diff options
Diffstat (limited to 'drivers/pci/controller/pci-xgene.c')
| -rw-r--r-- | drivers/pci/controller/pci-xgene.c | 650 |
1 files changed, 650 insertions, 0 deletions
diff --git a/drivers/pci/controller/pci-xgene.c b/drivers/pci/controller/pci-xgene.c new file mode 100644 index 000000000..549d3bd6d --- /dev/null +++ b/drivers/pci/controller/pci-xgene.c @@ -0,0 +1,650 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * APM X-Gene PCIe Driver + * + * Copyright (c) 2014 Applied Micro Circuits Corporation. + * + * Author: Tanmay Inamdar <tinamdar@apm.com>. + */ +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/jiffies.h> +#include <linux/memblock.h> +#include <linux/init.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_pci.h> +#include <linux/pci.h> +#include <linux/pci-acpi.h> +#include <linux/pci-ecam.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#include "../pci.h" + +#define PCIECORE_CTLANDSTATUS 0x50 +#define PIM1_1L 0x80 +#define IBAR2 0x98 +#define IR2MSK 0x9c +#define PIM2_1L 0xa0 +#define IBAR3L 0xb4 +#define IR3MSKL 0xbc +#define PIM3_1L 0xc4 +#define OMR1BARL 0x100 +#define OMR2BARL 0x118 +#define OMR3BARL 0x130 +#define CFGBARL 0x154 +#define CFGBARH 0x158 +#define CFGCTL 0x15c +#define RTDID 0x160 +#define BRIDGE_CFG_0 0x2000 +#define BRIDGE_CFG_4 0x2010 +#define BRIDGE_STATUS_0 0x2600 + +#define LINK_UP_MASK 0x00000100 +#define AXI_EP_CFG_ACCESS 0x10000 +#define EN_COHERENCY 0xF0000000 +#define EN_REG 0x00000001 +#define OB_LO_IO 0x00000002 +#define XGENE_PCIE_DEVICEID 0xE004 +#define PIPE_PHY_RATE_RD(src) ((0xc000 & (u32)(src)) >> 0xe) + +#define XGENE_V1_PCI_EXP_CAP 0x40 + +/* PCIe IP version */ +#define XGENE_PCIE_IP_VER_UNKN 0 +#define XGENE_PCIE_IP_VER_1 1 +#define XGENE_PCIE_IP_VER_2 2 + +#if defined(CONFIG_PCI_XGENE) || (defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)) +struct xgene_pcie { + struct device_node *node; + struct device *dev; + struct clk *clk; + void __iomem *csr_base; + void __iomem *cfg_base; + unsigned long cfg_addr; + bool link_up; + u32 version; +}; + +static u32 xgene_pcie_readl(struct xgene_pcie *port, u32 reg) +{ + return readl(port->csr_base + reg); +} + +static void xgene_pcie_writel(struct xgene_pcie *port, u32 reg, u32 val) +{ + writel(val, port->csr_base + reg); +} + +static inline u32 pcie_bar_low_val(u32 addr, u32 flags) +{ + return (addr & PCI_BASE_ADDRESS_MEM_MASK) | flags; +} + +static inline struct xgene_pcie *pcie_bus_to_port(struct pci_bus *bus) +{ + struct pci_config_window *cfg; + + if (acpi_disabled) + return (struct xgene_pcie *)(bus->sysdata); + + cfg = bus->sysdata; + return (struct xgene_pcie *)(cfg->priv); +} + +/* + * When the address bit [17:16] is 2'b01, the Configuration access will be + * treated as Type 1 and it will be forwarded to external PCIe device. + */ +static void __iomem *xgene_pcie_get_cfg_base(struct pci_bus *bus) +{ + struct xgene_pcie *port = pcie_bus_to_port(bus); + + if (bus->number >= (bus->primary + 1)) + return port->cfg_base + AXI_EP_CFG_ACCESS; + + return port->cfg_base; +} + +/* + * For Configuration request, RTDID register is used as Bus Number, + * Device Number and Function number of the header fields. + */ +static void xgene_pcie_set_rtdid_reg(struct pci_bus *bus, uint devfn) +{ + struct xgene_pcie *port = pcie_bus_to_port(bus); + unsigned int b, d, f; + u32 rtdid_val = 0; + + b = bus->number; + d = PCI_SLOT(devfn); + f = PCI_FUNC(devfn); + + if (!pci_is_root_bus(bus)) + rtdid_val = (b << 8) | (d << 3) | f; + + xgene_pcie_writel(port, RTDID, rtdid_val); + /* read the register back to ensure flush */ + xgene_pcie_readl(port, RTDID); +} + +/* + * X-Gene PCIe port uses BAR0-BAR1 of RC's configuration space as + * the translation from PCI bus to native BUS. Entire DDR region + * is mapped into PCIe space using these registers, so it can be + * reached by DMA from EP devices. The BAR0/1 of bridge should be + * hidden during enumeration to avoid the sizing and resource allocation + * by PCIe core. + */ +static bool xgene_pcie_hide_rc_bars(struct pci_bus *bus, int offset) +{ + if (pci_is_root_bus(bus) && ((offset == PCI_BASE_ADDRESS_0) || + (offset == PCI_BASE_ADDRESS_1))) + return true; + + return false; +} + +static void __iomem *xgene_pcie_map_bus(struct pci_bus *bus, unsigned int devfn, + int offset) +{ + if ((pci_is_root_bus(bus) && devfn != 0) || + xgene_pcie_hide_rc_bars(bus, offset)) + return NULL; + + xgene_pcie_set_rtdid_reg(bus, devfn); + return xgene_pcie_get_cfg_base(bus) + offset; +} + +static int xgene_pcie_config_read32(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 *val) +{ + struct xgene_pcie *port = pcie_bus_to_port(bus); + + if (pci_generic_config_read32(bus, devfn, where & ~0x3, 4, val) != + PCIBIOS_SUCCESSFUL) + return PCIBIOS_DEVICE_NOT_FOUND; + + /* + * The v1 controller has a bug in its Configuration Request Retry + * Status (CRS) logic: when CRS Software Visibility is enabled and + * we read the Vendor and Device ID of a non-existent device, the + * controller fabricates return data of 0xFFFF0001 ("device exists + * but is not ready") instead of 0xFFFFFFFF (PCI_ERROR_RESPONSE) + * ("device does not exist"). This causes the PCI core to retry + * the read until it times out. Avoid this by not claiming to + * support CRS SV. + */ + if (pci_is_root_bus(bus) && (port->version == XGENE_PCIE_IP_VER_1) && + ((where & ~0x3) == XGENE_V1_PCI_EXP_CAP + PCI_EXP_RTCTL)) + *val &= ~(PCI_EXP_RTCAP_CRSVIS << 16); + + if (size <= 2) + *val = (*val >> (8 * (where & 3))) & ((1 << (size * 8)) - 1); + + return PCIBIOS_SUCCESSFUL; +} +#endif + +#if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS) +static int xgene_get_csr_resource(struct acpi_device *adev, + struct resource *res) +{ + struct device *dev = &adev->dev; + struct resource_entry *entry; + struct list_head list; + unsigned long flags; + int ret; + + INIT_LIST_HEAD(&list); + flags = IORESOURCE_MEM; + ret = acpi_dev_get_resources(adev, &list, + acpi_dev_filter_resource_type_cb, + (void *) flags); + if (ret < 0) { + dev_err(dev, "failed to parse _CRS method, error code %d\n", + ret); + return ret; + } + + if (ret == 0) { + dev_err(dev, "no IO and memory resources present in _CRS\n"); + return -EINVAL; + } + + entry = list_first_entry(&list, struct resource_entry, node); + *res = *entry->res; + acpi_dev_free_resource_list(&list); + return 0; +} + +static int xgene_pcie_ecam_init(struct pci_config_window *cfg, u32 ipversion) +{ + struct device *dev = cfg->parent; + struct acpi_device *adev = to_acpi_device(dev); + struct xgene_pcie *port; + struct resource csr; + int ret; + + port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL); + if (!port) + return -ENOMEM; + + ret = xgene_get_csr_resource(adev, &csr); + if (ret) { + dev_err(dev, "can't get CSR resource\n"); + return ret; + } + port->csr_base = devm_pci_remap_cfg_resource(dev, &csr); + if (IS_ERR(port->csr_base)) + return