On Sun, Jul 10, 2016 at 09:12:03PM +0200, Mark Kettenis wrote:
> Currently the armv7 port has several bits ehci(4) glue code.
> Basically there is one of these for every SoC platform that we
> support. I converted the glue for the i.MX6 platform to use the FDT
> and that works fine. However, this prevents us from converting the
> other bits of glue, since it isn't possible to have multiple bits of
> glue for:
>
> ehic? at fdt?
>
> We have a couple of solutions here:
>
> 1. Introduce a single armv7 ehci(4) glue driver that calls the
> appropriate SoC-specifuc implementation based on the compatible
> string. With this approach we continue to have:
>
> ehci0 at simplebus1
>
> lines in dmesg.
>
> 2. Introduce SoC-specific busses such that we can have bus-specific
> glue code for each SoC platform we want to support. This would
> mean that on i.MX6 we would get something like:
>
> ehci0 at aipsbus1
>
> lines in dmesg. The SoC-specific bus drivers would be essentially
> clones of simplebus(4), with stricter match code that returns a
> higher value. Tis is not entirely straigtforward, and if we need
> to attach ehci(4) to mainbus(4) on more than one SoC the approach
> fails.
>
> 3. Use SoC-specific driver names. We'd get something like:
>
> imxehci0 at simplebus1
>
> on i.NX6 and
>
> omehci0 at simplebus0
>
> on OMAP. We'd need to think about how we document these new
> drivers.
>
> I'm currently leaning towards option #3. It can be argues that the
> SoC-specific glue code is complicated enough to warrant its own driver
> anyway. The changes are fairly easy to make and the code stays nicely
> separated. See diff below.
>
> Or is there another option that I'm missing?
#3 sounds good to me as well. The same problem occurs for ahci
as imx and sunxi both have it.
>
>
> Index: arch/armv7/conf/GENERIC
> ===================================================================
> RCS file: /cvs/src/sys/arch/armv7/conf/GENERIC,v
> retrieving revision 1.28
> diff -u -p -r1.28 GENERIC
> --- arch/armv7/conf/GENERIC 9 Jul 2016 12:32:50 -0000 1.28
> +++ arch/armv7/conf/GENERIC 10 Jul 2016 19:09:31 -0000
> @@ -52,8 +52,8 @@ iic* at imxiic?
> imxesdhc* at fdt? # SDHC controller
> sdmmc* at imxesdhc? # SD/MMC bus
> ahci* at fdt? # AHCI/SATA
> -ehci* at fdt? # EHCI (shim)
> -usb* at ehci?
> +imxehci* at fdt? # EHCI
> +usb* at imxehci?
>
> # OMAP3xxx/OMAP4xxx SoC
> omap0 at mainbus?
> Index: arch/armv7/imx/files.imx
> ===================================================================
> RCS file: /cvs/src/sys/arch/armv7/imx/files.imx,v
> retrieving revision 1.12
> diff -u -p -r1.12 files.imx
> --- arch/armv7/imx/files.imx 9 Jul 2016 12:32:50 -0000 1.12
> +++ arch/armv7/imx/files.imx 10 Jul 2016 19:09:31 -0000
> @@ -40,7 +40,8 @@ device fec: ether, ifnet, mii, ifmedia
> attach fec at fdt
> file arch/armv7/imx/if_fec.c fec
>
> -attach ehci at fdt with imxehci
> +device imxehci: usbus
> +attach imxehci at fdt
> file arch/armv7/imx/imxehci.c imxehci
>
> device imxesdhc: sdmmcbus
> Index: arch/armv7/imx/imxehci.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/armv7/imx/imxehci.c,v
> retrieving revision 1.11
> diff -u -p -r1.11 imxehci.c
> --- arch/armv7/imx/imxehci.c 10 Jul 2016 11:46:28 -0000 1.11
> +++ arch/armv7/imx/imxehci.c 10 Jul 2016 19:09:31 -0000
> @@ -94,6 +94,10 @@ struct cfattach imxehci_ca = {
> imxehci_detach
> };
>
> +struct cfdriver imxehci_cd = {
> + NULL, "imxehci", DV_DULL
> +};
> +
> int
> imxehci_match(struct device *parent, void *match, void *aux)
> {
>
