Re: [PATCH v5 0/3] LoongArch: Add Loongson-2K BMC support

[Corey Minyard <corey@minyard.net>]

On Fri, Jun 20, 2025 at 10:06:26AM +0800, Binbin Zhou wrote:
> Hi all:
> 
> This patch set introduces the Loongson-2K BMC.
> 
> It is a PCIe device present on servers similar to the Loongson-3 CPUs.
> And it is a multifunctional device (MFD), such as display as a sub-function
> of it.
> 
> For IPMI, according to the existing design, we use software simulation to
> implement the KCS interface registers: Stauts/Command/Data_Out/Data_In.

The IPMI portions look good to me.  You will need acks from the MFD
maintainer and I can get it in through my tree, or I can give you:

For IPMI portions:
Acked-by: Corey Minyard <corey@minyard.net>

and it could go in through the MFD tree.

Thanks,

-corey

> 
> Also since both host side and BMC side read and write kcs status, we use
> fifo pointer to ensure data consistency.
> 
> For the display, based on simpledrm, the resolution is read from a fixed
> position in the BMC since the hardware does not support auto-detection
> of the resolution. Of course, we will try to support multiple
> resolutions later, through a vbios-like approach.
> 
> Especially, for the BMC reset function, since the display will be
> disconnected when BMC reset, we made a special treatment of re-push.
> 
> Based on this, I will present it in four patches:
> patch-1: BMC device PCI resource allocation.
> patch-2: BMC reset function support
> patch-3: IPMI implementation
> 
> Thanks.
> 
> -------
> V5:
> - Rebase on linux-ipmi/for-next branch.
> - Rebase on linux-mfd/for-mfd-next branch.
> Patch (1/3):
>  - Rename ls2kbmc-mfd.c to ls2k-bmc-core.c;
>  - Rename MFD_LS2K_BMC to MFD_LS2K_BMC_CORE and update its help text.
> Patch (3/3):
>  - Add an IPMI_LS2K config in the IPMI section that enables the IPMI
>    interface and selects MFD_LS2K_BMC_CORE.
> 
> Link to V4:
> https://lore.kernel.org/all/cover.1749731531.git.zhoubinbin@loongson.cn/
> 
> V4:
> - Add Reviewed-by tag;
> - Change the order of the patches.
> Patch (1/3):
>   - Fix build warning by lkp: Kconfig tristate -> bool
>     - https://lore.kernel.org/all/202505312022.QmFmGE1F-lkp@intel.com/
>  - Update commit message;
>  - Move MFD_LS2K_BMC after MFD_INTEL_M10_BMC_PMCI in Kconfig and
>    Makefile.
> Patch (2/3):
>   - Remove unnecessary newlines;
>   - Rename ls2k_bmc_check_pcie_connected() to
>     ls2k_bmc_pcie_is_connected();
>   - Update comment message.
> Patch (3/3):
>   - Remove unnecessary newlines.
> 
> Link to V3:
> https://lore.kernel.org/all/cover.1748505446.git.zhoubinbin@loongson.cn/
> 
> V3:
> Patch (1/3):
>  - Drop "MFD" in title and comment;
>  - Fromatting code;
>  - Add clearer comments.
> Patch (2/3):
>  - Rebase linux-ipmi/next tree;
>  - Use readx()/writex() to read and write IPMI data instead of structure
>    pointer references;
>  - CONFIG_LOONGARCH -> MFD_LS2K_BMC;
>  - Drop unused output.
> Patch (3/3):
>  - Inline the ls2k_bmc_gpio_reset_handler() function to ls2k_bmc_pdata_initial();
>  - Add clearer comments.
>  - Use proper multi-line commentary as per the Coding Style documentation;
>  - Define all magic numbers.
> 
> Link to V2:
> https://lore.kernel.org/all/cover.1747276047.git.zhoubinbin@loongson.cn/
> 
> V2:
> - Drop ls2kdrm, use simpledrm instead.
> Patch (1/3):
>  - Use DEFINE_RES_MEM_NAMED/MFD_CELL_RES simplified code;
>  - Add resolution fetching due to replacing the original display
>    solution with simpledrm; 
>  - Add aperture_remove_conflicting_devices() to avoid efifb
>    conflict with simpledrm.
> Patch (3/3):
>  - This part of the function, moved from the original ls2kdrm to mfd;
>  - Use set_console to implement the Re-push display function.
> 
> Link to V1:
> https://lore.kernel.org/all/cover.1735550269.git.zhoubinbin@loongson.cn/
> 
> Binbin Zhou (3):
>   mfd: ls2kbmc: Introduce Loongson-2K BMC core driver
>   mfd: ls2kbmc: Add Loongson-2K BMC reset function support
>   ipmi: Add Loongson-2K BMC support
> 
>  drivers/char/ipmi/Kconfig        |   7 +
>  drivers/char/ipmi/Makefile       |   1 +
>  drivers/char/ipmi/ipmi_si.h      |   7 +
>  drivers/char/ipmi/ipmi_si_intf.c |   4 +
>  drivers/char/ipmi/ipmi_si_ls2k.c | 189 ++++++++++++
>  drivers/mfd/Kconfig              |  11 +
>  drivers/mfd/Makefile             |   2 +
>  drivers/mfd/ls2k-bmc-core.c      | 485 +++++++++++++++++++++++++++++++
>  8 files changed, 706 insertions(+)
>  create mode 100644 drivers/char/ipmi/ipmi_si_ls2k.c
>  create mode 100644 drivers/mfd/ls2k-bmc-core.c
> 
> 
> base-commit: 8ffcb7560b4a15faf821df95e3ab532b2b020f8c
> -- 
> 2.47.1
>