| Message ID | 20170914220513.9359-2-paul.burton@imgtec.com |
|---|---|
| State | Accepted |
| Commit | d4150ca6dea5f81f527fb2a01fcffc3d8dd09fc4 |
| Delegated to: | Tom Rini |
| Headers | show |
| Series | Add asm-generic/io.h; virt_to_phys(), phys_to_virt() for all arches | expand |
Am 15.09.2017 um 00:05 schrieb Paul Burton: > Most architectures currently supported by U-Boot use trivial > implementations of map_to_physmem & virt_to_phys which simply cast a > physical address to a pointer for use a virtual address & vice-versa. > This results in a lot of duplicate implementations of these mapping > functions. > > The set of functions provided by different architectures also differs, > with some having implementations of phys_to_virt & others not. A later > patch will make use of phys_to_virt in architecture-neutral code, and so > requires that it be provided for all architectures. > > This patch introduces an asm-generic/io.h which provides generic > implementations of address mapping functions, allowing the duplication > of them between architectures to be removed. Once architectures are > converted to make use of this generic header it will also ensure that > all of phys_to_virt, virt_to_phys, map_physmem & unmap_physmem are > provided. The 2 families of functions differ in that map_physmem may > create dynamic mappings whilst phys_to_virt may not & therefore is more > limited in scope but doesn't require information such as a length & > flags. > > This patch doesn't convert any architectures to make use of this generic > header - later patches in the series will do so. > > Signed-off-by: Paul Burton <paul.burton@imgtec.com> > Cc: Albert Aribaud <albert.u.boot@aribaud.net> > Cc: Alexey Brodkin <alexey.brodkin@synopsys.com> > Cc: Angelo Dureghello <angelo@sysam.it> > Cc: Bin Meng <bmeng.cn@gmail.com> > Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com> > Cc: Macpaul Lin <macpaul@andestech.com> > Cc: Michal Simek <monstr@monstr.eu> > Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org> > Cc: Thomas Chou <thomas@wytron.com.tw> > Cc: Wolfgang Denk <wd@denx.de> > Acked-by: Angelo Dureghello <angelo@sysam.it> > Tested-by: Angelo Dureghello <angelo@sysam.it> > Reviewed-by: Simon Glass <sjg@chromium.org> > Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
On Thu, Sep 14, 2017 at 03:05:01PM -0700, Paul Burton wrote: > Most architectures currently supported by U-Boot use trivial > implementations of map_to_physmem & virt_to_phys which simply cast a > physical address to a pointer for use a virtual address & vice-versa. > This results in a lot of duplicate implementations of these mapping > functions. > > The set of functions provided by different architectures also differs, > with some having implementations of phys_to_virt & others not. A later > patch will make use of phys_to_virt in architecture-neutral code, and so > requires that it be provided for all architectures. > > This patch introduces an asm-generic/io.h which provides generic > implementations of address mapping functions, allowing the duplication > of them between architectures to be removed. Once architectures are > converted to make use of this generic header it will also ensure that > all of phys_to_virt, virt_to_phys, map_physmem & unmap_physmem are > provided. The 2 families of functions differ in that map_physmem may > create dynamic mappings whilst phys_to_virt may not & therefore is more > limited in scope but doesn't require information such as a length & > flags. > > This patch doesn't convert any architectures to make use of this generic > header - later patches in the series will do so. > > Signed-off-by: Paul Burton <paul.burton@imgtec.com> > Cc: Albert Aribaud <albert.u.boot@aribaud.net> > Cc: Alexey Brodkin <alexey.brodkin@synopsys.com> > Cc: Angelo Dureghello <angelo@sysam.it> > Cc: Bin Meng <bmeng.cn@gmail.com> > Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com> > Cc: Macpaul Lin <macpaul@andestech.com> > Cc: Michal Simek <monstr@monstr.eu> > Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org> > Cc: Thomas Chou <thomas@wytron.com.tw> > Cc: Wolfgang Denk <wd@denx.de> > Acked-by: Angelo Dureghello <angelo@sysam.it> > Tested-by: Angelo Dureghello <angelo@sysam.it> > Reviewed-by: Simon Glass <sjg@chromium.org> > Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com> Applied to u-boot/master, thanks!
diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h new file mode 100644 index 0000000000..0f5160c6f1 --- /dev/null +++ b/include/asm-generic/io.h @@ -0,0 +1,110 @@ +/* + * Generic I/O functions. + * + * Copyright (c) 2016 Imagination Technologies Ltd. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __ASM_GENERIC_IO_H__ +#define __ASM_GENERIC_IO_H__ + +/* + * This file should be included at the end of each architecture-specific + * asm/io.h such that we may provide generic implementations without + * conflicting with architecture-specific code. + */ + +#ifndef __ASSEMBLY__ + +/** + * phys_to_virt() - Return a virtual address mapped to a given physical address + * @paddr: the physical address + * + * Returns a virtual address which the CPU can access that maps to the physical + * address @paddr. This should only be used where it is known that no dynamic + * mapping is required. In general, map_physmem should be used instead. + * + * Returns: a virtual address which maps to @paddr + */ +#ifndef phys_to_virt +static inline void *phys_to_virt(phys_addr_t paddr) +{ + return (void *)(unsigned long)paddr; +} +#endif + +/** + * virt_to_phys() - Return the physical address that a virtual address maps to + * @vaddr: the virtual address + * + * Returns the physical address which the CPU-accessible virtual address @vaddr + * maps to. + * + * Returns: the physical address which @vaddr maps to + */ +#ifndef virt_to_phys +static inline phys_addr_t virt_to_phys(void *vaddr) +{ + return (phys_addr_t)((unsigned long)vaddr); +} +#endif + +/* + * Flags for use with map_physmem() & unmap_physmem(). Architectures need not + * support all of these, in which case they will be defined as zero here & + * ignored. Callers that may run on multiple architectures should therefore + * treat them as hints rather than requirements. + */ +#ifndef MAP_NOCACHE +# define MAP_NOCACHE 0 /* Produce an uncached mapping */ +#endif +#ifndef MAP_WRCOMBINE +# define MAP_WRCOMBINE 0 /* Allow write-combining on the mapping */ +#endif +#ifndef MAP_WRBACK +# define MAP_WRBACK 0 /* Map using write-back caching */ +#endif +#ifndef MAP_WRTHROUGH +# define MAP_WRTHROUGH 0 /* Map using write-through caching */ +#endif + +/** + * map_physmem() - Return a virtual address mapped to a given physical address + * @paddr: the physical address + * @len: the length of the required mapping + * @flags: flags affecting the type of mapping + * + * Return a virtual address through which the CPU may access the memory at + * physical address @paddr. The mapping will be valid for at least @len bytes, + * and may be affected by flags passed to the @flags argument. This function + * may create new mappings, so should generally be paired with a matching call + * to unmap_physmem once the caller is finished with the memory in question. + * + * Returns: a virtual address suitably mapped to @paddr + */ +#ifndef map_physmem +static inline void *map_physmem(phys_addr_t paddr, unsigned long len, + unsigned long flags) +{ + return phys_to_virt(paddr); +} +#endif + +/** + * unmap_physmem() - Remove mappings created by a prior call to map_physmem() + * @vaddr: the virtual address which map_physmem() previously returned + * @flags: flags matching those originally passed to map_physmem() + * + * Unmap memory which was previously mapped by a call to map_physmem(). If + * map_physmem() dynamically created a mapping for the memory in question then + * unmap_physmem() will remove that mapping. + */ +#ifndef unmap_physmem +static inline void unmap_physmem(void *vaddr, unsigned long flags) +{ +} +#endif + +#endif /* !__ASSEMBLY__ */ +#endif /* __ASM_GENERIC_IO_H__ */