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-rw-r--r--kernel/arch/arm/mach-imx/system.c131
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