[ARM] 3070/2: Add __ioremap_pfn() API
Patch from Deepak Saxena
In working on adding 36-bit addressed supersection support to ioremap(),
I came to the conclusion that it would be far simpler to do so by just
splitting __ioremap() into a main external interface and adding an
__ioremap_pfn() function that takes a pfn + offset into the page that
__ioremap() can call. This way existing callers of __ioremap() won't have
to change their code and 36-bit systems will just call __ioremap_pfn()
and we will not have to deal with unsigned long long variables.
Note that __ioremap_pfn() should _NOT_ be called directly by drivers
but is reserved for use by arch_ioremap() implementations that map
32-bit resource regions into the real 36-bit address and then call
this new function.
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index 1090139..de3ce1e 100644
--- a/arch/arm/mm/ioremap.c
+++ b/arch/arm/mm/ioremap.c
@@ -86,11 +86,12 @@
}
static int
-remap_area_pages(unsigned long start, unsigned long phys_addr,
+remap_area_pages(unsigned long start, unsigned long pfn,
unsigned long size, unsigned long flags)
{
unsigned long address = start;
unsigned long end = start + size;
+ unsigned long phys_addr = __pfn_to_phys(pfn);
int err = 0;
pgd_t * dir;
@@ -130,36 +131,44 @@
* mapping. See include/asm-arm/proc-armv/pgtable.h for more information.
*/
void __iomem *
+__ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
+ unsigned long flags)
+{
+ unsigned long addr;
+ struct vm_struct * area;
+
+ area = get_vm_area(size, VM_IOREMAP);
+ if (!area)
+ return NULL;
+ addr = (unsigned long)area->addr;
+ if (remap_area_pages(addr, pfn, size, flags)) {
+ vfree(addr);
+ return NULL;
+ }
+ return (void __iomem *) (offset + (char *)addr);
+}
+EXPORT_SYMBOL(__ioremap_pfn);
+
+void __iomem *
__ioremap(unsigned long phys_addr, size_t size, unsigned long flags)
{
- void * addr;
- struct vm_struct * area;
- unsigned long offset, last_addr;
+ unsigned long last_addr;
+ unsigned long offset = phys_addr & ~PAGE_MASK;
+ unsigned long pfn = __phys_to_pfn(phys_addr);
- /* Don't allow wraparound or zero size */
+ /*
+ * Don't allow wraparound or zero size
+ */
last_addr = phys_addr + size - 1;
if (!size || last_addr < phys_addr)
return NULL;
/*
- * Mappings have to be page-aligned
+ * Page align the mapping size
*/
- offset = phys_addr & ~PAGE_MASK;
- phys_addr &= PAGE_MASK;
size = PAGE_ALIGN(last_addr + 1) - phys_addr;
- /*
- * Ok, go for it..
- */
- area = get_vm_area(size, VM_IOREMAP);
- if (!area)
- return NULL;
- addr = area->addr;
- if (remap_area_pages((unsigned long) addr, phys_addr, size, flags)) {
- vfree(addr);
- return NULL;
- }
- return (void __iomem *) (offset + (char *)addr);
+ return __ioremap_pfn(pfn, offset, size, flags);
}
EXPORT_SYMBOL(__ioremap);