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1// SPDX-License-Identifier: GPL-2.02/*3 * Endpoint Function Driver to implement Non-Transparent Bridge functionality4 * Between PCI RC and EP5 *6 * Copyright (C) 2020 Texas Instruments7 * Copyright (C) 2022 NXP8 *9 * Based on pci-epf-ntb.c10 * Author: Frank Li <Frank.Li@nxp.com>11 * Author: Kishon Vijay Abraham I <kishon@ti.com>12 */13 14/*15 * +------------+         +---------------------------------------+16 * |            |         |                                       |17 * +------------+         |                        +--------------+18 * | NTB        |         |                        | NTB          |19 * | NetDev     |         |                        | NetDev       |20 * +------------+         |                        +--------------+21 * | NTB        |         |                        | NTB          |22 * | Transfer   |         |                        | Transfer     |23 * +------------+         |                        +--------------+24 * |            |         |                        |              |25 * |  PCI NTB   |         |                        |              |26 * |    EPF     |         |                        |              |27 * |   Driver   |         |                        | PCI Virtual  |28 * |            |         +---------------+        | NTB Driver   |29 * |            |         | PCI EP NTB    |<------>|              |30 * |            |         |  FN Driver    |        |              |31 * +------------+         +---------------+        +--------------+32 * |            |         |               |        |              |33 * |  PCI Bus   | <-----> |  PCI EP Bus   |        |  Virtual PCI |34 * |            |  PCI    |               |        |     Bus      |35 * +------------+         +---------------+--------+--------------+36 * PCIe Root Port                        PCI EP37 */38 39#include <linux/delay.h>40#include <linux/io.h>41#include <linux/module.h>42#include <linux/slab.h>43 44#include <linux/pci-epc.h>45#include <linux/pci-epf.h>46#include <linux/ntb.h>47 48static struct workqueue_struct *kpcintb_workqueue;49 50#define COMMAND_CONFIGURE_DOORBELL	151#define COMMAND_TEARDOWN_DOORBELL	252#define COMMAND_CONFIGURE_MW		353#define COMMAND_TEARDOWN_MW		454#define COMMAND_LINK_UP			555#define COMMAND_LINK_DOWN		656 57#define COMMAND_STATUS_OK		158#define COMMAND_STATUS_ERROR		259 60#define LINK_STATUS_UP			BIT(0)61 62#define SPAD_COUNT			6463#define DB_COUNT			464#define NTB_MW_OFFSET			265#define DB_COUNT_MASK			GENMASK(15, 0)66#define MSIX_ENABLE			BIT(16)67#define MAX_DB_COUNT			3268#define MAX_MW				469 70enum epf_ntb_bar {71	BAR_CONFIG,72	BAR_DB,73	BAR_MW0,74	BAR_MW1,75	BAR_MW2,76};77 78/*79 * +--------------------------------------------------+ Base80 * |                                                  |81 * |                                                  |82 * |                                                  |83 * |          Common Control Register                 |84 * |                                                  |85 * |                                                  |86 * |                                                  |87 * +-----------------------+--------------------------+ Base+spad_offset88 * |                       |                          |89 * |    Peer Spad Space    |    Spad Space            |90 * |                       |                          |91 * |                       |                          |92 * +-----------------------+--------------------------+ Base+spad_offset93 * |                       |                          |     +spad_count * 494 * |                       |                          |95 * |     Spad Space        |   Peer Spad Space        |96 * |                       |                          |97 * +-----------------------+--------------------------+98 *       Virtual PCI             PCIe Endpoint99 *       NTB Driver               NTB Driver100 */101struct epf_ntb_ctrl {102	u32 command;103	u32 argument;104	u16 command_status;105	u16 link_status;106	u32 topology;107	u64 addr;108	u64 size;109	u32 num_mws;110	u32 reserved;111	u32 spad_offset;112	u32 spad_count;113	u32 db_entry_size;114	u32 db_data[MAX_DB_COUNT];115	u32 db_offset[MAX_DB_COUNT];116} __packed;117 118struct epf_ntb {119	struct ntb_dev ntb;120	struct pci_epf *epf;121	struct config_group group;122 123	u32 num_mws;124	u32 db_count;125	u32 spad_count;126	u64 mws_size[MAX_MW];127	u64 db;128	u32 vbus_number;129	u16 vntb_pid;130	u16 vntb_vid;131 132	bool linkup;133	u32 spad_size;134 135	enum pci_barno epf_ntb_bar[6];136 137	struct epf_ntb_ctrl *reg;138 139	u32 *epf_db;140 141	phys_addr_t vpci_mw_phy[MAX_MW];142	void __iomem *vpci_mw_addr[MAX_MW];143 144	struct delayed_work cmd_handler;145};146 147#define to_epf_ntb(epf_group) container_of((epf_group), struct epf_ntb, group)148#define ntb_ndev(__ntb) container_of(__ntb, struct epf_ntb, ntb)149 150static struct pci_epf_header epf_ntb_header = {151	.vendorid	= PCI_ANY_ID,152	.deviceid	= PCI_ANY_ID,153	.baseclass_code	= PCI_BASE_CLASS_MEMORY,154	.interrupt_pin	= PCI_INTERRUPT_INTA,155};156 157/**158 * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host (VHOST)159 * @ntb: NTB device that facilitates communication between HOST and VHOST160 * @link_up: true or false indicating Link is UP or Down161 *162 * Once NTB function in HOST invoke ntb_link_enable(),163 * this NTB function driver will trigger a link event to VHOST.164 *165 * Returns: Zero for success, or an error code in case of failure166 */167static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)168{169	if (link_up)170		ntb->reg->link_status |= LINK_STATUS_UP;171	else172		ntb->reg->link_status &= ~LINK_STATUS_UP;173 174	ntb_link_event(&ntb->ntb);175	return 0;176}177 178/**179 * epf_ntb_configure_mw() - Configure the Outbound Address Space for VHOST180 *   to access the memory window of HOST181 * @ntb: NTB device that facilitates communication between HOST and VHOST182 * @mw: Index of the memory window (either 0, 1, 2 or 3)183 *184 *                          EP Outbound Window185 * +--------+              +-----------+186 * |        |              |           |187 * |        |              |           |188 * |        |              |           |189 * |        |              |           |190 * |        |              +-----------+191 * | Virtual|              | Memory Win|192 * | NTB    | -----------> |           |193 * | Driver |              |           |194 * |        |              +-----------+195 * |        |              |           |196 * |        |              |           |197 * +--------+              +-----------+198 *  VHOST                   PCI EP199 *200 * Returns: Zero for success, or an error code in case of failure201 */202static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)203{204	phys_addr_t phys_addr;205	u8 func_no, vfunc_no;206	u64 addr, size;207	int ret = 0;208 209	phys_addr = ntb->vpci_mw_phy[mw];210	addr = ntb->reg->addr;211	size = ntb->reg->size;212 213	func_no = ntb->epf->func_no;214	vfunc_no = ntb->epf->vfunc_no;215 216	ret = pci_epc_map_addr(ntb->epf->epc, func_no, vfunc_no, phys_addr, addr, size);217	if (ret)218		dev_err(&ntb->epf->epc->dev,219			"Failed to map memory window %d address\n", mw);220	return ret;221}222 223/**224 * epf_ntb_teardown_mw() - Teardown the configured OB ATU225 * @ntb: NTB device that facilitates communication between HOST and VHOST226 * @mw: Index of the memory window (either 0, 1, 2 or 3)227 *228 * Teardown the configured OB ATU configured in epf_ntb_configure_mw() using229 * pci_epc_unmap_addr()230 */231static void epf_ntb_teardown_mw(struct epf_ntb *ntb, u32 mw)232{233	pci_epc_unmap_addr(ntb->epf->epc,234			   ntb->epf->func_no,235			   ntb->epf->vfunc_no,236			   ntb->vpci_mw_phy[mw]);237}238 239/**240 * epf_ntb_cmd_handler() - Handle commands provided by the NTB HOST241 * @work: work_struct for the epf_ntb_epc242 *243 * Workqueue function that gets invoked for the two epf_ntb_epc244 * periodically (once every 5ms) to see if it has received any commands245 * from NTB HOST. The HOST can send commands to configure doorbell or246 * configure memory window or to update link status.247 */248static void epf_ntb_cmd_handler(struct work_struct *work)249{250	struct epf_ntb_ctrl *ctrl;251	u32 command, argument;252	struct epf_ntb *ntb;253	struct device *dev;254	int ret;255	int i;256 257	ntb = container_of(work, struct epf_ntb, cmd_handler.work);258 259	for (i = 1; i < ntb->db_count; i++) {260		if (ntb->epf_db[i]) {261			ntb->db |= 1 << (i - 1);262			ntb_db_event(&ntb->ntb, i);263			ntb->epf_db[i] = 0;264		}265	}266 267	ctrl = ntb->reg;268	command = ctrl->command;269	if (!command)270		goto reset_handler;271	argument = ctrl->argument;272 273	ctrl->command = 0;274	ctrl->argument = 0;275 276	ctrl = ntb->reg;277	dev = &ntb->epf->dev;278 279	switch (command) {280	case COMMAND_CONFIGURE_DOORBELL:281		ctrl->command_status = COMMAND_STATUS_OK;282		break;283	case COMMAND_TEARDOWN_DOORBELL:284		ctrl->command_status = COMMAND_STATUS_OK;285		break;286	case COMMAND_CONFIGURE_MW:287		ret = epf_ntb_configure_mw(ntb, argument);288		if (ret < 0)289			ctrl->command_status = COMMAND_STATUS_ERROR;290		else291			ctrl->command_status = COMMAND_STATUS_OK;292		break;293	case COMMAND_TEARDOWN_MW:294		epf_ntb_teardown_mw(ntb, argument);295		ctrl->command_status = COMMAND_STATUS_OK;296		break;297	case COMMAND_LINK_UP:298		ntb->linkup = true;299		ret = epf_ntb_link_up(ntb, true);300		if (ret < 0)301			ctrl->command_status = COMMAND_STATUS_ERROR;302		else303			ctrl->command_status = COMMAND_STATUS_OK;304		goto reset_handler;305	case COMMAND_LINK_DOWN:306		ntb->linkup = false;307		ret = epf_ntb_link_up(ntb, false);308		if (ret < 0)309			ctrl->command_status = COMMAND_STATUS_ERROR;310		else311			ctrl->command_status = COMMAND_STATUS_OK;312		break;313	default:314		dev_err(dev, "UNKNOWN command: %d\n", command);315		break;316	}317 318reset_handler:319	queue_delayed_work(kpcintb_workqueue, &ntb->cmd_handler,320			   msecs_to_jiffies(5));321}322 323/**324 * epf_ntb_config_sspad_bar_clear() - Clear Config + Self scratchpad BAR325 * @ntb: EPC associated with one of the HOST which holds peer's outbound326 *	 address.327 *328 * Clear BAR0 of EP CONTROLLER 1 which contains the HOST1's