 * $ss))) $(($ss / $bs)) # all but two
root@1:~# show_sectors
software locked sectors
 region (in hex)   | status   | #sectors
 ------------------+----------+---------
 00000000-03fdffff |   locked | 1022
 03fe0000-03ffffff | unlocked | 2”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”j~  j  uh1jn  h³hÊh´MXhjŒ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jZ  hjW  h²hh³hÊh´Nubeh}”(h]”h ]”h"]”h$]”h&]”Œenumtype”Œarabic”Œprefix”hŒsuffix”Œ)”uh1jU  hj$  h²hh³hÊh´K!ubeh}”(h]”Œminimum-testing-requirements”ah ]”h"]”Œminimum testing requirements”ah$]”h&]”uh1hµhh·h²hh³hÊh´Kubeh}”(h]”Œspi-nor-framework”ah ]”h"]”Œspi nor framework”ah$]”h&]”uh1hµhhh²hh³hÊh´Kubeh}”(h]”h ]”h"]”h$]”h&]”Œsource”hÊuh1hŒcurrent_source”NŒcurrent_line”NŒsettings”Œdocutils.frontend”ŒValues”“”)”}”(hºNŒ	generator”NŒ	datestamp”NŒsource_link”NŒ
source_url”NŒtoc_backlinks”Œentry”Œfootnote_backlinks”KŒsectnum_xform”KŒstrip_comments”NŒstrip_elements_with_classes”NŒstrip_classes”NŒreport_level”KŒ
halt_level”KŒexit_status_level”KŒdebug”NŒwarning_stream”NŒ	traceback”ˆŒinput_encoding”Œ	utf-8-sig”Œinput_encoding_error_handler”Œstrict”Œoutput_encoding”Œutf-8”Œoutput_encoding_error_handler”jß  Œerror_encoding”Œutf-8”Œerror_encoding_error_handler”Œbackslashreplace”Œlanguage_code”Œen”Œrecord_dependencies”NŒconfig”NŒ	id_prefix”hŒauto_id_prefix”Œid”Œdump_settings”NŒdump_internals”NŒdump_transforms”NŒdump_pseudo_xml”NŒexpose_internals”NŒstrict_visitor”NŒ_disable_config”NŒ_source”hÊŒ_destination”NŒ_config_files”]”Œ7/var/lib/git/docbuild/linux/Documentation/docutils.conf”aŒfile_insertion_enabled”ˆŒraw_enabled”KŒline_length_limit”M'Œpep_references”NŒpep_base_url”Œhttps://peps.python.org/”Œpep_file_url_template”Œpep-%04d”Œrfc_references”NŒrfc_base_url”Œ&https://datatracker.ietf.org/doc/html/”Œ	tab_width”KŒtrim_footnote_reference_space”‰Œsyntax_highlight”Œlong”Œsmart_quotes”ˆŒsmartquotes_locales”]”Œcharacter_level_inline_markup”‰Œdoctitle_xform”‰Œdocinfo_xform”KŒsectsubtitle_xform”‰Œimage_loading”Œlink”Œembed_stylesheet”‰Œcloak_email_addresses”ˆŒsection_self_link”‰Œenv”NubŒreporter”NŒindirect_targets”]”Œsubstitution_defs”}”Œsubstitution_names”}”Œrefnames”}”Œrefids”}”Œnameids”}”(j¹  j¶  j!  j  j±  j®  uŒ	nametypes”}”(j¹  ‰j!  ‰j±  ‰uh}”(j¶  h·j  hËj®  j$  uŒfootnote_refs”}”Œcitation_refs”}”Œautofootnotes”]”Œautofootnote_refs”]”Œsymbol_footnotes”]”Œsymbol_footnote_refs”]”Œ	footnotes”]”Œ	citations”]”Œautofootnote_start”KŒsymbol_footnote_start”K Œ
id_counter”Œcollections”ŒCounter”“”}”…”R”Œparse_messages”]”Œtransform_messages”]”Œtransformer”NŒinclude_log”]”Œ
decoration”Nh²hub.