MIPS: Add code for new system 'paravirt'

For para-virtualized guests running under KVM or other equivalent
hypervisor.

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7004/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

11 files changed, 777 insertions, 6 deletions

diff --git a/arch/mips/include/asm/mach-paravirt/cpu-feature-overrides.h b/arch/mips/include/asm/mach-paravirt/cpu-feature-overrides.h
new file mode 100644
index 000000000000..725e1ed83f6a
--- /dev/null
+++ b/arch/mips/include/asm/mach-paravirt/cpu-feature-overrides.h
@@ -0,0 +1,36 @@
+/*
+ * 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) 2013 Cavium, Inc.
+ */
+#ifndef __ASM_MACH_PARAVIRT_CPU_FEATURE_OVERRIDES_H
+#define __ASM_MACH_PARAVIRT_CPU_FEATURE_OVERRIDES_H
+
+#define cpu_has_4kex            1
+#define cpu_has_3k_cache        0
+#define cpu_has_tx39_cache      0
+#define cpu_has_counter         1
+#define cpu_has_llsc            1
+/*
+ * We Disable LL/SC on non SMP systems as it is faster to disable
+ * interrupts for atomic access than a LL/SC.
+ */
+#ifdef CONFIG_SMP
+# define kernel_uses_llsc       1
+#else
+# define kernel_uses_llsc       0
+#endif
+
+#ifdef CONFIG_CPU_CAVIUM_OCTEON
+#define cpu_dcache_line_size()  128
+#define cpu_icache_line_size()  128
+#define cpu_has_octeon_cache    1
+#define cpu_has_4k_cache        0
+#else
+#define cpu_has_octeon_cache    0
+#define cpu_has_4k_cache        1
+#endif
+
+#endif /* __ASM_MACH_PARAVIRT_CPU_FEATURE_OVERRIDES_H */
diff --git a/arch/mips/include/asm/mach-paravirt/irq.h b/arch/mips/include/asm/mach-paravirt/irq.h
new file mode 100644
index 000000000000..9b4d35eca977
--- /dev/null
+++ b/arch/mips/include/asm/mach-paravirt/irq.h
@@ -0,0 +1,19 @@
+/*
+ * 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) 2013 Cavium, Inc.
+ */
+#ifndef __ASM_MACH_PARAVIRT_IRQ_H__
+#define  __ASM_MACH_PARAVIRT_IRQ_H__
+
+#define NR_IRQS 64
+#define MIPS_CPU_IRQ_BASE 1
+
+#define MIPS_IRQ_PCIA (MIPS_CPU_IRQ_BASE + 8)
+
+#define MIPS_IRQ_MBOX0 (MIPS_CPU_IRQ_BASE + 32)
+#define MIPS_IRQ_MBOX1 (MIPS_CPU_IRQ_BASE + 33)
+
+#endif /* __ASM_MACH_PARAVIRT_IRQ_H__ */
diff --git a/arch/mips/include/asm/mach-paravirt/kernel-entry-init.h b/arch/mips/include/asm/mach-paravirt/kernel-entry-init.h
new file mode 100644
index 000000000000..2f82bfa3a773
--- /dev/null
+++ b/arch/mips/include/asm/mach-paravirt/kernel-entry-init.h
@@ -0,0 +1,50 @@
+/*
+ * 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) 2013 Cavium, Inc
+ */
+#ifndef __ASM_MACH_PARAVIRT_KERNEL_ENTRY_H
+#define __ASM_MACH_PARAVIRT_KERNEL_ENTRY_H
+
+#define CP0_EBASE $15, 1
+
+        .macro  kernel_entry_setup
+        mfc0    t0, CP0_EBASE
+        andi    t0, t0, 0x3ff           # CPUNum
+        beqz    t0, 1f
+        # CPUs other than zero goto smp_bootstrap
+        j       smp_bootstrap
+
+1:
+        .endm
+
+/*
+ * Do SMP slave processor setup necessary before we can safely execute
+ * C code.
+ */
+        .macro  smp_slave_setup
+        mfc0    t0, CP0_EBASE
+        andi    t0, t0, 0x3ff           # CPUNum
+        slti    t1, t0, NR_CPUS
+        bnez    t1, 1f
+2:
+        di
+        wait
+        b       2b                      # Unknown CPU, loop forever.
