From: Frank Li <Frank.Li@xxxxxxx> [ Upstream commit e35f56bb03304abc92c928b641af41ca372966bb ] Add NTB function driver and virtual PCI Bus and Virtual NTB driver to implement communication between PCIe Root Port and PCIe EP devices ┌────────────┐ ┌─────────────────────────────────────┐ │ │ │ │ ├────────────┤ │ ┌──────────────┤ │ NTB │ │ │ NTB │ │ NetDev │ │ │ NetDev │ ├────────────┤ │ ├──────────────┤ │ NTB │ │ │ NTB │ │ Transfer │ │ │ Transfer │ ├────────────┤ │ ├──────────────┤ │ │ │ │ │ │ PCI NTB │ │ │ │ │ EPF │ │ │ │ │ Driver │ │ │ PCI Virtual │ │ │ ├───────────────┐ │ NTB Driver │ │ │ │ PCI EP NTB │◄────►│ │ │ │ │ FN Driver │ │ │ ├────────────┤ ├───────────────┤ ├──────────────┤ │ │ │ │ │ │ │ PCI Bus │ ◄─────► │ PCI EP Bus │ │ Virtual PCI │ │ │ PCI │ │ │ Bus │ └────────────┘ └───────────────┴──────┴──────────────┘ PCIe Root Port PCI EP This driver includes 3 parts: 1 PCI EP NTB function driver 2 Virtual PCI bus 3 PCI virtual NTB driver, which is loaded only by above virtual PCI bus Signed-off-by: Frank Li <Frank.Li@xxxxxxx> Signed-off-by: Jon Mason <jdmason@xxxxxxxx> Stable-dep-of: aebfdfe39b93 ("NTB: fix possible name leak in ntb_register_device()") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/pci/endpoint/functions/Kconfig | 11 + drivers/pci/endpoint/functions/Makefile | 1 + drivers/pci/endpoint/functions/pci-epf-vntb.c | 1424 +++++++++++++++++ 3 files changed, 1436 insertions(+) create mode 100644 drivers/pci/endpoint/functions/pci-epf-vntb.c diff --git a/drivers/pci/endpoint/functions/Kconfig b/drivers/pci/endpoint/functions/Kconfig index 5f1242ca2f4e4..65217428d17b9 100644 --- a/drivers/pci/endpoint/functions/Kconfig +++ b/drivers/pci/endpoint/functions/Kconfig @@ -25,3 +25,14 @@ config PCI_EPF_NTB device tree. If in doubt, say "N" to disable Endpoint NTB driver. + +config PCI_EPF_VNTB + tristate "PCI Endpoint NTB driver" + depends on PCI_ENDPOINT + select CONFIGFS_FS + help + Select this configuration option to enable the Non-Transparent + Bridge (NTB) driver for PCIe Endpoint. NTB driver implements NTB + between PCI Root Port and PCIe Endpoint. + + If in doubt, say "N" to disable Endpoint NTB driver. diff --git a/drivers/pci/endpoint/functions/Makefile b/drivers/pci/endpoint/functions/Makefile index 96ab932a537a2..5c13001deaba1 100644 --- a/drivers/pci/endpoint/functions/Makefile +++ b/drivers/pci/endpoint/functions/Makefile @@ -5,3 +5,4 @@ obj-$(CONFIG_PCI_EPF_TEST) += pci-epf-test.o obj-$(CONFIG_PCI_EPF_NTB) += pci-epf-ntb.o +obj-$(CONFIG_PCI_EPF_VNTB) += pci-epf-vntb.o diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c new file mode 100644 index 0000000000000..1466dd1904175 --- /dev/null +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c @@ -0,0 +1,1424 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Endpoint Function Driver to implement Non-Transparent Bridge functionality + * Between PCI RC and EP + * + * Copyright (C) 2020 Texas Instruments + * Copyright (C) 2022 NXP + * + * Based on pci-epf-ntb.c + * Author: Frank Li <Frank.Li@xxxxxxx> + * Author: Kishon Vijay Abraham I <kishon@xxxxxx> + */ + +/** + * +------------+ +---------------------------------------+ + * | | | | + * +------------+ | +--------------+ + * | NTB | | | NTB | + * | NetDev | | | NetDev | + * +------------+ | +--------------+ + * | NTB | | | NTB | + * | Transfer | | | Transfer | + * +------------+ | +--------------+ + * | | | | | + * | PCI NTB | | | | + * | EPF | | | | + * | Driver | | | PCI Virtual | + * | | +---------------+ | NTB Driver | + * | | | PCI EP NTB |<------>| | + * | | | FN Driver | | | + * +------------+ +---------------+ +--------------+ + * | | | | | | + * | PCI