From patchwork Thu Jun 8 14:13:02 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Pieralisi X-Patchwork-Id: 773252 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3wk6nm1XpKz9s76 for ; Fri, 9 Jun 2017 00:12:44 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751635AbdFHOMn (ORCPT ); Thu, 8 Jun 2017 10:12:43 -0400 Received: from foss.arm.com ([217.140.101.70]:49800 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751422AbdFHOMm (ORCPT ); Thu, 8 Jun 2017 10:12:42 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A8CE5164F; Thu, 8 Jun 2017 07:12:41 -0700 (PDT) Received: from red-moon.cambridge.arm.com (red-moon.cambridge.arm.com [10.1.206.55]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4A8023F3E1; Thu, 8 Jun 2017 07:12:36 -0700 (PDT) From: Lorenzo Pieralisi To: linux-pci@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, Lorenzo Pieralisi , Scott Branden , Ray Jui , Jon Mason , Arnd Bergmann , Will Deacon , Russell King , Pratyush Anand , Jingoo Han , Bjorn Helgaas , Rob Herring , Simon Horman , Mingkai Hu , Tanmay Inamdar , Murali Karicheri , Bharat Kumar Gogada , Wenrui Li , Shawn Lin , Minghuan Lian , Gabriele Paoloni , Thomas Petazzoni , Joao Pinto , Thierry Reding , Michal Simek , Stanimir Varbanov , Zhou Wang , Roy Zang , Matthew Minter , Linus Walleij Subject: [RFT PATCH v2 02/42] drivers: pci: host: iproc: Convert link check to raw PCI config accessors Date: Thu, 8 Jun 2017 15:13:02 +0100 Message-Id: <20170608141342.2018-3-lorenzo.pieralisi@arm.com> X-Mailer: git-send-email 2.10.0 In-Reply-To: <20170608141342.2018-1-lorenzo.pieralisi@arm.com> References: <20170608141342.2018-1-lorenzo.pieralisi@arm.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Current iproc driver host bridge controller driver requires struct pci_bus to be created in order to carry out PCI link checks with standard PCI config space accessors. This struct pci_bus dependency is fictitious and burdens the driver with unneeded constraints (eg to use separate APIs to create and scan the root bus). Add PCI raw config space accessors to PCIe iproc driver and remove the fictitious struct pci_bus dependency. Signed-off-by: Lorenzo Pieralisi Cc: Scott Branden Cc: Ray Jui Cc: Jon Mason --- drivers/pci/host/pcie-iproc.c | 94 ++++++++++++++++++++++++++++++++++--------- 1 file changed, 74 insertions(+), 20 deletions(-) diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c index 0f39bd2..e48b8e2 100644 --- a/drivers/pci/host/pcie-iproc.c +++ b/drivers/pci/host/pcie-iproc.c @@ -452,14 +452,13 @@ static inline void iproc_pcie_apb_err_disable(struct pci_bus *bus, * Note access to the configuration registers are protected at the higher layer * by 'pci_lock' in drivers/pci/access.c */ -static void __iomem *iproc_pcie_map_cfg_bus(struct pci_bus *bus, +static void __iomem *iproc_pcie_map_cfg_bus(struct iproc_pcie *pcie, + int busno, unsigned int devfn, int where) { - struct iproc_pcie *pcie = iproc_data(bus); unsigned slot = PCI_SLOT(devfn); unsigned fn = PCI_FUNC(devfn); - unsigned busno = bus->number; u32 val; u16 offset; @@ -499,6 +498,58 @@ static void __iomem *iproc_pcie_map_cfg_bus(struct pci_bus *bus, return (pcie->base + offset); } +static void __iomem *iproc_pcie_bus_map_cfg_bus(struct pci_bus *bus, + unsigned int devfn, + int where) +{ + return iproc_pcie_map_cfg_bus(iproc_data(bus), bus->number, devfn, + where); +} + +static int iproc_pci_raw_config_read32(struct iproc_pcie *pcie, + unsigned int devfn, int where, + int size, u32 *val) +{ + void __iomem *addr; + + addr = iproc_pcie_map_cfg_bus(pcie, 0, devfn, where & ~0x3); + if (!addr) { + *val = ~0; + return PCIBIOS_DEVICE_NOT_FOUND; + } + + *val = readl(addr); + + if (size <= 2) + *val = (*val >> (8 * (where & 3))) & ((1 << (size * 8)) - 1); + + return PCIBIOS_SUCCESSFUL; +} + +static int