+1:
+        PTR_LA  t1, paravirt_smp_sp
+        PTR_SLL t0, PTR_SCALESHIFT
+        PTR_ADDU t1, t1, t0
+3:
+        PTR_L   sp, 0(t1)
+        beqz    sp, 3b                  # Spin until told to proceed.
+
+        PTR_LA  t1, paravirt_smp_gp
+        PTR_ADDU t1, t1, t0
+        sync
+        PTR_L   gp, 0(t1)
+        .endm
+
+#endif /* __ASM_MACH_PARAVIRT_KERNEL_ENTRY_H */
diff --git a/arch/mips/include/asm/mach-paravirt/war.h b/arch/mips/include/asm/mach-paravirt/war.h
new file mode 100644
index 000000000000..36d3afb98451
--- /dev/null
+++ b/arch/mips/include/asm/mach-paravirt/war.h
@@ -0,0 +1,25 @@
+/*
+ * 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) 2002, 2004, 2007 by Ralf Baechle <ralf@linux-mips.org>
+ * Copyright (C) 2013 Cavium Networks <support@caviumnetworks.com>
+ */
+#ifndef __ASM_MIPS_MACH_PARAVIRT_WAR_H
+#define __ASM_MIPS_MACH_PARAVIRT_WAR_H
+
+#define R4600_V1_INDEX_ICACHEOP_WAR     0
+#define R4600_V1_HIT_CACHEOP_WAR        0
+#define R4600_V2_HIT_CACHEOP_WAR        0
+#define R5432_CP0_INTERRUPT_WAR         0
+#define BCM1250_M3_WAR                  0
+#define SIBYTE_1956_WAR                 0
+#define MIPS4K_ICACHE_REFILL_WAR        0
+#define MIPS_CACHE_SYNC_WAR             0
+#define TX49XX_ICACHE_INDEX_INV_WAR     0
+#define ICACHE_REFILLS_WORKAROUND_WAR   0
+#define R10000_LLSC_WAR                 0
+#define MIPS34K_MISSED_ITLB_WAR         0
+
+#endif /* __ASM_MIPS_MACH_PARAVIRT_WAR_H */
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index af91f3ed1a82..e80e10bafc83 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -1250,17 +1250,13 @@ static void build_r4000_tlb_refill_handler(void)
         unsigned int final_len;
         struct mips_huge_tlb_info htlb_info __maybe_unused;
         enum vmalloc64_mode vmalloc_mode __maybe_unused;
-#ifdef CONFIG_64BIT
-        bool is64bit = true;
-#else
-        bool is64bit = false;
-#endif
+
         memset(tlb_handler, 0, sizeof(tlb_handler));
         memset(labels, 0, sizeof(labels));
         memset(relocs, 0, sizeof(relocs));
         memset(final_handler, 0, sizeof(final_handler));
 
-        if (is64bit && (scratch_reg >= 0 || scratchpad_available()) && use_bbit_insns()) {
+        if (IS_ENABLED(CONFIG_64BIT) && (scratch_reg >= 0 || scratchpad_available()) && use_bbit_insns()) {
                 htlb_info = build_fast_tlb_refill_handler(&p, &l, &r, K0, K1,
                                                           scratch_reg);
                 vmalloc_mode = refill_scratch;
diff --git a/arch/mips/paravirt/Makefile b/arch/mips/paravirt/Makefile
new file mode 100644
index 000000000000..5023af733a35
--- /dev/null
+++ b/arch/mips/paravirt/Makefile
@@ -0,0 +1,14 @@
+#
+# Makefile for MIPS para-virtualized specific kernel interface routines
+# under Linux.
+#
+# 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) 2013 Cavium, Inc.
+#
+
+obj-y := setup.o serial.o paravirt-irq.o
+
+obj-$(CONFIG_SMP)               += paravirt-smp.o
diff --git a/arch/mips/paravirt/Platform b/arch/mips/paravirt/Platform
new file mode 100644
index 000000000000..7e76ef25ea17
--- /dev/null
+++ b/arch/mips/paravirt/Platform
@@ -0,0 +1,8 @@
+#
+# Generic para-virtualized guest.
