diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-artpec6.c | 567 |
1 files changed, 567 insertions, 0 deletions
diff --git a/drivers/pci/controller/dwc/pcie-artpec6.c b/drivers/pci/controller/dwc/pcie-artpec6.c new file mode 100644 index 000000000..929448e9e --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-artpec6.c @@ -0,0 +1,567 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCIe host controller driver for Axis ARTPEC-6 SoC + * + * Author: Niklas Cassel <niklas.cassel@axis.com> + * + * Based on work done by Phil Edworthy <phil@edworthys.org> + */ + +#include <linux/delay.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/of_device.h> +#include <linux/pci.h> +#include <linux/platform_device.h> +#include <linux/resource.h> +#include <linux/signal.h> +#include <linux/types.h> +#include <linux/interrupt.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.h> + +#include "pcie-designware.h" + +#define to_artpec6_pcie(x) dev_get_drvdata((x)->dev) + +enum artpec_pcie_variants { + ARTPEC6, + ARTPEC7, +}; + +struct artpec6_pcie { + struct dw_pcie *pci; + struct regmap *regmap; /* DT axis,syscon-pcie */ + void __iomem *phy_base; /* DT phy */ + enum artpec_pcie_variants variant; + enum dw_pcie_device_mode mode; +}; + +struct artpec_pcie_of_data { + enum artpec_pcie_variants variant; + enum dw_pcie_device_mode mode; +}; + +static const struct of_device_id artpec6_pcie_of_match[]; + +/* ARTPEC-6 specific registers */ +#define PCIECFG 0x18 +#define PCIECFG_DBG_OEN BIT(24) +#define PCIECFG_CORE_RESET_REQ BIT(21) +#define PCIECFG_LTSSM_ENABLE BIT(20) +#define PCIECFG_DEVICE_TYPE_MASK GENMASK(19, 16) +#define PCIECFG_CLKREQ_B BIT(11) +#define PCIECFG_REFCLK_ENABLE BIT(10) +#define PCIECFG_PLL_ENABLE BIT(9) +#define PCIECFG_PCLK_ENABLE BIT(8) +#define PCIECFG_RISRCREN BIT(4) +#define PCIECFG_MODE_TX_DRV_EN BIT(3) +#define PCIECFG_CISRREN BIT(2) +#define PCIECFG_MACRO_ENABLE BIT(0) +/* ARTPEC-7 specific fields */ +#define PCIECFG_REFCLKSEL BIT(23) +#define PCIECFG_NOC_RESET BIT(3) + +#define PCIESTAT 0x1c +/* ARTPEC-7 specific fields */ +#define PCIESTAT_EXTREFCLK BIT(3) + +#define NOCCFG 0x40 +#define NOCCFG_ENABLE_CLK_PCIE BIT(4) +#define NOCCFG_POWER_PCIE_IDLEACK BIT(3) +#define NOCCFG_POWER_PCIE_IDLE BIT(2) +#define NOCCFG_POWER_PCIE_IDLEREQ BIT(1) + +#define PHY_STATUS 0x118 +#define PHY_COSPLLLOCK BIT(0) + +#define PHY_TX_ASIC_OUT 0x4040 +#define PHY_TX_ASIC_OUT_TX_ACK BIT(0) + +#define PHY_RX_ASIC_OUT 0x405c +#define PHY_RX_ASIC_OUT_ACK BIT(0) + +static u32 artpec6_pcie_readl(struct artpec6_pcie *artpec6_pcie, u32 offset) +{ + u32 val; + + regmap_read(artpec6_pcie->regmap, offset, &val); + return val; +} + +static void artpec6_pcie_writel(struct artpec6_pcie *artpec6_pcie, u32 offset, u32 val) +{ + regmap_write(artpec6_pcie->regmap, offset, val); +} + +static u64 artpec6_pcie_cpu_addr_fixup(struct dw_pcie *pci, u64 pci_addr) +{ + struct artpec6_pcie *artpec6_pcie = to_artpec6_pcie(pci); + struct