To establish performance characteristics of a CXL device when used via a particular CXL topology (root ports, switches, end points) it is necessary to set the appropriate link speed and width in the PCI Express capability structure. Provide x-speed and x-link properties for this.
Signed-off-by: Jonathan Cameron <jonathan.came...@huawei.com> --- include/hw/cxl/cxl_device.h | 4 ++++ hw/mem/cxl_type3.c | 6 ++++++ 2 files changed, 10 insertions(+) diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h index fdd0f4e62b..e14e56ae4b 100644 --- a/include/hw/cxl/cxl_device.h +++ b/include/hw/cxl/cxl_device.h @@ -549,6 +549,10 @@ struct CXLType3Dev { CXLCCI vdm_fm_owned_ld_mctp_cci; CXLCCI ld0_cci; + /* PCIe link characteristics */ + PCIExpLinkSpeed speed; + PCIExpLinkWidth width; + /* DOE */ DOECap doe_cdat; diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c index 235ac40aeb..44d491d8f6 100644 --- a/hw/mem/cxl_type3.c +++ b/hw/mem/cxl_type3.c @@ -17,6 +17,7 @@ #include "hw/mem/pc-dimm.h" #include "hw/pci/pci.h" #include "hw/qdev-properties.h" +#include "hw/qdev-properties-system.h" #include "qapi/error.h" #include "qemu/log.h" #include "qemu/module.h" @@ -1200,6 +1201,7 @@ static void ct3d_reset(DeviceState *dev) uint32_t *reg_state = ct3d->cxl_cstate.crb.cache_mem_registers; uint32_t *write_msk = ct3d->cxl_cstate.crb.cache_mem_regs_write_mask; + pcie_cap_fill_link_ep_usp(PCI_DEVICE(dev), ct3d->width, ct3d->speed); cxl_component_register_init_common(reg_state, write_msk, CXL2_TYPE3_DEVICE); cxl_device_register_init_t3(ct3d); @@ -1229,6 +1231,10 @@ static Property ct3_props[] = { DEFINE_PROP_UINT8("num-dc-regions", CXLType3Dev, dc.num_regions, 0), DEFINE_PROP_LINK("volatile-dc-memdev", CXLType3Dev, dc.host_dc, TYPE_MEMORY_BACKEND, HostMemoryBackend *), + DEFINE_PROP_PCIE_LINK_SPEED("x-speed", CXLType3Dev, + speed, PCIE_LINK_SPEED_32), + DEFINE_PROP_PCIE_LINK_WIDTH("x-width", CXLType3Dev, + width, PCIE_LINK_WIDTH_16), DEFINE_PROP_END_OF_LIST(), }; -- 2.43.0