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-rw-r--r--arch/arm/mach-bcm2835/bcm2835.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/arch/arm/mach-bcm2835/bcm2835.c b/arch/arm/mach-bcm2835/bcm2835.c
new file mode 100644
index 00000000000..f0d739f4b7a
--- /dev/null
+++ b/arch/arm/mach-bcm2835/bcm2835.c
@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2010 Broadcom
+ *
+ * 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/delay.h>
+#include <linux/init.h>
+#include <linux/irqchip/bcm2835.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/bcm2835_timer.h>
+#include <linux/clk/bcm2835.h>
+
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+
+#include <mach/bcm2835_soc.h>
+
+#define PM_RSTC 0x1c
+#define PM_WDOG 0x24
+
+#define PM_PASSWORD 0x5a000000
+#define PM_RSTC_WRCFG_MASK 0x00000030
+#define PM_RSTC_WRCFG_FULL_RESET 0x00000020
+
+static void __iomem *wdt_regs;
+
+/*
+ * The machine restart method can be called from an atomic context so we won't
+ * be able to ioremap the regs then.
+ */
+static void bcm2835_setup_restart(void)
+{
+ struct device_node *np = of_find_compatible_node(NULL, NULL,
+ "brcm,bcm2835-pm-wdt");
+ if (WARN(!np, "unable to setup watchdog restart"))
+ return;
+
+ wdt_regs = of_iomap(np, 0);
+ WARN(!wdt_regs, "failed to remap watchdog regs");
+}
+
+static void bcm2835_restart(char mode, const char *cmd)
+{
+ u32 val;
+
+ if (!wdt_regs)
+ return;
+
+ /* use a timeout of 10 ticks (~150us) */
+ writel_relaxed(10 | PM_PASSWORD, wdt_regs + PM_WDOG);
+ val = readl_relaxed(wdt_regs + PM_RSTC);
+ val &= ~PM_RSTC_WRCFG_MASK;
+ val |= PM_PASSWORD | PM_RSTC_WRCFG_FULL_RESET;
+ writel_relaxed(val, wdt_regs + PM_RSTC);
+
+ /* No sleeping, possibly atomic. */
+ mdelay(1);
+}
+
+static struct map_desc io_map __initdata = {
+ .virtual = BCM2835_PERIPH_VIRT,
+ .pfn = __phys_to_pfn(BCM2835_PERIPH_PHYS),
+ .length = BCM2835_PERIPH_SIZE,
+ .type = MT_DEVICE
+};
+
+static void __init bcm2835_map_io(void)
+{
+ iotable_init(&io_map, 1);
+}
+
+static void __init bcm2835_init(void)
+{
+ int ret;
+
+ bcm2835_setup_restart();
+ bcm2835_init_clocks();
+
+ ret = of_platform_populate(NULL, of_default_bus_match_table, NULL,
+ NULL);
+ if (ret) {
+ pr_err("of_platform_populate failed: %d\n", ret);
+ BUG();
+ }
+}
+
+static const char * const bcm2835_compat[] = {
+ "brcm,bcm2835",
+ NULL
+};
+
+DT_MACHINE_START(BCM2835, "BCM2835")
+ .map_io = bcm2835_map_io,
+ .init_irq = bcm2835_init_irq,
+ .handle_irq = bcm2835_handle_irq,
+ .init_machine = bcm2835_init,
+ .timer = &bcm2835_timer,
+ .restart = bcm2835_restart,
+ .dt_compat = bcm2835_compat
+MACHINE_END