From mboxrd@z Thu Jan  1 00:00:00 1970
From: andrew@lunn.ch (Andrew Lunn)
Date: Wed, 27 Jun 2012 17:36:52 +0200
Subject: [PATCH v5 3/9] arm: mach-mvebu: add source files
In-Reply-To: <1340805290-9051-4-git-send-email-gregory.clement@free-electrons.com>
References: <1340805290-9051-1-git-send-email-gregory.clement@free-electrons.com>
 <1340805290-9051-4-git-send-email-gregory.clement@free-electrons.com>
Message-ID: <20120627153652.GE29702@lunn.ch>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

> diff --git a/arch/arm/mach-mvebu/system-controller.c b/arch/arm/mach-mvebu/system-controller.c
> new file mode 100644
> index 0000000..14331ba
> --- /dev/null
> +++ b/arch/arm/mach-mvebu/system-controller.c
> @@ -0,0 +1,100 @@
> +/*
> + * System controller support for Armada 370 and XP platforms.
> + *
> + * Copyright (C) 2012 Marvell
> + *
> + * Lior Amsalem <alior@marvell.com>
> + * Gregory CLEMENT <gregory.clement@free-electrons.com>
> + * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> + *
> + * This file is licensed under the terms of the GNU General Public
> + * License version 2.  This program is licensed "as is" without any
> + * warranty of any kind, whether express or implied.
> + *
> + * The Armada 370 and Armada XP SoCs both have a range of
> + * miscellaneous registers, that do not belong to a particular device,
> + * but rather provide system-level features. This basic
> + * system-controller driver provides a device tree binding for those
> + * registers, and implements utility functions offering various
> + * features related to those registers.
> + *
> + * For now, the feature set is limited to restarting the platform by a
> + * soft-reset, but it might be extended in the future.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/init.h>
> +#include <linux/of_address.h>
> +#include <linux/io.h>
> +
> +static void __iomem *system_controller_base;
> +
> +struct mvebu_system_controller {
> +	u32 rstoutn_mask_offset;
> +	u32 system_soft_reset_offset;
> +
> +	u32 rstoutn_mask_reset_out_en;
> +	u32 system_soft_reset;
> +};
> +static struct mvebu_system_controller *mvebu_sc;
> +
> +const struct mvebu_system_controller armada_370_xp_system_controller = {
> +	.rstoutn_mask_offset = 0x60,
> +	.system_soft_reset_offset = 0x64,
> +	.rstoutn_mask_reset_out_en = 0x1,
> +	.system_soft_reset = 0x1,
> +};
> +
> +const struct mvebu_system_controller orion_system_controller = {
> +	.rstoutn_mask_offset = 0x108,
> +	.system_soft_reset_offset = 0x10c,
> +	.rstoutn_mask_reset_out_en = 0x4,
> +	.system_soft_reset = 0x1,
> +};
> +
> +static struct of_device_id of_system_controller_table[] = {
> +	{.compatible = "marvell,orion-system-controller",
> +	 .data = (void *) &orion_system_controller},
> +	{.compatible = "marvell,armada-370-xp-system-controller",
> +	 .data = (void *) &armada_370_xp_system_controller},
> +	{ /* end of list */ },
> +};
> +
> +void mvebu_restart(char mode, const char *cmd)
> +{
> +	if (!system_controller_base) {
> +		pr_warn("Cannot restart, system-controller not available\n");

Does pr_warn() get shown by default? I would of probably gone for
BUG_ON() or WARN_ON(), to make it clearer what has happened. It may
not be a kernel bug, but a DT description bug, but it still a bug...

> +	} else {
> +		/*
> +		 * Enable soft reset to assert RSTOUTn.
> +		 */
> +		writel(mvebu_sc->rstoutn_mask_reset_out_en,
> +			system_controller_base +
> +			mvebu_sc->rstoutn_mask_offset);
> +		/*
> +		 * Assert soft reset.
> +		 */
> +		writel(mvebu_sc->system_soft_reset,
> +			system_controller_base +
> +			mvebu_sc->system_soft_reset_offset);
> +	}
> +	while (1)
> +		;
> +}

I tested this on a Kirkwood QNAP with DT property:

                system-controller at 20000 {
                        compatible = "marvell,orion-system-controller";
                        reg = <0x20000 0x1000>;
                };

and it works. So:

Tested-by: Andrew Lunn <andrew@lunn.ch>

However Orion5x has a slightly different variant, so i would like to
test it on that SoC as well. However, we don't have DT on Orion5x yet,
so i need to simulate it.

   Andrew