From: Chen Wang <unicorn_wang@xxxxxxxxxxx> Add support for PCIe controller in SG2042 SoC. The controller uses the Cadence PCIe core programmed by pcie-cadence*.c. The PCIe controller will work in host mode only. Signed-off-by: Chen Wang <unicorn_wang@xxxxxxxxxxx> --- drivers/pci/controller/cadence/Kconfig | 11 + drivers/pci/controller/cadence/Makefile | 1 + drivers/pci/controller/cadence/pcie-sg2042.c | 611 +++++++++++++++++++ 3 files changed, 623 insertions(+) create mode 100644 drivers/pci/controller/cadence/pcie-sg2042.c diff --git a/drivers/pci/controller/cadence/Kconfig b/drivers/pci/controller/cadence/Kconfig index 8a0044bb3989..45a16215ea94 100644 --- a/drivers/pci/controller/cadence/Kconfig +++ b/drivers/pci/controller/cadence/Kconfig @@ -67,4 +67,15 @@ config PCI_J721E_EP Say Y here if you want to support the TI J721E PCIe platform controller in endpoint mode. TI J721E PCIe controller uses Cadence PCIe core. + +config PCIE_SG2042 + bool "Sophgo SG2042 PCIe controller (host mode)" + depends on ARCH_SOPHGO || COMPILE_TEST + depends on OF + select PCIE_CADENCE_HOST + help + Say Y here if you want to support the Sophgo SG2042 PCIe platform + controller in host mode. Sophgo SG2042 PCIe controller uses Cadence + PCIe core. + endmenu diff --git a/drivers/pci/controller/cadence/Makefile b/drivers/pci/controller/cadence/Makefile index 9bac5fb2f13d..89aa316f54ac 100644 --- a/drivers/pci/controller/cadence/Makefile +++ b/drivers/pci/controller/cadence/Makefile @@ -4,3 +4,4 @@ obj-$(CONFIG_PCIE_CADENCE_HOST) += pcie-cadence-host.o obj-$(CONFIG_PCIE_CADENCE_EP) += pcie-cadence-ep.o obj-$(CONFIG_PCIE_CADENCE_PLAT) += pcie-cadence-plat.o obj-$(CONFIG_PCI_J721E) += pci-j721e.o +obj-$(CONFIG_PCIE_SG2042) += pcie-sg2042.o \ No newline at end of file diff --git a/drivers/pci/controller/cadence/pcie-sg2042.c b/drivers/pci/controller/cadence/pcie-sg2042.c new file mode 100644 index 000000000000..809edb8e7259 --- /dev/null +++ b/drivers/pci/controller/cadence/pcie-sg2042.c @@ -0,0 +1,611 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * pcie-sg2042 - PCIe controller driver for Sophgo SG2042 SoC + * + * Copyright (C) 2024 Sophgo Technology Inc. + * Copyright (C) 2024 Chen Wang <unicorn_wang@xxxxxxxxxxx> + */ + +#include <linux/bits.h> +#include <linux/irq.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/irqdomain.h> +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/msi.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_pci.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/regmap.h> + +#include "pcie-cadence.h" + +/* + * SG2042 PCIe controller supports two ways to report MSI: + * - Method A, the PICe controller implements an MSI interrupt controller inside, + * and connect to PLIC upward through one interrupt line. Provides + * memory-mapped msi address, and by programming the upper 32 bits of the + * address to zero, it can be compatible with old pcie devices that only + * support 32-bit msi address. + * - Method B, the PICe controller connects to PLIC upward through an + * independent MSI controller "sophgo,sg2042-msi" on the SOC. The MSI + * controller