PCI: spear: Add PCIe driver for ST Microelectronics SPEAr13xx
authorPratyush Anand <pratyush.anand@st.com>
Tue, 11 Feb 2014 06:09:26 +0000 (11:39 +0530)
committerViresh Kumar <viresh.kumar@linaro.org>
Mon, 14 Jul 2014 05:00:39 +0000 (10:30 +0530)
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>
Documentation/devicetree/bindings/pci/spear13xx-pcie.txt [new file with mode: 0644]
MAINTAINERS
drivers/pci/host/Kconfig
drivers/pci/host/Makefile
drivers/pci/host/pcie-spear13xx.c [new file with mode: 0644]

diff --git a/Documentation/devicetree/bindings/pci/spear13xx-pcie.txt b/Documentation/devicetree/bindings/pci/spear13xx-pcie.txt
new file mode 100644 (file)
index 0000000..49ea76d
--- /dev/null
@@ -0,0 +1,14 @@
+SPEAr13XX PCIe DT detail:
+================================
+
+SPEAr13XX uses synopsis designware PCIe controller and ST MiPHY as phy
+controller.
+
+Required properties:
+- compatible : should be "st,spear1340-pcie", "snps,dw-pcie".
+- phys             : phandle to phy node associated with pcie controller
+- phy-names        : must be "pcie-phy"
+- All other definitions as per generic PCI bindings
+
+ Optional properties:
+- st,pcie-is-gen1 indicates that forced gen1 initialization is needed.
index 702ca10..766948e 100644 (file)
@@ -6820,6 +6820,12 @@ S:       Maintained
 F:     Documentation/devicetree/bindings/pci/host-generic-pci.txt
 F:     drivers/pci/host/pci-host-generic.c
 
+PCIE DRIVER FOR ST SPEAR13XX
+M:     Mohit Kumar <mohit.kumar@st.com>
+L:     linux-pci@vger.kernel.org
+S:     Maintained
+F:     drivers/pci/host/*spear*
+
 PCMCIA SUBSYSTEM
 P:     Linux PCMCIA Team
 L:     linux-pcmcia@lists.infradead.org
index 21df477..2d8a4d0 100644 (file)
@@ -46,4 +46,12 @@ config PCI_HOST_GENERIC
          Say Y here if you want to support a simple generic PCI host
          controller, such as the one emulated by kvmtool.
 
+config PCIE_SPEAR13XX
+       tristate "STMicroelectronics SPEAr PCIe controller"
+       depends on ARCH_SPEAR13XX
+       select PCIEPORTBUS
+       select PCIE_DW
+       help
+         Say Y here if you want PCIe support on SPEAr13XX SoCs.
+
 endmenu
index 611ba4b..0daec79 100644 (file)
@@ -6,3 +6,4 @@ obj-$(CONFIG_PCI_TEGRA) += pci-tegra.o
 obj-$(CONFIG_PCI_RCAR_GEN2) += pci-rcar-gen2.o
 obj-$(CONFIG_PCI_RCAR_GEN2_PCIE) += pcie-rcar.o
 obj-$(CONFIG_PCI_HOST_GENERIC) += pci-host-generic.o
+obj-$(CONFIG_PCIE_SPEAR13XX) += pcie-spear13xx.o
diff --git a/drivers/pci/host/pcie-spear13xx.c b/drivers/pci/host/pcie-spear13xx.c
new file mode 100644 (file)
index 0000000..99738e4
--- /dev/null
@@ -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");