Bus | <-----> | PCI EP Bus | | Virtual PCI | + * | | PCI | | | Bus | + * +------------+ +---------------+--------+--------------+ + * PCIe Root Port PCI EP + */ + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/slab.h> + +#include <linux/pci-epc.h> +#include <linux/pci-epf.h> +#include <linux/ntb.h> + +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_DB, + BAR_MW0, + BAR_MW1, + BAR_MW2, +}; + +/* + * +--------------------------------------------------+ Base + * | | + * | | + * | | + * | Common Control Register | + * | | + * | | + * | | + * +-----------------------+--------------------------+ Base+span_offset + * | | | + * | Peer Span Space | Span Space | + * | | | + * | | | + * +-----------------------+--------------------------+ Base+span_offset + * | | | +span_count * 4 + * | | | + * | Span Space | Peer Span Space | + * | | | + * +-----------------------+--------------------------+ + * Virtual PCI PCIe Endpoint + * NTB Driver NTB Driver + */ +struct epf_ntb_ctrl { + u32 command; + u32 argument; + u16 command_status; + u16 link_status; + u32 topology; + u64 addr; + u64 size; + u32 num_mws; + u32 reserved; + u32 spad_offset; + u32 spad_count; + u32 db_entry_size; + u32 db_data[MAX_DB_COUNT]; + u32 db_offset[MAX_DB_COUNT]; +} __packed; + +struct epf_ntb { + struct ntb_dev ntb; + struct pci_epf *epf; + struct config_group group; + + u32 num_mws; + u32 db_count; + u32 spad_count; + u64 mws_size[MAX_MW]; + u64 db; + u32 vbus_number; + u16 vntb_pid; + u16 vntb_vid; + + bool linkup; + u32 spad_size; + + enum pci_barno epf_ntb_bar[6]; + + struct epf_ntb_ctrl *reg; + + phys_addr_t epf_db_phy; + void __iomem *epf_db; + + phys_addr_t vpci_mw_phy[MAX_MW]; + void __iomem *vpci_mw_addr[MAX_MW]; + + struct delayed_work cmd_handler; +}; + +#define to_epf_ntb(epf_group) container_of((epf_group), struct epf_ntb, group) +#define ntb_ndev(__ntb) container_of(__ntb, struct epf_ntb, ntb) + +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 Virtual Host + * @ntb: NTB device that facilitates communication between HOST and VHOST + * @link_up: true or false indicating Link is UP or Down + * + * Once NTB function in HOST invoke ntb_link_enable(), + * this NTB function driver will trigger a link event to vhost. + */ +static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up) +{ + if (link_up) + ntb->reg->link_status |= LINK_STATUS_UP; + else + ntb->reg->link_status &= ~LINK_STATUS_UP; + + ntb_link_event(&ntb->ntb); + return 0; +} + +/** + * epf_ntb_configure_mw() - Configure the Outbound Address Space for vhost + * to access the memory window of host + * @ntb: NTB device that facilitates communication between host and vhost + * @mw: Index of the memory window (either 0, 1, 2 or 3) + * + * EP Outbound Window + * +--------+ +-----------+ + * | | | | + * | | | | + * | | | | + * | | | | + * | | +-----------+ + * | Virtual| | Memory Win| + * | NTB | -----------> | | + * | Driver | | | + * | | +-----------+ + * | | | | + * | | | | + * +--------+ +-----------+ + * VHost PCI EP + */ +static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw) +{ + phys_addr_t phys_addr; + u8 func_no, vfunc_no; + u64 addr, size; + int ret = 0; + + phys_addr = ntb->vpci_mw_phy[mw]; + addr = ntb->reg->addr; + size = ntb->reg->size; + + func_no = ntb->epf->func_no; + vfunc_no = ntb->epf->vfunc_no; + + ret = pci_epc_map_addr(ntb->epf->epc, func_no, vfunc_no, phys_addr, addr, size); + if (ret) + dev_err(&ntb->epf->epc->dev, + "Failed to map memory window %d address\n", mw); + return ret; +} + +/** + * epf_ntb_teardown_mw() - Teardown the configured OB ATU + * @ntb: NTB device that facilitates communication