pcie_port *pp = &pci->pp; + struct dw_pcie_ep *ep = &pci->ep; + + switch (artpec6_pcie->mode) { + case DW_PCIE_RC_TYPE: + return pci_addr - pp->cfg0_base; + case DW_PCIE_EP_TYPE: + return pci_addr - ep->phys_base; + default: + dev_err(pci->dev, "UNKNOWN device type\n"); + } + return pci_addr; +} + +static int artpec6_pcie_establish_link(struct dw_pcie *pci) +{ + struct artpec6_pcie *artpec6_pcie = to_artpec6_pcie(pci); + u32 val; + + val = artpec6_pcie_readl(artpec6_pcie, PCIECFG); + val |= PCIECFG_LTSSM_ENABLE; + artpec6_pcie_writel(artpec6_pcie, PCIECFG, val); + + return 0; +} + +static void artpec6_pcie_stop_link(struct dw_pcie *pci) +{ + struct artpec6_pcie *artpec6_pcie = to_artpec6_pcie(pci); + u32 val; + + val = artpec6_pcie_readl(artpec6_pcie, PCIECFG); + val &= ~PCIECFG_LTSSM_ENABLE; + artpec6_pcie_writel(artpec6_pcie, PCIECFG, val); +} + +static const struct dw_pcie_ops dw_pcie_ops = { + .cpu_addr_fixup = artpec6_pcie_cpu_addr_fixup, + .start_link = artpec6_pcie_establish_link, + .stop_link = artpec6_pcie_stop_link, +}; + +static void artpec6_pcie_wait_for_phy_a6(struct artpec6_pcie *artpec6_pcie) +{ + struct dw_pcie *pci = artpec6_pcie->pci; + struct device *dev = pci->dev; + u32 val; + unsigned int retries; + + retries = 50; + do { + usleep_range(1000, 2000); + val = artpec6_pcie_readl(artpec6_pcie, NOCCFG); + retries--; + } while (retries && + (val & (NOCCFG_POWER_PCIE_IDLEACK | NOCCFG_POWER_PCIE_IDLE))); + if (!retries) + dev_err(dev, "PCIe clock manager did not leave idle state\n"); + + retries = 50; + do { + usleep_range(1000, 2000); + val = readl(artpec6_pcie->phy_base + PHY_STATUS); + retries--; + } while (retries && !(val & PHY_COSPLLLOCK)); + if (!retries) + dev_err(dev, "PHY PLL did not lock\n"); +} + +static void artpec6_pcie_wait_for_phy_a7(struct artpec6_pcie *artpec6_pcie) +{ + struct dw_pcie *pci = artpec6_pcie->pci; + struct device *dev = pci->dev; + u32 val; + u16 phy_status_tx, phy_status_rx; + unsigned int retries; + + retries = 50; + do { + usleep_range(1000, 2000); + val = artpec6_pcie_readl(artpec6_pcie, NOCCFG); + retries--; + } while (retries && + (val & (NOCCFG_POWER_PCIE_IDLEACK | NOCCFG_POWER_PCIE_IDLE))); + if (!retries) + dev_err(dev, "PCIe clock manager did not leave idle state\n"); + + retries = 50; + do { + usleep_range(1000, 2000); + phy_status_tx = readw(artpec6_pcie->phy_base + PHY_TX_ASIC_OUT); + phy_status_rx = readw(artpec6_pcie->phy_base + PHY_RX_ASIC_OUT); + retries--; + } while (retries && ((phy_status_tx & PHY_TX_ASIC_OUT_TX_ACK) || + (phy_status_rx & PHY_RX_ASIC_OUT_ACK))); + if (!retries) + dev_err(dev, "PHY did not enter Pn state\n"); +} + +static void artpec6_pcie_wait_for_phy(struct artpec6_pcie *artpec6_pcie) +{ + switch (artpec6_pcie->variant) { + case ARTPEC6: + artpec6_pcie_wait_for_phy_a6(artpec6_pcie); + break; + case ARTPEC7: + artpec6_pcie_wait_for_phy_a7(artpec6_pcie); + break; + } +} + +static void artpec6_pcie_init_phy_a6(struct artpec6_pcie *artpec6_pcie) +{ + u32 val; + + val = artpec6_pcie_readl(artpec6_pcie, PCIECFG); + 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; + artpec6_pcie_writel(artpec6_pcie, PCIECFG, val); + usleep_range(5000, 6000); + + val = artpec6_pcie_readl(artpec6_pcie, NOCCFG); + val |= NOCCFG_ENABLE_CLK_PCIE; + artpec6_pcie_writel(artpec6_pcie, NOCCFG, val); + usleep_range(20, 30); + + val = artpec6_pcie_readl(artpec6_pcie, PCIECFG); + val |= PCIECFG_PCLK_ENABLE | PCIECFG_PLL_ENABLE; + artpec6_pcie_writel(artpec6_pcie, PCIECFG, val); + usleep_range(6000, 7000); + + val = artpec6_pcie_readl(artpec6_pcie, NOCCFG); + val &= ~NOCCFG_POWER_PCIE_IDLEREQ; + artpec6_pcie_writel(artpec6_pcie, NOCCFG, val); +} + +static void artpec6_pcie_init_phy_a7(struct artpec6_pcie *artpec6_pcie) +{ + struct dw_pcie *pci = artpec6_pcie->pci; + u32 val; + bool extrefclk; + + /* Check if external reference clock is connected */ + val = artpec6_pcie_readl(artpec6_pcie, PCIESTAT); + extrefclk = !!(val & PCIESTAT_EXTREFCLK); + dev_dbg(pci->dev, "Using reference clock: %s\n", + extrefclk ? "external" : "internal"); + + val = artpec6_pcie_readl(artpec6_pcie, PCIECFG); + val |= PCIECFG_RISRCREN | /* Receiver term. 50 Ohm */ + PCIECFG_PCLK_ENABLE; + if (extrefclk) + val |= PCIECFG_REFCLKSEL; + else + val &= ~PCIECFG_REFCLKSEL; + artpec6_pcie_writel(artpec6_pcie, PCIECFG, val); + usleep_range(10, 20); + + val = artpec6_pcie_readl(artpec6_pcie, NOCCFG); + val |= NOCCFG_ENABLE_CLK_PCIE; + artpec6_pcie_writel(artpec6_pcie, NOCCFG, val); + usleep_range(20, 30); + + val = artpec6_pcie_readl(artpec6_pcie, NOCCFG); + val &= ~NOCCFG_POWER_PCIE_IDLEREQ; + artpec6_pcie_writel(artpec6_pcie, NOCCFG, val); +} + +static void artpec6_pcie_init_phy(struct artpec6_pcie *artpec6_pcie) +{ + switch (artpec6_pcie->variant) { + case ARTPEC6: + artpec6_pcie_init_phy_a6(artpec6_pcie); + break; + case ARTPEC7: + artpec6_pcie_init_phy_a7(artpec6_pcie); + break; + } +} + +static void artpec6_pcie_assert_core_reset(struct artpec6_pcie *artpec6_pcie) +{ + u32 val; + + val = artpec6_pcie_readl(artpec6_pcie, PCIECFG); + switch (artpec6_pcie->variant) { + case ARTPEC6: + val |= PCIECFG_CORE_RESET_REQ; + break; + case ARTPEC7: + val &= ~PCIECFG_NOC_RESET; + break; + } + artpec6_pcie_writel(artpec6_pcie, PCIECFG, val); +} + +static void artpec6_pcie_deassert_core_reset(struct artpec6_pcie *artpec6_pcie) +{ + u32 val; + + val = artpec6_pcie_readl(artpec6_pcie, PCIECFG); + switch (artpec6_pcie->variant) { + case ARTPEC6: + val &= ~PCIECFG_CORE_RESET_REQ; + break; + case ARTPEC7: + val |= PCIECFG_NOC_RESET; + break; + } + artpec6_pcie_writel(artpec6_pcie, PCIECFG, val); + usleep_range(100, 200); +} + +static int artpec6_pcie_host_init(struct pcie_port *pp) +{ + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct artpec6_pcie *artpec6_pcie = to_artpec6_pcie(pci); + + if (artpec6_pcie->variant == ARTPEC7) { + pci->n_fts[0] = 180; + pci->n_fts[1] = 