+#
+platform-$(CONFIG_MIPS_PARAVIRT)        += paravirt/
+cflags-$(CONFIG_MIPS_PARAVIRT)          +=                              \
+                -I$(srctree)/arch/mips/include/asm/mach-paravirt
+
+load-$(CONFIG_MIPS_PARAVIRT)    = 0xffffffff80010000
diff --git a/arch/mips/paravirt/paravirt-irq.c b/arch/mips/paravirt/paravirt-irq.c
new file mode 100644
index 000000000000..8987b06c9de9
--- /dev/null
+++ b/arch/mips/paravirt/paravirt-irq.c
@@ -0,0 +1,368 @@
+/*
+ * 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) 2013 Cavium, Inc.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/cpumask.h>
+#include <linux/kernel.h>
+#include <linux/mutex.h>
+
+#include <asm/io.h>
+
+#define MBOX_BITS_PER_CPU 2
+
+static int cpunum_for_cpu(int cpu)
+{
+#ifdef CONFIG_SMP
+        return cpu_logical_map(cpu);
+#else
+        return get_ebase_cpunum();
+#endif
+}
+
+struct core_chip_data {
+        struct mutex core_irq_mutex;
+        bool current_en;
+        bool desired_en;
+        u8 bit;
+};
+
+static struct core_chip_data irq_core_chip_data[8];
+
+static void irq_core_ack(struct irq_data *data)
+{
+        struct core_chip_data *cd = irq_data_get_irq_chip_data(data);
+        unsigned int bit = cd->bit;
+
+        /*
+         * We don't need to disable IRQs to make these atomic since
+         * they are already disabled earlier in the low level
+         * interrupt code.
+         */
+        clear_c0_status(0x100 << bit);
+        /* The two user interrupts must be cleared manually. */
+        if (bit < 2)
+                clear_c0_cause(0x100 << bit);
+}
+
+static void irq_core_eoi(struct irq_data *data)
+{
+        struct core_chip_data *cd = irq_data_get_irq_chip_data(data);
+
+        /*
+         * We don't need to disable IRQs to make these atomic since
+         * they are already disabled earlier in the low level
+         * interrupt code.
+         */
+        set_c0_status(0x100 << cd->bit);
+}
+
+static void irq_core_set_enable_local(void *arg)
+{
+        struct irq_data *data = arg;
+        struct core_chip_data *cd = irq_data_get_irq_chip_data(data);
+        unsigned int mask = 0x100 << cd->bit;
+
+        /*
+         * Interrupts are already disabled, so these are atomic.
+         */
+        if (cd->desired_en)
+                set_c0_status(mask);
+        else
+                clear_c0_status(mask);
+
+}
+
+static void irq_core_disable(struct irq_data *data)
+{
+        struct core_chip_data *cd = irq_data_get_irq_chip_data(data);
+        cd->desired_en = false;
+}
+
+static void irq_core_enable(struct irq_data *data)
+{
+        struct core_chip_data *cd = irq_data_get_irq_chip_data(data);
+        cd->desired_en = true;
+}
+
+static void irq_core_bus_lock(struct irq_data *data)
+{
+        struct core_chip_data *cd = irq_data_get_irq_chip_data(data);
+
+        mutex_lock(&cd->core_irq_mutex);
+}
+
+static void irq_core_bus_sync_unlock(struct irq_data *data)
+{
+        struct core_chip_data *cd = irq_data_get_irq_chip_data(data);
+
+        if (cd->desired_en != cd->current_en) {
+                on_each_cpu(irq_core_set_enable_local, data, 1);
+                cd->current_en = cd->desired_en;
+        }
+
+        mutex_unlock(&cd->core_irq_mutex);
+}
+
+static struct irq_chip irq_chip_core = {
+        .name = "Core",
+        .irq_enable = irq_core_enable,
+        .irq_disable = irq_core_disable,
+        .irq_ack = irq_core_ack,
+        .irq_eoi = irq_core_eoi,
+        .irq_bus_lock = irq_core_bus_lock,
+        .irq_bus_sync_unlock = irq_core_bus_sync_unlock,
+
+        .irq_cpu_online = irq_core_eoi,
+        .irq_cpu_offline = irq_core_ack,
+        .flags = IRQCHIP_ONOFFLINE_ENABLED,
+};
+
+static void __init irq_init_core(void)
+{
+        int i;
+        int irq;
+        struct core_chip_data *cd;
+
+        /* Start with a clean slate */
+        clear_c0_status(ST0_IM);
