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-rw-r--r--arch/powerpc/platforms/pasemi/msi.c161
1 files changed, 161 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pasemi/msi.c b/arch/powerpc/platforms/pasemi/msi.c
new file mode 100644
index 000000000..dc1846660
--- /dev/null
+++ b/arch/powerpc/platforms/pasemi/msi.c
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2007, Olof Johansson, PA Semi
+ *
+ * Based on arch/powerpc/sysdev/mpic_u3msi.c:
+ *
+ * Copyright 2006, Segher Boessenkool, IBM Corporation.
+ * Copyright 2006-2007, Michael Ellerman, IBM Corporation.
+ */
+
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/msi.h>
+#include <asm/mpic.h>
+#include <asm/hw_irq.h>
+#include <asm/ppc-pci.h>
+#include <asm/msi_bitmap.h>
+
+#include <sysdev/mpic.h>
+
+/* Allocate 16 interrupts per device, to give an alignment of 16,
+ * since that's the size of the grouping w.r.t. affinity. If someone
+ * needs more than 32 MSI's down the road we'll have to rethink this,
+ * but it should be OK for now.
+ */
+#define ALLOC_CHUNK 16
+
+#define PASEMI_MSI_ADDR 0xfc080000
+
+/* A bit ugly, can we get this from the pci_dev somehow? */
+static struct mpic *msi_mpic;
+
+
+static void mpic_pasemi_msi_mask_irq(struct irq_data *data)
+{
+ pr_debug("mpic_pasemi_msi_mask_irq %d\n", data->irq);
+ pci_msi_mask_irq(data);
+ mpic_mask_irq(data);
+}
+
+static void mpic_pasemi_msi_unmask_irq(struct irq_data *data)
+{
+ pr_debug("mpic_pasemi_msi_unmask_irq %d\n", data->irq);
+ mpic_unmask_irq(data);
+ pci_msi_unmask_irq(data);
+}
+
+static struct irq_chip mpic_pasemi_msi_chip = {
+ .irq_shutdown = mpic_pasemi_msi_mask_irq,
+ .irq_mask = mpic_pasemi_msi_mask_irq,
+ .irq_unmask = mpic_pasemi_msi_unmask_irq,
+ .irq_eoi = mpic_end_irq,
+ .irq_set_type = mpic_set_irq_type,
+ .irq_set_affinity = mpic_set_affinity,
+ .name = "PASEMI-MSI",
+};
+
+static void pasemi_msi_teardown_msi_irqs(struct pci_dev *pdev)
+{
+ struct msi_desc *entry;
+ irq_hw_number_t hwirq;
+
+ pr_debug("pasemi_msi_teardown_msi_irqs, pdev %p\n", pdev);
+
+ msi_for_each_desc(entry, &pdev->dev, MSI_DESC_ASSOCIATED) {
+ hwirq = virq_to_hw(entry->irq);
+ irq_set_msi_desc(entry->irq, NULL);
+ irq_dispose_mapping(entry->irq);
+ msi_bitmap_free_hwirqs(&msi_mpic->msi_bitmap, hwirq, ALLOC_CHUNK);
+ }
+}
+
+static int pasemi_msi_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
+{
+ unsigned int virq;
+ struct msi_desc *entry;
+ struct msi_msg msg;
+ int hwirq;
+
+ if (type == PCI_CAP_ID_MSIX)
+ pr_debug("pasemi_msi: MSI-X untested, trying anyway\n");
+ pr_debug("pasemi_msi_setup_msi_irqs, pdev %p nvec %d type %d\n",
+ pdev, nvec, type);
+
+ msg.address_hi = 0;
+ msg.address_lo = PASEMI_MSI_ADDR;
+
+ msi_for_each_desc(entry, &pdev->dev, MSI_DESC_NOTASSOCIATED) {
+ /* Allocate 16 interrupts for now, since that's the grouping for
+ * affinity. This can be changed later if it turns out 32 is too
+ * few MSIs for someone, but restrictions will apply to how the
+ * sources can be changed independently.
+ */
+ hwirq = msi_bitmap_alloc_hwirqs(&msi_mpic->msi_bitmap,
+ ALLOC_CHUNK);
+ if (hwirq < 0) {
+ pr_debug("pasemi_msi: failed allocating hwirq\n");
+ return hwirq;
+ }
+
+ virq = irq_create_mapping(msi_mpic->irqhost, hwirq);
+ if (!virq) {
+ pr_debug("pasemi_msi: failed mapping hwirq 0x%x\n",
+ hwirq);
+ msi_bitmap_free_hwirqs(&msi_mpic->msi_bitmap, hwirq,
+ ALLOC_CHUNK);
+ return -ENOSPC;
+ }
+
+ /* Vector on MSI is really an offset, the hardware adds
+ * it to the value written at the magic address. So set
+ * it to 0 to remain sane.
+ */
+ mpic_set_vector(virq, 0);
+
+ irq_set_msi_desc(virq, entry);
+ irq_set_chip(virq, &mpic_pasemi_msi_chip);
+ irq_set_irq_type(virq, IRQ_TYPE_EDGE_RISING);
+
+ pr_debug("pasemi_msi: allocated virq 0x%x (hw 0x%x) " \
+ "addr 0x%x\n", virq, hwirq, msg.address_lo);
+
+ /* Likewise, the device writes [0...511] into the target
+ * register to generate MSI [512...1023]
+ */
+ msg.data = hwirq-0x200;
+ pci_write_msi_msg(virq, &msg);
+ }
+
+ return 0;
+}
+
+int __init mpic_pasemi_msi_init(struct mpic *mpic)
+{
+ int rc;
+ struct pci_controller *phb;
+ struct device_node *of_node;
+
+ of_node = irq_domain_get_of_node(mpic->irqhost);
+ if (!of_node ||
+ !of_device_is_compatible(of_node,
+ "pasemi,pwrficient-openpic"))
+ return -ENODEV;
+
+ rc = mpic_msi_init_allocator(mpic);
+ if (rc) {
+ pr_debug("pasemi_msi: Error allocating bitmap!\n");
+ return rc;
+ }
+
+ pr_debug("pasemi_msi: Registering PA Semi MPIC MSI callbacks\n");
+
+ msi_mpic = mpic;
+ list_for_each_entry(phb, &hose_list, list_node) {
+ WARN_ON(phb->controller_ops.setup_msi_irqs);
+ phb->controller_ops.setup_msi_irqs = pasemi_msi_setup_msi_irqs;
+ phb->controller_ops.teardown_msi_irqs = pasemi_msi_teardown_msi_irqs;
+ }
+
+ return 0;
+}