Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933665AbaGPRid (ORCPT ); Wed, 16 Jul 2014 13:38:33 -0400 Received: from mail-ig0-f172.google.com ([209.85.213.172]:37032 "EHLO mail-ig0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754547AbaGPRi3 (ORCPT ); Wed, 16 Jul 2014 13:38:29 -0400 Date: Wed, 16 Jul 2014 11:38:24 -0600 From: Bjorn Helgaas To: Srikanth Thokala Cc: michal.simek@xilinx.com, grant.likely@linaro.org, robh+dt@kernel.org, arnd@arndb.de, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Subject: Re: [PATCH v4] pcie: Add Xilinx PCIe Host Bridge IP driver Message-ID: <20140716173824.GA24357@google.com> References: <1404361654-2894-1-git-send-email-sthokal@xilinx.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1404361654-2894-1-git-send-email-sthokal@xilinx.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 03, 2014 at 09:57:34AM +0530, Srikanth Thokala wrote: > This is the driver for Xilinx AXI PCIe Host Bridge Soft IP > > Signed-off-by: Srikanth Thokala > --- > Changes in v4: > - Regarding the comments to separate ECAM functionality, > I have sent a separate patch and it is decided to implement > it later. The patch is here, > https://lkml.org/lkml/2014/5/18/54 > - Fixed issue with adding configuration bus resource. > - Moved the logic for setting up bus resources to probe() from > pcie_setup(). > - Instead of mapping all the MSI interrupts in the probe, changed > to map only when a MSI is requested. > - Earlier, the implementation of legacy and MSI interrupts init- > is mutually exclusive, now changed to have the legacy interrupts > init always and MSI interrupt init based on CONFIG_PCI_MSI flag. > - Regarding the MSI generic implementation comment, I will plan to > do on top of this driver patch. > - Rebased on 3.16-rc2. > - Fixed other minor comments. > - Thanks Arnd and Bjorn for the review. > > Changes in v3: > - Rebased on v3.15.0-rc1 > - Added support for interrupt-map DT functionality. > - Removed map_irq() wrapper, instead using of_irq_parse_and_map_pci(). > - Modified resource mapping logic as per the series > "PCI: ARM: add support for generic PCI host controller" > - Modified devicetree binding documentation to update with interrupt- > map properties. > - Use devm calls wherever applicable. > - Fixed minor comments from Jason > - Thanks Jason for the review and suggestions. > > Changes in v2: > - Rebased on v3.14.0-rc8 > - Removed IP specific DT properties like include-rc, axibar-num etc., > as suggested by Jason and Bjorn, Thanks > --- > .../devicetree/bindings/pci/xilinx-pcie.txt | 62 ++ > drivers/pci/host/Kconfig | 7 + > drivers/pci/host/Makefile | 1 + > drivers/pci/host/pci-xilinx.c | 1027 ++++++++++++++++++++ > 4 files changed, 1097 insertions(+) > create mode 100644 Documentation/devicetree/bindings/pci/xilinx-pcie.txt > create mode 100644 drivers/pci/host/pci-xilinx.c I see I forgot to ask for a MAINTAINERS entry for this driver. Can you add one? I'd also like an ack from Arnd or another devicetree person for the binding. I have a few minor comments below. > diff --git a/Documentation/devicetree/bindings/pci/xilinx-pcie.txt b/Documentation/devicetree/bindings/pci/xilinx-pcie.txt > new file mode 100644 > index 0000000..3e2c88d > --- /dev/null > +++ b/Documentation/devicetree/bindings/pci/xilinx-pcie.txt > @@ -0,0 +1,62 @@ > +* Xilinx AXI PCIe Root Port Bridge DT description > + > +Required properties: > +- #address-cells: Address representation for root ports, set to <3> > +- #size-cells: Size representation for root ports, set to <2> > +- #interrupt-cells: specifies the number of cells needed to encode an > + interrupt source. The value must be 1. > +- compatible: Should contain "xlnx,axi-pcie-host-1.00.a" > +- reg: Should contain AXI PCIe registers location and length > +- device_type: must be "pci" > +- interrupts: Should contain AXI PCIe interrupt > +- interrupt-map-mask, > + interrupt-map: standard PCI properties to define the mapping of the > + PCI interface to interrupt numbers. > +- ranges: ranges for the PCI memory regions (I/O space region is not > + supported by hardware) > + Please refer to the standard PCI bus binding document for a more > + detailed explanation > + > +Optional properties: > +- bus-range: PCI bus numbers covered > + > +Interrupt controller child node > ++++++++++++++++++++++++++++++++ > +Required properties: > +- interrupt-controller: identifies the node as an interrupt controller > +- #address-cells: specifies the number of cells needed to encode an > + address. The value