arch/*/io.h: remove ioremap_uc in some architectures

From: Arnd Bergmann <[email protected]>

ioremap_uc() is only meaningful on old x86-32 systems with the PAT extension, and on ia64 with its slightly unconventional ioremap() behavior, everywhere else this is the same as ioremap() anyway.

Change the only driver that still references ioremap_uc() to only do so on x86-32/ia64 in order to allow removing that interface at some point in the future for the other architectures.

On some architectures, ioremap_uc() just returns NULL, changing the driver to call ioremap() means that they now have a chance of working correctly.

Signed-off-by Arnd Bergmann <[email protected]>

Signed-off-by Baoquan He <[email protected]>

Reviewed-by Luis Chamberlain <[email protected]>

Cc Helge Deller <[email protected]>

Cc Thomas Zimmermann <[email protected]>

Cc Christophe Leroy <[email protected]>

Cc [email protected]

Cc [email protected]

---
  drivers/video/fbdev/aty/atyfb_base.c | 4 ++++
  1 file changed, 4 insertions(+)

drivers/video/fbdev/aty/atyfb_base.c +4 -0

index 5c87817a4f4c..3dcf83f5e7b4 100644
@@ -3440,11 +3440,15 @@ static int atyfb_setup_generic(struct pci_dev *pdev, struct fb_info *info,
  	}
 
  	info->fix.mmio_start = raddr;
+#if defined(__i386__) || defined(__ia64__)
  	/*
  	 * By using strong UC we force the MTRR to never have an
  	 * effect on the MMIO region on both non-PAT and PAT systems.
  	 */
  	par->ati_regbase = ioremap_uc(info->fix.mmio_start, 0x1000);
+#else
+	par->ati_regbase = ioremap(info->fix.mmio_start, 0x1000);
+#endif
  	if (par->ati_regbase == NULL)
  		return -ENOMEM;
 

From: Jiaxun Yang <[email protected]>

With the adding, some default ioremap_xx methods defined in asm-generic/io.h can be used. E.g the default ioremap_uc() returning NULL.

We also massaged various headers to avoid nested includes.

Signed-off-by Baoquan He <[email protected]>

Signed-off-by Jiaxun Yang <[email protected]>

[[email protected]: Massage more headers, fix ioport defines]

Reviewed-by Arnd Bergmann <[email protected]>

Cc Thomas Bogendoerfer <[email protected]>

Cc Huacai Chen <[email protected]>

Cc [email protected]

Cc [email protected]

---
 arch/mips/include/asm/io.h      | 96 +++++++++++++++++++++++----------
 arch/mips/include/asm/mmiowb.h  |  4 +-
 arch/mips/include/asm/smp-ops.h |  2 -
 arch/mips/include/asm/smp.h     |  4 +-
 arch/mips/kernel/setup.c        |  1 +
 arch/mips/pci/pci-ip27.c        |  3 ++
 6 files changed, 75 insertions(+), 35 deletions(-)

ioremap_uc() is only meaningful on old x86-32 systems with the PAT extension, and on ia64 with its slightly unconventional ioremap() behavior. So remove the ioremap_uc() definition in architecutures other than x86 and ia64. These architectures all have asm-generic/io.h included and will have the default ioremap_uc() definition which returns NULL.

This changes the existing behaviour, while no need to worry about any breakage because in the only callsite of ioremap_uc(), code has been adjusted to eliminate the impact. Please see atyfb_setup_generic() of drivers/video/fbdev/aty/atyfb_base.c.

If any new invocation of ioremap_uc() need be added, please consider using ioremap() intead or adding a ARCH specific version if necessary.

Signed-off-by Baoquan He <[email protected]>

Acked-by Geert Uytterhoeven <[email protected]>

Acked-by Michael Ellerman <[email protected]> (powerpc)

Acked-by Helge Deller <[email protected]> # parisc

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

ioremap_uc() is only meaningful on old x86-32 systems with the PAT extension, and on ia64 with its slightly unconventional ioremap() behavior. So remove the ioremap_uc() definition in architecutures other than x86 and ia64. These architectures all have asm-generic/io.h included and will have the default ioremap_uc() definition which returns NULL.

This changes the existing behaviour, while no need to worry about any breakage because in the only callsite of ioremap_uc(), code has been adjusted to eliminate the impact. Please see atyfb_setup_generic() of drivers/video/fbdev/aty/atyfb_base.c.

If any new invocation of ioremap_uc() need be added, please consider using ioremap() intead or adding a ARCH specific version if necessary.

