/* * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Numascale NumaConnect-specific PCI code * * Copyright (C) 2012 Numascale AS. All rights reserved. * * Send feedback to <support@numascale.com> * * PCI accessor functions derived from mmconfig_64.c * */ #include <linux/pci.h> #include <asm/pci_x86.h> static u8 limit __read_mostly; static inline char __iomem *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn) { struct pci_mmcfg_region *cfg = pci_mmconfig_lookup(seg, bus); if (cfg && cfg->virt) return cfg->virt + (PCI_MMCFG_BUS_OFFSET(bus) | (devfn << 12)); return NULL; } static int pci_mmcfg_read_numachip(unsigned int seg, unsigned int bus, unsigned int devfn, int reg, int len, u32 *value) { char __iomem *addr; /* Why do we have this when nobody checks it. How about a BUG()!? -AK */ if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) { err: *value = -1; return -EINVAL; } /* Ensure AMD Northbridges don't decode reads to other devices */ if (unlikely(bus == 0 && devfn >= limit)) { *value = -1; return 0; } rcu_read_lock(); addr = pci_dev_base(seg, bus, devfn); if (!addr) { rcu_read_unlock(); goto err; } switch (len) { case 1: *value = mmio_config_readb(addr + reg); break; case 2: *value = mmio_config_readw(addr + reg); break; case 4: *value = mmio_config_readl(addr + reg); break; } rcu_read_unlock(); return 0; } static int pci_mmcfg_write_numachip(unsigned int seg, unsigned int bus, unsigned int devfn, int reg, int len, u32 value) { char __iomem *addr; /* Why do we have this when nobody checks it. How about a BUG()!? -AK */ if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) return -EINVAL; /* Ensure AMD Northbridges don't decode writes to other devices */ if (unlikely(bus == 0 && devfn >= limit)) return 0; rcu_read_lock(); addr = pci_dev_base(seg, bus, devfn); if (!addr) { rcu_read_unlock(); return -EINVAL; } switch (len) { case 1: mmio_config_writeb(addr + reg, value); break; case 2: mmio_config_writew(addr + reg, value); break; case 4: mmio_config_writel(addr + reg, value); break; } rcu_read_unlock(); return 0; } static const struct pci_raw_ops pci_mmcfg_numachip = { .read = pci_mmcfg_read_numachip, .write = pci_mmcfg_write_numachip, }; int __init pci_numachip_init(void) { int ret = 0; u32 val; /* For remote I/O, restrict bus 0 access to the actual number of AMD Northbridges, which starts at device number 0x18 */ ret = raw_pci_read(0, 0, PCI_DEVFN(0x18, 0), 0x60, sizeof(val), &val); if (ret) goto out; /* HyperTransport fabric size in bits 6:4 */ limit = PCI_DEVFN(0x18 + ((val >> 4) & 7) + 1, 0); /* Use NumaChip PCI accessors for non-extended and extended access */ raw_pci_ops = raw_pci_ext_ops = &pci_mmcfg_numachip; out: return ret; }