KVM: ARM: Initial skeleton to compile KVM support

Targets KVM support for Cortex A-15 processors.

Contains all the framework components, make files, header files, some
tracing functionality, and basic user space API.

Only supported core is Cortex-A15 for now.

Most functionality is in arch/arm/kvm/* or arch/arm/include/asm/kvm_*.h.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>

1 files changed, 155 insertions, 0 deletions

diff --git a/arch/arm/kvm/emulate.c b/arch/arm/kvm/emulate.c
new file mode 100644
index 000000000000..3eadc25e95de
--- /dev/null
+++ b/arch/arm/kvm/emulate.c
@@ -0,0 +1,155 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#include <asm/kvm_emulate.h>
+
+#define VCPU_NR_MODES		6
+#define VCPU_REG_OFFSET_USR	0
+#define VCPU_REG_OFFSET_FIQ	1
+#define VCPU_REG_OFFSET_IRQ	2
+#define VCPU_REG_OFFSET_SVC	3
+#define VCPU_REG_OFFSET_ABT	4
+#define VCPU_REG_OFFSET_UND	5
+#define REG_OFFSET(_reg) \
+	(offsetof(struct kvm_regs, _reg) / sizeof(u32))
+
+#define USR_REG_OFFSET(_num) REG_OFFSET(usr_regs.uregs[_num])
+
+static const unsigned long vcpu_reg_offsets[VCPU_NR_MODES][15] = {
+	/* USR/SYS Registers */
+	[VCPU_REG_OFFSET_USR] = {
+		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+		USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
+		USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
+		USR_REG_OFFSET(12), USR_REG_OFFSET(13),	USR_REG_OFFSET(14),
+	},
+
+	/* FIQ Registers */
+	[VCPU_REG_OFFSET_FIQ] = {
+		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+		USR_REG_OFFSET(6), USR_REG_OFFSET(7),
+		REG_OFFSET(fiq_regs[0]), /* r8 */
+		REG_OFFSET(fiq_regs[1]), /* r9 */
+		REG_OFFSET(fiq_regs[2]), /* r10 */
+		REG_OFFSET(fiq_regs[3]), /* r11 */
+		REG_OFFSET(fiq_regs[4]), /* r12 */
+		REG_OFFSET(fiq_regs[5]), /* r13 */
+		REG_OFFSET(fiq_regs[6]), /* r14 */
+	},
+
+	/* IRQ Registers */
+	[VCPU_REG_OFFSET_IRQ] = {
+		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+		USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
+		USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
+		USR_REG_OFFSET(12),
+		REG_OFFSET(irq_regs[0]), /* r13 */
+		REG_OFFSET(irq_regs[1]), /* r14 */
+	},
+
+	/* SVC Registers */
+	[VCPU_REG_OFFSET_SVC] = {
+		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+		USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
+		USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
+		USR_REG_OFFSET(12),
+		REG_OFFSET(svc_regs[0]), /* r13 */
+		REG_OFFSET(svc_regs[1]), /* r14 */
+	},
+
+	/* ABT Registers */
+	[VCPU_REG_OFFSET_ABT] = {
+		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+		USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
+		USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
+		USR_REG_OFFSET(12),
+		REG_OFFSET(abt_regs[0]), /* r13 */
+		REG_OFFSET(abt_regs[1]), /* r14 */
+	},
+
+	/* UND Registers */
+	[VCPU_REG_OFFSET_UND] = {
+		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+		USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
+		USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
+		USR_REG_OFFSET(12),
+		REG_OFFSET(und_regs[0]), /* r13 */
+		REG_OFFSET(und_regs[1]), /* r14 */
+	},
+};
+
+/*
+ * Return a pointer to the register number valid in the current mode of
+ * the virtual CPU.
+ */
+u32 *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num)
+{
+	u32 *reg_array = (u32 *)&vcpu->arch.regs;
+	u32 mode = *vcpu_cpsr(vcpu) & MODE_MASK;
+
+	switch (mode) {
+	case USR_MODE...SVC_MODE:
+		mode &= ~MODE32_BIT; /* 0 ... 3 */
+		break;
+
+	case ABT_MODE:
+		mode = VCPU_REG_OFFSET_ABT;
+		break;
+
+	case UND_MODE:
+		mode = VCPU_REG_OFFSET_UND;
+		break;
+
+	case SYSTEM_MODE:
+		mode = VCPU_REG_OFFSET_USR;
+		break;
+
+	default:
+		BUG();
+	}
+
+	return reg_array + vcpu_reg_offsets[mode][reg_num];
+}
+
+/*
+ * Return the SPSR for the current mode of the virtual CPU.
+ */
+u32 *vcpu_spsr(struct kvm_vcpu *vcpu)
+{
+	u32 mode = *vcpu_cpsr(vcpu) & MODE_MASK;
+	switch (mode) {
+	case SVC_MODE:
+		return &vcpu->arch.regs.KVM_ARM_SVC_spsr;
+	case ABT_MODE:
+		return &vcpu->arch.regs.KVM_ARM_ABT_spsr;
+	case UND_MODE:
+		return &vcpu->arch.regs.KVM_ARM_UND_spsr;
+	case IRQ_MODE:
+		return &vcpu->arch.regs.KVM_ARM_IRQ_spsr;
+	case FIQ_MODE:
+		return &vcpu->arch.regs.KVM_ARM_FIQ_spsr;
+	default:
+		BUG();
+	}
+}