provides multiple(up to 32) interrupt sources to PLIC. + * Compared with the first method, the advantage is that the interrupt source + * is expanded, but because for SG2042, the msi address provided by the MSI + * controller is fixed and only supports 64-bit address(> 2^32), it is not + * compatible with old pcie devices that only support 32-bit msi address. + * Method A & B can be configured in DTS with property "sophgo,internal-msi", + * default is Method B. + */ + +#define MAX_MSI_IRQS 8 +#define MAX_MSI_IRQS_PER_CTRL 1 +#define MAX_MSI_CTRLS (MAX_MSI_IRQS / MAX_MSI_IRQS_PER_CTRL) +#define MSI_DEF_NUM_VECTORS MAX_MSI_IRQS +#define BYTE_NUM_PER_MSI_VEC 4 + +#define REG_CLEAR 0x0804 +#define REG_STATUS 0x0810 +#define REG_LINK0_MSI_ADDR_SIZE 0x085C +#define REG_LINK1_MSI_ADDR_SIZE 0x080C +#define REG_LINK0_MSI_ADDR_LOW 0x0860 +#define REG_LINK0_MSI_ADDR_HIGH 0x0864 +#define REG_LINK1_MSI_ADDR_LOW 0x0868 +#define REG_LINK1_MSI_ADDR_HIGH 0x086C + +#define REG_CLEAR_LINK0_BIT 2 +#define REG_CLEAR_LINK1_BIT 3 +#define REG_STATUS_LINK0_BIT 2 +#define REG_STATUS_LINK1_BIT 3 + +#define REG_LINK0_MSI_ADDR_SIZE_MASK GENMASK(15, 0) +#define REG_LINK1_MSI_ADDR_SIZE_MASK GENMASK(31, 16) + +#define SG2042_CDNS_PLAT_CPU_TO_BUS_ADDR 0xCFFFFFFFFF + +struct sg2042_pcie { + struct cdns_pcie *cdns_pcie; + + struct regmap *syscon; + + u32 link_id; + u32 internal_msi; /* Flag if use internal MSI controller, default external */ + + struct irq_domain *msi_domain; + + int msi_irq; + + dma_addr_t msi_phys; + void *msi_virt; + + u32 num_applied_vecs; /* number of applied vectors, used to speed up ISR */ + + raw_spinlock_t lock; + DECLARE_BITMAP(msi_irq_in_use, MAX_MSI_IRQS); +}; + +static void sg2042_pcie_msi_irq_mask_external(struct irq_data *d) +{ + pci_msi_mask_irq(d); + irq_chip_mask_parent(d); +} + +static void sg2042_pcie_msi_irq_unmask_external(struct irq_data *d) +{ + pci_msi_unmask_irq(d); + irq_chip_unmask_parent(d); +} + +static struct irq_chip sg2042_pcie_msi_chip_external = { + .name = "SG2042 PCIe MSI External", + .irq_ack = irq_chip_ack_parent, + .irq_mask = sg2042_pcie_msi_irq_mask_external, + .irq_unmask = sg2042_pcie_msi_irq_unmask_external, +}; + +static struct msi_domain_info sg2042_pcie_msi_domain_info_external = { + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS), + .chip = &sg2042_pcie_msi_chip_external, +}; + +static struct irq_chip sg2042_pcie_msi_chip = { + .name = "SG2042 PCIe MSI", + .irq_ack = irq_chip_ack_parent, +}; + +static struct msi_domain_info sg2042_pcie_msi_domain_info = { + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS), + .chip = &sg2042_pcie_msi_chip, +}; + +static void sg2042_pcie_msi_clear_status(struct sg2042_pcie *pcie) +{ + u32 status, clr_msi_in_bit; + + if (pcie->link_id == 1) + clr_msi_in_bit = BIT(REG_CLEAR_LINK1_BIT); + else + clr_msi_in_bit = BIT(REG_CLEAR_LINK0_BIT); + + regmap_read(pcie->syscon, REG_CLEAR, &status); + status |= clr_msi_in_bit; + regmap_write(pcie->syscon, REG_CLEAR, status); + + /* need write 0 to reset, hardware can not reset automatically */ + status &= ~clr_msi_in_bit; + regmap_write(pcie->syscon, REG_CLEAR, status); +} + +static