1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright 2007, Olof Johansson, PA Semi
5 * Based on arch/powerpc/sysdev/mpic_u3msi.c:
7 * Copyright 2006, Segher Boessenkool, IBM Corporation.
8 * Copyright 2006-2007, Michael Ellerman, IBM Corporation.
11 #include <linux/irq.h>
12 #include <linux/irqdomain.h>
13 #include <linux/msi.h>
15 #include <asm/hw_irq.h>
16 #include <asm/ppc-pci.h>
17 #include <asm/msi_bitmap.h>
19 #include <sysdev/mpic.h>
21 /* Allocate 16 interrupts per device, to give an alignment of 16,
22 * since that's the size of the grouping w.r.t. affinity. If someone
23 * needs more than 32 MSI's down the road we'll have to rethink this,
24 * but it should be OK for now.
26 #define ALLOC_CHUNK 16
28 #define PASEMI_MSI_ADDR 0xfc080000
30 /* A bit ugly, can we get this from the pci_dev somehow? */
31 static struct mpic *msi_mpic;
34 static void mpic_pasemi_msi_mask_irq(struct irq_data *data)
36 pr_debug("mpic_pasemi_msi_mask_irq %d\n", data->irq);
37 pci_msi_mask_irq(data);
41 static void mpic_pasemi_msi_unmask_irq(struct irq_data *data)
43 pr_debug("mpic_pasemi_msi_unmask_irq %d\n", data->irq);
44 mpic_unmask_irq(data);
45 pci_msi_unmask_irq(data);
48 static struct irq_chip mpic_pasemi_msi_chip = {
49 .irq_shutdown = mpic_pasemi_msi_mask_irq,
50 .irq_mask = mpic_pasemi_msi_mask_irq,
51 .irq_unmask = mpic_pasemi_msi_unmask_irq,
52 .irq_eoi = mpic_end_irq,
53 .irq_set_type = mpic_set_irq_type,
54 .irq_set_affinity = mpic_set_affinity,
58 static void pasemi_msi_teardown_msi_irqs(struct pci_dev *pdev)
60 struct msi_desc *entry;
61 irq_hw_number_t hwirq;
63 pr_debug("pasemi_msi_teardown_msi_irqs, pdev %p\n", pdev);
65 msi_for_each_desc(entry, &pdev->dev, MSI_DESC_ASSOCIATED) {
66 hwirq = virq_to_hw(entry->irq);
67 irq_set_msi_desc(entry->irq, NULL);
68 irq_dispose_mapping(entry->irq);
70 msi_bitmap_free_hwirqs(&msi_mpic->msi_bitmap, hwirq, ALLOC_CHUNK);
74 static int pasemi_msi_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
77 struct msi_desc *entry;
81 if (type == PCI_CAP_ID_MSIX)
82 pr_debug("pasemi_msi: MSI-X untested, trying anyway\n");
83 pr_debug("pasemi_msi_setup_msi_irqs, pdev %p nvec %d type %d\n",
87 msg.address_lo = PASEMI_MSI_ADDR;
89 msi_for_each_desc(entry, &pdev->dev, MSI_DESC_NOTASSOCIATED) {
90 /* Allocate 16 interrupts for now, since that's the grouping for
91 * affinity. This can be changed later if it turns out 32 is too
92 * few MSIs for someone, but restrictions will apply to how the
93 * sources can be changed independently.
95 hwirq = msi_bitmap_alloc_hwirqs(&msi_mpic->msi_bitmap,
98 pr_debug("pasemi_msi: failed allocating hwirq\n");
102 virq = irq_create_mapping(msi_mpic->irqhost, hwirq);
104 pr_debug("pasemi_msi: failed mapping hwirq 0x%x\n",
106 msi_bitmap_free_hwirqs(&msi_mpic->msi_bitmap, hwirq,
111 /* Vector on MSI is really an offset, the hardware adds
112 * it to the value written at the magic address. So set
113 * it to 0 to remain sane.
115 mpic_set_vector(virq, 0);
117 irq_set_msi_desc(virq, entry);
118 irq_set_chip(virq, &mpic_pasemi_msi_chip);
119 irq_set_irq_type(virq, IRQ_TYPE_EDGE_RISING);
121 pr_debug("pasemi_msi: allocated virq 0x%x (hw 0x%x) " \
122 "addr 0x%x\n", virq, hwirq, msg.address_lo);
124 /* Likewise, the device writes [0...511] into the target
125 * register to generate MSI [512...1023]
127 msg.data = hwirq-0x200;
128 pci_write_msi_msg(virq, &msg);
134 int __init mpic_pasemi_msi_init(struct mpic *mpic)
137 struct pci_controller *phb;
138 struct device_node *of_node;
140 of_node = irq_domain_get_of_node(mpic->irqhost);
142 !of_device_is_compatible(of_node,
143 "pasemi,pwrficient-openpic"))
146 rc = mpic_msi_init_allocator(mpic);
148 pr_debug("pasemi_msi: Error allocating bitmap!\n");
152 pr_debug("pasemi_msi: Registering PA Semi MPIC MSI callbacks\n");
155 list_for_each_entry(phb, &hose_list, list_node) {
156 WARN_ON(phb->controller_ops.setup_msi_irqs);
157 phb->controller_ops.setup_msi_irqs = pasemi_msi_setup_msi_irqs;
158 phb->controller_ops.teardown_msi_irqs = pasemi_msi_teardown_msi_irqs;