Subject: 答复: [PATCH v6] PCI: Layerscape: Add Layerscape PCIe driver

From: [email-masked] (Minghuan.Lian at freescale.com)
Date: Fri, 17 Oct 2014 07:18:09 +0000

Hi Kumar,

Currently the code supports multiple controllers.
LS1021A contains two controllers and both can work well.

Thanks,
Minghuan

________________________________________
???: Kumar Gala <[email-masked]>
????: 2014?10?16? 22:41
???: Lian Minghuan-B31939
??: linux-pci at vger.kernel.org; Arnd Bergmann; Hu Mingkai-B21284; Zang Roy-R61911; Bjorn Helgaas; linux-arm-kernel at lists.infradead.org
??: Re: [PATCH v6] PCI: Layerscape: Add Layerscape PCIe driver

On Oct 14, 2014, at 12:18 PM, Minghuan Lian <[email-masked]> wrote:

> Add support for Freescale Layerscape PCIe controller. This driver
> re-uses the designware core code.
>
> Signed-off-by: Minghuan Lian <[email-masked]>

Do you support multiple controllers or just one?  I feel like the DWC PCIe core code needs changes to handle multiple controllers?

> ---
> Change log:
> v6:
> 1. Delete unnecessary if statement in ls_pcie_host_init()
>
> v5:
> 1. Add MAINTAINERS information
> 2. Remove nnnecessary 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     |  46 ++++
> MAINTAINERS                                        |  10 +
> drivers/pci/host/Kconfig                           |   8 +
> drivers/pci/host/Makefile                          |   1 +
> drivers/pci/host/pci-layerscape.c                  | 269 +++++++++++++++++++++
> 5 files changed, 334 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..d7b0026
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/layerscape-pci.txt
> @@ -0,0 +1,46 @@
> +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
> +  "msi": The interrupt that is asserted when an MSI is received
> +  "pme": The interrupt that is asserted when PME state changes
> +- 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 */
> +                          <GIC_SPI 179 IRQ_TYPE_LEVEL_HIGH>, /* MSI interrupt */
> +                          <GIC_SPI 181 IRQ_TYPE_LEVEL_HIGH>; /* PME interrupt */
> +             interrupt-names = "intr", "msi", "pme";
> +             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 1ff06de..b6237ab 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -6936,6 +6936,16 @@ L:     linux-pci at vger.kernel.org
> S:    Maintained
> F:    drivers/pci/host/*spear*
>
> +PCIe DRIVER FOR FREESCALE LAYERSCAPE
> +M:   Minghuan Lian <[email-masked]>
> +M:   Mingkai Hu <[email-masked]>
> +M:   Roy Zang <[email-masked]>
> +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
> +
> PCMCIA SUBSYSTEM
> P:    Linux PCMCIA Team
> L:    linux-pcmcia at lists.infradead.org
> diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
> index 8922c37..4788fb3 100644
> --- a/drivers/pci/host/Kconfig
> +++ b/drivers/pci/host/Kconfig
> @@ -63,4 +63,12 @@ config PCIE_SPEAR13XX
>       help
>         Say Y here if you want PCIe support on SPEAr13XX SoCs.
>
> +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 d0e88f1..54cd9b2 100644
> --- a/drivers/pci/host/Makefile
> +++ b/drivers/pci/host/Makefile
> @@ -8,3 +8,4 @@ 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_PCIE_SPEAR13XX) += pcie-spear13xx.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..a459de2
> --- /dev/null
> +++ b/drivers/pci/host/pci-layerscape.c
> @@ -0,0 +1,269 @@
> +/*
> + * PCIe host controller driver for Freescale Layerscape SoCs
> + *
> + * Copyright (C) 2014 Freescale Semiconductor.
> + *
> +  * Author: Minghuan Lian <[email-masked]>
> + *
> + * 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 <linux/bitrev.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 */
> +
> +/* SCFG MSI register */
> +#define SCFG_SPIMSICR                0x40
> +#define SCFG_SPIMSICLRCR     0x90
> +
> +#define MSI_LS1021A_ADDR             0x1570040

This shouldn?t be hard coded, should be coming from DT.