180; + } + artpec6_pcie_assert_core_reset(artpec6_pcie); + artpec6_pcie_init_phy(artpec6_pcie); + artpec6_pcie_deassert_core_reset(artpec6_pcie); + artpec6_pcie_wait_for_phy(artpec6_pcie); + dw_pcie_setup_rc(pp); + artpec6_pcie_establish_link(pci); + dw_pcie_wait_for_link(pci); + dw_pcie_msi_init(pp); + + return 0; +} + +static const struct dw_pcie_host_ops artpec6_pcie_host_ops = { + .host_init = artpec6_pcie_host_init, +}; + +static int artpec6_add_pcie_port(struct artpec6_pcie *artpec6_pcie, + struct platform_device *pdev) +{ + struct dw_pcie *pci = artpec6_pcie->pci; + struct pcie_port *pp = &pci->pp; + struct device *dev = pci->dev; + int ret; + + if (IS_ENABLED(CONFIG_PCI_MSI)) { + pp->msi_irq = platform_get_irq_byname(pdev, "msi"); + if (pp->msi_irq < 0) + return pp->msi_irq; + } + + pp->ops = &artpec6_pcie_host_ops; + + ret = dw_pcie_host_init(pp); + if (ret) { + dev_err(dev, "failed to initialize host\n"); + return ret; + } + + return 0; +} + +static void artpec6_pcie_ep_init(struct dw_pcie_ep *ep) +{ + struct dw_pcie *pci = to_dw_pcie_from_ep(ep); + struct artpec6_pcie *artpec6_pcie = to_artpec6_pcie(pci); + enum pci_barno bar; + + artpec6_pcie_assert_core_reset(artpec6_pcie); + artpec6_pcie_init_phy(artpec6_pcie); + artpec6_pcie_deassert_core_reset(artpec6_pcie); + artpec6_pcie_wait_for_phy(artpec6_pcie); + + for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) + dw_pcie_ep_reset_bar(pci, bar); +} + +static int artpec6_pcie_raise_irq(struct dw_pcie_ep *ep, u8 func_no, + enum pci_epc_irq_type type, u16 interrupt_num) +{ + struct dw_pcie *pci = to_dw_pcie_from_ep(ep); + + switch (type) { + case PCI_EPC_IRQ_LEGACY: + dev_err(pci->dev, "EP cannot trigger legacy IRQs\n"); + return -EINVAL; + case PCI_EPC_IRQ_MSI: + return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num); + default: + dev_err(pci->dev, "UNKNOWN IRQ type\n"); + } + + return 0; +} + +static const struct dw_pcie_ep_ops pcie_ep_ops = { + .ep_init = artpec6_pcie_ep_init, + .raise_irq = artpec6_pcie_raise_irq, +}; + +static int artpec6_add_pcie_ep(struct artpec6_pcie *artpec6_pcie, + struct platform_device *pdev) +{ + int ret; + struct dw_pcie_ep *ep; + struct resource *res; + struct device *dev = &pdev->dev; + struct dw_pcie *pci = artpec6_pcie->pci; + + ep = &pci->ep; + ep->ops = &pcie_ep_ops; + + pci->dbi_base2 = devm_platform_ioremap_resource_byname(pdev, "dbi2"); + if (IS_ERR(pci->dbi_base2)) + return PTR_ERR(pci->dbi_base2); + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "addr_space"); + if (!res) + return -EINVAL; + + ep->phys_base = res->start; + ep->addr_size = resource_size(res); + + ret = dw_pcie_ep_init(ep); + if (ret) { + dev_err(dev, "failed to initialize endpoint\n"); + return ret; + } + + return 0; +} + +static int artpec6_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct dw_pcie *pci; + struct artpec6_pcie *artpec6_pcie; + int ret; + const struct of_device_id *match; + const struct artpec_pcie_of_data *data; + enum artpec_pcie_variants