+        clear_c0_cause(CAUSEF_IP0 | CAUSEF_IP1);
+
+        for (i = 0; i < ARRAY_SIZE(irq_core_chip_data); i++) {
+                cd = irq_core_chip_data + i;
+                cd->current_en = false;
+                cd->desired_en = false;
+                cd->bit = i;
+                mutex_init(&cd->core_irq_mutex);
+
+                irq = MIPS_CPU_IRQ_BASE + i;
+
+                switch (i) {
+                case 0: /* SW0 */
+                case 1: /* SW1 */
+                case 5: /* IP5 */
+                case 6: /* IP6 */
+                case 7: /* IP7 */
+                        irq_set_chip_data(irq, cd);
+                        irq_set_chip_and_handler(irq, &irq_chip_core,
+                                                 handle_percpu_irq);
+                        break;
+                default:
+                        break;
+                }
+        }
+}
+
+static void __iomem *mips_irq_chip;
+#define MIPS_IRQ_CHIP_NUM_BITS 0
+#define MIPS_IRQ_CHIP_REGS 8
+
+static int mips_irq_cpu_stride;
+static int mips_irq_chip_reg_raw;
+static int mips_irq_chip_reg_src;
+static int mips_irq_chip_reg_en;
+static int mips_irq_chip_reg_raw_w1s;
+static int mips_irq_chip_reg_raw_w1c;
+static int mips_irq_chip_reg_en_w1s;
+static int mips_irq_chip_reg_en_w1c;
+
+static void irq_pci_enable(struct irq_data *data)
+{
+        u32 mask = 1u << data->irq;
+
+        __raw_writel(mask, mips_irq_chip + mips_irq_chip_reg_en_w1s);
+}
+
+static void irq_pci_disable(struct irq_data *data)
+{
+        u32 mask = 1u << data->irq;
+
+        __raw_writel(mask, mips_irq_chip + mips_irq_chip_reg_en_w1c);
+}
+
+static void irq_pci_ack(struct irq_data *data)
+{
+}
+
+static void irq_pci_mask(struct irq_data *data)
+{
+        u32 mask = 1u << data->irq;
+
+        __raw_writel(mask, mips_irq_chip + mips_irq_chip_reg_en_w1c);
+}
+
+static void irq_pci_unmask(struct irq_data *data)
+{
+        u32 mask = 1u << data->irq;
+
+        __raw_writel(mask, mips_irq_chip + mips_irq_chip_reg_en_w1s);
+}
+
+static struct irq_chip irq_chip_pci = {
+        .name = "PCI",
+        .irq_enable = irq_pci_enable,
+        .irq_disable = irq_pci_disable,
+        .irq_ack = irq_pci_ack,
+        .irq_mask = irq_pci_mask,
+        .irq_unmask = irq_pci_unmask,
+};
+
+static void irq_mbox_all(struct irq_data *data,  void __iomem *base)
+{
+        int cpu;
+        unsigned int mbox = data->irq - MIPS_IRQ_MBOX0;
+        u32 mask;
+
+        WARN_ON(mbox >= MBOX_BITS_PER_CPU);
+
+        for_each_online_cpu(cpu) {
+                unsigned int cpuid = cpunum_for_cpu(cpu);
+                mask = 1 << (cpuid * MBOX_BITS_PER_CPU + mbox);
+                __raw_writel(mask, base + (cpuid * mips_irq_cpu_stride));
+        }
+}
+
+static void irq_mbox_enable(struct irq_data *data)
+{
+        irq_mbox_all(data, mips_irq_chip + mips_irq_chip_reg_en_w1s + sizeof(u32));
+}
+
+static void irq_mbox_disable(struct irq_data *data)
+{
+        irq_mbox_all(data, mips_irq_chip + mips_irq_chip_reg_en_w1c + sizeof(u32));
+}
+
+static void irq_mbox_ack(struct irq_data *data)
+{
+        u32 mask;
+        unsigned int mbox = data->irq - MIPS_IRQ_MBOX0;
+
+        WARN_ON(mbox >= MBOX_BITS_PER_CPU);
+
+        mask = 1 << (get_ebase_cpunum() * MBOX_BITS_PER_CPU + mbox);
+        __raw_writel(mask, mips_irq_chip + mips_irq_chip_reg_raw_w1c + sizeof(u32));
+}
+
+void irq_mbox_ipi(int cpu, unsigned int actions)
+{
+        unsigned int cpuid = cpunum_for_cpu(cpu);
+        u32 mask;
+
+        WARN_ON(actions >= (1 << MBOX_BITS_PER_CPU));
+
+        mask = actions << (cpuid * MBOX_BITS_PER_CPU);
+        __raw_writel(mask, mips_irq_chip + mips_irq_chip_reg_raw_w1s + sizeof(u32));
+}
+
+static void irq_mbox_cpu_onoffline(struct irq_data *data,  void __iomem *base)
+{
+        unsigned int mbox = data->irq - MIPS_IRQ_MBOX0;
+        unsigned int cpuid = get_ebase_cpunum();