Signed-off-by Baoquan He <[email protected]>

Acked-by Geert Uytterhoeven <[email protected]>

Acked-by Michael Ellerman <[email protected]> (powerpc)

Acked-by Helge Deller <[email protected]> # parisc

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

---
 Documentation/driver-api/device-io.rst | 9 +++++----
 arch/alpha/include/asm/io.h            | 1 -
 arch/hexagon/include/asm/io.h          | 3 ---
 arch/m68k/include/asm/kmap.h           | 1 -
 arch/mips/include/asm/io.h             | 1 -

ioremap_uc() is only meaningful on old x86-32 systems with the PAT extension, and on ia64 with its slightly unconventional ioremap() behavior. So remove the ioremap_uc() definition in architecutures other than x86 and ia64. These architectures all have asm-generic/io.h included and will have the default ioremap_uc() definition which returns NULL.

This changes the existing behaviour, while no need to worry about any breakage because in the only callsite of ioremap_uc(), code has been adjusted to eliminate the impact. Please see atyfb_setup_generic() of drivers/video/fbdev/aty/atyfb_base.c.

If any new invocation of ioremap_uc() need be added, please consider using ioremap() intead or adding a ARCH specific version if necessary.

Signed-off-by Baoquan He <[email protected]>

Acked-by Geert Uytterhoeven <[email protected]>

Acked-by Michael Ellerman <[email protected]> (powerpc)

Acked-by Helge Deller <[email protected]> # parisc

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

Cc [email protected]

---
 Documentation/driver-api/device-io.rst | 9 +++++----
 arch/alpha/include/asm/io.h            | 1 -
 arch/hexagon/include/asm/io.h          | 3 ---
 arch/m68k/include/asm/kmap.h           | 1 -
 arch/mips/include/asm/io.h             | 1 -
 arch/parisc/include/asm/io.h           | 2 --
 arch/powerpc/include/asm/io.h          | 1 -
 arch/sh/include/asm/io.h               | 2 --
 arch/sparc/include/asm/io_64.h         | 1 -
 9 files changed, 5 insertions(+), 16 deletions(-)

Documentation/driver-api/device-io.rst +5 -4

index 2c7abd234f4e..d55384b106bd 100644
@@ -408,11 +408,12 @@ functions for details on the CPU side of things.
 ioremap_uc()
 ------------
 
-ioremap_uc() behaves like ioremap() except that on the x86 architecture without
-'PAT' mode, it marks memory as uncached even when the MTRR has designated
-it as cacheable, see Documentation/arch/x86/pat.rst.
+ioremap_uc() is only meaningful on old x86-32 systems with the PAT extension,
+and on ia64 with its slightly unconventional ioremap() behavior, everywhere
+elss ioremap_uc() defaults to return NULL.
 
-Portable drivers should avoid the use of ioremap_uc().
+
+Portable drivers should avoid the use of ioremap_uc(), use ioremap() instead.
 
 ioremap_cache()
 ---------------

arch/alpha/include/asm/io.h +0 -1

index 7aeaf7c30a6f..076f0e4e7f1e 100644
@@ -308,7 +308,6 @@ static inline void __iomem *ioremap(unsigned long port, unsigned long size)
 }
 
 #define ioremap_wc ioremap
-#define ioremap_uc ioremap
 
 static inline void iounmap(volatile void __iomem *addr)
 {

arch/hexagon/include/asm/io.h +0 -3

index e2b308e32a37..b7bc246dbcb1 100644
@@ -174,9 +174,6 @@ static inline void writel(u32 data, volatile void __iomem *addr)
 #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
 
 static inline void memcpy_fromio(void *dst, const volatile void __iomem *src,

arch/m68k/include/asm/kmap.h +0 -1

index 4efb3efa593a..b778f015c917 100644
@@ -25,7 +25,6 @@ static inline void __iomem *ioremap(unsigned long physaddr, unsigned long size)
 	return __ioremap(physaddr, size, IOMAP_NOCACHE_SER);
 }
 
-#define ioremap_uc ioremap
 #define ioremap_wt ioremap_wt
 static inline void __iomem *ioremap_wt(unsigned long physaddr,
 				       unsigned long size)

arch/mips/include/asm/io.h +0 -1

index 41d8bd5adef8..1ecf255efb40 100644
@@ -170,7 +170,6 @@ void iounmap(const volatile void __iomem *addr);
  */
 #define ioremap(offset, size)						\
 	ioremap_prot((offset), (size), _CACHE_UNCACHED)
-#define ioremap_uc		ioremap
 
 /*
  * ioremap_cache -	map bus memory into CPU space

arch/parisc/include/asm/io.h +0 -2

index 366537042465..48630c78714a 100644
@@ -132,8 +132,6 @@ static inline void gsc_writeq(unsigned long long val, unsigned long addr)
 
