linux/arch/powerpc/mm/ioremap_32.c
Christophe Leroy 8d05554dca powerpc: mm: convert to GENERIC_IOREMAP
By taking GENERIC_IOREMAP method, the generic generic_ioremap_prot(),
generic_iounmap(), and their generic wrapper ioremap_prot(), ioremap()
and iounmap() are all visible and available to arch. Arch needs to
provide wrapper functions to override the generic versions if there's
arch specific handling in its ioremap_prot(), ioremap() or iounmap().
This change will simplify implementation by removing duplicated code
with generic_ioremap_prot() and generic_iounmap(), and has the equivalent
functioality as before.

Here, add wrapper functions ioremap_prot() and iounmap() for powerpc's
special operation when ioremap() and iounmap().

Link: https://lkml.kernel.org/r/20230706154520.11257-18-bhe@redhat.com
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Niklas Schnelle <schnelle@linux.ibm.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18 10:12:35 -07:00

93 lines
2.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <mm/mmu_decl.h>
void __iomem *ioremap_wt(phys_addr_t addr, unsigned long size)
{
pgprot_t prot = pgprot_cached_wthru(PAGE_KERNEL);
return __ioremap_caller(addr, size, prot, __builtin_return_address(0));
}
EXPORT_SYMBOL(ioremap_wt);
void __iomem *
__ioremap_caller(phys_addr_t addr, unsigned long size, pgprot_t prot, void *caller)
{
unsigned long v;
phys_addr_t p, offset;
int err;
/*
* If the address lies within the first 16 MB, assume it's in ISA
* memory space
*/
if (addr < SZ_16M)
addr += _ISA_MEM_BASE;
/*
* Choose an address to map it to.
* Once the vmalloc system is running, we use it.
* Before then, we use space going down from IOREMAP_TOP
* (ioremap_bot records where we're up to).
*/
p = addr & PAGE_MASK;
offset = addr & ~PAGE_MASK;
size = PAGE_ALIGN(addr + size) - p;
#ifndef CONFIG_CRASH_DUMP
/*
* Don't allow anybody to remap normal RAM that we're using.
* mem_init() sets high_memory so only do the check after that.
*/
if (slab_is_available() && p <= virt_to_phys(high_memory - 1) &&
page_is_ram(__phys_to_pfn(p))) {
pr_warn("%s(): phys addr 0x%llx is RAM lr %ps\n", __func__,
(unsigned long long)p, __builtin_return_address(0));
return NULL;
}
#endif
if (size == 0)
return NULL;
/*
* Is it already mapped? Perhaps overlapped by a previous
* mapping.
*/
v = p_block_mapped(p);
if (v)
return (void __iomem *)v + offset;
if (slab_is_available())
return generic_ioremap_prot(addr, size, prot);
/*
* Should check if it is a candidate for a BAT mapping
*/
pr_warn("ioremap() called early from %pS. Use early_ioremap() instead\n", caller);
err = early_ioremap_range(ioremap_bot - size - PAGE_SIZE, p, size, prot);
if (err)
return NULL;
ioremap_bot -= size + PAGE_SIZE;
return (void __iomem *)ioremap_bot + offset;
}
void iounmap(volatile void __iomem *addr)
{
/*
* If mapped by BATs then there is nothing to do.
* Calling vfree() generates a benign warning.
*/
if (v_block_mapped((unsigned long)addr))
return;
generic_iounmap(addr);
}
EXPORT_SYMBOL(iounmap);