From: Niklas Cassel Date: Mon, 9 May 2016 11:49:03 +0000 (+0200) Subject: PCI: artpec: Add Axis ARTPEC-6 PCIe controller driver X-Git-Tag: v4.14-rc1~2732^2~3^2~14^2~1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a3cbfae1f7b3b5b3bdac23f2feea16a3bd571d1f;p=platform%2Fkernel%2Flinux-rpi.git PCI: artpec: Add Axis ARTPEC-6 PCIe controller driver The Axis ARTPEC-6 SoC integrates a PCIe controller from Synopsys. Add a new driver that provides the small glue needed to use the existing DesignWare driver to make it work on the Axis ARTPEC-6 SoC. [bhelgaas: return errors directly without gotos, fold in section mismatch fix] Signed-off-by: Niklas Cassel Signed-off-by: Bjorn Helgaas --- diff --git a/MAINTAINERS b/MAINTAINERS index ed42cb6..d26687f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -8823,6 +8823,15 @@ S: Maintained F: Documentation/devicetree/bindings/pci/xgene-pci-msi.txt F: drivers/pci/host/pci-xgene-msi.c +PCIE DRIVER FOR AXIS ARTPEC +M: Niklas Cassel +M: Jesper Nilsson +L: linux-arm-kernel@axis.com +L: linux-pci@vger.kernel.org +S: Maintained +F: Documentation/devicetree/bindings/pci/axis,artpec* +F: drivers/pci/host/*artpec* + PCIE DRIVER FOR HISILICON M: Zhou Wang M: Gabriele Paoloni diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig index 5d2374e..033d9ad 100644 --- a/drivers/pci/host/Kconfig +++ b/drivers/pci/host/Kconfig @@ -245,4 +245,13 @@ config PCIE_ARMADA_8K Designware hardware and therefore the driver re-uses the Designware core functions to implement the driver. +config PCIE_ARTPEC6 + bool "Axis ARTPEC-6 PCIe controller" + depends on MACH_ARTPEC6 + select PCIE_DW + select PCIEPORTBUS + help + Say Y here to enable PCIe controller support on Axis ARTPEC-6 + SoCs. This PCIe controller uses the DesignWare core. + endmenu diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile index 9c8698e..5bc0af2 100644 --- a/drivers/pci/host/Makefile +++ b/drivers/pci/host/Makefile @@ -29,3 +29,4 @@ obj-$(CONFIG_PCIE_QCOM) += pcie-qcom.o obj-$(CONFIG_PCI_HOST_THUNDER_ECAM) += pci-thunder-ecam.o obj-$(CONFIG_PCI_HOST_THUNDER_PEM) += pci-thunder-pem.o obj-$(CONFIG_PCIE_ARMADA_8K) += pcie-armada8k.o +obj-$(CONFIG_PCIE_ARTPEC6) += pcie-artpec6.o diff --git a/drivers/pci/host/pcie-artpec6.c b/drivers/pci/host/pcie-artpec6.c new file mode 100644 index 0000000..be54fad --- /dev/null +++ b/drivers/pci/host/pcie-artpec6.c @@ -0,0 +1,284 @@ +/* + * PCIe host controller driver for Axis ARTPEC-6 SoC + * + * Based on work done by Phil Edworthy + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "pcie-designware.h" + +#define to_artpec6_pcie(x) container_of(x, struct artpec6_pcie, pp) + +struct artpec6_pcie { + struct pcie_port pp; + struct regmap *regmap; + void __iomem *phy_base; +}; + +/* PCIe Port Logic registers (memory-mapped) */ +#define PL_OFFSET 0x700 +#define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28) +#define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c) + +#define MISC_CONTROL_1_OFF (PL_OFFSET + 0x1bc) +#define DBI_RO_WR_EN 1 + +/* ARTPEC-6 specific registers */ +#define PCIECFG 0x18 +#define PCIECFG_DBG_OEN (1 << 24) +#define PCIECFG_CORE_RESET_REQ (1 << 21) +#define PCIECFG_LTSSM_ENABLE (1 << 20) +#define