[PATCH 2.6.12 1/1] altix: disable TIOCA GART TLB prefetching

From: Mark Maule <maule_at_sgi.com>
Date: 2005-03-17 09:48:59
Patch to disable SGI TIOCA GART TLB prefetching due to hw bug.

Signed-off-by: Mark Maule <maule@sgi.com>

===== arch/ia64/sn/pci/tioca_provider.c 1.1 vs 1.2 =====
--- 1.1/arch/ia64/sn/pci/tioca_provider.c	2005-03-10 16:33:04 -06:00
+++ 1.2/arch/ia64/sn/pci/tioca_provider.c	2005-03-16 16:28:48 -06:00
@@ -171,15 +171,15 @@
 	 *      use agp op-combining
 	 *      use GET semantics to fetch memory
 	 *      participate in coherency domain
-	 *      prefetch TLB entries
+	 * 	DISABLE GART PREFETCHING due to hw bug tracked in SGI PV930029
 	 */
 
 	ca_base->ca_control1 |= CA_AGPDMA_OP_ENB_COMBDELAY;	/* PV895469 ? */
 	ca_base->ca_control2 &= ~(CA_GART_MEM_PARAM);
 	ca_base->ca_control2 |= (0x2ull << CA_GART_MEM_PARAM_SHFT);
 	tioca_kern->ca_gart_iscoherent = 1;
-	ca_base->ca_control2 |=
-	    (CA_GART_WR_PREFETCH_ENB | CA_GART_RD_PREFETCH_ENB);
+	ca_base->ca_control2 &=
+	    ~(CA_GART_WR_PREFETCH_ENB | CA_GART_RD_PREFETCH_ENB);
 
 	/*
 	 * Unmask GART fetch error interrupts.  Clear residual errors first.
-
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Received on Wed Mar 16 17:49:15 2005

This archive was generated by hypermail 2.1.8 : 2005-08-02 09:20:37 EST