nds32: use generic ioremap

Use the generic ioremap_prot and iounmap helpers.

Note that the io.h include in pgtable.h had to be removed to not create
an include loop.  As far as I can tell there was no need for it to
start with.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Greentime Hu <green.hu@gmail.com>

arch/nds32/Kconfig

@@ -20,6 +20,7 @@ config NDS32
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_IRQ_CHIP
 	select GENERIC_IRQ_SHOW
+	select GENERIC_IOREMAP
 	select GENERIC_LIB_ASHLDI3
 	select GENERIC_LIB_ASHRDI3
 	select GENERIC_LIB_CMPDI2

arch/nds32/include/asm/io.h

@@ -6,8 +6,6 @@
 
 #include <linux/types.h>
 
-void __iomem *ioremap(phys_addr_t phys_addr, size_t size);
-extern void iounmap(volatile void __iomem *addr);
 #define __raw_writeb __raw_writeb
 static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
 {
@@ -80,6 +78,7 @@ static inline u32 __raw_readl(const volatile void __iomem *addr)
 #define writeb(v,c)	({ __iowmb(); writeb_relaxed((v),(c)); })
 #define writew(v,c)	({ __iowmb(); writew_relaxed((v),(c)); })
 #define writel(v,c)	({ __iowmb(); writel_relaxed((v),(c)); })
+
 #include <asm-generic/io.h>
 
 #endif /* __ASM_NDS32_IO_H */

arch/nds32/include/asm/pgtable.h

@@ -12,7 +12,6 @@
 #include <asm/nds32.h>
 #ifndef __ASSEMBLY__
 #include <asm/fixmap.h>
-#include <asm/io.h>
 #include <nds32_intrinsic.h>
 #endif
 
@@ -130,6 +129,9 @@ extern void __pgd_error(const char *file, int line, unsigned long val);
 #define _PAGE_CACHE		_PAGE_C_MEM_WB
 #endif
 
+#define _PAGE_IOREMAP \
+	(_PAGE_V | _PAGE_M_KRW | _PAGE_D | _PAGE_G | _PAGE_C_DEV)
+
 /*
  * + Level 1 descriptor (PMD)
  */

arch/nds32/mm/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-obj-y				:= extable.o tlb.o \
-				   fault.o init.o ioremap.o mmap.o \
+obj-y				:= extable.o tlb.o fault.o init.o mmap.o \
                                    mm-nds32.o cacheflush.o proc.o
 
 obj-$(CONFIG_ALIGNMENT_TRAP)	+= alignment.o

arch/nds32/mm/ioremap.c

-// SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2005-2017 Andes Technology Corporation
-
-#include <linux/vmalloc.h>
-#include <linux/io.h>
-#include <linux/mm.h>
-#include <asm/pgtable.h>
-
-void __iomem *ioremap(phys_addr_t phys_addr, size_t size);
-
-static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size,
-				      void *caller)
-{
-	struct vm_struct *area;
-	unsigned long addr, offset, last_addr;
-	pgprot_t prot;
-
-	/* Don't allow wraparound or zero size */
-	last_addr = phys_addr + size - 1;
-	if (!size || last_addr < phys_addr)
-		return NULL;
-
-	/*
-	 * Mappings have to be page-aligned
-	 */
-	offset = phys_addr & ~PAGE_MASK;
-	phys_addr &= PAGE_MASK;
-	size = PAGE_ALIGN(last_addr + 1) - phys_addr;
-
-	/*
-	 * Ok, go for it..
-	 */
-	area = get_vm_area_caller(size, VM_IOREMAP, caller);
-	if (!area)
-		return NULL;
-
-	area->phys_addr = phys_addr;
-	addr = (unsigned long)area->addr;
-	prot = __pgprot(_PAGE_V | _PAGE_M_KRW | _PAGE_D |
-			_PAGE_G | _PAGE_C_DEV);
-	if (ioremap_page_range(addr, addr + size, phys_addr, prot)) {
-		vunmap((void *)addr);
-		return NULL;
-	}
-	return (__force void __iomem *)(offset + (char *)addr);
-
-}
-
-void __iomem *ioremap(phys_addr_t phys_addr, size_t size)
-{
-	return __ioremap_caller(phys_addr, size,
-				__builtin_return_address(0));
-}
-
-EXPORT_SYMBOL(ioremap);
-
-void iounmap(volatile void __iomem * addr)
-{
-	vunmap((void *)(PAGE_MASK & (unsigned long)addr));
-}
-
-EXPORT_SYMBOL(iounmap);