config and329 * self scratchpad region (removes inbound ATU configuration). While BAR0 is330 * the default self scratchpad BAR, an NTB could have other BARs for self331 * scratchpad (because of reserved BARs). This function can get the exact BAR332 * used for self scratchpad from epf_ntb_bar[BAR_CONFIG].333 *334 * Please note the self scratchpad region and config region is combined to335 * a single region and mapped using the same BAR. Also note VHOST's peer336 * scratchpad is HOST's self scratchpad.337 *338 * Returns: void339 */340static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)341{342	struct pci_epf_bar *epf_bar;343	enum pci_barno barno;344 345	barno = ntb->epf_ntb_bar[BAR_CONFIG];346	epf_bar = &ntb->epf->bar[barno];347 348	pci_epc_clear_bar(ntb->epf->epc, ntb->epf->func_no, ntb->epf->vfunc_no, epf_bar);349}350 351/**352 * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR353 * @ntb: NTB device that facilitates communication between HOST and VHOST354 *355 * Map BAR0 of EP CONTROLLER which contains the VHOST's config and356 * self scratchpad region.357 *358 * Please note the self scratchpad region and config region is combined to359 * a single region and mapped using the same BAR.360 *361 * Returns: Zero for success, or an error code in case of failure362 */363static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)364{365	struct pci_epf_bar *epf_bar;366	enum pci_barno barno;367	u8 func_no, vfunc_no;368	struct device *dev;369	int ret;370 371	dev = &ntb->epf->dev;372	func_no = ntb->epf->func_no;373	vfunc_no = ntb->epf->vfunc_no;374	barno = ntb->epf_ntb_bar[BAR_CONFIG];375	epf_bar = &ntb->epf->bar[barno];376 377	ret = pci_epc_set_bar(ntb->epf->epc, func_no, vfunc_no, epf_bar);378	if (ret) {379		dev_err(dev, "inft: Config/Status/SPAD BAR set failed\n");380		return ret;381	}382	return 0;383}384 385/**386 * epf_ntb_config_spad_bar_free() - Free the physical memory associated with387 *   config + scratchpad region388 * @ntb: NTB device that facilitates communication between HOST and VHOST389 */390static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)391{392	enum pci_barno barno;393 394	barno = ntb->epf_ntb_bar[BAR_CONFIG];395	pci_epf_free_space(ntb->epf, ntb->reg, barno, 0);396}397 398/**399 * epf_ntb_config_spad_bar_alloc() - Allocate memory for config + scratchpad400 *   region401 * @ntb: NTB device that facilitates communication between HOST and VHOST402 *403 * Allocate the Local Memory mentioned in the above diagram. The size of404 * CONFIG REGION is sizeof(struct epf_ntb_ctrl) and size of SCRATCHPAD REGION405 * is obtained from "spad-count" configfs entry.406 *407 * Returns: Zero for success, or an error code in case of failure408 */409static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)410{411	size_t align;412	enum pci_barno barno;413	struct epf_ntb_ctrl *ctrl;414	u32 spad_size, ctrl_size;415	u64 size;416	struct pci_epf *epf = ntb->epf;417	struct device *dev = &epf->dev;418	u32 spad_count;419	void *base;420	int i;421	const struct pci_epc_features *epc_features = pci_epc_get_features(epf->epc,422								epf->func_no,423								epf->vfunc_no);424	barno = ntb->epf_ntb_bar[BAR_CONFIG];425	size = epc_features->bar[barno].fixed_size;426	align = epc_features->align;427 428	if ((!IS_ALIGNED(size, align)))429		return -EINVAL;430 431	spad_count = ntb->spad_count;432 433	ctrl_size = sizeof(struct epf_ntb_ctrl);434	spad_size = 2 * spad_count * sizeof(u32);435 436	if (!align) {437		ctrl_size = roundup_pow_of_two(ctrl_size);438		spad_size = roundup_pow_of_two(spad_size);439	} else {440		ctrl_size = ALIGN(ctrl_size, align);441		spad_size = ALIGN(spad_size, align);442	}443 444	if (!size)445		size = ctrl_size + spad_size;446	else if (size < ctrl_size + spad_size)447		return -EINVAL;448 449	base = pci_epf_alloc_space(epf, size, barno, epc_features, 0);450	if (!base) {451		dev_err(dev, "Config/Status/SPAD alloc region fail\n");452		return -ENOMEM;453	}454 455	ntb->reg = base;456 457	ctrl = ntb->reg;458	ctrl->spad_offset = ctrl_size;459 460	ctrl->spad_count = spad_count;461	ctrl->num_mws = ntb->num_mws;462	ntb->spad_size = spad_size;463 464	ctrl->db_entry_size = sizeof(u32);465 466	for (i = 0; i < ntb->db_count; i++) {467		ntb->reg->db_data[i] = 1 + i;468		ntb->reg->db_offset[i] = 0;469	}470 471	return 0;472}473 474/**475 * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capability476 * @ntb: NTB device that facilitates communication between HOST and VHOST477 *478 * Configure MSI/MSI-X capability for each interface with number of479 * interrupts equal to "db_count" configfs entry.480 *481 * Returns: Zero for success, or an error code in case of failure482 */483static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)484{485	const struct pci_epc_features *epc_features;486	struct device *dev;487	u32 db_count;488	int ret;489 490	dev = &ntb->epf->dev;491 492	epc_features = pci_epc_get_features(ntb->epf->epc, ntb->epf->func_no, ntb->epf->vfunc_no);493 494	if (!