iproc_pci_raw_config_write32(struct iproc_pcie *pcie, + unsigned int devfn, int where, + int size, u32 val) +{ + void __iomem *addr; + u32 mask, tmp; + + addr = iproc_pcie_map_cfg_bus(pcie, 0, devfn, where & ~0x3); + if (!addr) + return PCIBIOS_DEVICE_NOT_FOUND; + + if (size == 4) { + writel(val, addr); + return PCIBIOS_SUCCESSFUL; + } + + mask = ~(((1 << (size * 8)) - 1) << ((where & 0x3) * 8)); + tmp = readl(addr) & mask; + tmp |= val << ((where & 0x3) * 8); + writel(tmp, addr); + + return PCIBIOS_SUCCESSFUL; +} + static int iproc_pcie_config_read32(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val) { @@ -524,7 +575,7 @@ static int iproc_pcie_config_write32(struct pci_bus *bus, unsigned int devfn, } static struct pci_ops iproc_pcie_ops = { - .map_bus = iproc_pcie_map_cfg_bus, + .map_bus = iproc_pcie_bus_map_cfg_bus, .read = iproc_pcie_config_read32, .write = iproc_pcie_config_write32, }; @@ -556,12 +607,11 @@ static void iproc_pcie_reset(struct iproc_pcie *pcie) msleep(100); } -static int iproc_pcie_check_link(struct iproc_pcie *pcie, struct pci_bus *bus) +static int iproc_pcie_check_link(struct iproc_pcie *pcie) { struct device *dev = pcie->dev; - u8 hdr_type; - u32 link_ctrl, class, val; - u16 pos = PCI_EXP_CAP, link_status; + u32 hdr_type, link_ctrl, link_status, class, val; + u16 pos = PCI_EXP_CAP; bool link_is_active = false; /* @@ -578,7 +628,7 @@ static int iproc_pcie_check_link(struct iproc_pcie *pcie, struct pci_bus *bus) } /* make sure we are not in EP mode */ - pci_bus_read_config_byte(bus, 0, PCI_HEADER_TYPE, &hdr_type); + iproc_pci_raw_config_read32(pcie, 0, PCI_HEADER_TYPE, 1, &hdr_type); if ((hdr_type & 0x7f) != PCI_HEADER_TYPE_BRIDGE) { dev_err(dev, "in EP mode, hdr=%#02x\n", hdr_type); return -EFAULT; @@ -588,13 +638,16 @@ static int iproc_pcie_check_link(struct iproc_pcie *pcie, struct pci_bus *bus) #define PCI_BRIDGE_CTRL_REG_OFFSET 0x43c #define PCI_CLASS_BRIDGE_MASK 0xffff00 #define PCI_CLASS_BRIDGE_SHIFT 8 - pci_bus_read_config_dword(bus, 0, PCI_BRIDGE_CTRL_REG_OFFSET, &class); + iproc_pci_raw_config_read32(pcie, 0, PCI_BRIDGE_CTRL_REG_OFFSET, + 4, &class); class &= ~PCI_CLASS_BRIDGE_MASK; class |= (PCI_CLASS_BRIDGE_PCI << PCI_CLASS_BRIDGE_SHIFT); - pci_bus_write_config_dword(bus, 0, PCI_BRIDGE_CTRL_REG_OFFSET, class); + iproc_pci_raw_config_write32(pcie, 0, PCI_BRIDGE_CTRL_REG_OFFSET, + 4, class); /* check link status to see if link is active */ - pci_bus_read_config_word(bus, 0, pos + PCI_EXP_LNKSTA, &link_status); + iproc_pci_raw_config_read32(pcie, 0, pos + PCI_EXP_LNKSTA, + 2, &link_status); if (link_status & PCI_EXP_LNKSTA_NLW) link_is_active = true; @@ -603,20 +656,21 @@ static int iproc_pcie_check_link(struct iproc_pcie *pcie, struct pci_bus *bus) #define PCI_TARGET_LINK_SPEED_MASK 0xf #define PCI_TARGET_LINK_SPEED_GEN2 0x2 #define PCI_TARGET_LINK_SPEED_GEN1 0x1 - pci_bus_read_config_dword(bus, 0, - pos + PCI_EXP_LNKCTL2, + iproc_pci_raw_config_read32(pcie, 0, + pos + PCI_EXP_LNKCTL2, 4, &link_ctrl); if ((link_ctrl & PCI_TARGET_LINK_SPEED_MASK) == PCI_TARGET_LINK_SPEED_GEN2) { link_ctrl &= ~PCI_TARGET_LINK_SPEED_MASK; link_ctrl |= PCI_TARGET_LINK_SPEED_GEN1; - pci_bus_write_config_dword(bus, 0, - pos + PCI_EXP_LNKCTL2, - link_ctrl); + iproc_pci_raw_config_write32(pcie, 0, + pos + PCI_EXP_LNKCTL2, + 4, link_ctrl); msleep(100); - pci_bus_read_config_word(bus, 0, pos + PCI_EXP_LNKSTA, - &link_status); + iproc_pci_raw_config_read32(pcie, 0, + pos + PCI_EXP_LNKSTA, + 2, &link_status); if (link_status & PCI_EXP_LNKSTA_NLW) link_is_active = true; } @@ -1260,7 +1314,7 @@ int iproc_pcie_setup(struct iproc_pcie *pcie, struct list_head *res) } pcie->root_bus = bus; - ret = iproc_pcie_check_link(pcie, bus); + ret = iproc_pcie_check_link(pcie); if (ret) { dev_err(dev, "no PCIe EP device detected\n"); goto err_rm_root_bus;