1 // SPDX-License-Identifier: GPL-2.0-or-later
4 #include <linux/slab.h>
5 #include <linux/vmalloc.h>
8 * Low level function to establish the page tables for an IO mapping
10 void __iomem *__ioremap_at(phys_addr_t pa, void *ea, unsigned long size, pgprot_t prot)
13 unsigned long va = (unsigned long)ea;
15 /* We don't support the 4K PFN hack with ioremap */
16 if (pgprot_val(prot) & H_PAGE_4K_PFN)
19 if ((ea + size) >= (void *)IOREMAP_END) {
20 pr_warn("Outside the supported range\n");
24 WARN_ON(pa & ~PAGE_MASK);
25 WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
26 WARN_ON(size & ~PAGE_MASK);
28 if (slab_is_available()) {
29 ret = ioremap_page_range(va, va + size, pa, prot);
31 unmap_kernel_range(va, size);
33 ret = early_ioremap_range(va, pa, size, prot);
39 return (void __iomem *)ea;
41 EXPORT_SYMBOL(__ioremap_at);
44 * Low level function to tear down the page tables for an IO mapping. This is
45 * used for mappings that are manipulated manually, like partial unmapping of
46 * PCI IOs or ISA space.
48 void __iounmap_at(void *ea, unsigned long size)
50 WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
51 WARN_ON(size & ~PAGE_MASK);
53 unmap_kernel_range((unsigned long)ea, size);
55 EXPORT_SYMBOL(__iounmap_at);
57 void __iomem *__ioremap_caller(phys_addr_t addr, unsigned long size,
58 pgprot_t prot, void *caller)
60 phys_addr_t paligned, offset;
64 /* We don't support the 4K PFN hack with ioremap */
65 if (pgprot_val(prot) & H_PAGE_4K_PFN)
69 * Choose an address to map it to. Once the vmalloc system is running,
70 * we use it. Before that, we map using addresses going up from
71 * ioremap_bot. vmalloc will use the addresses from IOREMAP_BASE
72 * through ioremap_bot.
74 paligned = addr & PAGE_MASK;
75 offset = addr & ~PAGE_MASK;
76 size = PAGE_ALIGN(addr + size) - paligned;
78 if (size == 0 || paligned == 0)
81 if (slab_is_available())
82 return do_ioremap(paligned, offset, size, prot, caller);
84 pr_warn("ioremap() called early from %pS. Use early_ioremap() instead\n", caller);
86 err = early_ioremap_range(ioremap_bot, paligned, size, prot);
90 ret = (void __iomem *)ioremap_bot + offset;
97 * Unmap an IO region and remove it from vmalloc'd list.
98 * Access to IO memory should be serialized by driver.
100 void iounmap(volatile void __iomem *token)
104 if (!slab_is_available())
107 addr = (void *)((unsigned long __force)PCI_FIX_ADDR(token) & PAGE_MASK);
109 if ((unsigned long)addr < ioremap_bot) {
110 pr_warn("Attempt to iounmap early bolted mapping at 0x%p\n", addr);
115 EXPORT_SYMBOL(iounmap);