// SPDX-License-Identifier: GPL-2.0 /* * Endpoint Function Driver to implement Non-Transparent Bridge functionality * * Copyright (C) 2020 Texas Instruments * Author: Kishon Vijay Abraham I */ /* * The PCI NTB function driver configures the SoC with multiple PCIe Endpoint * (EP) controller instances (see diagram below) in such a way that * transactions from one EP controller are routed to the other EP controller. * Once PCI NTB function driver configures the SoC with multiple EP instances, * HOST1 and HOST2 can communicate with each other using SoC as a bridge. * * +-------------+ +-------------+ * | | | | * | HOST1 | | HOST2 | * | | | | * +------^------+ +------^------+ * | | * | | * +---------|-------------------------------------------------|---------+ * | +------v------+ +------v------+ | * | | | | | | * | | EP | | EP | | * | | CONTROLLER1 | | CONTROLLER2 | | * | | <-----------------------------------> | | * | | | | | | * | | | | | | * | | | SoC With Multiple EP Instances | | | * | | | (Configured using NTB Function) | | | * | +-------------+ +-------------+ | * +---------------------------------------------------------------------+ */ #include #include #include #include #include #include static struct workqueue_struct *kpcintb_workqueue; #define COMMAND_CONFIGURE_DOORBELL 1 #define COMMAND_TEARDOWN_DOORBELL 2 #define COMMAND_CONFIGURE_MW 3 #define COMMAND_TEARDOWN_MW 4 #define COMMAND_LINK_UP 5 #define COMMAND_LINK_DOWN 6 #define COMMAND_STATUS_OK 1 #define COMMAND_STATUS_ERROR 2 #define LINK_STATUS_UP BIT(0) #define SPAD_COUNT 64 #define DB_COUNT 4 #define NTB_MW_OFFSET 2 #define DB_COUNT_MASK GENMASK(15, 0) #define MSIX_ENABLE BIT(16) #define MAX_DB_COUNT 32 #define MAX_MW 4 enum epf_ntb_bar { BAR_CONFIG, BAR_PEER_SPAD, BAR_DB_MW1, BAR_MW2, BAR_MW3, BAR_MW4, }; struct epf_ntb { u32 num_mws; u32 db_count; u32 spad_count; struct pci_epf *epf; u64 mws_size[MAX_MW]; struct config_group group; struct epf_ntb_epc *epc[2]; }; #define to_epf_ntb(epf_group) container_of((epf_group), struct epf_ntb, group) struct epf_ntb_epc { u8 func_no; u8 vfunc_no; bool linkup; bool is_msix; int msix_bar; u32 spad_size; struct pci_epc *epc; struct epf_ntb *epf_ntb; void __iomem *mw_addr[6]; size_t msix_table_offset; struct epf_ntb_ctrl *reg; struct pci_epf_bar *epf_bar; enum pci_barno epf_ntb_bar[6]; struct delayed_work cmd_handler; enum pci_epc_interface_type type; const struct pci_epc_features *epc_features; }; struct epf_ntb_ctrl { u32 command; u32 argument; u16 command_status; u16 link_status; u32 topology; u64 addr; u64 size; u32 num_mws; u32 mw1_offset; u32 spad_offset; u32 spad_count; u32 db_entry_size; u32 db_data[MAX_DB_COUNT]; u32 db_offset[MAX_DB_COUNT]; } __packed; static struct pci_epf_header epf_ntb_header = { .vendorid = PCI_ANY_ID, .deviceid = PCI_ANY_ID, .baseclass_code = PCI_BASE_CLASS_MEMORY, .interrupt_pin = PCI_INTERRUPT_INTA, }; /** * epf_ntb_link_up() - Raise link_up interrupt to both the hosts * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @link_up: true or false indicating Link is UP or Down * * Once NTB function in HOST1 and the NTB function in HOST2 invoke * ntb_link_enable(), this NTB function driver will trigger a link event to * the NTB client in both the hosts. */ static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up) { enum pci_epc_interface_type type; struct epf_ntb_epc *ntb_epc; struct epf_ntb_ctrl *ctrl; unsigned int irq_type; struct pci_epc *epc; u8 func_no, vfunc_no; bool is_msix; int ret; for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) { ntb_epc = ntb->epc[type]; epc = ntb_epc->epc; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; is_msix = ntb_epc->is_msix; ctrl = ntb_epc->reg; if (link_up) ctrl->link_status |= LINK_STATUS_UP; else ctrl->link_status &= ~LINK_STATUS_UP; irq_type = is_msix ? PCI_IRQ_MSIX : PCI_IRQ_MSI; ret = pci_epc_raise_irq(epc, func_no, vfunc_no, irq_type, 1); if (ret) { dev_err(&epc->dev, "%s intf: Failed to raise Link Up IRQ\n", pci_epc_interface_string(type)); return ret; } } return 0; } /** * epf_ntb_configure_mw() - Configure the Outbound Address Space for one host * to access the memory window of other host * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * @mw: Index of the memory window (either 0, 1, 2 or 3) * * +-----------------+ +---->+----------------+-----------+-----------------+ * | BAR0 | | | Doorbell 1 +-----------> MSI|X ADDRESS 1 | * +-----------------+ | +----------------+ +-----------------+ * | BAR1 | | | Doorbell 2 +---------+ | | * +-----------------+----+ +----------------+ | | | * | BAR2 | | Doorbell 3 +-------+ | +-----------------+ * +-----------------+----+ +----------------+ | +-> MSI|X ADDRESS 2 | * | BAR3 | | | Doorbell 4 +-----+ | +-----------------+ * +-----------------+ | |----------------+ | | | | * | BAR4 | | | | | | +-----------------+ * +-----------------+ | | MW1 +---+ | +-->+ MSI|X ADDRESS 3|| * | BAR5 | | | | | | +-----------------+ * +-----------------+ +---->-----------------+ | | | | * EP CONTROLLER 1 | | | | +-----------------+ * | | | +---->+ MSI|X ADDRESS 4 | * +----------------+ | +-----------------+ * (A) EP CONTROLLER 2 | | | * (OB SPACE) | | | * +-------> MW1 | * | | * | | * (B) +-----------------+ * | | * | | * | | * | | * | | * +-----------------+ * PCI Address Space * (Managed by HOST2) * * This function performs stage (B) in the above diagram (see MW1) i.e., map OB * address space of memory window to PCI address space. * * This operation requires 3 parameters * 1) Address in the outbound address space * 2) Address in the PCI Address space * 3) Size of the address region to be mapped * * The address in the outbound address space (for MW1, MW2, MW3 and MW4) is * stored in epf_bar corresponding to BAR_DB_MW1 for MW1 and BAR_MW2, BAR_MW3 * BAR_MW4 for rest of the BARs of epf_ntb_epc that is connected to HOST1. This * is populated in epf_ntb_alloc_peer_mem() in this driver. * * The address and size of the PCI address region that has to be mapped would * be provided by HOST2 in ctrl->addr and ctrl->size of epf_ntb_epc that is * connected to HOST2. * * Please note Memory window1 (MW1) and Doorbell registers together will be * mapped to a single BAR (BAR2) above for 32-bit BARs. The exact BAR that's * used for Memory window (MW) can be obtained from epf_ntb_bar[BAR_DB_MW1], * epf_ntb_bar[BAR_MW2], epf_ntb_bar[BAR_MW2], epf_ntb_bar[BAR_MW2]. */ static int epf_ntb_configure_mw(struct epf_ntb *ntb, enum pci_epc_interface_type type, u32 mw) { struct epf_ntb_epc *peer_ntb_epc, *ntb_epc; struct pci_epf_bar *peer_epf_bar; enum pci_barno peer_barno; struct epf_ntb_ctrl *ctrl; phys_addr_t phys_addr; u8 func_no, vfunc_no; struct pci_epc *epc; u64 addr, size; int ret = 0; ntb_epc = ntb->epc[type]; epc = ntb_epc->epc; peer_ntb_epc = ntb->epc[!type]; peer_barno = peer_ntb_epc->epf_ntb_bar[mw + NTB_MW_OFFSET]; peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno]; phys_addr = peer_epf_bar->phys_addr; ctrl = ntb_epc->reg; addr = ctrl->addr; size = ctrl->size; if (mw + NTB_MW_OFFSET == BAR_DB_MW1) phys_addr += ctrl->mw1_offset; if (size > ntb->mws_size[mw]) { dev_err(&epc->dev, "%s intf: MW: %d Req Sz:%llxx > Supported Sz:%llx\n", pci_epc_interface_string(type), mw, size, ntb->mws_size[mw]); ret = -EINVAL; goto