PTR_ERR(port->csr_base); + + port->cfg_base = cfg->win; + port->version = ipversion; + + cfg->priv = port; + return 0; +} + +static int xgene_v1_pcie_ecam_init(struct pci_config_window *cfg) +{ + return xgene_pcie_ecam_init(cfg, XGENE_PCIE_IP_VER_1); +} + +const struct pci_ecam_ops xgene_v1_pcie_ecam_ops = { + .init = xgene_v1_pcie_ecam_init, + .pci_ops = { + .map_bus = xgene_pcie_map_bus, + .read = xgene_pcie_config_read32, + .write = pci_generic_config_write, + } +}; + +static int xgene_v2_pcie_ecam_init(struct pci_config_window *cfg) +{ + return xgene_pcie_ecam_init(cfg, XGENE_PCIE_IP_VER_2); +} + +const struct pci_ecam_ops xgene_v2_pcie_ecam_ops = { + .init = xgene_v2_pcie_ecam_init, + .pci_ops = { + .map_bus = xgene_pcie_map_bus, + .read = xgene_pcie_config_read32, + .write = pci_generic_config_write, + } +}; +#endif + +#if defined(CONFIG_PCI_XGENE) +static u64 xgene_pcie_set_ib_mask(struct xgene_pcie *port, u32 addr, + u32 flags, u64 size) +{ + u64 mask = (~(size - 1) & PCI_BASE_ADDRESS_MEM_MASK) | flags; + u32 val32 = 0; + u32 val; + + val32 = xgene_pcie_readl(port, addr); + val = (val32 & 0x0000ffff) | (lower_32_bits(mask) << 16); + xgene_pcie_writel(port, addr, val); + + val32 = xgene_pcie_readl(port, addr + 0x04); + val = (val32 & 0xffff0000) | (lower_32_bits(mask) >> 16); + xgene_pcie_writel(port, addr + 0x04, val); + + val32 = xgene_pcie_readl(port, addr + 0x04); + val = (val32 & 0x0000ffff) | (upper_32_bits(mask) << 16); + xgene_pcie_writel(port, addr + 0x04, val); + + val32 = xgene_pcie_readl(port, addr + 0x08); + val = (val32 & 0xffff0000) | (upper_32_bits(mask) >> 16); + xgene_pcie_writel(port, addr + 0x08, val); + + return mask; +} + +static void xgene_pcie_linkup(struct xgene_pcie *port, + u32 *lanes, u32 *speed) +{ + u32 val32; + + port->link_up = false; + val32 = xgene_pcie_readl(port, PCIECORE_CTLANDSTATUS); + if (val32 & LINK_UP_MASK) { + port->link_up = true; + *speed = PIPE_PHY_RATE_RD(val32); + val32 = xgene_pcie_readl(port, BRIDGE_STATUS_0); + *lanes = val32 >> 26; + } +} + +static int xgene_pcie_init_port(struct xgene_pcie *port) +{ + struct device *dev = port->dev; + int rc; + + port->clk = clk_get(dev, NULL); + if (IS_ERR(port->clk)) { + dev_err(dev, "clock not available\n"); + return -ENODEV; + } + + rc = clk_prepare_enable(port->clk); + if (rc) { + dev_err(dev, "clock enable failed\n"); + return rc; + } + + return 0; +} + +static int xgene_pcie_map_reg(struct xgene_pcie *port, + struct platform_device *pdev) +{ + struct device *dev = port->dev; + struct resource *res; + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "csr"); + port->csr_base = devm_pci_remap_cfg_resource(dev, res); + if (IS_ERR(port->csr_base)) + return PTR_ERR(port->csr_base); + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg"); + port->cfg_base = devm_ioremap_resource(dev, res); + if (IS_ERR(port->cfg_base)) + return PTR_ERR(port->cfg_base); + port->cfg_addr = res->start; + + return 0; +} + +static void xgene_pcie_setup_ob_reg(struct xgene_pcie *port, + struct resource *res, u32 offset, + u64 cpu_addr, u64 pci_addr) +{ + struct device *dev = port->dev; + resource_size_t size = resource_size(res); + u64 restype = resource_type(res); + u64 mask = 0; + u32 min_size; + u32 flag = EN_REG; + + if (restype == IORESOURCE_MEM) { + min_size = SZ_128M; + } else { + min_size = 128; + flag |= OB_LO_IO; + } + + if (size >= min_size) + mask = ~(size - 1) | flag; + else + dev_warn(dev, "res size 0x%llx less than minimum 