--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCIe host bridge driver for Apple system-on-chips.
+ *
+ * The HW is ECAM compliant, so once the controller is initialized,
+ * the driver mostly deals MSI mapping and handling of per-port
+ * interrupts (INTx, management and error signals).
+ *
+ * Initialization requires enabling power and clocks, along with a
+ * number of register pokes.
+ *
+ * Copyright (C) 2021 Alyssa Rosenzweig <alyssa@rosenzweig.io>
+ * Copyright (C) 2021 Google LLC
+ * Copyright (C) 2021 Corellium LLC
+ * Copyright (C) 2021 Mark Kettenis <kettenis@openbsd.org>
+ *
+ * Author: Alyssa Rosenzweig <alyssa@rosenzweig.io>
+ * Author: Marc Zyngier <maz@kernel.org>
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/kernel.h>
+#include <linux/iopoll.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_irq.h>
+#include <linux/pci-ecam.h>
+
+#define CORE_RC_PHYIF_CTL 0x00024
+#define CORE_RC_PHYIF_CTL_RUN BIT(0)
+#define CORE_RC_PHYIF_STAT 0x00028
+#define CORE_RC_PHYIF_STAT_REFCLK BIT(4)
+#define CORE_RC_CTL 0x00050
+#define CORE_RC_CTL_RUN BIT(0)
+#define CORE_RC_STAT 0x00058
+#define CORE_RC_STAT_READY BIT(0)
+#define CORE_FABRIC_STAT 0x04000
+#define CORE_FABRIC_STAT_MASK 0x001F001F
+#define CORE_LANE_CFG(port) (0x84000 + 0x4000 * (port))
+#define CORE_LANE_CFG_REFCLK0REQ BIT(0)
+#define CORE_LANE_CFG_REFCLK1 BIT(1)
+#define CORE_LANE_CFG_REFCLK0ACK BIT(2)
+#define CORE_LANE_CFG_REFCLKEN (BIT(9) | BIT(10))
+#define CORE_LANE_CTL(port) (0x84004 + 0x4000 * (port))
+#define CORE_LANE_CTL_CFGACC BIT(15)
+
+#define PORT_LTSSMCTL 0x00080
+#define PORT_LTSSMCTL_START BIT(0)
+#define PORT_INTSTAT 0x00100
+#define PORT_INT_TUNNEL_ERR 31
+#define PORT_INT_CPL_TIMEOUT 23
+#define PORT_INT_RID2SID_MAPERR 22
+#define PORT_INT_CPL_ABORT 21
+#define PORT_INT_MSI_BAD_DATA 19
+#define PORT_INT_MSI_ERR 18
+#define PORT_INT_REQADDR_GT32 17
+#define PORT_INT_AF_TIMEOUT 15
+#define PORT_INT_LINK_DOWN 14
+#define PORT_INT_LINK_UP 12
+#define PORT_INT_LINK_BWMGMT 11
+#define PORT_INT_AER_MASK (15 << 4)
+#define PORT_INT_PORT_ERR 4
+#define PORT_INT_INTx(i) i
+#define PORT_INT_INTx_MASK 15
+#define PORT_INTMSK 0x00104
+#define PORT_INTMSKSET 0x00108
+#define PORT_INTMSKCLR 0x0010c
+#define PORT_MSICFG 0x00124
+#define PORT_MSICFG_EN BIT(0)
+#define PORT_MSICFG_L2MSINUM_SHIFT 4
+#define PORT_MSIBASE 0x00128
+#define PORT_MSIBASE_1_SHIFT 16
+#define PORT_MSIADDR 0x00168
+#define PORT_LINKSTS 0x00208
+#define PORT_LINKSTS_UP BIT(0)
+#define PORT_LINKSTS_BUSY BIT(2)
+#define PORT_LINKCMDSTS 0x00210
+#define PORT_OUTS_NPREQS 0x00284
+#define PORT_OUTS_NPREQS_REQ BIT(24)
+#define PORT_OUTS_NPREQS_CPL BIT(16)
+#define PORT_RXWR_FIFO 0x00288
+#define PORT_RXWR_FIFO_HDR GENMASK(15, 10)
+#define PORT_RXWR_FIFO_DATA GENMASK(9, 0)
+#define PORT_RXRD_FIFO 0x0028C
+#define PORT_RXRD_FIFO_REQ GENMASK(6, 0)
+#define PORT_OUTS_CPLS 0x00290
+#define PORT_OUTS_CPLS_SHRD GENMASK(14, 8)
+#define PORT_OUTS_CPLS_WAIT GENMASK(6, 0)
+#define PORT_APPCLK 0x00800
+#define PORT_APPCLK_EN BIT(0)
+#define PORT_APPCLK_CGDIS BIT(8)
+#define PORT_STATUS 0x00804
+#define PORT_STATUS_READY BIT(0)
+#define PORT_REFCLK 0x00810
+#define PORT_REFCLK_EN BIT(0)
+#define PORT_REFCLK_CGDIS BIT(8)
+#define PORT_PERST 0x00814
+#define PORT_PERST_OFF BIT(0)
+#define PORT_RID2SID(i16) (0x00828 + 4 * (i16))
+#define PORT_RID2SID_VALID BIT(31)
+#define PORT_RID2SID_SID_SHIFT 16
+#define PORT_RID2SID_BUS_SHIFT 8
+#define PORT_RID2SID_DEV_SHIFT 3
