/*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 1997, Stefan Esser * Copyright (c) 2000, Michael Smith * Copyright (c) 2000, BSDi * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice unmodified, this list of conditions, and the following * disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include static uint32_t pci_docfgregread(int bus, int slot, int func, int reg, int bytes); static int pciereg_cfgread(int bus, unsigned slot, unsigned func, unsigned reg, unsigned bytes); static void pciereg_cfgwrite(int bus, unsigned slot, unsigned func, unsigned reg, int data, unsigned bytes); static int pcireg_cfgread(int bus, int slot, int func, int reg, int bytes); static void pcireg_cfgwrite(int bus, int slot, int func, int reg, int data, int bytes); SYSCTL_DECL(_hw_pci); /* * For amd64 we assume that type 1 I/O port-based access always works. * If an ACPI MCFG table exists, pcie_cfgregopen() will be called to * switch to memory-mapped access. */ int cfgmech = CFGMECH_1; static vm_offset_t pcie_base; static int pcie_minbus, pcie_maxbus; static uint32_t pcie_badslots; static struct mtx pcicfg_mtx; MTX_SYSINIT(pcicfg_mtx, &pcicfg_mtx, "pcicfg_mtx", MTX_SPIN); static int mcfg_enable = 1; SYSCTL_INT(_hw_pci, OID_AUTO, mcfg, CTLFLAG_RDTUN, &mcfg_enable, 0, "Enable support for PCI-e memory mapped config access"); int pci_cfgregopen(void) { return (1); } static uint32_t pci_docfgregread(int bus, int slot, int func, int reg, int bytes) { if (cfgmech == CFGMECH_PCIE && (bus >= pcie_minbus && bus <= pcie_maxbus) && (bus != 0 || !(1 << slot & pcie_badslots))) return (pciereg_cfgread(bus, slot, func, reg, bytes)); else return (pcireg_cfgread(bus, slot, func, reg, bytes)); } /* * Read configuration space register */ u_int32_t pci_cfgregread(int bus, int slot, int func, int reg, int bytes) { uint32_t line; /* * Some BIOS writers seem to want to ignore the spec and put * 0 in the intline rather than 255 to indicate none. Some use * numbers in the range 128-254 to indicate something strange and * apparently undocumented anywhere. Assume these are completely bogus * and map them to 255, which the rest of the PCI code recognizes as * as an invalid IRQ. */ if (reg == PCIR_INTLINE && bytes == 1) { line = pci_docfgregread(bus, slot, func, PCIR_INTLINE, 1); if (line == 0 || line >= 128) line = PCI_INVALID_IRQ; return (line); } return (pci_docfgregread(bus, slot, func, reg, bytes)); } /* * Write configuration space register */ void pci_cfgregwrite(int bus, int slot, int func, int reg, u_int32_t data, int bytes) { if (cfgmech == CFGMECH_PCIE && (bus >= pcie_minbus && bus <= pcie_maxbus) && (bus != 0 || !(1 << slot & pcie_badslots))) pciereg_cfgwrite(bus, slot, func, reg, data, bytes); else pcireg_cfgwrite(bus, slot, func, reg, data, bytes); } /* * Configuration space access using direct register operations */ /* enable configuration space accesses and return data port address */ static int pci_cfgenable(unsigned bus, unsigned slot, unsigned func, int reg, int bytes) { int dataport = 0; if (bus <= PCI_BUSMAX && slot <= PCI_SLOTMAX && func <= PCI_FUNCMAX && (unsigned)reg <= PCI_REGMAX && bytes != 3 && (unsigned)bytes <= 4 && (reg & (bytes - 1)) == 0) { outl(CONF1_ADDR_PORT, (1U << 31) | (bus << 16) | (slot << 11) | (func << 8) | (reg & ~0x03)); dataport = CONF1_DATA_PORT + (reg & 0x03); } return (dataport); } /* disable configuration space accesses */ static void pci_cfgdisable(void) { /* * Do nothing. Writing a 