![]() | |||||||||||||
Messages in this thread |
On Wed, Jan 23, 2002 at 04:47:37PM +0100, benh@kernel.crashing.org wrote: > >I don't think your PPC case needs the kernel mappings messed with. > >I really doubt the PPC will speculatively fetch/store to a TLB > >missing address.... unless you guys have large TLB mappings on > >PPC too? > > Yes, we use BATs (sort of built-in fixed large TLBs) to map > the lowmem (or entire RAM without CONFIG_HIGHMEM). Looking at bat_mapin_ram, it looks like we only map the first 512MB of RAM with BATs, so we actually map the 512MB - 768MB range with PTEs (and highmem starts at 768MB). Two of the DBATs are used by I/O mappings, so that only leaves two DBATs of 256MB each to map lowmem anyway. Am I missing something? By the way, does the "nobats" option currently work on PowerMac? -VAL - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ | ||||||||||||
| Last update: 2005-03-22 12:15 [from the cache] ©2003-2008 | |||||||||||||