(epc_features->msix_capable || epc_features->msi_capable)) {495		dev_err(dev, "MSI or MSI-X is required for doorbell\n");496		return -EINVAL;497	}498 499	db_count = ntb->db_count;500	if (db_count > MAX_DB_COUNT) {501		dev_err(dev, "DB count cannot be more than %d\n", MAX_DB_COUNT);502		return -EINVAL;503	}504 505	ntb->db_count = db_count;506 507	if (epc_features->msi_capable) {508		ret = pci_epc_set_msi(ntb->epf->epc,509				      ntb->epf->func_no,510				      ntb->epf->vfunc_no,511				      16);512		if (ret) {513			dev_err(dev, "MSI configuration failed\n");514			return ret;515		}516	}517 518	return 0;519}520 521/**522 * epf_ntb_db_bar_init() - Configure Doorbell window BARs523 * @ntb: NTB device that facilitates communication between HOST and VHOST524 *525 * Returns: Zero for success, or an error code in case of failure526 */527static int epf_ntb_db_bar_init(struct epf_ntb *ntb)528{529	const struct pci_epc_features *epc_features;530	struct device *dev = &ntb->epf->dev;531	int ret;532	struct pci_epf_bar *epf_bar;533	void __iomem *mw_addr;534	enum pci_barno barno;535	size_t size = sizeof(u32) * ntb->db_count;536 537	epc_features = pci_epc_get_features(ntb->epf->epc,538					    ntb->epf->func_no,539					    ntb->epf->vfunc_no);540	barno = ntb->epf_ntb_bar[BAR_DB];541 542	mw_addr = pci_epf_alloc_space(ntb->epf, size, barno, epc_features, 0);543	if (!mw_addr) {544		dev_err(dev, "Failed to allocate OB address\n");545		return -ENOMEM;546	}547 548	ntb->epf_db = mw_addr;549 550	epf_bar = &ntb->epf->bar[barno];551 552	ret = pci_epc_set_bar(ntb->epf->epc, ntb->epf->func_no, ntb->epf->vfunc_no, epf_bar);553	if (ret) {554		dev_err(dev, "Doorbell BAR set failed\n");555			goto err_alloc_peer_mem;556	}557	return ret;558 559err_alloc_peer_mem:560	pci_epf_free_space(ntb->epf, mw_addr, barno, 0);561	return -1;562}563 564static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb, int num_mws);565 566/**567 * epf_ntb_db_bar_clear() - Clear doorbell BAR and free memory568 *   allocated in peer's outbound address space569 * @ntb: NTB device that facilitates communication between HOST and VHOST570 */571static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)572{573	enum pci_barno barno;574 575	barno = ntb->epf_ntb_bar[BAR_DB];576	pci_epf_free_space(ntb->epf, ntb->epf_db, barno, 0);577	pci_epc_clear_bar(ntb->epf->epc,578			  ntb->epf->func_no,579			  ntb->epf->vfunc_no,580			  &ntb->epf->bar[barno]);581}582 583/**584 * epf_ntb_mw_bar_init() - Configure Memory window BARs585 * @ntb: NTB device that facilitates communication between HOST and VHOST586 *587 * Returns: Zero for success, or an error code in case of failure588 */589static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)590{591	int ret = 0;592	int i;593	u64 size;594	enum pci_barno barno;595	struct device *dev = &ntb->epf->dev;596 597	for (i = 0; i < ntb->num_mws; i++) {598		size = ntb->mws_size[i];599		barno = ntb->epf_ntb_bar[BAR_MW0 + i];600 601		ntb->epf->bar[barno].barno = barno;602		ntb->epf->bar[barno].size = size;603		ntb->epf->bar[barno].addr = NULL;604		ntb->epf->bar[barno].phys_addr = 0;605		ntb->epf->bar[barno].flags |= upper_32_bits(size) ?606				PCI_BASE_ADDRESS_MEM_TYPE_64 :607				PCI_BASE_ADDRESS_MEM_TYPE_32;608 609		ret = pci_epc_set_bar(ntb->epf->epc,610				      ntb->epf->func_no,611				      ntb->epf->vfunc_no,612				      &ntb->epf->bar[barno]);613		if (ret) {614			dev_err(dev, "MW set failed\n");615			goto err_alloc_mem;616		}617 618		/* Allocate EPC outbound memory windows to vpci vntb device */619		ntb->vpci_mw_addr[i] = pci_epc_mem_alloc_addr(ntb->epf->epc,620							      &ntb->vpci_mw_phy[i],621							      size);622		if (!ntb->vpci_mw_addr[i]) {623			ret = -ENOMEM;624			dev_err(dev, "Failed to allocate source address\n");625			goto err_set_bar;626		}627	}628 629	return ret;630 631err_set_bar:632	pci_epc_clear_bar(ntb->epf->epc,633			  ntb->epf->func_no,634			  ntb->epf->vfunc_no,635			  &ntb->epf->bar[barno]);636err_alloc_mem:637	epf_ntb_mw_bar_clear(ntb, i);638	return ret;639}640 641/**642 * epf_ntb_mw_bar_clear() - Clear Memory window BARs643 * @ntb: NTB device that facilitates communication between HOST and VHOST644 * @num_mws: the number of Memory window BARs that to be cleared645 */646static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb, int num_mws)647{648	enum pci_barno barno;649	int i;650 651	for (i = 0; i < num_mws; i++) {652		barno = ntb->epf_ntb_bar[BAR_MW0 + i];653		pci_epc_clear_bar(ntb->epf->epc,654				  ntb->epf->func_no,655				  ntb->epf->vfunc_no,656				  &ntb->epf->bar[barno]);657 658		pci_epc_mem_free_addr(ntb->epf->epc,659				      ntb->vpci_mw_phy[i],660				      ntb->vpci_mw_addr[i],661				      ntb->mws_size[i]);662	}663}664 665/**666 * epf_ntb_epc_destroy() - Cleanup NTB EPC interface667 * @ntb: NTB device that facilitates communication between HOST and VHOST668 *669 * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB interfaces670 */671static void epf_ntb_epc_destroy(struct epf_ntb *ntb)672{673	pci_epc_remove_epf(ntb->epf->epc, ntb->epf, 0);674	pci_epc_put(ntb->epf->epc);675}676 677/**678 * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB679 * constructs (scratchpad region, doorbell, memorywindow)680 * @ntb: NTB device that facilitates communication between HOST and VHOST681 *682 * Returns: Zero for success, or an error code in case of