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path: root/drivers/pci/controller/dwc/pcie-spear13xx.c
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Diffstat (limited to 'drivers/pci/controller/dwc/pcie-spear13xx.c')
-rw-r--r--drivers/pci/controller/dwc/pcie-spear13xx.c266
1 files changed, 266 insertions, 0 deletions
diff --git a/drivers/pci/controller/dwc/pcie-spear13xx.c b/drivers/pci/controller/dwc/pcie-spear13xx.c
new file mode 100644
index 000000000..99d47ae80
--- /dev/null
+++ b/drivers/pci/controller/dwc/pcie-spear13xx.c
@@ -0,0 +1,266 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCIe host controller driver for ST Microelectronics SPEAr13xx SoCs
+ *
+ * SPEAr13xx PCIe Glue Layer Source Code
+ *
+ * Copyright (C) 2010-2014 ST Microelectronics
+ * Pratyush Anand <pratyush.anand@gmail.com>
+ * Mohit Kumar <mohit.kumar.dhaka@gmail.com>
+ */
+
+#include <linux/clk.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 "pcie-designware.h"
+
+struct spear13xx_pcie {
+ struct dw_pcie *pci;
+ void __iomem *app_base;
+ struct phy *phy;
+ struct clk *clk;
+};
+
+struct pcie_app_reg {
+ u32 app_ctrl_0; /* cr0 */
+ u32 app_ctrl_1; /* cr1 */
+ u32 app_status_0; /* cr2 */
+ u32 app_status_1; /* cr3 */
+ u32 msg_status; /* cr4 */
+ u32 msg_payload; /* cr5 */
+ u32 int_sts; /* cr6 */
+ u32 int_clr; /* cr7 */
+ u32 int_mask; /* cr8 */
+ u32 mst_bmisc; /* cr9 */
+ u32 phy_ctrl; /* cr10 */
+ u32 phy_status; /* cr11 */
+ u32 cxpl_debug_info_0; /* cr12 */
+ u32 cxpl_debug_info_1; /* cr13 */
+ u32 ven_msg_ctrl_0; /* cr14 */
+ u32 ven_msg_ctrl_1; /* cr15 */
+ u32 ven_msg_data_0; /* cr16 */
+ u32 ven_msg_data_1; /* cr17 */
+ u32 ven_msi_0; /* cr18 */
+ u32 ven_msi_1; /* cr19 */
+ u32 mst_rmisc; /* cr20 */
+};
+
+/* CR0 ID */
+#define APP_LTSSM_ENABLE_ID 3
+#define DEVICE_TYPE_RC (4 << 25)
+#define MISCTRL_EN_ID 30
+#define REG_TRANSLATION_ENABLE 31
+
+/* CR3 ID */
+#define XMLH_LINK_UP (1 << 6)
+
+/* CR6 */
+#define MSI_CTRL_INT (1 << 26)
+
+#define to_spear13xx_pcie(x) dev_get_drvdata((x)->dev)
+
+static int spear13xx_pcie_start_link(struct dw_pcie *pci)
+{
+ struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pci);
+ struct pcie_app_reg __iomem *app_reg = spear13xx_pcie->app_base;
+
+ /* enable ltssm */
+ writel(DEVICE_TYPE_RC | (1 << MISCTRL_EN_ID)
+ | (1 << APP_LTSSM_ENABLE_ID)
+ | ((u32)1 << REG_TRANSLATION_ENABLE),
+ &app_reg->app_ctrl_0);
+
+ return 0;
+}
+
+static irqreturn_t spear13xx_pcie_irq_handler(int irq, void *arg)
+{
+ struct spear13xx_pcie *spear13xx_pcie = arg;
+ struct pcie_app_reg __iomem *app_reg = spear13xx_pcie->app_base;
+ struct dw_pcie *pci = spear13xx_pcie->pci;
+ struct dw_pcie_rp *pp = &pci->pp;
+ unsigned int status;
+
+ status = readl(&app_reg->int_sts);
+
+ if (status & MSI_CTRL_INT) {
+ BUG_ON(!IS_ENABLED(CONFIG_PCI_MSI));
+ dw_handle_msi_irq(pp);
+ }
+
+ writel(status, &app_reg->int_clr);
+
+ return IRQ_HANDLED;
+}
+
+static void spear13xx_pcie_enable_interrupts(struct spear13xx_pcie *spear13xx_pcie)
+{
+ struct pcie_app_reg __iomem *app_reg = spear13xx_pcie->app_base;
+
+ /* Enable MSI interrupt */
+ if (IS_ENABLED(CONFIG_PCI_MSI))
+ writel(readl(&app_reg->int_mask) |
+ MSI_CTRL_INT, &app_reg->int_mask);
+}
+
+static int spear13xx_pcie_link_up(struct dw_pcie *pci)
+{
+ struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pci);
+ struct pcie_app_reg __iomem *app_reg = spear13xx_pcie->app_base;
+
+ if (readl(&app_reg->app_status_1) & XMLH_LINK_UP)
+ return 1;
+
+ return 0;
+}
+
+static int spear13xx_pcie_host_init(struct dw_pcie_rp *pp)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+ struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pci);
+ u32 exp_cap_off = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+ u32 val;
+
+ spear13xx_pcie->app_base = pci->dbi_base + 0x2000;
+
+ /*
+ * this controller support only 128 bytes read size, however its
+ * default value in capability register is 512 bytes. So force
+ * it to 128 here.
