114 lines
2.6 KiB
C
114 lines
2.6 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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#include <linux/io.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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/**
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* Low level function to establish the page tables for an IO mapping
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*/
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void __iomem *__ioremap_at(phys_addr_t pa, void *ea, unsigned long size, pgprot_t prot)
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{
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int ret;
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unsigned long va = (unsigned long)ea;
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/* We don't support the 4K PFN hack with ioremap */
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if (pgprot_val(prot) & H_PAGE_4K_PFN)
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return NULL;
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if ((ea + size) >= (void *)IOREMAP_END) {
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pr_warn("Outside the supported range\n");
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return NULL;
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}
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WARN_ON(pa & ~PAGE_MASK);
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WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
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WARN_ON(size & ~PAGE_MASK);
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if (slab_is_available()) {
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ret = ioremap_page_range(va, va + size, pa, prot);
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if (ret)
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unmap_kernel_range(va, size);
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} else {
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ret = early_ioremap_range(va, pa, size, prot);
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}
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if (ret)
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return NULL;
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return (void __iomem *)ea;
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}
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EXPORT_SYMBOL(__ioremap_at);
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/**
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* Low level function to tear down the page tables for an IO mapping. This is
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* used for mappings that are manipulated manually, like partial unmapping of
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* PCI IOs or ISA space.
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*/
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void __iounmap_at(void *ea, unsigned long size)
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{
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WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
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WARN_ON(size & ~PAGE_MASK);
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unmap_kernel_range((unsigned long)ea, size);
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}
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EXPORT_SYMBOL(__iounmap_at);
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void __iomem *__ioremap_caller(phys_addr_t addr, unsigned long size,
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pgprot_t prot, void *caller)
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{
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phys_addr_t paligned, offset;
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void __iomem *ret;
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int err;
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/* We don't support the 4K PFN hack with ioremap */
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if (pgprot_val(prot) & H_PAGE_4K_PFN)
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return NULL;
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/*
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* Choose an address to map it to. Once the vmalloc system is running,
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* we use it. Before that, we map using addresses going up from
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* ioremap_bot. vmalloc will use the addresses from IOREMAP_BASE
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* through ioremap_bot.
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*/
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paligned = addr & PAGE_MASK;
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offset = addr & ~PAGE_MASK;
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size = PAGE_ALIGN(addr + size) - paligned;
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if (size == 0 || paligned == 0)
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return NULL;
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if (slab_is_available())
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return do_ioremap(paligned, offset, size, prot, caller);
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err = early_ioremap_range(ioremap_bot, paligned, size, prot);
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if (err)
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return NULL;
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ret = (void __iomem *)ioremap_bot + offset;
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ioremap_bot += size;
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return ret;
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}
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/*
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* Unmap an IO region and remove it from vmalloc'd list.
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* Access to IO memory should be serialized by driver.
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*/
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void iounmap(volatile void __iomem *token)
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{
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void *addr;
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if (!slab_is_available())
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return;
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addr = (void *)((unsigned long __force)PCI_FIX_ADDR(token) & PAGE_MASK);
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if ((unsigned long)addr < ioremap_bot) {
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pr_warn("Attempt to iounmap early bolted mapping at 0x%p\n", addr);
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return;
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}
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vunmap(addr);
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}
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EXPORT_SYMBOL(iounmap);
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