On LoongArch system, ipi hw uses iocsr registers, there is one iocsr
register access on ipi sender and two iocsr access on ipi interrupt
handler. On VM mode all iocsr registers accessing will trap into
hypervisor.
This patch adds pv ipi support for VM, hypercall instruction is used
to ipi sender, and hypervisor will inject SWI on the VM. During SWI
interrupt handler, only estat CSR register is read and written. Estat
CSR register access will not trap into hypervisor. So with pv ipi
supported, pv ipi sender will trap into hypervsor, pv ipi interrupt
handler will not trap.
Also this patch adds ipi multicast support, the method is similar with
x86. With ipi multicast support, ipi notification can be sent to at most
64 vcpus at a time. And hw cpuid is equal to logic cpuid in LoongArch
kvm hypervisor now, will add hw cpuid search logic in kvm hypervisor
in the next patch.
Signed-off-by: Bibo Mao
---
arch/loongarch/include/asm/hardirq.h | 1 +
arch/loongarch/include/asm/kvm_para.h | 124 +
arch/loongarch/include/asm/loongarch.h | 1 +
arch/loongarch/kernel/irq.c| 2 +-
arch/loongarch/kernel/paravirt.c | 103
arch/loongarch/kernel/smp.c| 2 +-
arch/loongarch/kvm/exit.c | 66 -
7 files changed, 295 insertions(+), 4 deletions(-)
diff --git a/arch/loongarch/include/asm/hardirq.h
b/arch/loongarch/include/asm/hardirq.h
index 9f0038e19c7f..998011f162d0 100644
--- a/arch/loongarch/include/asm/hardirq.h
+++ b/arch/loongarch/include/asm/hardirq.h
@@ -21,6 +21,7 @@ enum ipi_msg_type {
typedef struct {
unsigned int ipi_irqs[NR_IPI];
unsigned int __softirq_pending;
+ atomic_t messages;
} cacheline_aligned irq_cpustat_t;
DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
diff --git a/arch/loongarch/include/asm/kvm_para.h
b/arch/loongarch/include/asm/kvm_para.h
index 41200e922a82..a25a84e372b9 100644
--- a/arch/loongarch/include/asm/kvm_para.h
+++ b/arch/loongarch/include/asm/kvm_para.h
@@ -9,6 +9,10 @@
#define HYPERVISOR_VENDOR_SHIFT8
#define HYPERCALL_CODE(vendor, code) ((vendor << HYPERVISOR_VENDOR_SHIFT) +
code)
+#define KVM_HC_CODE_SERVICE0
+#define KVM_HC_SERVICE HYPERCALL_CODE(HYPERVISOR_KVM,
KVM_HC_CODE_SERVICE)
+#define KVM_HC_FUNC_IPI 1
+
/*
* LoongArch hypcall return code
*/
@@ -16,6 +20,126 @@
#define KVM_HC_INVALID_CODE-1UL
#define KVM_HC_INVALID_PARAMETER -2UL
+/*
+ * Hypercalls interface for KVM hypervisor
+ *
+ * a0: function identifier
+ * a1-a6: args
+ * Return value will be placed in v0.
+ * Up to 6 arguments are passed in a1, a2, a3, a4, a5, a6.
+ */
+static __always_inline long kvm_hypercall(u64 fid)
+{
+ register long ret asm("v0");
+ register unsigned long fun asm("a0") = fid;
+
+ __asm__ __volatile__(
+ "hvcl "__stringify(KVM_HC_SERVICE)
+ : "=r" (ret)
+ : "r" (fun)
+ : "memory"
+ );
+
+ return ret;
+}
+
+static __always_inline long kvm_hypercall1(u64 fid, unsigned long arg0)
+{
+ register long ret asm("v0");
+ register unsigned long fun asm("a0") = fid;
+ register unsigned long a1 asm("a1") = arg0;
+
+ __asm__ __volatile__(
+ "hvcl "__stringify(KVM_HC_SERVICE)
+ : "=r" (ret)
+ : "r" (fun), "r" (a1)
+ : "memory"
+ );
+
+ return ret;
+}
+
+static __always_inline long kvm_hypercall2(u64 fid,
+ unsigned long arg0, unsigned long arg1)
+{
+ register long ret asm("v0");
+ register unsigned long fun asm("a0") = fid;
+ register unsigned long a1 asm("a1") = arg0;
+ register unsigned long a2 asm("a2") = arg1;
+
+ __asm__ __volatile__(
+ "hvcl "__stringify(KVM_HC_SERVICE)
+ : "=r" (ret)
+ : "r" (fun), "r" (a1), "r" (a2)
+ : "memory"
+ );
+
+ return ret;
+}
+
+static __always_inline long kvm_hypercall3(u64 fid,
+ unsigned long arg0, unsigned long arg1, unsigned long arg2)
+{
+ register long ret asm("v0");
+ register unsigned long fun asm("a0") = fid;
+ register unsigned long a1 asm("a1") = arg0;
+ register unsigned long a2 asm("a2") = arg1;
+ register unsigned long a3 asm("a3") = arg2;
+
+ __asm__ __volatile__(
+ "hvcl "__stringify(KVM_HC_SERVICE)
+ : "=r" (ret)
+ : "r" (fun), "r" (a1), "r" (a2), "r" (a3)
+ : "memory"
+ );
+
+ return ret;
+}
+
+static __always_inline long kvm_hypercall4(u64 fid,
+ unsigned long arg0, unsigned long arg1, unsigned long arg2,
+ unsigned long arg3)
+{
+ register long ret asm("v0");
+ register unsigned long fun asm("a0") = fid;
+
