[PATCH v6] PCI: Layerscape: Add Layerscape PCIe driver
Bjorn Helgaas
bhelgaas at google.com
Thu Nov 13 08:38:33 PST 2014
On Wed, Nov 05, 2014 at 04:45:11PM +0800, Minghuan Lian wrote:
> Add support for Freescale Layerscape PCIe controller. This driver
> re-uses the designware core code.
>
> Signed-off-by: Minghuan Lian <Minghuan.Lian at freescale.com>
Applied with Arnd's ack to pci/host-layerscape for v3.19, thanks!
> ---
> Based on pci-next branch
>
> Change log:
> v6:
> 1. remove MSI support. MSI driver will be implemented in a separate file
> 2. remove bitrev() because SCFG is set bit reverse mode as default.
>
> v5:
> 1. Add MAINTAINERS information
> 2. Remove unnecessary NULL pointer check
> 3. Use dev_dbg instead of dev_err in ls_pcie_msi_irq_handler()
>
> v4:
> 1. Add 'depends on OF' to Kconfig
>
> v3:
> 1. Add prefechable mem region and adjust mem region
> 2. Rename 'pcie-scfg' to 'fsl,pcie-scfg'
> 3. Change MSI interrupt handler
> 4. Use module_platform_driver_probe instead of subsys_initcall
>
> v2:
> 1. Add pcie-scfg to link scfg device node and remove "fsl, ls-pcie" compatible
> 2. Use regmap API to access scfg.
> 3. remove ls1021 PCI device ID.
> 4. remove unused irq pme_irq and ls_pcie_list.
> 5. Do not set scfg bit reverse mode
>
> .../devicetree/bindings/pci/layerscape-pci.txt | 42 +++++
> MAINTAINERS | 10 ++
> drivers/pci/host/Kconfig | 8 +
> drivers/pci/host/Makefile | 1 +
> drivers/pci/host/pci-layerscape.c | 179 +++++++++++++++++++++
> 5 files changed, 240 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/pci/layerscape-pci.txt
> create mode 100644 drivers/pci/host/pci-layerscape.c
>
> diff --git a/Documentation/devicetree/bindings/pci/layerscape-pci.txt b/Documentation/devicetree/bindings/pci/layerscape-pci.txt
> new file mode 100644
> index 0000000..40749eb
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/layerscape-pci.txt
> @@ -0,0 +1,42 @@
> +Freescale Layerscape PCIe controller
> +
> +This PCIe host controller is based on the Synopsis Designware PCIe IP
> +and thus inherits all the common properties defined in designware-pcie.txt.
> +
> +Required properties:
> +- compatible: should contain the platform identifier such as "fsl,ls1021a-pcie"
> +- reg: base addresses and lengths of the PCIe controller
> +- interrupts: A list of interrupt outputs of the controller. Must contain an
> + entry for each entry in the interrupt-names property.
> +- interrupt-names: Must include the following entries:
> + "intr": The interrupt that is asserted for controller interrupts
> +- fsl,pcie-scfg: Must include two entries.
> + The first entry must be a link to the SCFG device node
> + The second entry must be '0' or '1' based on physical PCIe controller index.
