char/agp: introduce asm-generic/agp.h

There are several architectures that duplicate definitions of
map_page_into_agp(), unmap_page_from_agp() and flush_agp_cache().

Define those in asm-generic/agp.h and use it instead of duplicated
per-architecture headers.
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/alpha/include/asm/Kbuild

 # SPDX-License-Identifier: GPL-2.0
 
 generated-y += syscall_table.h
+generic-y += agp.h
 generic-y += export.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h

arch/alpha/include/asm/agp.h

-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef AGP_H
-#define AGP_H 1
-
-#include <asm/io.h>
-
-/* dummy for now */
-
-#define map_page_into_agp(page)		do { } while (0)
-#define unmap_page_from_agp(page)	do { } while (0)
-#define flush_agp_cache() mb()
-
-#endif

arch/ia64/include/asm/Kbuild

 # SPDX-License-Identifier: GPL-2.0
 generated-y += syscall_table.h
+generic-y += agp.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h
 generic-y += vtime.h

arch/ia64/include/asm/agp.h

-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_IA64_AGP_H
-#define _ASM_IA64_AGP_H
-
-/*
- * IA-64 specific AGP definitions.
- *
- * Copyright (C) 2002-2003 Hewlett-Packard Co
- *	David Mosberger-Tang <davidm@hpl.hp.com>
- */
-
-/*
- * To avoid memory-attribute aliasing issues, we require that the AGPGART engine operate
- * in coherent mode, which lets us map the AGP memory as normal (write-back) memory
- * (unlike x86, where it gets mapped "write-coalescing").
- */
-#define map_page_into_agp(page)		do { } while (0)
-#define unmap_page_from_agp(page)	do { } while (0)
-#define flush_agp_cache()		mb()
-
-#endif /* _ASM_IA64_AGP_H */

arch/parisc/include/asm/Kbuild

 # SPDX-License-Identifier: GPL-2.0
 generated-y += syscall_table_32.h
 generated-y += syscall_table_64.h
+generic-y += agp.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h
 generic-y += user.h

arch/parisc/include/asm/agp.h

-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_PARISC_AGP_H
-#define _ASM_PARISC_AGP_H
-
-/*
- * PARISC specific AGP definitions.
- * Copyright (c) 2006 Kyle McMartin <kyle@parisc-linux.org>
- *
- */
-
-#define map_page_into_agp(page)		do { } while (0)
-#define unmap_page_from_agp(page)	do { } while (0)
-#define flush_agp_cache()		mb()
-
-#endif /* _ASM_PARISC_AGP_H */

arch/powerpc/include/asm/Kbuild

@@ -2,6 +2,7 @@
 generated-y += syscall_table_32.h
 generated-y += syscall_table_64.h
 generated-y += syscall_table_spu.h
+generic-y += agp.h
 generic-y += export.h
 generic-y += kvm_types.h
 generic-y += mcs_spinlock.h

arch/sparc/include/asm/Kbuild

 # SPDX-License-Identifier: GPL-2.0
 generated-y += syscall_table_32.h
 generated-y += syscall_table_64.h
+generic-y += agp.h
 generic-y += export.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h

arch/sparc/include/asm/agp.h

-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef AGP_H
-#define AGP_H 1
-
-/* dummy for now */
-
-#define map_page_into_agp(page)		do { } while (0)
-#define unmap_page_from_agp(page)	do { } while (0)
-#define flush_agp_cache()		mb()
-
-#endif

arch/powerpc/include/asm/agp.h → include/asm-generic/agp.h

 /* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_POWERPC_AGP_H
-#define _ASM_POWERPC_AGP_H
-#ifdef __KERNEL__
+#ifndef _ASM_GENERIC_AGP_H
+#define _ASM_GENERIC_AGP_H
 
 #include <asm/io.h>
 
@@ -9,5 +8,4 @@
 #define unmap_page_from_agp(page) do {} while (0)
 #define flush_agp_cache() mb()
 
-#endif /* __KERNEL__ */
-#endif	/* _ASM_POWERPC_AGP_H */
+#endif	/* _ASM_GENERIC_AGP_H */