Re: [Qemu-devel] [qemu PATCH 2/2] arm: add fw_cfg to "virt" board

[Peter Maydell]

On 27 November 2014 at 23:18, Laszlo Ersek <address@hidden> wrote:
> fw_cfg already supports exposure over MMIO (used in ppc/mac_newworld.c,
> ppc/mac_oldworld.c, sparc/sun4m.c); we can easily add it to the "virt"
> board.
>
> The mmio register block of fw_cfg is advertized in the device tree. As
> base address we pick 0x09020000, which conforms to the comment preceding
> "a15memmap": it falls in the miscellaneous device I/O range 128MB..256MB,
> and it is aligned at 64KB.

> +    nodename = g_strdup_printf("/address@hidden" PRIx64, base);
> +    qemu_fdt_add_subnode(vbi->fdt, nodename);
> +    qemu_fdt_setprop_string(vbi->fdt, nodename,
> +                            "compatible", "fw-cfg,mmio");
> +    qemu_fdt_setprop_sized_cells(vbi->fdt, nodename, "reg",
> +                                 2, base, 2, FW_CFG_SIZE,
> +                                 2, base + FW_CFG_SIZE, 2, FW_CFG_DATA_SIZE);
> +    g_free(nodename);

Are you planning to submit this DT binding to the kernel folks
as a proper official one (ie documented)? I know the kernel
doesn't need to read/write it, but the kernel doc tree is
AFAIK the only place that's actually documenting ARM DT
bindings right now...

thanks
-- PMM