From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [103.22.144.67]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 130A41A167D for ; Thu, 2 Oct 2014 13:17:00 +1000 (EST) In-Reply-To: <1412073306-13812-9-git-send-email-mikey@neuling.org> To: Michael Neuling , greg@kroah.com, arnd@arndb.de, benh@kernel.crashing.org From: Michael Ellerman Subject: Re: [PATCH v2 08/17] powerpc/powerpc: Add new PCIe functions for allocating cxl interrupts Message-Id: <20141002031659.DB564140188@ozlabs.org> Date: Thu, 2 Oct 2014 13:16:59 +1000 (EST) Cc: cbe-oss-dev@lists.ozlabs.org, mikey@neuling.org, "Aneesh Kumar K.V" , imunsie@au.ibm.com, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, jk@ozlabs.org, anton@samba.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, 2014-30-09 at 10:34:57 UTC, Michael Neuling wrote: > From: Ian Munsie > > This adds a number of functions for allocating IRQs under powernv PCIe for cxl. > > diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c > index 329164f..b0b96f0 100644 > --- a/arch/powerpc/platforms/powernv/pci-ioda.c > +++ b/arch/powerpc/platforms/powernv/pci-ioda.c > @@ -503,6 +505,138 @@ static struct pnv_ioda_pe *pnv_ioda_get_pe(struct pci_dev *dev) > return NULL; > return &phb->ioda.pe_array[pdn->pe_number]; > } > + > +struct device_node *pnv_pci_to_phb_node(struct pci_dev *dev) > +{ > + struct pci_controller *hose = pci_bus_to_host(dev->bus); > + > + return hose->dn; > +} > +EXPORT_SYMBOL(pnv_pci_to_phb_node); > + > +#ifdef CONFIG_CXL_BASE > +int pnv_phb_to_cxl(struct pci_dev *dev) > +{ > + struct pci_controller *hose = pci_bus_to_host(dev->bus); > + struct pnv_phb *phb = hose->private_data; > + struct pnv_ioda_pe *pe; > + int rc; > + > + if (!(pe = pnv_ioda_get_pe(dev))) { > + rc = -ENODEV; > + goto out; > + } That'd be a lot simpler as: pe = pnv_ioda_get_pe(dev); if (!pe) return -ENODEV; > + pe_info(pe, "switch PHB to CXL\n"); > + pe_info(pe, "PHB-ID : 0x%016llx\n", phb->opal_id); > + pe_info(pe, " pe : %i\n", pe->pe_number); Spacing is a bit weird but maybe it matches something else? > + > + if ((rc = opal_pci_set_phb_cxl_mode(phb->opal_id, 1, pe->pe_number))) > + dev_err(&dev->dev, "opal_pci_set_phb_cxl_mode failed: %i\n", rc); Again why not: rc = opal_pci_set_phb_cxl_mode(phb->opal_id, 1, pe->pe_number); if (rc) dev_err(&dev->dev, "opal_pci_set_phb_cxl_mode failed: %i\n", rc); > +out: > + return rc; > +} > +EXPORT_SYMBOL(pnv_phb_to_cxl); > + > +int pnv_cxl_alloc_hwirq_ranges(struct cxl_irq_ranges *irqs, > + struct pci_dev *dev, int num) This could use some documentation. It seems to be that it allocates num irqs in some number of ranges, up to CXL_IRQ_RANGES? > +{ > + struct pci_controller *hose = pci_bus_to_host(dev->bus); > + struct pnv_phb *phb = hose->private_data; > + int range = 0; You reinitialise to 1 below? > + int hwirq; > + int try; So these can be: int hwirq, try, range; > + memset(irqs, 0, sizeof(struct cxl_irq_ranges)); > + > + for (range = 1; range < CXL_IRQ_RANGES && num; range++) { I think this would be clearer if range