On 2.6 kernel, about DISCONTIGMEM issue

Feb 21, 2009 0 Replies
2.6 kernel DISCONTIGMEM issue There is a trouble wanted to ask for help$B!$(Bin linux 2.6$B!$(B On ARM9 board, the physical memory DDR-SDRAM have four banks, it's total 256MB$B!$(Bdecode of hw as follow.... DDR2-SDRAM Memory 1 0x3C00_0000 0x3FFF_FFFF - 64MB DDR2-SDRAM Memory 2 0x3400_0000 0x37FF_FFFF - 64MB DDR2-SDRAM Memory 3 0xC000_0000 0xC3FF_FFFF - 64MB DDR2-SDRAM Memory 4 0xC400_0000 0xC7FF_FFFF - 64MB Set to flat memory$B!$(Bit can be choose each bank1~4$B!$(Bbut limited to
64MB$B!$(B now I want to set all memory for OS or AP$B!$(Bexcept HW usage to buffer$B!$(B will left... DDR2-SDRAM Memory 1 0x3E20_0000 0x3FFF_FFFF - 30MB DDR2-SDRAM Memory 2 0x35A0_0000 0x37FF_FFFF - 38MB DDR2-SDRAM Memory 3 0xC200_0000 0xC3FF_FFFF - 32MB DDR2-SDRAM Memory 4 0xC400_0000 0xC5FF_FFFF - 32MB On HW requirement, it should start OS from 4th bank (C400_0000), then bank 4->3->1->2$B!$(BI will get 132MBmemory for Linux kernel$B!$(BI have been search about KERNEL ~kernel_home/include/asm-arm/memory.h shown method of DISCONTIGMEM to process the issue$B!$(Bbut follow by others example on kernel$B!$(Bby different decode$B!$(Bbut still sight to continues$B!$(Blike kernel_home\include\asm-arm\arch-aaec2000 as follow$B!'(B #ifdef CONFIG_DISCONTIGMEM /* * The nodes are the followings: * * node 0: 0xf000.0000 - 0xf3ff.ffff * node 1: 0xf400.0000 - 0xf7ff.ffff * node 2: 0xf800.0000 - 0xfbff.ffff * node 3: 0xfc00.0000 - 0xffff.ffff */ It's large different to my problem$B!$(BI don't know how to solve this problem$B!$(B And ask for help$B!$(BIn linux kernel, How can I port the needed code for discounting memory usage on physical memory that can set to use for Linuxsystem & AP, thanks a lots!!

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