From e2dc9d598b4945be932e176ff19b9f804c7ab1a4 Mon Sep 17 00:00:00 2001
From: Grazvydas Ignotas <notasas@gmail.com>
Date: Sat, 7 Feb 2015 21:20:35 +0200
Subject: [PATCH] ARM: implement ioremap_prot

---
 arch/arm/Kconfig                            |  1 +
 arch/arm/include/asm/io.h                   |  3 ++
 arch/arm/include/asm/pgtable-2level-types.h |  2 ++
 arch/arm/mm/ioremap.c                       | 37 +++++++++++++++++++++
 4 files changed, 43 insertions(+)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 3ea62da77aa5..870794acb02f 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -30,6 +30,7 @@ config ARM
 	select HAVE_C_RECORDMCOUNT
 	select HAVE_GENERIC_HARDIRQS
 	select HAVE_SPARSE_IRQ
+	select HAVE_IOREMAP_PROT
 	select GENERIC_IRQ_SHOW
 	select CPU_PM if (SUSPEND || CPU_IDLE)
 	help
diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
index 065d100fa63e..cb81b3b97c9c 100644
--- a/arch/arm/include/asm/io.h
+++ b/arch/arm/include/asm/io.h
@@ -83,6 +83,9 @@ extern void __iomem *__arm_ioremap(unsigned long, size_t, unsigned int);
 extern void __iomem *__arm_ioremap_exec(unsigned long, size_t, bool cached);
 extern void __iounmap(volatile void __iomem *addr);
 
+extern void __iomem *ioremap_prot(resource_size_t, unsigned long size,
+	unsigned long prot_val);
+
 /*
  * Bad read/write accesses...
  */
diff --git a/arch/arm/include/asm/pgtable-2level-types.h b/arch/arm/include/asm/pgtable-2level-types.h
index 66cb5b0e89c5..93ce673183a0 100644
--- a/arch/arm/include/asm/pgtable-2level-types.h
+++ b/arch/arm/include/asm/pgtable-2level-types.h
@@ -64,4 +64,6 @@ typedef pteval_t pgprot_t;
 
 #endif /* STRICT_MM_TYPECHECKS */
 
+#define pte_pgprot(pte)	__pgprot(pte_val(pte))
+
 #endif	/* _ASM_PGTABLE_2LEVEL_TYPES_H */
diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index 80632e8d7538..c6f20dc3218c 100644
--- a/arch/arm/mm/ioremap.c
+++ b/arch/arm/mm/ioremap.c
@@ -335,6 +335,43 @@ __arm_ioremap_exec(unsigned long phys_addr, size_t size, bool cached)
 			__builtin_return_address(0));
 }
 
+void __iomem *ioremap_prot(resource_size_t phys_addr, unsigned long size,
+				unsigned long prot_val)
+{
+	const struct mem_type *type;
+	unsigned long addr;
+	struct vm_struct * area;
+	pteval_t prot_pte;
+	int err;
+
+	size = PAGE_ALIGN(size);
+
+	type = get_mem_type(MT_DEVICE);
+	if (!type)
+		return NULL;
+
+	prot_pte = type->prot_pte & ~L_PTE_MT_MASK;
+	prot_pte |= prot_val & L_PTE_MT_MASK;
+
+	area = get_vm_area_caller(size, VM_IOREMAP,
+				  __builtin_return_address(0));
+	if (!area)
+		return NULL;
+	addr = (unsigned long)area->addr;
+
+	err = ioremap_page_range(addr, addr + size, phys_addr,
+				 __pgprot(prot_pte));
+	if (err) {
+		vunmap((void *)addr);
+		return NULL;
+	}
+
+	flush_cache_vmap(addr, addr + size);
+	return (void __iomem *)addr;
+}
+
+EXPORT_SYMBOL(ioremap_prot);
+
 void __iounmap(volatile void __iomem *io_addr)
 {
 	void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
-- 
2.39.2