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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/mips/cavium-octeon/smp.c
Initial import
Diffstat (limited to 'arch/mips/cavium-octeon/smp.c')
-rw-r--r--arch/mips/cavium-octeon/smp.c390
1 files changed, 390 insertions, 0 deletions
diff --git a/arch/mips/cavium-octeon/smp.c b/arch/mips/cavium-octeon/smp.c
new file mode 100644
index 000000000..56f5d080e
--- /dev/null
+++ b/arch/mips/cavium-octeon/smp.c
@@ -0,0 +1,390 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2004-2008, 2009, 2010 Cavium Networks
+ */
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+
+#include <asm/mmu_context.h>
+#include <asm/time.h>
+#include <asm/setup.h>
+
+#include <asm/octeon/octeon.h>
+
+#include "octeon_boot.h"
+
+volatile unsigned long octeon_processor_boot = 0xff;
+volatile unsigned long octeon_processor_sp;
+volatile unsigned long octeon_processor_gp;
+
+#ifdef CONFIG_HOTPLUG_CPU
+uint64_t octeon_bootloader_entry_addr;
+EXPORT_SYMBOL(octeon_bootloader_entry_addr);
+#endif
+
+static irqreturn_t mailbox_interrupt(int irq, void *dev_id)
+{
+ const int coreid = cvmx_get_core_num();
+ uint64_t action;
+
+ /* Load the mailbox register to figure out what we're supposed to do */
+ action = cvmx_read_csr(CVMX_CIU_MBOX_CLRX(coreid)) & 0xffff;
+
+ /* Clear the mailbox to clear the interrupt */
+ cvmx_write_csr(CVMX_CIU_MBOX_CLRX(coreid), action);
+
+ if (action & SMP_CALL_FUNCTION)
+ smp_call_function_interrupt();
+ if (action & SMP_RESCHEDULE_YOURSELF)
+ scheduler_ipi();
+
+ /* Check if we've been told to flush the icache */
+ if (action & SMP_ICACHE_FLUSH)
+ asm volatile ("synci 0($0)\n");
+ return IRQ_HANDLED;
+}
+
+/**
+ * Cause the function described by call_data to be executed on the passed
+ * cpu. When the function has finished, increment the finished field of
+ * call_data.
+ */
+void octeon_send_ipi_single(int cpu, unsigned int action)
+{
+ int coreid = cpu_logical_map(cpu);
+ /*
+ pr_info("SMP: Mailbox send cpu=%d, coreid=%d, action=%u\n", cpu,
+ coreid, action);
+ */
+ cvmx_write_csr(CVMX_CIU_MBOX_SETX(coreid), action);
+}
+
+static inline void octeon_send_ipi_mask(const struct cpumask *mask,
+ unsigned int action)
+{
+ unsigned int i;
+
+ for_each_cpu(i, mask)
+ octeon_send_ipi_single(i, action);
+}
+
+/**
+ * Detect available CPUs, populate cpu_possible_mask
+ */
+static void octeon_smp_hotplug_setup(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ struct linux_app_boot_info *labi;
+
+ if (!setup_max_cpus)
+ return;
+
+ labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
+ if (labi->labi_signature != LABI_SIGNATURE) {
+ pr_info("The bootloader on this board does not support HOTPLUG_CPU.");
+ return;
+ }
+
+ octeon_bootloader_entry_addr = labi->InitTLBStart_addr;
+#endif
+}
+
+static void octeon_smp_setup(void)
+{
+ const int coreid = cvmx_get_core_num();
+ int cpus;
+ int id;
+ int core_mask = octeon_get_boot_coremask();
+#ifdef CONFIG_HOTPLUG_CPU
+ unsigned int num_cores = cvmx_octeon_num_cores();
+#endif
+
+ /* The present CPUs are initially just the boot cpu (CPU 0). */
+ for (id = 0; id < NR_CPUS; id++) {
+ set_cpu_possible(id, id == 0);
+ set_cpu_present(id, id == 0);
+ }
+
+ __cpu_number_map[coreid] = 0;
+ __cpu_logical_map[0] = coreid;
+
+ /* The present CPUs get the lowest CPU numbers. */
+ cpus = 1;
+ for (id = 0; id < NR_CPUS; id++) {
+ if ((id != coreid) && (core_mask & (1 << id))) {
+ set_cpu_possible(cpus, true);
+ set_cpu_present(cpus, true);
+ __cpu_number_map[id] = cpus;
+ __cpu_logical_map[cpus] = id;
+ cpus++;
+ }
+ }
+
+#ifdef CONFIG_HOTPLUG_CPU
+ /*
+ * The possible CPUs are all those present on the chip. We
+ * will assign CPU numbers for possible cores as well. Cores
+ * are always consecutively numberd from 0.
