hw/riscv: virt: Allow creating multiple NUMA sockets

We extend RISC-V virt machine to allow creating a multi-socket
machine. Each RISC-V virt machine socket is a NUMA node having
a set of HARTs, a memory instance, a CLINT instance, and a PLIC
instance. Other devices are shared between all sockets. We also
update the generated device tree accordingly.

By default, NUMA multi-socket support is disabled for RISC-V virt
machine. To enable it, users can use "-numa" command-line options
of QEMU.

Example1: For two NUMA nodes with 2 CPUs each, append following
to command-line options: "-smp 4 -numa node -numa node"

Example2: For two NUMA nodes with 1 and 3 CPUs, append following
to command-line options:
"-smp 4 -numa node -numa node -numa cpu,node-id=0,core-id=0 \
-numa cpu,node-id=1,core-id=1 -numa cpu,node-id=1,core-id=2 \
-numa cpu,node-id=1,core-id=3"

The maximum number of sockets in a RISC-V virt machine is 8
but this limit can be changed in future.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Message-Id: <20200616032229.766089-6-anup.patel@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

1 files changed, 7 insertions, 2 deletions

diff --git a/include/hw/riscv/virt.h b/include/hw/riscv/virt.h
index e69355e..1beacd7 100644
--- a/include/hw/riscv/virt.h
+++ b/include/hw/riscv/virt.h
@@ -23,6 +23,9 @@
 #include "hw/sysbus.h"
 #include "hw/block/flash.h"
 
+#define VIRT_CPUS_MAX 8
+#define VIRT_SOCKETS_MAX 8
+
 #define TYPE_RISCV_VIRT_MACHINE MACHINE_TYPE_NAME("virt")
 #define RISCV_VIRT_MACHINE(obj) \
     OBJECT_CHECK(RISCVVirtState, (obj), TYPE_RISCV_VIRT_MACHINE)
@@ -32,8 +35,8 @@ typedef struct {
     MachineState parent;
 
     /*< public >*/
-    RISCVHartArrayState soc;
-    DeviceState *plic;
+    RISCVHartArrayState soc[VIRT_SOCKETS_MAX];
+    DeviceState *plic[VIRT_SOCKETS_MAX];
     PFlashCFI01 *flash[2];
 
     void *fdt;
@@ -74,6 +77,8 @@ enum {
 #define VIRT_PLIC_ENABLE_STRIDE 0x80
 #define VIRT_PLIC_CONTEXT_BASE 0x200000
 #define VIRT_PLIC_CONTEXT_STRIDE 0x1000
+#define VIRT_PLIC_SIZE(__num_context) \
+    (VIRT_PLIC_CONTEXT_BASE + (__num_context) * VIRT_PLIC_CONTEXT_STRIDE)
 
 #define FDT_PCI_ADDR_CELLS    3
 #define FDT_PCI_INT_CELLS     1