Re: [PATCH V3 3/3] ARM: mmp: bring up pxa988 with device tree support

[Arnd Bergmann <arnd@arndb.de>]

On Tuesday 09 July 2013, Neil Zhang wrote:
> +	soc {
> +		compatible = "simple-bus";
> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +		interrupt-parent = <&gic>;
> +		ranges;
> +
> +		gic: interrupt-controller@d1dfe100 {
> +			compatible = "arm,cortex-a9-gic";
> +			#interrupt-cells = <3>;
> +			#address-cells = <1>;
> +			interrupt-controller;
> +			reg = <0xd1dff000 0x1000>,
> +			      <0xd1dfe100 0x0100>;
> +		};
> +
> +		L2: l2-cache-controller@d1dfb000 {
> +			compatible = "arm,pl310-cache";
> +			reg = <0xd1dfb000 0x1000>;
> +			arm,data-latency = <2 1 1>;
> +			arm,tag-latency = <2 1 1>;
> +			arm,pwr-dynamic-clk-gating;
> +			arm,pwr-standby-mode;
> +			cache-unified;
> +			cache-level = <2>;
> +		};
> +
> +		local-timer@d1dfe600 {
> +			compatible = "arm,cortex-a9-twd-timer";
> +			reg = <0xd1dfe600 0x20>;
> +			interrupts = <1 13 0x304>;
> +		};
> +
> +		axi@d4200000 {	/* AXI */
> +			compatible = "simple-bus";
> +			#address-cells = <1>;
> +			#size-cells = <1>;
> +			ranges = <0xd4200000 0xd4200000 0x00200000>;
> +
> +			intc: wakeupgen@d4282000 {
> +				compatible = "marvell,mmp-intc";
> +				reg = <0xd4282000 0x1000>;
> +				marvell,intc-wakeup = <0x114 0x3
> +						    0x144 0x3>;
> +			};
> +		};

I am guessing that the structure does not actually reflect the hardware.

Shouldn't AXI be the top-level bus, with the other stuff under it?

> +
> +
> +			uart1: uart@d4017000 {
> +				compatible = "marvell,mmp-uart";
> +				reg = <0xd4017000 0x1000>;
> +				interrupts = <0 27 0x4>;
> +				status = "disabled";
> +			};

The uart node should be called "serial@d4017000" instead of "uart@d4017000".

> diff --git a/arch/arm/mach-mmp/reset.c b/arch/arm/mach-mmp/reset.c
> new file mode 100644
> index 0000000..b90ec54
> --- /dev/null
> +++ b/arch/arm/mach-mmp/reset.c
> @@ -0,0 +1,66 @@
> +/*
> + * linux/arch/arm/mach-mmp/reset.c

I think this could just be part of the smp.c file.

> + *
> + * Author:	Neil Zhang <zhangwm@marvell.com>
> + * Copyright:	(C) 2012 Marvell International Ltd.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/smp.h>
> +
> +#include <asm/io.h>
> +#include <asm/cacheflush.h>
> +#include <asm/mach/map.h>
> +
> +#include <mach/addr-map.h>
> +
> +#include "reset.h"
> +
> +#define PMU_CC2_AP			APMU_REG(0x0100)
> +#define CIU_CA9_WARM_RESET_VECTOR	CIU_REG(0x00d8)

You should not hardcode the addresses here, better find them from the device tree.
> +
> +#define CPU_CORE_RST(n)	(1 << ((n) * 4 + 16))
> +#define CPU_DBG_RST(n)	(1 << ((n) * 4 + 18))
> +#define CPU_WDOG_RST(n)	(1 << ((n) * 4 + 19))

This should probably go into a reset controller driver, in drivers/reset/

	Arnd