diff options
Diffstat (limited to 'arch/arm/mach-socfpga/platsmp.c')
-rw-r--r-- | arch/arm/mach-socfpga/platsmp.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/arch/arm/mach-socfpga/platsmp.c b/arch/arm/mach-socfpga/platsmp.c new file mode 100644 index 000000000..a272999ce --- /dev/null +++ b/arch/arm/mach-socfpga/platsmp.c @@ -0,0 +1,141 @@ +/* + * Copyright 2010-2011 Calxeda, Inc. + * Copyright 2012 Pavel Machek <pavel@denx.de> + * Based on platsmp.c, Copyright (C) 2002 ARM Ltd. + * Copyright (C) 2012 Altera Corporation + * + * 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/delay.h> +#include <linux/init.h> +#include <linux/smp.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> + +#include <asm/cacheflush.h> +#include <asm/smp_scu.h> +#include <asm/smp_plat.h> + +#include "core.h" + +static int socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle) +{ + int trampoline_size = secondary_trampoline_end - secondary_trampoline; + + if (socfpga_cpu1start_addr) { + /* This will put CPU #1 into reset. */ + writel(RSTMGR_MPUMODRST_CPU1, + rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST); + + memcpy(phys_to_virt(0), secondary_trampoline, trampoline_size); + + writel(__pa_symbol(secondary_startup), + sys_manager_base_addr + (socfpga_cpu1start_addr & 0x000000ff)); + + flush_cache_all(); + smp_wmb(); + outer_clean_range(0, trampoline_size); + + /* This will release CPU #1 out of reset. */ + writel(0, rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST); + } + + return 0; +} + +static int socfpga_a10_boot_secondary(unsigned int cpu, struct task_struct *idle) +{ + int trampoline_size = secondary_trampoline_end - secondary_trampoline; + + if (socfpga_cpu1start_addr) { + writel(RSTMGR_MPUMODRST_CPU1, rst_manager_base_addr + + SOCFPGA_A10_RSTMGR_MODMPURST); + memcpy(phys_to_virt(0), secondary_trampoline, trampoline_size); + + writel(__pa_symbol(secondary_startup), + sys_manager_base_addr + (socfpga_cpu1start_addr & 0x00000fff)); + + flush_cache_all(); + smp_wmb(); + outer_clean_range(0, trampoline_size); + + /* This will release CPU #1 out of reset. */ + writel(0, rst_manager_base_addr + SOCFPGA_A10_RSTMGR_MODMPURST); + } + + return 0; +} + +static void __init socfpga_smp_prepare_cpus(unsigned int max_cpus) +{ + struct device_node *np; + void __iomem *socfpga_scu_base_addr; + + np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu"); + if (!np) { + pr_err("%s: missing scu\n", __func__); + return; + } + + socfpga_scu_base_addr = of_iomap(np, 0); + if (!socfpga_scu_base_addr) + return; + scu_enable(socfpga_scu_base_addr); +} + +#ifdef CONFIG_HOTPLUG_CPU +/* + * platform-specific code to shutdown a CPU + * + * Called with IRQs disabled + */ +static void socfpga_cpu_die(unsigned int cpu) +{ + /* Do WFI. If we wake up early, go back into WFI */ + while (1) + cpu_do_idle(); +} + +/* + * We need a dummy function so that platform_can_cpu_hotplug() knows + * we support CPU hotplug. However, the function does not need to do + * anything, because CPUs going offline just do WFI. We could reset + * the CPUs but it would increase power consumption. + */ +static int socfpga_cpu_kill(unsigned int cpu) +{ + return 1; +} +#endif + +static const struct smp_operations socfpga_smp_ops __initconst = { + .smp_prepare_cpus = socfpga_smp_prepare_cpus, + .smp_boot_secondary = socfpga_boot_secondary, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_die = socfpga_cpu_die, + .cpu_kill = socfpga_cpu_kill, +#endif +}; + +static const struct smp_operations socfpga_a10_smp_ops __initconst = { + .smp_prepare_cpus = socfpga_smp_prepare_cpus, + .smp_boot_secondary = socfpga_a10_boot_secondary, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_die = socfpga_cpu_die, + .cpu_kill = socfpga_cpu_kill, +#endif +}; + +CPU_METHOD_OF_DECLARE(socfpga_smp, "altr,socfpga-smp", &socfpga_smp_ops); +CPU_METHOD_OF_DECLARE(socfpga_a10_smp, "altr,socfpga-a10-smp", &socfpga_a10_smp_ops); |