1/*
2 * Support for hardware-managed IRQ auto-distribution.
3 *
4 * Copyright (C) 2010 Paul Mundt
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10#include "internals.h"
11
12static unsigned long dist_handle[INTC_NR_IRQS];
13
14void intc_balancing_enable(unsigned int irq)
15{
16 struct intc_desc_int *d = get_intc_desc(irq);
17 unsigned long handle = dist_handle[irq];
18 unsigned long addr;
19
20 if (irq_balancing_disabled(irq) || !handle)
21 return;
22
23 addr = INTC_REG(d, _INTC_ADDR_D(handle), 0);
24 intc_reg_fns[_INTC_FN(handle)](addr, handle, 1);
25}
26
27void intc_balancing_disable(unsigned int irq)
28{
29 struct intc_desc_int *d = get_intc_desc(irq);
30 unsigned long handle = dist_handle[irq];
31 unsigned long addr;
32
33 if (irq_balancing_disabled(irq) || !handle)
34 return;
35
36 addr = INTC_REG(d, _INTC_ADDR_D(handle), 0);
37 intc_reg_fns[_INTC_FN(handle)](addr, handle, 0);
38}
39
40static unsigned int intc_dist_data(struct intc_desc *desc,
41 struct intc_desc_int *d,
42 intc_enum enum_id)
43{
44 struct intc_mask_reg *mr = desc->hw.mask_regs;
45 unsigned int i, j, fn, mode;
46 unsigned long reg_e, reg_d;
47
48 for (i = 0; mr && enum_id && i < desc->hw.nr_mask_regs; i++) {
49 mr = desc->hw.mask_regs + i;
50
51 /*
52 * Skip this entry if there's no auto-distribution
53 * register associated with it.
54 */
55 if (!mr->dist_reg)
56 continue;
57
58 for (j = 0; j < ARRAY_SIZE(mr->enum_ids); j++) {
59 if (mr->enum_ids[j] != enum_id)
60 continue;
61
62 fn = REG_FN_MODIFY_BASE;
63 mode = MODE_ENABLE_REG;
64 reg_e = mr->dist_reg;
65 reg_d = mr->dist_reg;
66
67 fn += (mr->reg_width >> 3) - 1;
68 return _INTC_MK(fn, mode,
69 intc_get_reg(d, reg_e),
70 intc_get_reg(d, reg_d),
71 1,
72 (mr->reg_width - 1) - j);
73 }
74 }
75
76 /*
77 * It's possible we've gotten here with no distribution options
78 * available for the IRQ in question, so we just skip over those.
79 */
80 return 0;
81}
82
83void intc_set_dist_handle(unsigned int irq, struct intc_desc *desc,
84 struct intc_desc_int *d, intc_enum id)
85{
86 unsigned long flags;
87
88 /*
89 * Nothing to do for this IRQ.
90 */
91 if (!desc->hw.mask_regs)
92 return;
93
94 raw_spin_lock_irqsave(&intc_big_lock, flags);
95 dist_handle[irq] = intc_dist_data(desc, d, enum_id: id);
96 raw_spin_unlock_irqrestore(&intc_big_lock, flags);
97}
98

source code of linux/drivers/sh/intc/balancing.c