PCI: spear: Add PCIe driver for ST Microelectronics SPEAr13xx
ARM based ST Microelectronics's SPEAr1310 and SPEAr1340 SOCs have onchip
designware PCIe controller. To make that usable, this patch adds a wrapper
driver based on existing designware driver.
Adds bindings for this new driver and update MAINTAINERS as well.
Cc: linux-pci@vger.kernel.org
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Pratyush Anand <pratyush.anand@st.com>
Signed-off-by: Mohit Kumar <mohit.kumar@st.com>
[viresh: fixed logs/cclist/checkpatch warnings, broken into smaller patches]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
diff --git a/drivers/pci/host/pcie-spear13xx.c b/drivers/pci/host/pcie-spear13xx.c
new file mode 100644
index 0000000..99738e4
--- /dev/null
+++ b/drivers/pci/host/pcie-spear13xx.c
@@ -0,0 +1,405 @@
+/*
+ * 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@st.com>
+ * Mohit Kumar <mohit.kumar@st.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.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 {
+ void __iomem *app_base;
+ struct phy *phy;
+ struct clk *clk;
+ struct pcie_port pp;
+ 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 RX_LANE_FLIP_EN_ID 0
+#define TX_LANE_FLIP_EN_ID 1
+#define SYS_AUX_PWR_DET_ID 2
+#define APP_LTSSM_ENABLE_ID 3
+#define SYS_ATTEN_BUTTON_PRESSED_ID 4
+#define SYS_MRL_SENSOR_STATE_ID 5
+#define SYS_PWR_FAULT_DET_ID 6
+#define SYS_MRL_SENSOR_CHGED_ID 7
+#define SYS_PRE_DET_CHGED_ID 8
+#define SYS_CMD_CPLED_INT_ID 9
+#define APP_INIT_RST_0_ID 11
+#define APP_REQ_ENTR_L1_ID 12
+#define APP_READY_ENTR_L23_ID 13
+#define APP_REQ_EXIT_L1_ID 14
+#define DEVICE_TYPE_EP (0 << 25)
+#define DEVICE_TYPE_LEP (1 << 25)
+#define DEVICE_TYPE_RC (4 << 25)
+#define SYS_INT_ID 29
+#define MISCTRL_EN_ID 30
+#define REG_TRANSLATION_ENABLE 31
+
+/* CR1 ID */
+#define APPS_PM_XMT_TURNOFF_ID 2
+#define APPS_PM_XMT_PME_ID 5
+
+/* CR3 ID */
+#define XMLH_LTSSM_STATE_DETECT_QUIET 0x00
+#define XMLH_LTSSM_STATE_DETECT_ACT 0x01
+#define XMLH_LTSSM_STATE_POLL_ACTIVE 0x02
+#define XMLH_LTSSM_STATE_POLL_COMPLIANCE 0x03
+#define XMLH_LTSSM_STATE_POLL_CONFIG 0x04
+#define XMLH_LTSSM_STATE_PRE_DETECT_QUIET 0x05
+#define XMLH_LTSSM_STATE_DETECT_WAIT 0x06
+#define XMLH_LTSSM_STATE_CFG_LINKWD_START 0x07
+#define XMLH_LTSSM_STATE_CFG_LINKWD_ACEPT 0x08
+#define XMLH_LTSSM_STATE_CFG_LANENUM_WAIT 0x09
+#define XMLH_LTSSM_STATE_CFG_LANENUM_ACEPT 0x0A
+#define XMLH_LTSSM_STATE_CFG_COMPLETE 0x0B
+#define XMLH_LTSSM_STATE_CFG_IDLE 0x0C
+#define XMLH_LTSSM_STATE_RCVRY_LOCK 0x0D
+#define XMLH_LTSSM_STATE_RCVRY_SPEED 0x0E
+#define XMLH_LTSSM_STATE_RCVRY_RCVRCFG 0x0F
+#define XMLH_LTSSM_STATE_RCVRY_IDLE 0x10
+#define XMLH_LTSSM_STATE_L0 0x11
+#define XMLH_LTSSM_STATE_L0S 0x12
+#define XMLH_LTSSM_STATE_L123_SEND_EIDLE 0x13
+#define XMLH_LTSSM_STATE_L1_IDLE 0x14
+#define XMLH_LTSSM_STATE_L2_IDLE 0x15
+#define XMLH_LTSSM_STATE_L2_WAKE 0x16
+#define XMLH_LTSSM_STATE_DISABLED_ENTRY 0x17
+#define XMLH_LTSSM_STATE_DISABLED_IDLE 0x18
+#define XMLH_LTSSM_STATE_DISABLED 0x19