between HOST and vHOST + * @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, u32 mw) +{ + pci_epc_unmap_addr(ntb->epf->epc, + ntb->epf->func_no, + ntb->epf->vfunc_no, + ntb->vpci_mw_phy[mw]); +} + +/** + * epf_ntb_cmd_handler() - Handle commands provided by the NTB Host + * @work: work_struct for the epf_ntb_epc + * + * 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) +{ + struct epf_ntb_ctrl *ctrl; + u32 command, argument; + struct epf_ntb *ntb; + struct device *dev; + int ret; + int i; + + ntb = container_of(work, struct epf_ntb, cmd_handler.work); + + for (i = 1; i < ntb->db_count; i++) { + if (readl(ntb->epf_db + i * 4)) { + if (readl(ntb->epf_db + i * 4)) + ntb->db |= 1 << (i - 1); + + ntb_db_event(&ntb->ntb, i); + writel(0, ntb->epf_db + i * 4); + } + } + + ctrl = ntb->reg; + command = ctrl->command; + if (!command) + goto reset_handler; + argument = ctrl->argument; + + ctrl->command = 0; + ctrl->argument = 0; + + ctrl = ntb->reg; + dev = &ntb->epf->dev; + + switch (command) { + case COMMAND_CONFIGURE_DOORBELL: + ctrl->command_status = COMMAND_STATUS_OK; + break; + case COMMAND_TEARDOWN_DOORBELL: + ctrl->command_status = COMMAND_STATUS_OK; + break; + case COMMAND_CONFIGURE_MW: + ret = epf_ntb_configure_mw(ntb, 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, argument); + ctrl->command_status = COMMAND_STATUS_OK; + break; + case COMMAND_LINK_UP: + ntb->linkup = true; + 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; + case COMMAND_LINK_DOWN: + ntb->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, "UNKNOWN command: %d\n", command); + break; + } + +reset_handler: + queue_delayed_work(kpcintb_workqueue, &ntb->cmd_handler, + msecs_to_jiffies(5)); +} + +/** + * 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. + * + * 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 *ntb) +{ + struct pci_epf_bar *epf_bar; + enum pci_barno barno; + + barno = ntb->epf_ntb_bar[BAR_CONFIG]; + epf_bar = &ntb->epf->bar[barno]; + + pci_epc_clear_bar(ntb->epf->epc, ntb->epf->func_no, ntb->epf->vfunc_no, epf_bar); +} + +/** + * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR + * @ntb: NTB device that facilitates communication between HOST and vHOST + * + * Map BAR0 of EP CONTROLLER 1 which contains the HOST1's config and + * self scratchpad region. + * + * Please note the self scratchpad region and config region is combined to + * a single region and mapped using the same BAR. + */ +static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb) +{ + struct pci_epf_bar *epf_bar; + enum pci_barno barno; + u8 func_no, vfunc_no; + struct device *dev; + int ret; + + dev = &ntb->epf->dev; + func_no = ntb->epf->func_no; + vfunc_no = ntb->epf->vfunc_no; + barno = ntb->epf_ntb_bar[BAR_CONFIG]; + epf_bar = &ntb->epf->bar[barno]; + + ret = pci_epc_set_bar(ntb->epf->epc, func_no, vfunc_no, epf_bar); + if (ret) { + dev_err(dev, "inft: Config/Status/SPAD BAR set failed\n"); + 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 HOST and vHOST + */ +static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb) +{ + enum pci_barno barno; + + barno = ntb->epf_ntb_bar[BAR_CONFIG]; + pci_epf_free_space(ntb->epf, ntb->reg, barno, 0); +} + +/** + * epf_ntb_config_spad_bar_alloc() - Allocate memory for config + scratchpad + * region + * @ntb: NTB device that facilitates communication between HOST1 and HOST2 + * + * 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. + */ +static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb) +{ + size_t align; + enum pci_barno barno; + struct epf_ntb_ctrl *ctrl; + u32 spad_size, ctrl_size; + u64 size; + struct pci_epf *epf = ntb->epf; + struct device *dev = &epf->dev; + u32 spad_count; + void *base; + int i; + const struct pci_epc_features *epc_features = pci_epc_get_features(epf->epc, + epf->func_no, + epf->vfunc_no); + barno = ntb->epf_ntb_bar[BAR_CONFIG]; + size = epc_features->bar_fixed_size[barno]; + align = epc_features->align; + + if ((!IS_ALIGNED(size, align))) + return -EINVAL; + + spad_count = ntb->spad_count; + + ctrl_size = sizeof(struct epf_ntb_ctrl); + spad_size = 2 * spad_count * 4; + + 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 (!size) + size = ctrl_size + spad_size; + else if (size < ctrl_size + spad_size) + return -EINVAL; + + base = pci_epf_alloc_space(epf, size, barno, align, 0); + if (!base) { + dev_err(dev, "Config/Status/SPAD alloc region fail\n"); + return -ENOMEM; + } + + ntb->reg = base; + + ctrl = ntb->reg; + ctrl->spad_offset = ctrl_size; + + ctrl->spad_count = spad_count; + ctrl->num_mws = ntb->num_mws; + ntb->spad_size = spad_size; + + ctrl->db_entry_size = 4; + + for (i = 0; i < ntb->db_count; i++) { + ntb->reg->db_data[i] = 1 + i; + ntb->reg->db_offset[i] = 0; + } + + return 0; +} + +/** + * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capaiblity + * @ntb: NTB device that facilitates communication between HOST and vHOST + * + * 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) +{ + const struct pci_epc_features *epc_features; + struct device *dev; + u32 db_count; + int ret; + + dev = &ntb->epf->dev; + + epc_features = pci_epc_get_features(ntb->epf->epc, ntb->epf->func_no, ntb->epf->vfunc_no); + + if (!(epc_features->msix_capable || epc_features->msi_capable)) { + dev_err(dev, "MSI or MSI-X is required for doorbell\n"); + return -EINVAL; + } + + 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; + + if (epc_features->msi_capable) { + ret = pci_epc_set_msi(ntb->epf->epc, + ntb->epf->func_no, + ntb->epf->vfunc_no, + 16); + if (ret) { + dev_err(dev, "MSI configuration failed\n"); + return ret; + } + } + + return 0; +} + +/** + * epf_ntb_db_bar_init() - Configure Doorbell window BARs + * @ntb: NTB device that facilitates communication between HOST and vHOST + */ +static int epf_ntb_db_bar_init(struct epf_ntb *ntb) +{ + const struct pci_epc_features *epc_features; + u32 align; + struct device *dev = &ntb->epf->dev; + int ret; + struct pci_epf_bar *epf_bar; + void __iomem *mw_addr; + enum pci_barno barno; + size_t size = 4 * ntb->db_count; + + epc_features = pci_epc_get_features(ntb->epf->epc, + ntb->epf->func_no, + ntb->epf->vfunc_no); + align = epc_features->align; + + if (size < 128) + size = 128; + + if (align) + size = ALIGN(size, align); + else + size = roundup_pow_of_two(size); + + barno = ntb->epf_ntb_bar[BAR_DB]; + + mw_addr = pci_epf_alloc_space(ntb->epf, size, barno, align, 0); + if (!mw_addr) { + dev_err(dev, "Failed to allocate OB address\n"); + return -ENOMEM; + } + + ntb->epf_db = mw_addr; + + epf_bar = &ntb->epf->bar[barno]; + + ret = pci_epc_set_bar(ntb->epf->epc, ntb->epf->func_no, ntb->epf->vfunc_no, epf_bar); + if (ret) { + dev_err(dev, "Doorbell BAR set failed\n"); + goto err_alloc_peer_mem; + } + return ret; + +err_alloc_peer_mem: + pci_epc_mem_free_addr(ntb->epf->epc, epf_bar->phys_addr, mw_addr, epf_bar->size); + return -1; +} + +/** + * epf_ntb_db_bar_clear() - Clear doorbell BAR and free memory + * allocated in peer's outbound address space + * @ntb: NTB device that facilitates communication between HOST and vHOST + */ +static void epf_ntb_db_bar_clear(struct epf_ntb *ntb) +{ + enum pci_barno barno; + + barno = ntb->epf_ntb_bar[BAR_DB]; + pci_epf_free_space(ntb->epf, ntb->epf_db, barno, 