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2015-06-07arch/*/io.h: Add ioremap_wt() to all architecturesToshi Kani
Add ioremap_wt() to all arch-specific asm/io.h headers which define ioremap_wc() locally. These headers do not include <asm-generic/iomap.h>. Some of them include <asm-generic/io.h>, but ioremap_wt() is defined for consistency since they define all ioremap_xxx locally. In all architectures without Write-Through support, ioremap_wt() is defined indentical to ioremap_nocache(). frv and m68k already have ioremap_writethrough(). On those we add ioremap_wt() indetical to ioremap_writethrough() and defines ARCH_HAS_IOREMAP_WT in both architectures. The ioremap_wt() interface is exported to drivers. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Elliott@hp.com Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: hch@lst.de Cc: hmh@hmh.eng.br Cc: jgross@suse.com Cc: konrad.wilk@oracle.com Cc: linux-mm <linux-mm@kvack.org> Cc: linux-nvdimm@lists.01.org Cc: stefan.bader@canonical.com Cc: yigal@plexistor.com Link: http://lkml.kernel.org/r/1433436928-31903-9-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-23metag: Fix ioremap_wc/ioremap_cached build errorsJames Hogan
When ioremap_wc() or ioremap_cached() are used without first including asm/pgtable.h, the _PAGE_CACHEABLE or _PAGE_WR_COMBINE definitions aren't found, resulting in build errors like the following (in next-20150323 due to "lib: devres: add a helper function for ioremap_wc"): lib/devres.c: In function ‘devm_ioremap_wc’: lib/devres.c:91: error: ‘_PAGE_WR_COMBINE’ undeclared We can't easily include asm/pgtable.h in asm/io.h due to dependency problems, so split out the _PAGE_* definitions from asm/pgtable.h into a separate asm/pgtable-bits.h header (as a couple of other architectures already do), and include that in io.h instead. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-metag@vger.kernel.org Cc: Abhilash Kesavan <a.kesavan@samsung.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-02metag: Memory handlingJames Hogan
Meta has instructions for accessing: - bytes - GETB (1 byte) - words - GETW (2 bytes) - doublewords - GETD (4 bytes) - longwords - GETL (8 bytes) All accesses must be aligned. Unaligned accesses can be detected and made to fault on Meta2, however it isn't possible to fix up unaligned writes so we don't bother fixing up reads either. This patch adds metag memory handling code including: - I/O memory (io.h, ioremap.c): Actually any virtual memory can be accessed with these helpers. A part of the non-MMUable address space is used for memory mapped I/O. The ioremap() function is implemented one to one for non-MMUable addresses. - User memory (uaccess.h, usercopy.c): User memory is directly accessible from privileged code. - Kernel memory (maccess.c): probe_kernel_write() needs to be overwridden to use the I/O functions when doing a simple aligned write to non-writecombined memory, otherwise the write may be split by the generic version. Note that due to the fact that a portion of the virtual address space is non-MMUable, and therefore always maps directly to the physical address space, metag specific I/O functions are made available (metag_in32, metag_out32 etc). These cast the address argument to a pointer so that they can be used with raw physical addresses. These accessors are only to be used for accessing fixed core Meta architecture registers in the non-MMU region, and not for any SoC/peripheral registers. Signed-off-by: James Hogan <james.hogan@imgtec.com>