[PATCH 2/8] ARM: MCS814x: add Device Tree based MCS8140 board support
Arnd Bergmann
arnd at arndb.de
Tue Jul 17 09:19:43 EDT 2012
On Sunday 15 July 2012, Florian Fainelli wrote:
> +
> + uart0: serial at 400dc000 {
> + compatible = "ns16550";
> + reg = <0x400dc000 0x20>;
> + clock-frequency = <50000000>;
> + reg-shift = <2>;
> + interrupts = <21>;
> + status = "okay";
> + };
We often mark stuff like the uart as status="disabled" in the .dtsi file
and only enable it in the board specific .dts file when it's actually
connected. For components that are always present and usable, that's
of course not necessary.
> +
> + adc {
> + compatible = "simple-bus";
> + #address-cells = <2>;
> + #size-cells = <1>;
> + // 8 64MB chip-selects
> + ranges = <0 0 0x00000000 0x4000000 // sdram
> + 1 0 0x04000000 0x4000000 // sdram
> + 2 0 0x08000000 0x4000000 // reserved
> + 3 0 0x0c000000 0x4000000 // flash/localbus
> + 4 0 0x10000000 0x4000000 // flash/localbus
> + 5 0 0x14000000 0x4000000 // flash/localbus
> + 6 0 0x18000000 0x4000000 // flash/localbus
> + 7 0 0x1c000000 0x4000000>; // flash/localbus
> +
> + sdram: memory at 0,0 {
> + reg = <0 0 0>;
> + };
> +
> + nor: flash at 7,0 {
> + reg = <7 0 0x4000000>;
> + compatible = "cfi-flash";
> + bank-width = <1>; // 8-bit external flash
> + #address-cells = <1>;
> + #size-cells = <1>;
> + };
> + };
Nice representation of the external buses. It does seem however that at
least the nor flash entry is board specific and should be moved into the
board .dts file.
I would probably do the same for the memory node, but that one is less
obvious as it seems that there is not much choice here.
> + usb0: ehci at 400fc000 {
> + compatible = "moschip,mcs814x-ehci", "usb-ehci";
> + reg = <0x400fc000 0x74>;
> + interrupts = <2>;
> + };
> +
> + usb1: ohci at 400fd000 {
> + compatible = "moschip,mcs814x-ohci", "ohci-le";
> + reg = <0x400fd000 0x74>;
> + interrupts = <11>;
> + };
> +
> + usb2: ohci at 400fe000 {
> + compatible = "moschip,mcs814x-ohci", "ohci-le";
> + reg = <0x400fe000 0x74>;
> + interrupts = <12>;
> + };
> +
> + usb3: otg at 400ff000 {
> + compatible = "moschip,msc814x-otg", "usb-otg";
> + reg = <0x400ff000 0x1000>;
> + interrupts = <13>;
> + };
same comment as for the uart, I would mark these as disabled and only
enable the ones that are connected on a give board.
> +
> +static void __init mcs814x_dt_device_init(void)
> +{
> + of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
> + mcs814x_init_machine();
> +}
> +
> +static const char *mcs8140_dt_board_compat[] __initdata = {
> + "moschip,mcs8140",
> + NULL, /* sentinel */
> +};
> +
> +DT_MACHINE_START(mcs8140_dt, "Moschip MCS8140 board")
> + /* Maintainer: Florian Fainelli <florian at openwrt.org> */
> + .timer = &mcs814x_timer,
> + .map_io = mcs814x_map_io,
> + .init_early = mcs814x_clk_init,
> + .init_irq = mcs814x_of_irq_init,
> + .init_machine = mcs814x_dt_device_init,
> + .restart = mcs814x_restart,
> + .dt_compat = mcs8140_dt_board_compat,
> +MACHINE_END
Not much to see here. Just move this into the common.c file. There is no
need to have a separate board file when all boards use the same one.
Arnd
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