driver-api/mtd/spi-nor.rst

2 SPI NOR framework
6 -----------------------------------
8 Most SPI NOR flashes comply with the JEDEC JESD216
11 standard set of internal read-only parameter tables.
13 The SPI NOR driver queries the SFDP tables in order to determine the
17 on its SFDP data. All one has to do is to specify the "jedec,spi-nor"
28 -----------------------------
31 section, after the ``---`` marker.
37     frequency using the Z (put compatible) SPI controller.
41     root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/partname
43     root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/jedec_id
45     root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/manufacturer
47     root@1:~# xxd -p /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
69     root@1:~# sha256sum /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
70 …0461876f189ac97f93e68a05fa6428c6650b3b7baf736a921e5898ed1  /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
72    Please dump the SFDP tables using ``xxd -p``. It enables us to do
74    ``xxd -rp``. Dumping the SFDP data with ``hexdump -Cv`` is accepted,
79     root@1:~# cat /sys/kernel/debug/spi-nor/spi0.0/capabilities
81      1S-1S-1S
85      1S-1S-1S (fast read)
89      1S-1S-2S
93      1S-2S-2S
97      1S-1S-4S
101      1S-4S-4S
105      4S-4S-4S
111      1S-1S-1S
114     root@1:~# cat /sys/kernel/debug/spi-nor/spi0.0/params
131      read		1S-4S-4S
132      write		1S-1S-1S
133      register		1S-1S-1S
144      ------------------+------------+----------
145      00000000-00007fff |     [01  ] |
146      00008000-0000ffff |     [0 2 ] |
147      00010000-007effff |     [0  3] |
148      007f0000-007f7fff |     [0 2 ] |
149      007f8000-007fffff |     [01  ] |
151 4) Use `mtd-utils <https://git.infradead.org/mtd-utils.git>`__
179     root@1:~# sha256sum spi*
192     root@1:~# sha256sum spi*