hw/cxl: Make the CXL fixed memory window setup a machine parameter.

Paolo Bonzini requested this change to simplify the ongoing
effort to allow machine setup entirely via RPC.

Includes shortening the command line form cxl-fixed-memory-window
to cxl-fmw as the command lines are extremely long even with this
change.

The json change is needed to ensure that there is
a CXLFixedMemoryWindowOptionsList even though the actual
element in the json is never used. Similar to existing
SgxEpcProperties.

Update qemu-options.hx to reflect that this is now a -machine
parameter.  The bulk of -M / -machine parameters are documented
under machine, so use that in preference to M.

Update cxl-test and bios-tables-test to reflect new parameters.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Message-Id: <20220608145440.26106-2-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

docs/system/devices/cxl.rst

@@ -251,7 +251,7 @@ A very simple setup with just one directly attached CXL Type 3 device::
   -device pxb-cxl,bus_nr=12,bus=pcie.0,id=cxl.1 \
   -device cxl-rp,port=0,bus=cxl.1,id=root_port13,chassis=0,slot=2 \
   -device cxl-type3,bus=root_port13,memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem0 \
-  -cxl-fixed-memory-window targets.0=cxl.1,size=4G
+  -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.size=4G
 
 A setup suitable for 4 way interleave. Only one fixed window provided, to enable 2 way
 interleave across 2 CXL host bridges.  Each host bridge has 2 CXL Root Ports, with
@@ -277,7 +277,7 @@ the CXL Type3 device directly attached (no switches).::
   -device cxl-type3,bus=root_port15,memdev=cxl-mem3,lsa=cxl-lsa3,id=cxl-pmem2 \
   -device cxl-rp,port=1,bus=cxl.2,id=root_port16,chassis=0,slot=6 \
   -device cxl-type3,bus=root_port16,memdev=cxl-mem4,lsa=cxl-lsa4,id=cxl-pmem3 \
-  -cxl-fixed-memory-window targets.0=cxl.1,targets.1=cxl.2,size=4G,interleave-granularity=8k
+  -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.targets.1=cxl.2,cxl-fmw.0.size=4G,cxl-fmw.0.interleave-granularity=8k
 
 Kernel Configuration Options
 ----------------------------

hw/core/machine.c

@@ -629,20 +629,6 @@ static void machine_set_nvdimm_persistence(Object *obj, const char *value,
     nvdimms_state->persistence_string = g_strdup(value);
 }
 
-static bool machine_get_cxl(Object *obj, Error **errp)
-{
-    MachineState *ms = MACHINE(obj);
-
-    return ms->cxl_devices_state->is_enabled;
-}
-
-static void machine_set_cxl(Object *obj, bool value, Error **errp)
-{
-    MachineState *ms = MACHINE(obj);
-
-    ms->cxl_devices_state->is_enabled = value;
-}
-
 void machine_class_allow_dynamic_sysbus_dev(MachineClass *mc, const char *type)
 {
     QAPI_LIST_PREPEND(mc->allowed_dynamic_sysbus_devices, g_strdup(type));
@@ -929,8 +915,6 @@ static void machine_class_init(ObjectClass *oc, void *data)
     mc->default_ram_size = 128 * MiB;
     mc->rom_file_has_mr = true;
 
-    /* Few machines support CXL, so default to off */
-    mc->cxl_supported = false;
     /* numa node memory size aligned on 8MB by default.
      * On Linux, each node's border has to be 8MB aligned
      */
@@ -1092,13 +1076,7 @@ static void machine_initfn(Object *obj)
     }
 
     if (mc->cxl_supported) {
-        Object *obj = OBJECT(ms);
-
         ms->cxl_devices_state = g_new0(CXLState, 1);
-        object_property_add_bool(obj, "cxl", machine_get_cxl, machine_set_cxl);
-        object_property_set_description(obj, "cxl",
-                                        "Set on/off to enable/disable "
-                                        "CXL instantiation");
     }
 
