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// 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;
/*
* 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;
/*
* If the address lies within the first 16 MB, assume it's in ISA
* memory space
*/
if (p < 16 * 1024 * 1024)
p += _ISA_MEM_BASE;
#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 do_ioremap(p, offset, size, prot, caller);
/*
* 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;
if (addr > high_memory && (unsigned long)addr < ioremap_bot)
vunmap((void *)(PAGE_MASK & (unsigned long)addr));
}
EXPORT_SYMBOL(iounmap);
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