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-rw-r--r--arch/powerpc/sysdev/mpic_msi.c98
1 files changed, 98 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/mpic_msi.c b/arch/powerpc/sysdev/mpic_msi.c
new file mode 100644
index 000000000..4695c0432
--- /dev/null
+++ b/arch/powerpc/sysdev/mpic_msi.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2006-2007, Michael Ellerman, IBM Corporation.
+ */
+
+#include <linux/irq.h>
+#include <linux/bitmap.h>
+#include <linux/msi.h>
+#include <asm/mpic.h>
+#include <asm/prom.h>
+#include <asm/hw_irq.h>
+#include <asm/ppc-pci.h>
+#include <asm/msi_bitmap.h>
+
+#include <sysdev/mpic.h>
+
+void mpic_msi_reserve_hwirq(struct mpic *mpic, irq_hw_number_t hwirq)
+{
+ /* The mpic calls this even when there is no allocator setup */
+ if (!mpic->msi_bitmap.bitmap)
+ return;
+
+ msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, hwirq);
+}
+
+#ifdef CONFIG_MPIC_U3_HT_IRQS
+static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
+{
+ irq_hw_number_t hwirq;
+ const struct irq_domain_ops *ops = mpic->irqhost->ops;
+ struct device_node *np;
+ int flags, index, i;
+ struct of_phandle_args oirq;
+
+ pr_debug("mpic: found U3, guessing msi allocator setup\n");
+
+ /* Reserve source numbers we know are reserved in the HW.
+ *
+ * This is a bit of a mix of U3 and U4 reserves but that's going
+ * to work fine, we have plenty enugh numbers left so let's just
+ * mark anything we don't like reserved.
+ */
+ for (i = 0; i < 8; i++)
+ msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
+
+ for (i = 42; i < 46; i++)
+ msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
+
+ for (i = 100; i < 105; i++)
+ msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
+
+ for (i = 124; i < mpic->num_sources; i++)
+ msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
+
+
+ np = NULL;
+ while ((np = of_find_all_nodes(np))) {
+ pr_debug("mpic: mapping hwirqs for %pOF\n", np);
+
+ index = 0;
+ while (of_irq_parse_one(np, index++, &oirq) == 0) {
+ ops->xlate(mpic->irqhost, NULL, oirq.args,
+ oirq.args_count, &hwirq, &flags);
+ msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, hwirq);
+ }
+ }
+
+ return 0;
+}
+#else
+static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
+{
+ return -1;
+}
+#endif
+
+int mpic_msi_init_allocator(struct mpic *mpic)
+{
+ int rc;
+
+ rc = msi_bitmap_alloc(&mpic->msi_bitmap, mpic->num_sources,
+ irq_domain_get_of_node(mpic->irqhost));
+ if (rc)
+ return rc;
+
+ rc = msi_bitmap_reserve_dt_hwirqs(&mpic->msi_bitmap);
+ if (rc > 0) {
+ if (mpic->flags & MPIC_U3_HT_IRQS)
+ rc = mpic_msi_reserve_u3_hwirqs(mpic);
+
+ if (rc) {
+ msi_bitmap_free(&mpic->msi_bitmap);
+ return rc;
+ }
+ }
+
+ return 0;
+}