     if (mc->cpu_index_to_instance_props && mc->get_default_cpu_node_id) {

hw/cxl/cxl-host-stubs.c

@@ -6,11 +6,9 @@
 #include "qemu/osdep.h"
 #include "qapi/error.h"
 #include "hw/cxl/cxl.h"
-
-void cxl_fixed_memory_window_config(MachineState *ms,
-                                    CXLFixedMemoryWindowOptions *object,
-                                    Error **errp) {};
+#include "hw/cxl/cxl_host.h"
 
 void cxl_fixed_memory_window_link_targets(Error **errp) {};
+void cxl_machine_init(Object *obj, CXLState *state) {};
 
 const MemoryRegionOps cfmws_ops;

hw/cxl/cxl-host.c

@@ -15,14 +15,15 @@
 
 #include "qapi/qapi-visit-machine.h"
 #include "hw/cxl/cxl.h"
+#include "hw/cxl/cxl_host.h"
 #include "hw/pci/pci_bus.h"
 #include "hw/pci/pci_bridge.h"
 #include "hw/pci/pci_host.h"
 #include "hw/pci/pcie_port.h"
 
-void cxl_fixed_memory_window_config(MachineState *ms,
-                                    CXLFixedMemoryWindowOptions *object,
-                                    Error **errp)
+static void cxl_fixed_memory_window_config(CXLState *cxl_state,
+                                           CXLFixedMemoryWindowOptions *object,
+                                           Error **errp)
 {
     CXLFixedWindow *fw = g_malloc0(sizeof(*fw));
     strList *target;
@@ -62,8 +63,7 @@ void cxl_fixed_memory_window_config(MachineState *ms,
         fw->enc_int_gran = 0;
     }
 
-    ms->cxl_devices_state->fixed_windows =
-        g_list_append(ms->cxl_devices_state->fixed_windows, fw);
+    cxl_state->fixed_windows = g_list_append(cxl_state->fixed_windows, fw);
 
     return;
 }
@@ -220,3 +220,65 @@ const MemoryRegionOps cfmws_ops = {
         .unaligned = true,
     },
 };
+
+static void machine_get_cxl(Object *obj, Visitor *v, const char *name,
+                            void *opaque, Error **errp)
+{
+    CXLState *cxl_state = opaque;
+    bool value = cxl_state->is_enabled;
+
+    visit_type_bool(v, name, &value, errp);
+}
+
+static void machine_set_cxl(Object *obj, Visitor *v, const char *name,
+                            void *opaque, Error **errp)
+{
+    CXLState *cxl_state = opaque;
+    bool value;
+
+    if (!visit_type_bool(v, name, &value, errp)) {
+        return;
+    }
+    cxl_state->is_enabled = value;
+}
+
+static void machine_get_cfmw(Object *obj, Visitor *v, const char *name,
+                             void *opaque, Error **errp)
+{
+    CXLFixedMemoryWindowOptionsList **list = opaque;
+
+    visit_type_CXLFixedMemoryWindowOptionsList(v, name, list, errp);
+}
+
+static void machine_set_cfmw(Object *obj, Visitor *v, const char *name,
+                             void *opaque, Error **errp)
+{
+    CXLState *state = opaque;
+    CXLFixedMemoryWindowOptionsList *cfmw_list = NULL;
+    CXLFixedMemoryWindowOptionsList *it;
+
+    visit_type_CXLFixedMemoryWindowOptionsList(v, name, &cfmw_list, errp);
+    if (!cfmw_list) {
+        return;
+    }
+
+    for (it = cfmw_list; it; it = it->next) {
+        cxl_fixed_memory_window_config(state, it->value, errp);
+    }
+    state->cfmw_list = cfmw_list;
+}
+
+void cxl_machine_init(Object *obj, CXLState *state)
+{
+    object_property_add(obj, "cxl", "bool", machine_get_cxl,
+                        machine_set_cxl, NULL, state);
+    object_property_set_description(obj, "cxl",
+                                    "Set on/off to enable/disable "
+                                    "CXL instantiation");
+
+    object_property_add(obj, "cxl-fmw", "CXLFixedMemoryWindow",
+                        machine_get_cfmw, machine_set_cfmw,
+                        NULL, state);
+    object_property_set_description(obj, "cxl-fmw",
+                                    "CXL Fixed Memory Windows (array)");
+}