failure683 */684static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)685{686	const struct pci_epc_features *epc_features;687	enum pci_barno barno;688	enum epf_ntb_bar bar;689	struct device *dev;690	u32 num_mws;691	int i;692 693	barno = BAR_0;694	num_mws = ntb->num_mws;695	dev = &ntb->epf->dev;696	epc_features = pci_epc_get_features(ntb->epf->epc, ntb->epf->func_no, ntb->epf->vfunc_no);697 698	/* These are required BARs which are mandatory for NTB functionality */699	for (bar = BAR_CONFIG; bar <= BAR_MW0; bar++, barno++) {700		barno = pci_epc_get_next_free_bar(epc_features, barno);701		if (barno < 0) {702			dev_err(dev, "Fail to get NTB function BAR\n");703			return barno;704		}705		ntb->epf_ntb_bar[bar] = barno;706	}707 708	/* These are optional BARs which don't impact NTB functionality */709	for (bar = BAR_MW1, i = 1; i < num_mws; bar++, barno++, i++) {710		barno = pci_epc_get_next_free_bar(epc_features, barno);711		if (barno < 0) {712			ntb->num_mws = i;713			dev_dbg(dev, "BAR not available for > MW%d\n", i + 1);714		}715		ntb->epf_ntb_bar[bar] = barno;716	}717 718	return 0;719}720 721/**722 * epf_ntb_epc_init() - Initialize NTB interface723 * @ntb: NTB device that facilitates communication between HOST and VHOST724 *725 * Wrapper to initialize a particular EPC interface and start the workqueue726 * to check for commands from HOST. This function will write to the727 * EP controller HW for configuring it.728 *729 * Returns: Zero for success, or an error code in case of failure730 */731static int epf_ntb_epc_init(struct epf_ntb *ntb)732{733	u8 func_no, vfunc_no;734	struct pci_epc *epc;735	struct pci_epf *epf;736	struct device *dev;737	int ret;738 739	epf = ntb->epf;740	dev = &epf->dev;741	epc = epf->epc;742	func_no = ntb->epf->func_no;743	vfunc_no = ntb->epf->vfunc_no;744 745	ret = epf_ntb_config_sspad_bar_set(ntb);746	if (ret) {747		dev_err(dev, "Config/self SPAD BAR init failed");748		return ret;749	}750 751	ret = epf_ntb_configure_interrupt(ntb);752	if (ret) {753		dev_err(dev, "Interrupt configuration failed\n");754		goto err_config_interrupt;755	}756 757	ret = epf_ntb_db_bar_init(ntb);758	if (ret) {759		dev_err(dev, "DB BAR init failed\n");760		goto err_db_bar_init;761	}762 763	ret = epf_ntb_mw_bar_init(ntb);764	if (ret) {765		dev_err(dev, "MW BAR init failed\n");766		goto err_mw_bar_init;767	}768 769	if (vfunc_no <= 1) {770		ret = pci_epc_write_header(epc, func_no, vfunc_no, epf->header);771		if (ret) {772			dev_err(dev, "Configuration header write failed\n");773			goto err_write_header;774		}775	}776 777	INIT_DELAYED_WORK(&ntb->cmd_handler, epf_ntb_cmd_handler);778	queue_work(kpcintb_workqueue, &ntb->cmd_handler.work);779 780	return 0;781 782err_write_header:783	epf_ntb_mw_bar_clear(ntb, ntb->num_mws);784err_mw_bar_init:785	epf_ntb_db_bar_clear(ntb);786err_db_bar_init:787err_config_interrupt:788	epf_ntb_config_sspad_bar_clear(ntb);789 790	return ret;791}792 793 794/**795 * epf_ntb_epc_cleanup() - Cleanup all NTB interfaces796 * @ntb: NTB device that facilitates communication between HOST and VHOST797 *798 * Wrapper to cleanup all NTB interfaces.799 */800static void epf_ntb_epc_cleanup(struct epf_ntb *ntb)801{802	epf_ntb_mw_bar_clear(ntb, ntb->num_mws);803	epf_ntb_db_bar_clear(ntb);804	epf_ntb_config_sspad_bar_clear(ntb);805}806 807#define EPF_NTB_R(_name)						\808static ssize_t epf_ntb_##_name##_show(struct config_item *item,		\809				      char *page)			\810{									\811	struct config_group *group = to_config_group(item);		\812	struct epf_ntb *ntb = to_epf_ntb(group);			\813									\814	return sprintf(page, "%d\n", ntb->_name);			\815}816 817#define EPF_NTB_W(_name)						\818static ssize_t epf_ntb_##_name##_store(struct config_item *item,	\819				       const char *page, size_t len)	\820{									\821	struct config_group *group = to_config_group(item);		\822	struct epf_ntb *ntb = to_epf_ntb(group);			\823	u32 val;							\824	int ret;							\825									\826	ret = kstrtou32(page, 0, &val);					\827	if (ret)							\828		return ret;						\829									\830	ntb->_name = val;						\831									\832	return len;							\833}834 835#define EPF_NTB_MW_R(_name)						\836static ssize_t epf_ntb_##_name##_show(struct config_item *item,		\837				      char *page)			\838{									\839	struct config_group *group = to_config_group(item);		\840	struct epf_ntb *ntb = to_epf_ntb(group);			\841	struct device *dev = &ntb->epf->dev;				\842	int win_no;							\843									\844	if (sscanf(#_name, "mw%d", &win_no) != 1)			\845		return -EINVAL;						\846									\847	if (win_no <= 0 || win_no > ntb->num_mws) {			\848		dev_err(dev, "Invalid num_nws: %d value\n", ntb->num_mws); \849		return -EINVAL;						\850	}								\851									\852	return sprintf(page, "%lld\n", ntb->mws_size[win_no - 1]);	\853}854 855#define EPF_NTB_MW_W(_name)						\856static ssize_t epf_ntb_##_name##_store(struct config_item *item,	\857				       const char *page, size_t len)	\858{									\859	struct config_group *group = to_config_group(item);		\860	struct epf_ntb *ntb = to_epf_ntb(group);			\861	struct device *dev = &ntb->epf->dev;				\862	int win_no;							\863	u64 val;							\864	int ret;							