linux/lib/iomap.c
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

386 lines
9.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Implement the default iomap interfaces
*
* (C) Copyright 2004 Linus Torvalds
*/
#include <linux/pci.h>
#include <linux/io.h>
#include <linux/export.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 don't assume any hardware mappings, and just
* encode the PIO/MMIO as part of the cookie. They 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 and should do their own copy.
*/
#ifndef HAVE_ARCH_PIO_SIZE
/*
* We encode the physical PIO addresses (0-0xffff) into the
* pointer by offsetting them with a constant (0x10000) and
* assuming that all the low addresses are always PIO. That means
* we can do some sanity checks on the low bits, and don't
* need to just take things for granted.
*/
#define PIO_OFFSET 0x10000UL
#define PIO_MASK 0x0ffffUL
#define PIO_RESERVED 0x40000UL
#endif
static void bad_io_access(unsigned long port, const char *access)
{
static int count = 10;
if (count) {
count--;
WARN(1, KERN_ERR "Bad IO access at port %#lx (%s)\n", port, access);
}
}
/*
* Ugly macros are a way of life.
*/
#define IO_COND(addr, is_pio, is_mmio) do { \
unsigned long port = (unsigned long __force)addr; \
if (port >= PIO_RESERVED) { \
is_mmio; \
} else if (port > PIO_OFFSET) { \
port &= PIO_MASK; \
is_pio; \
} else \
bad_io_access(port, #is_pio ); \
} while (0)
#ifndef pio_read16be
#define pio_read16be(port) swab16(inw(port))
#define pio_read32be(port) swab32(inl(port))
#endif
#ifndef mmio_read16be
#define mmio_read16be(addr) swab16(readw(addr))
#define mmio_read32be(addr) swab32(readl(addr))
#define mmio_read64be(addr) swab64(readq(addr))
#endif
unsigned int ioread8(const void __iomem *addr)
{
IO_COND(addr, return inb(port), return readb(addr));
return 0xff;
}
unsigned int ioread16(const void __iomem *addr)
{
IO_COND(addr, return inw(port), return readw(addr));
return 0xffff;
}
unsigned int ioread16be(const void __iomem *addr)
{
IO_COND(addr, return pio_read16be(port), return mmio_read16be(addr));
return 0xffff;
}
unsigned int ioread32(const void __iomem *addr)
{
IO_COND(addr, return inl(port), return readl(addr));
return 0xffffffff;
}
unsigned int ioread32be(const void __iomem *addr)
{
IO_COND(addr, return pio_read32be(port), return mmio_read32be(addr));
return 0xffffffff;
}
EXPORT_SYMBOL(ioread8);
EXPORT_SYMBOL(ioread16);
EXPORT_SYMBOL(ioread16be);
EXPORT_SYMBOL(ioread32);
EXPORT_SYMBOL(ioread32be);
#ifdef readq
static u64 pio_read64_lo_hi(unsigned long port)
{
u64 lo, hi;
lo = inl(port);
hi = inl(port + sizeof(u32));
return lo | (hi << 32);
}
static u64 pio_read64_hi_lo(unsigned long port)
{
u64 lo, hi;
hi = inl(port + sizeof(u32));
lo = inl(port);
return lo | (hi << 32);
}
static u64 pio_read64be_lo_hi(unsigned long port)
{
u64 lo, hi;
lo = pio_read32be(port + sizeof(u32));
hi = pio_read32be(port);
return lo | (hi << 32);
}
static u64 pio_read64be_hi_lo(unsigned long port)
{
u64 lo, hi;
hi = pio_read32be(port);
lo = pio_read32be(port + sizeof(u32));
return lo | (hi << 32);
}
u64 ioread64_lo_hi(const void __iomem *addr)
{
IO_COND(addr, return pio_read64_lo_hi(port), return readq(addr));
return 0xffffffffffffffffULL;
}
u64 ioread64_hi_lo(const void __iomem *addr)
{
IO_COND(addr, return pio_read64_hi_lo(port), return readq(addr));
return 0xffffffffffffffffULL;
}
u64 ioread64be_lo_hi(const void __iomem *addr)
{
IO_COND(addr, return pio_read64be_lo_hi(port),
return mmio_read64be(addr));
return 0xffffffffffffffffULL;
}
u64 ioread64be_hi_lo(const void __iomem *addr)
{
IO_COND(addr, return pio_read64be_hi_lo(port),
return mmio_read64be(addr));
return 0xffffffffffffffffULL;
}
EXPORT_SYMBOL(ioread64_lo_hi);
EXPORT_SYMBOL(ioread64_hi_lo);
EXPORT_SYMBOL(ioread64be_lo_hi);
EXPORT_SYMBOL(ioread64be_hi_lo);
#endif /* readq */
#ifndef pio_write16be
#define pio_write16be(val,port) outw(swab16(val),port)
#define pio_write32be(val,port) outl(swab32(val),port)
#endif
#ifndef mmio_write16be
#define mmio_write16be(val,port) writew(swab16(val),port)
#define mmio_write32be(val,port) writel(swab32(val),port)
#define mmio_write64be(val,port) writeq(swab64(val),port)
#endif
void iowrite8(u8 val, void __iomem *addr)
{
IO_COND(addr, outb(val,port), writeb(val, addr));
}
void iowrite16(u16 val, void __iomem *addr)
{
IO_COND(addr, outw(val,port), writew(val, addr));
}
void iowrite16be(u16 val, void __iomem *addr)
{
IO_COND(addr, pio_write16be(val,port), mmio_write16be(val, addr));
