[PATCH 5/7] pci: Add Apple PCIe controller driver
Mark Kettenis
kettenis at openbsd.org
Tue Jan 17 23:04:02 CET 2023
This driver supports the PCIe controller on the Apple M1 and
M2 SoCs. The code is adapted from the Linux driver.
Signed-off-by: Mark Kettenis <kettenis at openbsd.org>
---
MAINTAINERS | 1 +
arch/arm/Kconfig | 2 +
drivers/pci/Kconfig | 9 +
drivers/pci/Makefile | 1 +
drivers/pci/pcie_apple.c | 354 +++++++++++++++++++++++++++++++++++++++
5 files changed, 367 insertions(+)
create mode 100644 drivers/pci/pcie_apple.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 3fc4cd0f12..b8a947f9d3 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -122,6 +122,7 @@ F: arch/arm/mach-apple/
F: configs/apple_m1_defconfig
F: drivers/iommu/apple_dart.c
F: drivers/nvme/nvme_apple.c
+F: drivers/pci/pcie_apple.c
F: drivers/pinctrl/pinctrl-apple.c
F: drivers/watchdog/apple_wdt.c
F: include/configs/apple.h
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index cac4fa09fd..780815269b 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -963,6 +963,7 @@ config ARCH_APPLE
bool "Apple SoCs"
select ARM64
select CLK
+ select CMD_PCI
select CMD_USB
select DM
select DM_GPIO
@@ -977,6 +978,7 @@ config ARCH_APPLE
select LINUX_KERNEL_IMAGE_HEADER
select OF_BOARD_SETUP
select OF_CONTROL
+ select PCI
select PINCTRL
select POSITION_INDEPENDENT
select POWER_DOMAIN
diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index 22f4995453..d61596cd7c 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -105,6 +105,15 @@ config PCIE_ECAM_SYNQUACER
Note that this must be configured when boot because Linux driver
expects the PCIe RC has been configured in the bootloader.
+config PCIE_APPLE
+ bool "Enable Apple PCIe driver"
+ depends on ARCH_APPLE
+ imply PCI_INIT_R
+ default y
+ help
+ Say Y here if you want to enable PCIe controller support on
+ Apple SoCs.
+
config PCI_GT64120
bool "GT64120 PCI support"
depends on MIPS
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index dd1ad91ced..d393f1ba03 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_PCI) += pci_auto_common.o pci_common.o
obj-$(CONFIG_PCIE_ECAM_GENERIC) += pcie_ecam_generic.o
obj-$(CONFIG_PCIE_ECAM_SYNQUACER) += pcie_ecam_synquacer.o
+obj-$(CONFIG_PCIE_APPLE) += pcie_apple.o
obj-$(CONFIG_PCI_GT64120) += pci_gt64120.o
obj-$(CONFIG_PCI_MPC85XX) += pci_mpc85xx.o
obj-$(CONFIG_PCI_MSC01) += pci_msc01.o
diff --git a/drivers/pci/pcie_apple.c b/drivers/pci/pcie_apple.c
new file mode 100644
index 0000000000..9b08e1e5da
--- /dev/null
+++ b/drivers/pci/pcie_apple.c
@@ -0,0 +1,354 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCIe host bridge driver for Apple system-on-chips.
+ *
+ * The HW is ECAM compliant.
+ *
+ * Initialization requires enabling power and clocks, along with a
+ * number of register pokes.