 #define ioremap_wc(addr, size)  \
 	ioremap_prot((addr), (size), _PAGE_IOREMAP)
-#define ioremap_uc(addr, size)  \
-	ioremap_prot((addr), (size), _PAGE_IOREMAP)
 
 #define pci_iounmap			pci_iounmap
 

arch/powerpc/include/asm/io.h +0 -1

index 0732b743e099..21bd3e8bffce 100644
@@ -900,7 +900,6 @@ void __iomem *ioremap_wt(phys_addr_t address, unsigned long size);
 #endif
 
 void __iomem *ioremap_coherent(phys_addr_t address, unsigned long size);
-#define ioremap_uc(addr, size)		ioremap((addr), (size))
 #define ioremap_cache(addr, size) \
 	ioremap_prot((addr), (size), pgprot_val(PAGE_KERNEL))
 

arch/sh/include/asm/io.h +0 -2

index f2f38e9d489a..790bea22c9b5 100644
@@ -302,8 +302,6 @@ unsigned long long poke_real_address_q(unsigned long long addr,
 	ioremap_prot((addr), (size), pgprot_val(PAGE_KERNEL))
 #endif /* CONFIG_MMU */
 
-#define ioremap_uc	ioremap
-
 /*
  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
  * access

arch/sparc/include/asm/io_64.h +0 -0

index 9303270b22f3..d8ee1442f303 100644

By adding <asm-generic/io.h> support, the duplicated phys_to_virt can be removed to use the default version in <asm-gneneric/io.h>.

Meanwhile move isa_bus_to_virt() down below <asm-generic/io.h> including to fix the compiling error of missing phys_to_virt definition.

By adding <asm-generic/io.h> support, the duplicated phys_to_virt can be removed to use the default version in <asm-gneneric/io.h>.

Meanwhile move isa_bus_to_virt() down below <asm-generic/io.h> including to fix the compiling error of missing phys_to_virt definition.

Signed-off-by Baoquan He <[email protected]>

Cc Thomas Bogendoerfer <[email protected]>

Cc Geert Uytterhoeven <[email protected]>

Cc Helge Deller <[email protected]>

Cc Serge Semin <[email protected]>

Cc Florian Fainelli <[email protected]>

Cc Huacai Chen <[email protected]>

Cc Jiaxun Yang <[email protected]>

Cc [email protected]

---
 arch/mips/include/asm/io.h | 28 +++++-----------------------
 1 file changed, 5 insertions(+), 23 deletions(-)

This patchset tries to remove ioremap_uc() in the current architectures except of x86 and ia64. They will use the default ioremap_uc version in <asm-generic/io.h> which returns NULL. Anyone who wants to add new invocation of ioremap_uc(), please consider using ioremap() instead or adding a new ARCH specific ioremap_uc(), or refer to the callsite in drivers/video/fbdev/aty/atyfb_base.c.

This change won't cuase breakage to the current kernel because in the only ioremap_uc callsite, an adjustment is made to eliminate impact in patch 1 of this series.

To get rid of all of them other than x86 and ia64, add asm-generic/io.h to asm/io.h of mips ARCH. With this adding, we can get rid of the ioremap_uc() in mips too. This is done in patch 2. And a followup patch 4 is added to remove duplicated code according to Arnd's suggestion.

Test:
=====
Except of Jiaxun's efficient testing on patch 2/4, I also did cross compiling of this series on mips64, building passed.

Quoted 16 lines · 在2023年9月21日九月 下午12:04，Baoquan He写道：

This patchset tries to remove ioremap_uc() in the current architectures except of x86 and ia64. They will use the default ioremap_uc version in <asm-generic/io.h> which returns NULL. Anyone who wants to add new invocation of ioremap_uc(), please consider using ioremap() instead or adding a new ARCH specific ioremap_uc(), or refer to the callsite in drivers/video/fbdev/aty/atyfb_base.c.

This change won't cuase breakage to the current kernel because in the only ioremap_uc callsite, an adjustment is made to eliminate impact in patch 1 of this series.

To get rid of all of them other than x86 and ia64, add asm-generic/io.h to asm/io.h of mips ARCH. With this adding, we can get rid of the ioremap_uc() in mips too. This is done in patch 2. And a followup patch 4 is added to remove duplicated code according to Arnd's suggestion.

Quoted 5 lines

Test:
=====
Except of Jiaxun's efficient testing on patch 2/4, I also did cross compiling of this series on mips64, building passed.

For whole series:

Tested-by Jiaxun Yang <[email protected]>

Hi Arnd and Thomas,

I've got some work pending based on this series, however I'm unclear about which tree this series will go since both of you give acked-by.

Given that there are some tree-wide modifications, I guess it should go into Arnd's asm-generic tree?