cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

pci_iomap.c (5823B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * Implement the default iomap interfaces
      4 *
      5 * (C) Copyright 2004 Linus Torvalds
      6 */
      7#include <linux/pci.h>
      8#include <linux/io.h>
      9
     10#include <linux/export.h>
     11
     12#ifdef CONFIG_PCI
     13/**
     14 * pci_iomap_range - create a virtual mapping cookie for a PCI BAR
     15 * @dev: PCI device that owns the BAR
     16 * @bar: BAR number
     17 * @offset: map memory at the given offset in BAR
     18 * @maxlen: max length of the memory to map
     19 *
     20 * Using this function you will get a __iomem address to your device BAR.
     21 * You can access it using ioread*() and iowrite*(). These functions hide
     22 * the details if this is a MMIO or PIO address space and will just do what
     23 * you expect from them in the correct way.
     24 *
     25 * @maxlen specifies the maximum length to map. If you want to get access to
     26 * the complete BAR from offset to the end, pass %0 here.
     27 * */
     28void __iomem *pci_iomap_range(struct pci_dev *dev,
     29			      int bar,
     30			      unsigned long offset,
     31			      unsigned long maxlen)
     32{
     33	resource_size_t start = pci_resource_start(dev, bar);
     34	resource_size_t len = pci_resource_len(dev, bar);
     35	unsigned long flags = pci_resource_flags(dev, bar);
     36
     37	if (len <= offset || !start)
     38		return NULL;
     39	len -= offset;
     40	start += offset;
     41	if (maxlen && len > maxlen)
     42		len = maxlen;
     43	if (flags & IORESOURCE_IO)
     44		return __pci_ioport_map(dev, start, len);
     45	if (flags & IORESOURCE_MEM)
     46		return ioremap(start, len);
     47	/* What? */
     48	return NULL;
     49}
     50EXPORT_SYMBOL(pci_iomap_range);
     51
     52/**
     53 * pci_iomap_wc_range - create a virtual WC mapping cookie for a PCI BAR
     54 * @dev: PCI device that owns the BAR
     55 * @bar: BAR number
     56 * @offset: map memory at the given offset in BAR
     57 * @maxlen: max length of the memory to map
     58 *
     59 * Using this function you will get a __iomem address to your device BAR.
     60 * You can access it using ioread*() and iowrite*(). These functions hide
     61 * the details if this is a MMIO or PIO address space and will just do what
     62 * you expect from them in the correct way. When possible write combining
     63 * is used.
     64 *
     65 * @maxlen specifies the maximum length to map. If you want to get access to
     66 * the complete BAR from offset to the end, pass %0 here.
     67 * */
     68void __iomem *pci_iomap_wc_range(struct pci_dev *dev,
     69				 int bar,
     70				 unsigned long offset,
     71				 unsigned long maxlen)
     72{
     73	resource_size_t start = pci_resource_start(dev, bar);
     74	resource_size_t len = pci_resource_len(dev, bar);
     75	unsigned long flags = pci_resource_flags(dev, bar);
     76
     77
     78	if (flags & IORESOURCE_IO)
     79		return NULL;
     80
     81	if (len <= offset || !start)
     82		return NULL;
     83
     84	len -= offset;
     85	start += offset;
     86	if (maxlen && len > maxlen)
     87		len = maxlen;
     88
     89	if (flags & IORESOURCE_MEM)
     90		return ioremap_wc(start, len);
     91
     92	/* What? */
     93	return NULL;
     94}
     95EXPORT_SYMBOL_GPL(pci_iomap_wc_range);
     96
     97/**
     98 * pci_iomap - create a virtual mapping cookie for a PCI BAR
     99 * @dev: PCI device that owns the BAR
    100 * @bar: BAR number
    101 * @maxlen: length of the memory to map
    102 *
    103 * Using this function you will get a __iomem address to your device BAR.
    104 * You can access it using ioread*() and iowrite*(). These functions hide
    105 * the details if this is a MMIO or PIO address space and will just do what
    106 * you expect from them in the correct way.
    107 *
    108 * @maxlen specifies the maximum length to map. If you want to get access to
    109 * the complete BAR without checking for its length first, pass %0 here.
    110 * */
    111void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
    112{
    113	return pci_iomap_range(dev, bar, 0, maxlen);
    114}
    115EXPORT_SYMBOL(pci_iomap);
    116
    117/**
    118 * pci_iomap_wc - create a virtual WC mapping cookie for a PCI BAR
    119 * @dev: PCI device that owns the BAR
    120 * @bar: BAR number
    121 * @maxlen: length of the memory to map
    122 *
    123 * Using this function you will get a __iomem address to your device BAR.
    124 * You can access it using ioread*() and iowrite*(). These functions hide
    125 * the details if this is a MMIO or PIO address space and will just do what
    126 * you expect from them in the correct way. When possible write combining
    127 * is used.
    128 *
    129 * @maxlen specifies the maximum length to map. If you want to get access to
    130 * the complete BAR without checking for its length first, pass %0 here.
    131 * */
    132void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long maxlen)
    133{
    134	return pci_iomap_wc_range(dev, bar, 0, maxlen);
    135}
    136EXPORT_SYMBOL_GPL(pci_iomap_wc);
    137
    138/*
    139 * pci_iounmap() somewhat illogically comes from lib/iomap.c for the
    140 * CONFIG_GENERIC_IOMAP case, because that's the code that knows about
    141 * the different IOMAP ranges.
    142 *
    143 * But if the architecture does not use the generic iomap code, and if
    144 * it has _not_ defined it's own private pci_iounmap function, we define
    145 * it here.
    146 *
    147 * NOTE! This default implementation assumes that if the architecture
    148 * support ioport mapping (HAS_IOPORT_MAP), the ioport mapping will
    149 * be fixed to the range [ PCI_IOBASE, PCI_IOBASE+IO_SPACE_LIMIT [,
    150 * and does not need unmapping with 'ioport_unmap()'.
    151 *
    152 * If you have different rules for your architecture, you need to
    153 * implement your own pci_iounmap() that knows the rules for where
    154 * and how IO vs MEM get mapped.
    155 *
    156 * This code is odd, and the ARCH_HAS/ARCH_WANTS #define logic comes
    157 * from legacy <asm-generic/io.h> header file behavior. In particular,
    158 * it would seem to make sense to do the iounmap(p) for the non-IO-space
    159 * case here regardless, but that's not what the old header file code
    160 * did. Probably incorrectly, but this is meant to be bug-for-bug
    161 * compatible.
    162 */
    163#if defined(ARCH_WANTS_GENERIC_PCI_IOUNMAP)
    164
    165void pci_iounmap(struct pci_dev *dev, void __iomem *p)
    166{
    167#ifdef ARCH_HAS_GENERIC_IOPORT_MAP
    168	uintptr_t start = (uintptr_t) PCI_IOBASE;
    169	uintptr_t addr = (uintptr_t) p;
    170
    171	if (addr >= start && addr < start + IO_SPACE_LIMIT)
    172		return;
    173	iounmap(p);
    174#endif
    175}
    176EXPORT_SYMBOL(pci_iounmap);
    177
    178#endif /* ARCH_WANTS_GENERIC_PCI_IOUNMAP */
    179
    180#endif /* CONFIG_PCI */