}
void iowrite32(u32 val, void __iomem *addr)
{
IO_COND(addr, outl(val,port), writel(val, addr));
}
void iowrite32be(u32 val, void __iomem *addr)
{
IO_COND(addr, pio_write32be(val,port), mmio_write32be(val, addr));
}
EXPORT_SYMBOL(iowrite8);
EXPORT_SYMBOL(iowrite16);
EXPORT_SYMBOL(iowrite16be);
EXPORT_SYMBOL(iowrite32);
EXPORT_SYMBOL(iowrite32be);
#ifdef writeq
static void pio_write64_lo_hi(u64 val, unsigned long port)
{
outl(val, port);
outl(val >> 32, port + sizeof(u32));
}
static void pio_write64_hi_lo(u64 val, unsigned long port)
{
outl(val >> 32, port + sizeof(u32));
outl(val, port);
}
static void pio_write64be_lo_hi(u64 val, unsigned long port)
{
pio_write32be(val, port + sizeof(u32));
pio_write32be(val >> 32, port);
}
static void pio_write64be_hi_lo(u64 val, unsigned long port)
{
pio_write32be(val >> 32, port);
pio_write32be(val, port + sizeof(u32));
}
void iowrite64_lo_hi(u64 val, void __iomem *addr)
{
IO_COND(addr, pio_write64_lo_hi(val, port),
writeq(val, addr));
}
void iowrite64_hi_lo(u64 val, void __iomem *addr)
{
IO_COND(addr, pio_write64_hi_lo(val, port),
writeq(val, addr));
}
void iowrite64be_lo_hi(u64 val, void __iomem *addr)
{
IO_COND(addr, pio_write64be_lo_hi(val, port),
mmio_write64be(val, addr));
}
void iowrite64be_hi_lo(u64 val, void __iomem *addr)
{
IO_COND(addr, pio_write64be_hi_lo(val, port),
mmio_write64be(val, addr));
}
EXPORT_SYMBOL(iowrite64_lo_hi);
EXPORT_SYMBOL(iowrite64_hi_lo);
EXPORT_SYMBOL(iowrite64be_lo_hi);
EXPORT_SYMBOL(iowrite64be_hi_lo);
#endif /* readq */
/*
* These are the "repeat MMIO read/write" functions.
* Note the "__raw" accesses, since we don't want to
* convert to CPU byte order. We write in "IO byte
* order" (we also don't have IO barriers).
*/
#ifndef mmio_insb
static inline void mmio_insb(const void __iomem *addr, u8 *dst, int count)
{
while (--count >= 0) {
u8 data = __raw_readb(addr);
*dst = data;
dst++;
}
}
static inline void mmio_insw(const void __iomem *addr, u16 *dst, int count)
{
while (--count >= 0) {
u16 data = __raw_readw(addr);
*dst = data;
dst++;
}
}
static inline void mmio_insl(const void __iomem *addr, u32 *dst, int count)
{
while (--count >= 0) {
u32 data = __raw_readl(addr);
*dst = data;
dst++;
}
}
#endif
#ifndef mmio_outsb
static inline void mmio_outsb(void __iomem *addr, const u8 *src, int count)
{
while (--count >= 0) {
__raw_writeb(*src, addr);
src++;
}
}
static inline void mmio_outsw(void __iomem *addr, const u16 *src, int count)
{
while (--count >= 0) {
__raw_writew(*src, addr);
src++;
}
}
static inline void mmio_outsl(void __iomem *addr, const u32 *src, int count)
{
while (--count >= 0) {
__raw_writel(*src, addr);
src++;
}
}
#endif
void ioread8_rep(const void __iomem *addr, void *dst, unsigned long count)
{
IO_COND(addr, insb(port,dst,count), mmio_insb(addr, dst, count));
}
void ioread16_rep(const void __iomem *addr, void *dst, unsigned long count)
{
IO_COND(addr, insw(port,dst,count), mmio_insw(addr, dst, count));
}
void ioread32_rep(const void __iomem *addr, void *dst, unsigned long count)
{
IO_COND(addr, insl(port,dst,count), mmio_insl(addr, dst, count));
}
EXPORT_SYMBOL(ioread8_rep);
EXPORT_SYMBOL(ioread16_rep);
EXPORT_SYMBOL(ioread32_rep);
void iowrite8_rep(void __iomem *addr, const void *src, unsigned long count)
{
IO_COND(addr, outsb(port, src, count), mmio_outsb(addr, src, count));
}
void iowrite16_rep(void __iomem *addr, const void *src, unsigned long count)
{
IO_COND(addr, outsw(port, src, count), mmio_outsw(addr, src, count));
}
void iowrite32_rep(void __iomem *addr, const void *src, unsigned long count)
{
IO_COND(addr, outsl(port, src,count), mmio_outsl(addr, src, count));
}
EXPORT_SYMBOL(iowrite8_rep);
EXPORT_SYMBOL(iowrite16_rep);
EXPORT_SYMBOL(iowrite32_rep);
#ifdef CONFIG_HAS_IOPORT_MAP
/* Create a virtual mapping cookie for an IO port range */
void __iomem *ioport_map(unsigned long port, unsigned int nr)
{
if (port > PIO_MASK)
return NULL;
return (void __iomem *) (unsigned long) (port + PIO_OFFSET);
}
void ioport_unmap(void __iomem *addr)
{
/* Nothing to do */
}
EXPORT_SYMBOL(ioport_map);
EXPORT_SYMBOL(ioport_unmap);
#endif /* CONFIG_HAS_IOPORT_MAP */
#ifdef CONFIG_PCI
/* Hide the details if this is a MMIO or PIO address space and just do what
* you expect in the correct way. */
void pci_iounmap(struct pci_dev *dev, void __iomem * addr)
{
IO_COND(addr, /* nothing */, iounmap(addr));
}
EXPORT_SYMBOL(pci_iounmap);
#endif /* CONFIG_PCI */