From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f48.google.com ([209.85.220.48]:35438 "EHLO mail-pa0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751532AbbKQBHZ (ORCPT ); Mon, 16 Nov 2015 20:07:25 -0500 Received: by pacej9 with SMTP id ej9so85566144pac.2 for ; Mon, 16 Nov 2015 17:07:24 -0800 (PST) Subject: Re: [PATCH v7 17/50] powerpc/powernv: Avoid calculating DMA32 segments on PHB3 To: Gavin Shan , linuxppc-dev@lists.ozlabs.org References: <1446642770-4681-1-git-send-email-gwshan@linux.vnet.ibm.com> <1446642770-4681-18-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, bhelgaas@google.com, grant.likely@linaro.org, robherring2@gmail.com, panto@antoniou-consulting.com, frowand.list@gmail.com From: Alexey Kardashevskiy Message-ID: <564A7DC5.5060702@ozlabs.ru> Date: Tue, 17 Nov 2015 12:07:17 +1100 MIME-Version: 1.0 In-Reply-To: <1446642770-4681-18-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 11/05/2015 12:12 AM, Gavin Shan wrote: > In pnv_ioda_setup_dma(), it's unnecessary to calculate the DMA32 > segments for PEs on PHB3 as the whole available DMA32 space can > be assigned to one specific PE on PHB3. > > This splits pnv_ioda_setup_dma() to pnv_pci_ioda1_setup_dma() and > pnv_pci_ioda2_setup_dma() in order to avoid calculating DMA32 > segments for PEs on PHB3. No logical changes introduced. This patch is not needed as [PATCH v7 20/50] powerpc/powernv: Improve DMA32 segment calculation moves this calculation to another place (which already makes this patch unnecessary) and [PATCH v7 26/50] powerpc/powernv: Create PEs at PCI hot plugging time removes just introduced pnv_pci_ioda1_setup_dma() - if you remove it, then there is no point in fixing it in the first place. > > Signed-off-by: Gavin Shan > --- > arch/powerpc/platforms/powernv/pci-ioda.c | 41 ++++++++++++++++++------------- > 1 file changed, 24 insertions(+), 17 deletions(-) > > diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c > index 5a08e20..4c2e023 100644 > --- a/arch/powerpc/platforms/powernv/pci-ioda.c > +++ b/arch/powerpc/platforms/powernv/pci-ioda.c > @@ -2383,7 +2383,7 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb, > pnv_ioda_setup_bus_dma(pe, pe->pbus); > } > > -static void pnv_ioda_setup_dma(struct pnv_phb *phb) > +static void pnv_pci_ioda1_setup_dma(struct pnv_phb *phb) > { > struct pci_controller *hose = phb->hose; > unsigned int residual, remaining, segs, tw, base; > @@ -2428,26 +2428,30 @@ static void pnv_ioda_setup_dma(struct pnv_phb *phb) > segs = remaining; > } > > - /* > - * For IODA2 compliant PHB3, we needn't care about the weight. > - * The all available 32-bits DMA space will be assigned to > - * the specific PE. > - */ > - if (phb->type == PNV_PHB_IODA1) { > - pe_info(pe, "DMA weight %d, assigned %d DMA32 segments\n", > - pe->dma_weight, segs); > - pnv_pci_ioda1_setup_dma_pe(phb, pe, base, segs); > - } else { > - pe_info(pe, "Assign DMA32 space\n"); > - segs = 0; > - pnv_pci_ioda2_setup_dma_pe(phb, pe); > - } > + pe_info(pe, "DMA weight %d, assigned %d DMA32 segments\n", > + pe->dma_weight, segs); > + pnv_pci_ioda1_setup_dma_pe(phb, pe, base, segs); > > remaining -= segs; > base += segs; > } > } > > +static void pnv_pci_ioda2_setup_dma(struct pnv_phb *phb) > +{ > + struct pnv_ioda_pe *pe; > + > + pnv_pci_ioda_setup_opal_tce_kill(phb); > + > + list_for_each_entry(pe, &phb->ioda.pe_dma_list, dma_link) { > + if (!pe->dma_weight) > + continue; > + > + pe_info(pe, "Assign DMA32 space\n"); > + pnv_pci_ioda2_setup_dma_pe(phb, pe); > + } > +} > + > #ifdef CONFIG_PCI_MSI > static void pnv_ioda2_msi_eoi(struct irq_data *d) > { > @@ -2931,10 +2935,13 @@ static void pnv_pci_ioda_setup_DMA(void) > struct pnv_phb *phb; > > list_for_each_entry_safe(hose, tmp, &hose_list, list_node) { > - pnv_ioda_setup_dma(hose->private_data); > + phb = hose->private_data; > + if (phb->type == PNV_PHB_IODA1) > + pnv_pci_ioda1_setup_dma(phb); > + else > + pnv_pci_ioda2_setup_dma(phb); > > /* Mark the PHB initialization done */ > - phb = hose->private_data; > phb->initialized = 1; > } > } > -- Alexey