PCIECFG_CLKREQ_B (1 << 11) +#define PCIECFG_REFCLK_ENABLE (1 << 10) +#define PCIECFG_PLL_ENABLE (1 << 9) +#define PCIECFG_PCLK_ENABLE (1 << 8) +#define PCIECFG_RISRCREN (1 << 4) +#define PCIECFG_MODE_TX_DRV_EN (1 << 3) +#define PCIECFG_CISRREN (1 << 2) +#define PCIECFG_MACRO_ENABLE (1 << 0) + +#define NOCCFG 0x40 +#define NOCCFG_ENABLE_CLK_PCIE (1 << 4) +#define NOCCFG_POWER_PCIE_IDLEACK (1 << 3) +#define NOCCFG_POWER_PCIE_IDLE (1 << 2) +#define NOCCFG_POWER_PCIE_IDLEREQ (1 << 1) + +#define PHY_STATUS 0x118 +#define PHY_COSPLLLOCK (1 << 0) + +#define ARTPEC6_CPU_TO_BUS_ADDR 0x0fffffff + +static int artpec6_pcie_establish_link(struct pcie_port *pp) +{ + struct artpec6_pcie *artpec6_pcie = to_artpec6_pcie(pp); + u32 val; + unsigned int retries; + + /* Hold DW core in reset */ + regmap_read(artpec6_pcie->regmap, PCIECFG, &val); + val |= PCIECFG_CORE_RESET_REQ; + regmap_write(artpec6_pcie->regmap, PCIECFG, val); + + regmap_read(artpec6_pcie->regmap, PCIECFG, &val); + val |= PCIECFG_RISRCREN | /* Receiver term. 50 Ohm */ + PCIECFG_MODE_TX_DRV_EN | + PCIECFG_CISRREN | /* Reference clock term. 100 Ohm */ + PCIECFG_MACRO_ENABLE; + val |= PCIECFG_REFCLK_ENABLE; + val &= ~PCIECFG_DBG_OEN; + val &= ~PCIECFG_CLKREQ_B; + regmap_write(artpec6_pcie->regmap, PCIECFG, val); + usleep_range(5000, 6000); + + regmap_read(artpec6_pcie->regmap, NOCCFG, &val); + val |= NOCCFG_ENABLE_CLK_PCIE; + regmap_write(artpec6_pcie->regmap, NOCCFG, val); + usleep_range(20, 30); + + regmap_read(artpec6_pcie->regmap, PCIECFG, &val); + val |= PCIECFG_PCLK_ENABLE | PCIECFG_PLL_ENABLE; + regmap_write(artpec6_pcie->regmap, PCIECFG, val); + usleep_range(6000, 7000); + + regmap_read(artpec6_pcie->regmap, NOCCFG, &val); + val &= ~NOCCFG_POWER_PCIE_IDLEREQ; + regmap_write(artpec6_pcie->regmap, NOCCFG, val); + + retries = 50; + do { + usleep_range(1000, 2000); + regmap_read(artpec6_pcie->regmap, NOCCFG, &val); + retries--; + } while (retries && + (val & (NOCCFG_POWER_PCIE_IDLEACK | NOCCFG_POWER_PCIE_IDLE))); + + retries = 50; + do { + usleep_range(1000, 2000); + val = readl(artpec6_pcie->phy_base + PHY_STATUS); + retries--; + } while (retries && !(val & PHY_COSPLLLOCK)); + + /* Take DW core out of reset */ + regmap_read(artpec6_pcie->regmap, PCIECFG, &val); + val &= ~PCIECFG_CORE_RESET_REQ; + regmap_write(artpec6_pcie->regmap, PCIECFG, val); + usleep_range(100, 200); + + /* + * Enable writing to config regs. This is required as the Synopsys + * driver changes the class code. That register needs DBI write enable. + */ + writel(DBI_RO_WR_EN, pp->dbi_base + MISC_CONTROL_1_OFF); + + pp->io_base &= ARTPEC6_CPU_TO_BUS_ADDR; + pp->mem_base &= ARTPEC6_CPU_TO_BUS_ADDR; + pp->cfg0_base &= ARTPEC6_CPU_TO_BUS_ADDR; + pp->cfg1_base &= ARTPEC6_CPU_TO_BUS_ADDR; + + /* setup root complex */ + dw_pcie_setup_rc(pp); + + /* assert LTSSM enable */ + regmap_read(artpec6_pcie->regmap, PCIECFG, &val); + val |= PCIECFG_LTSSM_ENABLE; + regmap_write(artpec6_pcie->regmap, PCIECFG, val); + + /* check if the link is up or not */ + if (!dw_pcie_wait_for_link(pp)) + return 0; + + dev_dbg(pp->dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n", + readl(pp->dbi_base + PCIE_PHY_DEBUG_R0), + readl(pp->dbi_base + PCIE_PHY_DEBUG_R1)); + + return -ETIMEDOUT; +} + +static void artpec6_pcie_enable_interrupts(struct pcie_port *pp) +{ + if (IS_ENABLED(CONFIG_PCI_MSI)) + dw_pcie_msi_init(pp); +} + +static void artpec6_pcie_host_init(struct pcie_port *pp) +{ + artpec6_pcie_establish_link(pp); + artpec6_pcie_enable_interrupts(pp); +} + +static int artpec6_pcie_link_up(struct pcie_port *pp) +{ + u32 rc; + + /* + * Get status from Synopsys IP + * link is debug bit 36, debug register 1 starts at bit 32 + */ + rc = readl(pp->dbi_base + PCIE_PHY_DEBUG_R1) & (0x1 << (36 - 32)); + if (rc) + return 1; + + return 0; +} + +static struct pcie_host_ops artpec6_pcie_host_ops = { + .link_up = artpec6_pcie_link_up, + .host_init = artpec6_pcie_host_init, +}; + +static irqreturn_t artpec6_pcie_msi_handler(int irq, void *arg) +{ + struct pcie_port *pp = arg; + + return dw_handle_msi_irq(pp); +} + +static int __init artpec6_add_pcie_port(struct pcie_port *pp, + struct platform_device *pdev) +{ + int ret; + + if (IS_ENABLED(CONFIG_PCI_MSI)) { + pp->msi_irq = platform_get_irq_byname(pdev, "msi"); + if (pp->msi_irq <= 0) { + dev_err(&pdev->dev, "failed to get MSI irq\n"); + return -ENODEV; + } + + ret = devm_request_irq(&pdev->dev, pp->msi_irq, + artpec6_pcie_msi_handler, + IRQF_SHARED | IRQF_NO_THREAD, + "artpec6-pcie-msi", pp); + if (ret) { + dev_err(&pdev->dev, "failed to request MSI irq\n"); + return ret; + } + } + + pp->root_bus_nr = -1; + pp->ops = &artpec6_pcie_host_ops; + + ret = dw_pcie_host_init(pp); + if (ret) { + dev_err(&pdev->dev, "failed to initialize host\n"); + return ret; + } + + return 0; +} + +static int artpec6_pcie_probe(struct platform_device *pdev) +{ + struct artpec6_pcie *artpec6_pcie; + struct pcie_port *pp; + struct resource *dbi_base; + struct resource *phy_base; + int ret; + + artpec6_pcie = devm_kzalloc(&pdev->dev, sizeof(*artpec6_pcie), + GFP_KERNEL); + if (!artpec6_pcie) + return -ENOMEM; + + pp = &artpec6_pcie->pp; + pp->dev = &pdev->dev; + + dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi"); + pp->dbi_base = devm_ioremap_resource(&pdev->dev, dbi_base); + if (IS_ERR(pp->dbi_base)) + return PTR_ERR(pp->dbi_base); + + phy_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "phy"); + artpec6_pcie->phy_base = devm_ioremap_resource(&pdev->dev, phy_base); + if (IS_ERR(artpec6_pcie->phy_base)) + return PTR_ERR(artpec6_pcie->phy_base); + + artpec6_pcie->regmap = + syscon_regmap_lookup_by_phandle(pdev->dev.of_node, + "axis,syscon-pcie"); + if (IS_ERR(artpec6_pcie->regmap)) + return PTR_ERR(artpec6_pcie->regmap); + + ret = artpec6_add_pcie_port(pp, pdev); + if (ret < 0) + return ret; + + platform_set_drvdata(pdev, artpec6_pcie); + return 0; +} + +static const struct of_device_id artpec6_pcie_of_match[] = { + { .compatible = "axis,artpec6-pcie", }, + {}, +}; +MODULE_DEVICE_TABLE(of, artpec6_pcie_of_match); + +static struct platform_driver artpec6_pcie_driver = { + .probe = artpec6_pcie_probe, + .driver = { + .name = "artpec6-pcie", + .of_match_table = artpec6_pcie_of_match, + }, +}; + +module_platform_driver(artpec6_pcie_driver); + +MODULE_AUTHOR("Niklas Cassel "); +MODULE_DESCRIPTION("Axis ARTPEC-6 PCIe host controller driver"); +MODULE_LICENSE("GPL v2");