Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753415AbdFMOB2 convert rfc822-to-8bit (ORCPT ); Tue, 13 Jun 2017 10:01:28 -0400 Received: from us-smtp-delivery-107.mimecast.com ([216.205.24.107]:30857 "EHLO us-smtp-delivery-107.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752326AbdFMOB1 (ORCPT ); Tue, 13 Jun 2017 10:01:27 -0400 Subject: [PATCH v6 3/3] PCI: Add tango MSI controller support To: Marc Zyngier , Thomas Gleixner CC: Bjorn Helgaas , Robin Murphy , Lorenzo Pieralisi , Liviu Dudau , David Laight , linux-pci , Linux ARM , LKML , Mason References: <741766e5-cff2-db5f-d40b-6866e08fd966@sigmadesigns.com> <9975fa6c-f426-519b-6b3e-a2d102d36fd5@arm.com> From: Marc Gonzalez Message-ID: <82d6bf37-96b9-cd9d-134b-f01638fa2b1b@sigmadesigns.com> Date: Tue, 13 Jun 2017 16:01:14 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0 SeaMonkey/2.49 MIME-Version: 1.0 In-Reply-To: <9975fa6c-f426-519b-6b3e-a2d102d36fd5@arm.com> X-Originating-IP: [172.27.0.114] X-MC-Unique: ldZ23pFYNGCciLvIKHbLKg-3 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7362 Lines: 281 The MSI controller in Tango supports 256 message-signaled interrupts, and a single doorbell address. Signed-off-by: Marc Gonzalez --- Changes from v5 to v6 o Rename 'used' bitmap to 'used_msi' o Rename 'lock' spinlock to 'used_msi_lock' o Take lock in interrupt handler o Remove irq_dom in error path --- drivers/pci/host/pcie-tango.c | 225 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 225 insertions(+) diff --git a/drivers/pci/host/pcie-tango.c b/drivers/pci/host/pcie-tango.c index 67aaadcc1c5e..b06446b23bc8 100644 --- a/drivers/pci/host/pcie-tango.c +++ b/drivers/pci/host/pcie-tango.c @@ -1,16 +1,228 @@ +#include +#include #include #include +#include #include #define MSI_MAX 256 #define SMP8759_MUX 0x48 #define SMP8759_TEST_OUT 0x74 +#define SMP8759_STATUS 0x80 +#define SMP8759_ENABLE 0xa0 +#define SMP8759_DOORBELL 0xa002e07c struct tango_pcie { + DECLARE_BITMAP(used_msi, MSI_MAX); + spinlock_t used_msi_lock; void __iomem *mux; + void __iomem *msi_status; + void __iomem *msi_enable; + phys_addr_t msi_doorbell; + struct irq_domain *irq_dom; + struct irq_domain *msi_dom; + int irq; }; +/*** MSI CONTROLLER SUPPORT ***/ + +static void tango_msi_isr(struct irq_desc *desc) +{ + struct irq_chip *chip = irq_desc_get_chip(desc); + struct tango_pcie *pcie = irq_desc_get_handler_data(desc); + unsigned long flags, status, base, virq, idx, pos = 0; + + chained_irq_enter(chip, desc); + spin_lock_irqsave(&pcie->used_msi_lock, flags); + + while ((pos = find_next_bit(pcie->used_msi, MSI_MAX, pos)) < MSI_MAX) { + base = round_down(pos, 32); + status = readl_relaxed(pcie->msi_status + base / 8); + for_each_set_bit(idx, &status, 32) { + virq = irq_find_mapping(pcie->irq_dom, base + idx); + generic_handle_irq(virq); + } + pos = base + 32; + } + + spin_unlock_irqrestore(&pcie->used_msi_lock, flags); + chained_irq_exit(chip, desc); +} + +static void tango_ack(struct irq_data *d) +{ + struct tango_pcie *pcie = d->chip_data; + u32 offset = (d->hwirq / 32) * 4; + u32 bit = BIT(d->hwirq % 32); + + writel_relaxed(bit, pcie->msi_status + offset); +} + +static void update_msi_enable(struct irq_data *d, bool unmask) +{ + unsigned long flags; + struct tango_pcie *pcie = d->chip_data; + u32 offset = (d->hwirq / 32) * 4; + u32 bit = BIT(d->hwirq % 32); + u32 val; + + spin_lock_irqsave(&pcie->used_msi_lock, flags); + val = readl_relaxed(pcie->msi_enable + offset); + val = unmask ? val | bit : val & ~bit; + writel_relaxed(val, pcie->msi_enable + offset); + spin_unlock_irqrestore(&pcie->used_msi_lock, flags); +} + +static void tango_mask(struct irq_data *d) +{ + update_msi_enable(d, false); +} + +static void tango_unmask(struct irq_data *d) +{ + update_msi_enable(d, true); +} + +static int tango_set_affinity(struct irq_data *d, + const struct cpumask *mask, bool force) +{ + return -EINVAL; +} + +static void tango_compose_msi_msg(struct irq_data *d, struct msi_msg *msg) +{ + struct tango_pcie *pcie = d->chip_data; + msg->address_lo = lower_32_bits(pcie->msi_doorbell); + msg->address_hi = upper_32_bits(pcie->msi_doorbell); + msg->data = d->hwirq; +} + +static struct irq_chip tango_chip = { + .irq_ack = tango_ack, + .irq_mask = tango_mask, + .irq_unmask = tango_unmask, + .irq_set_affinity = tango_set_affinity, + .irq_compose_msi_msg = tango_compose_msi_msg, +}; + +static void msi_ack(struct irq_data *d) +{ + irq_chip_ack_parent(d); +} + +static void msi_mask(struct irq_data *d) +{ + pci_msi_mask_irq(d); + irq_chip_mask_parent(d); +} + +static void msi_unmask(struct irq_data *d) +{ + pci_msi_unmask_irq(d); + irq_chip_unmask_parent(d); +} + +static struct irq_chip msi_chip = { + .name = "MSI", + .irq_ack = msi_ack, + .irq_mask = msi_mask, + .irq_unmask = msi_unmask, +}; + +static struct msi_domain_info msi_dom_info = { + .flags = MSI_FLAG_PCI_MSIX + | MSI_FLAG_USE_DEF_DOM_OPS + | MSI_FLAG_USE_DEF_CHIP_OPS, + .chip = &msi_chip, +}; + +static int tango_irq_domain_alloc(struct irq_domain *dom, + unsigned int virq, unsigned int nr_irqs, void *args) +{ + unsigned long flags; + int pos, err = -ENOSPC; + struct tango_pcie *pcie = dom->host_data; + + spin_lock_irqsave(&pcie->used_msi_lock, flags); + pos = find_first_zero_bit(pcie->used_msi, MSI_MAX); + if (pos < MSI_MAX) { + err = 0; + __set_bit(pos, pcie->used_msi); + irq_domain_set_info(dom, virq, pos, + &tango_chip, pcie, handle_edge_irq, NULL, NULL); + } + spin_unlock_irqrestore(&pcie->used_msi_lock, flags); + + return err; +} + +static void tango_irq_domain_free(struct irq_domain *dom, + unsigned int virq, unsigned int nr_irqs) +{ + unsigned long flags; + struct irq_data *d = irq_domain_get_irq_data(dom, virq); + struct tango_pcie *pcie = d->chip_data; + + spin_lock_irqsave(&pcie->used_msi_lock, flags); + __clear_bit(d->hwirq, pcie->used_msi); + spin_unlock_irqrestore(&pcie->used_msi_lock, flags); +} + +static const struct irq_domain_ops irq_dom_ops = { + .alloc = tango_irq_domain_alloc, + .free = tango_irq_domain_free, +}; + +static int tango_msi_remove(struct platform_device *pdev) +{ + struct tango_pcie *pcie = platform_get_drvdata(pdev); + + irq_set_chained_handler_and_data(pcie->irq, NULL, NULL); + irq_domain_remove(pcie->msi_dom); + irq_domain_remove(pcie->irq_dom); + + return 0; +} + +static int tango_msi_probe(struct platform_device *pdev, struct tango_pcie *pcie) +{ + int i, virq; + struct irq_domain *msi_dom, *irq_dom; + struct fwnode_handle *fwnode = of_node_to_fwnode(pdev->dev.of_node); + + spin_lock_init(&pcie->used_msi_lock); + for (i = 0; i < MSI_MAX / 32; ++i) + writel_relaxed(0, pcie->msi_enable + i * 4); + + virq = platform_get_irq(pdev, 1); + if (virq <= 0) { + pr_err("Failed to map IRQ\n"); + return -ENXIO; + } + + irq_dom = irq_domain_create_linear(fwnode, MSI_MAX, &irq_dom_ops, pcie); + if (!irq_dom) { + pr_err("Failed to create IRQ domain\n"); + return -ENOMEM; + } + + msi_dom = pci_msi_create_irq_domain(fwnode, &msi_dom_info, irq_dom); + if (!msi_dom) { + pr_err("Failed to create MSI domain\n"); + irq_domain_remove(irq_dom); + return -ENOMEM; + } + + pcie->irq_dom = irq_dom; + pcie->msi_dom = msi_dom; + pcie->irq = virq; + + irq_set_chained_handler_and_data(virq, tango_msi_isr, pcie); + + return 0; +} + /*** HOST BRIDGE SUPPORT ***/ static int smp8759_config_read(struct pci_bus *bus, @@ -88,6 +300,9 @@ static int tango_check_pcie_link(void __iomem *test_out) static int smp8759_init(struct tango_pcie *pcie, void __iomem *base) { pcie->mux = base + SMP8759_MUX; + pcie->msi_status = base + SMP8759_STATUS; + pcie->msi_enable = base + SMP8759_ENABLE; + pcie->msi_doorbell = SMP8759_DOORBELL; return tango_check_pcie_link(base + SMP8759_TEST_OUT); } @@ -121,11 +336,21 @@ static int tango_pcie_probe(struct platform_device *pdev) if (ret) return ret; + ret = tango_msi_probe(pdev, pcie); + if (ret) + return ret; + return pci_host_common_probe(pdev, &smp8759_ecam_ops); } +static int tango_pcie_remove(struct platform_device *pdev) +{ + return tango_msi_remove(pdev); +} + static struct platform_driver tango_pcie_driver = { .probe = tango_pcie_probe, + .remove = tango_pcie_remove, .driver = { .name = KBUILD_MODNAME, .of_match_table = tango_pcie_ids, -- 2.11.0