[PATCH v6] PCI: Layerscape: Add Layerscape PCIe driver
Kumar Gala
galak at codeaurora.org
Fri Oct 17 00:43:18 PDT 2014
On Oct 17, 2014, at 9:18 AM, Minghuan.Lian at freescale.com wrote:
> Hi Kumar,
>
> Currently the code supports multiple controllers.
> LS1021A contains two controllers and both can work well.
There are other comments I made for the code. Also, it seems like you have locking issues (or lack of locking) around what appears to be a shared MSI region for both controllers.
>
> Thanks,
> Minghuan
>
> ________________________________________
> 发件人: Kumar Gala <galak at codeaurora.org>
> 发送时间: 2014年10月16日 22:41
> 收件人: Lian Minghuan-B31939
> 抄送: linux-pci at vger.kernel.org; Arnd Bergmann; Hu Mingkai-B21284; Zang Roy-R61911; Bjorn Helgaas; linux-arm-kernel at lists.infradead.org
> 主题: Re: [PATCH v6] PCI: Layerscape: Add Layerscape PCIe driver
>
> On Oct 14, 2014, at 12:18 PM, Minghuan Lian <Minghuan.Lian at freescale.com> 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>
>
> 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 <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
>> +
>> 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 <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 <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 <Minghuan.Lian at freescale.com>");
>> +MODULE_DESCRIPTION("Freescale Layerscape PCIe host controller driver");
>> +MODULE_LICENSE("GPL v2");
>> --
>> 1.9.1
>>
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel at lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
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