forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
222 lines
4.5 KiB
222 lines
4.5 KiB
/* SPDX-License-Identifier: GPL-2.0-only */ |
|
/* |
|
* Copyright © 2008 Keith Packard <[email protected]> |
|
*/ |
|
|
|
#ifndef _LINUX_IO_MAPPING_H |
|
#define _LINUX_IO_MAPPING_H |
|
|
|
#include <linux/types.h> |
|
#include <linux/slab.h> |
|
#include <linux/bug.h> |
|
#include <linux/io.h> |
|
#include <linux/pgtable.h> |
|
#include <asm/page.h> |
|
|
|
/* |
|
* The io_mapping mechanism provides an abstraction for mapping |
|
* individual pages from an io device to the CPU in an efficient fashion. |
|
* |
|
* See Documentation/driver-api/io-mapping.rst |
|
*/ |
|
|
|
struct io_mapping { |
|
resource_size_t base; |
|
unsigned long size; |
|
pgprot_t prot; |
|
void __iomem *iomem; |
|
}; |
|
|
|
#ifdef CONFIG_HAVE_ATOMIC_IOMAP |
|
|
|
#include <linux/pfn.h> |
|
#include <asm/iomap.h> |
|
/* |
|
* For small address space machines, mapping large objects |
|
* into the kernel virtual space isn't practical. Where |
|
* available, use fixmap support to dynamically map pages |
|
* of the object at run time. |
|
*/ |
|
|
|
static inline struct io_mapping * |
|
io_mapping_init_wc(struct io_mapping *iomap, |
|
resource_size_t base, |
|
unsigned long size) |
|
{ |
|
pgprot_t prot; |
|
|
|
if (iomap_create_wc(base, size, &prot)) |
|
return NULL; |
|
|
|
iomap->base = base; |
|
iomap->size = size; |
|
iomap->prot = prot; |
|
return iomap; |
|
} |
|
|
|
static inline void |
|
io_mapping_fini(struct io_mapping *mapping) |
|
{ |
|
iomap_free(mapping->base, mapping->size); |
|
} |
|
|
|
/* Atomic map/unmap */ |
|
static inline void __iomem * |
|
io_mapping_map_atomic_wc(struct io_mapping *mapping, |
|
unsigned long offset) |
|
{ |
|
resource_size_t phys_addr; |
|
|
|
BUG_ON(offset >= mapping->size); |
|
phys_addr = mapping->base + offset; |
|
preempt_disable(); |
|
pagefault_disable(); |
|
return __iomap_local_pfn_prot(PHYS_PFN(phys_addr), mapping->prot); |
|
} |
|
|
|
static inline void |
|
io_mapping_unmap_atomic(void __iomem *vaddr) |
|
{ |
|
kunmap_local_indexed((void __force *)vaddr); |
|
pagefault_enable(); |
|
preempt_enable(); |
|
} |
|
|
|
static inline void __iomem * |
|
io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset) |
|
{ |
|
resource_size_t phys_addr; |
|
|
|
BUG_ON(offset >= mapping->size); |
|
phys_addr = mapping->base + offset; |
|
return __iomap_local_pfn_prot(PHYS_PFN(phys_addr), mapping->prot); |
|
} |
|
|
|
static inline void io_mapping_unmap_local(void __iomem *vaddr) |
|
{ |
|
kunmap_local_indexed((void __force *)vaddr); |
|
} |
|
|
|
static inline void __iomem * |
|
io_mapping_map_wc(struct io_mapping *mapping, |
|
unsigned long offset, |
|
unsigned long size) |
|
{ |
|
resource_size_t phys_addr; |
|
|
|
BUG_ON(offset >= mapping->size); |
|
phys_addr = mapping->base + offset; |
|
|
|
return ioremap_wc(phys_addr, size); |
|
} |
|
|
|
static inline void |
|
io_mapping_unmap(void __iomem *vaddr) |
|
{ |
|
iounmap(vaddr); |
|
} |
|
|
|
#else /* HAVE_ATOMIC_IOMAP */ |
|
|
|
#include <linux/uaccess.h> |
|
|
|
/* Create the io_mapping object*/ |
|
static inline struct io_mapping * |
|
io_mapping_init_wc(struct io_mapping *iomap, |
|
resource_size_t base, |
|
unsigned long size) |
|
{ |
|
iomap->iomem = ioremap_wc(base, size); |
|
if (!iomap->iomem) |
|
return NULL; |
|
|
|
iomap->base = base; |
|
iomap->size = size; |
|
#if defined(pgprot_noncached_wc) /* archs can't agree on a name ... */ |
|
iomap->prot = pgprot_noncached_wc(PAGE_KERNEL); |
|
#elif defined(pgprot_writecombine) |
|
iomap->prot = pgprot_writecombine(PAGE_KERNEL); |
|
#else |
|
iomap->prot = pgprot_noncached(PAGE_KERNEL); |
|
#endif |
|
|
|
return iomap; |
|
} |
|
|
|
static inline void |
|
io_mapping_fini(struct io_mapping *mapping) |
|
{ |
|
iounmap(mapping->iomem); |
|
} |
|
|
|
/* Non-atomic map/unmap */ |
|
static inline void __iomem * |
|
io_mapping_map_wc(struct io_mapping *mapping, |
|
unsigned long offset, |
|
unsigned long size) |
|
{ |
|
return mapping->iomem + offset; |
|
} |
|
|
|
static inline void |
|
io_mapping_unmap(void __iomem *vaddr) |
|
{ |
|
} |
|
|
|
/* Atomic map/unmap */ |
|
static inline void __iomem * |
|
io_mapping_map_atomic_wc(struct io_mapping *mapping, |
|
unsigned long offset) |
|
{ |
|
preempt_disable(); |
|
pagefault_disable(); |
|
return io_mapping_map_wc(mapping, offset, PAGE_SIZE); |
|
} |
|
|
|
static inline void |
|
io_mapping_unmap_atomic(void __iomem *vaddr) |
|
{ |
|
io_mapping_unmap(vaddr); |
|
pagefault_enable(); |
|
preempt_enable(); |
|
} |
|
|
|
static inline void __iomem * |
|
io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset) |
|
{ |
|
return io_mapping_map_wc(mapping, offset, PAGE_SIZE); |
|
} |
|
|
|
static inline void io_mapping_unmap_local(void __iomem *vaddr) |
|
{ |
|
io_mapping_unmap(vaddr); |
|
} |
|
|
|
#endif /* !HAVE_ATOMIC_IOMAP */ |
|
|
|
static inline struct io_mapping * |
|
io_mapping_create_wc(resource_size_t base, |
|
unsigned long size) |
|
{ |
|
struct io_mapping *iomap; |
|
|
|
iomap = kmalloc(sizeof(*iomap), GFP_KERNEL); |
|
if (!iomap) |
|
return NULL; |
|
|
|
if (!io_mapping_init_wc(iomap, base, size)) { |
|
kfree(iomap); |
|
return NULL; |
|
} |
|
|
|
return iomap; |
|
} |
|
|
|
static inline void |
|
io_mapping_free(struct io_mapping *iomap) |
|
{ |
|
io_mapping_fini(iomap); |
|
kfree(iomap); |
|
} |
|
|
|
#endif /* _LINUX_IO_MAPPING_H */
|
|
|