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-rw-r--r--Documentation/virtual/kvm/api.txt2
-rw-r--r--arch/arm/include/uapi/asm/kvm.h9
-rw-r--r--arch/arm/kvm/coproc.c164
3 files changed, 172 insertions, 3 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 0e2287406464..94f17a30edd3 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -1805,6 +1805,8 @@ ARM 32-bit CP15 registers have the following id bit patterns:
ARM 64-bit CP15 registers have the following id bit patterns:
0x4003 0000 000F <zero:1> <zero:4> <crm:4> <opc1:4> <zero:3>
+ARM CCSIDR registers are demultiplexed by CSSELR value:
+ 0x4002 0000 0011 00 <csselr:8>
4.69 KVM_GET_ONE_REG
diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
index 53f45f146875..71ae27ec0599 100644
--- a/arch/arm/include/uapi/asm/kvm.h
+++ b/arch/arm/include/uapi/asm/kvm.h
@@ -104,6 +104,15 @@ struct kvm_arch_memory_slot {
#define KVM_REG_ARM_CORE (0x0010 << KVM_REG_ARM_COPROC_SHIFT)
#define KVM_REG_ARM_CORE_REG(name) (offsetof(struct kvm_regs, name) / 4)
+/* Some registers need more space to represent values. */
+#define KVM_REG_ARM_DEMUX (0x0011 << KVM_REG_ARM_COPROC_SHIFT)
+#define KVM_REG_ARM_DEMUX_ID_MASK 0x000000000000FF00
+#define KVM_REG_ARM_DEMUX_ID_SHIFT 8
+#define KVM_REG_ARM_DEMUX_ID_CCSIDR (0x00 << KVM_REG_ARM_DEMUX_ID_SHIFT)
+#define KVM_REG_ARM_DEMUX_VAL_MASK 0x00000000000000FF
+#define KVM_REG_ARM_DEMUX_VAL_SHIFT 0
+
+
/* KVM_IRQ_LINE irq field index values */
#define KVM_ARM_IRQ_TYPE_SHIFT 24
#define KVM_ARM_IRQ_TYPE_MASK 0xff
diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
index 95a0f5e5c1fc..1827b643af15 100644
--- a/arch/arm/kvm/coproc.c
+++ b/arch/arm/kvm/coproc.c
@@ -35,6 +35,12 @@
* Co-processor emulation
*****************************************************************************/
+/* 3 bits per cache level, as per CLIDR, but non-existent caches always 0 */
+static u32 cache_levels;
+
+/* CSSELR values; used to index KVM_REG_ARM_DEMUX_ID_CCSIDR */
+#define CSSELR_MAX 12
+
int kvm_handle_cp10_id(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
kvm_inject_undefined(vcpu);
@@ -548,11 +554,113 @@ static int set_invariant_cp15(u64 id, void __user *uaddr)
return 0;
}
+static bool is_valid_cache(u32 val)
+{
+ u32 level, ctype;
+
+ if (val >= CSSELR_MAX)
+ return -ENOENT;
+
+ /* Bottom bit is Instruction or Data bit. Next 3 bits are level. */
+ level = (val >> 1);
+ ctype = (cache_levels >> (level * 3)) & 7;
+
+ switch (ctype) {
+ case 0: /* No cache */
+ return false;
+ case 1: /* Instruction cache only */
+ return (val & 1);
+ case 2: /* Data cache only */
+ case 4: /* Unified cache */
+ return !(val & 1);
+ case 3: /* Separate instruction and data caches */
+ return true;
+ default: /* Reserved: we can't know instruction or data. */
+ return false;
+ }
+}
+
+/* Which cache CCSIDR represents depends on CSSELR value. */
+static u32 get_ccsidr(u32 csselr)
+{
+ u32 ccsidr;
+
+ /* Make sure noone else changes CSSELR during this! */
+ local_irq_disable();
+ /* Put value into CSSELR */
+ asm volatile("mcr p15, 2, %0, c0, c0, 0" : : "r" (csselr));
+ isb();
+ /* Read result out of CCSIDR */
+ asm volatile("mrc p15, 1, %0, c0, c0, 0" : "=r" (ccsidr));
+ local_irq_enable();
+
+ return ccsidr;
+}
+
+static int demux_c15_get(u64 id, void __user *uaddr)
+{
+ u32 val;
+ u32 __user *uval = uaddr;
+
+ /* Fail if we have unknown bits set. */
+ if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
+ | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
+ return -ENOENT;
+
+ switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
+ case KVM_REG_ARM_DEMUX_ID_CCSIDR:
+ if (KVM_REG_SIZE(id) != 4)
+ return -ENOENT;
+ val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
+ >> KVM_REG_ARM_DEMUX_VAL_SHIFT;
