[RFC PATCH v12 qemu 1/2] hw/arm/virt: Basic CXL enablement on pci_expander_bridge instances pxb-cxl

[Jonathan Cameron <Jonathan.Cameron@huawei.com>]

Code based on i386/pc enablement.
The memory layout places space for 16 host bridge register regions after
the GIC_REDIST2 in the extended memmap. Note this is in a hole, so
nothing should move.

The CFMWs are placed above the extended memmap.

Only create the CEDT table if cxl=on set for the machine.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

---
 include/hw/arm/virt.h    |  4 +++
 hw/arm/virt-acpi-build.c | 34 +++++++++++++++++++++++++
 hw/arm/virt.c            | 54 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 92 insertions(+)

diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index c8e94e6aed..3e83d9e06b 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -36,6 +36,7 @@
 #include "hw/arm/boot.h"
 #include "hw/arm/bsa.h"
 #include "hw/block/flash.h"
+#include "hw/cxl/cxl.h"
 #include "system/kvm.h"
 #include "hw/intc/arm_gicv3_common.h"
 #include "qom/object.h"
@@ -85,6 +86,7 @@ enum {
 /* indices of IO regions located after the RAM */
 enum {
     VIRT_HIGH_GIC_REDIST2 =  VIRT_LOWMEMMAP_LAST,
+    VIRT_CXL_HOST,
     VIRT_HIGH_PCIE_ECAM,
     VIRT_HIGH_PCIE_MMIO,
 };
@@ -146,6 +148,7 @@ struct VirtMachineState {
     bool secure;
     bool highmem;
     bool highmem_compact;
+    bool highmem_cxl;
     bool highmem_ecam;
     bool highmem_mmio;
     bool highmem_redists;
@@ -180,6 +183,7 @@ struct VirtMachineState {
     char *oem_id;
     char *oem_table_id;
     bool ns_el2_virt_timer_irq;
+    CXLState cxl_devices_state;
 };
 
 #define VIRT_ECAM_ID(high) (high ? VIRT_HIGH_PCIE_ECAM : VIRT_PCIE_ECAM)
diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 3ac8f8e178..339aa60ce5 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -39,10 +39,12 @@
 #include "hw/acpi/aml-build.h"
 #include "hw/acpi/utils.h"
 #include "hw/acpi/pci.h"
+#include "hw/acpi/cxl.h"
 #include "hw/acpi/memory_hotplug.h"
 #include "hw/acpi/generic_event_device.h"
 #include "hw/acpi/tpm.h"
 #include "hw/acpi/hmat.h"
+#include "hw/cxl/cxl.h"
 #include "hw/pci/pcie_host.h"
 #include "hw/pci/pci.h"
 #include "hw/pci/pci_bus.h"
@@ -119,10 +121,29 @@ static void acpi_dsdt_add_flash(Aml *scope, const MemMapEntry *flash_memmap)
     aml_append(scope, dev);
 }
 
+static void build_acpi0017(Aml *table)
+{
+    Aml *dev, *scope, *method;
+
+    scope =  aml_scope("_SB");
+    dev = aml_device("CXLM");
+    aml_append(dev, aml_name_decl("_HID", aml_string("ACPI0017")));
+
+    method = aml_method("_STA", 0, AML_NOTSERIALIZED);
+    aml_append(method, aml_return(aml_int(0x0B)));
+    aml_append(dev, method);
+    build_cxl_dsm_method(dev);
+
+    aml_append(scope, dev);
+    aml_append(table, scope);
+}
+
 static void acpi_dsdt_add_pci(Aml *scope, const MemMapEntry *memmap,
                               uint32_t irq, VirtMachineState *vms)
 {
     int ecam_id = VIRT_ECAM_ID(vms->highmem_ecam);
+    bool cxl_present = false;
+    PCIBus *bus = vms->bus;
     struct GPEXConfig cfg = {
         .mmio32 = memmap[VIRT_PCIE_MMIO],
         .pio    = memmap[VIRT_PCIE_PIO],
@@ -136,6 +157,14 @@ static void acpi_dsdt_add_pci(Aml *scope, const MemMapEntry *memmap,
     }
 
     acpi_dsdt_add_gpex(scope, &cfg);
+    QLIST_FOREACH(bus, &vms->bus->child, sibling) {
+        if (pci_bus_is_cxl(bus)) {
+            cxl_present = true;
+        }
+    }
+    if (cxl_present) {
+        build_acpi0017(scope);
+    }
 }
 
 static void acpi_dsdt_add_gpio(Aml *scope, const MemMapEntry *gpio_memmap,
@@ -967,6 +996,11 @@ void virt_acpi_build(VirtMachineState *vms, AcpiBuildTables *tables)
         }
     }
 