hw/i386/pc.c

@@ -76,6 +76,7 @@
 #include "hw/mem/pc-dimm.h"
 #include "hw/mem/nvdimm.h"
 #include "hw/cxl/cxl.h"
+#include "hw/cxl/cxl_host.h"
 #include "qapi/error.h"
 #include "qapi/qapi-visit-common.h"
 #include "qapi/qapi-visit-machine.h"
@@ -1682,6 +1683,7 @@ static void pc_machine_set_max_fw_size(Object *obj, Visitor *v,
 static void pc_machine_initfn(Object *obj)
 {
     PCMachineState *pcms = PC_MACHINE(obj);
+    MachineState *ms = MACHINE(obj);
 
 #ifdef CONFIG_VMPORT
     pcms->vmport = ON_OFF_AUTO_AUTO;
@@ -1706,6 +1708,7 @@ static void pc_machine_initfn(Object *obj)
     pcms->pcspk = isa_new(TYPE_PC_SPEAKER);
     object_property_add_alias(OBJECT(pcms), "pcspk-audiodev",
                               OBJECT(pcms->pcspk), "audiodev");
+    cxl_machine_init(obj, ms->cxl_devices_state);
 }
 
 static void pc_machine_reset(MachineState *machine)

hw/pci-bridge/pci_expander_bridge.c

@@ -468,7 +468,7 @@ static void pxb_cxl_dev_realize(PCIDevice *dev, Error **errp)
         error_setg(errp, "pxb-cxl devices cannot reside on a PCI bus");
         return;
     }
-    if (!ms->cxl_devices_state->is_enabled) {
+    if (!ms->cxl_devices_state || !ms->cxl_devices_state->is_enabled) {
         error_setg(errp, "Machine does not have cxl=on");
         return;
     }

include/hw/boards.h

@@ -362,6 +362,7 @@ struct MachineState {
     struct NVDIMMState *nvdimms_state;
     struct CXLState *cxl_devices_state;
     struct NumaState *numa_state;
+    CXLFixedMemoryWindowOptionsList *cfmws_list;
 };
 
 #define DEFINE_MACHINE(namestr, machine_initfn) \

include/hw/cxl/cxl.h

@@ -12,6 +12,7 @@
 
 
 #include "qapi/qapi-types-machine.h"
+#include "qapi/qapi-visit-machine.h"
 #include "hw/pci/pci_bridge.h"
 #include "hw/pci/pci_host.h"
 #include "cxl_pci.h"
@@ -40,6 +41,7 @@ typedef struct CXLState {
     MemoryRegion host_mr;
     unsigned int next_mr_idx;
     GList *fixed_windows;
+    CXLFixedMemoryWindowOptionsList *cfmw_list;
 } CXLState;
 
 struct CXLHost {
@@ -51,11 +53,6 @@ struct CXLHost {
 #define TYPE_PXB_CXL_HOST "pxb-cxl-host"
 OBJECT_DECLARE_SIMPLE_TYPE(CXLHost, PXB_CXL_HOST)
 
-void cxl_fixed_memory_window_config(MachineState *ms,
-                                    CXLFixedMemoryWindowOptions *object,
-                                    Error **errp);
 void cxl_fixed_memory_window_link_targets(Error **errp);
 
