linux-kernel - RE: [PATCH v12 1/1] Add support for IPMB driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <VI1PR05MB62398E3DADCD067A23BBC53BDAED0@VI1PR05MB6239.eurprd05.prod.outlook.com>
Date:   Tue, 11 Jun 2019 13:28:29 +0000
From:   Asmaa Mnebhi <Asmaa@...lanox.com>
To:     Randy Dunlap <rdunlap@...radead.org>,
        "minyard@....org" <minyard@....org>,
        "wsa@...-dreams.de" <wsa@...-dreams.de>,
        Vadim Pasternak <vadimp@...lanox.com>,
        Michael Shych <michaelsh@...lanox.com>
CC:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-i2c@...r.kernel.org" <linux-i2c@...r.kernel.org>
Subject: RE: [PATCH v12 1/1] Add support for IPMB driver

Hello Randy,

Please refer to the slave-interface linux documentation:
https://www.kernel.org/doc/Documentation/i2c/slave-interface

Thanks.
Asmaa

-----Original Message-----
From: Randy Dunlap <rdunlap@...radead.org> 
Sent: Monday, June 10, 2019 5:56 PM
To: Asmaa Mnebhi <Asmaa@...lanox.com>; minyard@....org; wsa@...-dreams.de; Vadim Pasternak <vadimp@...lanox.com>; Michael Shych <michaelsh@...lanox.com>
Cc: linux-kernel@...r.kernel.org; linux-i2c@...r.kernel.org
Subject: Re: [PATCH v12 1/1] Add support for IPMB driver

On 6/10/19 11:57 AM, Asmaa Mnebhi wrote:
> Support receiving IPMB requests on a Satellite MC from the BMC.
> Once a response is ready, this driver will send back a response to the 
> BMC via the IPMB channel.
> 
> Signed-off-by: Asmaa Mnebhi <Asmaa@...lanox.com>
> Acked-by: vadimp@...lanox.com
> ---
>  Documentation/IPMB.txt           | 103 +++++++++++
>  drivers/char/ipmi/Kconfig        |   8 +
>  drivers/char/ipmi/Makefile       |   1 +
>  drivers/char/ipmi/ipmb_dev_int.c | 364 
> +++++++++++++++++++++++++++++++++++++++
>  4 files changed, 476 insertions(+)
>  create mode 100644 Documentation/IPMB.txt  create mode 100644 
> drivers/char/ipmi/ipmb_dev_int.c
> 
> diff --git a/Documentation/IPMB.txt b/Documentation/IPMB.txt new file 
> mode 100644 index 0000000..7160d53
> --- /dev/null
> +++ b/Documentation/IPMB.txt
> @@ -0,0 +1,103 @@

[...]

> +Instantiate the device
> +----------------------
> +
> +After loading the driver, you can instantiate the device as described 
> +in 'Documentation/i2c/instantiating-devices'.
> +If you have multiple BMCs, each connected to your Satellite MC via a 
> +different I2C bus, you can instantiate a device for each of those 
> +BMCs.
> +The name of the instantiated device contains the I2C bus number 
> +associated with it as follows:
> +
> +BMC1 ------ IPMB/I2C bus 1 ---------|   /dev/ipmb-1
> +				Satellite MC
> +BMC1 ------ IPMB/I2C bus 2 ---------|   /dev/ipmb-2
> +
> +For instance, you can instantiate the ipmb-dev-int device from user 
> +space at the 7 bit address 0x10 on bus 2:
> +
> +  # echo ipmb-dev 0x1010 > /sys/bus/i2c/devices/i2c-2/new_device

This is confusing.

Can you clarify how the 7-bit address is extracted from that hex number?
Is the 7-bit address repeated (duplicated)?
Is the 7-bit address the low order (low bits) 0x10 or the 0x10 at bits
15-8 (or 14-8)?

> +This will create the device file /dev/ipmb-2, which can be accessed 
> +by the user space program. The device needs to be instantiated before 
> +running the user space program.

thanks.
--
~Randy