[RFC PATCH 1/2] hw/arm/sbsa-ref: Enable CXL Host Bridge by pxb-cxl

[Yuquan Wang]

The memory layout places 1M space for 16 host bridge register regions
in the sbsa-ref memmap. In addition, this creates a default pxb-cxl
(bus_nr=0xfe) bridge with one cxl-rp on sbsa-ref.

Signed-off-by: Yuquan Wang <wangyuquan1236@phytium.com.cn>
---
 hw/arm/sbsa-ref.c | 54 ++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 51 insertions(+), 3 deletions(-)

diff --git a/hw/arm/sbsa-ref.c b/hw/arm/sbsa-ref.c
index ae37a92301..dc924d181e 100644
--- a/hw/arm/sbsa-ref.c
+++ b/hw/arm/sbsa-ref.c
@@ -41,7 +41,10 @@
 #include "hw/intc/arm_gicv3_common.h"
 #include "hw/intc/arm_gicv3_its_common.h"
 #include "hw/loader.h"
+#include "hw/pci/pci_bridge.h"
+#include "hw/pci/pci_bus.h"
 #include "hw/pci-host/gpex.h"
+#include "hw/pci-bridge/pci_expander_bridge.h"
 #include "hw/qdev-properties.h"
 #include "hw/usb.h"
 #include "hw/usb/xhci.h"
@@ -52,6 +55,8 @@
 #include "qom/object.h"
 #include "target/arm/cpu-qom.h"
 #include "target/arm/gtimer.h"
+#include "hw/cxl/cxl.h"
+#include "hw/cxl/cxl_host.h"
 
 #define RAMLIMIT_GB 8192
 #define RAMLIMIT_BYTES (RAMLIMIT_GB * GiB)
@@ -94,6 +99,7 @@ enum {
     SBSA_SECURE_MEM,
     SBSA_AHCI,
     SBSA_XHCI,
+    SBSA_CXL_HOST,
 };
 
 struct SBSAMachineState {
@@ -105,6 +111,9 @@ struct SBSAMachineState {
     int psci_conduit;
     DeviceState *gic;
     PFlashCFI01 *flash[2];
+    CXLState cxl_devices_state;
+    PCIBus *bus;
+    PCIBus *cxlbus;
 };
 
 #define TYPE_SBSA_MACHINE   MACHINE_TYPE_NAME("sbsa-ref")
@@ -132,6 +141,8 @@ static const MemMapEntry sbsa_ref_memmap[] = {
     /* Space here reserved for more SMMUs */
     [SBSA_AHCI] =               { 0x60100000, 0x00010000 },
     [SBSA_XHCI] =               { 0x60110000, 0x00010000 },
+    /* 1M CXL Host Bridge Registers space (64KiB * 16) */
+    [SBSA_CXL_HOST] =           { 0x60120000, 0x00100000 },
     /* Space here reserved for other devices */
     [SBSA_PCIE_PIO] =           { 0x7fff0000, 0x00010000 },
     /* 32-bit address PCIE MMIO space */
@@ -631,6 +642,26 @@ static void create_smmu(const SBSAMachineState *sms, 
PCIBus *bus)
     }
 }
 
+static void create_pxb_cxl(SBSAMachineState *sms)
+{
+    CXLHost *host;
+    PCIHostState *cxl;
+
+    sms->cxl_devices_state.is_enabled = true;
+
+    DeviceState *qdev;
+    qdev = qdev_new(TYPE_PXB_CXL_DEV);
+    qdev_prop_set_uint32(qdev, "bus_nr", 0xfe);
+
+    PCIDevice *dev = PCI_DEVICE(qdev);
+    pci_realize_and_unref(dev, sms->bus, &error_fatal);
+
+    host = PXB_CXL_DEV(dev)->cxl_host_bridge;
+    cxl = PCI_HOST_BRIDGE(host);
+    sms->cxlbus = cxl->bus;
+    pci_create_simple(sms->cxlbus, -1, "cxl-rp");
+}
+
 static void create_pcie(SBSAMachineState *sms)
 {
     hwaddr base_ecam = sbsa_ref_memmap[SBSA_PCIE_ECAM].base;
@@ -682,12 +713,25 @@ static void create_pcie(SBSAMachineState *sms)
     }
 
     pci = PCI_HOST_BRIDGE(dev);
+    sms->bus = pci->bus;
+
+    pci_init_nic_devices(sms->bus, mc->default_nic);
 
-    pci_init_nic_devices(pci->bus, mc->default_nic);
+    pci_create_simple(sms->bus, -1, "bochs-display");
 
-    pci_create_simple(pci->bus, -1, "bochs-display");
+    create_smmu(sms, sms->bus);
 
-    create_smmu(sms, pci->bus);
+    create_pxb_cxl(sms);
+}
+
+static void create_cxl_host_reg_region(SBSAMachineState *sms)
+{
+    MemoryRegion *sysmem = get_system_memory();
+    MemoryRegion *mr = &sms->cxl_devices_state.host_mr;
+
+    memory_region_init(mr, OBJECT(sms), "cxl_host_reg",
+                       sbsa_ref_memmap[SBSA_CXL_HOST].size);
+    memory_region_add_subregion(sysmem, sbsa_ref_memmap[SBSA_CXL_HOST].base, 
mr);
 }
 
 static void *sbsa_ref_dtb(const struct arm_boot_info *binfo, int *fdt_size)
@@ -823,6 +867,10 @@ static void sbsa_ref_init(MachineState *machine)
 
     create_pcie(sms);
 
+    create_cxl_host_reg_region(sms);
+
+    cxl_hook_up_pxb_registers(sms->bus, &sms->cxl_devices_state, &error_fatal);
+
     create_secure_ec(secure_sysmem);
 
     sms->bootinfo.ram_size = machine->ram_size;
-- 
2.34.1