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-rw-r--r--arch/arm/mach-tegra/pm.c216
1 files changed, 216 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/pm.c b/arch/arm/mach-tegra/pm.c
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+++ b/arch/arm/mach-tegra/pm.c
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+/*
+ * CPU complex suspend & resume functions for Tegra SoCs
+ *
+ * Copyright (c) 2009-2012, NVIDIA Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/cpumask.h>
+#include <linux/delay.h>
+#include <linux/cpu_pm.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+
+#include <asm/smp_plat.h>
+#include <asm/cacheflush.h>
+#include <asm/suspend.h>
+#include <asm/idmap.h>
+#include <asm/proc-fns.h>
+#include <asm/tlbflush.h>
+
+#include "iomap.h"
+#include "reset.h"
+#include "flowctrl.h"
+#include "sleep.h"
+#include "tegra_cpu_car.h"
+
+#define TEGRA_POWER_CPU_PWRREQ_OE (1 << 16) /* CPU pwr req enable */
+
+#define PMC_CTRL 0x0
+#define PMC_CPUPWRGOOD_TIMER 0xc8
+#define PMC_CPUPWROFF_TIMER 0xcc
+
+#ifdef CONFIG_PM_SLEEP
+static unsigned int g_diag_reg;
+static DEFINE_SPINLOCK(tegra_lp2_lock);
+static void __iomem *pmc = IO_ADDRESS(TEGRA_PMC_BASE);
+static struct clk *tegra_pclk;
+void (*tegra_tear_down_cpu)(void);
+
+void save_cpu_arch_register(void)
+{
+ /* read diagnostic register */
+ asm("mrc p15, 0, %0, c15, c0, 1" : "=r"(g_diag_reg) : : "cc");
+ return;
+}
+
+void restore_cpu_arch_register(void)
+{
+ /* write diagnostic register */
+ asm("mcr p15, 0, %0, c15, c0, 1" : : "r"(g_diag_reg) : "cc");
+ return;
+}
+
+static void set_power_timers(unsigned long us_on, unsigned long us_off)
+{
+ unsigned long long ticks;
+ unsigned long long pclk;
+ unsigned long rate;
+ static unsigned long tegra_last_pclk;
+
+ if (tegra_pclk == NULL) {
+ tegra_pclk = clk_get_sys(NULL, "pclk");
+ WARN_ON(IS_ERR(tegra_pclk));
+ }
+
+ rate = clk_get_rate(tegra_pclk);
+
+ if (WARN_ON_ONCE(rate <= 0))
+ pclk = 100000000;
+ else
+ pclk = rate;
+
+ if ((rate != tegra_last_pclk)) {
+ ticks = (us_on * pclk) + 999999ull;
+ do_div(ticks, 1000000);
+ writel((unsigned long)ticks, pmc + PMC_CPUPWRGOOD_TIMER);
+
+ ticks = (us_off * pclk) + 999999ull;
+ do_div(ticks, 1000000);
+ writel((unsigned long)ticks, pmc + PMC_CPUPWROFF_TIMER);
+ wmb();
+ }
+ tegra_last_pclk = pclk;
+}
+
+/*
+ * restore_cpu_complex
+ *
+ * restores cpu clock setting, clears flow controller
+ *
+ * Always called on CPU 0.
+ */
+static void restore_cpu_complex(void)
+{
+ int cpu = smp_processor_id();
+
+ BUG_ON(cpu != 0);
+
+#ifdef CONFIG_SMP
+ cpu = cpu_logical_map(cpu);
+#endif
+
+ /* Restore the CPU clock settings */
+ tegra_cpu_clock_resume();
+
+ flowctrl_cpu_suspend_exit(cpu);
+
+ restore_cpu_arch_register();
+}
+
+/*
+ * suspend_cpu_complex
+ *
+ * saves pll state for use by restart_plls, prepares flow controller for
+ * transition to suspend state
+ *
+ * Must always be called on cpu 0.
+ */
+static void suspend_cpu_complex(void)
+{
+ int cpu = smp_processor_id();
+
+ BUG_ON(cpu != 0);
+
+#ifdef CONFIG_SMP
+ cpu = cpu_logical_map(cpu);
+#endif
+
+ /* Save the CPU clock settings */
+ tegra_cpu_clock_suspend();
+
+ flowctrl_cpu_suspend_enter(cpu);
+
+ save_cpu_arch_register();
+}
+
+void __cpuinit tegra_clear_cpu_in_lp2(int phy_cpu_id)
+{
+ u32 *cpu_in_lp2 = tegra_cpu_lp2_mask;
+
+ spin_lock(&tegra_lp2_lock);
+
+ BUG_ON(!(*cpu_in_lp2 & BIT(phy_cpu_id)));
+ *cpu_in_lp2 &= ~BIT(phy_cpu_id);
+
+ spin_unlock(&tegra_lp2_lock);
+}
+
+bool __cpuinit tegra_set_cpu_in_lp2(int phy_cpu_id)
+{
+ bool last_cpu = false;
+ cpumask_t *cpu_lp2_mask = tegra_cpu_lp2_mask;
+ u32 *cpu_in_lp2 = tegra_cpu_lp2_mask;
+
+ spin_lock(&tegra_lp2_lock);
+
+ BUG_ON((*cpu_in_lp2 & BIT(phy_cpu_id)));
+ *cpu_in_lp2 |= BIT(phy_cpu_id);
+
+ if ((phy_cpu_id == 0) && cpumask_equal(cpu_lp2_mask, cpu_online_mask))
+ last_cpu = true;
+
+ spin_unlock(&tegra_lp2_lock);
+ return last_cpu;
+}
+
+static int tegra_sleep_cpu(unsigned long v2p)
+{
+ /* Switch to the identity mapping. */
+ cpu_switch_mm(idmap_pgd, &init_mm);
+
+ /* Flush the TLB. */
+ local_flush_tlb_all();
+
+ tegra_sleep_cpu_finish(v2p);
+
+ /* should never here */
+ BUG();
+
+ return 0;
+}
+
+void tegra_idle_lp2_last(u32 cpu_on_time, u32 cpu_off_time)
+{
+ u32 mode;
+
+ /* Only the last cpu down does the final suspend steps */
+ mode = readl(pmc + PMC_CTRL);
+ mode |= TEGRA_POWER_CPU_PWRREQ_OE;
+ writel(mode, pmc + PMC_CTRL);
+
+ set_power_timers(cpu_on_time, cpu_off_time);
+
+ cpu_cluster_pm_enter();
+ suspend_cpu_complex();
+
+ cpu_suspend(PHYS_OFFSET - PAGE_OFFSET, &tegra_sleep_cpu);
+
+ restore_cpu_complex();
+ cpu_cluster_pm_exit();
+}
+#endif
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