+ */
+ for (id = 0; setup_max_cpus && octeon_bootloader_entry_addr &&
+ id < num_cores && id < NR_CPUS; id++) {
+ if (!(core_mask & (1 << id))) {
+ set_cpu_possible(cpus, true);
+ __cpu_number_map[id] = cpus;
+ __cpu_logical_map[cpus] = id;
+ cpus++;
+ }
+ }
+#endif
+
+ octeon_smp_hotplug_setup();
+}
+
+/**
+ * Firmware CPU startup hook
+ *
+ */
+static void octeon_boot_secondary(int cpu, struct task_struct *idle)
+{
+ int count;
+
+ pr_info("SMP: Booting CPU%02d (CoreId %2d)...\n", cpu,
+ cpu_logical_map(cpu));
+
+ octeon_processor_sp = __KSTK_TOS(idle);
+ octeon_processor_gp = (unsigned long)(task_thread_info(idle));
+ octeon_processor_boot = cpu_logical_map(cpu);
+ mb();
+
+ count = 10000;
+ while (octeon_processor_sp && count) {
+ /* Waiting for processor to get the SP and GP */
+ udelay(1);
+ count--;
+ }
+ if (count == 0)
+ pr_err("Secondary boot timeout\n");
+}
+
+/**
+ * After we've done initial boot, this function is called to allow the
+ * board code to clean up state, if needed
+ */
+static void octeon_init_secondary(void)
+{
+ unsigned int sr;
+
+ sr = set_c0_status(ST0_BEV);
+ write_c0_ebase((u32)ebase);
+ write_c0_status(sr);
+
+ octeon_check_cpu_bist();
+ octeon_init_cvmcount();
+
+ octeon_irq_setup_secondary();
+}
+
+/**
+ * Callout to firmware before smp_init
+ *
+ */
+void octeon_prepare_cpus(unsigned int max_cpus)
+{
+ /*
+ * Only the low order mailbox bits are used for IPIs, leave
+ * the other bits alone.
+ */
+ cvmx_write_csr(CVMX_CIU_MBOX_CLRX(cvmx_get_core_num()), 0xffff);
+ if (request_irq(OCTEON_IRQ_MBOX0, mailbox_interrupt,
+ IRQF_PERCPU | IRQF_NO_THREAD, "SMP-IPI",
+ mailbox_interrupt)) {
+ panic("Cannot request_irq(OCTEON_IRQ_MBOX0)");
+ }
+}
+
+/**
+ * Last chance for the board code to finish SMP initialization before
+ * the CPU is "online".
