[PATCH v2 05/11] hexagon: mm: Convert to GENERIC_IOREMAP

[PATCH v2 05/11] hexagon: mm: Convert to GENERIC_IOREMAP

[Baoquan He]

With it, the old ioremap() and iounmap() can be perfectly removed
since they are duplicated with the standard functions.

Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Brian Cain <bcain@quicinc.com>
Cc: linux-hexagon@vger.kernel.org
---
 arch/hexagon/Kconfig          |  1 +
 arch/hexagon/include/asm/io.h |  9 +++++--
 arch/hexagon/mm/ioremap.c     | 44 -----------------------------------
 3 files changed, 8 insertions(+), 46 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 c33241425a5c..e2d3091ec9d6 100644
--- a/arch/hexagon/include/asm/io.h
+++ b/arch/hexagon/include/asm/io.h
@@ -170,8 +170,13 @@ 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

RE: [PATCH v2 05/11] hexagon: mm: Convert to GENERIC_IOREMAP

[Brian Cain]

> -----Original Message-----
> From: Baoquan He <bhe@redhat.com>
...
> With it, the old ioremap() and iounmap() can be perfectly removed
> since they are duplicated with the standard functions.
> 
> Signed-off-by: Baoquan He <bhe@redhat.com>
> Cc: Brian Cain <bcain@quicinc.com>
> Cc: linux-hexagon@vger.kernel.org
> ---

Acked-by: Brian Cain <bcain@quicinc.com>

Re: [PATCH v2 05/11] hexagon: mm: Convert to GENERIC_IOREMAP

[Christoph Hellwig]

On Sat, Aug 20, 2022 at 08:31:19AM +0800, Baoquan He wrote:
> With it, the old ioremap() and iounmap() can be perfectly removed
> since they are duplicated with the standard functions.

Can you write a somewhat better commit message explaining that it
switches to the generic code that has equivalent functionality?

> +#define ioremap_uc(addr, size) ioremap((addr), (size))

This is wrong and hexagon should use the asm-generic version of
ioremap_uc that returns NULL.

Re: [PATCH v2 05/11] hexagon: mm: Convert to GENERIC_IOREMAP

[Christophe Leroy]

Le 20/08/2022 à 02:31, Baoquan He a écrit :
> With it, the old ioremap() and iounmap() can be perfectly removed
> since they are duplicated with the standard functions.

I see nothing related to the preparation patches. Could this have been 
converted without all previous patches ? In that case I think this one 
should go in the begining of the series, it would help see which 
architectecture really needs the changes to the generic parts.

> 
> Signed-off-by: Baoquan He <bhe@redhat.com>
> Cc: Brian Cain <bcain@quicinc.com>
> Cc: linux-hexagon@vger.kernel.org
> ---
>   arch/hexagon/Kconfig          |  1 +
>   arch/hexagon/include/asm/io.h |  9 +++++--
>   arch/hexagon/mm/ioremap.c     | 44 -----------------------------------
>   3 files changed, 8 insertions(+), 46 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 c33241425a5c..e2d3091ec9d6 100644
> --- a/arch/hexagon/include/asm/io.h
> +++ b/arch/hexagon/include/asm/io.h
> @@ -170,8 +170,13 @@ 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));
> -}

Re: [PATCH v2 05/11] hexagon: mm: Convert to GENERIC_IOREMAP

[Baoquan He]

On 08/21/22 at 12:00am, Christoph Hellwig wrote:
> On Sat, Aug 20, 2022 at 08:31:19AM +0800, Baoquan He wrote:
> > With it, the old ioremap() and iounmap() can be perfectly removed
> > since they are duplicated with the standard functions.
> 
> Can you write a somewhat better commit message explaining that it
> switches to the generic code that has equivalent functionality?

OK, I will rephrase like below. Please check if it's OK.
==
By taking GENERIC_IOREMAP method, the generic ioremap_prot() and
iounmap() are visible and available to arch. Arch only needs to
provide implementation of arch_ioremap() or arch_iounmap() if there's
arch specific handling needed in its ioremap() or iounmap(). This
change will simplify implementation by removing duplicated codes with
generic ioremap() and iounma(), and has the equivalent functioality
as before.

> 
> > +#define ioremap_uc(addr, size) ioremap((addr), (size))
> 
> This is wrong and hexagon should use the asm-generic version of
> ioremap_uc that returns NULL.

I don't follow. Do you mean the function verion, but not a macro? Or
define it like below?

#define ioremap_uc(addr, size)  \
        ioremap_prot((addr), (size), _PAGE_IOREMAP)

Re: [PATCH v2 05/11] hexagon: mm: Convert to GENERIC_IOREMAP

[Baoquan He]

On 08/22/22 at 06:38am, Christophe Leroy wrote:
> 
> 
> Le 20/08/2022 à 02:31, Baoquan He a écrit :
> > With it, the old ioremap() and iounmap() can be perfectly removed
> > since they are duplicated with the standard functions.
> 
> I see nothing related to the preparation patches. Could this have been 
> converted without all previous patches ? In that case I think this one 
> should go in the begining of the series, it would help see which 
> architectecture really needs the changes to the generic parts.

You are right. Hexagon basically has the same implementation as standard
ioremap and iounmap code. I will move this at the beginning of patch
series in next round of post. Thanks for point this out.

> 
> > 
> > Signed-off-by: Baoquan He <bhe@redhat.com>
> > Cc: Brian Cain <bcain@quicinc.com>
> > Cc: linux-hexagon@vger.kernel.org
> > ---
> >   arch/hexagon/Kconfig          |  1 +
> >   arch/hexagon/include/asm/io.h |  9 +++++--
> >   arch/hexagon/mm/ioremap.c     | 44 -----------------------------------
> >   3 files changed, 8 insertions(+), 46 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 c33241425a5c..e2d3091ec9d6 100644
> > --- a/arch/hexagon/include/asm/io.h
> > +++ b/arch/hexagon/include/asm/io.h
> > @@ -170,8 +170,13 @@ 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));
> > -}