+ if (!is_valid_cache(val))
+ return -ENOENT;
+
+ return put_user(get_ccsidr(val), uval);
+ default:
+ return -ENOENT;
+ }
+}
+
+static int demux_c15_set(u64 id, void __user *uaddr)
+{
+ u32 val, newval;
+ u32 __user *uval = uaddr;
+
+ /* Fail if we have unknown bits set. */
+ if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
+ | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
+ return -ENOENT;
+
+ switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
+ case KVM_REG_ARM_DEMUX_ID_CCSIDR:
+ if (KVM_REG_SIZE(id) != 4)
+ return -ENOENT;
+ val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
+ >> KVM_REG_ARM_DEMUX_VAL_SHIFT;
+ if (!is_valid_cache(val))
+ return -ENOENT;
+
+ if (get_user(newval, uval))
+ return -EFAULT;
+
+ /* This is also invariant: you can't change it. */
+ if (newval != get_ccsidr(val))
+ return -EINVAL;
+ return 0;
+ default:
+ return -ENOENT;
+ }
+}
+
int kvm_arm_coproc_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
const struct coproc_reg *r;
void __user *uaddr = (void __user *)(long)reg->addr;
+ if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
+ return demux_c15_get(reg->id, uaddr);
+
r = index_to_coproc_reg(vcpu, reg->id);
if (!r)
return get_invariant_cp15(reg->id, uaddr);
@@ -566,6 +674,9 @@ int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
const struct coproc_reg *r;
void __user *uaddr = (void __user *)(long)reg->addr;
+ if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
+ return demux_c15_set(reg->id, uaddr);
+
r = index_to_coproc_reg(vcpu, reg->id);
if (!r)
return set_invariant_cp15(reg->id, uaddr);
@@ -574,6 +685,33 @@ int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
return reg_from_user(&vcpu->arch.cp15[r->reg], uaddr, reg->id);
}
+static unsigned int num_demux_regs(void)
+{
+ unsigned int i, count = 0;
+
+ for (i = 0; i < CSSELR_MAX; i++)
+ if (is_valid_cache(i))
+ count++;
+
+ return count;
+}
+
+static int write_demux_regids(u64 __user *uindices)
+{
+ u64 val = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_DEMUX;
+ unsigned int i;
+
+ val |= KVM_REG_ARM_DEMUX_ID_CCSIDR;
+ for (i = 0; i < CSSELR_MAX; i++) {
+ if (!is_valid_cache(i))
+ continue;
+ if (put_user(val | i, uindices))
+ return -EFAULT;
+ uindices++;
+ }
+ return 0;
+}
+
static u64 cp15_to_index(const struct coproc_reg *reg)
{
u64 val = KVM_REG_ARM | (15 << KVM_REG_ARM_COPROC_SHIFT);
@@ -649,6 +787,7 @@ static int walk_cp15(struct kvm_vcpu *vcpu, u64 __user *uind)
unsigned long kvm_arm_num_coproc_regs(struct kvm_vcpu *vcpu)
{
return ARRAY_SIZE(invariant_cp15)
+ + num_demux_regs()
+ walk_cp15(vcpu, (u64 __user *)NULL);
}
@@ -665,9 +804,11 @@ int kvm_arm_copy_coproc_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
}
err = walk_cp15(vcpu, uindices);
- if (err > 0)
- err = 0;
- return err;
+ if (err < 0)
+ return err;
+ uindices += err;
+
+ return write_demux_regids(uindices);
}
void kvm_coproc_table_init(void)
@@ -681,6 +822,23 @@ void kvm_coproc_table_init(void)
/* We abuse the reset function to overwrite the table itself. */
for (i = 0; i < ARRAY_SIZE(invariant_cp15); i++)
invariant_cp15[i].reset(NULL, &invariant_cp15[i]);
+
+ /*
+ * CLIDR format is awkward, so clean it up. See ARM B4.1.20:
+ *
+ * If software reads the Cache Type fields from Ctype1
+ * upwards, once it has seen a value of 0b000, no caches
+ * exist at further-out levels of the hierarchy. So, for
+ * example, if Ctype3 is the first Cache Type field with a
+ * value of 0b000, the values of Ctype4 to Ctype7 must be
+ * ignored.
+ */
+ asm volatile("mrc p15, 1, %0, c0, c0, 1" : "=r" (cache_levels));
+ for (i = 0; i < 7; i++)
+ if (((cache_levels >> (i*3)) & 7) == 0)
+ break;
+ /* Clear all higher bits. */
+ cache_levels &= (1 << (i*3))-1;
}
/**