* Shilimkar, Santosh <santosh.shilimkar@xxxxxx> [090626 10:45]: > > -----Original Message----- > > From: linux-omap-owner@xxxxxxxxxxxxxxx > > [mailto:linux-omap-owner@xxxxxxxxxxxxxxx] On Behalf Of Tony Lindgren > > Sent: Friday, June 26, 2009 11:56 AM > > To: linux-omap@xxxxxxxxxxxxxxx > > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxxxxx > > Subject: RFC: Reclaim address space on omaps, Tony on vacation in July > > > > Hi all, > > > > Last week I posted some more omap io.h clean-up patches to > > the linux-omap > > list [1], and started looking at what it would take to > > reclaim lost address > > space on top of the io.h clean-up patches. > > > > Looks like we should be able to reclaim about 454MB of the 640MB > > of the lost IO address space by doing the following: > > > > 1. Start converting drivers using omap_read/write to use ioremap + > > __raw_read/write > > > > 2. Remove OMAP2_IO_ADDRESS macro, and replace it with with > > finer grained > > OMAP_L3_ADDRESS, OMAP_L4_ADDRESS, OMAP_SDRC_ADDRESS and so > > on macros > > > 3. Remap the the IO addresses in smaller sections in io.h so > > the virtual > > address for the blocks stays the same, and is counted down from the > > ARM reserved DMA address. > > > > After these steps, omap io.h would look like this: > > > > #define ARM_RESERVED_FUTURE_DMA 0xff000000 /* > > Documentation/arm/memory.txt */ > > #define OMAP23_L4_PHYS 0x48000000 > > #define OMAP24_L3_PHYS 0x68000000 > > #define OMAP4_L3_PHYS 0x44000000 > > #define OMAP4_L4_PHYS 0x4a000000 > > > > /* These virtual addresses are the same for all omaps */ > > #define OMAP_L3_SIZE SZ_1M > > #define OMAP_L3_VIRT (ARM_RESERVED_FUTURE_DMA - OMAP_L3_SIZE) > > #define OMAP_L4_SIZE (SZ_16M + SZ_1M) > > #define OMAP_L4_VIRT (OMAP_L3_VIRT - OMAP_L4_SIZE) > > #define OMAP_SDRC_SIZE SZ_1M > > #define OMAP_SDRC_BASE (OMAP_L4_VIRT - OMAP_SDRC_SIZE) > > ... > > > > > > #define OMAP_L3_ADDRESS(pa) (((pa) & ~0xff000000) + OMAP_L3_VIRT) > > #define OMAP_L4_ADDRESS(pa) (((pa) & ~0xff000000) + OMAP_L4_VIRT) > > #define OMAP_SDRC_ADDRESS(pa) (((pa) & ~0xff000000) + OMAP_SDRC_VIRT) > We surely need this going forward since there is also demand to fit higher > RAMS(256MB,512MB,1GB)in the system. > > Just to confirm, any further patches on this topic should be on top of this: > Tony Lindgren (3): > OMAP: Remove ifdefs for io.h > OMAP: Rename OMAP_MPUIO_BASE to OMAP1_MPUIO_BASE > OMAP: Remove OMAP_IO_ADDRESS, use OMAP1_IO_ADDRESS and OMAP2_IO_ADDRESS instead > > Is that correct Tony ? Yes it makes it easier as the patches above remove all the ifdefs for io.h. Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
