Wire the initial in-kernel MMIO support code for the VGIC, used
for the distributor emulation.
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
arch/arm/include/asm/kvm_vgic.h | 4 +-
arch/arm/kvm/Makefile | 1 +
arch/arm/kvm/vgic.c | 130 +++++++++++++++++++++++++++++++++++++++
3 files changed, 134 insertions(+), 1 deletions(-)
create mode 100644 arch/arm/kvm/vgic.c
diff --git a/arch/arm/include/asm/kvm_vgic.h b/arch/arm/include/asm/kvm_vgic.h
index 222812e..34f5cc0 100644
--- a/arch/arm/include/asm/kvm_vgic.h
+++ b/arch/arm/include/asm/kvm_vgic.h
@@ -11,7 +11,9 @@ struct kvm;
struct kvm_vcpu;
struct kvm_run;
-#ifndef CONFIG_KVM_ARM_VGIC
+#ifdef CONFIG_KVM_ARM_VGIC
+int vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run);
+#else
static inline int kvm_vgic_hyp_init(void)
{
return 0;
diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile
index e69a8e1..d21c7b7 100644
--- a/arch/arm/kvm/Makefile
+++ b/arch/arm/kvm/Makefile
@@ -15,3 +15,4 @@ kvm-arm-y += $(addprefix ../../../virt/kvm/, kvm_main.o coalesced_mmio.o)
kvm-arm-y += arm.o guest.o mmu.o emulate.o
obj-$(CONFIG_KVM) += kvm-arm.o
+obj-$(CONFIG_KVM_ARM_VGIC) += vgic.o
diff --git a/arch/arm/kvm/vgic.c b/arch/arm/kvm/vgic.c
new file mode 100644
index 0000000..f7856a9
--- /dev/null
+++ b/arch/arm/kvm/vgic.c
@@ -0,0 +1,130 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier at arm.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, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+
+#define ACCESS_READ_VALUE (1 << 0)
+#define ACCESS_READ_RAZ (0 << 0)
+#define ACCESS_READ_MASK(x) ((x) & (1 << 0))
+#define ACCESS_WRITE_IGNORED (0 << 1)
+#define ACCESS_WRITE_SETBIT (1 << 1)
+#define ACCESS_WRITE_CLEARBIT (2 << 1)
+#define ACCESS_WRITE_VALUE (3 << 1)
+#define ACCESS_WRITE_MASK(x) ((x) & (3 << 1))
+
+static void mmio_do_copy(struct kvm_run *run, u32 *reg, u32 offset, int mode)
+{
+ int u32off = offset & 3;
+ int shift = u32off * 8;
+ u32 mask;
+ u32 regval;
+
+ /*
+ * We do silly things on cross-register accesses, so pretend
+ * they do not exist. Will have to be handled though...
+ */
+ if (WARN_ON((u32off + run->mmio.len) > 4))
+ run->mmio.len = 4 - u32off;
+
+ mask = ((u32)-1) >> (u32off * 8);
+ if (reg)
+ regval = *reg;
+ else {
+ BUG_ON(mode != (ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED));
+ regval = 0;
+ }
+
+ if (run->mmio.is_write) {
+ u32 data = (*((u32 *)run->mmio.data) & mask) << shift;
+ switch (ACCESS_WRITE_MASK(mode)) {
+ case ACCESS_WRITE_IGNORED:
+ return;
+
+ case ACCESS_WRITE_SETBIT:
+ regval |= data;
+ break;
+
+ case ACCESS_WRITE_CLEARBIT:
+ regval &= ~data;
+ break;
+
+ case ACCESS_WRITE_VALUE:
+ regval = (regval & ~(mask << shift)) | data;
+ break;
+ }
+ *reg = regval;
+ } else {
+ switch (ACCESS_READ_MASK(mode)) {
+ case ACCESS_READ_RAZ:
+ regval = 0;
+ /* fall through */
+
+ case ACCESS_READ_VALUE:
+ *((u32 *)run->mmio.data) = (regval >> shift) & mask;
+ }
+ }
+}
+
+/* All this should really be generic code... FIXME!!! */
+struct mmio_range {
+ unsigned long base;
+ unsigned long len;
+ void (*handle_mmio)(struct kvm_vcpu *vcpu, struct kvm_run *run,
+ u32 offset);
+};
+
+static const struct mmio_range vgic_ranges[] = {
+ {}
+};
+
+static const
+struct mmio_range *find_matching_range(const struct mmio_range *ranges,
+ struct kvm_run *run)
+{
+ const struct mmio_range *r = ranges;
+ while (r->len) {
+ if (run->mmio.phys_addr >= r->base &&
+ (run->mmio.phys_addr + run->mmio.len) <= (r->base + r->len))
+ return r;
+ r++;
+ }
+
+ return NULL;
+}
+
+int vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ const struct mmio_range *range;
+
+ if (!irqchip_in_kernel(vcpu->kvm))
+ return KVM_EXIT_MMIO;
+
+ range = find_matching_range(vgic_ranges, run);
+ if (!range || !range->handle_mmio)
+ return KVM_EXIT_MMIO;
+
+ pr_debug("emulating %d %08llx %d\n", run->mmio.is_write,
+ run->mmio.phys_addr, run->mmio.len);
+ range->handle_mmio(vcpu, run, run->mmio.phys_addr - range->base);
+ kvm_handle_mmio_return(vcpu, run);
+
+ return KVM_EXIT_UNKNOWN;
+}
--
1.7.7.1
