2 * Copyright 2016 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.
9 #include <linux/types.h>
10 #include <linux/kernel.h>
11 #include <linux/irq.h>
12 #include <linux/smp.h>
13 #include <linux/interrupt.h>
14 #include <linux/cpu.h>
19 #include <asm/errno.h>
24 static void icp_opal_teardown_cpu(void)
26 int hw_cpu
= hard_smp_processor_id();
28 /* Clear any pending IPI */
29 opal_int_set_mfrr(hw_cpu
, 0xff);
32 static void icp_opal_flush_ipi(void)
35 * We take the ipi irq but and never return so we need to EOI the IPI,
36 * but want to leave our priority 0.
38 * Should we check all the other interrupts too?
39 * Should we be flagging idle loop instead?
40 * Or creating some task to be scheduled?
42 opal_int_eoi((0x00 << 24) | XICS_IPI
);
45 static unsigned int icp_opal_get_irq(void)
52 rc
= opal_int_get_xirr(&xirr
, false);
55 xirr
= be32_to_cpu(xirr
);
56 vec
= xirr
& 0x00ffffff;
57 if (vec
== XICS_IRQ_SPURIOUS
)
60 irq
= irq_find_mapping(xics_host
, vec
);
61 if (likely(irq
!= NO_IRQ
)) {
66 /* We don't have a linux mapping, so have rtas mask it. */
67 xics_mask_unknown_vec(vec
);
69 /* We might learn about it later, so EOI it */
75 static void icp_opal_set_cpu_priority(unsigned char cppr
)
77 xics_set_base_cppr(cppr
);
78 opal_int_set_cppr(cppr
);
82 static void icp_opal_eoi(struct irq_data
*d
)
84 unsigned int hw_irq
= (unsigned int)irqd_to_hwirq(d
);
88 rc
= opal_int_eoi((xics_pop_cppr() << 24) | hw_irq
);
91 * EOI tells us whether there are more interrupts to fetch.
93 * Some HW implementations might not be able to send us another
94 * external interrupt in that case, so we force a replay.
97 force_external_irq_replay();
102 static void icp_opal_cause_ipi(int cpu
, unsigned long data
)
104 int hw_cpu
= get_hard_smp_processor_id(cpu
);
106 opal_int_set_mfrr(hw_cpu
, IPI_PRIORITY
);
109 static irqreturn_t
icp_opal_ipi_action(int irq
, void *dev_id
)
111 int hw_cpu
= hard_smp_processor_id();
113 opal_int_set_mfrr(hw_cpu
, 0xff);
115 return smp_ipi_demux();
118 #endif /* CONFIG_SMP */
120 static const struct icp_ops icp_opal_ops
= {
121 .get_irq
= icp_opal_get_irq
,
123 .set_priority
= icp_opal_set_cpu_priority
,
124 .teardown_cpu
= icp_opal_teardown_cpu
,
125 .flush_ipi
= icp_opal_flush_ipi
,
127 .ipi_action
= icp_opal_ipi_action
,
128 .cause_ipi
= icp_opal_cause_ipi
,
132 int icp_opal_init(void)
134 struct device_node
*np
;
136 np
= of_find_compatible_node(NULL
, NULL
, "ibm,opal-intc");
140 icp_ops
= &icp_opal_ops
;
142 printk("XICS: Using OPAL ICP fallbacks\n");