> +#define MSI_LS1021A_DATA(pex_idx)    (0xb3 + pex_idx)
> +
> +/* 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 = bitrev32(state);
> +     state = (state >> LTSSM_STATE_SHIFT) & LTSSM_STATE_MASK;
> +
> +     if (state < LTSSM_PCIE_L0)
> +             return 0;
> +
> +     return 1;
> +}
> +
> +static u32 ls_pcie_get_msi_addr(struct pcie_port *pp)
> +{
> +     return MSI_LS1021A_ADDR;
> +}
> +
> +static u32 ls_pcie_get_msi_data(struct pcie_port *pp, int pos)
> +{
> +     struct ls_pcie *pcie = to_ls_pcie(pp);
> +
> +     return MSI_LS1021A_DATA(pcie->index);
> +}
> +
> +static irqreturn_t ls_pcie_msi_irq_handler(int irq, void *data)
> +{
> +     struct pcie_port *pp = data;
> +     struct ls_pcie *pcie = to_ls_pcie(pp);
> +     unsigned int msi_irq;
> +
> +     /* clear the interrupt */
> +     regmap_write(pcie->scfg, SCFG_SPIMSICLRCR,
> +                  MSI_LS1021A_DATA(pcie->index));
> +
> +     msi_irq = irq_find_mapping(pp->irq_domain, 0);
> +     if (!msi_irq) {
> +             /*
> +              * that's weird who triggered this?
> +              * just clear it
> +              */
> +             dev_dbg(pcie->dev, "unexpected MSI\n");
> +             return IRQ_NONE;
> +     }
> +
> +     generic_handle_irq(msi_irq);
> +     return IRQ_HANDLED;
> +}
> +
> +static void ls_pcie_msi_clear_irq(struct pcie_port *pp, int irq)
> +{
> +}
> +
> +static void ls_pcie_msi_set_irq(struct pcie_port *pp, int irq)
> +{
> +}
> +
> +static void ls1021a_pcie_msi_fixup(struct pcie_port *pp)
> +{
> +     int i;
> +
> +     /*
> +      * LS1021A has only one MSI interrupt
> +      * Set all msi interrupts as used except the first one
> +      */
> +     for (i = 1; i < MAX_MSI_IRQS; i++)
> +             set_bit(i, pp->msi_irq_in_use);
> +}
> +
> +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);

Is this something that will be fixed for production silicon?  If so it should probably not exist for upstream code.

> +
> +     ls1021a_pcie_msi_fixup(pp);
> +}
> +
> +static struct pcie_host_ops ls_pcie_host_ops = {
> +     .link_up = ls_pcie_link_up,
> +     .host_init = ls_pcie_host_init,
> +     .msi_set_irq = ls_pcie_msi_set_irq,
> +     .msi_clear_irq = ls_pcie_msi_clear_irq,
> +     .get_msi_addr = ls_pcie_get_msi_addr,
> +     .get_msi_data = ls_pcie_get_msi_data,
> +};
> +
> +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->msi_irq = pcie->msi_irq;
> +
> +     if (IS_ENABLED(CONFIG_PCI_MSI)) {
> +             ret = devm_request_irq(pp->dev, pp->msi_irq,
> +                                     ls_pcie_msi_irq_handler,
> +                                     IRQF_SHARED, "ls-pcie-msi", pp);
> +             if (ret) {
> +                     dev_err(pp->dev, "failed to request msi irq\n");
> +                     return ret;
> +             }
> +     }
> +
> +     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];
> +
> +     pcie->msi_irq = platform_get_irq_byname(pdev, "msi");
> +     if (pcie->msi_irq < 0) {
> +             dev_err(&pdev->dev,
> +                     "failed to get MSI IRQ: %d\n", pcie->msi_irq);
> +             return pcie->msi_irq;
> +     }
> +
> +     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 <[email-masked]>");
> +MODULE_DESCRIPTION("Freescale Layerscape PCIe host controller driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.9.1
>
>
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> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

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