Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757185Ab2HRRec (ORCPT ); Sat, 18 Aug 2012 13:34:32 -0400 Received: from filtteri5.pp.htv.fi ([213.243.153.188]:39723 "EHLO filtteri5.pp.htv.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755885Ab2HRRe2 (ORCPT ); Sat, 18 Aug 2012 13:34:28 -0400 From: Aaro Koskinen To: benh@kernel.crashing.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: [PATCH] powerpc: dma-iommu: fix IOMMU window check Date: Sat, 18 Aug 2012 20:34:15 +0300 Message-Id: <1345311255-30657-1-git-send-email-aaro.koskinen@iki.fi> X-Mailer: git-send-email 1.7.2.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1757 Lines: 44 Checking for device mask to cover the whole IOMMU table is too strict. IOMMU allocators should handle mask constraint properly for each allocation. The patch enables to use old AirPort Extreme cards on PowerMacs with more than 1GB of memory; without the patch the driver init fails with: b43-pci-bridge 0001:01:01.0: Warning: IOMMU window too big for device mask b43-pci-bridge 0001:01:01.0: mask: 0x3fffffff, table end: 0x80000000 b43-phy0 ERROR: The machine/kernel does not support the required 30-bit DMA mask Signed-off-by: Aaro Koskinen --- arch/powerpc/kernel/dma-iommu.c | 9 ++++----- 1 files changed, 4 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/kernel/dma-iommu.c b/arch/powerpc/kernel/dma-iommu.c index 2d7bb8c..e489752 100644 --- a/arch/powerpc/kernel/dma-iommu.c +++ b/arch/powerpc/kernel/dma-iommu.c @@ -83,11 +83,10 @@ static int dma_iommu_dma_supported(struct device *dev, u64 mask) return 0; } - if ((tbl->it_offset + tbl->it_size) > (mask >> IOMMU_PAGE_SHIFT)) { - dev_info(dev, "Warning: IOMMU window too big for device mask\n"); - dev_info(dev, "mask: 0x%08llx, table end: 0x%08lx\n", - mask, (tbl->it_offset + tbl->it_size) << - IOMMU_PAGE_SHIFT); + if (tbl->it_offset > (mask >> IOMMU_PAGE_SHIFT)) { + dev_info(dev, "Warning: IOMMU offset too big for device mask\n"); + dev_info(dev, "mask: 0x%08llx, table offset: 0x%08lx\n", + mask, tbl->it_offset << IOMMU_PAGE_SHIFT); return 0; } else return 1; -- 1.7.2.5 -- 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/