From 45f5984a8a528f7507f3ec860d297934d4449ad1 Mon Sep 17 00:00:00 2001 From: Gregory CLEMENT Date: Wed, 14 Nov 2012 22:51:08 +0100 Subject: arm: mvebu: Add SMP support for Armada XP This enables SMP support on the Armada XP processor. It adds the mandatory functions to support SMP such as: the SMP initialization functions in platsmp.c, the secondary CPU entry point in headsmp.S and the CPU hotplug initial support in hotplug.c. Signed-off-by: Yehuda Yitschak Signed-off-by: Gregory CLEMENT Reviewed-by: Will Deacon --- arch/arm/mach-mvebu/platsmp.c | 122 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 122 insertions(+) create mode 100644 arch/arm/mach-mvebu/platsmp.c (limited to 'arch/arm/mach-mvebu/platsmp.c') diff --git a/arch/arm/mach-mvebu/platsmp.c b/arch/arm/mach-mvebu/platsmp.c new file mode 100644 index 000000000000..fe16aaf7c19c --- /dev/null +++ b/arch/arm/mach-mvebu/platsmp.c @@ -0,0 +1,122 @@ +/* + * Symmetric Multi Processing (SMP) support for Armada XP + * + * Copyright (C) 2012 Marvell + * + * Lior Amsalem + * Yehuda Yitschak + * Gregory CLEMENT + * Thomas Petazzoni + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + * + * The Armada XP SoC has 4 ARMv7 PJ4B CPUs running in full HW coherency + * This file implements the routines for preparing the SMP infrastructure + * and waking up the secondary CPUs + */ + +#include +#include +#include +#include +#include +#include +#include "common.h" +#include "armada-370-xp.h" +#include "pmsu.h" +#include "coherency.h" + +void __init set_secondary_cpus_clock(void) +{ + int thiscpu; + unsigned long rate; + struct clk *cpu_clk = NULL; + struct device_node *np = NULL; + + thiscpu = smp_processor_id(); + for_each_node_by_type(np, "cpu") { + int err; + int cpu; + + err = of_property_read_u32(np, "reg", &cpu); + if (WARN_ON(err)) + return; + + if (cpu == thiscpu) { + cpu_clk = of_clk_get(np, 0); + break; + } + } + if (WARN_ON(IS_ERR(cpu_clk))) + return; + clk_prepare_enable(cpu_clk); + rate = clk_get_rate(cpu_clk); + + /* set all the other CPU clk to the same rate than the boot CPU */ + for_each_node_by_type(np, "cpu") { + int err; + int cpu; + + err = of_property_read_u32(np, "reg", &cpu); + if (WARN_ON(err)) + return; + + if (cpu != thiscpu) { + cpu_clk = of_clk_get(np, 0); + clk_set_rate(cpu_clk, rate); + } + } +} + +static void __cpuinit armada_xp_secondary_init(unsigned int cpu) +{ + armada_xp_mpic_smp_cpu_init(); +} + +static int __cpuinit armada_xp_boot_secondary(unsigned int cpu, + struct task_struct *idle) +{ + pr_info("Booting CPU %d\n", cpu); + + armada_xp_boot_cpu(cpu, armada_xp_secondary_startup); + + return 0; +} + +static void __init armada_xp_smp_init_cpus(void) +{ + unsigned int i, ncores; + ncores = coherency_get_cpu_count(); + + /* Limit possible CPUs to defconfig */ + if (ncores > nr_cpu_ids) { + pr_warn("SMP: %d CPUs physically present. Only %d configured.", + ncores, nr_cpu_ids); + pr_warn("Clipping CPU count to %d\n", nr_cpu_ids); + ncores = nr_cpu_ids; + } + + for (i = 0; i < ncores; i++) + set_cpu_possible(i, true); + + set_smp_cross_call(armada_mpic_send_doorbell); +} + +void __init armada_xp_smp_prepare_cpus(unsigned int max_cpus) +{ + set_secondary_cpus_clock(); + flush_cache_all(); + set_cpu_coherent(cpu_logical_map(smp_processor_id()), 0); +} + +struct smp_operations armada_xp_smp_ops __initdata = { + .smp_init_cpus = armada_xp_smp_init_cpus, + .smp_prepare_cpus = armada_xp_smp_prepare_cpus, + .smp_secondary_init = armada_xp_secondary_init, + .smp_boot_secondary = armada_xp_boot_secondary, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_die = armada_xp_cpu_die, +#endif +}; -- cgit v1.2.3-59-g8ed1b