From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp06.au.ibm.com (e23smtp06.au.ibm.com [202.81.31.148]) (using TLSv1.2 with cipher CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 99ED71A0018 for ; Wed, 17 Feb 2016 18:27:43 +1100 (AEDT) Received: from localhost by e23smtp06.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 17 Feb 2016 17:27:42 +1000 Received: from d23relay09.au.ibm.com (d23relay09.au.ibm.com [9.185.63.181]) by d23dlp02.au.ibm.com (Postfix) with ESMTP id 4D9BE2BB005B for ; Wed, 17 Feb 2016 18:27:38 +1100 (EST) Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay09.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u1H7ROB641812000 for ; Wed, 17 Feb 2016 18:27:38 +1100 Received: from d23av02.au.ibm.com (localhost [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u1H7R0s0019937 for ; Wed, 17 Feb 2016 18:27:00 +1100 From: Alexey Kardashevskiy To: linuxppc-dev@lists.ozlabs.org Cc: Alexey Kardashevskiy , Michael Ellerman , Paul Mackerras , stable@vger.kernel.org.#.4.2+, Benjamin Herrenschmidt Subject: [PATCH kernel v2] powerpc/ioda: Set "read" permission when "write" is set Date: Wed, 17 Feb 2016 18:26:31 +1100 Message-Id: <1455693991-31405-1-git-send-email-aik@ozlabs.ru> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Quite often drivers set only "write" permission assuming that this includes "read" permission as well and this works on plenty platforms. However IODA2 is strict about this and produces an EEH when "read" permission is not and reading happens. This adds a workaround in IODA code to always add the "read" bit when the "write" bit is set. This fixes breakage introduced in 10b35b2b74 powerpc/powernv: Do not set "read" flag if direction==DMA_NONE Cc: stable@vger.kernel.org # 4.2+ Cc: Benjamin Herrenschmidt Signed-off-by: Alexey Kardashevskiy Tested-by: Douglas Miller --- arch/powerpc/platforms/powernv/pci.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c index 2f55c86..6a97ba4 100644 --- a/arch/powerpc/platforms/powernv/pci.c +++ b/arch/powerpc/platforms/powernv/pci.c @@ -599,6 +599,9 @@ int pnv_tce_build(struct iommu_table *tbl, long index, long npages, u64 rpn = __pa(uaddr) >> tbl->it_page_shift; long i; + if (proto_tce & TCE_PCI_WRITE) + proto_tce |= TCE_PCI_READ; + for (i = 0; i < npages; i++) { unsigned long newtce = proto_tce | ((rpn + i) << tbl->it_page_shift); @@ -620,6 +623,9 @@ int pnv_tce_xchg(struct iommu_table *tbl, long index, BUG_ON(*hpa & ~IOMMU_PAGE_MASK(tbl)); + if (newtce & TCE_PCI_WRITE) + newtce |= TCE_PCI_READ; + oldtce = xchg(pnv_tce(tbl, idx), cpu_to_be64(newtce)); *hpa = be64_to_cpu(oldtce) & ~(TCE_PCI_READ | TCE_PCI_WRITE); *direction = iommu_tce_direction(oldtce); -- 2.5.0.rc3