+        u32 mask;
+
+        WARN_ON(mbox >= MBOX_BITS_PER_CPU);
+
+        mask = 1 << (cpuid * MBOX_BITS_PER_CPU + mbox);
+        __raw_writel(mask, base + (cpuid * mips_irq_cpu_stride));
+
+}
+
+static void irq_mbox_cpu_online(struct irq_data *data)
+{
+        irq_mbox_cpu_onoffline(data, mips_irq_chip + mips_irq_chip_reg_en_w1s + sizeof(u32));
+}
+
+static void irq_mbox_cpu_offline(struct irq_data *data)
+{
+        irq_mbox_cpu_onoffline(data, mips_irq_chip + mips_irq_chip_reg_en_w1c + sizeof(u32));
+}
+
+static struct irq_chip irq_chip_mbox = {
+        .name = "MBOX",
+        .irq_enable = irq_mbox_enable,
+        .irq_disable = irq_mbox_disable,
+        .irq_ack = irq_mbox_ack,
+        .irq_cpu_online = irq_mbox_cpu_online,
+        .irq_cpu_offline = irq_mbox_cpu_offline,
+        .flags = IRQCHIP_ONOFFLINE_ENABLED,
+};
+
+static void __init irq_pci_init(void)
+{
+        int i, stride;
+        u32 num_bits;
+
+        mips_irq_chip = ioremap(0x1e010000, 4096);
+
+        num_bits = __raw_readl(mips_irq_chip + MIPS_IRQ_CHIP_NUM_BITS);
+        stride = 8 * (1 + ((num_bits - 1) / 64));
+
+
+        pr_notice("mips_irq_chip: %u bits, reg stride: %d\n", num_bits, stride);
+        mips_irq_chip_reg_raw           = MIPS_IRQ_CHIP_REGS + 0 * stride;
+        mips_irq_chip_reg_raw_w1s       = MIPS_IRQ_CHIP_REGS + 1 * stride;
+        mips_irq_chip_reg_raw_w1c       = MIPS_IRQ_CHIP_REGS + 2 * stride;
+        mips_irq_chip_reg_src           = MIPS_IRQ_CHIP_REGS + 3 * stride;
+        mips_irq_chip_reg_en            = MIPS_IRQ_CHIP_REGS + 4 * stride;
+        mips_irq_chip_reg_en_w1s        = MIPS_IRQ_CHIP_REGS + 5 * stride;
+        mips_irq_chip_reg_en_w1c        = MIPS_IRQ_CHIP_REGS + 6 * stride;
+        mips_irq_cpu_stride             = stride * 4;
+
+        for (i = 0; i < 4; i++)
+                irq_set_chip_and_handler(i + MIPS_IRQ_PCIA, &irq_chip_pci, handle_level_irq);
+
+        for (i = 0; i < 2; i++)
+                irq_set_chip_and_handler(i + MIPS_IRQ_MBOX0, &irq_chip_mbox, handle_percpu_irq);
+
+
+        set_c0_status(STATUSF_IP2);
+}
+
+static void irq_pci_dispatch(void)
+{
+        unsigned int cpuid = get_ebase_cpunum();
+        u32 en;
+
+        en = __raw_readl(mips_irq_chip + mips_irq_chip_reg_src +
+                        (cpuid * mips_irq_cpu_stride));
+
+        if (!en) {
+                en = __raw_readl(mips_irq_chip + mips_irq_chip_reg_src + (cpuid * mips_irq_cpu_stride) + sizeof(u32));
+                en = (en >> (2 * cpuid)) & 3;
+
+                if (!en)
+                        spurious_interrupt();
+                else
+                        do_IRQ(__ffs(en) + MIPS_IRQ_MBOX0);     /* MBOX type */
+        } else {
+                do_IRQ(__ffs(en));
+        }
+}
+
+
+void __init arch_init_irq(void)
+{
+        irq_init_core();
+        irq_pci_init();
+}
+
+asmlinkage void plat_irq_dispatch(void)
+{
+        unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM;
+        int ip;
+
+        if (unlikely(!pending)) {
+                spurious_interrupt();
+                return;
+        }
+
+        ip = ffs(pending) - 1 - STATUSB_IP0;
+        if (ip == 2)
+                irq_pci_dispatch();
+        else
+                do_IRQ(MIPS_CPU_IRQ_BASE + ip);
+}
diff --git a/arch/mips/paravirt/paravirt-smp.c b/arch/mips/paravirt/paravirt-smp.c
new file mode 100644
index 000000000000..73a123e08c28
--- /dev/null
+++ b/arch/mips/paravirt/paravirt-smp.c
@@ -0,0 +1,148 @@
+/*
+ * 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) 2013 Cavium, Inc.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/cpumask.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+
+#include <asm/mipsregs.h>
+#include <asm/setup.h>
+#include <asm/time.h>
+#include <asm/smp.h>
+
+/*
+ * Writing the sp releases the CPU, so writes must be ordered, gp
+ * first, then sp.