err_invalid_size; } func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; ret = pci_epc_map_addr(epc, func_no, vfunc_no, phys_addr, addr, size); if (ret) dev_err(&epc->dev, "%s intf: Failed to map memory window %d address\n", pci_epc_interface_string(type), mw); err_invalid_size: return ret; } /** * epf_ntb_teardown_mw() - Teardown the configured OB ATU * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * @mw: Index of the memory window (either 0, 1, 2 or 3) * * Teardown the configured OB ATU configured in epf_ntb_configure_mw() using * pci_epc_unmap_addr() */ static void epf_ntb_teardown_mw(struct epf_ntb *ntb, enum pci_epc_interface_type type, u32 mw) { struct epf_ntb_epc *peer_ntb_epc, *ntb_epc; struct pci_epf_bar *peer_epf_bar; enum pci_barno peer_barno; struct epf_ntb_ctrl *ctrl; phys_addr_t phys_addr; u8 func_no, vfunc_no; struct pci_epc *epc; ntb_epc = ntb->epc[type]; epc = ntb_epc->epc; peer_ntb_epc = ntb->epc[!type]; peer_barno = peer_ntb_epc->epf_ntb_bar[mw + NTB_MW_OFFSET]; peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno]; phys_addr = peer_epf_bar->phys_addr; ctrl = ntb_epc->reg; if (mw + NTB_MW_OFFSET == BAR_DB_MW1) phys_addr += ctrl->mw1_offset; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; pci_epc_unmap_addr(epc, func_no, vfunc_no, phys_addr); } /** * epf_ntb_configure_msi() - Map OB address space to MSI address * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * @db_count: Number of doorbell interrupts to map * *+-----------------+ +----->+----------------+-----------+-----------------+ *| BAR0 | | | Doorbell 1 +---+-------> MSI ADDRESS | *+-----------------+ | +----------------+ | +-----------------+ *| BAR1 | | | Doorbell 2 +---+ | | *+-----------------+----+ +----------------+ | | | *| BAR2 | | Doorbell 3 +---+ | | *+-----------------+----+ +----------------+ | | | *| BAR3 | | | Doorbell 4 +---+ | | *+-----------------+ | |----------------+ | | *| BAR4 | | | | | | *+-----------------+ | | MW1 | | | *| BAR5 | | | | | | *+-----------------+ +----->-----------------+ | | * EP CONTROLLER 1 | | | | * | | | | * +----------------+ +-----------------+ * (A) EP CONTROLLER 2 | | * (OB SPACE) | | * | MW1 | * | | * | | * (B) +-----------------+ * | | * | | * | | * | | * | | * +-----------------+ * PCI Address Space * (Managed by HOST2) * * * This function performs stage (B) in the above diagram (see Doorbell 1, * Doorbell 2, Doorbell 3, Doorbell 4) i.e map OB address space corresponding to * doorbell to MSI address in PCI address space. * * This operation requires 3 parameters * 1) Address reserved for doorbell in the outbound address space * 2) MSI-X address in the PCIe Address space * 3) Number of MSI-X interrupts that has to be configured * * The address in the outbound address space (for the Doorbell) is stored in * epf_bar corresponding to BAR_DB_MW1 of epf_ntb_epc that is connected to * HOST1. This is populated in epf_ntb_alloc_peer_mem() in this driver along * with address for MW1. * * pci_epc_map_msi_irq() takes the MSI address from MSI capability register * and maps the OB address (obtained in epf_ntb_alloc_peer_mem()) to the MSI * address. * * epf_ntb_configure_msi() also stores the MSI data to raise each interrupt * in db_data of the peer's control region. This helps the peer to raise * doorbell of the other host by writing db_data to the BAR corresponding to * BAR_DB_MW1. */ static int epf_ntb_configure_msi(struct epf_ntb *ntb, enum pci_epc_interface_type type, u16 db_count) { struct epf_ntb_epc *peer_ntb_epc, *ntb_epc; u32 db_entry_size, db_data, db_offset; struct pci_epf_bar *peer_epf_bar; struct epf_ntb_ctrl *peer_ctrl; enum pci_barno peer_barno; phys_addr_t phys_addr; u8 func_no, vfunc_no; struct pci_epc *epc; int ret, i; ntb_epc = ntb->epc[type]; epc = ntb_epc->epc; peer_ntb_epc = ntb->epc[!type]; peer_barno = peer_ntb_epc->epf_ntb_bar[BAR_DB_MW1]; peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno]; peer_ctrl = peer_ntb_epc->reg; db_entry_size = peer_ctrl->db_entry_size; phys_addr = peer_epf_bar->phys_addr; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; ret = pci_epc_map_msi_irq(epc, func_no, vfunc_no, phys_addr, db_count, db_entry_size, &db_data, &db_offset); if (ret) { dev_err(&epc->dev, "%s intf: Failed to map MSI IRQ\n", pci_epc_interface_string(type)); return ret; } for (i = 0; i < db_count; i++) { peer_ctrl->db_data[i] = db_data | i; peer_ctrl->db_offset[i] = db_offset; } return 0; } /** * epf_ntb_configure_msix() - Map OB address space to MSI-X address * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * @db_count: Number of doorbell interrupts to map * *+-----------------+ +----->+----------------+-----------+-----------------+ *| BAR0 | | | Doorbell 1 +-----------> MSI-X ADDRESS 1 | *+-----------------+ | +----------------+ +-----------------+ *| BAR1 | | | Doorbell 2 +---------+ | | *+-----------------+----+ +----------------+ | | | *| BAR2 | | Doorbell 3 +-------+ | +-----------------+ *+-----------------+----+ +----------------+ | +-> MSI-X ADDRESS 2 | *| BAR3 | | | Doorbell 4 +-----+ | +-----------------+ *+-----------------+ | |----------------+ | | | | *| BAR4 | | | | | | +-----------------+ *+-----------------+ | | MW1 + | +-->+ MSI-X ADDRESS 3|| *| BAR5 | | | | | +-----------------+ *+-----------------+ +----->-----------------+ | | | * EP CONTROLLER 1 | | | +-----------------+ * | | +---->+ MSI-X ADDRESS 4 | * +----------------+ +-----------------+ * (A) EP CONTROLLER 2 | | * (OB SPACE) | | * | MW1 | * | | * | | * (B) +-----------------+ * | | * | | * | | * | | * | | * +-----------------+ * PCI Address Space * (Managed by HOST2) * * This function performs stage (B) in the above diagram (see Doorbell 1, * Doorbell 2, Doorbell 3, Doorbell 4) i.e map OB address space corresponding to * doorbell to MSI-X address in PCI address space. * * This operation requires 3 parameters * 1) Address reserved for doorbell in the outbound address space * 2) MSI-X address in the PCIe Address space * 3) Number of MSI-X interrupts that has to be configured * * The address in the outbound address space (for the Doorbell) is stored in * epf_bar corresponding to BAR_DB_MW1 of epf_ntb_epc that is connected to * HOST1. This is populated in epf_ntb_alloc_peer_mem() in this driver along * with address for MW1. * * The MSI-X address is in the MSI-X table of EP CONTROLLER 2 and * the count of doorbell is in ctrl->argument of epf_ntb_epc that is connected * to HOST2. MSI-X table is stored memory mapped to ntb_epc->msix_bar and the * offset is in ntb_epc->msix_table_offset. From this epf_ntb_configure_msix() * gets the MSI-X address and data. * * epf_ntb_configure_msix() also stores the MSI-X data to raise each interrupt * in db_data of the peer's control region. This helps the peer to raise * doorbell of the other host by writing db_data to the BAR corresponding to * BAR_DB_MW1. */ static int epf_ntb_configure_msix(struct epf_ntb *ntb, enum pci_epc_interface_type type, u16 db_count) { const struct pci_epc_features *epc_features; struct epf_ntb_epc *peer_ntb_epc, *ntb_epc; struct pci_epf_bar *peer_epf_bar, *epf_bar; struct pci_epf_msix_tbl *msix_tbl; struct epf_ntb_ctrl *peer_ctrl; u32 db_entry_size, msg_data; enum pci_barno peer_barno; phys_addr_t phys_addr; u8 