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path: root/drivers/pci/controller/dwc/pcie-artpec6.c
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Diffstat (limited to 'drivers/pci/controller/dwc/pcie-artpec6.c')
-rw-r--r--drivers/pci/controller/dwc/pcie-artpec6.c500
1 files changed, 500 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 0000000000..9b572a2b2c
--- /dev/null
+++ b/drivers/pci/controller/dwc/pcie-artpec6.c
@@ -0,0 +1,500 @@
+// 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.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 dw_pcie_rp *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 dw_pcie_rp *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);
+
+ return 0;
+}
+
+static const struct dw_pcie_host_ops artpec6_pcie_host_ops = {
+ .host_init = artpec6_pcie_host_init,
+};
+
+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_pcie_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct dw_pcie *pci;
+ struct artpec6_pcie *artpec6_pcie;
+ int ret;
+ const struct artpec_pcie_of_data *data;
+ enum artpec_pcie_variants variant;
+ enum dw_pcie_device_mode mode;
+ u32 val;
+
+ data = of_device_get_match_data(dev);
+ if (!data)
+ return -EINVAL;
+
+ 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;
+
+ 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;
+
+ pci->pp.ops = &artpec6_pcie_host_ops;
+
+ ret = dw_pcie_host_init(&pci->pp);
+ if (ret < 0)
+ return ret;
+ break;
+ case DW_PCIE_EP_TYPE:
+ 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);
+
+ pci->ep.ops = &pcie_ep_ops;
+
+ return dw_pcie_ep_init(&pci->ep);
+ 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);