From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp05.au.ibm.com ([202.81.31.147]:59202 "EHLO e23smtp05.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752682AbbHFENR (ORCPT ); Thu, 6 Aug 2015 00:13:17 -0400 Received: from /spool/local by e23smtp05.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 6 Aug 2015 14:13:15 +1000 From: Gavin Shan To: linuxppc-dev@lists.ozlabs.org Cc: linux-pci@vger.kernel.org, devicetree@vger.kernel.org, benh@kernel.crashing.org, mpe@ellerman.id.au, bhelgaas@google.com, grant.likely@linaro.org, robherring2@gmail.com, panto@antoniou-consulting.com, aik@ozlabs.ru, Gavin Shan Subject: [PATCH v6 18/42] powerpc/powernv: Allocate PE# in deasending order Date: Thu, 6 Aug 2015 14:11:23 +1000 Message-Id: <1438834307-26960-19-git-send-email-gwshan@linux.vnet.ibm.com> In-Reply-To: <1438834307-26960-1-git-send-email-gwshan@linux.vnet.ibm.com> References: <1438834307-26960-1-git-send-email-gwshan@linux.vnet.ibm.com> Sender: linux-pci-owner@vger.kernel.org List-ID: The available PE#, represented by a bitmap in the PHB, is allocated in ascending order. It conflicts with the fact that M64 segments are assigned in same order. In order to avoid the conflict, the patch allocates PE# in descending order. Signed-off-by: Gavin Shan --- arch/powerpc/platforms/powernv/pci-ioda.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c index 56b058c..1c950e8 100644 --- a/arch/powerpc/platforms/powernv/pci-ioda.c +++ b/arch/powerpc/platforms/powernv/pci-ioda.c @@ -161,13 +161,18 @@ static struct pnv_ioda_pe *pnv_ioda_reserve_pe(struct pnv_phb *phb, int pe_no) static struct pnv_ioda_pe *pnv_ioda_alloc_pe(struct pnv_phb *phb) { unsigned long pe; + unsigned long limit = phb->ioda.total_pe_num - 1; do { pe = find_next_zero_bit(phb->ioda.pe_alloc, - phb->ioda.total_pe_num, 0); - if (pe >= phb->ioda.total_pe_num) + phb->ioda.total_pe_num, limit); + if (pe < phb->ioda.total_pe_num && + !test_and_set_bit(pe, phb->ioda.pe_alloc)) + break; + + if (--limit >= phb->ioda.total_pe_num) return NULL; - } while(test_and_set_bit(pe, phb->ioda.pe_alloc)); + } while (1); return pnv_ioda_init_pe(phb, pe); } -- 2.1.0