linux/arch/powerpc/mm/ioremap.c

// SPDX-License-Identifier: GPL-2.0-or-later

#include <linux/io.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <asm/io-workarounds.h>

unsigned long ioremap_bot;
EXPORT_SYMBOL(ioremap_bot);

void __iomem *ioremap(phys_addr_t addr, unsigned long size)
{
	pgprot_t prot = pgprot_noncached(PAGE_KERNEL);
	void *caller = __builtin_return_address(0);

	if (iowa_is_active())
		return iowa_ioremap(addr, size, prot, caller);
	return __ioremap_caller(addr, size, prot, caller);
}
EXPORT_SYMBOL(ioremap);

void __iomem *ioremap_wc(phys_addr_t addr, unsigned long size)
{
	pgprot_t prot = pgprot_noncached_wc(PAGE_KERNEL);
	void *caller = __builtin_return_address(0);

	if (iowa_is_active())
		return iowa_ioremap(addr, size, prot, caller);
	return __ioremap_caller(addr, size, prot, caller);
}
EXPORT_SYMBOL(ioremap_wc);

void __iomem *ioremap_coherent(phys_addr_t addr, unsigned long size)
{
	pgprot_t prot = pgprot_cached(PAGE_KERNEL);
	void *caller = __builtin_return_address(0);

	if (iowa_is_active())
		return iowa_ioremap(addr, size, prot, caller);
	return __ioremap_caller(addr, size, prot, caller);
}

void __iomem *ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags)
{
	pte_t pte = __pte(flags);
	void *caller = __builtin_return_address(0);

	/* writeable implies dirty for kernel addresses */
	if (pte_write(pte))
		pte = pte_mkdirty(pte);

	/* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
	pte = pte_exprotect(pte);
	pte = pte_mkprivileged(pte);

	if (iowa_is_active())
		return iowa_ioremap(addr, size, pte_pgprot(pte), caller);
	return __ioremap_caller(addr, size, pte_pgprot(pte), caller);
}
EXPORT_SYMBOL(ioremap_prot);

int ioremap_range(unsigned long ea, phys_addr_t pa, unsigned long size, pgprot_t prot)
{
	unsigned long i;

	if (slab_is_available()) {
		int err = ioremap_page_range(ea, ea + size, pa, prot);

		if (err)
			unmap_kernel_range(ea, size);
		return err;
	}

	for (i = 0; i < size; i += PAGE_SIZE) {
		int err = map_kernel_page(ea + i, pa + i, prot);

		if (WARN_ON_ONCE(err))  /* Should clean up */
			return err;
	}

	return 0;
}

void __iomem *do_ioremap(phys_addr_t pa, phys_addr_t offset, unsigned long size,
			 pgprot_t prot, void *caller)
{
	struct vm_struct *area;
	int ret;

	area = __get_vm_area_caller(size, VM_IOREMAP, IOREMAP_START, IOREMAP_END, caller);
	if (area == NULL)
		return NULL;

	area->phys_addr = pa;
	ret = ioremap_range((unsigned long)area->addr, pa, size, prot);
	if (!ret)
		return (void __iomem *)area->addr + offset;

	free_vm_area(area);

	return NULL;
}