int sg2042_pcie_msi_irq_set_affinity(struct irq_data *d, + const struct cpumask *mask, + bool force) +{ + if (d->parent_data) + return irq_chip_set_affinity_parent(d, mask, force); + + return -EINVAL; +} + +static void sg2042_pcie_msi_irq_compose_msi_msg(struct irq_data *d, + struct msi_msg *msg) +{ + struct sg2042_pcie *pcie = irq_data_get_irq_chip_data(d); + struct device *dev = pcie->cdns_pcie->dev; + + msg->address_lo = lower_32_bits(pcie->msi_phys) + BYTE_NUM_PER_MSI_VEC * d->hwirq; + msg->address_hi = upper_32_bits(pcie->msi_phys); + msg->data = 1; + + pcie->num_applied_vecs = d->hwirq; + + dev_info(dev, "compose msi msg hwirq[%d] address_hi[%#x] address_lo[%#x]\n", + (int)d->hwirq, msg->address_hi, msg->address_lo); +} + +static void sg2042_pcie_msi_irq_ack(struct irq_data *d) +{ + struct sg2042_pcie *pcie = irq_data_get_irq_chip_data(d); + + sg2042_pcie_msi_clear_status(pcie); +} + +static struct irq_chip sg2042_pcie_msi_bottom_chip = { + .name = "SG2042 PCIe PLIC-MSI translator", + .irq_ack = sg2042_pcie_msi_irq_ack, + .irq_compose_msi_msg = sg2042_pcie_msi_irq_compose_msi_msg, +#ifdef CONFIG_SMP + .irq_set_affinity = sg2042_pcie_msi_irq_set_affinity, +#endif +}; + +static int sg2042_pcie_irq_domain_alloc(struct irq_domain *domain, + unsigned int virq, unsigned int nr_irqs, + void *args) +{ + struct sg2042_pcie *pcie = domain->host_data; + unsigned long flags; + u32 i; + int bit; + + raw_spin_lock_irqsave(&pcie->lock, flags); + + bit = bitmap_find_free_region(pcie->msi_irq_in_use, MSI_DEF_NUM_VECTORS, + order_base_2(nr_irqs)); + + raw_spin_unlock_irqrestore(&pcie->lock, flags); + + if (bit < 0) + return -ENOSPC; + + for (i = 0; i < nr_irqs; i++) + irq_domain_set_info(domain, virq + i, bit + i, + &sg2042_pcie_msi_bottom_chip, + pcie, handle_edge_irq, + NULL, NULL); + + return 0; +} + +static void sg2042_pcie_irq_domain_free(struct irq_domain *domain, + unsigned int virq, unsigned int nr_irqs) +{ + struct irq_data *d = irq_domain_get_irq_data(domain, virq); + struct sg2042_pcie *pcie = irq_data_get_irq_chip_data(d); + unsigned long flags; + + raw_spin_lock_irqsave(&pcie->lock, flags); + + bitmap_release_region(pcie->msi_irq_in_use, d->hwirq, + order_base_2(nr_irqs)); + + raw_spin_unlock_irqrestore(&pcie->lock, flags); +} + +static const struct irq_domain_ops sg2042_pcie_msi_domain_ops = { + .alloc = sg2042_pcie_irq_domain_alloc, + .free = sg2042_pcie_irq_domain_free, +}; + +/* + * We use the usual two domain structure, the top one being a generic PCI/MSI + * domain, the bottom one being SG2042-specific and handling the actual HW + * interrupt allocation. + * At the same time, for internal MSI controller(Method A), bottom chip uses a + * chained handler to handle the controller's MSI IRQ edge triggered. + */ +static int sg2042_pcie_create_msi_domain(struct sg2042_pcie *pcie, + struct irq_domain *parent) +{ + struct device *dev = pcie->cdns_pcie->dev; + struct fwnode_handle *fwnode = of_node_to_fwnode(dev->of_node); + + if (pcie->internal_msi) + pcie->msi_domain = pci_msi_create_irq_domain(fwnode, + &sg2042_pcie_msi_domain_info, + parent); + + else + pcie->msi_domain = pci_msi_create_irq_domain(fwnode, + &sg2042_pcie_msi_domain_info_external, + parent); + + if (!pcie->msi_domain) { + dev_err(dev, "Failed to create MSI domain\n"); + return -ENOMEM; + } + + return 0; +} + +static int sg2042_pcie_setup_msi_external(struct sg2042_pcie *pcie) +{ + struct device *dev = pcie->cdns_pcie->dev; + struct device_node *np = dev->of_node; + struct irq_domain *parent_domain; + struct device_node *parent_np; + + if (!of_find_property(np, "interrupt-parent", NULL)) { + dev_err(dev, "Can't find interrupt-parent!\n"); + return -EINVAL; + } + + parent_np = of_irq_find_parent(np); + if (!parent_np) { + dev_err(dev, "Can't find node of interrupt-parent!\n"); + return -ENXIO; + } + + parent_domain = irq_find_host(parent_np); + of_node_put(parent_np); + if (!parent_domain) { + dev_err(dev, "Can't find domain of interrupt-parent!\n"); + return -ENXIO; + } + + return sg2042_pcie_create_msi_domain(pcie, parent_domain); +} + +static int sg2042_pcie_init_msi_data(struct sg2042_pcie *pcie) +{ + struct device *dev = pcie->cdns_pcie->dev; + u32 value; + int ret; + + raw_spin_lock_init(&pcie->lock); + + /* + * Though the PCIe controller can address >32-bit address space, to + * facilitate endpoints that support only 32-bit MSI target address, + * the mask is set to 32-bit to make sure that MSI target address is + * always a 32-bit address + */ + ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32)); + if (ret < 0) + return ret; + + pcie->msi_virt = dma_alloc_coherent(dev, BYTE_NUM_PER_MSI_VEC * MAX_MSI_IRQS, + &pcie->msi_phys, GFP_KERNEL); + if (!pcie->msi_virt) + return -ENOMEM; + + /* Program the msi address and size */ + if (pcie->link_id == 1) { + regmap_write(pcie->syscon, REG_LINK1_MSI_ADDR_LOW, + lower_32_bits(pcie->msi_phys)); + regmap_write(pcie->syscon, REG_LINK1_MSI_ADDR_HIGH, + upper_32_bits(pcie->msi_phys)); + + regmap_read(pcie->syscon, REG_LINK1_MSI_ADDR_SIZE, &value); + value = (value & REG_LINK1_MSI_ADDR_SIZE_MASK) | MAX_MSI_IRQS; + regmap_write(pcie->syscon, REG_LINK1_MSI_ADDR_SIZE, value); + } else { + regmap_write(pcie->syscon, REG_LINK0_MSI_ADDR_LOW, + lower_32_bits(pcie->msi_phys)); + regmap_write(pcie->syscon, REG_LINK0_MSI_ADDR_HIGH, + upper_32_bits(pcie->msi_phys)); + + regmap_read(pcie->syscon, REG_LINK0_MSI_ADDR_SIZE, &value); + value = (value & REG_LINK0_MSI_ADDR_SIZE_MASK) | (MAX_MSI_IRQS << 16); + regmap_write(pcie->syscon, REG_LINK0_MSI_ADDR_SIZE, value); + } + + return 0; +} + +static irqreturn_t sg2042_pcie_msi_handle_irq(struct sg2042_pcie *pcie) +{ + u32 i, pos; + unsigned long val; + u32 status, num_vectors; + irqreturn_t ret = IRQ_NONE; + + num_vectors = pcie->num_applied_vecs; + for (i = 0; i <= num_vectors; i++) { + status = readl((void *)(pcie->msi_virt + i * BYTE_NUM_PER_MSI_VEC)); + if (!status) + continue; + + ret = IRQ_HANDLED; + val = status; + pos = 0; + while ((pos = find_next_bit(&val, MAX_MSI_IRQS_PER_CTRL, + pos)) != MAX_MSI_IRQS_PER_CTRL) { + generic_handle_domain_irq(pcie->msi_domain->parent, + (i * MAX_MSI_IRQS_PER_CTRL) + + pos); + pos++; + } + writel(0, ((void *)(pcie->msi_virt) + i * BYTE_NUM_PER_MSI_VEC)); + } + return ret; +} + +static void sg2042_pcie_msi_chained_isr(struct irq_desc *desc) +{ + struct irq_chip *chip = irq_desc_get_chip(desc); + u32 status, st_msi_in_bit; + struct sg2042_pcie *pcie; + + chained_irq_enter(chip, desc); + + pcie = irq_desc_get_handler_data(desc); + if (pcie->link_id == 1) + st_msi_in_bit = REG_STATUS_LINK1_BIT; + else + st_msi_in_bit = REG_STATUS_LINK0_BIT; + + regmap_read(pcie->syscon, REG_STATUS, &status); + if ((status >> st_msi_in_bit) & 0x1) { + sg2042_pcie_msi_clear_status(pcie); + + sg2042_pcie_msi_handle_irq(pcie); + } + + chained_irq_exit(chip, desc); +} + +static int sg2042_pcie_setup_msi(struct sg2042_pcie *pcie, struct platform_device *pdev) +{ + struct device *dev = pcie->cdns_pcie->dev; + struct fwnode_handle *fwnode = of_node_to_fwnode(dev->of_node); + struct irq_domain *parent_domain; + int ret = 0; + + parent_domain = irq_domain_create_linear(fwnode, MSI_DEF_NUM_VECTORS, + &sg2042_pcie_msi_domain_ops, pcie); + if (!parent_domain) { + dev_err(dev, "Failed to create IRQ domain\n"); + return -ENOMEM; + } + irq_domain_update_bus_token(parent_domain, DOMAIN_BUS_NEXUS); + + ret = sg2042_pcie_create_msi_domain(pcie, parent_domain); + if (ret) { + irq_domain_remove(parent_domain); + return ret; + } + + ret = sg2042_pcie_init_msi_data(pcie); + if (ret) { + dev_err(dev, "Failed to initialize msi data!\n"); + return ret; + } + + ret = platform_get_irq_byname(pdev, "msi"); + if (ret <= 0) { + dev_err(dev, "failed to get MSI irq\n"); + return ret; + } + pcie->msi_irq = ret; + + irq_set_chained_handler_and_data(pcie->msi_irq, + sg2042_pcie_msi_chained_isr, pcie); + + return 0; +} + +static void sg2042_pcie_free_msi(struct sg2042_pcie *pcie) +{ + struct device *dev = pcie->cdns_pcie->dev; + + if (pcie->msi_irq) + irq_set_chained_handler_and_data(pcie->msi_irq, NULL, NULL); + + if (pcie->msi_virt) + dma_free_coherent(dev, BYTE_NUM_PER_MSI_VEC * MAX_MSI_IRQS, + pcie->msi_virt, pcie->msi_phys); +} + +static u64 sg2042_cdns_pcie_cpu_addr_fixup(struct cdns_pcie *pcie, u64 cpu_addr) +{ + return cpu_addr & SG2042_CDNS_PLAT_CPU_TO_BUS_ADDR; +} + +static const struct cdns_pcie_ops sg2042_cdns_pcie_ops = { + .cpu_addr_fixup = sg2042_cdns_pcie_cpu_addr_fixup, +}; + +/* + * SG2042 only support 4-byte aligned access, so for the rootbus (i.e. to read + * the PCIe controller itself, read32 is required. For non-rootbus (i.e. to read + * the PCIe peripheral registers, supports 1/2/4 byte aligned access, so + * directly use read should be fine. + * The same is true for write. + */ +static int sg2042_pcie_config_read(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 *value) +{ + if (pci_is_root_bus(bus)) + return pci_generic_config_read32(bus, devfn, where, size, + value); + + return pci_generic_config_read(bus, devfn, where, size, value); +} + +static int sg2042_pcie_config_write(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 value) +{ + if (pci_is_root_bus(bus)) + return pci_generic_config_write32(bus, devfn, where, size, + value); + + return pci_generic_config_write(bus, devfn, where, size, value); +} + +static