must be 0. > +- #interrupt-cells: specifies the number of cells needed to encode an > + interrupt source. The value must be 1. > + > +NOTE: > +The core provides a single interrupt for both INTx/MSI messages. So, > +created a interrupt controller node to support 'interrupt-map' DT > +functionality. The driver will create an IRQ domain for this map, decode > +the four INTx interrupts in ISR and route them to this domain. > + > + > +Example: > +++++++++ > + > + pci_express: axi-pcie@50000000 { > + #address-cells = <3>; > + #size-cells = <2>; > + #interrupt-cells = <1>; > + compatible = "xlnx,axi-pcie-host-1.00.a"; > + reg = < 0x50000000 0x10000000 >; > + device_type = "pci"; > + interrupts = < 0 52 4 >; > + interrupt-map-mask = <0 0 0 7>; > + interrupt-map = <0 0 0 1 &pcie_intc 1>, > + <0 0 0 2 &pcie_intc 2>, > + <0 0 0 3 &pcie_intc 3>, > + <0 0 0 4 &pcie_intc 4>; > + ranges = < 0x02000000 0 0x60000000 0x60000000 0 0x10000000 >; > + > + pcie_intc: interrupt-controller { > + interrupt-controller; > + #address-cells = <0>; > + #interrupt-cells = <1>; > + } > + }; > diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig > index 21df477..afedcde 100644 > --- a/drivers/pci/host/Kconfig > +++ b/drivers/pci/host/Kconfig > @@ -46,4 +46,11 @@ config PCI_HOST_GENERIC > Say Y here if you want to support a simple generic PCI host > controller, such as the one emulated by kvmtool. > > +config PCI_XILINX > + bool "Xilinx AXI PCIe host bridge support" > + depends on ARCH_ZYNQ > + help > + Say 'Y' here if you want kernel to support the Xilinx AXI PCIe > + Host Bridge driver. > + > endmenu > diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile > index 611ba4b..68dfd06 100644 > --- a/drivers/pci/host/Makefile > +++ b/drivers/pci/host/Makefile > @@ -6,3 +6,4 @@ obj-$(CONFIG_PCI_TEGRA) += pci-tegra.o > obj-$(CONFIG_PCI_RCAR_GEN2) += pci-rcar-gen2.o > obj-$(CONFIG_PCI_RCAR_GEN2_PCIE) += pcie-rcar.o > obj-$(CONFIG_PCI_HOST_GENERIC) += pci-host-generic.o > +obj-$(CONFIG_PCI_XILINX) += pci-xilinx.o > diff --git a/drivers/pci/host/pci-xilinx.c b/drivers/pci/host/pci-xilinx.c > new file mode 100644 > index 0000000..57d59e7 > --- /dev/null > +++ b/drivers/pci/host/pci-xilinx.c > @@ -0,0 +1,1027 @@ > +/* > + * PCIe host controller driver for Xilinx AXI PCIe Bridge > + * > + * Copyright (c) 2012 - 2014 Xilinx, Inc. > + * > + * Based on the Tegra PCIe driver > + * > + * Bits taken from Synopsys Designware Host controller driver and > + * ARM PCI Host generic driver. > + * > + * This program is free software: you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation, either version 2 of the License, or > + * (at your option) any later version. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* Register definitions */ > +#define XILINX_PCIE_REG_VSECC 0x00000128 > +#define XILINX_PCIE_REG_VSECH 0x0000012c > +#define XILINX_PCIE_REG_BIR 0x00000130 > +#define XILINX_PCIE_REG_BSCR 0x00000134 > +#define XILINX_PCIE_REG_IDR 0x00000138 > +#define XILINX_PCIE_REG_IMR 0x0000013c > +#define XILINX_PCIE_REG_BLR 0x00000140 > +#define XILINX_PCIE_REG_PSCR 0x00000144 > +#define XILINX_PCIE_REG_RPSC 0x00000148 > +#define XILINX_PCIE_REG_MSIBASE1 0x0000014c > +#define XILINX_PCIE_REG_MSIBASE2 0x00000150 > +#define XILINX_PCIE_REG_RPEFR 0x00000154 > +#define XILINX_PCIE_REG_RPIFR1 0x00000158 > +#define XILINX_PCIE_REG_RPIFR2 0x0000015c > +#define XILINX_PCIE_REG_VSECC2 0x00000200 > +#define XILINX_PCIE_REG_VSECH2 0x00000204 > + > +/* Interrupt registers definitions */ > +#define XILINX_PCIE_INTR_LINK_DOWN BIT(0) > +#define XILINX_PCIE_INTR_ECRC_ERR BIT(1) > +#define XILINX_PCIE_INTR_STR_ERR BIT(2) > +#define XILINX_PCIE_INTR_HOT_RESET BIT(3) > +#define XILINX_PCIE_INTR_CFG_COMPL GENMASK(7, 5) > +#define XILINX_PCIE_INTR_CFG_TIMEOUT BIT(8) > +#define XILINX_PCIE_INTR_CORRECTABLE BIT(9) > +#define XILINX_PCIE_INTR_NONFATAL BIT(10) > +#define XILINX_PCIE_INTR_FATAL BIT(11) > +#define XILINX_PCIE_INTR_INTX BIT(16) > +#define XILINX_PCIE_INTR_MSI BIT(17) > +#define XILINX_PCIE_INTR_SLV_UNSUPP BIT(20) > +#define XILINX_PCIE_INTR_SLV_UNEXP BIT(21) > +#define XILINX_PCIE_INTR_SLV_COMPL BIT(22) > +#define XILINX_PCIE_INTR_SLV_ERRP BIT(23) > +#define XILINX_PCIE_INTR_SLV_CMPABT BIT(24) > +#define XILINX_PCIE_INTR_SLV_ILLBUR BIT(25) > +#define XILINX_PCIE_INTR_MST_DECERR BIT(26) > +#define XILINX_PCIE_INTR_MST_SLVERR BIT(27) > +#define XILINX_PCIE_INTR_MST_ERRP BIT(28) > +#define XILINX_PCIE_IMR_ALL_MASK 0x1FF30FED > +#define XILINX_PCIE_IDR_ALL_MASK 0xFFFFFFFF > + > +/* Root Port Error FIFO Read