[U-Boot] [PATCH v4 0/8] x86: qemu: add fw_cfg interface support for qemu-x86 targets

[Bin Meng]

Hi Miao,

On Thu, Dec 31, 2015 at 10:55 AM, Miao Yan <yanmiaobest at gmail.com> wrote:
> The fw_cfg interface provided by QEMU allow guests to retrieve various information
> about the system, e.g. cpu number, variaous firmware data, kernel setup, etc. The
> fw_cfg interface can be accessed through 3 IO ports (on x86), using x86 in/out
> instructions.
>
>   - 0x510: select configuration items to access
>   - 0x511: reading this port will return data selected in 0x510
>   - 0x514: this can be used to detect if DMA interface is available
>
> If fw_cfg DMA interface is available, it can be used to accelerate
> accesses.
>
> This patchset adds the following supports for qemu-x86 targets:
>
>   + the fw_cfg driver itself
>
>   + add a U-Boot command 'fw' to support direct accessing kernel informtion
>     from fw_cfg interface, this saves the time of loading them from hard disk or
>     network again, through emulated devices.
>
>   + use fw_cfg to get cpu number at runtime, so smp boot no longer relies on
>     the cpu node hard-coded in dts files.
>
> Changes in v4:
>   - drop [PATCH v3 7/8] and limit maximum supported cpu number
>   - chance 'fw load' to take second parameter for initrd load address
>   - change default initrd load address for qemu-x86
>
> Miao Yan (8):
>   x86: qemu: add fw_cfg support
>   x86: qemu: add a cpu uclass driver for qemu target
>   x86: fix a typo in function name
>   x86: use actual CPU number for allocating memory
>   x86: qemu: add qemu_fwcfg_fdt_fixup()
>   x86: qemu: fix up cpu node in device tree
>   x86: qemu: adjust ramdisk load address
>   x86: qemu: add documentaion for the fw_cfg interface
>
>  arch/x86/cpu/mp_init.c           |  12 +-
>  arch/x86/cpu/qemu/Makefile       |   2 +-
>  arch/x86/cpu/qemu/cpu.c          |  57 +++++++
>  arch/x86/cpu/qemu/fw_cfg.c       | 333 +++++++++++++++++++++++++++++++++++++++
>  arch/x86/cpu/qemu/fw_cfg.h       | 108 +++++++++++++
>  arch/x86/cpu/qemu/qemu.c         |   7 +
>  arch/x86/dts/qemu-x86_i440fx.dts |  19 +--
>  arch/x86/dts/qemu-x86_q35.dts    |  19 +--
>  doc/README.x86                   |  35 +++-
>  include/configs/qemu-x86.h       |  13 ++
>  10 files changed, 559 insertions(+), 46 deletions(-)
>  create mode 100644 arch/x86/cpu/qemu/cpu.c
>  create mode 100644 arch/x86/cpu/qemu/fw_cfg.c
>  create mode 100644 arch/x86/cpu/qemu/fw_cfg.h
>
> --

Please add those git tags (eg: Reviewed-by, Tested-By, Acked-by) when
you rework your patch series. This helps future reviews of the same
patch series.

Regards,
Bin