struct pci_ops sg2042_pcie_host_ops = { + .map_bus = cdns_pci_map_bus, + .read = sg2042_pcie_config_read, + .write = sg2042_pcie_config_write, +}; + +static int sg2042_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct pci_host_bridge *bridge; + struct device_node *np_syscon; + struct cdns_pcie *cdns_pcie; + struct sg2042_pcie *pcie; + struct cdns_pcie_rc *rc; + struct regmap *syscon; + int ret; + + if (!IS_ENABLED(CONFIG_PCIE_CADENCE_HOST)) + return -ENODEV; + + pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL); + if (!pcie) + return -ENOMEM; + + bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc)); + if (!bridge) { + dev_err(dev, "Failed to alloc host bridge!\n"); + return -ENOMEM; + } + bridge->ops = &sg2042_pcie_host_ops; + + rc = pci_host_bridge_priv(bridge); + cdns_pcie = &rc->pcie; + cdns_pcie->dev = dev; + cdns_pcie->ops = &sg2042_cdns_pcie_ops; + pcie->cdns_pcie = cdns_pcie; + + np_syscon = of_parse_phandle(np, "sophgo,syscon-pcie-ctrl", 0); + if (!np_syscon) { + dev_err(dev, "Failed to get syscon node\n"); + return -ENOMEM; + } + syscon = syscon_node_to_regmap(np_syscon); + if (IS_ERR(syscon)) { + dev_err(dev, "Failed to get regmap for syscon\n"); + return -ENOMEM; + } + pcie->syscon = syscon; + + if (of_property_read_u32(np, "sophgo,link-id", &pcie->link_id)) { + dev_err(dev, "Unable to parse link ID\n"); + return -EINVAL; + } + + pcie->internal_msi = 0; + if (of_property_read_bool(np, "sophgo,internal-msi")) + pcie->internal_msi = 1; + + platform_set_drvdata(pdev, pcie); + + pm_runtime_enable(dev); + + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + dev_err(dev, "pm_runtime_get_sync failed\n"); + goto err_get_sync; + } + + if (pcie->internal_msi) { + ret = sg2042_pcie_setup_msi(pcie, pdev); + if (ret < 0) + goto err_setup_msi; + } else { + ret = sg2042_pcie_setup_msi_external(pcie); + if (ret < 0) + goto err_setup_msi; + } + + ret = cdns_pcie_init_phy(dev, cdns_pcie); + if (ret) { + dev_err(dev, "Failed to init phy!\n"); + goto err_setup_msi; + } + + ret = cdns_pcie_host_setup(rc); + if (ret < 0) { + dev_err(dev, "Failed to setup host!\n"); + goto err_host_setup; + } + + return 0; + +err_host_setup: + cdns_pcie_disable_phy(cdns_pcie); + +err_setup_msi: + sg2042_pcie_free_msi(pcie); + +err_get_sync: + pm_runtime_put(dev); + pm_runtime_disable(dev); + + return ret; +} + +static void sg2042_pcie_shutdown(struct platform_device *pdev) +{ + struct sg2042_pcie *pcie = platform_get_drvdata(pdev); + struct cdns_pcie *cdns_pcie = pcie->cdns_pcie; + struct device *dev = &pdev->dev; + + sg2042_pcie_free_msi(pcie); + + cdns_pcie_disable_phy(cdns_pcie); + + pm_runtime_put(dev); + pm_runtime_disable(dev); +} + +static const struct of_device_id sg2042_pcie_of_match[] = { + { .compatible = "sophgo,sg2042-pcie-host" }, + {}, +}; + +static struct platform_driver sg2042_pcie_driver = { + .driver = { + .name = "sg2042-pcie", + .of_match_table = sg2042_pcie_of_match, + .pm = &cdns_pcie_pm_ops, + }, + .probe = sg2042_pcie_probe, + .shutdown = sg2042_pcie_shutdown, +}; +builtin_platform_driver(sg2042_pcie_driver); -- 2.34.1