From 9d4ae7276ae26c5bfba6207cf05340af1931d8d4 Mon Sep 17 00:00:00 2001
From: Deepak Saxena <dsaxena@plexity.net>
Date: Mon, 9 Jan 2006 19:23:11 +0000
Subject: [PATCH] [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>
---
arch/arm/mm/ioremap.c | 49 ++++++++++++++++++++++----------------
include/asm-arm/io.h | 6 +++++
include/asm-arm/mach/map.h | 3 ---
include/asm-arm/memory.h | 6 +++++
4 files changed, 41 insertions(+), 23 deletions(-)
diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index 10901398e4a2..de3ce1eec2ec 100644
--- a/arch/arm/mm/ioremap.c
+++ b/arch/arm/mm/ioremap.c
@@ -86,11 +86,12 @@ remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
}
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;
@@ -129,37 +130,45 @@ remap_area_pages(unsigned long start, unsigned long phys_addr,
* 'flags' are the extra L_PTE_ flags that you want to specify for this
* 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);
diff --git a/include/asm-arm/io.h b/include/asm-arm/io.h
index 0cf4d4f99600..fd0147e52dbb 100644
--- a/include/asm-arm/io.h
+++ b/include/asm-arm/io.h
@@ -56,7 +56,12 @@ extern void __raw_readsl(const void __iomem *addr, void *data, int longlen);
/*
* Architecture ioremap implementation.
+ *
+ * __ioremap takes CPU physical address.
+ *
+ * __ioremap_pfn takes a Page Frame Number and an offset into that page
*/
+extern void __iomem * __ioremap_pfn(unsigned long, unsigned long, size_t, unsigned long);
extern void __iomem * __ioremap(unsigned long, size_t, unsigned long);
extern void __iounmap(void __iomem *addr);
@@ -261,6 +266,7 @@ out:
*
* ioremap takes a PCI memory address, as specified in
* Documentation/IO-mapping.txt.
+ *
*/
#ifndef __arch_ioremap
#define ioremap(cookie,size) __ioremap(cookie,size,0)
diff --git a/include/asm-arm/mach/map.h b/include/asm-arm/mach/map.h
index b338936bde4f..3351b77fab36 100644
--- a/include/asm-arm/mach/map.h
+++ b/include/asm-arm/mach/map.h
@@ -27,9 +27,6 @@ struct meminfo;
#define MT_ROM 6
#define MT_IXP2000_DEVICE 7
-#define __phys_to_pfn(paddr) ((paddr) >> PAGE_SHIFT)
-#define __pfn_to_phys(pfn) ((pfn) << PAGE_SHIFT)
-
extern void create_memmap_holes(struct meminfo *);
extern void memtable_init(struct meminfo *);
extern void iotable_init(struct map_desc *, int);
diff --git a/include/asm-arm/memory.h b/include/asm-arm/memory.h
index 3e572364ee73..3d7f08bd9030 100644
--- a/include/asm-arm/memory.h
+++ b/include/asm-arm/memory.h
@@ -57,6 +57,12 @@
#define __phys_to_virt(x) ((x) - PHYS_OFFSET + PAGE_OFFSET)
#endif
+/*
+ * Convert a physical address to a Page Frame Number and back
+ */
+#define __phys_to_pfn(paddr) ((paddr) >> PAGE_SHIFT)
+#define __pfn_to_phys(pfn) ((pfn) << PAGE_SHIFT)
+
/*
* The module space lives between the addresses given by TASK_SIZE
* and PAGE_OFFSET - it must be within 32MB of the kernel text.