powerpc/fsl_msi: fix the conflict of virt_msir's chip_data

In fsl_of_msi_probe(), the virt_msir's chip_data have been stored
the pointer to struct mpic. We add a struct fsl_msi_cascade_data
to store the pointer to struct fsl_msi and msir_index in hanler_data.
Otherwise, the pointer to struct mpic will be over-written, and will
cause problem when calling eoi() of the irq.
Signed-off-by: Zhao Chenhui <b26998@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

arch/powerpc/sysdev/fsl_msi.c

@@ -22,6 +22,7 @@
 #include <asm/prom.h>
 #include <asm/hw_irq.h>
 #include <asm/ppc-pci.h>
+#include <asm/mpic.h>
 #include "fsl_msi.h"
 
 struct fsl_msi_feature {
@@ -29,6 +30,10 @@ struct fsl_msi_feature {
 	u32 msiir_offset;
 };
 
+struct fsl_msi_cascade_data {
+	struct fsl_msi *msi_data;
+	int index;
+};
 
 static inline u32 fsl_msi_read(u32 __iomem *base, unsigned int reg)
 {
@@ -102,7 +107,7 @@ static void fsl_teardown_msi_irqs(struct pci_dev *pdev)
 	list_for_each_entry(entry, &pdev->msi_list, list) {
 		if (entry->irq == NO_IRQ)
 			continue;
-		msi_data = get_irq_chip_data(entry->irq);
+		msi_data = get_irq_data(entry->irq);
 		set_irq_msi(entry->irq, NULL);
 		msi_bitmap_free_hwirqs(&msi_data->bitmap,
 				       virq_to_hw(entry->irq), 1);
@@ -133,7 +138,7 @@ static void fsl_compose_msi_msg(struct pci_dev *pdev, int hwirq,
 
 static int fsl_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
 {
-	int rc, hwirq;
+	int rc, hwirq = NO_IRQ;
 	unsigned int virq;
 	struct msi_desc *entry;
 	struct msi_msg msg;
@@ -159,6 +164,7 @@ static int fsl_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
 			rc = -ENOSPC;
 			goto out_free;
 		}
+		set_irq_data(virq, msi_data);
 		set_irq_msi(virq, entry);
 
 		fsl_compose_msi_msg(pdev, hwirq, &msg, msi_data);
@@ -173,11 +179,15 @@ static int fsl_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
 static void fsl_msi_cascade(unsigned int irq, struct irq_desc *desc)
 {
 	unsigned int cascade_irq;
-	struct fsl_msi *msi_data = get_irq_chip_data(irq);
+	struct fsl_msi *msi_data;
 	int msir_index = -1;
 	u32 msir_value = 0;
 	u32 intr_index;
 	u32 have_shift = 0;
+	struct fsl_msi_cascade_data *cascade_data;
+
+	cascade_data = (struct fsl_msi_cascade_data *)get_irq_data(irq);
+	msi_data = cascade_data->msi_data;
 
 	raw_spin_lock(&desc->lock);
 	if ((msi_data->feature &  FSL_PIC_IP_MASK) == FSL_PIC_IP_IPIC) {
@@ -192,7 +202,7 @@ static void fsl_msi_cascade(unsigned int irq, struct irq_desc *desc)
 	if (unlikely(desc->status & IRQ_INPROGRESS))
 		goto unlock;
 
-	msir_index = (int)desc->handler_data;
+	msir_index = cascade_data->index;
 
 	if (msir_index >= NR_MSI_REG)
 		cascade_irq = NO_IRQ;
@@ -244,6 +254,7 @@ static int __devinit fsl_of_msi_probe(struct of_device *dev,
 	int virt_msir;
 	const u32 *p;
 	struct fsl_msi_feature *features = match->data;
+	struct fsl_msi_cascade_data *cascade_data = NULL;
 
 	printk(KERN_DEBUG "Setting up Freescale MSI support\n");
 
@@ -310,9 +321,19 @@ static int __devinit fsl_of_msi_probe(struct of_device *dev,
 			break;
 		virt_msir = irq_of_parse_and_map(dev->node, i);
 		if (virt_msir != NO_IRQ) {
-			set_irq_data(virt_msir, (void *)i);
+			cascade_data = kzalloc(
+					sizeof(struct fsl_msi_cascade_data),
+					GFP_KERNEL);
+			if (!cascade_data) {
+				dev_err(&dev->dev,
+					"No memory for MSI cascade data\n");
+				err = -ENOMEM;
+				goto error_out;
+			}
+			cascade_data->index = i;
+			cascade_data->msi_data = msi;
+			set_irq_data(virt_msir, (void *)cascade_data);
 			set_irq_chained_handler(virt_msir, fsl_msi_cascade);
-			set_irq_chip_data(virt_msir, msi);
 		}
 	}