On 11/6/07, Marian Balakowicz <[EMAIL PROTECTED]> wrote:
> This patch adds support for 'mpc5200-simple-platform' compatible
> boards which do not need a platform specific setup. Such boards
> are supported assuming the following:
>
> - GPIO pins are configured by the firmware,
> - CDM configuration (clocking) is setup correctly by firmware,
> - if the 'fsl,has-wdt' property is present in one of the
> gpt nodes, then it is safe to use such gpt to reset the board,
> - PCI is supported if enabled in the kernel configuration
>
> Signed-off-by: Marian Balakowicz <[EMAIL PROTECTED]>
> ---
>
> arch/powerpc/boot/dts/lite5200.dts | 2 -
> arch/powerpc/boot/dts/lite5200b.dts | 2 -
> arch/powerpc/platforms/52xx/Kconfig | 18 ++++++-
> arch/powerpc/platforms/52xx/Makefile | 1
> arch/powerpc/platforms/52xx/mpc5200_simple.c | 72
> ++++++++++++++++++++++++++
> 5 files changed, 91 insertions(+), 4 deletions(-)
> create mode 100644 arch/powerpc/platforms/52xx/mpc5200_simple.c
>
>
> diff --git a/arch/powerpc/boot/dts/lite5200.dts
> b/arch/powerpc/boot/dts/lite5200.dts
> index 6731763..5902362 100644
> --- a/arch/powerpc/boot/dts/lite5200.dts
> +++ b/arch/powerpc/boot/dts/lite5200.dts
> @@ -19,7 +19,7 @@
> / {
> model = "fsl,lite5200";
> // revision = "1.0";
> - compatible = "fsl,lite5200","generic-mpc5200";
> + compatible = "fsl,lite5200";
> #address-cells = <1>;
> #size-cells = <1>;
>
> diff --git a/arch/powerpc/boot/dts/lite5200b.dts
> b/arch/powerpc/boot/dts/lite5200b.dts
> index b540388..b509129 100644
> --- a/arch/powerpc/boot/dts/lite5200b.dts
> +++ b/arch/powerpc/boot/dts/lite5200b.dts
> @@ -19,7 +19,7 @@
> / {
> model = "fsl,lite5200b";
> // revision = "1.0";
> - compatible = "fsl,lite5200b","generic-mpc5200";
> + compatible = "fsl,lite5200b";
> #address-cells = <1>;
> #size-cells = <1>;
>
> diff --git a/arch/powerpc/platforms/52xx/Kconfig
> b/arch/powerpc/platforms/52xx/Kconfig
> index 2938d49..b8a6ebc 100644
> --- a/arch/powerpc/platforms/52xx/Kconfig
> +++ b/arch/powerpc/platforms/52xx/Kconfig
> @@ -19,6 +19,22 @@ config PPC_MPC5200_BUGFIX
>
> It is safe to say 'Y' here
>
> +config PPC_MPC5200_SIMPLE
> + bool "Generic support for simple MPC5200 based boards"
> + depends on PPC_MULTIPLATFORM && PPC32
> + select PPC_MPC5200
> + default n
> + help
> + This option enables support for a simple MPC52xx based boards which
> + do not need a custom platform specific setup. Such boards are
> + supported assuming the following:
> +
> + - GPIO pins are configured by the firmware,
> + - CDM configuration (clocking) is setup correctly by firmware,
> + - if the 'fsl,has-wdt' property is present in one of the
> + gpt nodes, then it is safe to use such gpt to reset the board,
> + - PCI is supported if enabled in the kernel configuration
... and there is a PCI bus node in the device tree.
I'd also add a list of the known boards that behave like this.
> +/*
> + * Called very early, MMU is off, device-tree isn't unflattened
> + */
> +static int __init mpc5200_simple_probe(void)
> +{
> + unsigned long node = of_get_flat_dt_root();
> +
> + if (!of_flat_dt_is_compatible(node, "mpc5200-simple-platform"))
> + return 0;
> + return 1;
> +}
I've thought some more about this, and I no longer think that this is
the best approach. I think having the mpc5200 simple platform is a
good thing, but I don't think we should have the device tree claim
compatibility with "mpc5200-simple-platform"
Trying to define exactly what "mpc5200-simple-platform" describes here
and now is probably over ambitious and there is the tendency to want
it change it's meaning over time. (just like with the compatible
field in device nodes; better to stick with real devices and not start
making stuff up).
Instead, I think we should drop "mpc5200-simple-platform" from the
device trees themselves and instead make mpc5200_simple_platform()
loop over a list of known boards that work with the simple 5200
platform.
In other words; make the assumption that it is easier to change the
kernel than it is to change the device tree.
So, do something like this:
static int __init mpc5200_simple_probe(void)
{
const char *board[] = { "promess,motionpro", "schindler,cm5200",
"tqc,tqm5200",
NULL };
int i = 0;
while (board[i]) {
if (of_flat_dt_is_compatible(node, board[i]))
break;
i++;
}
return (board[i] != NULL);
}
Cheers,
g.
--
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
[EMAIL PROTECTED]
(403) 399-0195
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