// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2006 PA Semi, Inc * * Authors: Kip Walker, PA Semi * Olof Johansson, PA Semi * * Maintained by: Olof Johansson * * Based on arch/powerpc/platforms/maple/pci.c */ #include #include #include #include #include #include #include "pasemi.h" #define PA_PXP_CFA(bus, devfn, off) (((bus) << 20) | ((devfn) << 12) | (off)) static inline int pa_pxp_offset_valid(u8 bus, u8 devfn, int offset) { /* Device 0 Function 0 is special: It's config space spans function 1 as * well, so allow larger offset. It's really a two-function device but the * second function does not probe. */ if (bus == 0 && devfn == 0) return offset < 8192; else return offset < 4096; } static void volatile __iomem *pa_pxp_cfg_addr(struct pci_controller *hose, u8 bus, u8 devfn, int offset) { return hose->cfg_data + PA_PXP_CFA(bus, devfn, offset); } static inline int is_root_port(int busno, int devfn) { return ((busno == 0) && (PCI_FUNC(devfn) < 4) && ((PCI_SLOT(devfn) == 16) || (PCI_SLOT(devfn) == 17))); } static inline int is_5945_reg(int reg) { return (((reg >= 0x18) && (reg < 0x34)) || ((reg >= 0x158) && (reg < 0x178))); } static int workaround_5945(struct pci_bus *bus, unsigned int devfn, int offset, int len, u32 *val) { struct pci_controller *hose; void volatile __iomem *addr, *dummy; int byte; u32 tmp; if (!is_root_port(bus->number, devfn) || !is_5945_reg(offset)) return 0; hose = pci_bus_to_host(bus); addr = pa_pxp_cfg_addr(hose, bus->number, devfn, offset & ~0x3); byte = offset & 0x3; /* Workaround bug 5945: write 0 to a dummy register before reading, * and write back what we read. We must read/write the full 32-bit * contents so we need to shift and mask by hand. */ dummy = pa_pxp_cfg_addr(hose, bus->number, devfn, 0x10); out_le32(dummy, 0); tmp = in_le32(addr); out_le32(addr, tmp); switch (len) { case 1: *val = (tmp >> (8*byte)) & 0xff; break; case 2: if (byte == 0) *val = tmp & 0xffff; else *val = (tmp >> 16) & 0xffff; break; default: *val = tmp; break; } return 1; } #ifdef CONFIG_PPC_PASEMI_NEMO #define PXP_ERR_CFG_REG 0x4 #define PXP_IGNORE_PCIE_ERRORS 0x800 #define SB600_BUS 5 static void sb600_set_flag(int bus) { static void __iomem *iob_mapbase = NULL; struct resource res; struct device_node *dn; int err; if (iob_mapbase == NULL) { dn = of_find_compatible_node(NULL, "isa", "pasemi,1682m-iob"); if (!dn) { pr_crit("NEMO SB600 missing iob node\n"); return; } err = of_address_to_resource(dn, 0, &res); of_node_put(dn); if (err) { pr_crit("NEMO SB600 missing resource\n"); return; } pr_info("NEMO SB600 IOB base %08llx\n",res.start); iob_mapbase = ioremap(res.start + 0x100, 0x94); } if (iob_mapbase != NULL) { if (bus == SB600_BUS) { /* * This is the SB600's bus, tell the PCI-e root port * to allow non-zero devices to enumerate. */ out_le32(iob_mapbase + PXP_ERR_CFG_REG, in_le32(iob_mapbase + PXP_ERR_CFG_REG) | PXP_IGNORE_PCIE_ERRORS); } else { /* * Only scan device 0 on other busses */ out_le32(iob_mapbase + PXP_ERR_CFG_REG, in_le32(iob_mapbase + PXP_ERR_CFG_REG) & ~PXP_IGNORE_PCIE_ERRORS); } } } #else static void sb600_set_flag(int bus) { } #endif static int pa_pxp_read_config(struct pci_bus *bus, unsigned int devfn, int offset, int len, u32 *val) { struct pci_controller *hose; void volatile __iomem *addr; hose = pci_bus_to_host(bus); if (!hose) return PCIBIOS_DEVICE_NOT_FOUND; if (!pa_pxp_offset_valid(bus->number, devfn, offset)) return PCIBIOS_BAD_REGISTER_NUMBER; if (workaround_5945(bus, devfn, offset, len, val)) return PCIBIOS_SUCCESSFUL; addr = pa_pxp_cfg_addr(hose, bus->number, devfn, offset); sb600_set_flag(bus->number); /* * Note: the caller has already checked that offset is * suitably aligned and that len is 1, 2 or 4. */ switch (len) { case 1: *val = in_8(addr); break; case 2: *val = in_le16(addr); break; default: *val = in_le32(addr); break; } return PCIBIOS_SUCCESSFUL; } static int pa_pxp_write_config(struct pci_bus *bus, unsigned int devfn, int offset, int len, u32 val) { struct pci_controller *hose; void volatile __iomem *addr; hose = pci_bus_to_host(bus); if (!hose) return PCIBIOS_DEVICE_NOT_FOUND; if (!pa_pxp_offset_valid(bus->number, devfn, offset)) return PCIBIOS_BAD_REGISTER_NUMBER; addr = pa_pxp_cfg_addr(hose, bus->number, devfn, offset); sb600_set_flag(bus->number); /* * Note: the caller has already checked that offset is * suitably aligned and that len is 1, 2 or 4. */ switch (len) { case 1: out_8(addr, val); break; case 2: out_le16(addr, val); break; default: out_le32(addr, val); break; } return PCIBIOS_SUCCESSFUL; } static struct pci_ops pa_pxp_ops = { .read = pa_pxp_read_config, .write = pa_pxp_write_config, }; static void __init setup_pa_pxp(struct pci_controller *hose) { hose->ops = &pa_pxp_ops; hose->cfg_data = ioremap(0xe0000000, 0x10000000); } static int __init pas_add_bridge(struct device_node *dev) { struct pci_controller *hose; pr_debug("Adding PCI host bridge %pOF\n", dev); hose = pcibios_alloc_controller(dev); if (!hose) return -ENOMEM; hose->first_busno = 0; hose->last_busno = 0xff; hose->controller_ops = pasemi_pci_controller_ops; setup_pa_pxp(hose); pr_info("Found PA-PXP PCI host bridge.\n"); /* Interpret the "ranges" property */ pci_process_bridge_OF_ranges(hose, dev, 1); /* * Scan for an isa bridge. This is needed to find the SB600 on the nemo * and does nothing on machines without one. */ isa_bridge_find_early(hose); return 0; } void __init pas_pci_init(void) { struct device_node *np, *root; int res; root = of_find_node_by_path("/"); if (!root) { pr_crit("pas_pci_init: can't find root of device tree\n"); return; } pci_set_flags(PCI_SCAN_ALL_PCIE_DEVS); np = of_find_compatible_node(root, NULL, "pasemi,rootbus"); if (np) { res = pas_add_bridge(np); of_node_put(np); } } void __iomem *__init pasemi_pci_getcfgaddr(struct pci_dev *dev, int offset) { struct pci_controller *hose; hose = pci_bus_to_host(dev->bus); return (void __iomem *)pa_pxp_cfg_addr(hose, dev->bus->number, dev->devfn, offset); } struct pci_controller_ops pasemi_pci_controller_ops;