// SPDX-License-Identifier: GPL-2.0
/*
* Implement the default iomap interfaces
*
* (C) Copyright 2004 Linus Torvalds
*/
#include <linux/pci.h>
#include <linux/io.h>
#include <linux/export.h>
/**
* pci_iomap_range - create a virtual mapping cookie for a PCI BAR
* @dev: PCI device that owns the BAR
* @bar: BAR number
* @offset: map memory at the given offset in BAR
* @maxlen: max length of the memory to map
*
* Using this function you will get a __iomem address to your device BAR.
* You can access it using ioread*() and iowrite*(). These functions hide
* the details if this is a MMIO or PIO address space and will just do what
* you expect from them in the correct way.
*
* @maxlen specifies the maximum length to map. If you want to get access to
* the complete BAR from offset to the end, pass %0 here.
*
* NOTE:
* This function is never managed, even if you initialized with
* pcim_enable_device().
* */
void __iomem *pci_iomap_range(struct pci_dev *dev,
int bar,
unsigned long offset,
unsigned long maxlen)
{
resource_size_t start = pci_resource_start(dev, bar);
resource_size_t len = pci_resource_len(dev, bar);
unsigned long flags = pci_resource_flags(dev, bar);
if (len <= offset || !start)
return NULL;
len -= offset;
start += offset;
if (maxlen && len > maxlen)
len = maxlen;
if (flags & IORESOURCE_IO)
return __pci_ioport_map(dev, start, len);
if (flags & IORESOURCE_MEM)
return ioremap(start, len);
/* What? */
return NULL;
}
EXPORT_SYMBOL(pci_iomap_range);
/**
* pci_iomap_wc_range - create a virtual WC mapping cookie for a PCI BAR
* @dev: PCI device that owns the BAR
* @bar: BAR number
* @offset: map memory at the given offset in BAR
* @maxlen: max length of the memory to map
*
* Using this function you will get a __iomem address to your device BAR.
* You can access it using ioread*() and iowrite*(). These functions hide
* the details if this is a MMIO or PIO address space and will just do what
* you expect from them in the correct way. When possible write combining
* is used.
*
* @maxlen specifies the maximum length to map. If you want to get access to
* the complete BAR from offset to the end, pass %0 here.
*
* NOTE:
* This function is never managed, even if you initialized with
* pcim_enable_device().
* */
void __iomem *pci_iomap_wc_range(struct pci_dev *dev,
int bar,
unsigned long offset,
unsigned long maxlen)
{
resource_size_t start = pci_resource_start(dev, bar);
resource_size_t len = pci_resource_len(dev, bar);
unsigned long flags = pci_resource_flags(dev, bar);
if (flags & IORESOURCE_IO)
return NULL;
if (len <= offset || !start)
return NULL;
len -= offset;
start += offset;
if (maxlen && len > maxlen)
len = maxlen;
if (flags & IORESOURCE_MEM)
return ioremap_wc(start, len);
/* What? */
return NULL;
}
EXPORT_SYMBOL_GPL(pci_iomap_wc_range);
/**
* pci_iomap - create a virtual mapping cookie for a PCI BAR
* @dev: PCI device that owns the BAR
* @bar: BAR number
* @maxlen: length of the memory to map
*
* Using this function you will get a __iomem address to your device BAR.
* You can access it using ioread*() and iowrite*(). These functions hide
* the details if this is a MMIO or PIO address space and will just do what
* you expect from them in the correct way.
*
* @maxlen specifies the maximum length to map. If you want to get access to
* the complete BAR without checking for its length first, pass %0 here.
*
* NOTE:
* This function is never managed, even if you initialized with
* pcim_enable_device(). If you need automatic cleanup, use pcim_iomap().
* */
void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
{
return pci_iomap_range(dev, bar, 0, maxlen);
}
EXPORT_SYMBOL(pci_iomap);
/**
* pci_iomap_wc - create a virtual WC mapping cookie for a PCI BAR
* @dev: PCI device that owns the BAR
* @bar: BAR number
* @maxlen: length of the memory to map
*
* Using this function you will get a __iomem address to your device BAR.
* You can access it using ioread*() and iowrite*(). These functions hide
* the details if this is a MMIO or PIO address space and will just do what
* you expect from them in the correct way. When possible write combining
* is used.
*
* @maxlen specifies the maximum length to map. If you want to get access to
* the complete BAR without checking for its length first, pass %0 here.
*
* NOTE:
* This function is never managed, even if you initialized with
* pcim_enable_device().
* */
void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long maxlen)
{
return pci_iomap_wc_range(dev, bar, 0, maxlen);
}
EXPORT_SYMBOL_GPL(pci_iomap_wc);
/*
* pci_iounmap() somewhat illogically comes from lib/iomap.c for the
* CONFIG_GENERIC_IOMAP case, because that's the code that knows about
* the different IOMAP ranges.
*
* But if the architecture does not use the generic iomap code, and if
* it has _not_ defined its own private pci_iounmap function, we define
* it here.
*
* NOTE! This default implementation assumes that if the architecture
* support ioport mapping (HAS_IOPORT_MAP), the ioport mapping will
* be fixed to the range [ PCI_IOBASE, PCI_IOBASE+IO_SPACE_LIMIT [,
* and does not need unmapping with 'ioport_unmap()'.
*
* If you have different rules for your architecture, you need to
* implement your own pci_iounmap() that knows the rules for where
* and how IO vs MEM get mapped.
*
* This code is odd, and the ARCH_HAS/ARCH_WANTS #define logic comes
* from legacy <asm-generic/io.h> header file behavior. In particular,
* it would seem to make sense to do the iounmap(p) for the non-IO-space
* case here regardless, but that's not what the old header file code
* did. Probably incorrectly, but this is meant to be bug-for-bug
* compatible.
*/
#if defined(ARCH_WANTS_GENERIC_PCI_IOUNMAP)
void pci_iounmap(struct pci_dev *dev, void __iomem *p)
{
#ifdef ARCH_HAS_GENERIC_IOPORT_MAP
uintptr_t start = (uintptr_t) PCI_IOBASE;
uintptr_t addr = (uintptr_t) p;
if (addr >= start && addr < start + IO_SPACE_LIMIT)
return;
#endif
iounmap(p);
}
EXPORT_SYMBOL(pci_iounmap);
#endif /* ARCH_WANTS_GENERIC_PCI_IOUNMAP */
Codebase Browser
linux