0); + pci_epc_clear_bar(ntb->epf->epc, + ntb->epf->func_no, + ntb->epf->vfunc_no, + &ntb->epf->bar[barno]); +} + +/** + * epf_ntb_mw_bar_init() - Configure Memory window BARs + * @ntb: NTB device that facilitates communication between HOST and vHOST + * + */ +static int epf_ntb_mw_bar_init(struct epf_ntb *ntb) +{ + int ret = 0; + int i; + u64 size; + enum pci_barno barno; + struct device *dev = &ntb->epf->dev; + + for (i = 0; i < ntb->num_mws; i++) { + size = ntb->mws_size[i]; + barno = ntb->epf_ntb_bar[BAR_MW0 + i]; + + ntb->epf->bar[barno].barno = barno; + ntb->epf->bar[barno].size = size; + ntb->epf->bar[barno].addr = 0; + ntb->epf->bar[barno].phys_addr = 0; + ntb->epf->bar[barno].flags |= upper_32_bits(size) ? + PCI_BASE_ADDRESS_MEM_TYPE_64 : + PCI_BASE_ADDRESS_MEM_TYPE_32; + + ret = pci_epc_set_bar(ntb->epf->epc, + ntb->epf->func_no, + ntb->epf->vfunc_no, + &ntb->epf->bar[barno]); + if (ret) { + dev_err(dev, "MW set failed\n"); + goto err_alloc_mem; + } + + /* Allocate EPC outbound memory windows to vpci vntb device */ + ntb->vpci_mw_addr[i] = pci_epc_mem_alloc_addr(ntb->epf->epc, + &ntb->vpci_mw_phy[i], + size); + if (!ntb->vpci_mw_addr[i]) { + dev_err(dev, "Failed to allocate source address\n"); + goto err_alloc_mem; + } + } + + return ret; +err_alloc_mem: + return ret; +} + +/** + * epf_ntb_mw_bar_clear() - Clear Memory window BARs + * @ntb: NTB device that facilitates communication between HOST and vHOST + */ +static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb) +{ + enum pci_barno barno; + int i; + + for (i = 0; i < ntb->num_mws; i++) { + barno = ntb->epf_ntb_bar[BAR_MW0 + i]; + pci_epc_clear_bar(ntb->epf->epc, + ntb->epf->func_no, + ntb->epf->vfunc_no, + &ntb->epf->bar[barno]); + + pci_epc_mem_free_addr(ntb->epf->epc, + ntb->vpci_mw_phy[i], + ntb->vpci_mw_addr[i], + ntb->mws_size[i]); + } +} + +/** + * epf_ntb_epc_destroy() - Cleanup NTB EPC interface + * @ntb: NTB device that facilitates communication between HOST and vHOST + * + * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB interfaces + */ +static void epf_ntb_epc_destroy(struct epf_ntb *ntb) +{ + pci_epc_remove_epf(ntb->epf->epc, ntb->epf, 0); + pci_epc_put(ntb->epf->epc); +} + +/** + * 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 HOST and vHOST + */ +static int epf_ntb_init_epc_bar(struct epf_ntb *ntb) +{ + const struct pci_epc_features *epc_features; + enum pci_barno barno; + enum epf_ntb_bar bar; + struct device *dev; + u32 num_mws; + int i; + + barno = BAR_0; + num_mws = ntb->num_mws; + dev = &ntb->epf->dev; + epc_features = pci_epc_get_features(ntb->epf->epc, ntb->epf->func_no, ntb->epf->vfunc_no); + + /* These are required BARs which are mandatory for NTB functionality */ + for (bar = BAR_CONFIG; bar <= BAR_MW0; bar++, barno++) { + barno = pci_epc_get_next_free_bar(epc_features, barno); + if (barno < 0) { + dev_err(dev, "Fail to get NTB function BAR\n"); + return barno; + } + ntb->epf_ntb_bar[bar] = barno; + } + + /* These are optional BARs which don't impact NTB functionality */ + for (bar = BAR_MW1, 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->epf_ntb_bar[bar] = barno; + } + + return 0; +} + +/** + * epf_ntb_epc_init() - Initialize NTB interface + * @ntb: NTB device that facilitates communication between HOST and vHOST2 + * + * 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(struct epf_ntb *ntb) +{ + u8 func_no, vfunc_no; + struct pci_epc *epc; + struct pci_epf *epf; + struct device *dev; + int ret; + + epf = ntb->epf; + dev = &epf->dev; + epc = epf->epc; + func_no = ntb->epf->func_no; + vfunc_no = ntb->epf->vfunc_no; + + ret = epf_ntb_config_sspad_bar_set(ntb); + if (ret) { + dev_err(dev, "Config/self