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authorPaul Mundt <lethal@linux-sh.org>2011-05-23 23:05:26 -0400
committerPaul Mundt <lethal@linux-sh.org>2011-05-23 23:05:26 -0400
commit8b1aaeaf54f1bcaa0bbec6bb170db367c998d27c (patch)
tree2478e1708f5a3da261597f4aa1011d4d41c2cc84 /arch/powerpc/sysdev/xics/icp-hv.c
parentbca606a646a2b1f4fa1ae2b22a0ac707505d7297 (diff)
parent5e152b4c9e0fce6149c74406346a7ae7e7a17727 (diff)
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into rmobile-latest
Diffstat (limited to 'arch/powerpc/sysdev/xics/icp-hv.c')
-rw-r--r--arch/powerpc/sysdev/xics/icp-hv.c164
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 @@
1/*
2 * Copyright 2011 IBM Corporation.
3 *
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.
8 *
9 */
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>
17#include <linux/of.h>
18
19#include <asm/smp.h>
20#include <asm/irq.h>
21#include <asm/errno.h>
22#include <asm/xics.h>
23#include <asm/io.h>
24#include <asm/hvcall.h>
25
26static inline unsigned int icp_hv_get_xirr(unsigned char cppr)
27{
28 unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
29 long rc;
30
31 rc = plpar_hcall(H_XIRR, retbuf, cppr);
32 if (rc != H_SUCCESS)
33 panic(" bad return code xirr - rc = %lx\n", rc);
34 return (unsigned int)retbuf[0];
35}
36
37static inline void icp_hv_set_xirr(unsigned int value)
38{
39 long rc = plpar_hcall_norets(H_EOI, value);
40 if (rc != H_SUCCESS)
41 panic("bad return code EOI - rc = %ld, value=%x\n", rc, value);
42}
43
44static inline void icp_hv_set_cppr(u8 value)
45{
46 long rc = plpar_hcall_norets(H_CPPR, value);
47 if (rc != H_SUCCESS)
48 panic("bad return code cppr - rc = %lx\n", rc);
49}
50
51static inline void icp_hv_set_qirr(int n_cpu , u8 value)
52{
53 long rc = plpar_hcall_norets(H_IPI, get_hard_smp_processor_id(n_cpu),
54 value);
55 if (rc != H_SUCCESS)
56 panic("bad return code qirr - rc = %lx\n", rc);
57}
58
59static void icp_hv_eoi(struct irq_data *d)
60{
61 unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
62
63 iosync();
64 icp_hv_set_xirr((xics_pop_cppr() << 24) | hw_irq);
65}
66
67static void icp_hv_teardown_cpu(void)
68{
69 int cpu = smp_processor_id();
70
71 /* Clear any pending IPI */
72 icp_hv_set_qirr(cpu, 0xff);
73}
74
75static void icp_hv_flush_ipi(void)
76{
77 /* We take the ipi irq but and never return so we
78 * need to EOI the IPI, but want to leave our priority 0
79 *
80 * should we check all the other interrupts too?
81 * should we be flagging idle loop instead?
82 * or creating some task to be scheduled?
83 */
84
85 icp_hv_set_xirr((0x00 << 24) | XICS_IPI);
86}
87
88static unsigned int icp_hv_get_irq(void)
89{
90 unsigned int xirr = icp_hv_get_xirr(xics_cppr_top());
91 unsigned int vec = xirr & 0x00ffffff;
92 unsigned int irq;
93
94 if (vec == XICS_IRQ_SPURIOUS)
95 return NO_IRQ;
96
97 irq = irq_radix_revmap_lookup(xics_host, vec);
98 if (likely(irq != NO_IRQ)) {
99 xics_push_cppr(vec);
100 return irq;
101 }
102
103 /* We don't have a linux mapping, so have rtas mask it. */
104 xics_mask_unknown_vec(vec);
105
106 /* We might learn about it later, so EOI it */
107 icp_hv_set_xirr(xirr);
108
109 return NO_IRQ;
110}
111
112static void icp_hv_set_cpu_priority(unsigned char cppr)
113{
114 xics_set_base_cppr(cppr);
115 icp_hv_set_cppr(cppr);
116 iosync();
117}
118
119#ifdef CONFIG_SMP
120
121static void icp_hv_cause_ipi(int cpu, unsigned long data)
122{
123 icp_hv_set_qirr(cpu, IPI_PRIORITY);
124}
125
126static irqreturn_t icp_hv_ipi_action(int irq, void *dev_id)
127{
128 int cpu = smp_processor_id();
129
130 icp_hv_set_qirr(cpu, 0xff);
131
132 return smp_ipi_demux();
133}
134
135#endif /* CONFIG_SMP */
136
137static const struct icp_ops icp_hv_ops = {
138 .get_irq = icp_hv_get_irq,
139 .eoi = icp_hv_eoi,
140 .set_priority = icp_hv_set_cpu_priority,
141 .teardown_cpu = icp_hv_teardown_cpu,
142 .flush_ipi = icp_hv_flush_ipi,
143#ifdef CONFIG_SMP
144 .ipi_action = icp_hv_ipi_action,
145 .cause_ipi = icp_hv_cause_ipi,
146#endif
147};
148
149int icp_hv_init(void)
150{
151 struct device_node *np;
152
153 np = of_find_compatible_node(NULL, NULL, "ibm,ppc-xicp");
154 if (!np)
155 np = of_find_node_by_type(NULL,
156 "PowerPC-External-Interrupt-Presentation");
157 if (!np)
158 return -ENODEV;
159
160 icp_ops = &icp_hv_ops;
161
162 return 0;
163}
164