Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 390 insertions, 0 deletions

diff --git a/kernel/arch/mips/cavium-octeon/smp.c b/kernel/arch/mips/cavium-octeon/smp.c
new file mode 100644
index 000000000..56f5d080e
--- /dev/null
+++ b/kernel/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
+};