diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-armada8k.c | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/drivers/pci/controller/dwc/pcie-armada8k.c b/drivers/pci/controller/dwc/pcie-armada8k.c new file mode 100644 index 000000000..0c389a30e --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-armada8k.c @@ -0,0 +1,281 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCIe host controller driver for Marvell Armada-8K SoCs + * + * Armada-8K PCIe Glue Layer Source Code + * + * Copyright (C) 2016 Marvell Technology Group Ltd. + * + * Author: Yehuda Yitshak <yehuday@marvell.com> + * Author: Shadi Ammouri <shadi@marvell.com> + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/of.h> +#include <linux/pci.h> +#include <linux/phy/phy.h> +#include <linux/platform_device.h> +#include <linux/resource.h> +#include <linux/of_pci.h> +#include <linux/of_irq.h> + +#include "pcie-designware.h" + +struct armada8k_pcie { + struct dw_pcie *pci; + struct clk *clk; + struct clk *clk_reg; +}; + +#define PCIE_VENDOR_REGS_OFFSET 0x8000 + +#define PCIE_GLOBAL_CONTROL_REG (PCIE_VENDOR_REGS_OFFSET + 0x0) +#define PCIE_APP_LTSSM_EN BIT(2) +#define PCIE_DEVICE_TYPE_SHIFT 4 +#define PCIE_DEVICE_TYPE_MASK 0xF +#define PCIE_DEVICE_TYPE_RC 0x4 /* Root complex */ + +#define PCIE_GLOBAL_STATUS_REG (PCIE_VENDOR_REGS_OFFSET + 0x8) +#define PCIE_GLB_STS_RDLH_LINK_UP BIT(1) +#define PCIE_GLB_STS_PHY_LINK_UP BIT(9) + +#define PCIE_GLOBAL_INT_CAUSE1_REG (PCIE_VENDOR_REGS_OFFSET + 0x1C) +#define PCIE_GLOBAL_INT_MASK1_REG (PCIE_VENDOR_REGS_OFFSET + 0x20) +#define PCIE_INT_A_ASSERT_MASK BIT(9) +#define PCIE_INT_B_ASSERT_MASK BIT(10) +#define PCIE_INT_C_ASSERT_MASK BIT(11) +#define PCIE_INT_D_ASSERT_MASK BIT(12) + +#define PCIE_ARCACHE_TRC_REG (PCIE_VENDOR_REGS_OFFSET + 0x50) +#define PCIE_AWCACHE_TRC_REG (PCIE_VENDOR_REGS_OFFSET + 0x54) +#define PCIE_ARUSER_REG (PCIE_VENDOR_REGS_OFFSET + 0x5C) +#define PCIE_AWUSER_REG (PCIE_VENDOR_REGS_OFFSET + 0x60) +/* + * AR/AW Cache defauls: Normal memory, Write-Back, Read / Write + * allocate + */ +#define ARCACHE_DEFAULT_VALUE 0x3511 +#define AWCACHE_DEFAULT_VALUE 0x5311 + +#define DOMAIN_OUTER_SHAREABLE 0x2 +#define AX_USER_DOMAIN_MASK 0x3 +#define AX_USER_DOMAIN_SHIFT 4 + +#define to_armada8k_pcie(x) dev_get_drvdata((x)->dev) + +static int armada8k_pcie_link_up(struct dw_pcie *pci) +{ + u32 reg; + u32 mask = PCIE_GLB_STS_RDLH_LINK_UP | PCIE_GLB_STS_PHY_LINK_UP; + + reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_STATUS_REG); + + if ((reg & mask) == mask) + return 1; + + dev_dbg(pci->dev, "No link detected (Global-Status: 0x%08x).\n", reg); + return 0; +} + +static void armada8k_pcie_establish_link(struct armada8k_pcie *pcie) +{ + struct dw_pcie *pci = pcie->pci; + u32 reg; + + if (!dw_pcie_link_up(pci)) { + /* Disable LTSSM state machine to enable configuration */ + reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_CONTROL_REG); + reg &= ~(PCIE_APP_LTSSM_EN); + dw_pcie_writel_dbi(pci, PCIE_GLOBAL_CONTROL_REG, reg); + } + + /* Set the device to root complex mode */ + reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_CONTROL_REG); + reg &= ~(PCIE_DEVICE_TYPE_MASK << PCIE_DEVICE_TYPE_SHIFT); + reg |= PCIE_DEVICE_TYPE_RC << PCIE_DEVICE_TYPE_SHIFT; + dw_pcie_writel_dbi(pci, PCIE_GLOBAL_CONTROL_REG, reg); + + /* Set the PCIe master AxCache attributes */ + dw_pcie_writel_dbi(pci, PCIE_ARCACHE_TRC_REG, ARCACHE_DEFAULT_VALUE); + dw_pcie_writel_dbi(pci, PCIE_AWCACHE_TRC_REG, AWCACHE_DEFAULT_VALUE); + + /* Set the PCIe master AxDomain attributes */ + reg = dw_pcie_readl_dbi(pci, PCIE_ARUSER_REG); + reg &= ~(AX_USER_DOMAIN_MASK << AX_USER_DOMAIN_SHIFT); + reg |= DOMAIN_OUTER_SHAREABLE << AX_USER_DOMAIN_SHIFT; + dw_pcie_writel_dbi(pci, PCIE_ARUSER_REG, reg); + + reg = dw_pcie_readl_dbi(pci, PCIE_AWUSER_REG); + reg &= ~(AX_USER_DOMAIN_MASK << AX_USER_DOMAIN_SHIFT); + reg |= DOMAIN_OUTER_SHAREABLE << AX_USER_DOMAIN_SHIFT; + dw_pcie_writel_dbi(pci, PCIE_AWUSER_REG, reg); + + /* Enable INT A-D interrupts */ + reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_INT_MASK1_REG); + reg |= PCIE_INT_A_ASSERT_MASK | PCIE_INT_B_ASSERT_MASK | + PCIE_INT_C_ASSERT_MASK | PCIE_INT_D_ASSERT_MASK; + dw_pcie_writel_dbi(pci, PCIE_GLOBAL_INT_MASK1_REG, reg); + + if (!dw_pcie_link_up(pci)) { + /* Configuration done. Start LTSSM */ + reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_CONTROL_REG); + reg |= PCIE_APP_LTSSM_EN; + dw_pcie_writel_dbi(pci, PCIE_GLOBAL_CONTROL_REG, reg); + } + + /* Wait until the link becomes active again */ + if (dw_pcie_wait_for_link(pci)) + dev_err(pci->dev, "Link not up after reconfiguration\n"); +} + +static int armada8k_pcie_host_init(struct pcie_port *pp) +{ + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct armada8k_pcie *pcie = to_armada8k_pcie(pci); + + dw_pcie_setup_rc(pp); + armada8k_pcie_establish_link(pcie); + + return 0; +} + +static irqreturn_t armada8k_pcie_irq_handler(int irq, void *arg) +{ + struct armada8k_pcie *pcie = arg; + struct dw_pcie *pci = pcie->pci; + u32 val; + + /* + * Interrupts are directly handled by the device driver of the + * PCI device. However, they are also latched into the PCIe + * controller, so we simply discard them. + */ + val = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_INT_CAUSE1_REG); + dw_pcie_writel_dbi(pci, PCIE_GLOBAL_INT_CAUSE1_REG, val); + + return IRQ_HANDLED; +} + +static const struct dw_pcie_host_ops armada8k_pcie_host_ops = { + .host_init = armada8k_pcie_host_init, +}; + +static int armada8k_add_pcie_port(struct armada8k_pcie *pcie, + struct platform_device *pdev) +{ + struct dw_pcie *pci = pcie->pci; + struct pcie_port *pp = &pci->pp; + struct device *dev = &pdev->dev; + int ret; + + pp->ops = &armada8k_pcie_host_ops; + + pp->irq = platform_get_irq(pdev, 0); + if (pp->irq < 0) { + dev_err(dev, "failed to get irq for port\n"); + return pp->irq; + } + + ret = devm_request_irq(dev, pp->irq, armada8k_pcie_irq_handler, + IRQF_SHARED, "armada8k-pcie", pcie); + if (ret) { + dev_err(dev, "failed to request irq %d\n", pp->irq); + return ret; + } + + ret = dw_pcie_host_init(pp); + if (ret) { + dev_err(dev, "failed to initialize host: %d\n", ret); + return ret; + } + + return 0; +} + +static const struct dw_pcie_ops dw_pcie_ops = { + .link_up = armada8k_pcie_link_up, +}; + +static int armada8k_pcie_probe(struct platform_device *pdev) +{ + struct dw_pcie *pci; + struct armada8k_pcie *pcie; + struct device *dev = &pdev->dev; + struct resource *base; + int ret; + + pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL); + if (!pcie) + return -ENOMEM; + + pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL); + if (!pci) + return -ENOMEM; + + pci->dev = dev; + pci->ops = &dw_pcie_ops; + + pcie->pci = pci; + + pcie->clk = devm_clk_get(dev, NULL); + if (IS_ERR(pcie->clk)) + return PTR_ERR(pcie->clk); + + ret = clk_prepare_enable(pcie->clk); + if (ret) + return ret; + + pcie->clk_reg = devm_clk_get(dev, "reg"); + if (pcie->clk_reg == ERR_PTR(-EPROBE_DEFER)) { + ret = -EPROBE_DEFER; + goto fail; + } + if (!IS_ERR(pcie->clk_reg)) { + ret = clk_prepare_enable(pcie->clk_reg); + if (ret) + goto fail_clkreg; + } + + /* Get the dw-pcie unit configuration/control registers base. */ + base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ctrl"); + pci->dbi_base = devm_pci_remap_cfg_resource(dev, base); + if (IS_ERR(pci->dbi_base)) { + dev_err(dev, "couldn't remap regs base %p\n", base); + ret = PTR_ERR(pci->dbi_base); + goto fail_clkreg; + } + + platform_set_drvdata(pdev, pcie); + + ret = armada8k_add_pcie_port(pcie, pdev); + if (ret) + goto fail_clkreg; + + return 0; + +fail_clkreg: + clk_disable_unprepare(pcie->clk_reg); +fail: + clk_disable_unprepare(pcie->clk); + + return ret; +} + +static const struct of_device_id armada8k_pcie_of_match[] = { + { .compatible = "marvell,armada8k-pcie", }, + {}, +}; + +static struct platform_driver armada8k_pcie_driver = { + .probe = armada8k_pcie_probe, + .driver = { + .name = "armada8k-pcie", + .of_match_table = of_match_ptr(armada8k_pcie_of_match), + .suppress_bind_attrs = true, + }, +}; +builtin_platform_driver(armada8k_pcie_driver); |