0x%x\n", + (u64)size, min_size); + + xgene_pcie_writel(port, offset, lower_32_bits(cpu_addr)); + xgene_pcie_writel(port, offset + 0x04, upper_32_bits(cpu_addr)); + xgene_pcie_writel(port, offset + 0x08, lower_32_bits(mask)); + xgene_pcie_writel(port, offset + 0x0c, upper_32_bits(mask)); + xgene_pcie_writel(port, offset + 0x10, lower_32_bits(pci_addr)); + xgene_pcie_writel(port, offset + 0x14, upper_32_bits(pci_addr)); +} + +static void xgene_pcie_setup_cfg_reg(struct xgene_pcie *port) +{ + u64 addr = port->cfg_addr; + + xgene_pcie_writel(port, CFGBARL, lower_32_bits(addr)); + xgene_pcie_writel(port, CFGBARH, upper_32_bits(addr)); + xgene_pcie_writel(port, CFGCTL, EN_REG); +} + +static int xgene_pcie_map_ranges(struct xgene_pcie *port) +{ + struct pci_host_bridge *bridge = pci_host_bridge_from_priv(port); + struct resource_entry *window; + struct device *dev = port->dev; + + resource_list_for_each_entry(window, &bridge->windows) { + struct resource *res = window->res; + u64 restype = resource_type(res); + + dev_dbg(dev, "%pR\n", res); + + switch (restype) { + case IORESOURCE_IO: + xgene_pcie_setup_ob_reg(port, res, OMR3BARL, + pci_pio_to_address(res->start), + res->start - window->offset); + break; + case IORESOURCE_MEM: + if (res->flags & IORESOURCE_PREFETCH) + xgene_pcie_setup_ob_reg(port, res, OMR2BARL, + res->start, + res->start - + window->offset); + else + xgene_pcie_setup_ob_reg(port, res, OMR1BARL, + res->start, + res->start - + window->offset); + break; + case IORESOURCE_BUS: + break; + default: + dev_err(dev, "invalid resource %pR\n", res); + return -EINVAL; + } + } + xgene_pcie_setup_cfg_reg(port); + return 0; +} + +static void xgene_pcie_setup_pims(struct xgene_pcie *port, u32 pim_reg, + u64 pim, u64 size) +{ + xgene_pcie_writel(port, pim_reg, lower_32_bits(pim)); + xgene_pcie_writel(port, pim_reg + 0x04, + upper_32_bits(pim) | EN_COHERENCY); + xgene_pcie_writel(port, pim_reg + 0x10, lower_32_bits(size)); + xgene_pcie_writel(port, pim_reg + 0x14, upper_32_bits(size)); +} + +/* + * X-Gene PCIe support maximum 3 inbound memory regions + * This function helps to select a region based on size of region + */ +static int xgene_pcie_select_ib_reg(u8 *ib_reg_mask, u64 size) +{ + if ((size > 4) && (size < SZ_16M) && !(*ib_reg_mask & (1 << 1))) { + *ib_reg_mask |= (1 << 1); + return 1; + } + + if ((size > SZ_1K) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 0))) { + *ib_reg_mask |= (1 << 0); + return 0; + } + + if ((size > SZ_1M) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 2))) { + *ib_reg_mask |= (1 << 2); + return 2; + } + + return -EINVAL; +} + +static void xgene_pcie_setup_ib_reg(struct xgene_pcie *port, + struct of_pci_range *range, u8 *ib_reg_mask) +{ + void __iomem *cfg_base = port->cfg_base; + struct device *dev = port->dev; + void __iomem *bar_addr; + u32 pim_reg; + u64 cpu_addr = range->cpu_addr; + u64 pci_addr = range->pci_addr; + u64 size = range->size; + u64 mask = ~(size - 1) | EN_REG; + u32 flags = PCI_BASE_ADDRESS_MEM_TYPE_64; + u32 bar_low; + int region; + + region = xgene_pcie_select_ib_reg(ib_reg_mask, range->size); + if (region < 0) { + dev_warn(dev, "invalid pcie dma-range config\n"); + return; + } + + if (range->flags & IORESOURCE_PREFETCH) + flags |= PCI_BASE_ADDRESS_MEM_PREFETCH; + + bar_low = pcie_bar_low_val((u32)cpu_addr, flags); + switch (region) { + case 0: + xgene_pcie_set_ib_mask(port, BRIDGE_CFG_4, flags, size); + bar_addr = cfg_base + PCI_BASE_ADDRESS_0; + writel(bar_low, bar_addr); + writel(upper_32_bits(cpu_addr), bar_addr + 0x4); + pim_reg = PIM1_1L; + break; + case 1: + xgene_pcie_writel(port, IBAR2, bar_low); + xgene_pcie_writel(port, IR2MSK, lower_32_bits(mask)); + pim_reg = PIM2_1L; + break; + case 2: + xgene_pcie_writel(port, IBAR3L, bar_low); + xgene_pcie_writel(port, IBAR3L + 0x4, upper_32_bits(cpu_addr)); + xgene_pcie_writel(port, IR3MSKL, lower_32_bits(mask)); + xgene_pcie_writel(port, IR3MSKL + 0x4, upper_32_bits(mask)); + pim_reg = PIM3_1L; + break; + } + + xgene_pcie_setup_pims(port, pim_reg, pci_addr, ~(size - 1)); +} + +static int xgene_pcie_parse_map_dma_ranges(struct xgene_pcie *port) +{ + struct device_node *np = port->node; + struct of_pci_range range; + struct of_pci_range_parser parser; + struct device *dev = port->dev; + u8 ib_reg_mask = 0; + + if (of_pci_dma_range_parser_init(&parser, np)) { + dev_err(dev, "missing dma-ranges property\n"); + return -EINVAL; + } + + /* Get the dma-ranges from DT */ + for_each_of_pci_range(&parser, &range) { + u64 end = range.cpu_addr + range.size - 1; + + dev_dbg(dev, "0x%08x 0x%016llx..0x%016llx -> 0x%016llx\n", + range.flags, range.cpu_addr, end, range.pci_addr); + xgene_pcie_setup_ib_reg(port, &range, &ib_reg_mask); + } + return 0; +} + +/* clear BAR configuration which was done by firmware */ +static void xgene_pcie_clear_config(struct xgene_pcie *port) +{ + int i; + + for (i = PIM1_1L; i <= CFGCTL; i += 4) + xgene_pcie_writel(port, i, 0); +} + +static int xgene_pcie_setup(struct xgene_pcie *port) +{ + struct device *dev = port->dev; + u32 val, lanes = 0, speed = 0; + int ret; + + xgene_pcie_clear_config(port); + + /* setup the vendor and device IDs correctly */ + val = (XGENE_PCIE_DEVICEID << 16) | PCI_VENDOR_ID_AMCC; + xgene_pcie_writel(port, BRIDGE_CFG_0, val); + + ret = xgene_pcie_map_ranges(port); + if (ret) + return ret; + + ret = xgene_pcie_parse_map_dma_ranges(port); + if (ret) + return ret; + + xgene_pcie_linkup(port, &lanes, &speed); + if (!port->link_up) + dev_info(dev, "(rc) link down\n"); + else + dev_info(dev, "(rc) x%d gen-%d link up\n", lanes, speed + 1); + return 0; +} + +static struct pci_ops xgene_pcie_ops = { + .map_bus = xgene_pcie_map_bus, + .read = xgene_pcie_config_read32, + .write = pci_generic_config_write32, +}; + +static int xgene_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *dn = dev->of_node; + struct xgene_pcie *port; + struct pci_host_bridge *bridge; + int ret; + + bridge = devm_pci_alloc_host_bridge(dev, sizeof(*port)); + if (!bridge) + return -ENOMEM; + + port = pci_host_bridge_priv(bridge); + + port->node = of_node_get(dn); + port->dev = dev; + + port->version = XGENE_PCIE_IP_VER_UNKN; + if (of_device_is_compatible(port->node, "apm,xgene-pcie")) + port->version = XGENE_PCIE_IP_VER_1; + + ret = xgene_pcie_map_reg(port, pdev); + if (ret) + return ret; + + ret = xgene_pcie_init_port(port); + if (ret) + return ret; + + ret = xgene_pcie_setup(port); + if (ret) + return ret; + + bridge->sysdata = port; + bridge->ops = &xgene_pcie_ops; + + return pci_host_probe(bridge); +} + +static const struct of_device_id xgene_pcie_match_table[] = { + {.compatible = "apm,xgene-pcie",}, + {}, +}; + +static struct platform_driver xgene_pcie_driver = { + .driver = { + .name = "xgene-pcie", + .of_match_table = xgene_pcie_match_table, + .suppress_bind_attrs = true, + }, + .probe = xgene_pcie_probe, +}; +builtin_platform_driver(xgene_pcie_driver); +#endif |