kernel.git/arch/arm/include/asm/fixmap.h, branch linux-3.17.y

ARM: 8031/2: change fixmap mapping region to support 32 CPUs

2014-04-23T10:09:42Z

In 32-bit ARM systems, the fixmap mapping region can support no more than 14 CPUs(total: 896k; one CPU: 64K). And we can configure NR_CPUS up to 32. So there is a mismatch. This patch moves fixmapping region downwards to region 0xffc00000- 0xffe00000. Then the fixmap mapping region can support up to 32 CPUs. Reviewed-by: Nicolas Pitre Signed-off-by: Liu Hua Signed-off-by: Russell King

ARM: 8031/1: fixmap: remove FIX_KMAP_BEGIN and FIX_KMAP_END

2014-04-23T10:09:27Z

It seems that these two macros are not used by non architecture specific code. And on ARM FIX_KMAP_BEGIN equals zero. This patch removes these two macros. Instead, using FIX_KMAP_NR_PTES to tell the pte number belonged to fixmap mapping region. The code will become clearer when I introduce a bugfix on fixmap mapping region. Reviewed-by: Nicolas Pitre Signed-off-by: Liu Hua Signed-off-by: Russell King

[ARM] fixmap support

2009-03-16T01:01:20Z

This is the minimum fixmap interface expected to be implemented by architectures supporting highmem. We have a second level page table already allocated and covering 0xfff00000-0xffffffff because the exception vector page is located at 0xffff0000, and various cache tricks already use some entries above 0xffff0000. Therefore the PTEs covering 0xfff00000-0xfffeffff are free to be used. However the XScale cache flushing code already uses virtual addresses between 0xfffe0000 and 0xfffeffff. So this reserves the 0xfff00000-0xfffdffff range for fixmap stuff. The Documentation/arm/memory.txt information is updated accordingly, including the information about the actual top of DMA memory mapping region which didn't match the code. Signed-off-by: Nicolas Pitre