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authorLinus Torvalds <torvalds@linux-foundation.org>2014-04-05 13:51:19 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-05 13:51:19 -0700
commitdfc25e4503aef6b82a1de4a0fbe19aafa8648fbe (patch)
tree0a4f3a07e2286918298e635186e42726f4658cbd /arch/arm/mach-bcm/board_bcm2835.c
parent9f800363bb0ea459e15bef0928a72c88d374e489 (diff)
parent8f881c67368f82d0e20e1072b50b21132cc2440d (diff)
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Merge tag 'cleanup-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC cleanups from Arnd Bergmann: "These cleanup patches are mainly move stuff around and should all be harmless. They are mainly split out so that other branches can be based on top to avoid conflicts. Notable changes are: - We finally remove all mach/timex.h, after CLOCK_TICK_RATE is no longer used (Uwe Kleine-König) - The Qualcomm MSM platform is split out into legacy mach-msm and new-style mach-qcom, to allow easier maintainance of the new hardware support without regressions (Kumar Gala) - A rework of some of the Kconfig logic to simplify multiplatform support (Rob Herring) - Samsung Exynos gets closer to supporting multiplatform (Sachin Kamat and others) - mach-bcm3528 gets merged into mach-bcm (Stephen Warren) - at91 gains some common clock framework support (Alexandre Belloni, Jean-Jacques Hiblot and other French people)" * tag 'cleanup-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (89 commits) ARM: hisi: select HAVE_ARM_SCU only for SMP ARM: efm32: allow uncompress debug output ARM: prima2: build reset code standalone ARM: at91: add PWM clock ARM: at91: move sam9261 SoC to common clk ARM: at91: prepare common clk transition for sam9261 SoC ARM: at91: updated the at91_dt_defconfig with support for the ADS7846 ARM: at91: dt: sam9261: Device Tree support for the at91sam9261ek ARM: at91: dt: defconfig: Added the sam9261 to the list of DT-enabled SOCs ARM: at91: dt: Add at91sam9261 dt SoC support ARM: at91: switch sam9rl to common clock framework ARM: at91/dt: define main clk frequency of at91sam9rlek ARM: at91/dt: define at91sam9rl clocks ARM: at91: prepare common clk transition for sam9rl SoCs ARM: at91: prepare sam9 dt boards transition to common clk ARM: at91: dt: sam9rl: Device Tree for the at91sam9rlek ARM: at91/defconfig: Add the sam9rl to the list of DT-enabled SOCs ARM: at91: Add at91sam9rl DT SoC support ARM: at91: prepare at91sam9rl DT transition ARM: at91/defconfig: refresh at91sam9260_9g20_defconfig ...
Diffstat (limited to 'arch/arm/mach-bcm/board_bcm2835.c')
-rw-r--r--arch/arm/mach-bcm/board_bcm2835.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/arm/mach-bcm/board_bcm2835.c b/arch/arm/mach-bcm/board_bcm2835.c
new file mode 100644
index 0000000..70f2f39
--- /dev/null
+++ b/arch/arm/mach-bcm/board_bcm2835.c
@@ -0,0 +1,137 @@
+/*
+ * 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.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/clk/bcm2835.h>
+
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+
+#define PM_RSTC 0x1c
+#define PM_RSTS 0x20
+#define PM_WDOG 0x24
+
+#define PM_PASSWORD 0x5a000000
+#define PM_RSTC_WRCFG_MASK 0x00000030
+#define PM_RSTC_WRCFG_FULL_RESET 0x00000020
+#define PM_RSTS_HADWRH_SET 0x00000040
+
+#define BCM2835_PERIPH_PHYS 0x20000000
+#define BCM2835_PERIPH_VIRT 0xf0000000
+#define BCM2835_PERIPH_SIZE SZ_16M
+
+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(enum reboot_mode 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);
+}
+
+/*
+ * We can't really power off, but if we do the normal reset scheme, and
+ * indicate to bootcode.bin not to reboot, then most of the chip will be
+ * powered off.
+ */
+static void bcm2835_power_off(void)
+{
+ u32 val;
+
+ /*
+ * We set the watchdog hard reset bit here to distinguish this reset
+ * from the normal (full) reset. bootcode.bin will not reboot after a
+ * hard reset.
+ */
+ val = readl_relaxed(wdt_regs + PM_RSTS);
+ val &= ~PM_RSTC_WRCFG_MASK;
+ val |= PM_PASSWORD | PM_RSTS_HADWRH_SET;
+ writel_relaxed(val, wdt_regs + PM_RSTS);
+
+ /* Continue with normal reset mechanism */
+ bcm2835_restart(REBOOT_HARD, "");
+}
+
+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();
+ if (wdt_regs)
+ pm_power_off = bcm2835_power_off;
+
+ 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 = irqchip_init,
+ .init_machine = bcm2835_init,
+ .restart = bcm2835_restart,
+ .dt_compat = bcm2835_compat
+MACHINE_END
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