0 to the address port can apparently * confuse some bridges and cause spurious access failures. */ } static int pcireg_cfgread(int bus, int slot, int func, int reg, int bytes) { int data = -1; int port; mtx_lock_spin(&pcicfg_mtx); port = pci_cfgenable(bus, slot, func, reg, bytes); if (port != 0) { switch (bytes) { case 1: data = inb(port); break; case 2: data = inw(port); break; case 4: data = inl(port); break; } pci_cfgdisable(); } mtx_unlock_spin(&pcicfg_mtx); return (data); } static void pcireg_cfgwrite(int bus, int slot, int func, int reg, int data, int bytes) { int port; mtx_lock_spin(&pcicfg_mtx); port = pci_cfgenable(bus, slot, func, reg, bytes); if (port != 0) { switch (bytes) { case 1: outb(port, data); break; case 2: outw(port, data); break; case 4: outl(port, data); break; } pci_cfgdisable(); } mtx_unlock_spin(&pcicfg_mtx); } int pcie_cfgregopen(uint64_t base, uint8_t minbus, uint8_t maxbus) { uint32_t val1, val2; int slot; if (!mcfg_enable) return (0); if (minbus != 0) return (0); if (bootverbose) printf("PCIe: Memory Mapped configuration base @ 0x%lx\n", base); /* XXX: We should make sure this really fits into the direct map. */ pcie_base = (vm_offset_t)pmap_mapdev_pciecfg(base, (maxbus + 1) << 20); pcie_minbus = minbus; pcie_maxbus = maxbus; cfgmech = CFGMECH_PCIE; /* * On some AMD systems, some of the devices on bus 0 are * inaccessible using memory-mapped PCI config access. Walk * bus 0 looking for such devices. For these devices, we will * fall back to using type 1 config access instead. */ if (pci_cfgregopen() != 0) { for (slot = 0; slot <= PCI_SLOTMAX; slot++) { val1 = pcireg_cfgread(0, slot, 0, 0, 4); if (val1 == 0xffffffff) continue; val2 = pciereg_cfgread(0, slot, 0, 0, 4); if (val2 != val1) pcie_badslots |= (1 << slot); } } return (1); } #define PCIE_VADDR(base, reg, bus, slot, func) \ ((base) + \ ((((bus) & 0xff) << 20) | \ (((slot) & 0x1f) << 15) | \ (((func) & 0x7) << 12) | \ ((reg) & 0xfff))) /* * AMD BIOS And Kernel Developer's Guides for CPU families starting with 10h * have a requirement that all accesses to the memory mapped PCI configuration * space are done using AX class of registers. * Since other vendors do not currently have any contradicting requirements * the AMD access pattern is applied universally. */ static int pciereg_cfgread(int bus, unsigned slot, unsigned func, unsigned reg, unsigned bytes) { vm_offset_t va; int data = -1; if (bus < pcie_minbus || bus > pcie_maxbus || slot > PCI_SLOTMAX || func > PCI_FUNCMAX || reg > PCIE_REGMAX) return (-1); va = PCIE_VADDR(pcie_base, reg, bus, slot, func); switch (bytes) { case 4: __asm("movl %1, %0" : "=a" (data) : "m" (*(volatile uint32_t *)va)); break; case 2: __asm("movzwl %1, %0" : "=a" (data) : "m" (*(volatile uint16_t *)va)); break; case 1: __asm("movzbl %1, %0" : "=a" (data) : "m" (*(volatile uint8_t *)va)); break; } return (data); } static void pciereg_cfgwrite(int bus, unsigned slot, unsigned func, unsigned reg, int data, unsigned bytes) { vm_offset_t va; if (bus < pcie_minbus || bus > pcie_maxbus || slot > PCI_SLOTMAX || func > PCI_FUNCMAX || reg > PCIE_REGMAX) return; va = PCIE_VADDR(pcie_base, reg, bus, slot, func); switch (bytes) { case 4: __asm("movl %1, %0" : "=m" (*(volatile uint32_t *)va) : "a" (data)); break; case 2: __asm("movw %1, %0" : "=m" (*(volatile uint16_t *)va) : "a" ((uint16_t)data)); break; case 1: __asm("movb %1, %0" : "=m" (*(volatile uint8_t *)va) : "a" ((uint8_t)data)); break; } }