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, id);
96	raw_spin_unlock_irqrestore(&intc_big_lock, flags);
97}
98