[PATCH v7 02/19] hexagon: mm: Convert to GENERIC_IOREMAP

[Baoquan He]

By taking GENERIC_IOREMAP method, the generic ioremap_prot() and
iounmap() are visible and available to arch. This change will
simplify implementation by removing duplicated codes with generic
ioremap_prot() and iounmap(), and has the equivalent functioality.

For hexagon, the current ioremap() and iounmap() are the same as
generic version. After taking GENERIC_IOREMAP way, the old ioremap()
and iounmap() can be completely removed.

Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
Reviewed-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Cc: Brian Cain <bcain@xxxxxxxxxxx>
Cc: linux-hexagon@xxxxxxxxxxxxxxx
---
v6->v7:
- Fix building error reported by lkp test robot. Here I only fixed the
  redefinition of iounmap(), ignored the PCI_IOBASE warnings since
  Nathan kindly reminded me the warning is a generic issue, and Niklas
  is working on that within below patchset.
  https://lore.kernel.org/all/20230612160237.GA199007@dev-arch.thelio-3990X/T/#u

 arch/hexagon/Kconfig          |  1 +
 arch/hexagon/include/asm/io.h | 11 +++++----
 arch/hexagon/mm/ioremap.c     | 44 -----------------------------------
 3 files changed, 8 insertions(+), 48 deletions(-)
 delete mode 100644 arch/hexagon/mm/ioremap.c

diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
index 54eadf265178..17afffde1a7f 100644
--- a/arch/hexagon/Kconfig
+++ b/arch/hexagon/Kconfig
@@ -25,6 +25,7 @@ config HEXAGON
 	select NEED_SG_DMA_LENGTH
 	select NO_IOPORT_MAP
 	select GENERIC_IOMAP
+	select GENERIC_IOREMAP
 	select GENERIC_SMP_IDLE_THREAD
 	select STACKTRACE_SUPPORT
 	select GENERIC_CLOCKEVENTS_BROADCAST
diff --git a/arch/hexagon/include/asm/io.h b/arch/hexagon/include/asm/io.h
index 46a099de85b7..e2b308e32a37 100644
--- a/arch/hexagon/include/asm/io.h
+++ b/arch/hexagon/include/asm/io.h
@@ -27,8 +27,6 @@
 extern int remap_area_pages(unsigned long start, unsigned long phys_addr,
 				unsigned long end, unsigned long flags);
 
-extern void iounmap(const volatile void __iomem *addr);
-
 /* Defined in lib/io.c, needed for smc91x driver. */
 extern void __raw_readsw(const void __iomem *addr, void *data, int wordlen);
 extern void __raw_writesw(void __iomem *addr, const void *data, int wordlen);
@@ -170,8 +168,13 @@ static inline void writel(u32 data, volatile void __iomem *addr)
 #define writew_relaxed __raw_writew
 #define writel_relaxed __raw_writel
 
-void __iomem *ioremap(unsigned long phys_addr, unsigned long size);
-#define ioremap_uc(X, Y) ioremap((X), (Y))
+/*
+ * I/O memory mapping functions.
+ */
+#define _PAGE_IOREMAP (_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
+		       (__HEXAGON_C_DEV << 6))
+
+#define ioremap_uc(addr, size) ioremap((addr), (size))
 
 
 #define __raw_writel writel
diff --git a/arch/hexagon/mm/ioremap.c b/arch/hexagon/mm/ioremap.c
deleted file mode 100644
index 255c5b1ee1a7..000000000000
--- a/arch/hexagon/mm/ioremap.c
+++ /dev/null
@@ -1,44 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * I/O remap functions for Hexagon
- *
- * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
- */
-
-#include <linux/io.h>
-#include <linux/vmalloc.h>
-#include <linux/mm.h>
-
-void __iomem *ioremap(unsigned long phys_addr, unsigned long size)
-{
-	unsigned long last_addr, addr;
-	unsigned long offset = phys_addr & ~PAGE_MASK;
-	struct vm_struct *area;
-
-	pgprot_t prot = __pgprot(_PAGE_PRESENT|_PAGE_READ|_PAGE_WRITE
-					|(__HEXAGON_C_DEV << 6));
-
-	last_addr = phys_addr + size - 1;
-
-	/*  Wrapping not allowed  */
-	if (!size || (last_addr < phys_addr))
-		return NULL;
-
-	/*  Rounds up to next page size, including whole-page offset */
-	size = PAGE_ALIGN(offset + size);
-
-	area = get_vm_area(size, VM_IOREMAP);
-	addr = (unsigned long)area->addr;
-
-	if (ioremap_page_range(addr, addr+size, phys_addr, prot)) {
-		vunmap((void *)addr);
-		return NULL;
-	}
-
-	return (void __iomem *) (offset + addr);
-}
-
-void iounmap(const volatile void __iomem *addr)
-{
-	vunmap((void *) ((unsigned long) addr & PAGE_MASK));
-}
-- 
2.34.1