diff options
Diffstat (limited to 'kernel/arch/arm/mach-imx/system.c')
| -rw-r--r-- | kernel/arch/arm/mach-imx/system.c | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-imx/system.c b/kernel/arch/arm/mach-imx/system.c new file mode 100644 index 000000000..51c35013b --- /dev/null +++ b/kernel/arch/arm/mach-imx/system.c @@ -0,0 +1,131 @@ +/* + * Copyright (C) 1999 ARM Limited + * Copyright (C) 2000 Deep Blue Solutions Ltd + * Copyright 2006-2007 Freescale Semiconductor, Inc. All Rights Reserved. + * Copyright 2008 Juergen Beisert, kernel@pengutronix.de + * Copyright 2009 Ilya Yanok, Emcraft Systems Ltd, yanok@emcraft.com + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/err.h> +#include <linux/delay.h> +#include <linux/of.h> +#include <linux/of_address.h> + +#include <asm/system_misc.h> +#include <asm/proc-fns.h> +#include <asm/mach-types.h> +#include <asm/hardware/cache-l2x0.h> + +#include "common.h" +#include "hardware.h" + +static void __iomem *wdog_base; +static struct clk *wdog_clk; + +/* + * Reset the system. It is called by machine_restart(). + */ +void mxc_restart(enum reboot_mode mode, const char *cmd) +{ + unsigned int wcr_enable; + + if (!wdog_base) + goto reset_fallback; + + if (!IS_ERR(wdog_clk)) + clk_enable(wdog_clk); + + if (cpu_is_mx1()) + wcr_enable = (1 << 0); + else + wcr_enable = (1 << 2); + + /* Assert SRS signal */ + __raw_writew(wcr_enable, wdog_base); + /* + * Due to imx6q errata ERR004346 (WDOG: WDOG SRS bit requires to be + * written twice), we add another two writes to ensure there must be at + * least two writes happen in the same one 32kHz clock period. We save + * the target check here, since the writes shouldn't be a huge burden + * for other platforms. + */ + __raw_writew(wcr_enable, wdog_base); + __raw_writew(wcr_enable, wdog_base); + + /* wait for reset to assert... */ + mdelay(500); + + pr_err("%s: Watchdog reset failed to assert reset\n", __func__); + + /* delay to allow the serial port to show the message */ + mdelay(50); + +reset_fallback: + /* we'll take a jump through zero as a poor second */ + soft_restart(0); +} + +void __init mxc_arch_reset_init(void __iomem *base) +{ + wdog_base = base; + + wdog_clk = clk_get_sys("imx2-wdt.0", NULL); + if (IS_ERR(wdog_clk)) + pr_warn("%s: failed to get wdog clock\n", __func__); + else + clk_prepare(wdog_clk); +} + +#ifdef CONFIG_CACHE_L2X0 +void __init imx_init_l2cache(void) +{ + void __iomem *l2x0_base; + struct device_node *np; + unsigned int val; + + np = of_find_compatible_node(NULL, NULL, "arm,pl310-cache"); + if (!np) + goto out; + + l2x0_base = of_iomap(np, 0); + if (!l2x0_base) { + of_node_put(np); + goto out; + } + + /* Configure the L2 PREFETCH and POWER registers */ + val = readl_relaxed(l2x0_base + L310_PREFETCH_CTRL); + val |= 0x70800000; + /* + * The L2 cache controller(PL310) version on the i.MX6D/Q is r3p1-50rel0 + * The L2 cache controller(PL310) version on the i.MX6DL/SOLO/SL is r3p2 + * But according to ARM PL310 errata: 752271 + * ID: 752271: Double linefill feature can cause data corruption + * Fault Status: Present in: r3p0, r3p1, r3p1-50rel0. Fixed in r3p2 + * Workaround: The only workaround to this erratum is to disable the + * double linefill feature. This is the default behavior. + */ + if (cpu_is_imx6q()) + val &= ~(1 << 30 | 1 << 23); + writel_relaxed(val, l2x0_base + L310_PREFETCH_CTRL); + + iounmap(l2x0_base); + of_node_put(np); + +out: + l2x0_of_init(0, ~0); +} +#endif |