2 * Copyright 2011 IBM Corporation.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
10 #include <linux/types.h>
11 #include <linux/kernel.h>
12 #include <linux/irq.h>
13 #include <linux/smp.h>
14 #include <linux/interrupt.h>
15 #include <linux/init.h>
16 #include <linux/cpu.h>
21 #include <asm/errno.h>
24 #include <asm/hvcall.h>
26 static inline unsigned int icp_hv_get_xirr(unsigned char cppr)
28 unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
30 unsigned int ret = XICS_IRQ_SPURIOUS;
32 rc = plpar_hcall(H_XIRR, retbuf, cppr);
33 if (rc == H_SUCCESS) {
34 ret = (unsigned int)retbuf[0];
36 pr_err("%s: bad return code xirr cppr=0x%x returned %ld\n",
44 static inline void icp_hv_set_cppr(u8 value)
46 long rc = plpar_hcall_norets(H_CPPR, value);
47 if (rc != H_SUCCESS) {
48 pr_err("%s: bad return code cppr cppr=0x%x returned %ld\n",
54 static inline void icp_hv_set_xirr(unsigned int value)
56 long rc = plpar_hcall_norets(H_EOI, value);
57 if (rc != H_SUCCESS) {
58 pr_err("%s: bad return code eoi xirr=0x%x returned %ld\n",
61 icp_hv_set_cppr(value >> 24);
65 static inline void icp_hv_set_qirr(int n_cpu , u8 value)
67 int hw_cpu = get_hard_smp_processor_id(n_cpu);
68 long rc = plpar_hcall_norets(H_IPI, hw_cpu, value);
69 if (rc != H_SUCCESS) {
70 pr_err("%s: bad return code qirr cpu=%d hw_cpu=%d mfrr=0x%x "
71 "returned %ld\n", __func__, n_cpu, hw_cpu, value, rc);
76 static void icp_hv_eoi(struct irq_data *d)
78 unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
81 icp_hv_set_xirr((xics_pop_cppr() << 24) | hw_irq);
84 static void icp_hv_teardown_cpu(void)
86 int cpu = smp_processor_id();
88 /* Clear any pending IPI */
89 icp_hv_set_qirr(cpu, 0xff);
92 static void icp_hv_flush_ipi(void)
94 /* We take the ipi irq but and never return so we
95 * need to EOI the IPI, but want to leave our priority 0
97 * should we check all the other interrupts too?
98 * should we be flagging idle loop instead?
99 * or creating some task to be scheduled?
102 icp_hv_set_xirr((0x00 << 24) | XICS_IPI);
105 static unsigned int icp_hv_get_irq(void)
107 unsigned int xirr = icp_hv_get_xirr(xics_cppr_top());
108 unsigned int vec = xirr & 0x00ffffff;
111 if (vec == XICS_IRQ_SPURIOUS)
114 irq = irq_find_mapping(xics_host, vec);
115 if (likely(irq != NO_IRQ)) {
120 /* We don't have a linux mapping, so have rtas mask it. */
121 xics_mask_unknown_vec(vec);
123 /* We might learn about it later, so EOI it */
124 icp_hv_set_xirr(xirr);
129 static void icp_hv_set_cpu_priority(unsigned char cppr)
131 xics_set_base_cppr(cppr);
132 icp_hv_set_cppr(cppr);
138 static void icp_hv_cause_ipi(int cpu, unsigned long data)
140 icp_hv_set_qirr(cpu, IPI_PRIORITY);
143 static irqreturn_t icp_hv_ipi_action(int irq, void *dev_id)
145 int cpu = smp_processor_id();
147 icp_hv_set_qirr(cpu, 0xff);
149 return smp_ipi_demux();
152 #endif /* CONFIG_SMP */
154 static const struct icp_ops icp_hv_ops = {
155 .get_irq = icp_hv_get_irq,
157 .set_priority = icp_hv_set_cpu_priority,
158 .teardown_cpu = icp_hv_teardown_cpu,
159 .flush_ipi = icp_hv_flush_ipi,
161 .ipi_action = icp_hv_ipi_action,
162 .cause_ipi = icp_hv_cause_ipi,
166 int icp_hv_init(void)
168 struct device_node *np;
170 np = of_find_compatible_node(NULL, NULL, "ibm,ppc-xicp");
172 np = of_find_node_by_type(NULL,
173 "PowerPC-External-Interrupt-Presentation");
177 icp_ops = &icp_hv_ops;