+ *
+ * Copyright (C) 2021 Alyssa Rosenzweig <alyssa at rosenzweig.io>
+ * Copyright (C) 2021 Google LLC
+ * Copyright (C) 2021 Corellium LLC
+ * Copyright (C) 2021 Mark Kettenis <kettenis at openbsd.org>
+ *
+ * Author: Alyssa Rosenzweig <alyssa at rosenzweig.io>
+ * Author: Marc Zyngier <maz at kernel.org>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/device_compat.h>
+#include <dm/devres.h>
+#include <mapmem.h>
+#include <pci.h>
+#include <asm/io.h>
+#include <asm-generic/gpio.h>
+#include <linux/delay.h>
+#include <linux/iopoll.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_REFCLK1REQ BIT(1)
+#define CORE_LANE_CFG_REFCLK0ACK BIT(2)
+#define CORE_LANE_CFG_REFCLK1ACK BIT(3)
+#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_priv {
+ struct udevice *dev;
+ void __iomem *base;
+ void __iomem *cfg_base;
+ struct list_head ports;
+};
+
+struct apple_pcie_port {
+ struct apple_pcie_priv *pcie;
+ struct gpio_desc reset;
+ ofnode np;
+ void __iomem *base;
+ struct list_head entry;
+ int idx;
+};
+
+static void rmw_set(u32 set, void __iomem *addr)
+{
+ writel_relaxed(readl_relaxed(addr) | set, addr);
+}
+
+static void rmw_clear(u32 clr, void __iomem *addr)
+{
+ writel_relaxed(readl_relaxed(addr) & ~clr, addr);
+}
+
+static int apple_pcie_config_address(const struct udevice *bus,
+ pci_dev_t bdf, uint offset,
+ void **paddress)
+{
+ struct apple_pcie_priv *pcie = dev_get_priv(bus);
+ void *addr;
+
+ addr = pcie->cfg_base;
+ addr += PCIE_ECAM_OFFSET(PCI_BUS(bdf), PCI_DEV(bdf),
+ PCI_FUNC(bdf), offset);
+ *paddress = addr;
+
+ return 0;
+}
+
+static int apple_pcie_read_config(const struct udevice *bus, pci_dev_t bdf,
+ uint offset, ulong *valuep,
+ enum pci_size_t size)
+{
+ int ret;
+
+ ret = pci_generic_mmap_read_config(bus, apple_pcie_config_address,
+ bdf, offset, valuep, size);
+ return ret;
+}
+
+static int apple_pcie_write_config(struct udevice *bus, pci_dev_t bdf,
+ uint offset, ulong value,
+ enum pci_size_t size)
+{
+ return pci_generic_mmap_write_config(bus, apple_pcie_config_address,
+ bdf, offset, value, size);
+}
+
+static const struct dm_pci_ops apple_pcie_ops = {
+ .read_config = apple_pcie_read_config,
+ .write_config = apple_pcie_write_config,
+};
+
+static int apple_pcie_setup_refclk(struct apple_pcie_priv *pcie,
+ struct apple_pcie_port *port)
+{
+ u32 stat;
+ int res;
+
+ res = readl_poll_sleep_timeout(pcie->base + CORE_RC_PHYIF_STAT, stat,
+ stat & CORE_RC_PHYIF_STAT_REFCLK,
+ 100, 50000);
+ if (res < 0)
+ return res;
+
+ rmw_set(CORE_LANE_CTL_CFGACC, pcie->base + CORE_LANE_CTL(port->idx));
+ rmw_set(CORE_LANE_CFG_REFCLK0REQ, pcie->base + CORE_LANE_CFG(port->idx));
+
+ res = readl_poll_sleep_timeout(pcie->base + CORE_LANE_CFG(port->idx),
+ stat, stat & CORE_LANE_CFG_REFCLK0ACK,
+ 100, 50000);
+ if (res < 0)
+ return res;
+
+ rmw_set(CORE_LANE_CFG_REFCLK1REQ, pcie->base + CORE_LANE_CFG(port->idx));
+ res = readl_poll_sleep_timeout(pcie->base + CORE_LANE_CFG(port->idx),
+ stat, stat & CORE_LANE_CFG_REFCLK1ACK,
+ 100, 50000);
+
+ if (res < 0)
+ return res;
+
+ rmw_clear(CORE_LANE_CTL_CFGACC, pcie->base + CORE_LANE_CTL(port->idx));
+
+ rmw_set(CORE_LANE_CFG_REFCLKEN, pcie->base + CORE_LANE_CFG(port->idx));
+ rmw_set(PORT_REFCLK_EN, port->base + PORT_REFCLK);
+
+ return 0;
+}
+
