From mboxrd@z Thu Jan 1 00:00:00 1970 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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 E7DE7C433E0 for ; Tue, 26 May 2020 09:10:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CA5A02089D for ; Tue, 26 May 2020 09:10:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731600AbgEZJKQ (ORCPT ); Tue, 26 May 2020 05:10:16 -0400 Received: from foss.arm.com ([217.140.110.172]:47912 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731548AbgEZJKP (ORCPT ); Tue, 26 May 2020 05:10:15 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id DAA331FB; Tue, 26 May 2020 02:10:14 -0700 (PDT) Received: from e121166-lin.cambridge.arm.com (e121166-lin.cambridge.arm.com [10.1.196.255]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 469253F52E; Tue, 26 May 2020 02:10:13 -0700 (PDT) Date: Tue, 26 May 2020 10:10:07 +0100 From: Lorenzo Pieralisi To: Jiaxun Yang Cc: linux-pci@vger.kernel.org, Rob Herring , Bjorn Helgaas , Rob Herring , Thomas Bogendoerfer , Huacai Chen , Paul Burton , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org Subject: Re: [PATCH v10 2/5] PCI: Add Loongson PCI Controller support Message-ID: <20200526091007.GA19547@e121166-lin.cambridge.arm.com> References: <20200427060551.1372591-1-jiaxun.yang@flygoat.com> <20200514131650.3587281-1-jiaxun.yang@flygoat.com> <20200514131650.3587281-2-jiaxun.yang@flygoat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200514131650.3587281-2-jiaxun.yang@flygoat.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Thu, May 14, 2020 at 09:16:38PM +0800, Jiaxun Yang wrote: > This controller can be found on Loongson-2K SoC, Loongson-3 > systems with RS780E/LS7A PCH. > > The RS780E part of code was previously located at > arch/mips/pci/ops-loongson3.c and now it can use generic PCI > driver implementation. > > Signed-off-by: Jiaxun Yang > Reviewed-by: Rob Herring > > -- > v2: > - Clean up according to rob's suggestions > - Claim that it can't work as a module > v3: > - Fix a typo > v4: > - More clean-ups: Drop flag check, use devfn > v7: > - Fix ordering according to huacai's suggestion > v8: > - Style clean and bugfix according to Bjorn's review > v9: > - Confirm with vendor about the details on system_bus BARs > - Further cleanups > - I think assume root_bus as 0 simplify our code a lot, as that's > always valid to the hardware, as we're not ecam or dwc, we can't > easily get host bus_nr via cfg, adding that will cause unnecessary > overhead. > > v10: > - Enhance comments about system_bus quirk and host bus quirk. > --- > drivers/pci/controller/Kconfig | 10 ++ > drivers/pci/controller/Makefile | 1 + > drivers/pci/controller/pci-loongson.c | 249 ++++++++++++++++++++++++++ > 3 files changed, 260 insertions(+) > create mode 100644 drivers/pci/controller/pci-loongson.c Acked-by: Lorenzo Pieralisi > diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig > index 91bfdb784829..ae36edb1d7db 100644 > --- a/drivers/pci/controller/Kconfig > +++ b/drivers/pci/controller/Kconfig > @@ -258,6 +258,16 @@ config PCI_HYPERV_INTERFACE > The Hyper-V PCI Interface is a helper driver allows other drivers to > have a common interface with the Hyper-V PCI frontend driver. > > +config PCI_LOONGSON > + bool "LOONGSON PCI Controller" > + depends on MACH_LOONGSON64 || COMPILE_TEST > + depends on OF > + depends on PCI_QUIRKS > + default MACH_LOONGSON64 > + help > + Say Y here if you want to enable PCI controller support on > + Loongson systems. > + > source "drivers/pci/controller/dwc/Kconfig" > source "drivers/pci/controller/mobiveil/Kconfig" > source "drivers/pci/controller/cadence/Kconfig" > diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile > index 158c59771824..fbac4b0190a0 100644 > --- a/drivers/pci/controller/Makefile > +++ b/drivers/pci/controller/Makefile > @@ -28,6 +28,7 @@ obj-$(CONFIG_PCIE_MEDIATEK) += pcie-mediatek.o > obj-$(CONFIG_PCIE_TANGO_SMP8759) += pcie-tango.o > obj-$(CONFIG_VMD) += vmd.o > obj-$(CONFIG_PCIE_BRCMSTB) += pcie-brcmstb.o > +obj-$(CONFIG_PCI_LOONGSON) += pci-loongson.o > # pcie-hisi.o quirks are needed even without CONFIG_PCIE_DW > obj-y += dwc/ > obj-y += mobiveil/ > diff --git a/drivers/pci/controller/pci-loongson.c b/drivers/pci/controller/pci-loongson.c > new file mode 100644 > index 000000000000..4879377b86f3 > --- /dev/null > +++ b/drivers/pci/controller/pci-loongson.c > @@ -0,0 +1,249 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Loongson PCI Host Controller Driver > + * > + * Copyright (C) 2020 Jiaxun Yang > + */ > + > +#include > +#include > +#include > +#include > + > +#include "../pci.h" > + > +/* Device IDs */ > +#define DEV_PCIE_PORT_0 0x7a09 > +#define DEV_PCIE_PORT_1 0x7a19 > +#define DEV_PCIE_PORT_2 0x7a29 > + > +#define DEV_LS2K_APB 0x7a02 > +#define DEV_LS7A_CONF 0x7a10 > +#define DEV_LS7A_LPC 0x7a0c > + > +#define FLAG_CFG0 BIT(0) > +#define FLAG_CFG1 BIT(1) > +#define FLAG_DEV_FIX BIT(2) > + > +struct loongson_pci { > + void __iomem *cfg0_base; > + void __iomem *cfg1_base; > + struct platform_device *pdev; > + u32 flags; > +}; > + > +/* Fixup wrong class code in PCIe bridges */ > +static void bridge_class_quirk(struct pci_dev *dev) > +{ > + dev->class = PCI_CLASS_BRIDGE_PCI << 8; > +} > +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LOONGSON, > + DEV_PCIE_PORT_0, bridge_class_quirk); > +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LOONGSON, > + DEV_PCIE_PORT_1, bridge_class_quirk); > +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LOONGSON, > + DEV_PCIE_PORT_2, bridge_class_quirk); > + > +static void system_bus_quirk(struct pci_dev *pdev) > +{ > + u16 tmp; > + > + /* > + * The address space consumed by these devices is outside the > + * resources of the host bridge. > + */ > + pdev->mmio_always_on = 1; > + pdev->non_compliant_bars = 1; > +} > +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, > + DEV_LS2K_APB, system_bus_quirk); > +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, > + DEV_LS7A_CONF, system_bus_quirk); > +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, > + DEV_LS7A_LPC, system_bus_quirk); > + > +static void loongson_mrrs_quirk(struct pci_dev *dev) > +{ > + struct pci_bus *bus = dev->bus; > + struct pci_dev *bridge; > + static const struct pci_device_id bridge_devids[] = { > + { PCI_VDEVICE(LOONGSON, DEV_PCIE_PORT_0) }, > + { PCI_VDEVICE(LOONGSON, DEV_PCIE_PORT_1) }, > + { PCI_VDEVICE(LOONGSON, DEV_PCIE_PORT_2) }, > + { 0, }, > + }; > + > + /* look for the matching bridge */ > + while (!pci_is_root_bus(bus)) { > + bridge = bus->self; > + bus = bus->parent; > + /* > + * Some Loongson PCIe ports have a h/w limitation of > + * 256 bytes maximum read request size. They can't handle > + * anything larger than this. So force this limit on > + * any devices attached under these ports. > + */ > + if (pci_match_id(bridge_devids, bridge)) { > + if (pcie_get_readrq(dev) > 256) { > + pci_info(dev, "limiting MRRS to 256\n"); > + pcie_set_readrq(dev, 256); > + } > + break; > + } > + } > +} > +DECLARE_PCI_FIXUP_ENABLE(PCI_ANY_ID, PCI_ANY_ID, loongson_mrrs_quirk); > + > +static void __iomem *cfg1_map(struct loongson_pci *priv, int bus, > + unsigned int devfn, int where) > +{ > + unsigned long addroff = 0x0; > + > + if (bus != 0) > + addroff |= BIT(28); /* Type 1 Access */ > + addroff |= (where & 0xff) | ((where & 0xf00) << 16); > + addroff |= (bus << 16) | (devfn << 8); > + return priv->cfg1_base + addroff; > +} > + > +static void __iomem *cfg0_map(struct loongson_pci *priv, int bus, > + unsigned int devfn, int where) > +{ > + unsigned long addroff = 0x0; > + > + if (bus != 0) > + addroff |= BIT(24); /* Type 1 Access */ > + addroff |= (bus << 16) | (devfn << 8) | where; > + return priv->cfg0_base + addroff; > +} > + > +void __iomem *pci_loongson_map_bus(struct pci_bus *bus, unsigned int devfn, > + int where) > +{ > + unsigned char busnum = bus->number; > + struct pci_host_bridge *bridge = pci_find_host_bridge(bus); > + struct loongson_pci *priv = pci_host_bridge_priv(bridge); > + > + /* > + * Do not read more than one device on the bus other than > + * the host bus. For our hardware the root bus is always bus 0. > + */ > + if (priv->flags & FLAG_DEV_FIX && busnum != 0 && > + PCI_SLOT(devfn) > 0) > + return NULL; > + > + /* CFG0 can only access standard space */ > + if (where < PCI_CFG_SPACE_SIZE && priv->cfg0_base) > + return cfg0_map(priv, busnum, devfn, where); > + > + /* CFG1 can access extended space */ > + if (where < PCI_CFG_SPACE_EXP_SIZE && priv->cfg1_base) > + return cfg1_map(priv, busnum, devfn, where); > + > + return NULL; > +} > + > +static int loongson_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) > +{ > + int irq; > + u8 val; > + > + irq = of_irq_parse_and_map_pci(dev, slot, pin); > + if (irq > 0) > + return irq; > + > + /* Care i8259 legacy systems */ > + pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &val); > + /* i8259 only have 15 IRQs */ > + if (val > 15) > + return 0; > + > + return val; > +} > + > +/* H/w only accept 32-bit PCI operations */ > +static struct pci_ops loongson_pci_ops = { > + .map_bus = pci_loongson_map_bus, > + .read = pci_generic_config_read32, > + .write = pci_generic_config_write32, > +}; > + > +static const struct of_device_id loongson_pci_of_match[] = { > + { .compatible = "loongson,ls2k-pci", > + .data = (void *)(FLAG_CFG0 | FLAG_CFG1 | FLAG_DEV_FIX), }, > + { .compatible = "loongson,ls7a-pci", > + .data = (void *)(FLAG_CFG0 | FLAG_CFG1 | FLAG_DEV_FIX), }, > + { .compatible = "loongson,rs780e-pci", > + .data = (void *)(FLAG_CFG0), }, > + {} > +}; > + > +static int loongson_pci_probe(struct platform_device *pdev) > +{ > + struct loongson_pci *priv; > + struct device *dev = &pdev->dev; > + struct device_node *node = dev->of_node; > + struct pci_host_bridge *bridge; > + struct resource *regs; > + int err; > + > + if (!node) > + return -ENODEV; > + > + bridge = devm_pci_alloc_host_bridge(dev, sizeof(*priv)); > + if (!bridge) > + return -ENODEV; > + > + priv = pci_host_bridge_priv(bridge); > + priv->pdev = pdev; > + priv->flags = (unsigned long)of_device_get_match_data(dev); > + > + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + if (!regs) { > + dev_err(dev, "missing mem resources for cfg0\n"); > + return -EINVAL; > + } > + > + priv->cfg0_base = devm_pci_remap_cfg_resource(dev, regs); > + if (IS_ERR(priv->cfg0_base)) > + return PTR_ERR(priv->cfg0_base); > + > + /* CFG1 is optional */ > + if (priv->flags & FLAG_CFG1) { > + regs = platform_get_resource(pdev, IORESOURCE_MEM, 1); > + if (!regs) > + dev_info(dev, "missing mem resource for cfg1\n"); > + else { > + priv->cfg1_base = devm_pci_remap_cfg_resource(dev, regs); > + if (IS_ERR(priv->cfg1_base)) > + priv->cfg1_base = NULL; > + } > + } > + > + err = pci_parse_request_of_pci_ranges(dev, &bridge->windows, > + &bridge->dma_ranges, NULL); > + if (err) { > + dev_err(dev, "failed to get bridge resources\n"); > + return err; > + } > + > + bridge->dev.parent = dev; > + bridge->sysdata = priv; > + bridge->ops = &loongson_pci_ops; > + bridge->map_irq = loongson_map_irq; > + > + err = pci_host_probe(bridge); > + if (err) > + return err; > + > + return 0; > +} > + > +static struct platform_driver loongson_pci_driver = { > + .driver = { > + .name = "loongson-pci", > + .of_match_table = loongson_pci_of_match, > + }, > + .probe = loongson_pci_probe, > +}; > +builtin_platform_driver(loongson_pci_driver); > -- > 2.26.2 >