summaryrefslogtreecommitdiffstats
path: root/drivers/pci/controller/dwc/pcie-spear13xx.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/pci/controller/dwc/pcie-spear13xx.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pci/controller/dwc/pcie-spear13xx.c')
-rw-r--r--drivers/pci/controller/dwc/pcie-spear13xx.c313
1 files changed, 313 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..7d0cdfd81
--- /dev/null
+++ b/drivers/pci/controller/dwc/pcie-spear13xx.c
@@ -0,0 +1,313 @@
+// 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;
+ bool is_gen1;
+};
+
+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 EXP_CAP_ID_OFFSET 0x70
+
+#define to_spear13xx_pcie(x) dev_get_drvdata((x)->dev)
+
+static int spear13xx_pcie_establish_link(struct spear13xx_pcie *spear13xx_pcie)
+{
+ struct dw_pcie *pci = spear13xx_pcie->pci;
+ struct pcie_port *pp = &pci->pp;
+ struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+ u32 val;
+ u32 exp_cap_off = EXP_CAP_ID_OFFSET;
+
+ if (dw_pcie_link_up(pci)) {
+ dev_err(pci->dev, "link already up\n");
+ return 0;
+ }
+
+ dw_pcie_setup_rc(pp);
+
+ /*
+ * this controller support only 128 bytes read size, however its
+ * default value in capability register is 512 bytes. So force
+ * it to 128 here.
+ */
+ dw_pcie_read(pci->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, &val);
+ val &= ~PCI_EXP_DEVCTL_READRQ;
+ dw_pcie_write(pci->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, val);
+
+ dw_pcie_write(pci->dbi_base + PCI_VENDOR_ID, 2, 0x104A);
+ dw_pcie_write(pci->dbi_base + PCI_DEVICE_ID, 2, 0xCD80);
+
+ /*
+ * if is_gen1 is set then handle it, so that some buggy card
+ * also works
+ */
+ if (spear13xx_pcie->is_gen1) {
+ dw_pcie_read(pci->dbi_base + exp_cap_off + PCI_EXP_LNKCAP,
+ 4, &val);
+ if ((val & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_2_5GB) {
+ val &= ~((u32)PCI_EXP_LNKCAP_SLS);
+ val |= PCI_EXP_LNKCAP_SLS_2_5GB;
+ dw_pcie_write(pci->dbi_base + exp_cap_off +
+ PCI_EXP_LNKCAP, 4, val);
+ }
+
+ dw_pcie_read(pci->dbi_base + exp_cap_off + PCI_EXP_LNKCTL2,
+ 2, &val);
+ if ((val & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_2_5GB) {
+ val &= ~((u32)PCI_EXP_LNKCAP_SLS);
+ val |= PCI_EXP_LNKCAP_SLS_2_5GB;
+ dw_pcie_write(pci->dbi_base + exp_cap_off +
+ PCI_EXP_LNKCTL2, 2, val);
+ }
+ }
+
+ /* 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 dw_pcie_wait_for_link(pci);
+}
+
+static irqreturn_t spear13xx_pcie_irq_handler(int irq, void *arg)
+{
+ struct spear13xx_pcie *spear13xx_pcie = arg;
+ struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+ struct dw_pcie *pci = spear13xx_pcie->pci;
+ struct pcie_port *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 dw_pcie *pci = spear13xx_pcie->pci;
+ struct pcie_port *pp = &pci->pp;
+ struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+
+ /* Enable MSI interrupt */
+ if (IS_ENABLED(CONFIG_PCI_MSI)) {
+ dw_pcie_msi_init(pp);
+ 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 *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 pcie_port *pp)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+ struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pci);
+
+ spear13xx_pcie_establish_link(spear13xx_pcie);
+ 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 pcie_port *pp = &pci->pp;
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ pp->irq = platform_get_irq(pdev, 0);
+ if (pp->irq < 0) {
+ dev_err(dev, "failed to get irq\n");
+ 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;
+
+ 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,
+};
+
+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;
+ struct resource *dbi_base;
+ 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;
+ }
+
+ dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
+ pci->dbi_base = devm_pci_remap_cfg_resource(dev, dbi_base);
+ if (IS_ERR(pci->dbi_base)) {
+ dev_err(dev, "couldn't remap dbi base %p\n", dbi_base);
+ ret = PTR_ERR(pci->dbi_base);
+ goto fail_clk;
+ }
+ spear13xx_pcie->app_base = pci->dbi_base + 0x2000;
+
+ if (of_property_read_bool(np, "st,pcie-is-gen1"))
+ spear13xx_pcie->is_gen1 = true;
+
+ 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 = of_match_ptr(spear13xx_pcie_of_match),
+ .suppress_bind_attrs = true,
+ },
+};
+
+builtin_platform_driver(spear13xx_pcie_driver);