diff options
Diffstat (limited to 'drivers/pci/controller/dwc/pcie-uniphier.c')
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-uniphier.c | 409 |
1 files changed, 409 insertions, 0 deletions
diff --git a/drivers/pci/controller/dwc/pcie-uniphier.c b/drivers/pci/controller/dwc/pcie-uniphier.c new file mode 100644 index 000000000..48c3eba81 --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-uniphier.c @@ -0,0 +1,409 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCIe host controller driver for UniPhier SoCs + * Copyright 2018 Socionext Inc. + * Author: Kunihiko Hayashi <hayashi.kunihiko@socionext.com> + */ + +#include <linux/bitops.h> +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/iopoll.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/irqdomain.h> +#include <linux/of_irq.h> +#include <linux/pci.h> +#include <linux/phy/phy.h> +#include <linux/platform_device.h> +#include <linux/reset.h> + +#include "pcie-designware.h" + +#define PCL_PINCTRL0 0x002c +#define PCL_PERST_PLDN_REGEN BIT(12) +#define PCL_PERST_NOE_REGEN BIT(11) +#define PCL_PERST_OUT_REGEN BIT(8) +#define PCL_PERST_PLDN_REGVAL BIT(4) +#define PCL_PERST_NOE_REGVAL BIT(3) +#define PCL_PERST_OUT_REGVAL BIT(0) + +#define PCL_PIPEMON 0x0044 +#define PCL_PCLK_ALIVE BIT(15) + +#define PCL_MODE 0x8000 +#define PCL_MODE_REGEN BIT(8) +#define PCL_MODE_REGVAL BIT(0) + +#define PCL_APP_READY_CTRL 0x8008 +#define PCL_APP_LTSSM_ENABLE BIT(0) + +#define PCL_APP_PM0 0x8078 +#define PCL_SYS_AUX_PWR_DET BIT(8) + +#define PCL_RCV_INT 0x8108 +#define PCL_RCV_INT_ALL_ENABLE GENMASK(20, 17) +#define PCL_CFG_BW_MGT_STATUS BIT(4) +#define PCL_CFG_LINK_AUTO_BW_STATUS BIT(3) +#define PCL_CFG_AER_RC_ERR_MSI_STATUS BIT(2) +#define PCL_CFG_PME_MSI_STATUS BIT(1) + +#define PCL_RCV_INTX 0x810c +#define PCL_RCV_INTX_ALL_ENABLE GENMASK(19, 16) +#define PCL_RCV_INTX_ALL_MASK GENMASK(11, 8) +#define PCL_RCV_INTX_MASK_SHIFT 8 +#define PCL_RCV_INTX_ALL_STATUS GENMASK(3, 0) +#define PCL_RCV_INTX_STATUS_SHIFT 0 + +#define PCL_STATUS_LINK 0x8140 +#define PCL_RDLH_LINK_UP BIT(1) +#define PCL_XMLH_LINK_UP BIT(0) + +struct uniphier_pcie { + struct dw_pcie pci; + void __iomem *base; + struct clk *clk; + struct reset_control *rst; + struct phy *phy; + struct irq_domain *legacy_irq_domain; +}; + +#define to_uniphier_pcie(x) dev_get_drvdata((x)->dev) + +static void uniphier_pcie_ltssm_enable(struct uniphier_pcie *pcie, + bool enable) +{ + u32 val; + + val = readl(pcie->base + PCL_APP_READY_CTRL); + if (enable) + val |= PCL_APP_LTSSM_ENABLE; + else + val &= ~PCL_APP_LTSSM_ENABLE; + writel(val, pcie->base + PCL_APP_READY_CTRL); +} + +static void uniphier_pcie_init_rc(struct uniphier_pcie *pcie) +{ + u32 val; + + /* set RC MODE */ + val = readl(pcie->base + PCL_MODE); + val |= PCL_MODE_REGEN; + val &= ~PCL_MODE_REGVAL; + writel(val, pcie->base + PCL_MODE); + + /* use auxiliary power detection */ + val = readl(pcie->base + PCL_APP_PM0); + val |= PCL_SYS_AUX_PWR_DET; + writel(val, pcie->base + PCL_APP_PM0); + + /* assert PERST# */ + val = readl(pcie->base + PCL_PINCTRL0); + val &= ~(PCL_PERST_NOE_REGVAL | PCL_PERST_OUT_REGVAL + | PCL_PERST_PLDN_REGVAL); + val |= PCL_PERST_NOE_REGEN | PCL_PERST_OUT_REGEN + | PCL_PERST_PLDN_REGEN; + writel(val, pcie->base + PCL_PINCTRL0); + + uniphier_pcie_ltssm_enable(pcie, false); + + usleep_range(100000, 200000); + + /* deassert PERST# */ + val = readl(pcie->base + PCL_PINCTRL0); + val |= PCL_PERST_OUT_REGVAL | PCL_PERST_OUT_REGEN; + writel(val, pcie->base + PCL_PINCTRL0); +} + +static int uniphier_pcie_wait_rc(struct