1 files changed, 164 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/xics/icp-hv.c b/arch/powerpc/sysdev/xics/icp-hv.c
new file mode 100644
index 000000000000..9518d367a64f
--- /dev/null
+++ b/arch/powerpc/sysdev/xics/icp-hv.c
@@ -0,0 +1,164 @@
+/*
+ * Copyright 2011 IBM Corporation.
+ *
+ *  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/types.h>
+#include <linux/kernel.h>
+#include <linux/irq.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/of.h>
+
+#include <asm/smp.h>
+#include <asm/irq.h>
+#include <asm/errno.h>
+#include <asm/xics.h>
+#include <asm/io.h>
+#include <asm/hvcall.h>
+
+static inline unsigned int icp_hv_get_xirr(unsigned char cppr)
+{
+	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
+	long rc;
+
+	rc = plpar_hcall(H_XIRR, retbuf, cppr);
+	if (rc != H_SUCCESS)
+		panic(" bad return code xirr - rc = %lx\n", rc);
+	return (unsigned int)retbuf[0];
+}
+
+static inline void icp_hv_set_xirr(unsigned int value)
+{
+	long rc = plpar_hcall_norets(H_EOI, value);
+	if (rc != H_SUCCESS)
+		panic("bad return code EOI - rc = %ld, value=%x\n", rc, value);
+}
+
+static inline void icp_hv_set_cppr(u8 value)
+{
+	long rc = plpar_hcall_norets(H_CPPR, value);
+	if (rc != H_SUCCESS)
+		panic("bad return code cppr - rc = %lx\n", rc);
+}
+
+static inline void icp_hv_set_qirr(int n_cpu , u8 value)
+{
+	long rc = plpar_hcall_norets(H_IPI, get_hard_smp_processor_id(n_cpu),
+				     value);
+	if (rc != H_SUCCESS)
+		panic("bad return code qirr - rc = %lx\n", rc);
+}
+
+static void icp_hv_eoi(struct irq_data *d)
+{
+	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
+
+	iosync();
+	icp_hv_set_xirr((xics_pop_cppr() << 24) | hw_irq);
+}
+
+static void icp_hv_teardown_cpu(void)
+{
+	int cpu = smp_processor_id();
+
+	/* Clear any pending IPI */
+	icp_hv_set_qirr(cpu, 0xff);
+}
+
+static void icp_hv_flush_ipi(void)
+{
+	/* We take the ipi irq but and never return so we
+	 * need to EOI the IPI, but want to leave our priority 0
+	 *
+	 * should we check all the other interrupts too?
+	 * should we be flagging idle loop instead?
+	 * or creating some task to be scheduled?
+	 */
+
+	icp_hv_set_xirr((0x00 << 24) | XICS_IPI);
+}
+
+static unsigned int icp_hv_get_irq(void)
+{
+	unsigned int xirr = icp_hv_get_xirr(xics_cppr_top());
+	unsigned int vec = xirr & 0x00ffffff;
+	unsigned int irq;
+
+	if (vec == XICS_IRQ_SPURIOUS)
+		return NO_IRQ;
+
+	irq = irq_radix_revmap_lookup(xics_host, vec);
+	if (likely(irq != NO_IRQ)) {
+		xics_push_cppr(vec);
+		return irq;
+	}
+
+	/* We don't have a linux mapping, so have rtas mask it. */
+	xics_mask_unknown_vec(vec);
+
+	/* We might learn about it later, so EOI it */
+	icp_hv_set_xirr(xirr);
+
+	return NO_IRQ;
+}
+
+static void icp_hv_set_cpu_priority(unsigned char cppr)
+{
+	xics_set_base_cppr(cppr);
+	icp_hv_set_cppr(cppr);
+	iosync();
+}
+
+#ifdef CONFIG_SMP
+
+static void icp_hv_cause_ipi(int cpu, unsigned long data)
+{
+	icp_hv_set_qirr(cpu, IPI_PRIORITY);
+}
+
+static irqreturn_t icp_hv_ipi_action(int irq, void *dev_id)
+{
+	int cpu = smp_processor_id();
+
+	icp_hv_set_qirr(cpu, 0xff);
+
+	return smp_ipi_demux();
+}
+
+#endif /* CONFIG_SMP */
+
+static const struct icp_ops icp_hv_ops = {
+	.get_irq	= icp_hv_get_irq,
+	.eoi		= icp_hv_eoi,
+	.set_priority	= icp_hv_set_cpu_priority,
+	.teardown_cpu	= icp_hv_teardown_cpu,
+	.flush_ipi	= icp_hv_flush_ipi,
+#ifdef CONFIG_SMP
+	.ipi_action	= icp_hv_ipi_action,
+	.cause_ipi	= icp_hv_cause_ipi,
+#endif
+};
+
+int icp_hv_init(void)
+{
+	struct device_node *np;
+
+	np = of_find_compatible_node(NULL, NULL, "ibm,ppc-xicp");
+	if (!np)
+		np = of_find_node_by_type(NULL,
+				    "PowerPC-External-Interrupt-Presentation");
+	if (!np)
+		return -ENODEV;
+
+	icp_ops = &icp_hv_ops;
+
+	return 0;
+}
+