-extern const MemoryRegionOps cfmws_ops;
-
 #endif

include/hw/cxl/cxl_host.h

@@ -0,0 +1,21 @@
+/*
+ * QEMU CXL Host Setup
+ *
+ * Copyright (c) 2022 Huawei
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See the
+ * COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/cxl/cxl.h"
+#include "hw/boards.h"
+
+#ifndef CXL_HOST_H
+#define CXL_HOST_H
+
+void cxl_machine_init(Object *obj, CXLState *state);
+
+extern const MemoryRegionOps cfmws_ops;
+
+#endif

qapi/machine.json

@@ -523,6 +523,19 @@
       '*interleave-granularity': 'size',
       'targets': ['str'] }}
 
+##
+# @CXLFMWProperties:
+#
+# List of CXL Fixed Memory Windows.
+#
+# @cxl-fmw: List of CXLFixedMemoryWindowOptions
+#
+# Since 7.1
+##
+{ 'struct' : 'CXLFMWProperties',
+  'data': { 'cxl-fmw': ['CXLFixedMemoryWindowOptions'] }
+}
+
 ##
 # @X86CPURegister32:
 #

qemu-options.hx

@@ -36,7 +36,8 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
     "                nvdimm=on|off controls NVDIMM support (default=off)\n"
     "                memory-encryption=@var{} memory encryption object to use (default=none)\n"
     "                hmat=on|off controls ACPI HMAT support (default=off)\n"
-    "                memory-backend='backend-id' specifies explicitly provided backend for main RAM (default=none)\n",
+    "                memory-backend='backend-id' specifies explicitly provided backend for main RAM (default=none)\n"
+    "                cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]\n",
     QEMU_ARCH_ALL)
 SRST
 ``-machine [type=]name[,prop=value[,...]]``
@@ -124,6 +125,38 @@ SRST
             -object memory-backend-ram,id=pc.ram,size=512M,x-use-canonical-path-for-ramblock-id=off
             -machine memory-backend=pc.ram
             -m 512M
+
+    ``cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]``
+        Define a CXL Fixed Memory Window (CFMW).
+
+        Described in the CXL 2.0 ECN: CEDT CFMWS & QTG _DSM.
+
+        They are regions of Host Physical Addresses (HPA) on a system which
+        may be interleaved across one or more CXL host bridges.  The system
+        software will assign particular devices into these windows and
+        configure the downstream Host-managed Device Memory (HDM) decoders
+        in root ports, switch ports and devices appropriately to meet the
+        interleave requirements before enabling the memory devices.
+
+        ``targets.X=target`` provides the mapping to CXL host bridges
+        which may be identified by the id provied in the -device entry.
+        Multiple entries are needed to specify all the targets when
+        the fixed memory window represents interleaved memory. X is the
+        target index from 0.
+
+        ``size=size`` sets the size of the CFMW. This must be a multiple of
+        256MiB. The region will be aligned to 256MiB but the location is
+        platform and configuration dependent.
+
+        ``interleave-granularity=granularity`` sets the granularity of
+        interleave. Default 256KiB. Only 256KiB, 512KiB, 1024KiB, 2048KiB
+        4096KiB, 8192KiB and 16384KiB granularities supported.
+
+        Example:
+
+        ::
+
+            -machine cxl-fmw.0.targets.0=cxl.0,cxl-fmw.0.targets.1=cxl.1,cxl-fmw.0.size=128G,cxl-fmw.0.interleave-granularity=512k
 ERST
 
 DEF("M", HAS_ARG, QEMU_OPTION_M,
@@ -467,44 +500,6 @@ SRST
         -numa hmat-cache,node-id=1,size=10K,level=1,associativity=direct,policy=write-back,line=8
 ERST
 
