Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755989AbbDIX0h (ORCPT ); Thu, 9 Apr 2015 19:26:37 -0400 Received: from exprod5og107.obsmtp.com ([64.18.0.184]:36709 "EHLO mail-vn0-f54.google.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754313AbbDIX0f (ORCPT ); Thu, 9 Apr 2015 19:26:35 -0400 MIME-Version: 1.0 In-Reply-To: References: <20150408084448.5f0793b7@why.wild-wind.fr.eu.org> <7923ef6ffd60a7c3de3c8c04fe746bbd3c15b5ac.1428564115.git.dhdang@apm.com> <20150409201115.GN30967@google.com> From: Duc Dang Date: Thu, 9 Apr 2015 16:26:04 -0700 Message-ID: Subject: Re: [PATCH v3 1/4] PCI: X-Gene: Add the APM X-Gene v1 PCIe MSI/MSIX termination driver To: Bjorn Helgaas Cc: Arnd Bergmann , Grant Likely , Liviu Dudau , Marc Zyngier , "linux-pci@vger.kernel.org" , linux-arm , "linux-kernel@vger.kernel.org" , Tanmay Inamdar , Loc Ho , Feng Kan Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5434 Lines: 147 On Thu, Apr 9, 2015 at 3:39 PM, Bjorn Helgaas wrote: > On Thu, Apr 9, 2015 at 4:52 PM, Duc Dang wrote: >> On Thu, Apr 9, 2015 at 1:11 PM, Bjorn Helgaas wrote: >>> On Thu, Apr 09, 2015 at 10:05:03AM -0700, Duc Dang wrote: >>>> X-Gene v1 SoC supports total 2688 MSI/MSIX vectors coalesced into >>>> 16 HW IRQ lines. >>>> >>>> Signed-off-by: Duc Dang >>>> Signed-off-by: Tanmay Inamdar >>>> ... >>> >>>> --- /dev/null >>>> +++ b/drivers/pci/host/pci-xgene-msi.c >>>> @@ -0,0 +1,407 @@ >>>> ... >>> >>>> +static void xgene_irq_domain_free(struct irq_domain *domain, >>>> + unsigned int virq, unsigned int nr_irqs) >>>> +{ >>>> + struct irq_data *d = irq_domain_get_irq_data(domain, virq); >>>> + struct xgene_msi *msi = irq_data_get_irq_chip_data(d); >>>> + >>>> + mutex_lock(&msi->bitmap_lock); >>>> + >>>> + if (!test_bit(d->hwirq, msi->bitmap)) >>>> + pr_err("trying to free unused MSI#%lu\n", d->hwirq); >>> >>> I'll let Marc comment on the substance of this patch, but I'd sure like to >>> see more information in this and the other pr_errs below. The text "failed >>> to create parent MSI domain" in the dmesg log is not enough. Ideally it >>> would identify the relevant host bridge. >>> >> Hi Bjorn, >> >> X-Gene has single MSI block that serves 5 PCIe ports. so in this >> implementation, 5 X-Gene PCIe host bridges share the same MSI domain. >> >> I can add X-Gene 1 MSI driver name and device tree node name into >> these messages, but the host bridge information is not available. >> >> As I understand, in case of error, the upper layer MSI core and driver >> code will check and report the error with additional device >> information (bus number, function number, etc)? > > If you think the upper layers already report the error, maybe you > could just drop the output from the X-Gene code. > > I just think it's pointless to print messages that are constant > strings with no hook for the user to associate them with a device or > event. Hi Bjorn, Yes, I will do so. Regards, Duc Dang. > >>>> + else >>>> + clear_bit(d->hwirq, msi->bitmap); >>>> + >>>> + mutex_unlock(&msi->bitmap_lock); >>>> + >>>> + irq_domain_free_irqs_parent(domain, virq, nr_irqs); >>>> +} >>>> + >>>> +static const struct irq_domain_ops msi_domain_ops = { >>>> + .alloc = xgene_irq_domain_alloc, >>>> + .free = xgene_irq_domain_free, >>>> +}; >>>> + >>>> +static int xgene_allocate_domains(struct xgene_msi *msi) >>>> +{ >>>> + msi->domain = irq_domain_add_linear(NULL, msi->settings->nr_msi_vec, >>>> + &msi_domain_ops, msi); >>>> + >>>> + if (!msi->domain) { >>>> + pr_err("failed to create parent MSI domain\n"); >>>> + return -ENOMEM; >>>> + } >>>> + >>>> + msi->mchip.of_node = msi->node; >>>> + msi->mchip.domain = pci_msi_create_irq_domain(msi->mchip.of_node, >>>> + &xgene_msi_domain_info, >>>> + msi->domain); >>>> + >>>> + if (!msi->mchip.domain) { >>>> + pr_err("failed to create MSI domain\n"); >>>> + irq_domain_remove(msi->domain); >>>> + return -ENOMEM; >>>> + } >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static void xgene_free_domains(struct xgene_msi *msi) >>>> +{ >>>> + if (msi->mchip.domain) >>>> + irq_domain_remove(msi->mchip.domain); >>>> + if (msi->domain) >>>> + irq_domain_remove(msi->domain); >>>> +} >>>> + >>>> +static int xgene_msi_init_allocator(struct xgene_msi *xgene_msi) >>>> +{ >>>> + u32 msi_irq_count = xgene_msi->settings->nr_msi_vec; >>>> + u32 hw_irq_count = xgene_msi->settings->nr_hw_irqs; >>>> + int size = BITS_TO_LONGS(msi_irq_count) * sizeof(long); >>>> + >>>> + xgene_msi->bitmap = kzalloc(size, GFP_KERNEL); >>>> + if (!xgene_msi->bitmap) >>>> + return -ENOMEM; >>>> + >>>> + mutex_init(&xgene_msi->bitmap_lock); >>>> + >>>> + xgene_msi->msi_virqs = kcalloc(hw_irq_count, sizeof(int), GFP_KERNEL); >>>> + if (!xgene_msi->msi_virqs) >>>> + return -ENOMEM; >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static irqreturn_t xgene_msi_isr(int irq, void *data) >>>> +{ >>>> + struct xgene_msi *xgene_msi = (struct xgene_msi *) data; >>>> + unsigned int virq; >>>> + int msir_index, msir_reg, msir_val, hw_irq; >>>> + u32 intr_index, grp_select, msi_grp, processed = 0; >>>> + u32 nr_hw_irqs, irqs_per_index, index_per_group; >>>> + >>>> + msi_grp = irq - xgene_msi->msi_virqs[0]; >>>> + if (msi_grp >= xgene_msi->settings->nr_hw_irqs) { >>>> + pr_err("invalid msi received\n"); >>>> + return IRQ_NONE; >>>> + } >>> >>> Bjorn >> -- >> 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/ -- 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/