[PATCH 24/26] riscv: use the generic ioremap code

Christoph Hellwig
2019-08-17T07:32:51Z

Use the generic ioremap code instead of providing a local version.
Note that this relies on the asm-generic no-op definition of
pgprot_noncached.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/riscv/Kconfig | 1 +
arch/riscv/include/asm/io.h | 3 --
arch/riscv/include/asm/pgtable.h | 6 +++
arch/riscv/mm/Makefile | 1 -
arch/riscv/mm/ioremap.c | 84 --------------------------------
5 files changed, 7 insertions(+), 88 deletions(-)
delete mode 100644 arch/riscv/mm/ioremap.c

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 59a4727ecd6c..468e7eba8916 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -30,6 +30,7 @@ config RISCV
select GENERIC_STRNLEN_USER
select GENERIC_SMP_IDLE_THREAD
select GENERIC_ATOMIC64 if !64BIT
+ select GENERIC_IOREMAP
select HAVE_ARCH_AUDITSYSCALL
select HAVE_MEMBLOCK_NODE_MAP
select HAVE_DMA_CONTIGUOUS
diff --git a/arch/riscv/include/asm/io.h b/arch/riscv/include/asm/io.h
index c1de6875cc77..df4c8812ff64 100644
--- a/arch/riscv/include/asm/io.h
+++ b/arch/riscv/include/asm/io.h
@@ -14,9 +14,6 @@
#include <linux/types.h>
#include <asm/mmiowb.h>

-extern void __iomem *ioremap(phys_addr_t offset, unsigned long size);
-extern void iounmap(volatile void __iomem *addr);
-
/* Generic IO read/write. These perform native-endian accesses. */
#define __raw_writeb __raw_writeb
static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index a364aba23d55..57be4723626c 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -61,6 +61,12 @@

#define PAGE_TABLE __pgprot(_PAGE_TABLE)

+/*
+ * The RISC-V ISA doesn't yet specify how to query or modify PMAs, so we can't
+ * change the properties of memory regions.
+ */
+#define _PAGE_IOREMAP _PAGE_KERNEL
+
extern pgd_t swapper_pg_dir[];

/* MAP_PRIVATE permissions: xwr (copy-on-write) */
diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile
index 74055e1d6f21..3b3a161feaa0 100644
--- a/arch/riscv/mm/Makefile
+++ b/arch/riscv/mm/Makefile
@@ -8,7 +8,6 @@ endif
obj-y += init.o
obj-y += fault.o
obj-y += extable.o
-obj-y += ioremap.o
obj-y += cacheflush.o
obj-y += context.o
obj-y += sifive_l2_cache.o
diff --git a/arch/riscv/mm/ioremap.c b/arch/riscv/mm/ioremap.c
deleted file mode 100644
index ac621ddb45c0..000000000000
--- a/arch/riscv/mm/ioremap.c
+++ /dev/null
@@ -1,84 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * (C) Copyright 1995 1996 Linus Torvalds
- * (C) Copyright 2012 Regents of the University of California
- */
-
-#include <linux/export.h>
-#include <linux/mm.h>
-#include <linux/vmalloc.h>
-#include <linux/io.h>
-
-#include <asm/pgtable.h>
-
-/*
- * Remap an arbitrary physical address space into the kernel virtual
- * address space. Needed when the kernel wants to access high addresses
- * directly.
- *
- * NOTE! We need to allow non-page-aligned mappings too: we will obviously
- * have to convert them into an offset in a page-aligned mapping, but the
- * caller shouldn't need to know that small detail.
- */
-static void __iomem *__ioremap_caller(phys_addr_t addr, size_t size,
- pgprot_t prot, void *caller)
-{
- phys_addr_t last_addr;
- unsigned long offset, vaddr;
- struct vm_struct *area;
-
- /* Disallow wrap-around or zero size */
- last_addr = addr + size - 1;
- if (!size || last_addr < addr)
- return NULL;
-
- /* Page-align mappings */
- offset = addr & (~PAGE_MASK);
- addr -= offset;
- size = PAGE_ALIGN(size + offset);
-
- area = get_vm_area_caller(size, VM_IOREMAP, caller);
- if (!area)
- return NULL;
- vaddr = (unsigned long)area->addr;
-
- if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) {
- free_vm_area(area);
- return NULL;
- }
-
- return (void __iomem *)(vaddr + offset);
-}
-
-/*
- * ioremap - map bus memory into CPU space
- * @offset: bus address of the memory
- * @size: size of the resource to map
- *
- * ioremap performs a platform specific sequence of operations to
- * make bus memory CPU accessible via the readb/readw/readl/writeb/
- * writew/writel functions and the other mmio helpers. The returned
- * address is not guaranteed to be usable directly as a virtual
- * address.
- *
- * Must be freed with iounmap.
- */
-void __iomem *ioremap(phys_addr_t offset, unsigned long size)
-{
- return __ioremap_caller(offset, size, PAGE_KERNEL,
- __builtin_return_address(0));
-}
-EXPORT_SYMBOL(ioremap);
-
-
-/**
- * iounmap - Free a IO remapping
- * @addr: virtual address from ioremap_*
- *
- * Caller must ensure there is only one unmapping for the same pointer.
- */
-void iounmap(volatile void __iomem *addr)
-{
- vunmap((void *)((unsigned long)addr & PAGE_MASK));
-}
-EXPORT_SYMBOL(iounmap);
--
2.20.1