Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932188AbbDIWkY (ORCPT ); Thu, 9 Apr 2015 18:40:24 -0400 Received: from mail-qk0-f175.google.com ([209.85.220.175]:33662 "EHLO mail-qk0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755650AbbDIWkU (ORCPT ); Thu, 9 Apr 2015 18:40:20 -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: Bjorn Helgaas Date: Thu, 9 Apr 2015 17:39:58 -0500 Message-ID: Subject: Re: [PATCH v3 1/4] PCI: X-Gene: Add the APM X-Gene v1 PCIe MSI/MSIX termination driver To: Duc Dang 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: 5168 Lines: 139 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. >>> + 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/