diff options
Diffstat (limited to 'kernel/drivers/pci/host/pci-layerscape.c')
-rw-r--r-- | kernel/drivers/pci/host/pci-layerscape.c | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/kernel/drivers/pci/host/pci-layerscape.c b/kernel/drivers/pci/host/pci-layerscape.c new file mode 100644 index 000000000..4a6e62f67 --- /dev/null +++ b/kernel/drivers/pci/host/pci-layerscape.c @@ -0,0 +1,175 @@ +/* + * PCIe host controller driver for Freescale Layerscape SoCs + * + * Copyright (C) 2014 Freescale Semiconductor. + * + * Author: Minghuan Lian <Minghuan.Lian@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"); + pcie->dbi = devm_ioremap_resource(&pdev->dev, dbi_base); + if (IS_ERR(pcie->dbi)) { + dev_err(&pdev->dev, "missing *regs* space\n"); + 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", + .of_match_table = ls_pcie_of_match, + }, +}; + +module_platform_driver_probe(ls_pcie_driver, ls_pcie_probe); + +MODULE_AUTHOR("Minghuan Lian <Minghuan.Lian@freescale.com>"); +MODULE_DESCRIPTION("Freescale Layerscape PCIe host controller driver"); +MODULE_LICENSE("GPL v2"); |