{"id":2230525,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2230525/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260429135717.3048713-9-joshualant@gmail.com/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.1/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20260429135717.3048713-9-joshualant@gmail.com>","date":"2026-04-29T13:48:42","name":"[RFC,QEMU,08/10] cxl-cci-mailbox: Add support for targeting a VCS switch","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"c86890b0a5507082970f25fd99a153480bffcac7","submitter":{"id":93283,"url":"http://patchwork.ozlabs.org/api/1.1/people/93283/?format=json","name":"Joshua Lant","email":"joshualant@gmail.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260429135717.3048713-9-joshualant@gmail.com/mbox/","series":[{"id":502144,"url":"http://patchwork.ozlabs.org/api/1.1/series/502144/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=502144","date":"2026-04-29T13:48:40","name":"Initial Support for VCS Switching","version":1,"mbox":"http://patchwork.ozlabs.org/series/502144/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2230525/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2230525/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=AY1XTYdY;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; 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helo=mail-wr1-x435.google.com","X-Spam_score_int":"-10","X-Spam_score":"-1.1","X-Spam_bar":"-","X-Spam_report":"(-1.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1,\n DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FORGED_GMAIL_RCVD=1,\n FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001,\n SPF_PASS=-0.001 autolearn=no autolearn_force=no","X-Spam_action":"no action","X-Mailman-Approved-At":"Wed, 29 Apr 2026 16:03:14 -0400","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"qemu development ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"Allows a cci mailbox and mctp device to target a cxl-vcs-switch. The\ntarget needs to be changed from a PCIDevice to a more generic Object,\nsince the target can now also be a cxl-vcs-switch, as well as USP or\ntype3 device. The VCS is an object which is composed of many\nPCI devices, but cannot be classed as one itself (since it is busless).\n\nSigned-off-by: Joshua Lant \n---\n hw/cxl/cxl-mailbox-utils.c | 44 +++++++++++++++++++++++--------------\n hw/cxl/switch-mailbox-cci.c | 33 ++++++++++++++++++++++------\n hw/usb/dev-mctp.c | 23 ++++++++++++++++---\n include/hw/cxl/cxl_device.h | 10 ++++++++-\n 4 files changed, 83 insertions(+), 27 deletions(-)","diff":"diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c\nindex f12e42a648..779138cdc8 100644\n--- a/hw/cxl/cxl-mailbox-utils.c\n+++ b/hw/cxl/cxl-mailbox-utils.c\n@@ -4600,22 +4600,24 @@ int cxl_process_cci_message(CXLCCI *cci, uint8_t set, uint8_t cmd,\n }\n \n /* forbid any selected commands while the media is disabled */\n- if (object_dynamic_cast(OBJECT(cci->d), TYPE_CXL_TYPE3)) {\n- cxl_dstate = &CXL_TYPE3(cci->d)->cxl_dstate;\n-\n- if (cxl_dev_media_disabled(cxl_dstate)) {\n- if (h == cmd_events_get_records ||\n- h == cmd_ccls_get_partition_info ||\n- h == cmd_ccls_set_lsa ||\n- h == cmd_ccls_get_lsa ||\n- h == cmd_logs_get_log ||\n- h == cmd_media_get_poison_list ||\n- h == cmd_media_inject_poison ||\n- h == cmd_media_clear_poison ||\n- h == cmd_sanitize_overwrite ||\n- h == cmd_firmware_update_transfer ||\n- h == cmd_firmware_update_activate) {\n- return CXL_MBOX_MEDIA_DISABLED;\n+ if(cci->d) {\n+ if (object_dynamic_cast(OBJECT(cci->d), TYPE_CXL_TYPE3)) {\n+ cxl_dstate = &CXL_TYPE3(cci->d)->cxl_dstate;\n+\n+ if (cxl_dev_media_disabled(cxl_dstate)) {\n+ if (h == cmd_events_get_records ||\n+ h == cmd_ccls_get_partition_info ||\n+ h == cmd_ccls_set_lsa ||\n+ h == cmd_ccls_get_lsa ||\n+ h == cmd_logs_get_log ||\n+ h == cmd_media_get_poison_list ||\n+ h == cmd_media_inject_poison ||\n+ h == cmd_media_clear_poison ||\n+ h == cmd_sanitize_overwrite ||\n+ h == cmd_firmware_update_transfer ||\n+ h == cmd_firmware_update_activate) {\n+ return CXL_MBOX_MEDIA_DISABLED;\n+ }\n }\n }\n }\n@@ -4909,3 +4911,13 @@ void cxl_initialize_usp_mctpcci(CXLCCI *cci, DeviceState *d, DeviceState *intf,\n cci->intf = intf;\n cxl_init_cci(cci, payload_max);\n }\n+\n+void cxl_initialize_vcs_mctpcci(CXLCCI *cci, CXLVCSSwitch *vcs, DeviceState *d,\n+ DeviceState *intf, size_t payload_max)\n+{\n+ cxl_copy_cci_commands(cci, cxl_cmd_set_usp_mctp);\n+ cci->vcs = vcs;\n+ cci->d = d;\n+ cci->intf = intf;\n+ cxl_init_cci(cci, payload_max);\n+}\ndiff --git a/hw/cxl/switch-mailbox-cci.c b/hw/cxl/switch-mailbox-cci.c\nindex 223f220433..73f76484cc 100644\n--- a/hw/cxl/switch-mailbox-cci.c\n+++ b/hw/cxl/switch-mailbox-cci.c\n@@ -16,6 +16,7 @@\n #include \"qemu/module.h\"\n #include \"hw/qdev-properties.h\"\n #include \"hw/cxl/cxl.h\"\n+#include \"include/hw/cxl/cxl_vcs_switch.h\"\n \n #define CXL_SWCCI_MSIX_MBOX 3\n \n@@ -32,17 +33,26 @@ static void cswbcci_realize(PCIDevice *pci_dev, Error **errp)\n CXLDeviceState *cxl_dstate = &cswmb->cxl_dstate;\n CXLDVSECRegisterLocator *regloc_dvsec;\n CXLUpstreamPort *usp;\n+ CXLVCSSwitch *vcs = 0;\n \n if (!cswmb->target) {\n- error_setg(errp, \"Target not set\");\n+ error_setg(errp, \"No target or vcs has been set...\");\n return;\n }\n- usp = CXL_USP(cswmb->target);\n \n pcie_endpoint_cap_init(pci_dev, 0x80);\n cxl_cstate->dvsec_offset = 0x100;\n cxl_cstate->pdev = pci_dev;\n- cswmb->cci = &usp->swcci;\n+ if (object_dynamic_cast(cswmb->target, TYPE_CXL_VCS_SWITCH)) {\n+\tvcs = CXL_VCS_SWITCH(cswmb->target);\n+\tcswmb->cci = &vcs->swcci;\n+ } else if (object_dynamic_cast(cswmb->target, TYPE_CXL_USP)) {\n+\tusp = CXL_USP(cswmb->target);\n+\tcswmb->cci = &usp->swcci;\n+ } else {\n+\terror_setg(errp, \"Target must be a VCS switch or USP\");\n+\treturn;\n+ }\n cxl_device_register_block_init(OBJECT(pci_dev), cxl_dstate, cswmb->cci);\n pci_register_bar(pci_dev, 0,\n PCI_BASE_ADDRESS_SPACE_MEMORY |\n@@ -57,9 +67,18 @@ static void cswbcci_realize(PCIDevice *pci_dev, Error **errp)\n REG_LOC_DVSEC_LENGTH, REG_LOC_DVSEC,\n REG_LOC_DVSEC_REVID, (uint8_t *)regloc_dvsec);\n \n- cxl_initialize_mailbox_swcci(cswmb->cci, DEVICE(pci_dev),\n- DEVICE(cswmb->target),\n- CXL_MAILBOX_MAX_PAYLOAD_SIZE);\n+ if(vcs) {\n+\tif(vcs->usp_ppbs[0]) {\n+\t cxl_initialize_vcs_mctpcci(cswmb->cci,\n+\t\tvcs, DEVICE(vcs->usp_ppbs[0]->usp), DEVICE(pci_dev), CXL_MAILBOX_MAX_PAYLOAD_SIZE);\n+\t} else {\n+\t error_setg(errp, \"The VCS requires a master USP...