powerpc/wsp: Add MSI support for PCI on PowerEN

Based on a patch by Michael Ellerman <michael@ellerman.id.au>

Patch was simply forward ported upstream.

Jimi Xenidis <jimix@pobox.com>

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 102 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/wsp/msi.c b/arch/powerpc/platforms/wsp/msi.c
new file mode 100644
index 000000000000..380882f27add
--- /dev/null
+++ b/arch/powerpc/platforms/wsp/msi.c
@@ -0,0 +1,102 @@
+/*
+ * Copyright 2011 Michael Ellerman, IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/msi.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+
+#include "msi.h"
+#include "ics.h"
+#include "wsp_pci.h"
+
+/* Magic addresses for 32 & 64-bit MSIs with hardcoded MVE 0 */
+#define MSI_ADDR_32             0xFFFF0000ul
+#define MSI_ADDR_64             0x1000000000000000ul
+
+int wsp_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+        struct pci_controller *phb;
+        struct msi_desc *entry;
+        struct msi_msg msg;
+        unsigned int virq;
+        int hwirq;
+
+        phb = pci_bus_to_host(dev->bus);
+        if (!phb)
+                return -ENOENT;
+
+        entry = list_first_entry(&dev->msi_list, struct msi_desc, list);
+        if (entry->msi_attrib.is_64) {
+                msg.address_lo = 0;
+                msg.address_hi = MSI_ADDR_64 >> 32;
+        } else {
+                msg.address_lo = MSI_ADDR_32;
+                msg.address_hi = 0;
+        }
+
+        list_for_each_entry(entry, &dev->msi_list, list) {
+                hwirq = wsp_ics_alloc_irq(phb->dn, 1);
+                if (hwirq < 0) {
+                        dev_warn(&dev->dev, "wsp_msi: hwirq alloc failed!\n");
+                        return hwirq;
+                }
+
+                virq = irq_create_mapping(NULL, hwirq);
+                if (virq == NO_IRQ) {
+                        dev_warn(&dev->dev, "wsp_msi: virq alloc failed!\n");
+                        return -1;
+                }
+
+                dev_dbg(&dev->dev, "wsp_msi: allocated irq %#x/%#x\n",
+                        hwirq, virq);
+
+                wsp_ics_set_msi_chip(virq);
+                irq_set_msi_desc(virq, entry);
+                msg.data = hwirq & XIVE_ADDR_MASK;
+                write_msi_msg(virq, &msg);
+        }
+
+        return 0;
+}
+
+void wsp_teardown_msi_irqs(struct pci_dev *dev)
+{
+        struct pci_controller *phb;
+        struct msi_desc *entry;
+        int hwirq;
+
+        phb = pci_bus_to_host(dev->bus);
+
+        dev_dbg(&dev->dev, "wsp_msi: tearing down msi irqs\n");
+
+        list_for_each_entry(entry, &dev->msi_list, list) {
+                if (entry->irq == NO_IRQ)
+                        continue;
+
+                irq_set_msi_desc(entry->irq, NULL);
+                wsp_ics_set_std_chip(entry->irq);
+
+                hwirq = virq_to_hw(entry->irq);
+                /* In this order to avoid racing with irq_create_mapping() */
+                irq_dispose_mapping(entry->irq);
+                wsp_ics_free_irq(phb->dn, hwirq);
+        }
+}
+
+void wsp_setup_phb_msi(struct pci_controller *phb)
+{
+        /* Create a single MVE at offset 0 that matches everything */
+        out_be64(phb->cfg_data + PCIE_REG_IODA_ADDR, PCIE_REG_IODA_AD_TBL_MVT);
+        out_be64(phb->cfg_data + PCIE_REG_IODA_DATA0, 1ull << 63);
+
+        ppc_md.setup_msi_irqs = wsp_setup_msi_irqs;
+        ppc_md.teardown_msi_irqs = wsp_teardown_msi_irqs;
+}