uniphier_pcie *pcie) +{ + u32 status; + int ret; + + /* wait PIPE clock */ + ret = readl_poll_timeout(pcie->base + PCL_PIPEMON, status, + status & PCL_PCLK_ALIVE, 100000, 1000000); + if (ret) { + dev_err(pcie->pci.dev, + "Failed to initialize controller in RC mode\n"); + return ret; + } + + return 0; +} + +static int uniphier_pcie_link_up(struct dw_pcie *pci) +{ + struct uniphier_pcie *pcie = to_uniphier_pcie(pci); + u32 val, mask; + + val = readl(pcie->base + PCL_STATUS_LINK); + mask = PCL_RDLH_LINK_UP | PCL_XMLH_LINK_UP; + + return (val & mask) == mask; +} + +static int uniphier_pcie_start_link(struct dw_pcie *pci) +{ + struct uniphier_pcie *pcie = to_uniphier_pcie(pci); + + uniphier_pcie_ltssm_enable(pcie, true); + + return 0; +} + +static void uniphier_pcie_stop_link(struct dw_pcie *pci) +{ + struct uniphier_pcie *pcie = to_uniphier_pcie(pci); + + uniphier_pcie_ltssm_enable(pcie, false); +} + +static void uniphier_pcie_irq_enable(struct uniphier_pcie *pcie) +{ + writel(PCL_RCV_INT_ALL_ENABLE, pcie->base + PCL_RCV_INT); + writel(PCL_RCV_INTX_ALL_ENABLE, pcie->base + PCL_RCV_INTX); +} + + +static void uniphier_pcie_irq_mask(struct irq_data *d) +{ + struct dw_pcie_rp *pp = irq_data_get_irq_chip_data(d); + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct uniphier_pcie *pcie = to_uniphier_pcie(pci); + unsigned long flags; + u32 val; + + raw_spin_lock_irqsave(&pp->lock, flags); + + val = readl(pcie->base + PCL_RCV_INTX); + val |= BIT(irqd_to_hwirq(d) + PCL_RCV_INTX_MASK_SHIFT); + writel(val, pcie->base + PCL_RCV_INTX); + + raw_spin_unlock_irqrestore(&pp->lock, flags); +} + +static void uniphier_pcie_irq_unmask(struct irq_data *d) +{ + struct dw_pcie_rp *pp = irq_data_get_irq_chip_data(d); + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct uniphier_pcie *pcie = to_uniphier_pcie(pci); + unsigned long flags; + u32 val; + + raw_spin_lock_irqsave(&pp->lock, flags); + + val = readl(pcie->base + PCL_RCV_INTX); + val &= ~BIT(irqd_to_hwirq(d) + PCL_RCV_INTX_MASK_SHIFT); + writel(val, pcie->base + PCL_RCV_INTX); + + raw_spin_unlock_irqrestore(&pp->lock, flags); +} + +static struct irq_chip uniphier_pcie_irq_chip = { + .name = "PCI", + .irq_mask = uniphier_pcie_irq_mask, + .irq_unmask = uniphier_pcie_irq_unmask, +}; + +static int uniphier_pcie_intx_map(struct irq_domain *domain, unsigned int irq, + irq_hw_number_t hwirq) +{ + irq_set_chip_and_handler(irq, &uniphier_pcie_irq_chip, + handle_level_irq); + irq_set_chip_data(irq, domain->host_data); + + return 0; +} + +static const struct irq_domain_ops uniphier_intx_domain_ops = { + .map = uniphier_pcie_intx_map, +}; + +static void uniphier_pcie_irq_handler(struct irq_desc *desc) +{ + struct dw_pcie_rp *pp = irq_desc_get_handler_data(desc); + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct uniphier_pcie *pcie = to_uniphier_pcie(pci); + struct irq_chip *chip = irq_desc_get_chip(desc); + unsigned long reg; + u32 val, bit; + + /* INT for debug */ + val = readl(pcie->base + PCL_RCV_INT); + + if (val & PCL_CFG_BW_MGT_STATUS) + dev_dbg(pci->dev, "Link Bandwidth Management Event\n"); + if (val & PCL_CFG_LINK_AUTO_BW_STATUS) + dev_dbg(pci->dev, "Link Autonomous Bandwidth Event\n"); + if (val & PCL_CFG_AER_RC_ERR_MSI_STATUS) + dev_dbg(pci->dev, "Root Error\n"); + if (val & PCL_CFG_PME_MSI_STATUS) + dev_dbg(pci->dev, "PME Interrupt\n"); + + writel(val, pcie->base + PCL_RCV_INT); + + /* INTx */ + chained_irq_enter(chip, desc); + + val = readl(pcie->base + PCL_RCV_INTX); + reg = FIELD_GET(PCL_RCV_INTX_ALL_STATUS, val); + + for_each_set_bit(bit, ®, PCI_NUM_INTX) + generic_handle_domain_irq(pcie->legacy_irq_domain, bit); + + chained_irq_exit(chip, desc); +} + +static int uniphier_pcie_config_legacy_irq(struct dw_pcie_rp *pp) +{ + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct uniphier_pcie *pcie = to_uniphier_pcie(pci); + struct device_node *np = pci->dev->of_node; + struct device_node *np_intc; + int ret = 0; + + np_intc = of_get_child_by_name(np, "legacy-interrupt-controller"); + if (!np_intc) { + dev_err(pci->dev, "Failed to get legacy-interrupt-controller node\n"); + return -EINVAL; + } + + pp->irq = irq_of_parse_and_map(np_intc, 0); + if (!pp->irq) { + dev_err(pci->dev, "Failed to get an IRQ entry in legacy-interrupt-controller\n"); + ret = -EINVAL; + goto out_put_node; + } + + pcie->legacy_irq_domain = irq_domain_add_linear(np_intc, PCI_NUM_INTX, + &uniphier_intx_domain_ops, pp); + if (!pcie->legacy_irq_domain) { + dev_err(pci->dev, "Failed to get INTx domain\n"); + ret = -ENODEV; + goto out_put_node; + } + + irq_set_chained_handler_and_data(pp->irq, uniphier_pcie_irq_handler, + pp); + +out_put_node: + of_node_put(np_intc); + return ret; +} + +static int uniphier_pcie_host_init(struct dw_pcie_rp *pp) +{ + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct uniphier_pcie *pcie = to_uniphier_pcie(pci); + int ret; + + ret = uniphier_pcie_config_legacy_irq(pp); + if (ret) + return ret; + + uniphier_pcie_irq_enable(pcie); + + return 0; +} + +static const struct dw_pcie_host_ops uniphier_pcie_host_ops = { + .host_init = uniphier_pcie_host_init, +}; + +static int uniphier_pcie_host_enable(struct uniphier_pcie *pcie) +{ + int ret; + + ret = clk_prepare_enable(pcie->clk); + if (ret) + return ret; + + ret = reset_control_deassert(pcie->rst); + if (ret) + goto out_clk_disable; + + uniphier_pcie_init_rc(pcie); + + ret = phy_init(pcie->phy); + if (ret) + goto out_rst_assert; + + ret = uniphier_pcie_wait_rc(pcie); + if (ret) + goto out_phy_exit; + + return 0; + +out_phy_exit: + phy_exit(pcie->phy); +out_rst_assert: + reset_control_assert(pcie->rst); +out_clk_disable: + clk_disable_unprepare(pcie->clk); + + return ret; +} + +static const struct dw_pcie_ops dw_pcie_ops = { + .start_link = uniphier_pcie_start_link, + .stop_link = uniphier_pcie_stop_link, + .link_up = uniphier_pcie_link_up, +}; + +static int uniphier_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct uniphier_pcie *pcie; + int ret; + + pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL); + if (!pcie) + return -ENOMEM; + + pcie->pci.dev = dev; + pcie->pci.ops = &dw_pcie_ops; + + pcie->base = devm_platform_ioremap_resource_byname(pdev, "link"); + if (IS_ERR(pcie->base)) + return PTR_ERR(pcie->base); + + pcie->clk = devm_clk_get(dev, NULL); + if (IS_ERR(pcie->clk)) + return PTR_ERR(pcie->clk); + + pcie->rst = devm_reset_control_get_shared(dev, NULL); + if (IS_ERR(pcie->rst)) + return PTR_ERR(pcie->rst); + + pcie->phy = devm_phy_optional_get(dev, "pcie-phy"); + if (IS_ERR(pcie->phy)) + return PTR_ERR(pcie->phy); + + platform_set_drvdata(pdev, pcie); + + ret = uniphier_pcie_host_enable(pcie); + if (ret) + return ret; + + pcie->pci.pp.ops = &uniphier_pcie_host_ops; + + return dw_pcie_host_init(&pcie->pci.pp); +} + +static const struct of_device_id uniphier_pcie_match[] = { + { .compatible = "socionext,uniphier-pcie", }, + { /* sentinel */ }, +}; + +static struct platform_driver uniphier_pcie_driver = { + .probe = uniphier_pcie_probe, + .driver = { + .name = "uniphier-pcie", + .of_match_table = uniphier_pcie_match, + }, +}; +builtin_platform_driver(uniphier_pcie_driver); |