Register definitions */ > +#define XILINX_PCIE_RPEFR_ERR_VALID BIT(18) > +#define XILINX_PCIE_RPEFR_REQ_ID GENMASK(15, 0) > +#define XILINX_PCIE_RPEFR_ALL_MASK 0xFFFFFFFF > + > +/* Root Port Interrupt FIFO Read Register 1 definitions */ > +#define XILINX_PCIE_RPIFR1_INTR_VALID BIT(31) > +#define XILINX_PCIE_RPIFR1_MSI_INTR BIT(30) > +#define XILINX_PCIE_RPIFR1_INTR_ASSRT BIT(29) > +#define XILINX_PCIE_RPIFR1_INTR_MASK GENMASK(28, 27) > +#define XILINX_PCIE_RPIFR1_MSI_ADR_MASK GENMASK(26, 16) > +#define XILINX_PCIE_RPIFR1_ALL_MASK 0xFFFFFFFF > +#define XILINX_PCIE_RPIFR1_INTR_SHIFT 27 > +#define XILINX_PCIE_RPIFR1_MSI_ADR_SHIFT 16 > + > +/* Bridge Info Register definitions */ > +#define XILINX_PCIE_BIR_ECAM_SZ_MASK GENMASK(18, 16) > +#define XILINX_PCIE_BIR_ECAM_SZ_SHIFT 16 > + > +/* Root Port Interrupt FIFO Read Register 2 definitions */ > +#define XILINX_PCIE_RPIFR2_MSG_DATA GENMASK(15, 0) > + > +/* Root Port Status/control Register definitions */ > +#define XILINX_PCIE_REG_RPSC_BEN BIT(0) > + > +/* Phy Status/Control Register definitions */ > +#define XILINX_PCIE_REG_PSCR_LNKUP BIT(11) > + > +/* ECAM definitions */ > +#define ECAM_BUS_NUM_SHIFT 20 > +#define ECAM_DEV_NUM_SHIFT 12 > + > +/* PCI Configuration space Bus Number Register definitions */ > +#define PCI_SECONDARY_BUS_NUM_SHIFT 8 > +#define PCI_SUBORDINATE_BUS_NUM_SHIFT 16 > +#define PCI_LATENCY_TIMER_MASK GENMASK(31, 24) These three #defines aren't used; can you remove them? (If you need them someday, you should either try to use generic definitions from include/uapi/linux/pci_regs.h, or if they're Xilinx-specific, rename them so they look Xilinx-specific rather than generic. > + > +/* Number of MSI IRQs */ > +#define XILINX_NUM_MSI_IRQS 128 > + > +/* Number of Memory Resources */ > +#define XILINX_MAX_NUM_RESOURCES 3 > + > +/** > + * struct xilinx_pcie_port - PCIe port information > + * @reg_base: IO Mapped Register Base > + * @irq: Interrupt number > + * @msi_pages: MSI pages > + * @root_busno: Root Bus number > + * @link_up: Link status flag > + * @dev: Device pointer > + * @irq_domain: IRQ domain pointer > + * @bus_range: Bus range > + * @resources: Bus Resources > + */ > +struct xilinx_pcie_port { > + void __iomem *reg_base; > + u32 irq; > + unsigned long msi_pages; > + u8 root_busno; > + bool link_up; > + struct device *dev; > + struct irq_domain *irq_domain; > + struct resource bus_range; > + struct list_head resources; > +}; > + > +static DECLARE_BITMAP(msi_irq_in_use, XILINX_NUM_MSI_IRQS); > + > +static inline struct xilinx_pcie_port *sys_to_pcie(struct pci_sys_data *sys) > +{ > + return sys->private_data; > +} > + > +static inline u32 pcie_read(struct xilinx_pcie_port *port, u32 reg) > +{ > + return readl(port->reg_base + reg); > +} > + > +static inline void pcie_write(struct xilinx_pcie_port *port, > + u32 val, u32 reg) > +{ > + writel(val, port->reg_base + reg); > +} > + > +static inline bool xilinx_pcie_is_link_up(struct xilinx_pcie_port *port) Bool function names should be statements or properties, not questions, since a statement can be true or false but a question cannot. For example, in this case, "xilinx_pcie_link_up()" or "xilinx_pcie_link_is_up()" would read better. > +{ > + return (pcie_read(port, XILINX_PCIE_REG_PSCR) & > + XILINX_PCIE_REG_PSCR_LNKUP) ? 1 : 0; > +} > + > +/** > + * xilinx_pcie_clear_err_interrupts - Clear Error Interrupts > + * @port: PCIe port information > + */ > +static inline void > +xilinx_pcie_clear_err_interrupts(struct xilinx_pcie_port *port) Put the signature all on one line. It probably doesn't need to be inline (we're making a couple register accesses, so speed isn't a concern), and removing that will make it fit. > +{ > + u32 val = pcie_read(port, XILINX_PCIE_REG_RPEFR); > + > + if (val & XILINX_PCIE_RPEFR_ERR_VALID) { > + dev_dbg(port->dev, "Requester ID %d\n", > + val & XILINX_PCIE_RPEFR_REQ_ID); > + pcie_write(port, XILINX_PCIE_RPEFR_ALL_MASK, > + XILINX_PCIE_REG_RPEFR); > + } > +} > + > +/** > + * xilinx_pcie_verify_config - Verify configuration > + * @bus: PCI Bus structure > + * @devfn: device/function > + * > + * Return: 0 on success and error value for invalid configuration > + */ > +static int xilinx_pcie_verify_config(struct pci_bus *bus, > + unsigned int devfn) "verify_config" is not a great function name because it doesn't give a good clue about what the return value is. If you make it boolean and name it, e.g., xilinx_pcie_valid_device(), then it's obvious. > +{ > + struct xilinx_pcie_port *port = sys_to_pcie(bus->sysdata); > + > + /* Check