From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sinan Kaya Subject: Re: [PATCH V3 1/3] ACPI, PCI IRQ: add PCI_USING penalty for ISA interrupts Date: Mon, 24 Oct 2016 00:16:04 -0400 Message-ID: <5299d939-5d7d-05b7-bd5a-df1fe213fb21@codeaurora.org> References: <1476505867-24599-1-git-send-email-okaya@codeaurora.org> <1476505867-24599-2-git-send-email-okaya@codeaurora.org> <20161022235837.GA1668@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20161022235837.GA1668@localhost> Sender: linux-kernel-owner@vger.kernel.org To: Bjorn Helgaas Cc: linux-acpi@vger.kernel.org, rjw@rjwysocki.net, bhelgaas@google.com, ravikanth.nalla@hpe.com, linux@rainbow-software.org, timur@codeaurora.org, cov@codeaurora.org, jcm@redhat.com, alex.williamson@redhat.com, linux-pci@vger.kernel.org, agross@codeaurora.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, wim@djo.tudelft.nl, linux-arm-kernel@lists.infradead.org, Len Brown List-Id: linux-arm-msm@vger.kernel.org On 10/22/2016 7:58 PM, Bjorn Helgaas wrote: > On Sat, Oct 15, 2016 at 12:31:05AM -0400, Sinan Kaya wrote: >> The change introduced in commit 103544d86976 ("ACPI,PCI,IRQ: reduce >> resource requirements") removed PCI_USING penalty from >> acpi_pci_link_allocate function as there is no longer a fixed size penalty >> array for both PCI interrupts greater than 16. >> >> The array size has been reduced to 16 and array name got prefixed as ISA >> since it only is accountable for the ISA interrupts. >> >> The original change in commit 103544d86976 ("ACPI,PCI,IRQ: reduce >> resource requirements") removed penalty assignment in the code for PCI >> thinking that we will add the penalty later in acpi_irq_pci_sharing_penalty >> function. >> >> However, this function only gets called if the IRQ number is greater than >> 16 and acpi_irq_get_penalty function gets called before ACPI start in >> acpi_isa_irq_available and acpi_penalize_isa_irq functions. We can't rely >> on iterating the link list. >> >> We need to add the PCI_USING penalty for ISA interrupts too if the link is >> in use and matches our ISA IRQ number. > > I think the history about the array size is more than is necessary for this > changelog. I think the useful part is something like this: > > ACPI: pci_link: Include PIRQ_PENALTY_PCI_USING for ISA IRQs > > 103544d86976 ("ACPI,PCI,IRQ: reduce resource requirements") replaced > the addition of PIRQ_PENALTY_PCI_USING in acpi_pci_link_allocate() > with an addition in acpi_irq_pci_sharing_penalty(), but f7eca374f000 > ("ACPI,PCI,IRQ: separate ISA penalty calculation") removed the use > of acpi_irq_pci_sharing_penalty() for ISA IRQs. > > Therefore, PIRQ_PENALTY_PCI_USING is missing from ISA IRQs used by > interrupt links. Include that penalty by adding it in the > acpi_pci_link_allocate() path. > > Fixes: f7eca374f000 ("ACPI,PCI,IRQ: separate ISA penalty calculation") > >> Signed-off-by: Sinan Kaya > > Acked-by: Bjorn Helgaas OK. Updated as suggested. > >> --- >> drivers/acpi/pci_link.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/drivers/acpi/pci_link.c b/drivers/acpi/pci_link.c >> index c983bf7..a212709 100644 >> --- a/drivers/acpi/pci_link.c >> +++ b/drivers/acpi/pci_link.c >> @@ -619,6 +619,10 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link) >> acpi_device_bid(link->device)); >> return -ENODEV; >> } else { >> + if (link->irq.active < ACPI_MAX_ISA_IRQS) >> + acpi_isa_irq_penalty[link->irq.active] += >> + PIRQ_PENALTY_PCI_USING; >> + >> printk(KERN_WARNING PREFIX "%s [%s] enabled at IRQ %d\n", >> acpi_device_name(link->device), >> acpi_device_bid(link->device), link->irq.active); >> -- >> 1.9.1 >> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel@lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.