From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f52.google.com ([209.85.220.52]:33118 "EHLO mail-pa0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933964AbcDMGVP (ORCPT ); Wed, 13 Apr 2016 02:21:15 -0400 Received: by mail-pa0-f52.google.com with SMTP id zm5so27816599pac.0 for ; Tue, 12 Apr 2016 23:21:14 -0700 (PDT) Subject: Re: [PATCH v8 08/45] powerpc/powernv: Fix initial IO and M32 segmap To: Gavin Shan , linuxppc-dev@lists.ozlabs.org References: <1455680668-23298-1-git-send-email-gwshan@linux.vnet.ibm.com> <1455680668-23298-9-git-send-email-gwshan@linux.vnet.ibm.com> Cc: linux-pci@vger.kernel.org, devicetree@vger.kernel.org, benh@kernel.crashing.org, mpe@ellerman.id.au, dja@axtens.net, bhelgaas@google.com, robherring2@gmail.com, grant.likely@linaro.org From: Alexey Kardashevskiy Message-ID: <570DE553.80708@ozlabs.ru> Date: Wed, 13 Apr 2016 16:21:07 +1000 MIME-Version: 1.0 In-Reply-To: <1455680668-23298-9-git-send-email-gwshan@linux.vnet.ibm.com> Content-Type: text/plain; charset=koi8-r; format=flowed Sender: linux-pci-owner@vger.kernel.org List-ID: On 02/17/2016 02:43 PM, Gavin Shan wrote: > There are two arrays for IO and M32 segment maps on every PHB. > The index of the arrays are segment number and the value stored > in the corresponding element is PE number, indicating the segment > is assigned to the PE. Initially, all elements in those two arrays > are zeroes, meaning all segments are assigned to PE#0. It's wrong. > > This fixes the initial values in the elements of those two arrays > to IODA_INVALID_PE, meaning all segments aren't assigned to any > PE. This is ok. > In order to use IODA_INVALID_PE (-1) to represent invalid PE > number, the types of those two arrays are changed from "unsigned int" > to "int". "unsigned" can carry (-1) perfectly fine, just add a type cast to IODA_INVALID_PE: #define IODA_INVALID_PE (unsigned int)(-1) Using "signed" type for indexes which cannot be negative does not make much sense - instead of checking for the upper boundary, you have to check for "< 0" too. OPAL uses unsigned type for PE (uint64_t or uint32_t or uint16_t - this is quite funny). pnv_ioda_pe::pe_number is "unsigned" and this pe_number is the same thing as I can see in pnv_ioda_setup_dev_PE(). Some printk() print the PE number as "%x" (which implies "unsigned"). I suggest changing the pci_dn::pe_number type from "int" to "unsigned int" to match pnv_ioda_pe::pe_number, in a separate patch. Or do not touch types for now. > Signed-off-by: Gavin Shan > --- > arch/powerpc/platforms/powernv/pci-ioda.c | 9 +++++++-- > arch/powerpc/platforms/powernv/pci.h | 4 ++-- > 2 files changed, 9 insertions(+), 4 deletions(-) > > diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c > index 1d2514f..44cc5f3 100644 > --- a/arch/powerpc/platforms/powernv/pci-ioda.c > +++ b/arch/powerpc/platforms/powernv/pci-ioda.c > @@ -3239,7 +3239,7 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np, > unsigned long size, m32map_off, pemap_off, iomap_off = 0; > const __be64 *prop64; > const __be32 *prop32; > - int len; > + int i, len; > u64 phb_id; > void *aux; > long rc; > @@ -3334,8 +3334,13 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np, > aux = memblock_virt_alloc(size, 0); > phb->ioda.pe_alloc = aux; > phb->ioda.m32_segmap = aux + m32map_off; > - if (phb->type == PNV_PHB_IODA1) > + for (i = 0; i < phb->ioda.total_pe_num; i++) > + phb->ioda.m32_segmap[i] = IODA_INVALID_PE; > + if (phb->type == PNV_PHB_IODA1) { > phb->ioda.io_segmap = aux + iomap_off; > + for (i = 0; i < phb->ioda.total_pe_num; i++) > + phb->ioda.io_segmap[i] = IODA_INVALID_PE; > + } > phb->ioda.pe_array = aux + pemap_off; > set_bit(phb->ioda.reserved_pe_idx, phb->ioda.pe_alloc); > > diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h > index 784882a..36c4965 100644 > --- a/arch/powerpc/platforms/powernv/pci.h > +++ b/arch/powerpc/platforms/powernv/pci.h > @@ -146,8 +146,8 @@ struct pnv_phb { > struct pnv_ioda_pe *pe_array; > > /* M32 & IO segment maps */ > - unsigned int *m32_segmap; > - unsigned int *io_segmap; > + int *m32_segmap; > + int *io_segmap; > > /* IRQ chip */ > int irq_chip_init; > -- Alexey