diff options
Diffstat (limited to 'arch/arm/mach-tegra/platsmp.c')
| -rw-r--r-- | arch/arm/mach-tegra/platsmp.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/platsmp.c b/arch/arm/mach-tegra/platsmp.c new file mode 100644 index 00000000..1a208dbf --- /dev/null +++ b/arch/arm/mach-tegra/platsmp.c @@ -0,0 +1,188 @@ +/* + * 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/init.h> +#include <linux/errno.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/jiffies.h> +#include <linux/smp.h> +#include <linux/io.h> + +#include <asm/cacheflush.h> +#include <asm/hardware/gic.h> +#include <asm/mach-types.h> +#include <asm/smp_scu.h> + +#include <mach/clk.h> +#include <mach/iomap.h> +#include <mach/powergate.h> + +#include "fuse.h" +#include "flowctrl.h" +#include "reset.h" + +extern void tegra_secondary_startup(void); + +static void __iomem *scu_base = IO_ADDRESS(TEGRA_ARM_PERIF_BASE); + +#define EVP_CPU_RESET_VECTOR \ + (IO_ADDRESS(TEGRA_EXCEPTION_VECTORS_BASE) + 0x100) +#define CLK_RST_CONTROLLER_CLK_CPU_CMPLX \ + (IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x4c) +#define CLK_RST_CONTROLLER_RST_CPU_CMPLX_SET \ + (IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x340) +#define CLK_RST_CONTROLLER_RST_CPU_CMPLX_CLR \ + (IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x344) +#define CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR \ + (IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x34c) + +#define CPU_CLOCK(cpu) (0x1<<(8+cpu)) +#define CPU_RESET(cpu) (0x1111ul<<(cpu)) + +void __cpuinit platform_secondary_init(unsigned int cpu) +{ + /* + * if any interrupts are already enabled for the primary + * core (e.g. timer irq), then they will not have been enabled + * for us: do so + */ + gic_secondary_init(0); + +} + +static int tegra20_power_up_cpu(unsigned int cpu) +{ + u32 reg; + + /* Enable the CPU clock. */ + reg = readl(CLK_RST_CONTROLLER_CLK_CPU_CMPLX); + writel(reg & ~CPU_CLOCK(cpu), CLK_RST_CONTROLLER_CLK_CPU_CMPLX); + barrier(); + reg = readl(CLK_RST_CONTROLLER_CLK_CPU_CMPLX); + + /* Clear flow controller CSR. */ + flowctrl_write_cpu_csr(cpu, 0); + + return 0; +} + +static int tegra30_power_up_cpu(unsigned int cpu) +{ + u32 reg; + int ret, pwrgateid; + unsigned long timeout; + + pwrgateid = tegra_cpu_powergate_id(cpu); + if (pwrgateid < 0) + return pwrgateid; + + /* If this is the first boot, toggle powergates directly. */ + if (!tegra_powergate_is_powered(pwrgateid)) { + ret = tegra_powergate_power_on(pwrgateid); + if (ret) + return ret; + + /* Wait for the power to come up. */ + timeout = jiffies + 10*HZ; + while (tegra_powergate_is_powered(pwrgateid)) { + if (time_after(jiffies, timeout)) + return -ETIMEDOUT; + udelay(10); + } + } + + /* CPU partition is powered. Enable the CPU clock. */ + writel(CPU_CLOCK(cpu), CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR); + reg = readl(CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR); + udelay(10); + + /* Remove I/O clamps. */ + ret = tegra_powergate_remove_clamping(pwrgateid); + udelay(10); + + /* Clear flow controller CSR. */ + flowctrl_write_cpu_csr(cpu, 0); + + return 0; +} + +int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) +{ + int status; + + /* + * 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. + */ + writel(CPU_RESET(cpu), CLK_RST_CONTROLLER_RST_CPU_CMPLX_SET); + dmb(); + + /* + * 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); + + switch (tegra_chip_id) { + case TEGRA20: + status = tegra20_power_up_cpu(cpu); + break; + case TEGRA30: + status = tegra30_power_up_cpu(cpu); + break; + default: + status = -EINVAL; + break; + } + + if (status) + goto done; + + /* Take the CPU out of reset. */ + writel(CPU_RESET(cpu), CLK_RST_CONTROLLER_RST_CPU_CMPLX_CLR); + wmb(); +done: + return status; +} + +/* + * Initialise the CPU possible map early - this describes the CPUs + * which may be present or become present in the system. + */ +void __init smp_init_cpus(void) +{ + unsigned int i, ncores = scu_get_core_count(scu_base); + + if (ncores > nr_cpu_ids) { + pr_warn("SMP: %u cores greater than maximum (%u), clipping\n", + ncores, nr_cpu_ids); + ncores = nr_cpu_ids; + } + + for (i = 0; i < ncores; i++) + set_cpu_possible(i, true); + + set_smp_cross_call(gic_raise_softirq); +} + +void __init platform_smp_prepare_cpus(unsigned int max_cpus) +{ + tegra_cpu_reset_handler_init(); + scu_enable(scu_base); +} |