SPAD BAR init failed"); + return ret; + } + + ret = epf_ntb_configure_interrupt(ntb); + if (ret) { + dev_err(dev, "Interrupt configuration failed\n"); + goto err_config_interrupt; + } + + ret = epf_ntb_db_bar_init(ntb); + if (ret) { + dev_err(dev, "DB BAR init failed\n"); + goto err_db_bar_init; + } + + ret = epf_ntb_mw_bar_init(ntb); + if (ret) { + dev_err(dev, "MW BAR init failed\n"); + goto err_mw_bar_init; + } + + if (vfunc_no <= 1) { + ret = pci_epc_write_header(epc, func_no, vfunc_no, epf->header); + if (ret) { + dev_err(dev, "Configuration header write failed\n"); + goto err_write_header; + } + } + + INIT_DELAYED_WORK(&ntb->cmd_handler, epf_ntb_cmd_handler); + queue_work(kpcintb_workqueue, &ntb->cmd_handler.work); + + return 0; + +err_write_header: + epf_ntb_mw_bar_clear(ntb); +err_mw_bar_init: + epf_ntb_db_bar_clear(ntb); +err_db_bar_init: +err_config_interrupt: + epf_ntb_config_sspad_bar_clear(ntb); + + return ret; +} + + +/** + * 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) +{ + epf_ntb_db_bar_clear(ntb); + epf_ntb_mw_bar_clear(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 sprintf(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; \ + int ret; \ + \ + ret = kstrtou32(page, 0, &val); \ + if (ret) \ + return ret; \ + \ + 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 sprintf(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; \ + int ret; \ + \ + ret = kstrtou64(page, 0, &val); \ + if (ret) \ + return ret; \ + \ + 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; + int ret; + + ret = kstrtou32(page, 0, &val); + if (ret) + return ret; + + 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_R(vbus_number) +EPF_NTB_W(vbus_number) +EPF_NTB_R(vntb_pid) +EPF_NTB_W(vntb_pid) +EPF_NTB_R(vntb_vid) +EPF_NTB_W(vntb_vid) +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); +CONFIGFS_ATTR(epf_ntb_, vbus_number); +CONFIGFS_ATTR(epf_ntb_, vntb_pid); +CONFIGFS_ATTR(epf_ntb_, vntb_vid); + +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, + &epf_ntb_attr_vbus_number, + &epf_ntb_attr_vntb_pid, + &epf_ntb_attr_vntb_vid, + 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; +} + +/*==== virtual PCI bus driver, which only load virtual NTB PCI driver ====*/ + +static u32 pci_space[] = { + 0xffffffff, /*DeviceID, Vendor ID*/ + 0, /*Status, Command*/ + 0xffffffff, /*Class code, subclass, prog if, revision id*/ + 0x40, /*bist, header type, latency Timer, cache line size*/ + 0, /*BAR 0*/ + 0, /*BAR 1*/ + 0, /*BAR 2*/ + 0, /*BAR 3*/ + 0, /*BAR 4*/ + 0, /*BAR 5*/ + 0, /*Cardbus cis point*/ + 0, /*Subsystem ID Subystem vendor id*/ + 0, /*ROM Base Address*/ + 0, /*Reserved, Cap. Point*/ + 0, /*Reserved,*/ + 0, /*Max Lat, Min Gnt, interrupt pin, interrupt line*/ +}; + +int pci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val) +{ + if (devfn == 0) { + memcpy(val, ((u8 *)pci_space) + where, size); + return PCIBIOS_SUCCESSFUL; + } + return PCIBIOS_DEVICE_NOT_FOUND; +} + +int pci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val) +{ + return 0; +} + +struct pci_ops vpci_ops = { + .read = pci_read, + .write = pci_write, +}; + +static int vpci_scan_bus(void *sysdata) +{ + struct pci_bus *vpci_bus; + struct epf_ntb *ndev = sysdata; + + vpci_bus = pci_scan_bus(ndev->vbus_number, &vpci_ops, sysdata); + if (vpci_bus) + pr_err("create pci bus\n"); + + pci_bus_add_devices(vpci_bus); + + return 0; +} + +/*==================== Virtual PCIe NTB driver ==========================*/ + +static int vntb_epf_mw_count(struct ntb_dev *ntb, int pidx) +{ + struct epf_ntb *ndev = ntb_ndev(ntb); + + return ndev->num_mws; +} + +static int vntb_epf_spad_count(struct