diff options
author | Tomasz Nowicki <tn@semihalf.com> | 2016-05-11 22:34:51 (GMT) |
---|---|---|
committer | Bjorn Helgaas <bhelgaas@google.com> | 2016-05-12 12:07:42 (GMT) |
commit | c5076cfe768998e9d395bc8486b29b18b0f99fd9 (patch) | |
tree | 94eaff672e0871147c33abf16edcbf0843078e25 /drivers/pci/pci.c | |
parent | 1958e7173df14ff50d75ed2fbd24b349d25caf80 (diff) | |
download | linux-c5076cfe768998e9d395bc8486b29b18b0f99fd9.tar.xz |
PCI, of: Move PCI I/O space management to PCI core code
No functional changes in this patch.
PCI I/O space mapping code does not depend on OF; therefore it can be moved
to PCI core code. This way we will be able to use it, e.g., in ACPI PCI
code.
Suggested-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Tomasz Nowicki <tn@semihalf.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Arnd Bergmann <arnd@arndb.de>
CC: Liviu Dudau <Liviu.Dudau@arm.com>
Diffstat (limited to 'drivers/pci/pci.c')
-rw-r--r-- | drivers/pci/pci.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 25e0327..bc0c914 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -3021,6 +3021,121 @@ int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name) } EXPORT_SYMBOL(pci_request_regions_exclusive); +#ifdef PCI_IOBASE +struct io_range { + struct list_head list; + phys_addr_t start; + resource_size_t size; +}; + +static LIST_HEAD(io_range_list); +static DEFINE_SPINLOCK(io_range_lock); +#endif + +/* + * Record the PCI IO range (expressed as CPU physical address + size). + * Return a negative value if an error has occured, zero otherwise + */ +int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size) +{ + int err = 0; + +#ifdef PCI_IOBASE + struct io_range *range; + resource_size_t allocated_size = 0; + + /* check if the range hasn't been previously recorded */ + spin_lock(&io_range_lock); + list_for_each_entry(range, &io_range_list, list) { + if (addr >= range->start && addr + size <= range->start + size) { + /* range already registered, bail out */ + goto end_register; + } + allocated_size += range->size; + } + + /* range not registed yet, check for available space */ + if (allocated_size + size - 1 > IO_SPACE_LIMIT) { + /* if it's too big check if 64K space can be reserved */ + if (allocated_size + SZ_64K - 1 > IO_SPACE_LIMIT) { + err = -E2BIG; + goto end_register; + } + + size = SZ_64K; + pr_warn("Requested IO range too big, new size set to 64K\n"); + } + + /* add the range to the list */ + range = kzalloc(sizeof(*range), GFP_ATOMIC); + if (!range) { + err = -ENOMEM; + goto end_register; + } + + range->start = addr; + range->size = size; + + list_add_tail(&range->list, &io_range_list); + +end_register: + spin_unlock(&io_range_lock); +#endif + + return err; +} + +phys_addr_t pci_pio_to_address(unsigned long pio) +{ + phys_addr_t address = (phys_addr_t)OF_BAD_ADDR; + +#ifdef PCI_IOBASE + struct io_range *range; + resource_size_t allocated_size = 0; + + if (pio > IO_SPACE_LIMIT) + return address; + + spin_lock(&io_range_lock); + list_for_each_entry(range, &io_range_list, list) { + if (pio >= allocated_size && pio < allocated_size + range->size) { + address = range->start + pio - allocated_size; + break; + } + allocated_size += range->size; + } + spin_unlock(&io_range_lock); +#endif + + return address; +} + +unsigned long __weak pci_address_to_pio(phys_addr_t address) +{ +#ifdef PCI_IOBASE + struct io_range *res; + resource_size_t offset = 0; + unsigned long addr = -1; + + spin_lock(&io_range_lock); + list_for_each_entry(res, &io_range_list, list) { + if (address >= res->start && address < res->start + res->size) { + addr = address - res->start + offset; + break; + } + offset += res->size; + } + spin_unlock(&io_range_lock); + + return addr; +#else + if (address > IO_SPACE_LIMIT) + return (unsigned long)-1; + + return (unsigned long) address; +#endif +} + /** * pci_remap_iospace - Remap the memory mapped I/O space * @res: Resource describing the I/O space |