MIPS: Netlogic: Add basic MSI support for XLR/XLS

Add basic support for MSI.

Signed-off-by: Ganesan Ramalingam <ganesanr@netlogicmicro.com>
Signed-off-by: Jayachandran C <jayachandranc@netlogicmicro.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2730/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 50 insertions, 1 deletions

diff --git a/arch/mips/pci/pci-xlr.c b/arch/mips/pci/pci-xlr.c
index 38fece16c435..87404d0034d2 100644
--- a/arch/mips/pci/pci-xlr.c
+++ b/arch/mips/pci/pci-xlr.c
@@ -36,12 +36,16 @@
 #include <linux/pci.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
+#include <linux/msi.h>
 #include <linux/mm.h>
+#include <linux/irq.h>
+#include <linux/irqdesc.h>
 #include <linux/console.h>
 
 #include <asm/io.h>
 
 #include <asm/netlogic/interrupt.h>
+#include <asm/netlogic/xlr/msidef.h>
 #include <asm/netlogic/xlr/iomap.h>
 #include <asm/netlogic/xlr/pic.h>
 #include <asm/netlogic/xlr/xlr.h>
@@ -150,7 +154,7 @@ struct pci_controller nlm_pci_controller = {
         .io_offset      = 0x00000000UL,
 };
 
-int __init pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+static int get_irq_vector(const struct pci_dev *dev)
 {
         if (!nlm_chip_is_xls())
                 return  PIC_PCIX_IRQ;   /* for XLR just one IRQ*/
@@ -182,6 +186,51 @@ int __init pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
         return 0;
 }
 
+#ifdef CONFIG_PCI_MSI
+void destroy_irq(unsigned int irq)
+{
+            /* nothing to do yet */
+}
+
+void arch_teardown_msi_irq(unsigned int irq)
+{
+        destroy_irq(irq);
+}
+
+int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
+{
+        struct msi_msg msg;
+        int irq, ret;
+
+        irq = get_irq_vector(dev);
+        if (irq <= 0)
+                return 1;
+
+        msg.address_hi = MSI_ADDR_BASE_HI;
+        msg.address_lo = MSI_ADDR_BASE_LO   |
+                MSI_ADDR_DEST_MODE_PHYSICAL |
+                MSI_ADDR_REDIRECTION_CPU;
+
+        msg.data = MSI_DATA_TRIGGER_EDGE |
+                MSI_DATA_LEVEL_ASSERT    |
+                MSI_DATA_DELIVERY_FIXED;
+
+        ret = irq_set_msi_desc(irq, desc);
+        if (ret < 0) {
+                destroy_irq(irq);
+                return ret;
+        }
+
+        write_msi_msg(irq, &msg);
+        return 0;
+}
+#endif
+
+int __init pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+        return get_irq_vector(dev);
+}
+
 /* Do platform specific device initialization at pci_enable_device() time */
 int pcibios_plat_dev_init(struct pci_dev *dev)
 {