+#define PORT_RID2SID_FUNC_SHIFT 0
+#define PORT_OUTS_PREQS_HDR 0x00980
+#define PORT_OUTS_PREQS_HDR_MASK GENMASK(9, 0)
+#define PORT_OUTS_PREQS_DATA 0x00984
+#define PORT_OUTS_PREQS_DATA_MASK GENMASK(15, 0)
+#define PORT_TUNCTRL 0x00988
+#define PORT_TUNCTRL_PERST_ON BIT(0)
+#define PORT_TUNCTRL_PERST_ACK_REQ BIT(1)
+#define PORT_TUNSTAT 0x0098c
+#define PORT_TUNSTAT_PERST_ON BIT(0)
+#define PORT_TUNSTAT_PERST_ACK_PEND BIT(1)
+#define PORT_PREFMEM_ENABLE 0x00994
+
+struct apple_pcie {
+ struct device *dev;
+ void __iomem *base;
+};
+
+struct apple_pcie_port {
+ struct apple_pcie *pcie;
+ struct device_node *np;
+ void __iomem *base;
+ int idx;
+};
+
+static void rmw_set(u32 set, void __iomem *addr)
+{
+ writel_relaxed(readl_relaxed(addr) | set, addr);
+}
+
+static int apple_pcie_setup_port(struct apple_pcie *pcie,
+ struct device_node *np)
+{
+ struct platform_device *platform = to_platform_device(pcie->dev);
+ struct apple_pcie_port *port;
+ struct gpio_desc *reset;
+ u32 stat, idx;
+ int ret;
+
+ reset = gpiod_get_from_of_node(np, "reset-gpios", 0,
+ GPIOD_OUT_LOW, "#PERST");
+ if (IS_ERR(reset))
+ return PTR_ERR(reset);
+
+ port = devm_kzalloc(pcie->dev, sizeof(*port), GFP_KERNEL);
+ if (!port)
+ return -ENOMEM;
+
+ ret = of_property_read_u32_index(np, "reg", 0, &idx);
+ if (ret)
+ return ret;
+
+ /* Use the first reg entry to work out the port index */
+ port->idx = idx >> 11;
+ port->pcie = pcie;
+ port->np = np;
+
+ port->base = devm_platform_ioremap_resource(platform, port->idx + 2);
+ if (IS_ERR(port->base))
+ return PTR_ERR(port->base);
+
+ rmw_set(PORT_APPCLK_EN, port->base + PORT_APPCLK);
+
+ rmw_set(PORT_PERST_OFF, port->base + PORT_PERST);
+ gpiod_set_value(reset, 1);
+
+ ret = readl_relaxed_poll_timeout(port->base + PORT_STATUS, stat,
+ stat & PORT_STATUS_READY, 100, 250000);
+ if (ret < 0) {
+ dev_err(pcie->dev, "port %pOF ready wait timeout\n", np);
+ return ret;
+ }
+
+ writel_relaxed(PORT_LTSSMCTL_START, port->base + PORT_LTSSMCTL);
+
+ return 0;
+}
+
+static int apple_pcie_init(struct pci_config_window *cfg)
+{
+ struct device *dev = cfg->parent;
+ struct platform_device *platform = to_platform_device(dev);
+ struct device_node *of_port;
+ struct apple_pcie *pcie;
+ int ret;
+
+ pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
+ if (!pcie)
+ return -ENOMEM;
+
+ pcie->dev = dev;
+
+ pcie->base = devm_platform_ioremap_resource(platform, 1);
+ if (IS_ERR(pcie->base))
+ return PTR_ERR(pcie->base);
+
+ for_each_child_of_node(dev->of_node, of_port) {
+ ret = apple_pcie_setup_port(pcie, of_port);
+ if (ret) {
+ dev_err(pcie->dev, "Port %pOF setup fail: %d\n", of_port, ret);
+ of_node_put(of_port);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static const struct pci_ecam_ops apple_pcie_cfg_ecam_ops = {
+ .init = apple_pcie_init,
+ .pci_ops = {
+ .map_bus = pci_ecam_map_bus,
+ .read = pci_generic_config_read,
+ .write = pci_generic_config_write,
+ }
+};
+
+static const struct of_device_id apple_pcie_of_match[] = {
+ { .compatible = "apple,pcie", .data = &apple_pcie_cfg_ecam_ops },
+ { }
+};
+MODULE_DEVICE_TABLE(of, apple_pcie_of_match);
+
+static struct platform_driver apple_pcie_driver = {
+ .probe = pci_host_common_probe,
+ .driver = {
+ .name = "pcie-apple",
+ .of_match_table = apple_pcie_of_match,
+ .suppress_bind_attrs = true,
+ },
+};
+module_platform_driver(apple_pcie_driver);
+
+MODULE_LICENSE("GPL v2");
projects / platform / kernel / linux-rpi.git / commitdiff