if link is up when trying to access downstream ports */ > + if (bus->number != port->root_busno) > + if (!xilinx_pcie_is_link_up(port)) > + return -EINVAL; > + > + /* Only one device down on each root port */ > + if (bus->number == port->root_busno && devfn > 0) > + return -EINVAL; > + > + /* > + * Do not read more than one device on the bus directly attached > + * to RC. > + */ > + if (bus->primary == port->root_busno && devfn > 0) > + return -EINVAL; > + > + return 0; > +} > + > +/** > + * xilinx_pcie_get_config_base - Get configuration base > + * @bus: PCI Bus structure > + * @devfn: Device/function > + * @where: Offset from base > + * > + * Return: Base address of the configuration space needed to be > + * accessed. > + */ > +static void __iomem *xilinx_pcie_get_config_base(struct pci_bus *bus, > + unsigned int devfn, > + int where) "xilinx_pcie_config_base()" would be sufficient. We use "get" as a clue that we're acquiring a reference (obviously not an issue here, but I think the "get" in this function name is still a bit redundant.) > +{ > + struct xilinx_pcie_port *port = sys_to_pcie(bus->sysdata); > + int relbus; > + > + relbus = (bus->number << ECAM_BUS_NUM_SHIFT) | > + (devfn << ECAM_DEV_NUM_SHIFT); > + > + return port->reg_base + relbus + where; > +} > + > +/** > + * xilinx_pcie_read_config - Read configuration space > + * @bus: PCI Bus structure > + * @devfn: Device/function > + * @where: Offset from base > + * @size: Byte/word/dword > + * @val: Value to be read > + * > + * Return: PCIBIOS_SUCCESSFUL on success > + * EINVAL/PCIBIOS_DEVICE_NOT_FOUND/PCIBIOS_BAD_REGISTER_NUMBER > + * on failure. > + */ > +static int xilinx_pcie_read_config(struct pci_bus *bus, > + unsigned int devfn, int where, > + int size, u32 *val) > +{ > + struct xilinx_pcie_port *port = sys_to_pcie(bus->sysdata); > + void __iomem *addr; > + > + if (!port) { > + BUG(); > + return -EINVAL; > + } I don't think you need to test "port" for NULL here. And I don't think callers will be prepared for -EINVAL anyway; they'll be expecting PCIBIOS_* values. > + if (xilinx_pcie_verify_config(bus, devfn)) { > + *val = 0xFFFFFFFF; > + return PCIBIOS_DEVICE_NOT_FOUND; > + } > + > + addr = xilinx_pcie_get_config_base(bus, devfn, where); > + > + switch (size) { > + case 1: > + *val = readb(addr); > + break; > + case 2: > + *val = readw(addr); > + break; > + default: > + *val = readl(addr); > + break; > + } > + > + return PCIBIOS_SUCCESSFUL; > +} > + > +/** > + * xilinx_pcie_write_config - Write configuration space > + * @bus: PCI Bus structure > + * @devfn: Device/function > + * @where: Offset from base > + * @size: Byte/word/dword > + * @val: Value to be written to device > + * > + * Return: PCIBIOS_SUCCESSFUL on success, > + * EINVAL/PCIBIOS_DEVICE_NOT_FOUND/PCIBIOS_BAD_REGISTER_NUMBER > + * on failure. > + */ > +static int xilinx_pcie_write_config(struct pci_bus *bus, > + unsigned int devfn, int where, > + int size, u32 val) > +{ > + struct xilinx_pcie_port *port = sys_to_pcie(bus->sysdata); > + void __iomem *addr; > + > + if (!port) { > + BUG(); > + return -EINVAL; > + } I don't think this test is necessary. > + if (xilinx_pcie_verify_config(bus, devfn)) > + return PCIBIOS_DEVICE_NOT_FOUND; > + > + addr = xilinx_pcie_get_config_base(bus, devfn, where); > + > + switch (size) { > + case 1: > + writeb(val, addr); > + break; > + case 2: > + writew(val, addr); > + break; > + default: > + writel(val, addr); > + break; > + } > + > + return PCIBIOS_SUCCESSFUL; > +} > + > +/* PCIe operations */ > +static struct pci_ops xilinx_pcie_ops = { > + .read = xilinx_pcie_read_config, > + .write = xilinx_pcie_write_config, > +}; > + > +/* MSI functions */ > + > +/** > + * xilinx_pcie_destroy_msi - Free MSI number > + * @irq: IRQ to be freed > + */ > +static void xilinx_pcie_destroy_msi(unsigned int irq) > +{ > + struct irq_desc *desc; > + struct msi_desc *msi; > + struct xilinx_pcie_port *port; > + > + desc = irq_to_desc(irq); > + msi = irq_desc_get_msi_desc(desc); > + port = sys_to_pcie(msi->dev->bus->sysdata); > + if (!port) { > + BUG(); > + return; > + } Or this one. > + if (!test_bit(irq, msi_irq_in_use)) > + dev_err(port->dev, "Trying to free unused MSI#%d\n", irq); > + else > + clear_bit(irq, msi_irq_in_use); > +} > + > +/** > + * xilinx_pcie_assign_msi - Allocate MSI number > + * @port: PCIe port structure > + * > + * Return: A valid IRQ on success and error value on failure. > + */ > +static int xilinx_pcie_assign_msi(struct xilinx_pcie_port *port) > +{ > + int pos; > + > + pos = find_first_zero_bit(msi_irq_in_use, XILINX_NUM_MSI_IRQS); > + if (pos < XILINX_NUM_MSI_IRQS) > + set_bit(pos, msi_irq_in_use); > + else > + return -ENOSPC; > + > + return pos; > +} > + > +/** > + * xilinx_msi_teardown_irq - Destroy the MSI > + * @chip: MSI Chip descriptor > + * @irq: MSI IRQ to destroy > + */ > +static void xilinx_msi_teardown_irq(struct msi_chip *chip, unsigned int irq) > +{ > + xilinx_pcie_destroy_msi(irq); > +} > + > +/** > + * xilinx_pcie_msi_setup_irq - Setup MSI request > + * @chip: MSI chip pointer > + * @pdev: PCIe device pointer > + * @desc: MSI descriptor pointer > + * > + * Return: '0' on success and error value on failure > + */ > +static int xilinx_pcie_msi_setup_irq(struct msi_chip *chip, > + struct pci_dev *pdev, > + struct msi_desc *desc) > +{ > + struct xilinx_pcie_port *port = sys_to_pcie(pdev->bus->sysdata); > + unsigned int irq; > + int hwirq; > + struct msi_msg msg; > + phys_addr_t msg_addr; > + > + if (!port) { > + BUG(); > + return -EINVAL; > + } Or this one. > + hwirq = xilinx_pcie_assign_msi(port); > + if (irq < 0) > + return irq; > + > + irq = irq_create_mapping(port->irq_domain, hwirq); > + if (!irq) > + return -EINVAL; > + > + irq_set_msi_desc(irq, desc); > + > + msg_addr = virt_to_phys((void *)port->msi_pages); > + > + msg.address_hi = 0; > + msg.address_lo = msg_addr; > + msg.data = irq; > + > + write_msi_msg(irq, &msg); > + > + return 0; > +} > + > +/* MSI Chip Descriptor */ > +static struct msi_chip xilinx_pcie_msi_chip = { > + .setup_irq = xilinx_pcie_msi_setup_irq, > + .teardown_irq = xilinx_msi_teardown_irq, > +}; > + > +/* HW Interrupt Chip Descriptor */ > +static struct irq_chip xilinx_msi_irq_chip = { > + .name = "Xilinx PCIe MSI", > + .irq_enable = unmask_msi_irq, > + .irq_disable = mask_msi_irq, > + .irq_mask = mask_msi_irq, > + .irq_unmask = unmask_msi_irq, > +}; > + > +/** > + * xilinx_pcie_msi_map - Set the handler for the MSI and mark IRQ as valid > + * @domain: IRQ domain > + * @irq: Virtual IRQ number > + * @hwirq: HW interrupt number > + * > + * Return: Always returns 0. > + */ > +static int xilinx_pcie_msi_map(struct irq_domain *domain, unsigned int irq, > + irq_hw_number_t hwirq) > +{ > + irq_set_chip_and_handler(irq, &xilinx_msi_irq_chip, handle_simple_irq); > + irq_set_chip_data(irq, domain->host_data); > + set_irq_flags(irq, IRQF_VALID); > + > + return 0; > +} > + > +/* IRQ Domain operations */ > +static const struct irq_domain_ops msi_domain_ops = { > + .map = xilinx_pcie_msi_map, > +}; > + > +/** > + * xilinx_pcie_enable_msi - Enable MSI support > + * @port: PCIe port information > + */ > +static void xilinx_pcie_enable_msi(struct xilinx_pcie_port *port) > +{ > + phys_addr_t msg_addr; > + > + port->msi_pages = __get_free_pages(GFP_KERNEL, 0); > + msg_addr = virt_to_phys((void *)port->msi_pages); > + pcie_write(port, 0x0, XILINX_PCIE_REG_MSIBASE1); > + pcie_write(port, msg_addr, XILINX_PCIE_REG_MSIBASE2); > +} > + > +/** > + * xilinx_pcie_add_bus - Add MSI chip info to PCIe bus > + * @bus: PCIe bus > + */ > +static void xilinx_pcie_add_bus(struct pci_bus *bus) > +{ > + if (IS_ENABLED(CONFIG_PCI_MSI)) { Did you verify that this builds with both CONFIG_PCI_MSI=y and with it unset? > + struct xilinx_pcie_port *port = sys_to_pcie(bus->sysdata); > + > + if (!port) > + return; Unnecessary "port" test. > + xilinx_pcie_msi_chip.dev = port->dev; > + bus->msi = &xilinx_pcie_msi_chip; > + } > +} > + > +/* INTx Functions */ > + > +/** > + * xilinx_pcie_intx_map - Set the handler for the INTx and mark IRQ as valid > + * @domain: IRQ domain > + * @irq: Virtual IRQ number > + * @hwirq: HW interrupt number > + * > + * Return: Always returns 0. > + */ > +static int xilinx_pcie_intx_map(struct irq_domain *domain, unsigned int irq, > + irq_hw_number_t hwirq) > +{ > + irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq); > + irq_set_chip_data(irq, domain->host_data); > + set_irq_flags(irq, IRQF_VALID); > + > + return 0; > +} > + > +/* INTx IRQ Domain operations */ > +static const struct irq_domain_ops intx_domain_ops = { > + .map = xilinx_pcie_intx_map, > +}; > + > +/* PCIe HW Functions */ > + > +/** > + * xilinx_pcie_intr_handler - Interrupt Service Handler > + * @irq: IRQ number > + * @data: PCIe port information > + * > + * Return: IRQ_HANDLED on success and IRQ_NONE on failure > + */ > +static irqreturn_t xilinx_pcie_intr_handler(int irq, void *data) > +{ > + struct xilinx_pcie_port *port = (struct xilinx_pcie_port *)data; > + u32 val, mask, status, msi_data; > + > + /* Read interrupt decode and