func_no, vfunc_no; struct pci_epc *epc; size_t align; u64 msg_addr; int ret, i; ntb_epc = ntb->epc[type]; epc = ntb_epc->epc; epf_bar = &ntb_epc->epf_bar[ntb_epc->msix_bar]; msix_tbl = epf_bar->addr + ntb_epc->msix_table_offset; peer_ntb_epc = ntb->epc[!type]; peer_barno = peer_ntb_epc->epf_ntb_bar[BAR_DB_MW1]; peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno]; phys_addr = peer_epf_bar->phys_addr; peer_ctrl = peer_ntb_epc->reg; epc_features = ntb_epc->epc_features; align = epc_features->align; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; db_entry_size = peer_ctrl->db_entry_size; for (i = 0; i < db_count; i++) { msg_addr = ALIGN_DOWN(msix_tbl[i].msg_addr, align); msg_data = msix_tbl[i].msg_data; ret = pci_epc_map_addr(epc, func_no, vfunc_no, phys_addr, msg_addr, db_entry_size); if (ret) { dev_err(&epc->dev, "%s intf: Failed to configure MSI-X IRQ\n", pci_epc_interface_string(type)); return ret; } phys_addr = phys_addr + db_entry_size; peer_ctrl->db_data[i] = msg_data; peer_ctrl->db_offset[i] = msix_tbl[i].msg_addr & (align - 1); } ntb_epc->is_msix = true; return 0; } /** * epf_ntb_configure_db() - Configure the Outbound Address Space for one host * to ring the doorbell of other host * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * @db_count: Count of the number of doorbells that has to be configured * @msix: Indicates whether MSI-X or MSI should be used * * Invokes epf_ntb_configure_msix() or epf_ntb_configure_msi() required for * one HOST to ring the doorbell of other HOST. */ static int epf_ntb_configure_db(struct epf_ntb *ntb, enum pci_epc_interface_type type, u16 db_count, bool msix) { struct epf_ntb_epc *ntb_epc; struct pci_epc *epc; int ret; if (db_count > MAX_DB_COUNT) return -EINVAL; ntb_epc = ntb->epc[type]; epc = ntb_epc->epc; if (msix) ret = epf_ntb_configure_msix(ntb, type, db_count); else ret = epf_ntb_configure_msi(ntb, type, db_count); if (ret) dev_err(&epc->dev, "%s intf: Failed to configure DB\n", pci_epc_interface_string(type)); return ret; } /** * epf_ntb_teardown_db() - Unmap address in OB address space to MSI/MSI-X * address * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * * Invoke pci_epc_unmap_addr() to unmap OB address to MSI/MSI-X address. */ static void epf_ntb_teardown_db(struct epf_ntb *ntb, enum pci_epc_interface_type type) { struct epf_ntb_epc *peer_ntb_epc, *ntb_epc; struct pci_epf_bar *peer_epf_bar; enum pci_barno peer_barno; phys_addr_t phys_addr; u8 func_no, vfunc_no; struct pci_epc *epc; ntb_epc = ntb->epc[type]; epc = ntb_epc->epc; peer_ntb_epc = ntb->epc[!type]; peer_barno = peer_ntb_epc->epf_ntb_bar[BAR_DB_MW1]; peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno]; phys_addr = peer_epf_bar->phys_addr; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; pci_epc_unmap_addr(epc, func_no, vfunc_no, phys_addr); } /** * epf_ntb_cmd_handler() - Handle commands provided by the NTB Host * @work: work_struct for the two epf_ntb_epc (PRIMARY and SECONDARY) * * Workqueue function that gets invoked for the two epf_ntb_epc * periodically (once every 5ms) to see if it has received any commands * from NTB host. The host can send commands to configure doorbell or * configure memory window or to update link status. */ static void epf_ntb_cmd_handler(struct work_struct *work) { enum pci_epc_interface_type type; struct epf_ntb_epc *ntb_epc; struct epf_ntb_ctrl *ctrl; u32 command, argument; struct epf_ntb *ntb; struct device *dev; u16 db_count; bool is_msix; int ret; ntb_epc = container_of(work, struct epf_ntb_epc, cmd_handler.work); ctrl = ntb_epc->reg; command = ctrl->command; if (!command) goto reset_handler; argument = ctrl->argument; ctrl->command = 0; ctrl->argument = 0; ctrl = ntb_epc->reg; type = ntb_epc->type; ntb = ntb_epc->epf_ntb; dev = &ntb->epf->dev; switch (command) { case COMMAND_CONFIGURE_DOORBELL: db_count = argument & DB_COUNT_MASK; is_msix = argument & MSIX_ENABLE; ret = epf_ntb_configure_db(ntb, type, db_count, is_msix); if (ret < 0) ctrl->command_status = COMMAND_STATUS_ERROR; else ctrl->command_status = COMMAND_STATUS_OK; break; case COMMAND_TEARDOWN_DOORBELL: epf_ntb_teardown_db(ntb, type); ctrl->command_status = COMMAND_STATUS_OK; break; case COMMAND_CONFIGURE_MW: ret = epf_ntb_configure_mw(ntb, type, argument); if (ret < 0) ctrl->command_status = COMMAND_STATUS_ERROR; else ctrl->command_status = COMMAND_STATUS_OK; break; case COMMAND_TEARDOWN_MW: epf_ntb_teardown_mw(ntb, type, argument); ctrl->command_status = COMMAND_STATUS_OK; break; case COMMAND_LINK_UP: ntb_epc->linkup = true; if (ntb->epc[PRIMARY_INTERFACE]->linkup && ntb->epc[SECONDARY_INTERFACE]->linkup) { ret = epf_ntb_link_up(ntb, true); if (ret < 0) ctrl->command_status = COMMAND_STATUS_ERROR; else ctrl->command_status = COMMAND_STATUS_OK; goto reset_handler; } ctrl->command_status = COMMAND_STATUS_OK; break; case COMMAND_LINK_DOWN: ntb_epc->linkup = false; ret = epf_ntb_link_up(ntb, false); if (ret < 0) ctrl->command_status = COMMAND_STATUS_ERROR; else ctrl->command_status = COMMAND_STATUS_OK; break; default: dev_err(dev, "%s intf UNKNOWN command: %d\n", pci_epc_interface_string(type), command); break; } reset_handler: queue_delayed_work(kpcintb_workqueue, &ntb_epc->cmd_handler, msecs_to_jiffies(5)); } /** * epf_ntb_peer_spad_bar_clear() - Clear Peer Scratchpad BAR * @ntb_epc: EPC associated with one of the HOST which holds peer's outbound * address. * *+-----------------+------->+------------------+ +-----------------+ *| BAR0 | | CONFIG REGION | | BAR0 | *+-----------------+----+ +------------------+<-------+-----------------+ *| BAR1 | | |SCRATCHPAD REGION | | BAR1 | *+-----------------+ +-->+------------------+<-------+-----------------+ *| BAR2 | Local Memory | BAR2 | *+-----------------+ +-----------------+ *| BAR3 | | BAR3 | *+-----------------+ +-----------------+ *| BAR4 | | BAR4 | *+-----------------+ +-----------------+ *| BAR5 | | BAR5 | *+-----------------+ +-----------------+ * EP CONTROLLER 1 EP CONTROLLER 2 * * Clear BAR1 of EP CONTROLLER 2 which contains the HOST2's peer scratchpad * region. While BAR1 is the default peer scratchpad BAR, an NTB could have * other BARs for peer scratchpad (because of 64-bit BARs or reserved BARs). * This function can get the exact BAR used for peer scratchpad from * epf_ntb_bar[BAR_PEER_SPAD]. * * Since HOST2's peer scratchpad is also HOST1's self scratchpad, this function * gets the address of peer scratchpad from * peer_ntb_epc->epf_ntb_bar[BAR_CONFIG]. */ static void epf_ntb_peer_spad_bar_clear(struct epf_ntb_epc *ntb_epc) { struct pci_epf_bar *epf_bar; enum pci_barno barno; u8 func_no, vfunc_no; struct pci_epc *epc; epc = ntb_epc->epc; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; barno = ntb_epc->epf_ntb_bar[BAR_PEER_SPAD]; epf_bar = &ntb_epc->epf_bar[barno]; pci_epc_clear_bar(epc, func_no, vfunc_no, epf_bar); } /** * epf_ntb_peer_spad_bar_set() - Set peer scratchpad BAR * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * *+-----------------+------->+------------------+ +-----------------+ *| BAR0 | | CONFIG REGION | | BAR0 | *+-----------------+----+ +------------------+<-------+-----------------+ *| BAR1 | | |SCRATCHPAD REGION | | BAR1 | *+-----------------+ +-->+------------------+<-------+-----------------+ *| BAR2 | Local Memory | BAR2 | *+-----------------+ +-----------------+ *| BAR3 | | BAR3 | *+-----------------+ +-----------------+ *| BAR4 | | BAR4 | *+-----------------+ +-----------------+ *| BAR5 | | BAR5 | *+-----------------+ +-----------------+ * EP CONTROLLER 1 EP CONTROLLER 2 * * Set BAR1 of EP CONTROLLER 2 which contains the HOST2's peer scratchpad * region. While BAR1 is the default peer scratchpad BAR, an NTB could have * other BARs for peer scratchpad (because of 64-bit BARs or reserved BARs). * This function can get the exact BAR used for peer scratchpad from * epf_ntb_bar[BAR_PEER_SPAD]. * * Since HOST2's peer scratchpad is also HOST1's self scratchpad, this function * gets the address of peer scratchpad from * peer_ntb_epc->epf_ntb_bar[BAR_CONFIG]. */ static int epf_ntb_peer_spad_bar_set(struct epf_ntb *ntb, enum pci_epc_interface_type type) { struct epf_ntb_epc *peer_ntb_epc, *ntb_epc; struct pci_epf_bar *peer_epf_bar, *epf_bar; enum pci_barno peer_barno, barno; u32 peer_spad_offset; u8 func_no, vfunc_no; struct pci_epc *epc; struct device *dev; int ret; dev = &ntb->epf->dev; peer_ntb_epc = ntb->epc[!type]; peer_barno = peer_ntb_epc->epf_ntb_bar[BAR_CONFIG]; peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno]; ntb_epc = ntb->epc[type]; barno = ntb_epc->epf_ntb_bar[BAR_PEER_SPAD]; epf_bar = &ntb_epc->epf_bar[barno]; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; epc = ntb_epc->epc; peer_spad_offset = peer_ntb_epc->reg->spad_offset; epf_bar->phys_addr = peer_epf_bar->phys_addr + peer_spad_offset; epf_bar->size = peer_ntb_epc->spad_size; epf_bar->barno = barno; epf_bar->flags = PCI_BASE_ADDRESS_MEM_TYPE_32; ret = pci_epc_set_bar(epc, func_no, vfunc_no, epf_bar); if (ret) { dev_err(dev, "%s intf: peer SPAD BAR set failed\n", pci_epc_interface_string(type)); return ret; } return 0; } /** * epf_ntb_config_sspad_bar_clear() - Clear Config + Self scratchpad BAR * @ntb_epc: EPC associated with one of the HOST which holds peer's outbound * address. * * +-----------------+------->+------------------+ +-----------------+ * | BAR0 | | CONFIG REGION | | BAR0 | * +-----------------+----+ +------------------+<-------+-----------------+ * | BAR1 | | |SCRATCHPAD REGION | | BAR1 | * +-----------------+ +-->+------------------+<-------+-----------------+ * | BAR2 | Local Memory | BAR2 | * +-----------------+ +-----------------+ * | BAR3 | | BAR3 | * +-----------------+ +-----------------+ * | BAR4 | | BAR4 | * +-----------------+ +-----------------+ * | BAR5 | | BAR5 | * +-----------------+ +-----------------+ * EP CONTROLLER 1 EP CONTROLLER 2 * * Clear BAR0 of EP CONTROLLER 1 which contains the HOST1's config and * self scratchpad region (removes inbound ATU configuration). While BAR0 is * the default self scratchpad BAR, an NTB could have other BARs for self * scratchpad (because of reserved BARs). This function can get the exact BAR * used for self scratchpad from epf_ntb_bar[BAR_CONFIG]. * * Please note the self scratchpad region and config region is combined to * a single region and mapped using the same BAR. Also note HOST2's peer * scratchpad is HOST1's self scratchpad. */ static void epf_ntb_config_sspad_bar_clear(struct epf_ntb_epc *ntb_epc) { struct pci_epf_bar *epf_bar; enum pci_barno barno; u8 func_no, vfunc_no; struct pci_epc *epc; epc = ntb_epc->epc; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; barno = ntb_epc->epf_ntb_bar[BAR_CONFIG]; epf_bar = &ntb_epc->epf_bar[barno]; pci_epc_clear_bar(epc, func_no, vfunc_no, epf_bar); } /** * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR * @ntb_epc: EPC associated with one of the HOST which holds peer's outbound * address. * * +-----------------+------->+------------------+ +-----------------+ * | BAR0 | | CONFIG REGION | | BAR0 | * +-----------------+----+ +------------------+<-------+-----------------+ * | BAR1 | | |SCRATCHPAD REGION | | BAR1 | * +-----------------+ +-->+------------------+<-------+-----------------+ * | BAR2 | Local Memory | BAR2 | * +-----------------+ +-----------------+ * | BAR3 | | BAR3 | * +-----------------+ +-----------------+ * | BAR4 | | BAR4 | * +-----------------+ +-----------------+ * | BAR5 | | BAR5 | * +-----------------+ +-----------------+ * EP CONTROLLER 1 EP CONTROLLER 2 * * Map BAR0 of EP CONTROLLER 1 which contains the HOST1's config and * self scratchpad region. While BAR0 is the default self scratchpad BAR, an * NTB could have other BARs for self scratchpad (because of reserved BARs). * This function can get the exact BAR used for self scratchpad from * epf_ntb_bar[BAR_CONFIG]. * * Please note the self scratchpad region and config region is combined to * a single region and mapped using the same BAR. Also note HOST2's peer * scratchpad is HOST1's self scratchpad. */ static int epf_ntb_config_sspad_bar_set(struct epf_ntb_epc *ntb_epc) { struct pci_epf_bar *epf_bar; enum pci_barno barno; u8 func_no, vfunc_no; struct epf_ntb *ntb; struct pci_epc *epc; struct device *dev; int ret; ntb = ntb_epc->epf_ntb; dev = &ntb->epf->dev; epc = ntb_epc->epc; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; barno = ntb_epc->epf_ntb_bar[BAR_CONFIG]; epf_bar = &ntb_epc->epf_bar[barno]; ret = pci_epc_set_bar(epc, func_no, vfunc_no, epf_bar); if (ret) { dev_err(dev, "%s inft: Config/Status/SPAD BAR set failed\n", pci_epc_interface_string(ntb_epc->type)); return ret; } return 0; } /** * epf_ntb_config_spad_bar_free() - Free the physical memory associated with * config + scratchpad region * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * * +-----------------+------->+------------------+ +-----------------+ * | BAR0 | | CONFIG REGION | | BAR0 | * +-----------------+----+ +------------------+<-------+-----------------+ * | BAR1 | | |SCRATCHPAD REGION | | BAR1 | * +-----------------+ +-->+------------------+<-------+-----------------+ * | BAR2 | Local Memory | BAR2 | * +-----------------+ +-----------------+ * | BAR3 | | BAR3 | * +-----------------+ +-----------------+ * | BAR4 | | BAR4 | * +-----------------+ +-----------------+ * | BAR5 | | BAR5 | * +-----------------+ +-----------------+ * EP CONTROLLER 1 EP CONTROLLER 2 * * Free the Local Memory mentioned in the above diagram. After invoking this * function, any of config + self scratchpad region of HOST1 or peer scratchpad * region of HOST2 should not be accessed. */ static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb) { enum pci_epc_interface_type type; struct epf_ntb_epc *ntb_epc; enum pci_barno barno; struct pci_epf *epf; epf = ntb->epf; for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) { ntb_epc = ntb->epc[type]; barno = ntb_epc->epf_ntb_bar[BAR_CONFIG]; if (ntb_epc->reg) pci_epf_free_space(epf, ntb_epc->reg, barno, type); } } /** * epf_ntb_config_spad_bar_alloc() - Allocate memory for config + scratchpad * region * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * * +-----------------+------->+------------------+ +-----------------+ * | BAR0 | | CONFIG REGION | | BAR0 | * +-----------------+----+ +------------------+<-------+-----------------+ * | BAR1 | | |SCRATCHPAD REGION | | BAR1 | * +-----------------+ +-->+------------------+<-------+-----------------+ * | BAR2 | Local Memory | BAR2 | * +-----------------+ +-----------------+ * | BAR3 | | BAR3 | * +-----------------+ +-----------------+ * | BAR4 | | BAR4 | * +-----------------+ +-----------------+ * | BAR5 | | BAR5 | * +-----------------+ +-----------------+ * EP CONTROLLER 1 EP CONTROLLER 2 * * Allocate the Local Memory mentioned in the above diagram. The size of * CONFIG REGION is sizeof(struct epf_ntb_ctrl) and size of SCRATCHPAD REGION * is obtained from "spad-count" configfs entry. * * The size of both config region and scratchpad region has to be aligned, * since the scratchpad region will also be mapped as PEER SCRATCHPAD of * other host using a separate BAR. */ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb, enum pci_epc_interface_type type) { const struct pci_epc_features *peer_epc_features, *epc_features; struct epf_ntb_epc *peer_ntb_epc, *ntb_epc; size_t msix_table_size, pba_size, align; enum pci_barno peer_barno, barno; struct epf_ntb_ctrl *ctrl; u32 spad_size, ctrl_size; u64 size, peer_size; struct pci_epf *epf; struct device *dev; bool msix_capable; u32 spad_count; void *base; epf = ntb->epf; dev = &epf->dev; ntb_epc = ntb->epc[type]; epc_features = ntb_epc->epc_features; barno = ntb_epc->epf_ntb_bar[BAR_CONFIG]; size = epc_features->bar[barno].fixed_size; align = epc_features->align; peer_ntb_epc = ntb->epc[!type]; peer_epc_features = peer_ntb_epc->epc_features; peer_barno = ntb_epc->epf_ntb_bar[BAR_PEER_SPAD]; peer_size = peer_epc_features->bar[peer_barno].fixed_size; /* Check if epc_features is populated incorrectly */ if ((!IS_ALIGNED(size, align))) return -EINVAL; spad_count = ntb->spad_count; ctrl_size = sizeof(struct epf_ntb_ctrl); spad_size = spad_count * 4; msix_capable = epc_features->msix_capable; if (msix_capable) { msix_table_size = PCI_MSIX_ENTRY_SIZE * ntb->db_count; ctrl_size = ALIGN(ctrl_size, 8); ntb_epc->msix_table_offset = ctrl_size; ntb_epc->msix_bar = barno; /* Align to QWORD or 8 Bytes */ pba_size = ALIGN(DIV_ROUND_UP(ntb->db_count, 8), 8); ctrl_size = ctrl_size + msix_table_size + pba_size; } if (!align) { ctrl_size = roundup_pow_of_two(ctrl_size); spad_size = roundup_pow_of_two(spad_size); } else { ctrl_size = ALIGN(ctrl_size, align); spad_size = ALIGN(spad_size, align); } if (peer_size) { if (peer_size < spad_size) spad_count = peer_size / 4; spad_size = peer_size; } /* * In order to make sure SPAD offset is aligned to its size, * expand control region size to the size of SPAD if SPAD size * is greater than control region size. */ if (spad_size > ctrl_size) ctrl_size = spad_size; if (!size) size = ctrl_size + spad_size; else if (size < ctrl_size + spad_size) return -EINVAL; base = pci_epf_alloc_space(epf, size, barno, epc_features, type); if (!base) { dev_err(dev, "%s intf: Config/Status/SPAD alloc region fail\n", pci_epc_interface_string(type)); return -ENOMEM; } ntb_epc->reg = base; ctrl = ntb_epc->reg; ctrl->spad_offset = ctrl_size; ctrl->spad_count = spad_count; ctrl->num_mws = ntb->num_mws; ctrl->db_entry_size = align ? align : 4; ntb_epc->spad_size = spad_size; return 0; } /** * epf_ntb_config_spad_bar_alloc_interface() - Allocate memory for config + * scratchpad region for each of PRIMARY and SECONDARY interface * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * * Wrapper for epf_ntb_config_spad_bar_alloc() which allocates memory for * config + scratchpad region for a specific interface */ static int epf_ntb_config_spad_bar_alloc_interface(struct epf_ntb *ntb) { enum pci_epc_interface_type type; struct device *dev; int ret; dev = &ntb->epf->dev; for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) { ret = epf_ntb_config_spad_bar_alloc(ntb, type); if (ret) { dev_err(dev, "%s intf: Config/SPAD BAR alloc failed\n", pci_epc_interface_string(type)); return ret; } } return 0; } /** * epf_ntb_free_peer_mem() - Free memory allocated in peers outbound address * space * @ntb_epc: EPC associated with one of the HOST which holds peers outbound * address regions * * +-----------------+ +---->+----------------+-----------+-----------------+ * | BAR0 | | | Doorbell 1 +-----------> MSI|X ADDRESS 1 | * +-----------------+ | +----------------+ +-----------------+ * | BAR1 | | | Doorbell 2 +---------+ | | * +-----------------+----+ +----------------+ | | | * | BAR2 | | Doorbell 3 +-------+ | +-----------------+ * +-----------------+----+ +----------------+ | +-> MSI|X ADDRESS 2 | * | BAR3 | | | Doorbell 4 +-----+ | +-----------------+ * +-----------------+ | |----------------+ | | | | * | BAR4 | | | | | | +-----------------+ * +-----------------+ | | MW1 +---+ | +-->+ MSI|X ADDRESS 3|| * | BAR5 | | | | | | +-----------------+ * +-----------------+ +---->-----------------+ | | | | * EP CONTROLLER 1 | | | | +-----------------+ * | | | +---->+ MSI|X ADDRESS 4 | * +----------------+ | +-----------------+ * (A) EP CONTROLLER 2 | | | * (OB SPACE) | | | * +-------> MW1 | * | | * | | * (B) +-----------------+ * | | * | | * | | * | | * | | * +-----------------+ * PCI Address Space * (Managed by HOST2) * * Free memory allocated in EP CONTROLLER 2 (OB SPACE) in the above diagram. * It'll free Doorbell 1, Doorbell 2, Doorbell 3, Doorbell 4, MW1 (and MW2, MW3, * MW4). */ static void epf_ntb_free_peer_mem(struct epf_ntb_epc *ntb_epc) { struct pci_epf_bar *epf_bar; void __iomem *mw_addr; phys_addr_t phys_addr; enum epf_ntb_bar bar; enum pci_barno barno; struct pci_epc *epc; size_t size; epc = ntb_epc->epc; for (bar = BAR_DB_MW1; bar < BAR_MW4; bar++) { barno = ntb_epc->epf_ntb_bar[bar]; mw_addr = ntb_epc->mw_addr[barno]; epf_bar = &ntb_epc->epf_bar[barno]; phys_addr = epf_bar->phys_addr; size = epf_bar->size; if (mw_addr) { pci_epc_mem_free_addr(epc, phys_addr, mw_addr, size); ntb_epc->mw_addr[barno] = NULL; } } } /** * epf_ntb_db_mw_bar_clear() - Clear doorbell and memory BAR * @ntb_epc: EPC associated with one of the HOST which holds peer's outbound * address * * +-----------------+ +---->+----------------+-----------+-----------------+ * | BAR0 | | | Doorbell 1 +-----------> MSI|X ADDRESS 1 | * +-----------------+ | +----------------+ +-----------------+ * | BAR1 | | | Doorbell 2 +---------+ | | * +-----------------+----+ +----------------+ | | | * | BAR2 | | Doorbell 3 +-------+ | +-----------------+ * +-----------------+----+ +----------------+ | +-> MSI|X ADDRESS 2 | * | BAR3 | | | Doorbell 4 +-----+ | +-----------------+ * +-----------------+ | |----------------+ | | | | * | BAR4 | | | | | | +-----------------+ * +-----------------+ | | MW1 +---+ | +-->+ MSI|X ADDRESS 3|| * | BAR5 | | | | | | +-----------------+ * +-----------------+ +---->-----------------+ | | | | * EP CONTROLLER 1 | | | | +-----------------+ * | | | +---->+ MSI|X ADDRESS 4 | * +----------------+ | +-----------------+ * (A) EP CONTROLLER 2 | | | * (OB SPACE) | | | * +-------> MW1 | * | | * | | * (B) +-----------------+ * | | * | | * | | * | | * | | * +-----------------+ * PCI Address Space * (Managed by HOST2) * * Clear doorbell and memory BARs (remove inbound ATU configuration). In the above * diagram it clears BAR2 TO BAR5 of EP CONTROLLER 1 (Doorbell BAR, MW1 BAR, MW2 * BAR, MW3 BAR and MW4 BAR). */ static void epf_ntb_db_mw_bar_clear(struct epf_ntb_epc *ntb_epc) { struct pci_epf_bar *epf_bar; enum epf_ntb_bar bar; enum pci_barno barno; u8 func_no, vfunc_no; struct pci_epc *epc; epc = ntb_epc->epc; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; for (bar = BAR_DB_MW1; bar < BAR_MW4; bar++) { barno = ntb_epc->epf_ntb_bar[bar]; epf_bar = &ntb_epc->epf_bar[barno]; pci_epc_clear_bar(epc, func_no, vfunc_no, epf_bar); } } /** * epf_ntb_db_mw_bar_cleanup() - Clear doorbell/memory BAR and free memory * allocated in peers outbound address space * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * * Wrapper for epf_ntb_db_mw_bar_clear() to clear HOST1's BAR and * epf_ntb_free_peer_mem() which frees up HOST2 outbound memory. */ static void epf_ntb_db_mw_bar_cleanup(struct epf_ntb *ntb, enum pci_epc_interface_type type) { struct epf_ntb_epc *peer_ntb_epc, *ntb_epc; ntb_epc = ntb->epc[type]; peer_ntb_epc = ntb->epc[!type]; epf_ntb_db_mw_bar_clear(ntb_epc); epf_ntb_free_peer_mem(peer_ntb_epc); } /** * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capability * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * * Configure MSI/MSI-X capability for each interface with number of * interrupts equal to "db_count" configfs entry. */ static int epf_ntb_configure_interrupt(struct epf_ntb *ntb, enum pci_epc_interface_type type) { const struct pci_epc_features *epc_features; bool msix_capable, msi_capable; struct epf_ntb_epc *ntb_epc; u8 func_no, vfunc_no; struct pci_epc *epc; struct device *dev; u32 db_count; int ret; ntb_epc = ntb->epc[type]; dev = &ntb->epf->dev; epc_features = ntb_epc->epc_features; msix_capable = epc_features->msix_capable; msi_capable = epc_features->msi_capable; if (!(msix_capable || msi_capable)) { dev_err(dev, "MSI or MSI-X is required for doorbell\n"); return -EINVAL; } func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; db_count = ntb->db_count; if (db_count > MAX_DB_COUNT) { dev_err(dev, "DB count cannot be more than %d\n", MAX_DB_COUNT); return -EINVAL; } ntb->db_count = db_count; epc = ntb_epc->epc; if (msi_capable) { ret = pci_epc_set_msi(epc, func_no, vfunc_no, db_count); if (ret) { dev_err(dev, "%s intf: MSI configuration failed\n", pci_epc_interface_string(type)); return ret; } } if (msix_capable) { ret = pci_epc_set_msix(epc, func_no, vfunc_no, db_count, ntb_epc->msix_bar, ntb_epc->msix_table_offset); if (ret) { dev_err(dev, "MSI configuration failed\n"); return ret; } } return 0; } /** * epf_ntb_alloc_peer_mem() - Allocate memory in peer's outbound address space * @dev: The PCI device. * @ntb_epc: EPC associated with one of the HOST whose BAR holds peer's outbound * address * @bar: BAR of @ntb_epc in for which memory has to be allocated (could be * BAR_DB_MW1, BAR_MW2, BAR_MW3, BAR_MW4) * @peer_ntb_epc: EPC associated with HOST whose outbound address space is * used by @ntb_epc * @size: Size of the address region that has to be allocated in peers OB SPACE * * * +-----------------+ +---->+----------------+-----------+-----------------+ * | BAR0 | | | Doorbell 1 +-----------> MSI|X ADDRESS 1 | * +-----------------+ | +----------------+ +-----------------+ * | BAR1 | | | Doorbell 2 +---------+ | | * +-----------------+----+ +----------------+ | | | * | BAR2 | | Doorbell 3 +-------+ | +-----------------+ * +-----------------+----+ +----------------+ | +-> MSI|X ADDRESS 2 | * | BAR3 | | | Doorbell 4 +-----+ | +-----------------+ * +-----------------+ | |----------------+ | | | | * | BAR4 | | | | | | +-----------------+ * +-----------------+ | | MW1 +---+ | +-->+ MSI|X ADDRESS 3|| * | BAR5 | | | | | | +-----------------+ * +-----------------+ +---->-----------------+ | | | | * EP CONTROLLER 1 | | | | +-----------------+ * | | | +---->+ MSI|X ADDRESS 4 | * +----------------+ | +-----------------+ * (A) EP CONTROLLER 2 | | | * (OB SPACE) | | | * +-------> MW1 | * | | * | | * (B) +-----------------+ * | | * | | * | | * | | * | | * +-----------------+ * PCI Address Space * (Managed by HOST2) * * Allocate memory in OB space of EP CONTROLLER 2 in the above diagram. Allocate * for Doorbell 1, Doorbell 2, Doorbell 3, Doorbell 4, MW1 (and MW2, MW3, MW4). */ static int epf_ntb_alloc_peer_mem(struct device *dev, struct epf_ntb_epc *ntb_epc, enum epf_ntb_bar bar, struct epf_ntb_epc *peer_ntb_epc, size_t size) { const struct pci_epc_features *epc_features; struct pci_epf_bar *epf_bar; struct pci_epc *peer_epc; phys_addr_t phys_addr; void __iomem *mw_addr; enum pci_barno barno; size_t align; epc_features = ntb_epc->epc_features; align = epc_features->align; if (size < 128) size = 128; if (align) size = ALIGN(size, align); else size = roundup_pow_of_two(size); peer_epc = peer_ntb_epc->epc; mw_addr = pci_epc_mem_alloc_addr(peer_epc, &phys_addr, size); if (!mw_addr) { dev_err(dev, "%s intf: Failed to allocate OB address\n", pci_epc_interface_string(peer_ntb_epc->type)); return -ENOMEM; } barno = ntb_epc->epf_ntb_bar[bar]; epf_bar = &ntb_epc->epf_bar[barno]; ntb_epc->mw_addr[barno] = mw_addr; epf_bar->phys_addr = phys_addr; epf_bar->size = size; epf_bar->barno = barno; epf_bar->flags = PCI_BASE_ADDRESS_MEM_TYPE_32; return 0; } /** * epf_ntb_db_mw_bar_init() - Configure Doorbell and Memory window BARs * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * * Wrapper for epf_ntb_alloc_peer_mem() and pci_epc_set_bar() that allocates * memory in OB address space of HOST2 and configures BAR of HOST1 */ static int epf_ntb_db_mw_bar_init(struct epf_ntb *ntb, enum pci_epc_interface_type type) { const struct pci_epc_features *epc_features; struct epf_ntb_epc *peer_ntb_epc, *ntb_epc; struct pci_epf_bar *epf_bar; struct epf_ntb_ctrl *ctrl; u32 num_mws, db_count; enum epf_ntb_bar bar; enum pci_barno barno; u8 func_no, vfunc_no; struct pci_epc *epc; struct device *dev; size_t align; int ret, i; u64 size; ntb_epc = ntb->epc[type]; peer_ntb_epc = ntb->epc[!type]; dev = &ntb->epf->dev; epc_features = ntb_epc->epc_features; align = epc_features->align; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; epc = ntb_epc->epc; num_mws = ntb->num_mws; db_count = ntb->db_count; for (bar = BAR_DB_MW1, i = 0; i < num_mws; bar++, i++) { if (bar == BAR_DB_MW1) { align = align ? align : 4; size = db_count * align; size = ALIGN(size, ntb->mws_size[i]); ctrl = ntb_epc->reg; ctrl->mw1_offset = size; size += ntb->mws_size[i]; } else { size = ntb->mws_size[i]; } ret = epf_ntb_alloc_peer_mem(dev, ntb_epc, bar, peer_ntb_epc, size); if (ret) { dev_err(dev, "%s intf: DoorBell mem alloc failed\n", pci_epc_interface_string(type)); goto err_alloc_peer_mem; } barno = ntb_epc->epf_ntb_bar[bar]; epf_bar = &ntb_epc->epf_bar[barno]; ret = pci_epc_set_bar(epc, func_no, vfunc_no, epf_bar); if (ret) { dev_err(dev, "%s intf: DoorBell BAR set failed\n", pci_epc_interface_string(type)); goto err_alloc_peer_mem; } } return 0; err_alloc_peer_mem: epf_ntb_db_mw_bar_cleanup(ntb, type); return ret; } /** * epf_ntb_epc_destroy_interface() - Cleanup NTB EPC interface * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * * Unbind NTB function device from EPC and relinquish reference to pci_epc * for each of the interface. */ static void epf_ntb_epc_destroy_interface(struct epf_ntb *ntb, enum pci_epc_interface_type type) { struct epf_ntb_epc *ntb_epc; struct pci_epc *epc; struct pci_epf *epf; if (type < 0) return; epf = ntb->epf; ntb_epc = ntb->epc[type]; if (!ntb_epc) return; epc = ntb_epc->epc; pci_epc_remove_epf(epc, epf, type); pci_epc_put(epc); } /** * epf_ntb_epc_destroy() - Cleanup