> + used to get SCFG PEXN registers
> +
> +Example:
> +
> + pcie at 3400000 {
> + compatible = "fsl,ls1021a-pcie", "snps,dw-pcie";
> + reg = <0x00 0x03400000 0x0 0x00010000 /* controller registers */
> + 0x40 0x00000000 0x0 0x00002000>; /* configuration space */
> + reg-names = "regs", "config";
> + interrupts = <GIC_SPI 177 IRQ_TYPE_LEVEL_HIGH>; /* controller interrupt */
> + interrupt-names = "intr";
> + fsl,pcie-scfg = <&scfg 0>;
> + #address-cells = <3>;
> + #size-cells = <2>;
> + device_type = "pci";
> + num-lanes = <4>;
> + bus-range = <0x0 0xff>;
> + ranges = <0x81000000 0x0 0x00000000 0x40 0x00010000 0x0 0x00010000 /* downstream I/O */
> + 0xc2000000 0x0 0x20000000 0x40 0x20000000 0x0 0x20000000 /* prefetchable memory */
> + 0x82000000 0x0 0x40000000 0x40 0x40000000 0x0 0x40000000>; /* non-prefetchable memory */
> + #interrupt-cells = <1>;
> + interrupt-map-mask = <0 0 0 7>;
> + interrupt-map = <0000 0 0 1 &gic GIC_SPI 91 IRQ_TYPE_LEVEL_HIGH>,
> + <0000 0 0 2 &gic GIC_SPI 188 IRQ_TYPE_LEVEL_HIGH>,
> + <0000 0 0 3 &gic GIC_SPI 190 IRQ_TYPE_LEVEL_HIGH>,
> + <0000 0 0 4 &gic GIC_SPI 192 IRQ_TYPE_LEVEL_HIGH>;
> + };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index a20df9b..7853d1b 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -6983,6 +6983,16 @@ S: Maintained
> F: Documentation/devicetree/bindings/pci/xgene-pci.txt
> F: drivers/pci/host/pci-xgene.c
>
> +PCIe DRIVER FOR FREESCALE LAYERSCAPE
> +M: Minghuan Lian <minghuan.Lian at freescale.com>
> +M: Mingkai Hu <mingkai.hu at freescale.com>
> +M: Roy Zang <tie-fei.zang at freescale.com>
> +L: linuxppc-dev at lists.ozlabs.org
> +L: linux-pci at vger.kernel.org
> +L: linux-arm-kernel at lists.infradead.org
> +S: Maintained
> +F: drivers/pci/host/pci-layerscape.c
> +
> PCI DRIVER FOR IMX6
> M: Richard Zhu <r65037 at freescale.com>
> M: Lucas Stach <l.stach at pengutronix.de>
> diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
> index 3dc25fa..8ac69aa 100644
> --- a/drivers/pci/host/Kconfig
> +++ b/drivers/pci/host/Kconfig
> @@ -91,4 +91,12 @@ config PCI_XGENE
> There are 5 internal PCIe ports available. Each port is GEN3 capable
> and have varied lanes from x1 to x8.
>
> +config PCI_LAYERSCAPE
> + bool "Freescale Layerscape PCIe controller"
> + depends on OF
> + select PCIE_DW
> + select MFD_SYSCON
> + help
> + Say Y here if you want PCIe controller support on Layerscape SoCs.
> +
> endmenu
> diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
> index 26b3461..44c2699 100644
> --- a/drivers/pci/host/Makefile
> +++ b/drivers/pci/host/Makefile
> @@ -11,3 +11,4 @@ obj-$(CONFIG_PCIE_SPEAR13XX) += pcie-spear13xx.o
> obj-$(CONFIG_PCI_KEYSTONE) += pci-keystone-dw.o pci-keystone.o
> obj-$(CONFIG_PCIE_XILINX) += pcie-xilinx.o
> obj-$(CONFIG_PCI_XGENE) += pci-xgene.o
> +obj-$(CONFIG_PCI_LAYERSCAPE) += pci-layerscape.o
> diff --git a/drivers/pci/host/pci-layerscape.c b/drivers/pci/host/pci-layerscape.c
> new file mode 100644
> index 0000000..6697b1a
> --- /dev/null
> +++ b/drivers/pci/host/pci-layerscape.c
> @@ -0,0 +1,179 @@
> +/*
> + * PCIe host controller driver for Freescale Layerscape SoCs
> + *
> + * Copyright (C) 2014 Freescale Semiconductor.