+ */
+ val = dw_pcie_readw_dbi(pci, exp_cap_off + PCI_EXP_DEVCTL);
+ val &= ~PCI_EXP_DEVCTL_READRQ;
+ dw_pcie_writew_dbi(pci, exp_cap_off + PCI_EXP_DEVCTL, val);
+
+ dw_pcie_writew_dbi(pci, PCI_VENDOR_ID, 0x104A);
+ dw_pcie_writew_dbi(pci, PCI_DEVICE_ID, 0xCD80);
+
+ spear13xx_pcie_enable_interrupts(spear13xx_pcie);
+
+ return 0;
+}
+
+static const struct dw_pcie_host_ops spear13xx_pcie_host_ops = {
+ .host_init = spear13xx_pcie_host_init,
+};
+
+static int spear13xx_add_pcie_port(struct spear13xx_pcie *spear13xx_pcie,
+ struct platform_device *pdev)
+{
+ struct dw_pcie *pci = spear13xx_pcie->pci;
+ struct dw_pcie_rp *pp = &pci->pp;
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ pp->irq = platform_get_irq(pdev, 0);
+ if (pp->irq < 0)
+ return pp->irq;
+
+ ret = devm_request_irq(dev, pp->irq, spear13xx_pcie_irq_handler,
+ IRQF_SHARED | IRQF_NO_THREAD,
+ "spear1340-pcie", spear13xx_pcie);
+ if (ret) {
+ dev_err(dev, "failed to request irq %d\n", pp->irq);
+ return ret;
+ }
+
+ pp->ops = &spear13xx_pcie_host_ops;
+ pp->msi_irq[0] = -ENODEV;
+
+ ret = dw_pcie_host_init(pp);
+ if (ret) {
+ dev_err(dev, "failed to initialize host\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct dw_pcie_ops dw_pcie_ops = {
+ .link_up = spear13xx_pcie_link_up,
+ .start_link = spear13xx_pcie_start_link,
+};
+
+static int spear13xx_pcie_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct dw_pcie *pci;
+ struct spear13xx_pcie *spear13xx_pcie;
+ struct device_node *np = dev->of_node;
+ int ret;
+
+ spear13xx_pcie = devm_kzalloc(dev, sizeof(*spear13xx_pcie), GFP_KERNEL);
+ if (!spear13xx_pcie)
+ return -ENOMEM;
+
+ pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
+ if (!pci)
+ return -ENOMEM;
+
+ pci->dev = dev;
+ pci->ops = &dw_pcie_ops;
+
+ spear13xx_pcie->pci = pci;
+
+ spear13xx_pcie->phy = devm_phy_get(dev, "pcie-phy");
+ if (IS_ERR(spear13xx_pcie->phy)) {
+ ret = PTR_ERR(spear13xx_pcie->phy);
+ if (ret == -EPROBE_DEFER)
+ dev_info(dev, "probe deferred\n");
+ else
+ dev_err(dev, "couldn't get pcie-phy\n");
+ return ret;
+ }
+
+ phy_init(spear13xx_pcie->phy);
+
+ spear13xx_pcie->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(spear13xx_pcie->clk)) {
+ dev_err(dev, "couldn't get clk for pcie\n");
+ return PTR_ERR(spear13xx_pcie->clk);
+ }
+ ret = clk_prepare_enable(spear13xx_pcie->clk);
+ if (ret) {
+ dev_err(dev, "couldn't enable clk for pcie\n");
+ return ret;
+ }
+
+ if (of_property_read_bool(np, "st,pcie-is-gen1"))
+ pci->link_gen = 1;
+
+ platform_set_drvdata(pdev, spear13xx_pcie);
+
+ ret = spear13xx_add_pcie_port(spear13xx_pcie, pdev);
+ if (ret < 0)
+ goto fail_clk;
+
+ return 0;
+
+fail_clk:
+ clk_disable_unprepare(spear13xx_pcie->clk);
+
+ return ret;
+}
+
+static const struct of_device_id spear13xx_pcie_of_match[] = {
+ { .compatible = "st,spear1340-pcie", },
+ {},
+};
+
+static struct platform_driver spear13xx_pcie_driver = {
+ .probe = spear13xx_pcie_probe,
+ .driver = {
+ .name = "spear-pcie",
+ .of_match_table = spear13xx_pcie_of_match,
+ .suppress_bind_attrs = true,
+ },
+};
+
+builtin_platform_driver(spear13xx_pcie_driver);