+#define XMLH_LTSSM_STATE_LPBK_ENTRY 0x1A
+#define XMLH_LTSSM_STATE_LPBK_ACTIVE 0x1B
+#define XMLH_LTSSM_STATE_LPBK_EXIT 0x1C
+#define XMLH_LTSSM_STATE_LPBK_EXIT_TIMEOUT 0x1D
+#define XMLH_LTSSM_STATE_HOT_RESET_ENTRY 0x1E
+#define XMLH_LTSSM_STATE_HOT_RESET 0x1F
+#define XMLH_LTSSM_STATE_MASK 0x3F
+#define XMLH_LINK_UP (1 << 6)
+
+/* CR4 ID */
+#define CFG_MSI_EN_ID 18
+
+/* CR6 */
+#define INTA_CTRL_INT (1 << 7)
+#define INTB_CTRL_INT (1 << 8)
+#define INTC_CTRL_INT (1 << 9)
+#define INTD_CTRL_INT (1 << 10)
+#define MSI_CTRL_INT (1 << 26)
+
+/* CR19 ID */
+#define VEN_MSI_REQ_ID 11
+#define VEN_MSI_FUN_NUM_ID 8
+#define VEN_MSI_TC_ID 5
+#define VEN_MSI_VECTOR_ID 0
+#define VEN_MSI_REQ_EN ((u32)0x1 << VEN_MSI_REQ_ID)
+#define VEN_MSI_FUN_NUM_MASK ((u32)0x7 << VEN_MSI_FUN_NUM_ID)
+#define VEN_MSI_TC_MASK ((u32)0x7 << VEN_MSI_TC_ID)
+#define VEN_MSI_VECTOR_MASK ((u32)0x1F << VEN_MSI_VECTOR_ID)
+
+#define EXP_CAP_ID_OFFSET 0x70
+
+#define to_spear13xx_pcie(x) container_of(x, struct spear13xx_pcie, pp)
+
+static int spear13xx_pcie_establish_link(struct pcie_port *pp)
+{
+ u32 val;
+ int count = 0;
+ struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
+ struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+ u32 exp_cap_off = EXP_CAP_ID_OFFSET;
+
+ if (dw_pcie_link_up(pp)) {
+ dev_err(pp->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_cfg_read(pp->dbi_base, exp_cap_off + PCI_EXP_DEVCTL, 4, &val);
+ val &= ~PCI_EXP_DEVCTL_READRQ;
+ dw_pcie_cfg_write(pp->dbi_base, exp_cap_off + PCI_EXP_DEVCTL, 4, val);
+
+ dw_pcie_cfg_write(pp->dbi_base, PCI_VENDOR_ID, 2, 0x104A);
+ dw_pcie_cfg_write(pp->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_cfg_read(pp->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_cfg_write(pp->dbi_base, exp_cap_off +
+ PCI_EXP_LNKCAP, 4, val);
+ }
+
+ dw_pcie_cfg_read(pp->dbi_base, exp_cap_off + PCI_EXP_LNKCTL2, 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_cfg_write(pp->dbi_base, exp_cap_off +
+ PCI_EXP_LNKCTL2, 4, 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);
+
+ /* check if the link is up or not */
+ while (!dw_pcie_link_up(pp)) {
+ mdelay(100);
+ count++;
+ if (count == 10) {
+ dev_err(pp->dev, "link Fail\n");
+ return -EINVAL;
+ }
+ }
+ dev_info(pp->dev, "link up\n");
+
+ return 0;
+}
+
+static irqreturn_t spear13xx_pcie_irq_handler(int irq, void *arg)
+{
+ struct pcie_port *pp = arg;
+ struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
+ struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+ unsigned int status;
+
+ status = readl(&app_reg->int_sts);
+
+ if (status & MSI_CTRL_INT) {
+ if (!IS_ENABLED(CONFIG_PCI_MSI))
+ BUG();
+ dw_handle_msi_irq(pp);
+ }
+
+ writel(status, &app_reg->int_clr);
+
+ return IRQ_HANDLED;
+}
+
+static void spear13xx_pcie_enable_interrupts(struct pcie_port *pp)
+{
+ struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(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 pcie_port *pp)
+{
+ struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