was just called "i" as usual. Why does it start at 1 ? > + try = num; > + while (try) { > + hwirq = msi_bitmap_alloc_hwirqs(&phb->msi_bmp, try); > + if (hwirq >= 0) > + break; > + try /= 2; > + } > + if (!try) > + goto fail; > + > + irqs->offset[range] = phb->msi_base + hwirq; > + irqs->range[range] = try; irqs->range is irq_hw_number_t but looks like it should just be uint. > + pr_devel("cxl alloc irq range 0x%x: offset: 0x%lx limit: %li\n", > + range, irqs->offset[range], irqs->range[range]); > + num -= try; > + } > + if (num) > + goto fail; > + > + return 0; > +fail: > + for (range--; range >= 0; range--) { > + hwirq = irqs->offset[range] - phb->msi_base; > + msi_bitmap_free_hwirqs(&phb->msi_bmp, hwirq, > + irqs->range[range]); > + irqs->range[range] = 0; > + } Because you zero ranges at the top I think you can replace all of the fail logic with a call to pnv_cxl_release_hwirq_ranges(). > + return -ENOSPC; > +} > +EXPORT_SYMBOL(pnv_cxl_alloc_hwirq_ranges); > + > +void pnv_cxl_release_hwirq_ranges(struct cxl_irq_ranges *irqs, > + struct pci_dev *dev) > +{ > + struct pci_controller *hose = pci_bus_to_host(dev->bus); > + struct pnv_phb *phb = hose->private_data; > + int range = 0; Unnecessary init again. > + int hwirq; > + > + for (range = 0; range < 4; range++) { Shouldn't 4 be CXL_IRQ_RANGES ? > + hwirq = irqs->offset[range] - phb->msi_base; That should be inside the if. Or better do: if (!irqs->range[range]) continue; ... > + if (irqs->range[range]) { > + pr_devel("cxl release irq range 0x%x: offset: 0x%lx limit: %ld\n", > + range, irqs->offset[range], > + irqs->range[range]); > + msi_bitmap_free_hwirqs(&phb->msi_bmp, hwirq, > + irqs->range[range]); > + } > + } > +} > +EXPORT_SYMBOL(pnv_cxl_release_hwirq_ranges); > + > +int pnv_cxl_get_irq_count(struct pci_dev *dev) > +{ > + struct pci_controller *hose = pci_bus_to_host(dev->bus); > + struct pnv_phb *phb = hose->private_data; Indentation is fubar. > + return phb->msi_bmp.irq_count; > +} > +EXPORT_SYMBOL(pnv_cxl_get_irq_count); > + > +#endif /* CONFIG_CXL_BASE */ > #endif /* CONFIG_PCI_MSI */ > > static int pnv_ioda_configure_pe(struct pnv_phb *phb, struct pnv_ioda_pe *pe) > @@ -1330,6 +1464,33 @@ static void set_msi_irq_chip(struct pnv_phb *phb, unsigned int virq) > irq_set_chip(virq, &phb->ioda.irq_chip); > } > > +#ifdef CONFIG_CXL_BASE Why is this here and not in the previous #ifdef CONFIG_CXL_BASE block ? > +int pnv_cxl_ioda_msi_setup(struct pci_dev *dev, unsigned int hwirq, > + unsigned int virq) > +{ > + struct pci_controller *hose = pci_bus_to_host(dev->bus); > + struct pnv_phb *phb = hose->private_data; > + unsigned int xive_num = hwirq - phb->msi_base; > + struct pnv_ioda_pe *pe; > + int rc; > + > + if (!(pe = pnv_ioda_get_pe(dev))) > + return -ENODEV; > + > + /* Assign XIVE to PE */ > + rc = opal_pci_set_xive_pe(phb->opal_id, pe->pe_number, xive_num); > + if (rc) { > + pr_warn("%s: OPAL error %d setting msi_base 0x%x hwirq 0x%x XIVE 0x%x PE\n", > + pci_name(dev), rc, phb->msi_base, hwirq, xive_num); dev_warn() ? cheers