From patchwork Mon Feb 1 19:58:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kishon Vijay Abraham I X-Patchwork-Id: 12060001 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3FACFC433E6 for ; Mon, 1 Feb 2021 20:01:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 03AE864EBD for ; Mon, 1 Feb 2021 20:01:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232957AbhBAUBD (ORCPT ); Mon, 1 Feb 2021 15:01:03 -0500 Received: from fllv0015.ext.ti.com ([198.47.19.141]:39776 "EHLO fllv0015.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232807AbhBAUAh (ORCPT ); Mon, 1 Feb 2021 15:00:37 -0500 Received: from lelv0266.itg.ti.com ([10.180.67.225]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 111JxTN5037313; Mon, 1 Feb 2021 13:59:29 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1612209569; bh=iOXfY/lMDsJEK1rsY4zaxzLFqfzsHzTB4Z6DIyZi0qU=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=IYgVcJOCm8SdLJKFDrDk6CMfBnHzOjT2zFuhpD839q1MVp/3sUQneT6ijPvXUg7RR Sn1MY55E//NBnCOV8qlx+yvUltiUHr/qoT1L+wZmcKS1m6hLC/gnjT9x7/QkBaF8lV obU4nTFoFQKm48bMdRVOISSIShi1KwfFTt6AMrkM= Received: from DLEE100.ent.ti.com (dlee100.ent.ti.com [157.170.170.30]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 111JxT7S037613 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 1 Feb 2021 13:59:29 -0600 Received: from DLEE110.ent.ti.com (157.170.170.21) by DLEE100.ent.ti.com (157.170.170.30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3; Mon, 1 Feb 2021 13:59:28 -0600 Received: from fllv0039.itg.ti.com (10.64.41.19) by DLEE110.ent.ti.com (157.170.170.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3 via Frontend Transport; Mon, 1 Feb 2021 13:59:28 -0600 Received: from a0393678-ssd.dal.design.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id 111JwAQk085814; Mon, 1 Feb 2021 13:59:22 -0600 From: Kishon Vijay Abraham I To: Bjorn Helgaas , Jonathan Corbet , Kishon Vijay Abraham I , Lorenzo Pieralisi , Arnd Bergmann , Jon Mason , Dave Jiang , Allen Hubbe , Tom Joseph , Rob Herring CC: Greg Kroah-Hartman , , , , Subject: [PATCH v11 13/17] PCI: endpoint: Add EP function driver to provide NTB functionality Date: Tue, 2 Feb 2021 01:28:05 +0530 Message-ID: <20210201195809.7342-14-kishon@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210201195809.7342-1-kishon@ti.com> References: <20210201195809.7342-1-kishon@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Add a new endpoint function driver to provide NTB functionality using multiple PCIe endpoint instances. Signed-off-by: Kishon Vijay Abraham I [arnd@arndb.de: Select configfs dependency] Signed-off-by: Arnd Bergmann [yebin10@huawei.com: Fix unused but set variables] Signed-off-by: Ye Bin [geert+renesas@glider.be: Explain NTB in PCI_EPF_NTB help text] Signed-off-by: Geert Uytterhoeven --- drivers/pci/endpoint/functions/Kconfig | 13 + drivers/pci/endpoint/functions/Makefile | 1 + drivers/pci/endpoint/functions/pci-epf-ntb.c | 2128 ++++++++++++++++++ 3 files changed, 2142 insertions(+) create mode 100644 drivers/pci/endpoint/functions/pci-epf-ntb.c diff --git a/drivers/pci/endpoint/functions/Kconfig b/drivers/pci/endpoint/functions/Kconfig index 8820d0f7ec77..5f1242ca2f4e 100644 --- a/drivers/pci/endpoint/functions/Kconfig +++ b/drivers/pci/endpoint/functions/Kconfig @@ -12,3 +12,16 @@ config PCI_EPF_TEST for PCI Endpoint. If in doubt, say "N" to disable Endpoint test driver. + +config PCI_EPF_NTB + 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 PCI Endpoint. NTB driver implements NTB + controller functionality using multiple PCIe endpoint instances. + It can support NTB endpoint function devices created using + device tree. + + 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 d6fafff080e2..96ab932a537a 100644 --- a/drivers/pci/endpoint/functions/Makefile +++ b/drivers/pci/endpoint/functions/Makefile @@ -4,3 +4,4 @@ # obj-$(CONFIG_PCI_EPF_TEST) += pci-epf-test.o +obj-$(CONFIG_PCI_EPF_NTB) += pci-epf-ntb.o diff --git a/drivers/pci/endpoint/functions/pci-epf-ntb.c b/drivers/pci/endpoint/functions/pci-epf-ntb.c new file mode 100644 index 000000000000..338148cf56f5 --- /dev/null +++ b/drivers/pci/endpoint/functions/pci-epf-ntb.c @@ -0,0 +1,2128 @@ +// 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; + 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; + enum pci_epc_irq_type irq_type; + struct epf_ntb_epc *ntb_epc; + struct epf_ntb_ctrl *ctrl; + struct pci_epc *epc; + bool is_msix; + u8 func_no; + 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; + 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_EPC_IRQ_MSIX : PCI_EPC_IRQ_MSI; + ret = pci_epc_raise_irq(epc, func_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; + struct pci_epc *epc; + u64 addr, size; + int ret = 0; + u8 func_no; + + 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; + + ret = pci_epc_map_addr(epc, func_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; + struct pci_epc *epc; + u8 func_no; + + 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; + + pci_epc_unmap_addr(epc, func_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; + struct pci_epc *epc; + u8 func_no; + 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; + + ret = pci_epc_map_msi_irq(epc, func_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; + struct pci_epc *epc; + size_t align; + u64 msg_addr; + u8 func_no; + 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; + 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, 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; + struct pci_epc *epc; + u8 func_no; + + 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; + + pci_epc_unmap_addr(epc, func_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: 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 + * + * 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; + struct pci_epc *epc; + u8 func_no; + + epc = ntb_epc->epc; + func_no = ntb_epc->func_no; + barno = ntb_epc->epf_ntb_bar[BAR_PEER_SPAD]; + epf_bar = &ntb_epc->epf_bar[barno]; + pci_epc_clear_bar(epc, func_no, epf_bar); +} + +/** + * epf_ntb_peer_spad_bar_set() - Set peer scratchpad BAR + * @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 + * + * 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; + struct pci_epc *epc; + struct device *dev; + u8 func_no; + 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; + 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, 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: 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 + * + * 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; + struct pci_epc *epc; + u8 func_no; + + epc = ntb_epc->epc; + func_no = ntb_epc->func_no; + barno = ntb_epc->epf_ntb_bar[BAR_CONFIG]; + epf_bar = &ntb_epc->epf_bar[barno]; + pci_epc_clear_bar(epc, func_no, epf_bar); +} + +/** + * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR + * @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 + * + * 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; + struct epf_ntb *ntb; + struct pci_epc *epc; + struct device *dev; + u8 func_no; + int ret; + + ntb = ntb_epc->epf_ntb; + dev = &ntb->epf->dev; + + epc = ntb_epc->epc; + func_no = ntb_epc->func_no; + barno = ntb_epc->epf_ntb_bar[BAR_CONFIG]; + epf_bar = &ntb_epc->epf_bar[barno]; + + ret = pci_epc_set_bar(epc, func_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_fixed_size[barno]; + 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_fixed_size[peer_barno]; + + /* 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, align, 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; + struct pci_epc *epc; + u8 func_no; + + epc = ntb_epc->epc; + + func_no = ntb_epc->func_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, 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 capaiblity + * @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; + struct pci_epc *epc; + struct device *dev; + u32 db_count; + u8 func_no; + 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; + + 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, 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, 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 + * @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; + struct pci_epc *epc; + struct device *dev; + size_t align; + int ret, i; + u8 func_no; + 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; + 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, 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; + struct pci_epf *epf; + struct device *dev; + u8 func_no; + + dev = &ntb->epf->dev; + + ntb_epc = devm_kzalloc(dev, sizeof(*ntb_epc), GFP_KERNEL); + if (!ntb_epc) + return -ENOMEM; + + epf = ntb->epf; + 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->type = type; + ntb_epc->epf_bar = epf_bar; + ntb_epc->epf_ntb = ntb; + + epc_features = pci_epc_get_features(epc, func_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 + * @type: PRIMARY interface or SECONDARY interface + * + * 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; + struct pci_epc *epc; + struct pci_epf *epf; + struct device *dev; + u8 func_no; + int ret; + + ntb_epc = ntb->epc[type]; + epf = ntb->epf; + dev = &epf->dev; + epc = ntb_epc->epc; + func_no = ntb_epc->func_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; + } + + ret = pci_epc_write_header(epc, func_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 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_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 + * + * 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 + * + * 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; + epf_set_drvdata(epf, ntb); + + return 0; +} + +static 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");