From: Tseng-Hui (Frank) Lin Date: Mon, 2 May 2011 20:43:04 +0000 (+0000) Subject: powerpc: Add Initiate Coprocessor Store Word (icswx) support X-Git-Tag: v3.0-rc1~385^2~83 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=851d2e2fe8dbcbe3afcad6fc4569c881d8ad4ce9;p=pandora-kernel.git powerpc: Add Initiate Coprocessor Store Word (icswx) support Icswx is a PowerPC instruction to send data to a co-processor. On Book-S processors the LPAR_ID and process ID (PID) of the owning process are registered in the window context of the co-processor at initialization time. When the icswx instruction is executed the L2 generates a cop-reg transaction on PowerBus. The transaction has no address and the processor does not perform an MMU access to authenticate the transaction. The co-processor compares the LPAR_ID and the PID included in the transaction and the LPAR_ID and PID held in the window context to determine if the process is authorized to generate the transaction. The OS needs to assign a 16-bit PID for the process. This cop-PID needs to be updated during context switch. The cop-PID needs to be destroyed when the context is destroyed. Signed-off-by: Sonny Rao Signed-off-by: Tseng-Hui (Frank) Lin Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt --- Reading git-diff-tree failed