mask registers */ > + val = pcie_read(port, XILINX_PCIE_REG_IDR); > + mask = pcie_read(port, XILINX_PCIE_REG_IMR); > + > + status = val & mask; > + if (!status) > + return IRQ_NONE; > + > + if (status & XILINX_PCIE_INTR_LINK_DOWN) > + dev_warn(port->dev, "Link Down\n"); > + > + if (status & XILINX_PCIE_INTR_ECRC_ERR) > + dev_warn(port->dev, "ECRC failed\n"); > + > + if (status & XILINX_PCIE_INTR_STR_ERR) > + dev_warn(port->dev, "Streaming error\n"); > + > + if (status & XILINX_PCIE_INTR_HOT_RESET) > + dev_info(port->dev, "Hot reset\n"); > + > + if (status & XILINX_PCIE_INTR_CFG_TIMEOUT) > + dev_warn(port->dev, "ECAM access timeout\n"); > + > + if (status & XILINX_PCIE_INTR_CORRECTABLE) { > + dev_warn(port->dev, "Correctable error message\n"); > + xilinx_pcie_clear_err_interrupts(port); > + } > + > + if (status & XILINX_PCIE_INTR_NONFATAL) { > + dev_warn(port->dev, "Non fatal error message\n"); > + xilinx_pcie_clear_err_interrupts(port); > + } > + > + if (status & XILINX_PCIE_INTR_FATAL) { > + dev_warn(port->dev, "Fatal error message\n"); > + xilinx_pcie_clear_err_interrupts(port); > + } > + > + if (status & XILINX_PCIE_INTR_INTX) { > + /* INTx interrupt received */ > + val = pcie_read(port, XILINX_PCIE_REG_RPIFR1); > + > + /* Check whether interrupt valid */ > + if (!(val & XILINX_PCIE_RPIFR1_INTR_VALID)) { > + dev_warn(port->dev, "RP Intr FIFO1 read error\n"); > + return IRQ_HANDLED; > + } > + > + /* Clear interrupt FIFO register 1 */ > + pcie_write(port, XILINX_PCIE_RPIFR1_ALL_MASK, > + XILINX_PCIE_REG_RPIFR1); > + > + /* Handle INTx Interrupt */ > + val = ((val & XILINX_PCIE_RPIFR1_INTR_MASK) >> > + XILINX_PCIE_RPIFR1_INTR_SHIFT) + 1; > + generic_handle_irq(irq_find_mapping(port->irq_domain, val)); > + } > + > + if (status & XILINX_PCIE_INTR_MSI) { > + /* MSI Interrupt */ > + val = pcie_read(port, XILINX_PCIE_REG_RPIFR1); > + > + if (!(val & XILINX_PCIE_RPIFR1_INTR_VALID)) { > + dev_warn(port->dev, "RP Intr FIFO1 read error\n"); > + return IRQ_HANDLED; > + } > + > + if (val & XILINX_PCIE_RPIFR1_MSI_INTR) { > + msi_data = pcie_read(port, XILINX_PCIE_REG_RPIFR2) & > + XILINX_PCIE_RPIFR2_MSG_DATA; > + > + /* Clear interrupt FIFO register 1 */ > + pcie_write(port, XILINX_PCIE_RPIFR1_ALL_MASK, > + XILINX_PCIE_REG_RPIFR1); > + > + if (IS_ENABLED(CONFIG_PCI_MSI)) { > + /* Handle MSI Interrupt */ > + generic_handle_irq(msi_data); > + } > + } > + } > + > + if (status & XILINX_PCIE_INTR_SLV_UNSUPP) > + dev_warn(port->dev, "Slave unsupported request\n"); > + > + if (status & XILINX_PCIE_INTR_SLV_UNEXP) > + dev_warn(port->dev, "Slave unexpected completion\n"); > + > + if (status & XILINX_PCIE_INTR_SLV_COMPL) > + dev_warn(port->dev, "Slave completion timeout\n"); > + > + if (status & XILINX_PCIE_INTR_SLV_ERRP) > + dev_warn(port->dev, "Slave Error Poison\n"); > + > + if (status & XILINX_PCIE_INTR_SLV_CMPABT) > + dev_warn(port->dev, "Slave Completer Abort\n"); > + > + if (status & XILINX_PCIE_INTR_SLV_ILLBUR) > + dev_warn(port->dev, "Slave Illegal Burst\n"); > + > + if (status & XILINX_PCIE_INTR_MST_DECERR) > + dev_warn(port->dev, "Master decode error\n"); > + > + if (status & XILINX_PCIE_INTR_MST_SLVERR) > + dev_warn(port->dev, "Master slave error\n"); > + > + if (status & XILINX_PCIE_INTR_MST_ERRP) > + dev_warn(port->dev, "Master error poison\n"); > + > + /* Clear the Interrupt Decode register */ > + pcie_write(port, status, XILINX_PCIE_REG_IDR); > + > + return IRQ_HANDLED; > +} > + > +/** > + * xilinx_pcie_free_irq_domain - Free IRQ domain > + * @port: PCIe port information > + */ > +static void xilinx_pcie_free_irq_domain(struct xilinx_pcie_port *port) > +{ > + int i; > + u32 irq, num_irqs; > + > + /* Free IRQ Domain */ > + if (IS_ENABLED(CONFIG_PCI_MSI)) { > + > + free_pages(port->msi_pages, 0); > + > + num_irqs = XILINX_NUM_MSI_IRQS; > + } else { > + /* INTx */ > + num_irqs = 4; > + } > + > + for (i = 0; i < num_irqs; i++) { > + irq = irq_find_mapping(port->irq_domain, i); > + if (irq > 0) > + irq_dispose_mapping(irq); > + } > + > + irq_domain_remove(port->irq_domain); > +} > + > +/** > + * xilinx_pcie_init_irq_domain - Initialize IRQ domain > + * @port: PCIe port information > + * > + * Return: '0' on success and error value on failure > + */ > +static int xilinx_pcie_init_irq_domain(struct xilinx_pcie_port *port) > +{ > + struct device *dev = port->dev; > + struct device_node *node = dev->of_node; > + struct device_node *pcie_intc_node; > + > + /* Setup INTx */ > + pcie_intc_node = of_get_next_child(node, NULL); > + if (!pcie_intc_node) { > + dev_err(dev, "No