linux/include/asm-generic/iomap.h
Krzysztof Kozlowski 8f28ca6bd8 iomap: constify ioreadX() iomem argument (as in generic implementation)
Patch series "iomap: Constify ioreadX() iomem argument", v3.

The ioread8/16/32() and others have inconsistent interface among the
architectures: some taking address as const, some not.

It seems there is nothing really stopping all of them to take pointer to
const.

This patch (of 4):

The ioreadX() and ioreadX_rep() helpers have inconsistent interface.  On
some architectures void *__iomem address argument is a pointer to const,
on some not.

Implementations of ioreadX() do not modify the memory under the address so
they can be converted to a "const" version for const-safety and
consistency among architectures.

[krzk@kernel.org: sh: clk: fix assignment from incompatible pointer type for ioreadX()]
  Link: http://lkml.kernel.org/r/20200723082017.24053-1-krzk@kernel.org
[akpm@linux-foundation.org: fix drivers/mailbox/bcm-pdc-mailbox.c]
  Link: http://lkml.kernel.org/r/202007132209.Rxmv4QyS%25lkp@intel.com

Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Jon Mason <jdmason@kudzu.us>
Cc: Allen Hubbe <allenbh@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Link: http://lkml.kernel.org/r/20200709072837.5869-1-krzk@kernel.org
Link: http://lkml.kernel.org/r/20200709072837.5869-2-krzk@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-14 19:56:57 -07:00

117 lines
4.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __GENERIC_IO_H
#define __GENERIC_IO_H
#include <linux/linkage.h>
#include <asm/byteorder.h>
/*
* These are the "generic" interfaces for doing new-style
* memory-mapped or PIO accesses. Architectures may do
* their own arch-optimized versions, these just act as
* wrappers around the old-style IO register access functions:
* read[bwl]/write[bwl]/in[bwl]/out[bwl]
*
* Don't include this directly, include it from <asm/io.h>.
*/
/*
* Read/write from/to an (offsettable) iomem cookie. It might be a PIO
* access or a MMIO access, these functions don't care. The info is
* encoded in the hardware mapping set up by the mapping functions
* (or the cookie itself, depending on implementation and hw).
*
* The generic routines just encode the PIO/MMIO as part of the
* cookie, and coldly assume that the MMIO IO mappings are not
* in the low address range. Architectures for which this is not
* true can't use this generic implementation.
*/
extern unsigned int ioread8(const void __iomem *);
extern unsigned int ioread16(const void __iomem *);
extern unsigned int ioread16be(const void __iomem *);
extern unsigned int ioread32(const void __iomem *);
extern unsigned int ioread32be(const void __iomem *);
#ifdef CONFIG_64BIT
extern u64 ioread64(const void __iomem *);
extern u64 ioread64be(const void __iomem *);
#endif
#ifdef readq
#define ioread64_lo_hi ioread64_lo_hi
#define ioread64_hi_lo ioread64_hi_lo
#define ioread64be_lo_hi ioread64be_lo_hi
#define ioread64be_hi_lo ioread64be_hi_lo
extern u64 ioread64_lo_hi(const void __iomem *addr);
extern u64 ioread64_hi_lo(const void __iomem *addr);
extern u64 ioread64be_lo_hi(const void __iomem *addr);
extern u64 ioread64be_hi_lo(const void __iomem *addr);
#endif
extern void iowrite8(u8, void __iomem *);
extern void iowrite16(u16, void __iomem *);
extern void iowrite16be(u16, void __iomem *);
extern void iowrite32(u32, void __iomem *);
extern void iowrite32be(u32, void __iomem *);
#ifdef CONFIG_64BIT
extern void iowrite64(u64, void __iomem *);
extern void iowrite64be(u64, void __iomem *);
#endif
#ifdef writeq
#define iowrite64_lo_hi iowrite64_lo_hi
#define iowrite64_hi_lo iowrite64_hi_lo
#define iowrite64be_lo_hi iowrite64be_lo_hi
#define iowrite64be_hi_lo iowrite64be_hi_lo
extern void iowrite64_lo_hi(u64 val, void __iomem *addr);
extern void iowrite64_hi_lo(u64 val, void __iomem *addr);
extern void iowrite64be_lo_hi(u64 val, void __iomem *addr);
extern void iowrite64be_hi_lo(u64 val, void __iomem *addr);
#endif
/*
* "string" versions of the above. Note that they
* use native byte ordering for the accesses (on
* the assumption that IO and memory agree on a
* byte order, and CPU byteorder is irrelevant).
*
* They do _not_ update the port address. If you
* want MMIO that copies stuff laid out in MMIO
* memory across multiple ports, use "memcpy_toio()"
* and friends.
*/
extern void ioread8_rep(const void __iomem *port, void *buf, unsigned long count);
extern void ioread16_rep(const void __iomem *port, void *buf, unsigned long count);
extern void ioread32_rep(const void __iomem *port, void *buf, unsigned long count);
extern void iowrite8_rep(void __iomem *port, const void *buf, unsigned long count);
extern void iowrite16_rep(void __iomem *port, const void *buf, unsigned long count);
extern void iowrite32_rep(void __iomem *port, const void *buf, unsigned long count);
#ifdef CONFIG_HAS_IOPORT_MAP
/* Create a virtual mapping cookie for an IO port range */
extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
extern void ioport_unmap(void __iomem *);
#endif
#ifndef ARCH_HAS_IOREMAP_WC
#define ioremap_wc ioremap
#endif
#ifndef ARCH_HAS_IOREMAP_WT
#define ioremap_wt ioremap
#endif
#ifdef CONFIG_PCI
/* Destroy a virtual mapping cookie for a PCI BAR (memory or IO) */
struct pci_dev;
extern void pci_iounmap(struct pci_dev *dev, void __iomem *);
#elif defined(CONFIG_GENERIC_IOMAP)
struct pci_dev;
static inline void pci_iounmap(struct pci_dev *dev, void __iomem *addr)
{ }
#endif
#include <asm-generic/pci_iomap.h>
#endif