Hyper-V vPCI offers different protocol versions. Add the infra for negotiating the one to use.
Signed-off-by: Ajay Kaher akaher@vmware.com --- drivers/pci/host/pci-hyperv.c | 72 +++++++++++++++++++++++++++++++------------ 1 file changed, 53 insertions(+), 19 deletions(-)
diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c index 9e44adf..6eed85b 100644 --- a/drivers/pci/host/pci-hyperv.c +++ b/drivers/pci/host/pci-hyperv.c @@ -65,22 +65,37 @@ * major version. */
-#define PCI_MAKE_VERSION(major, minor) ((u32)(((major) << 16) | (major))) +#define PCI_MAKE_VERSION(major, minor) ((u32)(((major) << 16) | (minor))) #define PCI_MAJOR_VERSION(version) ((u32)(version) >> 16) #define PCI_MINOR_VERSION(version) ((u32)(version) & 0xff)
-enum { - PCI_PROTOCOL_VERSION_1_1 = PCI_MAKE_VERSION(1, 1), - PCI_PROTOCOL_VERSION_CURRENT = PCI_PROTOCOL_VERSION_1_1 +enum pci_protocol_version_t { + PCI_PROTOCOL_VERSION_1_1 = PCI_MAKE_VERSION(1, 1), /* Win10 */ };
#define CPU_AFFINITY_ALL -1ULL + +/* + * Supported protocol versions in the order of probing - highest go + * first. + */ +static enum pci_protocol_version_t pci_protocol_versions[] = { + PCI_PROTOCOL_VERSION_1_1, +}; + +/* + * Protocol version negotiated by hv_pci_protocol_negotiation(). + */ +static enum pci_protocol_version_t pci_protocol_version; + #define PCI_CONFIG_MMIO_LENGTH 0x2000 #define CFG_PAGE_OFFSET 0x1000 #define CFG_PAGE_SIZE (PCI_CONFIG_MMIO_LENGTH - CFG_PAGE_OFFSET)
#define MAX_SUPPORTED_MSI_MESSAGES 0x400
+#define STATUS_REVISION_MISMATCH 0xC0000059 + /* * Message Types */ @@ -1789,6 +1804,7 @@ static int hv_pci_protocol_negotiation(struct hv_device *hdev) struct hv_pci_compl comp_pkt; struct pci_packet *pkt; int ret; + int i;
/* * Initiate the handshake with the host and negotiate @@ -1805,26 +1821,44 @@ static int hv_pci_protocol_negotiation(struct hv_device *hdev) pkt->compl_ctxt = &comp_pkt; version_req = (struct pci_version_request *)&pkt->message; version_req->message_type.type = PCI_QUERY_PROTOCOL_VERSION; - version_req->protocol_version = PCI_PROTOCOL_VERSION_CURRENT;
- ret = vmbus_sendpacket(hdev->channel, version_req, - sizeof(struct pci_version_request), - (unsigned long)pkt, VM_PKT_DATA_INBAND, - VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); - if (ret) - goto exit; + for (i = 0; i < ARRAY_SIZE(pci_protocol_versions); i++) { + version_req->protocol_version = pci_protocol_versions[i]; + ret = vmbus_sendpacket(hdev->channel, version_req, + sizeof(struct pci_version_request), + (unsigned long)pkt, VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + if (ret) { + dev_err(&hdev->device, + "PCI Pass-through VSP failed sending version reqquest: %#x", + ret); + goto exit; + }
- wait_for_completion(&comp_pkt.host_event); + wait_for_completion(&comp_pkt.host_event);
- if (comp_pkt.completion_status < 0) { - dev_err(&hdev->device, - "PCI Pass-through VSP failed version request %x\n", - comp_pkt.completion_status); - ret = -EPROTO; - goto exit; + if (comp_pkt.completion_status >= 0) { + pci_protocol_version = pci_protocol_versions[i]; + dev_info(&hdev->device, + "PCI VMBus probing: Using version %#x\n", + pci_protocol_version); + goto exit; + } + + if (comp_pkt.completion_status != STATUS_REVISION_MISMATCH) { + dev_err(&hdev->device, + "PCI Pass-through VSP failed version request: %#x", + comp_pkt.completion_status); + ret = -EPROTO; + goto exit; + } + + reinit_completion(&comp_pkt.host_event); }
- ret = 0; + dev_err(&hdev->device, + "PCI pass-through VSP failed to find supported version"); + ret = -EPROTO;
exit: kfree(pkt);