+static int apple_pcie_setup_port(struct apple_pcie_priv *pcie, ofnode np)
+{
+ struct apple_pcie_port *port;
+ struct gpio_desc reset;
+ fdt_addr_t addr;
+ u32 stat, idx;
+ int ret;
+
+ ret = gpio_request_by_name_nodev(np, "reset-gpios", 0, &reset, 0);
+ if (ret)
+ return ret;
+
+ port = devm_kzalloc(pcie->dev, sizeof(*port), GFP_KERNEL);
+ if (!port)
+ return -ENOMEM;
+
+ ret = ofnode_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->reset = reset;
+ port->np = np;
+
+ addr = dev_read_addr_index(pcie->dev, port->idx + 2);
+ if (addr == FDT_ADDR_T_NONE)
+ return -EINVAL;
+ port->base = map_sysmem(addr, 0);
+
+ rmw_set(PORT_APPCLK_EN, port->base + PORT_APPCLK);
+
+ /* Assert PERST# before setting up the clock */
+ dm_gpio_set_value(&reset, 1);
+
+ ret = apple_pcie_setup_refclk(pcie, port);
+ if (ret < 0)
+ return ret;
+
+ /* The minimal Tperst-clk value is 100us (PCIe CEM r5.0, 2.9.2) */
+ udelay(100);
+
+ /* Deassert PERST# */
+ rmw_set(PORT_PERST_OFF, port->base + PORT_PERST);
+ dm_gpio_set_value(&reset, 0);
+
+ /* Wait for 100ms after PERST# deassertion (PCIe r5.0, 6.6.1) */
+ udelay(100 * 1000);
+
+ ret = readl_poll_sleep_timeout(port->base + PORT_STATUS, stat,
+ stat & PORT_STATUS_READY, 100, 250000);
+ if (ret < 0) {
+ dev_err(pcie->dev, "port %d ready wait timeout\n", port->idx);
+ return ret;
+ }
+
+ rmw_clear(PORT_REFCLK_CGDIS, port->base + PORT_REFCLK);
+ rmw_clear(PORT_APPCLK_CGDIS, port->base + PORT_APPCLK);
+
+ list_add_tail(&port->entry, &pcie->ports);
+
+ writel_relaxed(PORT_LTSSMCTL_START, port->base + PORT_LTSSMCTL);
+
+ /*
+ * Deliberately ignore the link not coming up as connected
+ * devices (e.g. the WiFi controller) may not be powerd up.
+ */
+ readl_poll_sleep_timeout(port->base + PORT_LINKSTS, stat,
+ (stat & PORT_LINKSTS_UP), 100, 100000);
+
+ return 0;
+}
+
+static int apple_pcie_probe(struct udevice *dev)
+{
+ struct apple_pcie_priv *pcie = dev_get_priv(dev);
+ fdt_addr_t addr;
+ ofnode of_port;
+ int i, ret;
+
+ pcie->dev = dev;
+ addr = dev_read_addr_index(dev, 0);
+ if (addr == FDT_ADDR_T_NONE)
+ return -EINVAL;
+ pcie->cfg_base = map_sysmem(addr, 0);
+
+ addr = dev_read_addr_index(dev, 1);
+ if (addr == FDT_ADDR_T_NONE)
+ return -EINVAL;
+ pcie->base = map_sysmem(addr, 0);
+
+ INIT_LIST_HEAD(&pcie->ports);
+
+ for (of_port = ofnode_first_subnode(dev_ofnode(dev));
+ ofnode_valid(of_port);
+ of_port = ofnode_next_subnode(of_port)) {
+ ret = apple_pcie_setup_port(pcie, of_port);
+ if (ret) {
+ dev_err(pcie->dev, "Port %d setup fail: %d\n", i, ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int apple_pcie_remove(struct udevice *dev)
+{
+ struct apple_pcie_priv *pcie = dev_get_priv(dev);
+ struct apple_pcie_port *port, *tmp;
+
+ list_for_each_entry_safe(port, tmp, &pcie->ports, entry) {
+ gpio_free_list_nodev(&port->reset, 1);
+ free(port);
+ }
+
+ return 0;
+}
+
+static const struct udevice_id apple_pcie_of_match[] = {
+ { .compatible = "apple,pcie" },
+ { /* sentinel */ }
+};
+
+U_BOOT_DRIVER(apple_pcie) = {
+ .name = "apple_pcie",
+ .id = UCLASS_PCI,
+ .of_match = apple_pcie_of_match,
+ .probe = apple_pcie_probe,
+ .remove = apple_pcie_remove,
+ .priv_auto = sizeof(struct apple_pcie_priv),
+ .ops = &apple_pcie_ops,
+};
--
2.39.0
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