linux/arch/ia64/mm/ioremap.c
Mauro Carvalho Chehab db9a0975a2 docs: ia64: convert to ReST
Rename the ia64 documentation files to ReST, add an
index for them and adjust in order to produce a nice html
output via the Sphinx build system.

There are two upper case file names. Rename them to
lower case, as we're working to avoid upper case file
names at Documentation.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15 09:20:25 -03:00

123 lines
3.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* (c) Copyright 2006, 2007 Hewlett-Packard Development Company, L.P.
* Bjorn Helgaas <bjorn.helgaas@hp.com>
*/
#include <linux/compiler.h>
#include <linux/module.h>
#include <linux/efi.h>
#include <linux/io.h>
#include <linux/vmalloc.h>
#include <asm/io.h>
#include <asm/meminit.h>
static inline void __iomem *
__ioremap_uc(unsigned long phys_addr)
{
return (void __iomem *) (__IA64_UNCACHED_OFFSET | phys_addr);
}
void __iomem *
early_ioremap (unsigned long phys_addr, unsigned long size)
{
u64 attr;
attr = kern_mem_attribute(phys_addr, size);
if (attr & EFI_MEMORY_WB)
return (void __iomem *) phys_to_virt(phys_addr);
return __ioremap_uc(phys_addr);
}
void __iomem *
ioremap (unsigned long phys_addr, unsigned long size)
{
void __iomem *addr;
struct vm_struct *area;
unsigned long offset;
pgprot_t prot;
u64 attr;
unsigned long gran_base, gran_size;
unsigned long page_base;
/*
* For things in kern_memmap, we must use the same attribute
* as the rest of the kernel. For more details, see
* Documentation/ia64/aliasing.rst.
*/
attr = kern_mem_attribute(phys_addr, size);
if (attr & EFI_MEMORY_WB)
return (void __iomem *) phys_to_virt(phys_addr);
else if (attr & EFI_MEMORY_UC)
return __ioremap_uc(phys_addr);
/*
* Some chipsets don't support UC access to memory. If
* WB is supported for the whole granule, we prefer that.
*/
gran_base = GRANULEROUNDDOWN(phys_addr);
gran_size = GRANULEROUNDUP(phys_addr + size) - gran_base;
if (efi_mem_attribute(gran_base, gran_size) & EFI_MEMORY_WB)
return (void __iomem *) phys_to_virt(phys_addr);
/*
* WB is not supported for the whole granule, so we can't use
* the region 7 identity mapping. If we can safely cover the
* area with kernel page table mappings, we can use those
* instead.
*/
page_base = phys_addr & PAGE_MASK;
size = PAGE_ALIGN(phys_addr + size) - page_base;
if (efi_mem_attribute(page_base, size) & EFI_MEMORY_WB) {
prot = PAGE_KERNEL;
/*
* Mappings have to be page-aligned
*/
offset = phys_addr & ~PAGE_MASK;
phys_addr &= PAGE_MASK;
/*
* Ok, go for it..
*/
area = get_vm_area(size, VM_IOREMAP);
if (!area)
return NULL;
area->phys_addr = phys_addr;
addr = (void __iomem *) area->addr;
if (ioremap_page_range((unsigned long) addr,
(unsigned long) addr + size, phys_addr, prot)) {
vunmap((void __force *) addr);
return NULL;
}
return (void __iomem *) (offset + (char __iomem *)addr);
}
return __ioremap_uc(phys_addr);
}
EXPORT_SYMBOL(ioremap);
void __iomem *
ioremap_nocache (unsigned long phys_addr, unsigned long size)
{
if (kern_mem_attribute(phys_addr, size) & EFI_MEMORY_WB)
return NULL;
return __ioremap_uc(phys_addr);
}
EXPORT_SYMBOL(ioremap_nocache);
void
early_iounmap (volatile void __iomem *addr, unsigned long size)
{
}
void
iounmap (volatile void __iomem *addr)
{
if (REGION_NUMBER(addr) == RGN_GATE)
vunmap((void *) ((unsigned long) addr & PAGE_MASK));
}
EXPORT_SYMBOL(iounmap);