-DEF("cxl-fixed-memory-window", HAS_ARG, QEMU_OPTION_cxl_fixed_memory_window,
-    "-cxl-fixed-memory-window targets.0=firsttarget,targets.1=secondtarget,size=size[,interleave-granularity=granularity]\n",
-    QEMU_ARCH_ALL)
-SRST
-``-cxl-fixed-memory-window targets.0=firsttarget,targets.1=secondtarget,size=size[,interleave-granularity=granularity]``
-    Define a CXL Fixed Memory Window (CFMW).
-
-    Described in the CXL 2.0 ECN: CEDT CFMWS & QTG _DSM.
-
-    They are regions of Host Physical Addresses (HPA) on a system which
-    may be interleaved across one or more CXL host bridges.  The system
-    software will assign particular devices into these windows and
-    configure the downstream Host-managed Device Memory (HDM) decoders
-    in root ports, switch ports and devices appropriately to meet the
-    interleave requirements before enabling the memory devices.
-
-    ``targets.X=firsttarget`` provides the mapping to CXL host bridges
-    which may be identified by the id provied in the -device entry.
-    Multiple entries are needed to specify all the targets when
-    the fixed memory window represents interleaved memory. X is the
-    target index from 0.
-
-    ``size=size`` sets the size of the CFMW. This must be a multiple of
-    256MiB. The region will be aligned to 256MiB but the location is
-    platform and configuration dependent.
-
-    ``interleave-granularity=granularity`` sets the granularity of
-    interleave. Default 256KiB. Only 256KiB, 512KiB, 1024KiB, 2048KiB
-    4096KiB, 8192KiB and 16384KiB granularities supported.
-
-    Example:
-
-    ::
-
-        -cxl-fixed-memory-window targets.0=cxl.0,targets.1=cxl.1,size=128G,interleave-granularity=512k
-
-ERST
-
 DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
     "-add-fd fd=fd,set=set[,opaque=opaque]\n"
     "                Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)

softmmu/vl.c

@@ -147,12 +147,6 @@ typedef struct BlockdevOptionsQueueEntry {
 
 typedef QSIMPLEQ_HEAD(, BlockdevOptionsQueueEntry) BlockdevOptionsQueue;
 
-typedef struct CXLFMWOptionQueueEntry {
-    CXLFixedMemoryWindowOptions *opts;
-    Location loc;
-    QSIMPLEQ_ENTRY(CXLFMWOptionQueueEntry) entry;
-} CXLFMWOptionQueueEntry;
-
 typedef struct ObjectOption {
     ObjectOptions *opts;
     QTAILQ_ENTRY(ObjectOption) next;
@@ -179,8 +173,6 @@ static int snapshot;
 static bool preconfig_requested;
 static QemuPluginList plugin_list = QTAILQ_HEAD_INITIALIZER(plugin_list);
 static BlockdevOptionsQueue bdo_queue = QSIMPLEQ_HEAD_INITIALIZER(bdo_queue);
-static QSIMPLEQ_HEAD(, CXLFMWOptionQueueEntry) CXLFMW_opts =
-    QSIMPLEQ_HEAD_INITIALIZER(CXLFMW_opts);
 static bool nographic = false;
 static int mem_prealloc; /* force preallocation of physical target memory */
 static const char *vga_model = NULL;
@@ -1072,24 +1064,6 @@ static void parse_display(const char *p)
     }
 }
 
-static void parse_cxl_fixed_memory_window(const char *optarg)
-{
-    CXLFMWOptionQueueEntry *cfmws_entry;
-    Visitor *v;
-
-    v = qobject_input_visitor_new_str(optarg, "cxl-fixed-memory-window",
-                                      &error_fatal);
-    cfmws_entry = g_new(CXLFMWOptionQueueEntry, 1);
-    visit_type_CXLFixedMemoryWindowOptions(v, NULL, &cfmws_entry->opts,
-                                           &error_fatal);
-    if (!cfmws_entry->opts) {
-        exit(1);
-    }
-    visit_free(v);
-    loc_save(&cfmws_entry->loc);
-    QSIMPLEQ_INSERT_TAIL(&CXLFMW_opts, cfmws_entry, entry);
-}
-
 static inline bool nonempty_str(const char *str)
 {
     return str && *str;
@@ -1948,20 +1922,6 @@ static void qemu_create_late_backends(void)
     qemu_semihosting_console_init();
 }
 