+ */
+unsigned long paravirt_smp_sp[NR_CPUS];
+unsigned long paravirt_smp_gp[NR_CPUS];
+
+static int numcpus = 1;
+
+static int __init set_numcpus(char *str)
+{
+        int newval;
+
+        if (get_option(&str, &newval)) {
+                if (newval < 1 || newval >= NR_CPUS)
+                        goto bad;
+                numcpus = newval;
+                return 0;
+        }
+bad:
+        return -EINVAL;
+}
+early_param("numcpus", set_numcpus);
+
+
+static void paravirt_smp_setup(void)
+{
+        int id;
+        unsigned int cpunum = get_ebase_cpunum();
+
+        if (WARN_ON(cpunum >= NR_CPUS))
+                return;
+
+        /* 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[cpunum] = 0;
+        __cpu_logical_map[0] = cpunum;
+
+        for (id = 0; id < numcpus; id++) {
+                set_cpu_possible(id, true);
+                set_cpu_present(id, true);
+                __cpu_number_map[id] = id;
+                __cpu_logical_map[id] = id;
+        }
+}
+
+void irq_mbox_ipi(int cpu, unsigned int actions);
+static void paravirt_send_ipi_single(int cpu, unsigned int action)
+{
+        irq_mbox_ipi(cpu, action);
+}
+
+static void paravirt_send_ipi_mask(const struct cpumask *mask, unsigned int action)
+{
+        unsigned int cpu;
+
+        for_each_cpu_mask(cpu, *mask)
+                paravirt_send_ipi_single(cpu, action);
+}
+
+static void paravirt_init_secondary(void)
+{
+        unsigned int sr;
+
+        sr = set_c0_status(ST0_BEV);
+        write_c0_ebase((u32)ebase);
+
+        sr |= STATUSF_IP2; /* Interrupt controller on IP2 */
+        write_c0_status(sr);
+
+        irq_cpu_online();
+}
+
+static void paravirt_smp_finish(void)
+{
+        /* to generate the first CPU timer interrupt */
+        write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);
+        local_irq_enable();
+}
+
+static void paravirt_cpus_done(void)
+{
+}
+
+static void paravirt_boot_secondary(int cpu, struct task_struct *idle)
+{
+        paravirt_smp_gp[cpu] = (unsigned long)task_thread_info(idle);
+        smp_wmb();
+        paravirt_smp_sp[cpu] = __KSTK_TOS(idle);
+}
+
+static irqreturn_t paravirt_reched_interrupt(int irq, void *dev_id)
+{
+        scheduler_ipi();
+        return IRQ_HANDLED;
+}
+
+static irqreturn_t paravirt_function_interrupt(int irq, void *dev_id)
+{
+        smp_call_function_interrupt();
+        return IRQ_HANDLED;
+}
+
+static void paravirt_prepare_cpus(unsigned int max_cpus)
+{
+        if (request_irq(MIPS_IRQ_MBOX0, paravirt_reched_interrupt,
+                        IRQF_PERCPU | IRQF_NO_THREAD, "Scheduler",
+                        paravirt_reched_interrupt)) {
+                panic("Cannot request_irq for SchedulerIPI");
+        }
+        if (request_irq(MIPS_IRQ_MBOX1, paravirt_function_interrupt,
+                        IRQF_PERCPU | IRQF_NO_THREAD, "SMP-Call",
+                        paravirt_function_interrupt)) {
+                panic("Cannot request_irq for SMP-Call");
+        }
+}
+
+struct plat_smp_ops paravirt_smp_ops = {
+        .send_ipi_single        = paravirt_send_ipi_single,
+        .send_ipi_mask          = paravirt_send_ipi_mask,
+        .init_secondary         = paravirt_init_secondary,
+        .smp_finish             = paravirt_smp_finish,
+        .cpus_done              = paravirt_cpus_done,
+        .boot_secondary         = paravirt_boot_secondary,
+        .smp_setup              = paravirt_smp_setup,
+        .prepare_cpus           = paravirt_prepare_cpus,
+};
diff --git a/arch/mips/paravirt/serial.c b/arch/mips/paravirt/serial.c
new file mode 100644
index 000000000000..02b665c02272
--- /dev/null
+++ b/arch/mips/paravirt/serial.c
@@ -0,0 +1,40 @@
+/*
+ * 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) 2013 Cavium, Inc.