ntb_dev *ntb) +{ + return ntb_ndev(ntb)->spad_count; +} + +static int vntb_epf_peer_mw_count(struct ntb_dev *ntb) +{ + return ntb_ndev(ntb)->num_mws; +} + +static u64 vntb_epf_db_valid_mask(struct ntb_dev *ntb) +{ + return BIT_ULL(ntb_ndev(ntb)->db_count) - 1; +} + +static int vntb_epf_db_set_mask(struct ntb_dev *ntb, u64 db_bits) +{ + return 0; +} + +static int vntb_epf_mw_set_trans(struct ntb_dev *ndev, int pidx, int idx, + dma_addr_t addr, resource_size_t size) +{ + struct epf_ntb *ntb = ntb_ndev(ndev); + struct pci_epf_bar *epf_bar; + enum pci_barno barno; + int ret; + struct device *dev; + + dev = &ntb->ntb.dev; + barno = ntb->epf_ntb_bar[BAR_MW0 + idx]; + epf_bar = &ntb->epf->bar[barno]; + epf_bar->phys_addr = addr; + epf_bar->barno = barno; + epf_bar->size = size; + + ret = pci_epc_set_bar(ntb->epf->epc, 0, 0, epf_bar); + if (ret) { + dev_err(dev, "failure set mw trans\n"); + return ret; + } + return 0; +} + +static int vntb_epf_mw_clear_trans(struct ntb_dev *ntb, int pidx, int idx) +{ + return 0; +} + +static int vntb_epf_peer_mw_get_addr(struct ntb_dev *ndev, int idx, + phys_addr_t *base, resource_size_t *size) +{ + + struct epf_ntb *ntb = ntb_ndev(ndev); + + if (base) + *base = ntb->vpci_mw_phy[idx]; + + if (size) + *size = ntb->mws_size[idx]; + + return 0; +} + +static int vntb_epf_link_enable(struct ntb_dev *ntb, + enum ntb_speed max_speed, + enum ntb_width max_width) +{ + return 0; +} + +static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx) +{ + struct epf_ntb *ntb = ntb_ndev(ndev); + int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * 4; + u32 val; + void __iomem *base = ntb->reg; + + val = readl(base + off + ct + idx * 4); + return val; +} + +static int vntb_epf_spad_write(struct ntb_dev *ndev, int idx, u32 val) +{ + struct epf_ntb *ntb = ntb_ndev(ndev); + struct epf_ntb_ctrl *ctrl = ntb->reg; + int off = ctrl->spad_offset, ct = ctrl->spad_count * 4; + void __iomem *base = ntb->reg; + + writel(val, base + off + ct + idx * 4); + return 0; +} + +static u32 vntb_epf_peer_spad_read(struct ntb_dev *ndev, int pidx, int idx) +{ + struct epf_ntb *ntb = ntb_ndev(ndev); + struct epf_ntb_ctrl *ctrl = ntb->reg; + int off = ctrl->spad_offset; + void __iomem *base = ntb->reg; + u32 val; + + val = readl(base + off + idx * 4); + return val; +} + +static int vntb_epf_peer_spad_write(struct ntb_dev *ndev, int pidx, int idx, u32 val) +{ + struct epf_ntb *ntb = ntb_ndev(ndev); + struct epf_ntb_ctrl *ctrl = ntb->reg; + int off = ctrl->spad_offset; + void __iomem *base = ntb->reg; + + writel(val, base + off + idx * 4); + return 0; +} + +static int vntb_epf_peer_db_set(struct ntb_dev *ndev, u64 db_bits) +{ + u32 interrupt_num = ffs(db_bits) + 1; + struct epf_ntb *ntb = ntb_ndev(ndev); + u8 func_no, vfunc_no; + int ret; + + func_no = ntb->epf->func_no; + vfunc_no = ntb->epf->vfunc_no; + + ret = pci_epc_raise_irq(ntb->epf->epc, + func_no, + vfunc_no, + PCI_EPC_IRQ_MSI, + interrupt_num + 1); + if (ret) + dev_err(&ntb->ntb.dev, "Failed to raise IRQ\n"); + + return ret; +} + +static u64 vntb_epf_db_read(struct ntb_dev *ndev) +{ + struct epf_ntb *ntb = ntb_ndev(ndev); + + return ntb->db; +} + +static int vntb_epf_mw_get_align(struct ntb_dev *ndev, int pidx, int idx, + resource_size_t *addr_align, + resource_size_t *size_align, + resource_size_t *size_max) +{ + struct epf_ntb *ntb = ntb_ndev(ndev); + + if (addr_align) + *addr_align = SZ_4K; + + if (size_align) + *size_align = 1; + + if (size_max) + *size_max = ntb->mws_size[idx]; + + return 0; +} + +static u64 vntb_epf_link_is_up(struct ntb_dev *ndev, + enum ntb_speed *speed, + enum ntb_width *width) +{ + struct epf_ntb *ntb = ntb_ndev(ndev); + + return ntb->reg->link_status; +} + +static int vntb_epf_db_clear_mask(struct ntb_dev *ndev, u64 db_bits) +{ + return 0; +} + +static int vntb_epf_db_clear(struct ntb_dev *ndev, u64 db_bits) +{ + struct epf_ntb *ntb = ntb_ndev(ndev); + + ntb->db &= ~db_bits; + return 0; +} + +static int vntb_epf_link_disable(struct ntb_dev *ntb) +{ + return 0; +} + +static const struct ntb_dev_ops vntb_epf_ops = { + .mw_count = vntb_epf_mw_count, + .spad_count = vntb_epf_spad_count, + .peer_mw_count = vntb_epf_peer_mw_count, + .db_valid_mask = vntb_epf_db_valid_mask, + .db_set_mask = vntb_epf_db_set_mask, + .mw_set_trans = vntb_epf_mw_set_trans, + .mw_clear_trans = vntb_epf_mw_clear_trans, + .peer_mw_get_addr = vntb_epf_peer_mw_get_addr, + .link_enable = vntb_epf_link_enable, + .spad_read = vntb_epf_spad_read, + .spad_write = vntb_epf_spad_write, + .peer_spad_read = vntb_epf_peer_spad_read, + .peer_spad_write = vntb_epf_peer_spad_write, + .peer_db_set = vntb_epf_peer_db_set, + .db_read = vntb_epf_db_read, + .mw_get_align = vntb_epf_mw_get_align, + .link_is_up = vntb_epf_link_is_up, + .db_clear_mask = vntb_epf_db_clear_mask, + .db_clear = vntb_epf_db_clear, + .link_disable = vntb_epf_link_disable, +}; + +static int pci_vntb_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ + int ret; + struct epf_ntb *ndev = (struct epf_ntb *)pdev->sysdata; + struct device *dev = &pdev->dev; + + ndev->ntb.pdev = pdev; + ndev->ntb.topo = NTB_TOPO_NONE; + ndev->ntb.ops = &vntb_epf_ops; + + ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32)); + if (ret) { + dev_err(dev, "Cannot set DMA mask\n"); + return -EINVAL; + } + + ret = ntb_register_device(&ndev->ntb); + if (ret) { + dev_err(dev, "Failed to register NTB device\n"); + goto err_register_dev; + } + + dev_dbg(dev, "PCI Virtual NTB driver loaded\n"); + return 0; + +err_register_dev: + return -EINVAL; +} + +static struct pci_device_id pci_vntb_table[] = { + { + PCI_DEVICE(0xffff, 0xffff), + }, + {}, +}; + +static struct pci_driver vntb_pci_driver = { + .name = "pci-vntb", + .id_table = pci_vntb_table, + .probe = pci_vntb_probe, +}; + +/* ============ PCIe EPF Driver Bind ====================*/ + +/** + * 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; + } + + 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(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); + + pci_space[0] = (ntb->vntb_pid << 16) | ntb->vntb_vid; + pci_vntb_table[0].vendor = ntb->vntb_vid; + pci_vntb_table[0].device = ntb->vntb_pid; + + if (pci_register_driver(&vntb_pci_driver)) { + dev_err(dev, "failure register vntb pci driver\n"); + goto err_bar_alloc; + } + + vpci_scan_bus(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); + + pci_unregister_driver(&vntb_pci_driver); +} + +// EPF driver probe +static struct pci_epf_ops epf_ntb_ops = { + .bind = epf_ntb_bind, + .unbind = epf_ntb_unbind, + .add_cfs = epf_ntb_add_cfs, +}; + +/** + * epf_ntb_probe() - Probe NTB function driver + * @epf: NTB endpoint function device + * + * Probe NTB function driver when endpoint function bus detects a NTB + * endpoint function. + */ +static int epf_ntb_probe(struct pci_epf *epf) +{ + 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; + ntb->vbus_number = 0xff; + epf_set_drvdata(epf, ntb); + + dev_info(dev, "pci-ep epf driver loaded\n"); + return 0; +} + +static const struct pci_epf_device_id epf_ntb_ids[] = { + { + .name = "pci_epf_vntb", + }, + {}, +}; + +static struct pci_epf_driver epf_ntb_driver = { + .driver.name = "pci_epf_vntb", + .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("Frank Li <Frank.li@xxxxxxx>"); +MODULE_LICENSE("GPL v2"); -- 2.43.0