1 files changed, 113 insertions, 0 deletions
diff --git a/arch/powerpc/mm/ioremap_64.c b/arch/powerpc/mm/ioremap_64.c
new file mode 100644
index 000000000000..fd29e51700cd
--- /dev/null
+++ b/arch/powerpc/mm/ioremap_64.c
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+/**
+ * Low level function to establish the page tables for an IO mapping
+ */
+void __iomem *__ioremap_at(phys_addr_t pa, void *ea, unsigned long size, pgprot_t prot)
+{
+	int ret;
+	unsigned long va = (unsigned long)ea;
+
+	/* We don't support the 4K PFN hack with ioremap */
+	if (pgprot_val(prot) & H_PAGE_4K_PFN)
+		return NULL;
+
+	if ((ea + size) >= (void *)IOREMAP_END) {
+		pr_warn("Outside the supported range\n");
+		return NULL;
+	}
+
+	WARN_ON(pa & ~PAGE_MASK);
+	WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
+	WARN_ON(size & ~PAGE_MASK);
+
+	if (slab_is_available()) {
+		ret = ioremap_page_range(va, va + size, pa, prot);
+		if (ret)
+			unmap_kernel_range(va, size);
+	} else {
+		ret = early_ioremap_range(va, pa, size, prot);
+	}
+
+	if (ret)
+		return NULL;
+
+	return (void __iomem *)ea;
+}
+EXPORT_SYMBOL(__ioremap_at);
+
+/**
+ * Low level function to tear down the page tables for an IO mapping. This is
+ * used for mappings that are manipulated manually, like partial unmapping of
+ * PCI IOs or ISA space.
+ */
+void __iounmap_at(void *ea, unsigned long size)
+{
+	WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
+	WARN_ON(size & ~PAGE_MASK);
+
+	unmap_kernel_range((unsigned long)ea, size);
+}
+EXPORT_SYMBOL(__iounmap_at);
+
+void __iomem *__ioremap_caller(phys_addr_t addr, unsigned long size,
+			       pgprot_t prot, void *caller)
+{
+	phys_addr_t paligned, offset;
+	void __iomem *ret;
+	int err;
+
+	/* We don't support the 4K PFN hack with ioremap */
+	if (pgprot_val(prot) & H_PAGE_4K_PFN)
+		return NULL;
+
+	/*
+	 * Choose an address to map it to. Once the vmalloc system is running,
+	 * we use it. Before that, we map using addresses going up from
+	 * ioremap_bot.  vmalloc will use the addresses from IOREMAP_BASE
+	 * through ioremap_bot.
+	 */
+	paligned = addr & PAGE_MASK;
+	offset = addr & ~PAGE_MASK;
+	size = PAGE_ALIGN(addr + size) - paligned;
+
+	if (size == 0 || paligned == 0)
+		return NULL;
+
+	if (slab_is_available())
+		return do_ioremap(paligned, offset, size, prot, caller);
+
+	err = early_ioremap_range(ioremap_bot, paligned, size, prot);
+	if (err)
+		return NULL;
+
+	ret = (void __iomem *)ioremap_bot + offset;
+	ioremap_bot += size;
+
+	return ret;
+}
+
+/*
+ * Unmap an IO region and remove it from vmalloc'd list.
+ * Access to IO memory should be serialized by driver.
+ */
+void iounmap(volatile void __iomem *token)
+{
+	void *addr;
+
+	if (!slab_is_available())
+		return;
+
+	addr = (void *)((unsigned long __force)PCI_FIX_ADDR(token) & PAGE_MASK);
+
+	if ((unsigned long)addr < ioremap_bot) {
+		pr_warn("Attempt to iounmap early bolted mapping at 0x%p\n", addr);
+		return;
+	}
+	vunmap(addr);
+}
+EXPORT_SYMBOL(iounmap);