+ */
+static void octeon_smp_finish(void)
+{
+ octeon_user_io_init();
+
+ /* to generate the first CPU timer interrupt */
+ write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);
+ local_irq_enable();
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+/* State of each CPU. */
+DEFINE_PER_CPU(int, cpu_state);
+
+static int octeon_cpu_disable(void)
+{
+ unsigned int cpu = smp_processor_id();
+
+ if (cpu == 0)
+ return -EBUSY;
+
+ if (!octeon_bootloader_entry_addr)
+ return -ENOTSUPP;
+
+ set_cpu_online(cpu, false);
+ cpumask_clear_cpu(cpu, &cpu_callin_map);
+ octeon_fixup_irqs();
+
+ flush_cache_all();
+ local_flush_tlb_all();
+
+ return 0;
+}
+
+static void octeon_cpu_die(unsigned int cpu)
+{
+ int coreid = cpu_logical_map(cpu);
+ uint32_t mask, new_mask;
+ const struct cvmx_bootmem_named_block_desc *block_desc;
+
+ while (per_cpu(cpu_state, cpu) != CPU_DEAD)
+ cpu_relax();
+
+ /*
+ * This is a bit complicated strategics of getting/settig available
+ * cores mask, copied from bootloader
+ */
+
+ mask = 1 << coreid;
+ /* LINUX_APP_BOOT_BLOCK is initialized in bootoct binary */
+ block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
+
+ if (!block_desc) {
+ struct linux_app_boot_info *labi;
+
+ labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
+
+ labi->avail_coremask |= mask;
+ new_mask = labi->avail_coremask;
+ } else { /* alternative, already initialized */
+ uint32_t *p = (uint32_t *)PHYS_TO_XKSEG_CACHED(block_desc->base_addr +
+ AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
+ *p |= mask;
+ new_mask = *p;
+ }
+
+ pr_info("Reset core %d. Available Coremask = 0x%x \n", coreid, new_mask);
+ mb();
+ cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
+ cvmx_write_csr(CVMX_CIU_PP_RST, 0);
+}
+
+void play_dead(void)
+{
+ int cpu = cpu_number_map(cvmx_get_core_num());
+
+ idle_task_exit();
+ octeon_processor_boot = 0xff;
+ per_cpu(cpu_state, cpu) = CPU_DEAD;
+
+ mb();
+
+ while (1) /* core will be reset here */
+ ;
+}
+
+extern void kernel_entry(unsigned long arg1, ...);
+
+static void start_after_reset(void)
+{
+ kernel_entry(0, 0, 0); /* set a2 = 0 for secondary core */
+}
+
+static int octeon_update_boot_vector(unsigned int cpu)
+{
+
+ int coreid = cpu_logical_map(cpu);
+ uint32_t avail_coremask;
+ const struct cvmx_bootmem_named_block_desc *block_desc;
+ struct boot_init_vector *boot_vect =
+ (struct boot_init_vector *)PHYS_TO_XKSEG_CACHED(BOOTLOADER_BOOT_VECTOR);
+
+ block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
+
+ if (!block_desc) {
+ struct linux_app_boot_info *labi;
+
+ labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
+
+ avail_coremask = labi->avail_coremask;
+ labi->avail_coremask &= ~(1 << coreid);
+ } else { /* alternative, already initialized */
+ avail_coremask = *(uint32_t *)PHYS_TO_XKSEG_CACHED(
+ block_desc->base_addr + AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
+ }
+
+ if (!(avail_coremask & (1 << coreid))) {
+ /* core not available, assume, that catched by simple-executive */
+ cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
+ cvmx_write_csr(CVMX_CIU_PP_RST, 0);
+ }
+
+ boot_vect[coreid].app_start_func_addr =
+ (uint32_t) (unsigned long) start_after_reset;
+ boot_vect[coreid].code_addr = octeon_bootloader_entry_addr;
+
+ mb();
+
+ cvmx_write_csr(CVMX_CIU_NMI, (1 << coreid) & avail_coremask);
+
+ return 0;
+}
+
+static int octeon_cpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long)hcpu;
+
+ switch (action) {
+ case CPU_UP_PREPARE:
+ octeon_update_boot_vector(cpu);
+ break;
+ case CPU_ONLINE:
+ pr_info("Cpu %d online\n", cpu);
+ break;
+ case CPU_DEAD:
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static int register_cavium_notifier(void)
+{
+ hotcpu_notifier(octeon_cpu_callback, 0);
+ return 0;
+}
+late_initcall(register_cavium_notifier);
+
+#endif /* CONFIG_HOTPLUG_CPU */
+
+struct plat_smp_ops octeon_smp_ops = {
+ .send_ipi_single = octeon_send_ipi_single,
+ .send_ipi_mask = octeon_send_ipi_mask,
+ .init_secondary = octeon_init_secondary,
+ .smp_finish = octeon_smp_finish,
+ .boot_secondary = octeon_boot_secondary,
+ .smp_setup = octeon_smp_setup,
+ .prepare_cpus = octeon_prepare_cpus,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_disable = octeon_cpu_disable,
+ .cpu_die = octeon_cpu_die,
+#endif
+};