\");\n+\t}\n+ } else {\n+\tcxl_initialize_mailbox_swcci(cswmb->cci, DEVICE(pci_dev),\n+\t\t\t\t DEVICE(CXL_USP(cswmb->target)),\n+\t\t\t\t CXL_MAILBOX_MAX_PAYLOAD_SIZE);\n+ }\n }\n \n static void cswmbcci_exit(PCIDevice *pci_dev)\n@@ -69,7 +88,7 @@ static void cswmbcci_exit(PCIDevice *pci_dev)\n \n static const Property cxl_switch_cci_props[] = {\n DEFINE_PROP_LINK(\"target\", CSWMBCCIDev,\n- target, TYPE_CXL_USP, PCIDevice *),\n+ target, TYPE_OBJECT, Object *),\n };\n \n static void cswmbcci_class_init(ObjectClass *oc, const void *data)\ndiff --git a/hw/usb/dev-mctp.c b/hw/usb/dev-mctp.c\nindex aafb9e7e96..792a375245 100644\n--- a/hw/usb/dev-mctp.c\n+++ b/hw/usb/dev-mctp.c\n@@ -25,6 +25,7 @@\n #include \"hw/usb.h\"\n #include \"hw/usb/desc.h\"\n #include \"net/mctp.h\"\n+#include \"include/hw/cxl/cxl_vcs_switch.h\"\n \n /* TODO: Move to header */\n \n@@ -77,7 +78,7 @@ enum cxl_dev_type {\n \n typedef struct USBCXLMCTPState {\n USBDevice dev;\n- PCIDevice *target;\n+ Object *target;\n CXLCCI *cci;\n enum cxl_dev_type type;\n USBPacket *cached_tohost;\n@@ -600,12 +601,28 @@ static void usb_cxl_mctp_realize(USBDevice *dev, Error **errp)\n return;\n }\n \n+ if (object_dynamic_cast(OBJECT(s->target), TYPE_CXL_VCS_SWITCH)) {\n+ CXLVCSSwitch *sw = CXL_VCS_SWITCH(s->target);\n+\n+ s->type = cxl_switch;\n+ s->cci = &sw->mctpcci;\n+\ts->cci->vcs = sw;\n+\n+\tif(sw->usp_ppbs[0]) {\n+\t cxl_initialize_vcs_mctpcci(s->cci, CXL_VCS_SWITCH(s->target),\n+\t\tDEVICE(sw->usp_ppbs[0]->usp), DEVICE(dev), MCTP_CXL_MAILBOX_BYTES);\n+\t} else {\n+\t error_setg(errp, \"No master USP associated with the VCS\");\n+\t}\n+ return;\n+ }\n+\n error_setg(errp, \"Unhandled target type for CXL MCTP EP\");\n }\n \n static const Property usb_cxl_mctp_properties[] = {\n- DEFINE_PROP_LINK(\"target\", USBCXLMCTPState, target, TYPE_PCI_DEVICE,\n- PCIDevice *),\n+ DEFINE_PROP_LINK(\"target\", USBCXLMCTPState, target, TYPE_OBJECT,\n+ Object *),\n };\n \n static void usb_cxl_mctp_class_initfn(ObjectClass *klass, const void *data)\ndiff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h\nindex 6158560e6c..5d9f537a03 100644\n--- a/include/hw/cxl/cxl_device.h\n+++ b/include/hw/cxl/cxl_device.h\n@@ -143,6 +143,7 @@ typedef enum {\n } CXLDSMASFlags;\n \n typedef struct CXLCCI CXLCCI;\n+typedef struct CXLVCSSwitch CXLVCSSwitch;\n typedef struct cxl_device_state CXLDeviceState;\n struct cxl_cmd;\n typedef CXLRetCode (*opcode_handler)(const struct cxl_cmd *cmd,\n@@ -212,6 +213,8 @@ typedef struct CXLCCI {\n DeviceState *d;\n /* Pointer to the device hosting the protocol conversion */\n DeviceState *intf;\n+ /* Pointer to the vcs hosting the CCI (if used) */\n+ CXLVCSSwitch *vcs;\n bool initialized;\n } CXLCCI;\n \n@@ -349,6 +352,10 @@ void cxl_initialize_t3_ld_cci(CXLCCI *cci, DeviceState *d,\n void cxl_initialize_usp_mctpcci(CXLCCI *cci, DeviceState *d, DeviceState *intf,\n size_t payload_max);\n \n+void cxl_initialize_vcs_mctpcci(CXLCCI *cci, CXLVCSSwitch *vcs,\n+\tDeviceState *d, DeviceState *intf, size_t payload_max);\n+\n+\n #define cxl_device_cap_init(dstate, reg, cap_id, ver) \\\n do { \\\n uint32_t *cap_hdrs = dstate->caps_reg_state32; \\\n@@ -820,9 +827,10 @@ struct CXLType3Class {\n uint8_t *data);\n };\n \n+\n struct CSWMBCCIDev {\n PCIDevice parent_obj;\n- PCIDevice *target;\n+ Object *target;\n CXLComponentState cxl_cstate;\n CXLDeviceState cxl_dstate;\n CXLCCI *cci;\n","prefixes":["RFC","QEMU","08/10"]}