+ */
+
+#include <linux/kernel.h>
+#include <linux/virtio_console.h>
+#include <linux/kvm_para.h>
+
+/*
+ * Emit one character to the boot console.
+ */
+int prom_putchar(char c)
+{
+        kvm_hypercall3(KVM_HC_MIPS_CONSOLE_OUTPUT, 0 /*  port 0 */,
+                (unsigned long)&c, 1 /* len == 1 */);
+
+        return 1;
+}
+
+#ifdef CONFIG_VIRTIO_CONSOLE
+static int paravirt_put_chars(u32 vtermno, const char *buf, int count)
+{
+        kvm_hypercall3(KVM_HC_MIPS_CONSOLE_OUTPUT, vtermno,
+                (unsigned long)buf, count);
+
+        return count;
+}
+
+static int __init paravirt_cons_init(void)
+{
+        virtio_cons_early_init(paravirt_put_chars);
+        return 0;
+}
+core_initcall(paravirt_cons_init);
+
+#endif
diff --git a/arch/mips/paravirt/setup.c b/arch/mips/paravirt/setup.c
new file mode 100644
index 000000000000..cb8448b373a7
--- /dev/null
+++ b/arch/mips/paravirt/setup.c
@@ -0,0 +1,67 @@
+/*
+ * 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) 2013 Cavium, Inc.
+ */
+
+#include <linux/kernel.h>
+#include <linux/kvm_para.h>
+
+#include <asm/reboot.h>
+#include <asm/bootinfo.h>
+#include <asm/smp-ops.h>
+#include <asm/time.h>
+
+extern struct plat_smp_ops paravirt_smp_ops;
+
+const char *get_system_type(void)
+{
+        return "MIPS Para-Virtualized Guest";
+}
+
+void __init plat_time_init(void)
+{
+        mips_hpt_frequency = kvm_hypercall0(KVM_HC_MIPS_GET_CLOCK_FREQ);
+
+        preset_lpj = mips_hpt_frequency / (2 * HZ);
+}
+
+static void pv_machine_halt(void)
+{
+        kvm_hypercall0(KVM_HC_MIPS_EXIT_VM);
+}
+
+/*
+ * Early entry point for arch setup
+ */
+void __init prom_init(void)
+{
+        int i;
+        int argc = fw_arg0;
+        char **argv = (char **)fw_arg1;
+
+#ifdef CONFIG_32BIT
+        set_io_port_base(KSEG1ADDR(0x1e000000));
+#else /* CONFIG_64BIT */
+        set_io_port_base(PHYS_TO_XKSEG_UNCACHED(0x1e000000));
+#endif
+
+        for (i = 0; i < argc; i++) {
+                strlcat(arcs_cmdline, argv[i], COMMAND_LINE_SIZE);
+                if (i < argc - 1)
+                        strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
+        }
+        _machine_halt = pv_machine_halt;
+        register_smp_ops(&paravirt_smp_ops);
+}
+
+void __init plat_mem_setup(void)
+{
+        /* Do nothing, the "mem=???" parser handles our memory. */
+}
+
+void __init prom_free_prom_memory(void)
+{
+}