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87e1bed406
The changes needed to migrate the mach-mvebu (Armada 370 and Armada XP) to the mvebu-mbus driver are fairly minimal, since not many devices currently supported on those SoCs use address decoding windows. The only one being the BootROM window, used to bring up secondary CPUs. However, this BootROM window needed for SMP brings an important requirement: the mvebu-mbus driver must be initialized at the ->early_init() time, otherwise the BootROM window cannot be setup early enough to be ready before the secondary CPUs are started. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jason Cooper <jason@lakedaemon.net>
124 lines
3 KiB
C
124 lines
3 KiB
C
/*
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* Symmetric Multi Processing (SMP) support for Armada XP
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*
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* Copyright (C) 2012 Marvell
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*
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* Lior Amsalem <alior@marvell.com>
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* Yehuda Yitschak <yehuday@marvell.com>
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* Gregory CLEMENT <gregory.clement@free-electrons.com>
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* Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
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*
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* This file is licensed under the terms of the GNU General Public
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* License version 2. This program is licensed "as is" without any
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* warranty of any kind, whether express or implied.
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*
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* The Armada XP SoC has 4 ARMv7 PJ4B CPUs running in full HW coherency
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* This file implements the routines for preparing the SMP infrastructure
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* and waking up the secondary CPUs
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*/
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#include <linux/init.h>
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#include <linux/smp.h>
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#include <linux/clk.h>
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#include <linux/of.h>
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#include <linux/mbus.h>
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#include <asm/cacheflush.h>
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#include <asm/smp_plat.h>
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#include "common.h"
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#include "armada-370-xp.h"
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#include "pmsu.h"
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#include "coherency.h"
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void __init set_secondary_cpus_clock(void)
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{
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int thiscpu;
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unsigned long rate;
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struct clk *cpu_clk = NULL;
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struct device_node *np = NULL;
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thiscpu = smp_processor_id();
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for_each_node_by_type(np, "cpu") {
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int err;
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int cpu;
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err = of_property_read_u32(np, "reg", &cpu);
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if (WARN_ON(err))
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return;
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if (cpu == thiscpu) {
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cpu_clk = of_clk_get(np, 0);
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break;
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}
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}
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if (WARN_ON(IS_ERR(cpu_clk)))
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return;
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clk_prepare_enable(cpu_clk);
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rate = clk_get_rate(cpu_clk);
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/* set all the other CPU clk to the same rate than the boot CPU */
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for_each_node_by_type(np, "cpu") {
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int err;
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int cpu;
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err = of_property_read_u32(np, "reg", &cpu);
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if (WARN_ON(err))
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return;
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if (cpu != thiscpu) {
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cpu_clk = of_clk_get(np, 0);
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clk_set_rate(cpu_clk, rate);
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}
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}
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}
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static void __cpuinit armada_xp_secondary_init(unsigned int cpu)
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{
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armada_xp_mpic_smp_cpu_init();
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}
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static int __cpuinit armada_xp_boot_secondary(unsigned int cpu,
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struct task_struct *idle)
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{
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pr_info("Booting CPU %d\n", cpu);
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armada_xp_boot_cpu(cpu, armada_xp_secondary_startup);
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return 0;
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}
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static void __init armada_xp_smp_init_cpus(void)
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{
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unsigned int i, ncores;
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ncores = coherency_get_cpu_count();
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/* Limit possible CPUs to defconfig */
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if (ncores > nr_cpu_ids) {
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pr_warn("SMP: %d CPUs physically present. Only %d configured.",
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ncores, nr_cpu_ids);
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pr_warn("Clipping CPU count to %d\n", nr_cpu_ids);
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ncores = nr_cpu_ids;
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}
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for (i = 0; i < ncores; i++)
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set_cpu_possible(i, true);
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set_smp_cross_call(armada_mpic_send_doorbell);
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}
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void __init armada_xp_smp_prepare_cpus(unsigned int max_cpus)
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{
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set_secondary_cpus_clock();
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flush_cache_all();
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set_cpu_coherent(cpu_logical_map(smp_processor_id()), 0);
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mvebu_mbus_add_window("bootrom", 0xfff00000, SZ_1M);
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}
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struct smp_operations armada_xp_smp_ops __initdata = {
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.smp_init_cpus = armada_xp_smp_init_cpus,
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.smp_prepare_cpus = armada_xp_smp_prepare_cpus,
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.smp_secondary_init = armada_xp_secondary_init,
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.smp_boot_secondary = armada_xp_boot_secondary,
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#ifdef CONFIG_HOTPLUG_CPU
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.cpu_die = armada_xp_cpu_die,
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#endif
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};
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