Question about IPMI OEM command to expose PCIe slot-i2c mapping.

[Jaghathiswari Rankappagounder Natarajan]

Hello,

BMC has information in the device tree about which I2C bus goes to which
PCIe slot. I would like the host to get this information from the BMC
firmware by sending a IPMI OEM command.

How I want to do this:
(for example in arch/arm/boot/dts/aspeed-bmc-quanta-q71l.dts file, I
want to add an extra attribute "slot" for each I2C bus, which
indicates which i2c bus goes to which PCIe slot )
&i2c2 {
status = "okay";

/* 0: PCIe Slot 2,
*    Slot 3,
*    Slot 6,
*    Slot 7
*/i2c-switch at 74 <https://lists.ozlabs.org/listinfo/openbmc> {
compatible = "nxp,pca9546";
reg = <0x74>;
#address-cells = <1>;
#size-cells = <0>;
i2c-mux-idle-disconnect;  /* may use mux at 77
<https://lists.ozlabs.org/listinfo/openbmc> next. */

i2c_pcie2: i2c at 0 <https://lists.ozlabs.org/listinfo/openbmc> {
#address-cells = <1>;
#size-cells = <0>;
reg = <0>;

----->slot = "PE2";<-----

};

i2c_pcie3: i2c at 1 <https://lists.ozlabs.org/listinfo/openbmc> {
#address-cells = <1>; #size-cells = <0>; reg = <1>;

----->slot = "PE2";<-----

}; } Whenever the host sends the IPMI OEM command to get the I2C bus/PCIe
slot mapping info, the BMC can parse through all the i2c devices under
/sys/bus/i2c/ and find all the i2c devices which have a property called
slot under of_node. The BMC firmware can then send the I2C bus number and
the slot name for all the i2c devices found above, as part of the IPMI
command response. Does anyone have any ideas/suggestions about this ?
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