Are you calling my a liar?If you have a Pi M.2 HAT+ and if you really want to see for yourself what the EEPROM contains and whether it specifies a DT overlay, you can just dump and decode the contents yourself:
..
read the HAT+ spec as well as the M.2 HAT spec (it's even written on the schematic): the I2C address needs (!) to be 0x51..
3. eepflash.sh --read --device=0 --address=0x50 -t=24c32 -f hat_eeprom_dump.eep (note address might instead be 0x51; not sure if they're specifying it as a stackable HAT)
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Code:
pi@raspberrypi:~ $ sudo i2cdetect -y 1 0 1 2 3 4 5 6 7 8 9 a b c d e f00: -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 50: -- 51 -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- -- ID_SC/ID_SA were connected to ic2_arm on the DUT (CM4, used only for reading the EEPROM).
I'm using a custom overlay for I2C access:
Code:
// Simple EEPROM overlay// // at24compatible-eeprom-overlay.dts#include <dt-bindings/gpio/gpio.h>#include <dt-bindings/pinctrl/bcm2835.h>/dts-v1/;/plugin/;/ {compatible = "brcm,bcm2711";fragment@0 {target = <&gpio>;__overlay__ {e2prom_pins: e2prom_pins { brcm,pins = <4>; brcm,function = <1>; /* out */};};}; fragment@1 {target = <&i2c1>;__overlay__ { pinctrl-names = "default"; pinctrl-0 = <&i2c1_pins>; status = "okay"; at24@51 {compatible = "atmel,24c32","at24";#address-cells = <1>;#size-cells = <0>;label = "dummye2prom";address-width = <16>;num-addresses = <1>;reg = <0x51>;pagesize = <32>;size = <4096>;wp-gpios = <&gpio 4 0>; };};};};Code:
dtparam=i2c_arm=ondtoverlay=at24compatible-eepromCode:
pi@raspberrypi:~ $ ls /sys/bus/i2c/devices/1-0051driver dummye2prom5 eeprom modalias name of_node power subsystem supplier:platform:fe200000.gpio supplier:regulator:regulator.0 ueventpi@raspberrypi:~ $ sudo i2cdetect -y 1 0 1 2 3 4 5 6 7 8 9 a b c d e f00: -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 50: -- UU -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- -- pi@raspberrypi:~ $ i2cdetect -li2c-1i2c bcm2835 (i2c@7e804000) I2C adapteri2c-20i2c fef04500.i2c I2C adapteri2c-21i2c fef09500.i2c I2C adapterpi@raspberrypi:~ $ ls /sys/bus/i2c/driversat24 dummy stmpe-i2cpi@raspberrypi:~ $ ls /sys/bus/i2c/devices/1-0051driver dummye2prom5 eeprom modalias name of_node power subsystem supplier:platform:fe200000.gpio supplier:regulator:regulator.0 ueventCode:
pi@raspberrypi:~ $ sudo eepflash.sh --read --device=1 --address=0x51 -t=24c32 -f hat_eeprom_dump.eepThis will attempt to talk to an eeprom at i2c address 0x0x51. Make sure there is an eeprom at this address.This script comes with ABSOLUTELY no warranty. Continue only if you know what you are doing.Do you wish to continue? (yes/no): yes/usr/local/bin/eepflash.sh: 161: echo: echo: I/O errorReading...dd: failed to open '/sys/class/i2c-adapter/i2c-1/1-000x51/eeprom': No such file or directoryClosing EEPROM Device./usr/local/bin/eepflash.sh: 189: echo: echo: I/O errorError doing I/O operation.Code:
pi@raspberrypi:~ $ sudo dd if=/sys/class/i2c-dev/i2c-1/device/1-0051/eeprom bs=1 count=4096 | hexdump -C00000000 52 2d 50 69 02 00 01 00 46 00 00 00 01 00 00 00 |R-Pi....F.......|00000010 32 00 00 00 9c 6e 67 e6 4e 3c 6f 8e 79 47 e0 a8 |2....ng.N<o.yG..|00000020 01 d0 3a 83 00 00 03 00 0c 0e 52 61 73 70 62 65 |..:.......Raspbe|00000030 72 72 79 20 50 69 4d 2e 32 20 48 41 54 2b 20 4d |rry PiM.2 HAT+ M|00000040 20 4b 65 79 90 1a ff ff ff ff ff ff ff ff ff ff | Key............|00000050 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff |................|*00000fe0 30 30 30 30 31 31 32 34 30 30 31 30 31 34 31 34 |0000112400101414|00000ff0 00 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff |................|4096+0 records in4096+0 records out4096 bytes (4.1 kB, 4.0 KiB) copied, 2.1727 s, 1.9 kB/s00001000pi@raspberrypi:~ $ sudo dd if=/sys/class/i2c-dev/i2c-1/device/1-0051/eeprom bs=1 count=4096 | hexdump -C > hateeprom.eep4096+0 records in4096+0 records out4096 bytes (4.1 kB, 4.0 KiB) copied, 2.13714 s, 1.9 kB/sCode:
pi@raspberrypi:~ $ eepdump hateeprom.eep hat_eeprom_dump.txtWARNING: Format signature mismatchUnexpected EOF or error occurredStatistics: Posted by aBUGSworstnightmare — Sun May 26, 2024 7:41 am