> + *
> + * Author: Minghuan Lian <Minghuan.Lian at freescale.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/of_pci.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_address.h>
> +#include <linux/pci.h>
> +#include <linux/platform_device.h>
> +#include <linux/resource.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/regmap.h>
> +
> +#include "pcie-designware.h"
> +
> +/* PEX1/2 Misc Ports Status Register */
> +#define SCFG_PEXMSCPORTSR(pex_idx) (0x94 + (pex_idx) * 4)
> +#define LTSSM_STATE_SHIFT 20
> +#define LTSSM_STATE_MASK 0x3f
> +#define LTSSM_PCIE_L0 0x11 /* L0 state */
> +
> +/* Symbol Timer Register and Filter Mask Register 1 */
> +#define PCIE_STRFMR1 0x71c
> +
> +struct ls_pcie {
> + struct list_head node;
> + struct device *dev;
> + struct pci_bus *bus;
> + void __iomem *dbi;
> + struct regmap *scfg;
> + struct pcie_port pp;
> + int index;
> + int msi_irq;
> +};
> +
> +#define to_ls_pcie(x) container_of(x, struct ls_pcie, pp)
> +
> +static int ls_pcie_link_up(struct pcie_port *pp)
> +{
> + u32 state;
> + struct ls_pcie *pcie = to_ls_pcie(pp);
> +
> + regmap_read(pcie->scfg, SCFG_PEXMSCPORTSR(pcie->index), &state);
> + state = (state >> LTSSM_STATE_SHIFT) & LTSSM_STATE_MASK;
> +
> + if (state < LTSSM_PCIE_L0)
> + return 0;
> +
> + return 1;
> +}
> +
> +static void ls_pcie_host_init(struct pcie_port *pp)
> +{
> + struct ls_pcie *pcie = to_ls_pcie(pp);
> + int count = 0;
> + u32 val;
> +
> + dw_pcie_setup_rc(pp);
> +
> + while (!ls_pcie_link_up(pp)) {
> + usleep_range(100, 1000);
> + count++;
> + if (count >= 200) {
> + dev_err(pp->dev, "phy link never came up\n");
> + return;
> + }
> + }
> +
> + /*
> + * LS1021A Workaround for internal TKT228622
> + * to fix the INTx hang issue
> + */
> + val = ioread32(pcie->dbi + PCIE_STRFMR1);
> + val &= 0xffff;
> + iowrite32(val, pcie->dbi + PCIE_STRFMR1);
> +}
> +
> +static struct pcie_host_ops ls_pcie_host_ops = {
> + .link_up = ls_pcie_link_up,
> + .host_init = ls_pcie_host_init,
> +};
> +
> +static int ls_add_pcie_port(struct ls_pcie *pcie)
> +{
> + struct pcie_port *pp;
> + int ret;
> +
> + pp = &pcie->pp;
> + pp->dev = pcie->dev;
> + pp->dbi_base = pcie->dbi;
> + pp->root_bus_nr = -1;
> + pp->ops = &ls_pcie_host_ops;
> +
> + ret = dw_pcie_host_init(pp);
> + if (ret) {
> + dev_err(pp->dev, "failed to initialize host\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int __init ls_pcie_probe(struct platform_device *pdev)
> +{
> + struct ls_pcie *pcie;
> + struct resource *dbi_base;
> + u32 index[2];
> + int ret;
> +
> + pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
> + if (!pcie)
> + return -ENOMEM;
> +
> + pcie->dev = &pdev->dev;
> +
> + dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
> + if (!dbi_base) {
> + dev_err(&pdev->dev, "missing *regs* space\n");
> + return -ENODEV;
> + }
> +
> + pcie->dbi = devm_ioremap_resource(&pdev->dev, dbi_base);
> + if (IS_ERR(pcie->dbi))
> + return PTR_ERR(pcie->dbi);
> +
> + pcie->scfg = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
> + "fsl,pcie-scfg");
> + if (IS_ERR(pcie->scfg)) {
> + dev_err(&pdev->dev, "No syscfg phandle specified\n");
> + return PTR_ERR(pcie->scfg);
> + }
> +
> + ret = of_property_read_u32_array(pdev->dev.of_node,
> + "fsl,pcie-scfg", index, 2);
> + if (ret)
> + return ret;
> + pcie->index = index[1];
> +
> + ret = ls_add_pcie_port(pcie);
> + if (ret < 0)
> + return ret;
> +
> + platform_set_drvdata(pdev, pcie);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id ls_pcie_of_match[] = {
> + { .compatible = "fsl,ls1021a-pcie" },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, ls_pcie_of_match);
> +
> +static struct platform_driver ls_pcie_driver = {
> + .driver = {
> + .name = "layerscape-pcie",
> + .owner = THIS_MODULE,
> + .of_match_table = ls_pcie_of_match,
> + },
> +};
> +
> +module_platform_driver_probe(ls_pcie_driver, ls_pcie_probe);
> +
> +MODULE_AUTHOR("Minghuan Lian <Minghuan.Lian at freescale.com>");
> +MODULE_DESCRIPTION("Freescale Layerscape PCIe host controller driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.9.1
>
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