+ 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 void spear13xx_pcie_host_init(struct pcie_port *pp)
+{
+ spear13xx_pcie_establish_link(pp);
+ spear13xx_pcie_enable_interrupts(pp);
+}
+
+static struct pcie_host_ops spear13xx_pcie_host_ops = {
+ .link_up = spear13xx_pcie_link_up,
+ .host_init = spear13xx_pcie_host_init,
+};
+
+static int add_pcie_port(struct pcie_port *pp, struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ pp->irq = platform_get_irq(pdev, 0);
+ if (!pp->irq) {
+ dev_err(dev, "failed to get irq\n");
+ return -ENODEV;
+ }
+ ret = devm_request_irq(dev, pp->irq, spear13xx_pcie_irq_handler,
+ IRQF_SHARED, "spear1340-pcie", pp);
+ if (ret) {
+ dev_err(dev, "failed to request irq %d\n", pp->irq);
+ return ret;
+ }
+
+ pp->root_bus_nr = -1;
+ 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 int __init spear13xx_pcie_probe(struct platform_device *pdev)
+{
+ struct spear13xx_pcie *spear13xx_pcie;
+ struct pcie_port *pp;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = pdev->dev.of_node;
+ struct resource *dbi_base;
+ int ret;
+
+ spear13xx_pcie = devm_kzalloc(dev, sizeof(*spear13xx_pcie), GFP_KERNEL);
+ if (!spear13xx_pcie) {
+ dev_err(dev, "no memory for SPEAr13xx pcie\n");
+ return -ENOMEM;
+ }
+
+ 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;
+ }
+
+ pp = &spear13xx_pcie->pp;
+
+ pp->dev = dev;
+
+ dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ pp->dbi_base = devm_ioremap_resource(dev, dbi_base);
+ if (IS_ERR(pp->dbi_base)) {
+ dev_err(dev, "couldn't remap dbi base %p\n", dbi_base);
+ ret = PTR_ERR(pp->dbi_base);
+ goto fail_clk;
+ }
+ spear13xx_pcie->app_base = pp->dbi_base + 0x2000;
+
+ if (of_property_read_bool(np, "st,pcie-is-gen1"))
+ spear13xx_pcie->is_gen1 = true;
+
+ ret = add_pcie_port(pp, pdev);
+ if (ret < 0)
+ goto fail_clk;
+
+ platform_set_drvdata(pdev, spear13xx_pcie);
+ return 0;
+
+fail_clk:
+ clk_disable_unprepare(spear13xx_pcie->clk);
+
+ return ret;
+}
+
+static int __exit spear13xx_pcie_remove(struct platform_device *pdev)
+{
+ struct spear13xx_pcie *spear13xx_pcie = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(spear13xx_pcie->clk);
+
+ phy_exit(spear13xx_pcie->phy);
+
+ return 0;
+}
+
+static const struct of_device_id spear13xx_pcie_of_match[] = {
+ { .compatible = "st,spear1340-pcie", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, spear13xx_pcie_of_match);
+
+static struct platform_driver spear13xx_pcie_driver = {
+ .probe = spear13xx_pcie_probe,
+ .remove = spear13xx_pcie_remove,
+ .driver = {
+ .name = "spear-pcie",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(spear13xx_pcie_of_match),
+ },
+};
+
+/* SPEAr13xx PCIe driver does not allow module unload */
+
+static int __init pcie_init(void)
+{
+ return platform_driver_register(&spear13xx_pcie_driver);
+}
+module_init(pcie_init);
+
+MODULE_DESCRIPTION("ST Microelectronics SPEAr13xx PCIe host controller driver");
+MODULE_AUTHOR("Pratyush Anand <pratyush.anand@st.com>");
+MODULE_LICENSE("GPL v2");