PCIe Intc node found\n"); > + return PTR_ERR(pcie_intc_node); > + } > + > + port->irq_domain = irq_domain_add_linear(pcie_intc_node, 4, > + &intx_domain_ops, > + port); > + if (!port->irq_domain) { > + dev_err(dev, "Failed to get a INTx IRQ domain\n"); > + return PTR_ERR(port->irq_domain); > + } > + > + /* Setup MSI */ > + if (IS_ENABLED(CONFIG_PCI_MSI)) { > + port->irq_domain = irq_domain_add_linear(node, > + XILINX_NUM_MSI_IRQS, > + &msi_domain_ops, > + &xilinx_pcie_msi_chip); > + if (!port->irq_domain) { > + dev_err(dev, "Failed to get a MSI IRQ domain\n"); > + return PTR_ERR(port->irq_domain); > + } > + > + xilinx_pcie_enable_msi(port); > + } > + > + return 0; > +} > + > +/** > + * xilinx_pcie_init_port - Initialize hardware > + * @port: PCIe port information > + */ > +static void xilinx_pcie_init_port(struct xilinx_pcie_port *port) > +{ > + port->link_up = xilinx_pcie_is_link_up(port); > + if (!port->link_up) I'd use "if (port->link_up)" and reorder the dev_info() to avoid the negation (trivial, I know, but why use the negative when the positive works just as well?) > + dev_info(port->dev, "PCIe Link is DOWN\n"); > + else > + dev_info(port->dev, "PCIe Link is UP\n"); > + > + /* Disable all interrupts*/ > + pcie_write(port, ~XILINX_PCIE_IDR_ALL_MASK, > + XILINX_PCIE_REG_IMR); > + > + /* Clear pending interrupts */ > + pcie_write(port, pcie_read(port, XILINX_PCIE_REG_IDR) & > + XILINX_PCIE_IMR_ALL_MASK, > + XILINX_PCIE_REG_IDR); > + > + /* Enable all interrupts*/ Missing space before "*/" (also on "Disable all interrupts" comment). > + pcie_write(port, XILINX_PCIE_IMR_ALL_MASK, XILINX_PCIE_REG_IMR); > + > + /* Enable the Bridge enable bit */ > + pcie_write(port, pcie_read(port, XILINX_PCIE_REG_RPSC) | > + XILINX_PCIE_REG_RPSC_BEN, > + XILINX_PCIE_REG_RPSC); > +} > + > +/** > + * xilinx_pcie_setup - Setup memory resources > + * @nr: Bus number > + * @sys: Per controller structure > + * > + * Return: '1' on success and error value on failure Incorrect. No point in a comment that explains obvious code anyway. But maybe DocBook requires it, and I guess it's OK then. > + */ > +static int xilinx_pcie_setup(int nr, struct pci_sys_data *sys) > +{ > + struct xilinx_pcie_port *port = sys_to_pcie(sys); > + > + list_splice_init(&port->resources, &sys->resources); > + > + return 1; > +} > + > +/** > + * xilinx_pcie_scan_bus - Scan PCIe bus for devices > + * @nr: Bus number > + * @sys: Per controller structure > + * > + * Return: Valid Bus pointer on success and NULL on failure > + */ > +static struct pci_bus __init *xilinx_pcie_scan_bus(int nr, > + struct pci_sys_data *sys) > +{ > + struct xilinx_pcie_port *port = sys_to_pcie(sys); > + struct pci_bus *bus; > + > + if (port) { I think this test (and the BUG()) is superfluous. I don't think it's possible to get here with sys->private_data == NULL. And if we do, we'll take a null pointer fault and get a nice backtrace anyway. > + port->root_busno = sys->busnr; > + bus = pci_scan_root_bus(port->dev, sys->busnr, &xilinx_pcie_ops, > + sys, &sys->resources); > + } else { > + bus = NULL; > + BUG(); > + } > + > + return bus; > +} > + > + > +/** > + * xilinx_pcie_parse_and_add_res - Add resources by parsing ranges > + * @port: PCIe port information > + * > + * Return: '0' on success and error value on failure > + */ > +static int xilinx_pcie_parse_and_add_res(struct xilinx_pcie_port *port) > +{ > + struct device *dev = port->dev; > + struct device_node *node = dev->of_node; > + struct resource *mem; > + resource_size_t offset; > + struct of_pci_range_parser parser; > + struct of_pci_range range; > + struct pci_host_bridge_window *win; > + int err = 0, mem_resno = 0; > + > + /* Get the ranges */ > + if (of_pci_range_parser_init(&parser, node)) { > + dev_err(dev, "missing \"ranges\" property\n"); > + return -EINVAL; > + } > + > + /* Parse the ranges and add the resources found to the list */ > + for_each_of_pci_range(&parser, &range) { > + > + if (mem_resno >= XILINX_MAX_NUM_RESOURCES) { > + dev_err(dev, "Maximum memory resources exceeded\n"); > + return -EINVAL; > + } > + > + mem = devm_kmalloc(dev, sizeof(*mem), GFP_KERNEL); > + if (!mem) { > + err = -ENOMEM; > + goto free_resources; > + } > + > + of_pci_range_to_resource(&range, node, mem); > + > + switch (mem->flags & IORESOURCE_TYPE_BITS) { > + case IORESOURCE_MEM: > + offset = range.cpu_addr - range.pci_addr; > + mem_resno++; > + break; > + default: > + err = -EINVAL; > + break; > + } > + > + if (err < 0) { > + dev_warn(dev, "Invalid resource found %pR\n", mem); > + continue; > + } > + > + err = request_resource(&iomem_resource, mem); > + if (err) > + goto free_resources; > + > + pci_add_resource_offset(&port->resources, mem, offset); > + } > + > + /* Get the bus range */ > + if (of_pci_parse_bus_range(node, &port->bus_range)) { > + u32 val = pcie_read(port, XILINX_PCIE_REG_BIR); > + u8 last; > + > + last = (val & XILINX_PCIE_BIR_ECAM_SZ_MASK) >> > + XILINX_PCIE_BIR_ECAM_SZ_SHIFT; > + > + port->bus_range = (struct resource) { > + .name = node->name, > + .start = 0, > + .end = last, > + .flags = IORESOURCE_BUS, > + }; > + } > + > + /* Register bus resource */ > + pci_add_resource(&port->resources, &port->bus_range); > + > + return 0; > + > +free_resources: > + release_child_resources(&iomem_resource); > + list_for_each_entry(win, &port->resources, list) > + devm_kfree(dev, win->res); > + pci_free_resource_list(&port->resources); > + > + return err; > +} > + > +/** > + * xilinx_pcie_parse_dt - Parse Device tree > + * @port: PCIe port information > + * > + * Return: '0' on success and error value on failure > + */ > +static int xilinx_pcie_parse_dt(struct xilinx_pcie_port *port) > +{ > + struct device *dev = port->dev; > + struct device_node *node = dev->of_node; > + struct resource regs; > + const char *type; > + int err; > + > + type = of_get_property(node, "device_type", NULL); > + if (!type || strcmp(type, "pci")) { > + dev_err(dev, "invalid \"device_type\" %s\n", type); > + return -EINVAL; > + } > + > + err = of_address_to_resource(node, 0, ®s); > + if (err) { > + dev_err(dev, "missing \"reg\" property\n"); > + return err; > + } > + > + port->reg_base = devm_ioremap_resource(dev, ®s); > + if (IS_ERR(port->reg_base)) > + return PTR_ERR(port->reg_base); > + > + port->irq = irq_of_parse_and_map(node, 0); > + err = devm_request_irq(dev, port->irq, xilinx_pcie_intr_handler, > + IRQF_SHARED, "xilinx-pcie", port); > + if (err) { > + dev_err(dev, "unable to request irq %d\n", port->irq); > + return err; > + } > + > + return 0; > +} > + > +/** > + * xilinx_pcie_probe - Probe function > + * @pdev: Platform device pointer > + * > + * Return: '0' on success and error value on failure > + */ > +static int xilinx_pcie_probe(struct platform_device *pdev) > +{ > + struct xilinx_pcie_port *port; > + struct hw_pci hw; > + struct device *dev = &pdev->dev; > + int err; > + > + if (!dev->of_node) > + return -ENODEV; > + > + port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL); > + if (!port) > + return -ENOMEM; > + > + port->dev = dev; > + > + err = xilinx_pcie_parse_dt(port); > + if (err) { > + dev_err(dev, "Parsing DT failed\n"); > + return err; > + } > + > + xilinx_pcie_init_port(port); > + > + err = xilinx_pcie_init_irq_domain(port); > + if (err) { > + dev_err(dev, "Failed creating IRQ Domain\n"); > + return err; > + } > + > + /* > + * Parse PCI ranges, configuration bus range and > + * request their resources > + */ > + INIT_LIST_HEAD(&port->resources); > + err = xilinx_pcie_parse_and_add_res(port); > + if (err) { > + dev_err(dev, "Failed adding resources\n"); > + return err; > + } > + > + platform_set_drvdata(pdev, port); > + > + /* Register the device */ > + memset(&hw, 0, sizeof(hw)); > + hw = (struct hw_pci) { > + .nr_controllers = 1, > + .private_data = (void **)&port, > + .setup = xilinx_pcie_setup, > + .map_irq = of_irq_parse_and_map_pci, > + .add_bus = xilinx_pcie_add_bus, > + .scan = xilinx_pcie_scan_bus, > + .ops = &xilinx_pcie_ops, > + }; > + pci_common_init_dev(dev, &hw); > + > + return 0; > +} > + > +/** > + * xilinx_pcie_remove - Remove function > + * @pdev: Platform device pointer > + * > + * Return: '0' always > + */ > +static int xilinx_pcie_remove(struct platform_device *pdev) > +{ > + struct xilinx_pcie_port *port = platform_get_drvdata(pdev); > + > + xilinx_pcie_free_irq_domain(port); > + > + return 0; > +} > + > +static struct of_device_id xilinx_pcie_of_match[] = { > + { .compatible = "xlnx,axi-pcie-host-1.00.a", }, > + {} > +}; > + > +static struct platform_driver xilinx_pcie_driver = { > + .driver = { > + .name = "xilinx-pcie", > + .owner = THIS_MODULE, > + .of_match_table = xilinx_pcie_of_match, > + .suppress_bind_attrs = true, > + }, > + .probe = xilinx_pcie_probe, > + .remove = xilinx_pcie_remove, > +}; > +module_platform_driver(xilinx_pcie_driver); > + > +MODULE_AUTHOR("Xilinx Inc"); > +MODULE_DESCRIPTION("Xilinx AXI PCIe driver"); > +MODULE_LICENSE("GPLv2"); I think you want "GPL v2" here (with the space; see license_is_gpl_compatible()). -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/