\865									\866	ret = kstrtou64(page, 0, &val);					\867	if (ret)							\868		return ret;						\869									\870	if (sscanf(#_name, "mw%d", &win_no) != 1)			\871		return -EINVAL;						\872									\873	if (win_no <= 0 || win_no > ntb->num_mws) {			\874		dev_err(dev, "Invalid num_nws: %d value\n", ntb->num_mws); \875		return -EINVAL;						\876	}								\877									\878	ntb->mws_size[win_no - 1] = val;				\879									\880	return len;							\881}882 883static ssize_t epf_ntb_num_mws_store(struct config_item *item,884				     const char *page, size_t len)885{886	struct config_group *group = to_config_group(item);887	struct epf_ntb *ntb = to_epf_ntb(group);888	u32 val;889	int ret;890 891	ret = kstrtou32(page, 0, &val);892	if (ret)893		return ret;894 895	if (val > MAX_MW)896		return -EINVAL;897 898	ntb->num_mws = val;899 900	return len;901}902 903EPF_NTB_R(spad_count)904EPF_NTB_W(spad_count)905EPF_NTB_R(db_count)906EPF_NTB_W(db_count)907EPF_NTB_R(num_mws)908EPF_NTB_R(vbus_number)909EPF_NTB_W(vbus_number)910EPF_NTB_R(vntb_pid)911EPF_NTB_W(vntb_pid)912EPF_NTB_R(vntb_vid)913EPF_NTB_W(vntb_vid)914EPF_NTB_MW_R(mw1)915EPF_NTB_MW_W(mw1)916EPF_NTB_MW_R(mw2)917EPF_NTB_MW_W(mw2)918EPF_NTB_MW_R(mw3)919EPF_NTB_MW_W(mw3)920EPF_NTB_MW_R(mw4)921EPF_NTB_MW_W(mw4)922 923CONFIGFS_ATTR(epf_ntb_, spad_count);924CONFIGFS_ATTR(epf_ntb_, db_count);925CONFIGFS_ATTR(epf_ntb_, num_mws);926CONFIGFS_ATTR(epf_ntb_, mw1);927CONFIGFS_ATTR(epf_ntb_, mw2);928CONFIGFS_ATTR(epf_ntb_, mw3);929CONFIGFS_ATTR(epf_ntb_, mw4);930CONFIGFS_ATTR(epf_ntb_, vbus_number);931CONFIGFS_ATTR(epf_ntb_, vntb_pid);932CONFIGFS_ATTR(epf_ntb_, vntb_vid);933 934static struct configfs_attribute *epf_ntb_attrs[] = {935	&epf_ntb_attr_spad_count,936	&epf_ntb_attr_db_count,937	&epf_ntb_attr_num_mws,938	&epf_ntb_attr_mw1,939	&epf_ntb_attr_mw2,940	&epf_ntb_attr_mw3,941	&epf_ntb_attr_mw4,942	&epf_ntb_attr_vbus_number,943	&epf_ntb_attr_vntb_pid,944	&epf_ntb_attr_vntb_vid,945	NULL,946};947 948static const struct config_item_type ntb_group_type = {949	.ct_attrs	= epf_ntb_attrs,950	.ct_owner	= THIS_MODULE,951};952 953/**954 * epf_ntb_add_cfs() - Add configfs directory specific to NTB955 * @epf: NTB endpoint function device956 * @group: A pointer to the config_group structure referencing a group of957 *	   config_items of a specific type that belong to a specific sub-system.958 *959 * Add configfs directory specific to NTB. This directory will hold960 * NTB specific properties like db_count, spad_count, num_mws etc.,961 *962 * Returns: Pointer to config_group963 */964static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf,965					    struct config_group *group)966{967	struct epf_ntb *ntb = epf_get_drvdata(epf);968	struct config_group *ntb_group = &ntb->group;969	struct device *dev = &epf->dev;970 971	config_group_init_type_name(ntb_group, dev_name(dev), &ntb_group_type);972 973	return ntb_group;974}975 976/*==== virtual PCI bus driver, which only load virtual NTB PCI driver ====*/977 978static u32 pci_space[] = {979	0xffffffff,	/* Device ID, Vendor ID */980	0,		/* Status, Command */981	0xffffffff,	/* Base Class, Subclass, Prog Intf, Revision ID */982	0x40,		/* BIST, Header Type, Latency Timer, Cache Line Size */983	0,		/* BAR 0 */984	0,		/* BAR 1 */985	0,		/* BAR 2 */986	0,		/* BAR 3 */987	0,		/* BAR 4 */988	0,		/* BAR 5 */989	0,		/* Cardbus CIS Pointer */990	0,		/* Subsystem ID, Subsystem Vendor ID */991	0,		/* ROM Base Address */992	0,		/* Reserved, Capabilities Pointer */993	0,		/* Reserved */994	0,		/* Max_Lat, Min_Gnt, Interrupt Pin, Interrupt Line */995};996 997static int pci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val)998{999	if (devfn == 0) {1000		memcpy(val, ((u8 *)pci_space) + where, size);1001		return PCIBIOS_SUCCESSFUL;1002	}1003	return PCIBIOS_DEVICE_NOT_FOUND;1004}1005 1006static int pci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val)1007{1008	return 0;1009}1010 1011static struct pci_ops vpci_ops = {1012	.read = pci_read,1013	.write = pci_write,1014};1015 1016static int vpci_scan_bus(void *sysdata)1017{1018	struct pci_bus *vpci_bus;1019	struct epf_ntb *ndev = sysdata;1020 1021	vpci_bus = pci_scan_bus(ndev->vbus_number, &vpci_ops, sysdata);1022	if (!vpci_bus) {1023		pr_err("create pci bus failed\n");1024		return -EINVAL;1025	}1026 1027	pci_bus_add_devices(vpci_bus);1028 1029	return 0;1030}1031 1032/*==================== Virtual PCIe NTB driver ==========================*/1033 1034static int vntb_epf_mw_count(struct ntb_dev *ntb, int pidx)1035{1036	struct epf_ntb *ndev = ntb_ndev(ntb);1037 1038	return ndev->num_mws;1039}1040 1041static int vntb_epf_spad_count(struct ntb_dev *ntb)1042{1043	return ntb_ndev(ntb)->spad_count;1044}1045 1046static int vntb_epf_peer_mw_count(struct ntb_dev *ntb)1047{1048	return ntb_ndev(ntb)->num_mws;1049}1050 1051static u64 vntb_epf_db_valid_mask(struct ntb_dev *ntb)1052{1053	return BIT_ULL(ntb_ndev(ntb)->db_count) - 1;1054}1055 1056static int vntb_epf_db_set_mask(struct ntb_dev *ntb, u64 db_bits)1057{1058	return 0;1059}1060 1061static int vntb_epf_mw_set_trans(struct ntb_dev *ndev, int pidx, int idx,1062		dma_addr_t addr, resource_size_t size)1063{1064	struct epf_ntb *ntb = ntb_ndev(ndev);1065	struct pci_epf_bar *epf_bar;1066	enum pci_barno barno;1067	int ret;1068	struct device *dev;1069 1070	dev = &ntb->ntb.dev;1071	barno = ntb->epf_ntb_bar[BAR_MW0 + idx];1072	epf_bar = &ntb->epf->bar[barno];1073	epf_bar->phys_addr = addr;1074	epf_bar->barno = barno;1075	epf_bar->size = size;1076 1077	ret = pci_epc_set_bar(ntb->epf->epc, 0, 0, epf_bar);1078	if (ret) {1079		dev_err(dev, "failure set mw trans\n");1080		return ret;1081	}1082	return 0;1083}1084 1085static int vntb_epf_mw_clear_trans(struct ntb_dev *ntb, int pidx, int idx)1086{1087	return 0;1088}1089 1090static int vntb_epf_peer_mw_get_addr(struct ntb_dev *ndev, int idx,1091				phys_addr_t *base, resource_size_t *size)1092{1093 1094	struct epf_ntb *ntb = ntb_ndev(ndev);1095 1096	if (base)1097		*base = ntb->vpci_mw_phy[idx];1098 1099	if (size)1100		*size = ntb->mws_size[idx];1101 1102	return 0;1103}1104 1105static int vntb_epf_link_enable(struct ntb_dev *ntb,1106			enum ntb_speed max_speed,1107			enum ntb_width max_width)1108{1109	return 0;1110}1111 1112static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx)1113{1114	struct epf_ntb *ntb = ntb_ndev(ndev);1115	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * sizeof(u32);1116	u32 val;1117	void __iomem *base = (void __iomem *)ntb->reg;1118 1119	val = readl(base + off + ct + idx * sizeof(u32));1120	return val;1121}1122 1123static int vntb_epf_spad_write(struct ntb_dev *ndev, int idx, u32 val)1124{1125	struct epf_ntb *ntb = ntb_ndev(ndev);1126	struct epf_ntb_ctrl *ctrl = ntb->reg;1127	int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);1128	void __iomem *base = (void __iomem *)ntb->reg;1129 1130	writel(val, base + off + ct + idx * sizeof(u32));1131	return 0;1132}1133 1134static u32 vntb_epf_peer_spad_read(struct ntb_dev *ndev, int pidx, int idx)1135{1136	struct epf_ntb *ntb = ntb_ndev(ndev);1137	struct epf_ntb_ctrl *ctrl = ntb->reg;1138	int off = ctrl->spad_offset;1139	void __iomem *base = (void __iomem *)ntb->reg;1140	u32 val;1141 1142	val = readl(base + off + idx * sizeof(u32));1143	return val;1144}1145 1146static int vntb_epf_peer_spad_write(struct ntb_dev *ndev, int pidx, int idx, u32 val)1147{1148	struct epf_ntb *ntb = ntb_ndev(ndev);1149	struct epf_ntb_ctrl *ctrl = ntb->reg;1150	int off = ctrl->spad_offset;1151	void __iomem *base = (void __iomem *)ntb->reg;1152 1153	writel(val, base + off + idx * sizeof(u32));1154	return 0;1155}1156 1157static int vntb_epf_peer_db_set(struct ntb_dev *ndev, u64 db_bits)1158{1159	u32 interrupt_num = ffs(db_bits) + 1;1160	struct epf_ntb *ntb = ntb_ndev(ndev);1161	u8 func_no, vfunc_no;1162	int ret;1163 1164	func_no = ntb->epf->func_no;1165	vfunc_no = ntb->epf->vfunc_no;1166 1167	ret = pci_epc_raise_irq(ntb->epf->epc, func_no, vfunc_no,1168				PCI_IRQ_MSI, interrupt_num + 1);1169	if (ret)1170		dev_err(&ntb->ntb.dev, "Failed to raise IRQ\n");1171 1172	return ret;1173}1174 1175static u64 vntb_epf_db_read(struct ntb_dev *ndev)1176{1177	struct epf_ntb *ntb = ntb_ndev(ndev);1178 1179	return ntb->db;1180}1181 1182static int vntb_epf_mw_get_align(struct ntb_dev *ndev, int pidx, int idx,1183			resource_size_t *addr_align,1184			resource_size_t *size_align,1185			resource_size_t *size_max)1186{1187	struct epf_ntb *ntb = ntb_ndev(ndev);1188 1189	if (addr_align)1190		*addr_align = SZ_4K;1191 1192	if (size_align)1193		*size_align = 1;1194 1195	if (size_max)1196		*size_max = ntb->mws_size[idx];1197 1198	return 0;1199}1200 1201static u64 vntb_epf_link_is_up(struct ntb_dev *ndev,1202			enum ntb_speed *speed,1203			enum ntb_width *width)1204{1205	struct epf_ntb *ntb = ntb_ndev(ndev);1206 1207	return ntb->reg->link_status;1208}1209 1210static int vntb_epf_db_clear_mask(struct ntb_dev *ndev, u64 db_bits)1211{1212	return 0;1213}1214 1215static int vntb_epf_db_clear(struct ntb_dev *ndev, u64 db_bits)1216{1217	struct epf_ntb *ntb = ntb_ndev(ndev);1218 1219	ntb->db &= ~db_bits;1220	return 0;1221}1222 1223static int vntb_epf_link_disable(struct ntb_dev *ntb)1224{1225	return 0;1226}1227 1228static const struct ntb_dev_ops vntb_epf_ops = {1229	.mw_count		= vntb_epf_mw_count,1230	.spad_count		= vntb_epf_spad_count,1231	.peer_mw_count		= vntb_epf_peer_mw_count,1232	.db_valid_mask		= vntb_epf_db_valid_mask,1233	.db_set_mask		= vntb_epf_db_set_mask,1234	.mw_set_trans		= vntb_epf_mw_set_trans,1235	.mw_clear_trans		= vntb_epf_mw_clear_trans,1236	.peer_mw_get_addr	= vntb_epf_peer_mw_get_addr,1237	.link_enable		= vntb_epf_link_enable,1238	.spad_read		= vntb_epf_spad_read,1239	.spad_write		= vntb_epf_spad_write,1240	.peer_spad_read		= vntb_epf_peer_spad_read,1241	.peer_spad_write	= vntb_epf_peer_spad_write,1242	.peer_db_set		= vntb_epf_peer_db_set,1243	.db_read		= vntb_epf_db_read,1244	.mw_get_align		= vntb_epf_mw_get_align,1245	.link_is_up		= vntb_epf_link_is_up,1246	.db_clear_mask		= vntb_epf_db_clear_mask,1247	.db_clear		= vntb_epf_db_clear,1248	.link_disable		= vntb_epf_link_disable,1249};1250 1251static int pci_vntb_probe(struct pci_dev *pdev, const struct pci_device_id *id)1252{1253	int ret;1254	struct epf_ntb *ndev = (struct epf_ntb *)pdev->sysdata;1255	struct device *dev = &pdev->dev;1256 1257	ndev->ntb.pdev = pdev;1258	ndev->ntb.topo = NTB_TOPO_NONE;1259	ndev->ntb.ops =  &vntb_epf_ops;1260 1261	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));1262	if (ret) {1263		dev_err(dev, "Cannot set DMA mask\n");1264		return ret;1265	}1266 1267	ret = ntb_register_device(&ndev->ntb);1268	if (ret) {1269		dev_err(dev, "Failed to register NTB device\n");1270		return ret;1271	}1272 1273	dev_dbg(dev, "PCI Virtual NTB driver loaded\n");1274	return 0;1275}1276 1277static struct pci_device_id pci_vntb_table[] = {1278	{1279		PCI_DEVICE(0xffff, 0xffff),1280	},1281	{},1282};1283 1284static struct pci_driver vntb_pci_driver = {1285	.name           = "pci-vntb",1286	.id_table       = pci_vntb_table,1287	.probe          = pci_vntb_probe,1288};1289 1290/* ============ PCIe EPF Driver Bind ====================*/1291 1292/**1293 * epf_ntb_bind() - Initialize endpoint controller to provide NTB functionality1294 * @epf: NTB endpoint function device1295 *1296 * Initialize both the endpoint controllers associated with NTB function device.1297 * Invoked when a primary interface or secondary interface is bound to EPC1298 * device. This function will succeed only when EPC is bound to both the1299 * interfaces.1300 *1301 * Returns: Zero for success, or an error code in case of failure1302 */1303static int epf_ntb_bind(struct pci_epf *epf)1304{1305	struct epf_ntb *ntb = epf_get_drvdata(epf);1306	struct device *dev = &epf->dev;1307	int ret;1308 1309	if (!epf->epc) {1310		dev_dbg(dev, "PRIMARY EPC interface not yet bound\n");1311		return 0;1312	}1313 1314	ret = epf_ntb_init_epc_bar(ntb);1315	if (ret) {1316		dev_err(dev, "Failed to create NTB EPC\n");1317		goto err_bar_init;1318	}1319 1320	ret = epf_ntb_config_spad_bar_alloc(ntb);1321	if (ret) {1322		dev_err(dev, "Failed to allocate BAR memory\n");1323		goto err_bar_alloc;1324	}1325 1326	ret = epf_ntb_epc_init(ntb);1327	if (ret) {1328		dev_err(dev, "Failed to initialize EPC\n");1329		goto err_bar_alloc;1330	}1331 1332	epf_set_drvdata(epf, ntb);1333 1334	pci_space[0] = (ntb->vntb_pid << 16) | ntb->vntb_vid;1335	pci_vntb_table[0].vendor = ntb->vntb_vid;1336	pci_vntb_table[0].device = ntb->vntb_pid;1337 1338	ret = pci_register_driver(&vntb_pci_driver);1339	if (ret) {1340		dev_err(dev, "failure register vntb pci driver\n");1341		goto err_epc_cleanup;1342	}1343 1344	ret = vpci_scan_bus(ntb);1345	if (ret)1346		goto err_unregister;1347 1348	return 0;1349 1350err_unregister:1351	pci_unregister_driver(&vntb_pci_driver);1352err_epc_cleanup:1353	epf_ntb_epc_cleanup(ntb);1354err_bar_alloc:1355	epf_ntb_config_spad_bar_free(ntb);1356 1357err_bar_init:1358	epf_ntb_epc_destroy(ntb);1359 1360	return ret;1361}1362 1363/**1364 * epf_ntb_unbind() - Cleanup the initialization from epf_ntb_bind()1365 * @epf: NTB endpoint function device1366 *1367 * Cleanup the initialization from epf_ntb_bind()1368 */1369static void epf_ntb_unbind(struct pci_epf *epf)1370{1371	struct epf_ntb *ntb = epf_get_drvdata(epf);1372 1373	epf_ntb_epc_cleanup(ntb);1374	epf_ntb_config_spad_bar_free(ntb);1375	epf_ntb_epc_destroy(ntb);1376 1377	pci_unregister_driver(&vntb_pci_driver);1378}1379 1380// EPF driver probe1381static const struct pci_epf_ops epf_ntb_ops = {1382	.bind   = epf_ntb_bind,1383	.unbind = epf_ntb_unbind,1384	.add_cfs = epf_ntb_add_cfs,1385};1386 1387/**1388 * epf_ntb_probe() - Probe NTB function driver1389 * @epf: NTB endpoint function device1390 * @id: NTB endpoint function device ID1391 *1392 * Probe NTB function driver when endpoint function bus detects a NTB1393 * endpoint function.1394 *1395 * Returns: Zero for success, or an error code in case of failure1396 */1397static int epf_ntb_probe(struct pci_epf *epf,1398			 const struct pci_epf_device_id *id)1399{1400	struct epf_ntb *ntb;1401	struct device *dev;1402 1403	dev = &epf->dev;1404 1405	ntb = devm_kzalloc(dev, sizeof(*ntb), GFP_KERNEL);1406	if (!ntb)1407		return -ENOMEM;1408 1409	epf->header = &epf_ntb_header;1410	ntb->epf = epf;1411	ntb->vbus_number = 0xff;1412	epf_set_drvdata(epf, ntb);1413 1414	dev_info(dev, "pci-ep epf driver loaded\n");1415	return 0;1416}1417 1418static const struct pci_epf_device_id epf_ntb_ids[] = {1419	{1420		.name = "pci_epf_vntb",1421	},1422	{},1423};1424 1425static struct pci_epf_driver epf_ntb_driver = {1426	.driver.name    = "pci_epf_vntb",1427	.probe          = epf_ntb_probe,1428	.id_table       = epf_ntb_ids,1429	.ops            = &epf_ntb_ops,1430	.owner          = THIS_MODULE,1431};1432 1433static int __init epf_ntb_init(void)1434{1435	int ret;1436 1437	kpcintb_workqueue = alloc_workqueue("kpcintb", WQ_MEM_RECLAIM |1438					    WQ_HIGHPRI, 0);1439	ret = pci_epf_register_driver(&epf_ntb_driver);1440	if (ret) {1441		destroy_workqueue(kpcintb_workqueue);1442		pr_err("Failed to register pci epf ntb driver --> %d\n", ret);1443		return ret;1444	}1445 1446	return 0;1447}1448module_init(epf_ntb_init);1449 1450static void __exit epf_ntb_exit(void)1451{1452	pci_epf_unregister_driver(&epf_ntb_driver);1453	destroy_workqueue(kpcintb_workqueue);1454}1455module_exit(epf_ntb_exit);1456 1457MODULE_DESCRIPTION("PCI EPF NTB DRIVER");1458MODULE_AUTHOR("Frank Li <Frank.li@nxp.com>");1459MODULE_LICENSE("GPL v2");1460