Initial import

1 files changed, 203 insertions, 0 deletions

diff --git a/arch/arm/mach-tegra/platsmp.c b/arch/arm/mach-tegra/platsmp.c
new file mode 100644
index 000000000..b45086666
--- /dev/null
+++ b/arch/arm/mach-tegra/platsmp.c
@@ -0,0 +1,203 @@
+/*
+ *  linux/arch/arm/mach-tegra/platsmp.c
+ *
+ *  Copyright (C) 2002 ARM Ltd.
+ *  All Rights Reserved
+ *
+ *  Copyright (C) 2009 Palm
+ *  All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk/tegra.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/smp.h>
+
+#include <soc/tegra/fuse.h>
+#include <soc/tegra/pmc.h>
+
+#include <asm/cacheflush.h>
+#include <asm/mach-types.h>
+#include <asm/smp_plat.h>
+#include <asm/smp_scu.h>
+
+#include "common.h"
+#include "flowctrl.h"
+#include "iomap.h"
+#include "reset.h"
+
+static cpumask_t tegra_cpu_init_mask;
+
+static void tegra_secondary_init(unsigned int cpu)
+{
+	cpumask_set_cpu(cpu, &tegra_cpu_init_mask);
+}
+
+
+static int tegra20_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	cpu = cpu_logical_map(cpu);
+
+	/*
+	 * Force the CPU into reset. The CPU must remain in reset when
+	 * the flow controller state is cleared (which will cause the
+	 * flow controller to stop driving reset if the CPU has been
+	 * power-gated via the flow controller). This will have no
+	 * effect on first boot of the CPU since it should already be
+	 * in reset.
+	 */
+	tegra_put_cpu_in_reset(cpu);
+
+	/*
+	 * Unhalt the CPU. If the flow controller was used to
+	 * power-gate the CPU this will cause the flow controller to
+	 * stop driving reset. The CPU will remain in reset because the
+	 * clock and reset block is now driving reset.
+	 */
+	flowctrl_write_cpu_halt(cpu, 0);
+
+	tegra_enable_cpu_clock(cpu);
+	flowctrl_write_cpu_csr(cpu, 0); /* Clear flow controller CSR. */
+	tegra_cpu_out_of_reset(cpu);
+	return 0;
+}
+
+static int tegra30_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	int ret;
+	unsigned long timeout;
+
+	cpu = cpu_logical_map(cpu);
+	tegra_put_cpu_in_reset(cpu);
+	flowctrl_write_cpu_halt(cpu, 0);
+
+	/*
+	 * The power up sequence of cold boot CPU and warm boot CPU
+	 * was different.
+	 *
+	 * For warm boot CPU that was resumed from CPU hotplug, the
+	 * power will be resumed automatically after un-halting the
+	 * flow controller of the warm boot CPU. We need to wait for
+	 * the confirmaiton that the CPU is powered then removing
+	 * the IO clamps.
+	 * For cold boot CPU, do not wait. After the cold boot CPU be
+	 * booted, it will run to tegra_secondary_init() and set
+	 * tegra_cpu_init_mask which influences what tegra30_boot_secondary()
+	 * next time around.
+	 */
+	if (cpumask_test_cpu(cpu, &tegra_cpu_init_mask)) {
+		timeout = jiffies + msecs_to_jiffies(50);
+		do {
+			if (tegra_pmc_cpu_is_powered(cpu))
+				goto remove_clamps;
+			udelay(10);
+		} while (time_before(jiffies, timeout));
+	}
+
+	/*
+	 * The power status of the cold boot CPU is power gated as
+	 * default. To power up the cold boot CPU, the power should
+	 * be un-gated by un-toggling the power gate register
+	 * manually.
+	 */
+	if (!tegra_pmc_cpu_is_powered(cpu)) {
+		ret = tegra_pmc_cpu_power_on(cpu);
+		if (ret)
+			return ret;
+
+		/* Wait for the power to come up. */
+		timeout = jiffies + msecs_to_jiffies(100);
+		while (!tegra_pmc_cpu_is_powered(cpu)) {
+			if (time_after(jiffies, timeout))
+				return -ETIMEDOUT;
+			udelay(10);
+		}
+	}
+
+remove_clamps:
+	/* CPU partition is powered. Enable the CPU clock. */
+	tegra_enable_cpu_clock(cpu);
+	udelay(10);
+
+	/* Remove I/O clamps. */
+	ret = tegra_pmc_cpu_remove_clamping(cpu);
+	if (ret)
+		return ret;
+
+	udelay(10);
+
+	flowctrl_write_cpu_csr(cpu, 0); /* Clear flow controller CSR. */
+	tegra_cpu_out_of_reset(cpu);
+	return 0;
+}
+
+static int tegra114_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	int ret = 0;
+
+	cpu = cpu_logical_map(cpu);
+
+	if (cpumask_test_cpu(cpu, &tegra_cpu_init_mask)) {
+		/*
+		 * Warm boot flow
+		 * The flow controller in charge of the power state and
+		 * control for each CPU.
+		 */
+		/* set SCLK as event trigger for flow controller */
+		flowctrl_write_cpu_csr(cpu, 1);
+		flowctrl_write_cpu_halt(cpu,
+				FLOW_CTRL_WAITEVENT | FLOW_CTRL_SCLK_RESUME);
+	} else {
+		/*
+		 * Cold boot flow
+		 * The CPU is powered up by toggling PMC directly. It will
+		 * also initial power state in flow controller. After that,
+		 * the CPU's power state is maintained by flow controller.
+		 */
+		ret = tegra_pmc_cpu_power_on(cpu);
+	}
+
+	return ret;
+}
+
+static int tegra_boot_secondary(unsigned int cpu,
+					  struct task_struct *idle)
+{
+	if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC) && tegra_get_chip_id() == TEGRA20)
+		return tegra20_boot_secondary(cpu, idle);
+	if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC) && tegra_get_chip_id() == TEGRA30)
+		return tegra30_boot_secondary(cpu, idle);
+	if (IS_ENABLED(CONFIG_ARCH_TEGRA_114_SOC) && tegra_get_chip_id() == TEGRA114)
+		return tegra114_boot_secondary(cpu, idle);
+	if (IS_ENABLED(CONFIG_ARCH_TEGRA_124_SOC) && tegra_get_chip_id() == TEGRA124)
+		return tegra114_boot_secondary(cpu, idle);
+
+	return -EINVAL;
+}
+
+static void __init tegra_smp_prepare_cpus(unsigned int max_cpus)
+{
+	/* Always mark the boot CPU (CPU0) as initialized. */
+	cpumask_set_cpu(0, &tegra_cpu_init_mask);
+
+	if (scu_a9_has_base())
+		scu_enable(IO_ADDRESS(scu_a9_get_base()));
+}
+
+struct smp_operations tegra_smp_ops __initdata = {
+	.smp_prepare_cpus	= tegra_smp_prepare_cpus,
+	.smp_secondary_init	= tegra_secondary_init,
+	.smp_boot_secondary	= tegra_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+	.cpu_kill		= tegra_cpu_kill,
+	.cpu_die		= tegra_cpu_die,
+#endif
+};