+    if (vms->cxl_devices_state.is_enabled) {
+        cxl_build_cedt(table_offsets, tables_blob, tables->linker,
+                       vms->oem_id, vms->oem_table_id, &vms->cxl_devices_state);
+    }
+
     if (ms->nvdimms_state->is_enabled) {
         nvdimm_build_acpi(table_offsets, tables_blob, tables->linker,
                           ms->nvdimms_state, ms->ram_slots, vms->oem_id,
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 99e0a68b6c..cc16a5750d 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -56,6 +56,7 @@
 #include "qemu/error-report.h"
 #include "qemu/module.h"
 #include "hw/pci-host/gpex.h"
+#include "hw/pci-bridge/pci_expander_bridge.h"
 #include "hw/virtio/virtio-pci.h"
 #include "hw/core/sysbus-fdt.h"
 #include "hw/platform-bus.h"
@@ -84,6 +85,8 @@
 #include "hw/virtio/virtio-md-pci.h"
 #include "hw/virtio/virtio-iommu.h"
 #include "hw/char/pl011.h"
+#include "hw/cxl/cxl.h"
+#include "hw/cxl/cxl_host.h"
 #include "qemu/guest-random.h"
 
 static GlobalProperty arm_virt_compat[] = {
@@ -211,6 +214,7 @@ static const MemMapEntry base_memmap[] = {
 static MemMapEntry extended_memmap[] = {
     /* Additional 64 MB redist region (can contain up to 512 redistributors) */
     [VIRT_HIGH_GIC_REDIST2] =   { 0x0, 64 * MiB },
+    [VIRT_CXL_HOST] =           { 0x0, 64 * KiB * 16 }, /* 16 UID */
     [VIRT_HIGH_PCIE_ECAM] =     { 0x0, 256 * MiB },
     /* Second PCIe window */
     [VIRT_HIGH_PCIE_MMIO] =     { 0x0, 512 * GiB },
@@ -1615,6 +1619,17 @@ static void create_pcie(VirtMachineState *vms)
     }
 }
 
+static void create_cxl_host_reg_region(VirtMachineState *vms)
+{
+    MemoryRegion *sysmem = get_system_memory();
+    MemoryRegion *mr = &vms->cxl_devices_state.host_mr;
+
+    memory_region_init(mr, OBJECT(vms), "cxl_host_reg",
+                       vms->memmap[VIRT_CXL_HOST].size);
+    memory_region_add_subregion(sysmem, vms->memmap[VIRT_CXL_HOST].base, mr);
+    vms->highmem_cxl = true;
+}
+
 static void create_platform_bus(VirtMachineState *vms)
 {
     DeviceState *dev;
@@ -1733,6 +1748,12 @@ void virt_machine_done(Notifier *notifier, void *data)
     struct arm_boot_info *info = &vms->bootinfo;
     AddressSpace *as = arm_boot_address_space(cpu, info);
 
+    cxl_hook_up_pxb_registers(vms->bus, &vms->cxl_devices_state,
+                              &error_fatal);
+
+    if (vms->cxl_devices_state.is_enabled) {
+        cxl_fmws_link_targets(&vms->cxl_devices_state, &error_fatal);
+    }
     /*
      * If the user provided a dtb, we assume the dynamic sysbus nodes
      * already are integrated there. This corresponds to a use case where
@@ -1785,6 +1806,7 @@ static inline bool *virt_get_high_memmap_enabled(VirtMachineState *vms,
 {
     bool *enabled_array[] = {
         &vms->highmem_redists,
+        &vms->highmem_cxl,
         &vms->highmem_ecam,
         &vms->highmem_mmio,
     };
@@ -1892,6 +1914,27 @@ static void virt_set_memmap(VirtMachineState *vms, int pa_bits)
     if (device_memory_size > 0) {
         machine_memory_devices_init(ms, device_memory_base, device_memory_size);
     }
+
+    if (vms->cxl_devices_state.fixed_windows) {
+        GList *it;
+
+        base = ROUND_UP(vms->highest_gpa + 1, 256 * MiB);
+        for (it = vms->cxl_devices_state.fixed_windows; it; it = it->next) {
+            CXLFixedWindow *fw = it->data;
+
+            if (base + fw->size <= BIT_ULL(pa_bits)) {
+                vms->highest_gpa = base + fw->size - 1;
+            } else {
+                error_report("CFMWS does not fit under PA limit");
+                exit(EXIT_FAILURE);
+            }
+
+            fw->base = base;
+            memory_region_init_io(&fw->mr, OBJECT(vms), &cfmws_ops, fw,
+                                  "cxl-fixed-memory-region", fw->size);
+            base += fw->size;
+        }
+    }
 }
 
 static VirtGICType finalize_gic_version_do(const char *accel_name,
@@ -2346,6 +2389,15 @@ static void machvirt_init(MachineState *machine)
     memory_region_add_subregion(sysmem, vms->memmap[VIRT_MEM].base,
                                 machine->ram);
 
+    if (vms->cxl_devices_state.fixed_windows) {
+        GList *it;
+        for (it = vms->cxl_devices_state.fixed_windows; it; it = it->next) {
+            CXLFixedWindow *fw = it->data;
+
+            memory_region_add_subregion(sysmem, fw->base, &fw->mr);
+        }
+    }
+
     virt_flash_fdt(vms, sysmem, secure_sysmem ?: sysmem);
 
     create_gic(vms, sysmem);
@@ -2401,6 +2453,7 @@ static void machvirt_init(MachineState *machine)
     create_rtc(vms);
 
     create_pcie(vms);
+    create_cxl_host_reg_region(vms);
 
     if (has_ged && aarch64 && firmware_loaded && virt_is_acpi_enabled(vms)) {
         vms->acpi_dev = create_acpi_ged(vms);
@@ -3332,6 +3385,7 @@ static void virt_instance_init(Object *obj)
 
     vms->oem_id = g_strndup(ACPI_BUILD_APPNAME6, 6);
     vms->oem_table_id = g_strndup(ACPI_BUILD_APPNAME8, 8);
+    cxl_machine_init(obj, &vms->cxl_devices_state);
 }
 
 static const TypeInfo virt_machine_info = {
-- 
2.43.0