variant; + enum dw_pcie_device_mode mode; + + match = of_match_device(artpec6_pcie_of_match, dev); + if (!match) + return -EINVAL; + + data = (struct artpec_pcie_of_data *)match->data; + variant = (enum artpec_pcie_variants)data->variant; + mode = (enum dw_pcie_device_mode)data->mode; + + artpec6_pcie = devm_kzalloc(dev, sizeof(*artpec6_pcie), GFP_KERNEL); + if (!artpec6_pcie) + return -ENOMEM; + + pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL); + if (!pci) + return -ENOMEM; + + pci->dev = dev; + pci->ops = &dw_pcie_ops; + + artpec6_pcie->pci = pci; + artpec6_pcie->variant = variant; + artpec6_pcie->mode = mode; + + pci->dbi_base = devm_platform_ioremap_resource_byname(pdev, "dbi"); + if (IS_ERR(pci->dbi_base)) + return PTR_ERR(pci->dbi_base); + + artpec6_pcie->phy_base = + devm_platform_ioremap_resource_byname(pdev, "phy"); + if (IS_ERR(artpec6_pcie->phy_base)) + return PTR_ERR(artpec6_pcie->phy_base); + + artpec6_pcie->regmap = + syscon_regmap_lookup_by_phandle(dev->of_node, + "axis,syscon-pcie"); + if (IS_ERR(artpec6_pcie->regmap)) + return PTR_ERR(artpec6_pcie->regmap); + + platform_set_drvdata(pdev, artpec6_pcie); + + switch (artpec6_pcie->mode) { + case DW_PCIE_RC_TYPE: + if (!IS_ENABLED(CONFIG_PCIE_ARTPEC6_HOST)) + return -ENODEV; + + ret = artpec6_add_pcie_port(artpec6_pcie, pdev); + if (ret < 0) + return ret; + break; + case DW_PCIE_EP_TYPE: { + u32 val; + + if (!IS_ENABLED(CONFIG_PCIE_ARTPEC6_EP)) + return -ENODEV; + + val = artpec6_pcie_readl(artpec6_pcie, PCIECFG); + val &= ~PCIECFG_DEVICE_TYPE_MASK; + artpec6_pcie_writel(artpec6_pcie, PCIECFG, val); + ret = artpec6_add_pcie_ep(artpec6_pcie, pdev); + if (ret < 0) + return ret; + break; + } + default: + dev_err(dev, "INVALID device type %d\n", artpec6_pcie->mode); + } + + return 0; +} + +static const struct artpec_pcie_of_data artpec6_pcie_rc_of_data = { + .variant = ARTPEC6, + .mode = DW_PCIE_RC_TYPE, +}; + +static const struct artpec_pcie_of_data artpec6_pcie_ep_of_data = { + .variant = ARTPEC6, + .mode = DW_PCIE_EP_TYPE, +}; + +static const struct artpec_pcie_of_data artpec7_pcie_rc_of_data = { + .variant = ARTPEC7, + .mode = DW_PCIE_RC_TYPE, +}; + +static const struct artpec_pcie_of_data artpec7_pcie_ep_of_data = { + .variant = ARTPEC7, + .mode = DW_PCIE_EP_TYPE, +}; + +static const struct of_device_id artpec6_pcie_of_match[] = { + { + .compatible = "axis,artpec6-pcie", + .data = &artpec6_pcie_rc_of_data, + }, + { + .compatible = "axis,artpec6-pcie-ep", + .data = &artpec6_pcie_ep_of_data, + }, + { + .compatible = "axis,artpec7-pcie", + .data = &artpec7_pcie_rc_of_data, + }, + { + .compatible = "axis,artpec7-pcie-ep", + .data = &artpec7_pcie_ep_of_data, + }, + {}, +}; + +static struct platform_driver artpec6_pcie_driver = { + .probe = artpec6_pcie_probe, + .driver = { + .name = "artpec6-pcie", + .of_match_table = artpec6_pcie_of_match, + .suppress_bind_attrs = true, + }, +}; +builtin_platform_driver(artpec6_pcie_driver); |