NTB EPC interface * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB interfaces */ static void epf_ntb_epc_destroy(struct epf_ntb *ntb) { enum pci_epc_interface_type type; for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) epf_ntb_epc_destroy_interface(ntb, type); } /** * epf_ntb_epc_create_interface() - Create and initialize NTB EPC interface * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @epc: struct pci_epc to which a particular NTB interface should be associated * @type: PRIMARY interface or SECONDARY interface * * Allocate memory for NTB EPC interface and initialize it. */ static int epf_ntb_epc_create_interface(struct epf_ntb *ntb, struct pci_epc *epc, enum pci_epc_interface_type type) { const struct pci_epc_features *epc_features; struct pci_epf_bar *epf_bar; struct epf_ntb_epc *ntb_epc; u8 func_no, vfunc_no; struct pci_epf *epf; struct device *dev; dev = &ntb->epf->dev; ntb_epc = devm_kzalloc(dev, sizeof(*ntb_epc), GFP_KERNEL); if (!ntb_epc) return -ENOMEM; epf = ntb->epf; vfunc_no = epf->vfunc_no; if (type == PRIMARY_INTERFACE) { func_no = epf->func_no; epf_bar = epf->bar; } else { func_no = epf->sec_epc_func_no; epf_bar = epf->sec_epc_bar; } ntb_epc->linkup = false; ntb_epc->epc = epc; ntb_epc->func_no = func_no; ntb_epc->vfunc_no = vfunc_no; ntb_epc->type = type; ntb_epc->epf_bar = epf_bar; ntb_epc->epf_ntb = ntb; epc_features = pci_epc_get_features(epc, func_no, vfunc_no); if (!epc_features) return -EINVAL; ntb_epc->epc_features = epc_features; ntb->epc[type] = ntb_epc; return 0; } /** * epf_ntb_epc_create() - Create and initialize NTB EPC interface * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * * Get a reference to EPC device and bind NTB function device to that EPC * for each of the interface. It is also a wrapper to * epf_ntb_epc_create_interface() to allocate memory for NTB EPC interface * and initialize it */ static int epf_ntb_epc_create(struct epf_ntb *ntb) { struct pci_epf *epf; struct device *dev; int ret; epf = ntb->epf; dev = &epf->dev; ret = epf_ntb_epc_create_interface(ntb, epf->epc, PRIMARY_INTERFACE); if (ret) { dev_err(dev, "PRIMARY intf: Fail to create NTB EPC\n"); return ret; } ret = epf_ntb_epc_create_interface(ntb, epf->sec_epc, SECONDARY_INTERFACE); if (ret) { dev_err(dev, "SECONDARY intf: Fail to create NTB EPC\n"); goto err_epc_create; } return 0; err_epc_create: epf_ntb_epc_destroy_interface(ntb, PRIMARY_INTERFACE); return ret; } /** * epf_ntb_init_epc_bar_interface() - Identify BARs to be used for each of * the NTB constructs (scratchpad region, doorbell, memorywindow) * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * * Identify the free BARs to be used for each of BAR_CONFIG, BAR_PEER_SPAD, * BAR_DB_MW1, BAR_MW2, BAR_MW3 and BAR_MW4. */ static int epf_ntb_init_epc_bar_interface(struct epf_ntb *ntb, enum pci_epc_interface_type type) { const struct pci_epc_features *epc_features; struct epf_ntb_epc *ntb_epc; enum pci_barno barno; enum epf_ntb_bar bar; struct device *dev; u32 num_mws; int i; barno = BAR_0; ntb_epc = ntb->epc[type]; num_mws = ntb->num_mws; dev = &ntb->epf->dev; epc_features = ntb_epc->epc_features; /* These are required BARs which are mandatory for NTB functionality */ for (bar = BAR_CONFIG; bar <= BAR_DB_MW1; bar++, barno++) { barno = pci_epc_get_next_free_bar(epc_features, barno); if (barno < 0) { dev_err(dev, "%s intf: Fail to get NTB function BAR\n", pci_epc_interface_string(type)); return barno; } ntb_epc->epf_ntb_bar[bar] = barno; } /* These are optional BARs which don't impact NTB functionality */ for (bar = BAR_MW2, i = 1; i < num_mws; bar++, barno++, i++) { barno = pci_epc_get_next_free_bar(epc_features, barno); if (barno < 0) { ntb->num_mws = i; dev_dbg(dev, "BAR not available for > MW%d\n", i + 1); } ntb_epc->epf_ntb_bar[bar] = barno; } return 0; } /** * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB * constructs (scratchpad region, doorbell, memorywindow) * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * * Wrapper to epf_ntb_init_epc_bar_interface() to identify the free BARs * to be used for each of BAR_CONFIG, BAR_PEER_SPAD, BAR_DB_MW1, BAR_MW2, * BAR_MW3 and BAR_MW4 for all the interfaces. */ static int epf_ntb_init_epc_bar(struct epf_ntb *ntb) { enum pci_epc_interface_type type; struct device *dev; int ret; dev = &ntb->epf->dev; for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) { ret = epf_ntb_init_epc_bar_interface(ntb, type); if (ret) { dev_err(dev, "Fail to init EPC bar for %s interface\n", pci_epc_interface_string(type)); return ret; } } return 0; } /** * epf_ntb_epc_init_interface() - Initialize NTB interface * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * * Wrapper to initialize a particular EPC interface and start the workqueue * to check for commands from host. This function will write to the * EP controller HW for configuring it. */ static int epf_ntb_epc_init_interface(struct epf_ntb *ntb, enum pci_epc_interface_type type) { struct epf_ntb_epc *ntb_epc; u8 func_no, vfunc_no; struct pci_epc *epc; struct pci_epf *epf; struct device *dev; int ret; ntb_epc = ntb->epc[type]; epf = ntb->epf; dev = &epf->dev; epc = ntb_epc->epc; func_no = ntb_epc->func_no; vfunc_no = ntb_epc->vfunc_no; ret = epf_ntb_config_sspad_bar_set(ntb->epc[type]); if (ret) { dev_err(dev, "%s intf: Config/self SPAD BAR init failed\n", pci_epc_interface_string(type)); return ret; } ret = epf_ntb_peer_spad_bar_set(ntb, type); if (ret) { dev_err(dev, "%s intf: Peer SPAD BAR init failed\n", pci_epc_interface_string(type)); goto err_peer_spad_bar_init; } ret = epf_ntb_configure_interrupt(ntb, type); if (ret) { dev_err(dev, "%s intf: Interrupt configuration failed\n", pci_epc_interface_string(type)); goto err_peer_spad_bar_init; } ret = epf_ntb_db_mw_bar_init(ntb, type); if (ret) { dev_err(dev, "%s intf: DB/MW BAR init failed\n", pci_epc_interface_string(type)); goto err_db_mw_bar_init; } if (vfunc_no <= 1) { ret = pci_epc_write_header(epc, func_no, vfunc_no, epf->header); if (ret) { dev_err(dev, "%s intf: Configuration header write failed\n", pci_epc_interface_string(type)); goto err_write_header; } } INIT_DELAYED_WORK(&ntb->epc[type]->cmd_handler, epf_ntb_cmd_handler); queue_work(kpcintb_workqueue, &ntb->epc[type]->cmd_handler.work); return 0; err_write_header: epf_ntb_db_mw_bar_cleanup(ntb, type); err_db_mw_bar_init: epf_ntb_peer_spad_bar_clear(ntb->epc[type]); err_peer_spad_bar_init: epf_ntb_config_sspad_bar_clear(ntb->epc[type]); return ret; } /** * epf_ntb_epc_cleanup_interface() - Cleanup NTB interface * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * @type: PRIMARY interface or SECONDARY interface * * Wrapper to cleanup a particular NTB interface. */ static void epf_ntb_epc_cleanup_interface(struct epf_ntb *ntb, enum pci_epc_interface_type type) { struct epf_ntb_epc *ntb_epc; if (type < 0) return; ntb_epc = ntb->epc[type]; cancel_delayed_work(&ntb_epc->cmd_handler); epf_ntb_db_mw_bar_cleanup(ntb, type); epf_ntb_peer_spad_bar_clear(ntb_epc); epf_ntb_config_sspad_bar_clear(ntb_epc); } /** * epf_ntb_epc_cleanup() - Cleanup all NTB interfaces * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * * Wrapper to cleanup all NTB interfaces. */ static void epf_ntb_epc_cleanup(struct epf_ntb *ntb) { enum pci_epc_interface_type type; for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) epf_ntb_epc_cleanup_interface(ntb, type); } /** * epf_ntb_epc_init() - Initialize all NTB interfaces * @ntb: NTB device that facilitates communication between HOST1 and HOST2 * * Wrapper to initialize all NTB interface and start the workqueue * to check for commands from host. */ static int epf_ntb_epc_init(struct epf_ntb *ntb) { enum pci_epc_interface_type type; struct device *dev; int ret; dev = &ntb->epf->dev; for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) { ret = epf_ntb_epc_init_interface(ntb, type); if (ret) { dev_err(dev, "%s intf: Failed to initialize\n", pci_epc_interface_string(type)); goto err_init_type; } } return 0; err_init_type: epf_ntb_epc_cleanup_interface(ntb, type - 1); return ret; } /** * epf_ntb_bind() - Initialize endpoint controller to provide NTB functionality * @epf: NTB endpoint function device * * Initialize both the endpoint controllers associated with NTB function device. * Invoked when a primary interface or secondary interface is bound to EPC * device. This function will succeed only when EPC is bound to both the * interfaces. */ static int epf_ntb_bind(struct pci_epf *epf) { struct epf_ntb *ntb = epf_get_drvdata(epf); struct device *dev = &epf->dev; int ret; if (!epf->epc) { dev_dbg(dev, "PRIMARY EPC interface not yet bound\n"); return 0; } if (!epf->sec_epc) { dev_dbg(dev, "SECONDARY EPC interface not yet bound\n"); return 0; } ret = epf_ntb_epc_create(ntb); if (ret) { dev_err(dev, "Failed to create NTB EPC\n"); return ret; } ret = epf_ntb_init_epc_bar(ntb); if (ret) { dev_err(dev, "Failed to create NTB EPC\n"); goto err_bar_init; } ret = epf_ntb_config_spad_bar_alloc_interface(ntb); if (ret) { dev_err(dev, "Failed to allocate BAR memory\n"); goto err_bar_alloc; } ret = epf_ntb_epc_init(ntb); if (ret) { dev_err(dev, "Failed to initialize EPC\n"); goto err_bar_alloc; } epf_set_drvdata(epf, ntb); return 0; err_bar_alloc: epf_ntb_config_spad_bar_free(ntb); err_bar_init: epf_ntb_epc_destroy(ntb); return ret; } /** * epf_ntb_unbind() - Cleanup the initialization from epf_ntb_bind() * @epf: NTB endpoint function device * * Cleanup the initialization from epf_ntb_bind() */ static void epf_ntb_unbind(struct pci_epf *epf) { struct epf_ntb *ntb = epf_get_drvdata(epf); epf_ntb_epc_cleanup(ntb); epf_ntb_config_spad_bar_free(ntb); epf_ntb_epc_destroy(ntb); } #define EPF_NTB_R(_name) \ static ssize_t epf_ntb_##_name##_show(struct config_item *item, \ char *page) \ { \ struct config_group *group = to_config_group(item); \ struct epf_ntb *ntb = to_epf_ntb(group); \ \ return sysfs_emit(page, "%d\n", ntb->_name); \ } #define EPF_NTB_W(_name) \ static ssize_t epf_ntb_##_name##_store(struct config_item *item, \ const char *page, size_t len) \ { \ struct config_group *group = to_config_group(item); \ struct epf_ntb *ntb = to_epf_ntb(group); \ u32 val; \ \ if (kstrtou32(page, 0, &val) < 0) \ return -EINVAL; \ \ ntb->_name = val; \ \ return len; \ } #define EPF_NTB_MW_R(_name) \ static ssize_t epf_ntb_##_name##_show(struct config_item *item, \ char *page) \ { \ struct config_group *group = to_config_group(item); \ struct epf_ntb *ntb = to_epf_ntb(group); \ int win_no; \ \ sscanf(#_name, "mw%d", &win_no); \ \ return sysfs_emit(page, "%lld\n", ntb->mws_size[win_no - 1]); \ } #define EPF_NTB_MW_W(_name) \ static ssize_t epf_ntb_##_name##_store(struct config_item *item, \ const char *page, size_t len) \ { \ struct config_group *group = to_config_group(item); \ struct epf_ntb *ntb = to_epf_ntb(group); \ struct device *dev = &ntb->epf->dev; \ int win_no; \ u64 val; \ \ if (kstrtou64(page, 0, &val) < 0) \ return -EINVAL; \ \ if (sscanf(#_name, "mw%d", &win_no) != 1) \ return -EINVAL; \ \ if (ntb->num_mws < win_no) { \ dev_err(dev, "Invalid num_nws: %d value\n", ntb->num_mws); \ return -EINVAL; \ } \ \ ntb->mws_size[win_no - 1] = val; \ \ return len; \ } static ssize_t epf_ntb_num_mws_store(struct config_item *item, const char *page, size_t len) { struct config_group *group = to_config_group(item); struct epf_ntb *ntb = to_epf_ntb(group); u32 val; if (kstrtou32(page, 0, &val) < 0) return -EINVAL; if (val > MAX_MW) return -EINVAL; ntb->num_mws = val; return len; } EPF_NTB_R(spad_count) EPF_NTB_W(spad_count) EPF_NTB_R(db_count) EPF_NTB_W(db_count) EPF_NTB_R(num_mws) EPF_NTB_MW_R(mw1) EPF_NTB_MW_W(mw1) EPF_NTB_MW_R(mw2) EPF_NTB_MW_W(mw2) EPF_NTB_MW_R(mw3) EPF_NTB_MW_W(mw3) EPF_NTB_MW_R(mw4) EPF_NTB_MW_W(mw4) CONFIGFS_ATTR(epf_ntb_, spad_count); CONFIGFS_ATTR(epf_ntb_, db_count); CONFIGFS_ATTR(epf_ntb_, num_mws); CONFIGFS_ATTR(epf_ntb_, mw1); CONFIGFS_ATTR(epf_ntb_, mw2); CONFIGFS_ATTR(epf_ntb_, mw3); CONFIGFS_ATTR(epf_ntb_, mw4); static struct configfs_attribute *epf_ntb_attrs[] = { &epf_ntb_attr_spad_count, &epf_ntb_attr_db_count, &epf_ntb_attr_num_mws, &epf_ntb_attr_mw1, &epf_ntb_attr_mw2, &epf_ntb_attr_mw3, &epf_ntb_attr_mw4, NULL, }; static const struct config_item_type ntb_group_type = { .ct_attrs = epf_ntb_attrs, .ct_owner = THIS_MODULE, }; /** * epf_ntb_add_cfs() - Add configfs directory specific to NTB * @epf: NTB endpoint function device * @group: A pointer to the config_group structure referencing a group of * config_items of a specific type that belong to a specific sub-system. * * Add configfs directory specific to NTB. This directory will hold * NTB specific properties like db_count, spad_count, num_mws etc., */ static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf, struct config_group *group) { struct epf_ntb *ntb = epf_get_drvdata(epf); struct config_group *ntb_group = &ntb->group; struct device *dev = &epf->dev; config_group_init_type_name(ntb_group, dev_name(dev), &ntb_group_type); return ntb_group; } /** * epf_ntb_probe() - Probe NTB function driver * @epf: NTB endpoint function device * @id: NTB endpoint function device ID * * Probe NTB function driver when endpoint function bus detects a NTB * endpoint function. */ static int epf_ntb_probe(struct pci_epf *epf, const struct pci_epf_device_id *id) { struct epf_ntb *ntb; struct device *dev; dev = &epf->dev; ntb = devm_kzalloc(dev, sizeof(*ntb), GFP_KERNEL); if (!ntb) return -ENOMEM; epf->header = &epf_ntb_header; ntb->epf = epf; epf_set_drvdata(epf, ntb); return 0; } static const struct pci_epf_ops epf_ntb_ops = { .bind = epf_ntb_bind, .unbind = epf_ntb_unbind, .add_cfs = epf_ntb_add_cfs, }; static const struct pci_epf_device_id epf_ntb_ids[] = { { .name = "pci_epf_ntb", }, {}, }; static struct pci_epf_driver epf_ntb_driver = { .driver.name = "pci_epf_ntb", .probe = epf_ntb_probe, .id_table = epf_ntb_ids, .ops = &epf_ntb_ops, .owner = THIS_MODULE, }; static int __init epf_ntb_init(void) { int ret; kpcintb_workqueue = alloc_workqueue("kpcintb", WQ_MEM_RECLAIM | WQ_HIGHPRI, 0); ret = pci_epf_register_driver(&epf_ntb_driver); if (ret) { destroy_workqueue(kpcintb_workqueue); pr_err("Failed to register pci epf ntb driver --> %d\n", ret); return ret; } return 0; } module_init(epf_ntb_init); static void __exit epf_ntb_exit(void) { pci_epf_unregister_driver(&epf_ntb_driver); destroy_workqueue(kpcintb_workqueue); } module_exit(epf_ntb_exit); MODULE_DESCRIPTION("PCI EPF NTB DRIVER"); MODULE_AUTHOR("Kishon Vijay Abraham I "); MODULE_LICENSE("GPL v2");