From 851d2e2fe8dbcbe3afcad6fc4569c881d8ad4ce9 Mon Sep 17 00:00:00 2001 From: "Tseng-Hui (Frank) Lin" Date: Mon, 2 May 2011 20:43:04 +0000 Subject: 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 --- arch/powerpc/platforms/Kconfig.cputype | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'arch/powerpc/platforms/Kconfig.cputype') diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index 7c1e1c64437..a1e623822a3 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -230,6 +230,24 @@ config VSX If in doubt, say Y here. +config PPC_ICSWX + bool "Support for PowerPC icswx coprocessor instruction" + depends on POWER4 + default n + ---help--- + + This option enables kernel support for the PowerPC Initiate + Coprocessor Store Word (icswx) coprocessor instruction on POWER7 + or newer processors. + + This option is only useful if you have a processor that supports + the icswx coprocessor instruction. It does not have any effect + on processors without the icswx coprocessor instruction. + + This option slightly increases kernel memory usage. + + If in doubt, say N here. + config SPE bool "SPE Support" depends on E200 || (E500 && !PPC_E500MC) -- cgit v1.2.3