-static void cxl_set_opts(void)
-{
-    while (!QSIMPLEQ_EMPTY(&CXLFMW_opts)) {
-        CXLFMWOptionQueueEntry *cfmws_entry = QSIMPLEQ_FIRST(&CXLFMW_opts);
-
-        loc_restore(&cfmws_entry->loc);
-        QSIMPLEQ_REMOVE_HEAD(&CXLFMW_opts, entry);
-        cxl_fixed_memory_window_config(current_machine, cfmws_entry->opts,
-                                       &error_fatal);
-        qapi_free_CXLFixedMemoryWindowOptions(cfmws_entry->opts);
-        g_free(cfmws_entry);
-    }
-}
-
 static void qemu_resolve_machine_memdev(void)
 {
     if (ram_memdev_id) {
@@ -2789,9 +2749,6 @@ void qemu_init(int argc, char **argv, char **envp)
                     exit(1);
                 }
                 break;
-            case QEMU_OPTION_cxl_fixed_memory_window:
-                parse_cxl_fixed_memory_window(optarg);
-                break;
             case QEMU_OPTION_display:
                 parse_display(optarg);
                 break;
@@ -3598,7 +3555,6 @@ void qemu_init(int argc, char **argv, char **envp)
 
     qemu_resolve_machine_memdev();
     parse_numa_opts(current_machine);
-    cxl_set_opts();
 
     if (vmstate_dump_file) {
         /* dump and exit */

tests/qtest/bios-tables-test.c

@@ -1582,8 +1582,8 @@ static void test_acpi_q35_cxl(void)
                              " -device cxl-type3,bus=rp3,memdev=cxl-mem3,lsa=lsa3"
                              " -device cxl-rp,port=1,bus=cxl.2,id=rp4,chassis=0,slot=6"
                              " -device cxl-type3,bus=rp4,memdev=cxl-mem4,lsa=lsa4"
-                             " -cxl-fixed-memory-window targets.0=cxl.1,size=4G,interleave-granularity=8k"
-                             " -cxl-fixed-memory-window targets.0=cxl.1,targets.1=cxl.2,size=4G,interleave-granularity=8k",
+                             " -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.size=4G,cxl-fmw.0.interleave-granularity=8k,"
+                             "cxl-fmw.1.targets.0=cxl.1,cxl-fmw.1.targets.1=cxl.2,cxl-fmw.1.size=4G,cxl-fmw.1.interleave-granularity=8k",
                              tmp_path, tmp_path, tmp_path, tmp_path,
                              tmp_path, tmp_path, tmp_path, tmp_path);
     test_acpi_one(params, &data);

tests/qtest/cxl-test.c

@@ -10,12 +10,12 @@
 
 #define QEMU_PXB_CMD "-machine q35,cxl=on " \
                      "-device pxb-cxl,id=cxl.0,bus=pcie.0,bus_nr=52 "  \
-                     "-cxl-fixed-memory-window targets.0=cxl.0,size=4G "
+                     "-M cxl-fmw.0.targets.0=cxl.0,cxl-fmw.0.size=4G "
 
 #define QEMU_2PXB_CMD "-machine q35,cxl=on "                            \
                       "-device pxb-cxl,id=cxl.0,bus=pcie.0,bus_nr=52 "  \
                       "-device pxb-cxl,id=cxl.1,bus=pcie.0,bus_nr=53 " \
-                      "-cxl-fixed-memory-window targets.0=cxl.0,targets.1=cxl.1,size=4G "
+                      "-M cxl-fmw.0.targets.0=cxl.0,cxl-fmw.0.targets.1=cxl.1,cxl-fmw.0.size=4G "
 
 #define QEMU_RP "-device cxl-rp,id=rp0,bus=cxl.0,chassis=0,slot=0 "