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authorGrant Likely <grant.likely@secretlab.ca>2007-10-02 12:15:23 +1000
committerJosh Boyer <jwboyer@linux.vnet.ibm.com>2007-10-03 07:23:14 -0500
commit4dc9783ea9e4d6f97e40b808991b324a4719a837 (patch)
treefa1bf0ba7f841455934306315f6549a98dd267d7 /arch/powerpc/sysdev/xilinx_intc.c
parent36660cef734e3c80c4379443781ed0b2fe3e1ffe (diff)
[POWERPC] Virtex: add xilinx interrupt controller driver
Adds support for the Xilinx opb-intc interrupt controller Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Diffstat (limited to 'arch/powerpc/sysdev/xilinx_intc.c')
-rw-r--r--arch/powerpc/sysdev/xilinx_intc.c151
1 files changed, 151 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/xilinx_intc.c b/arch/powerpc/sysdev/xilinx_intc.c
new file mode 100644
index 00000000000..c2f17cc43df
--- /dev/null
+++ b/arch/powerpc/sysdev/xilinx_intc.c
@@ -0,0 +1,151 @@
+/*
+ * Interrupt controller driver for Xilinx Virtex FPGAs
+ *
+ * Copyright (C) 2007 Secret Lab Technologies Ltd.
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ *
+ */
+
+/*
+ * This is a driver for the interrupt controller typically found in
+ * Xilinx Virtex FPGA designs.
+ *
+ * The interrupt sense levels are hard coded into the FPGA design with
+ * typically a 1:1 relationship between irq lines and devices (no shared
+ * irq lines). Therefore, this driver does not attempt to handle edge
+ * and level interrupts differently.
+ */
+#undef DEBUG
+
+#include <linux/kernel.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/irq.h>
+
+/*
+ * INTC Registers
+ */
+#define XINTC_ISR 0 /* Interrupt Status */
+#define XINTC_IPR 4 /* Interrupt Pending */
+#define XINTC_IER 8 /* Interrupt Enable */
+#define XINTC_IAR 12 /* Interrupt Acknowledge */
+#define XINTC_SIE 16 /* Set Interrupt Enable bits */
+#define XINTC_CIE 20 /* Clear Interrupt Enable bits */
+#define XINTC_IVR 24 /* Interrupt Vector */
+#define XINTC_MER 28 /* Master Enable */
+
+static struct irq_host *master_irqhost;
+
+/*
+ * IRQ Chip operations
+ */
+static void xilinx_intc_mask(unsigned int virq)
+{
+ int irq = virq_to_hw(virq);
+ void * regs = get_irq_chip_data(virq);
+ pr_debug("mask: %d\n", irq);
+ out_be32(regs + XINTC_CIE, 1 << irq);
+}
+
+static void xilinx_intc_unmask(unsigned int virq)
+{
+ int irq = virq_to_hw(virq);
+ void * regs = get_irq_chip_data(virq);
+ pr_debug("unmask: %d\n", irq);
+ out_be32(regs + XINTC_SIE, 1 << irq);
+}
+
+static void xilinx_intc_ack(unsigned int virq)
+{
+ int irq = virq_to_hw(virq);
+ void * regs = get_irq_chip_data(virq);
+ pr_debug("ack: %d\n", irq);
+ out_be32(regs + XINTC_IAR, 1 << irq);
+}
+
+static struct irq_chip xilinx_intc_irqchip = {
+ .typename = "Xilinx INTC",
+ .mask = xilinx_intc_mask,
+ .unmask = xilinx_intc_unmask,
+ .ack = xilinx_intc_ack,
+};
+
+/*
+ * IRQ Host operations
+ */
+static int xilinx_intc_map(struct irq_host *h, unsigned int virq,
+ irq_hw_number_t irq)
+{
+ set_irq_chip_data(virq, h->host_data);
+ set_irq_chip_and_handler(virq, &xilinx_intc_irqchip, handle_level_irq);
+ set_irq_type(virq, IRQ_TYPE_NONE);
+ return 0;
+}
+
+static struct irq_host_ops xilinx_intc_ops = {
+ .map = xilinx_intc_map,
+};
+
+struct irq_host * __init
+xilinx_intc_init(struct device_node *np)
+{
+ struct irq_host * irq;
+ struct resource res;
+ void * regs;
+ int rc;
+
+ /* Find and map the intc registers */
+ rc = of_address_to_resource(np, 0, &res);
+ if (rc) {
+ printk(KERN_ERR __FILE__ ": of_address_to_resource() failed\n");
+ return NULL;
+ }
+ regs = ioremap(res.start, 32);
+
+ printk(KERN_INFO "Xilinx intc at 0x%08X mapped to 0x%p\n",
+ res.start, regs);
+
+ /* Setup interrupt controller */
+ out_be32(regs + XINTC_IER, 0); /* disable all irqs */
+ out_be32(regs + XINTC_IAR, ~(u32) 0); /* Acknowledge pending irqs */
+ out_be32(regs + XINTC_MER, 0x3UL); /* Turn on the Master Enable. */
+
+ /* Allocate and initialize an irq_host structure. */
+ irq = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, 32, &xilinx_intc_ops, -1);
+ if (!irq)
+ panic(__FILE__ ": Cannot allocate IRQ host\n");
+ irq->host_data = regs;
+ return irq;
+}
+
+int xilinx_intc_get_irq(void)
+{
+ void * regs = master_irqhost->host_data;
+ pr_debug("get_irq:\n");
+ return irq_linear_revmap(master_irqhost, in_be32(regs + XINTC_IVR));
+}
+
+void __init xilinx_intc_init_tree(void)
+{
+ struct device_node *np;
+
+ /* find top level interrupt controller */
+ for_each_compatible_node(np, NULL, "xilinx,intc") {
+ if (!of_get_property(np, "interrupts", NULL))
+ break;
+ }
+
+ /* xilinx interrupt controller needs to be top level */
+ BUG_ON(!np);
+
+ master_irqhost = xilinx_intc_init(np);
+ BUG_ON(!master_irqhost);
+
+ irq_set_default_host(master_irqhost);
+ of_node_put(np);
+}