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Diffstat (limited to 'arch/m68k/mac/psc.c')
-rw-r--r--arch/m68k/mac/psc.c197
1 files changed, 197 insertions, 0 deletions
diff --git a/arch/m68k/mac/psc.c b/arch/m68k/mac/psc.c
new file mode 100644
index 000000000000..e72384e43a1e
--- /dev/null
+++ b/arch/m68k/mac/psc.c
@@ -0,0 +1,197 @@
1/*
2 * Apple Peripheral System Controller (PSC)
3 *
4 * The PSC is used on the AV Macs to control IO functions not handled
5 * by the VIAs (Ethernet, DSP, SCC).
6 *
7 * TO DO:
8 *
9 * Try to figure out what's going on in pIFR5 and pIFR6. There seem to be
10 * persisant interrupt conditions in those registers and I have no idea what
11 * they are. Granted it doesn't affect since we're not enabling any interrupts
12 * on those levels at the moment, but it would be nice to know. I have a feeling
13 * they aren't actually interrupt lines but data lines (to the DSP?)
14 */
15
16#include <linux/types.h>
17#include <linux/kernel.h>
18#include <linux/mm.h>
19#include <linux/delay.h>
20#include <linux/init.h>
21
22#include <asm/traps.h>
23#include <asm/bootinfo.h>
24#include <asm/macintosh.h>
25#include <asm/macints.h>
26#include <asm/mac_psc.h>
27
28#define DEBUG_PSC
29
30int psc_present;
31volatile __u8 *psc;
32
33irqreturn_t psc_irq(int, void *, struct pt_regs *);
34
35/*
36 * Debugging dump, used in various places to see what's going on.
37 */
38
39void psc_debug_dump(void)
40{
41 int i;
42
43 if (!psc_present) return;
44 for (i = 0x30 ; i < 0x70 ; i += 0x10) {
45 printk("PSC #%d: IFR = 0x%02X IER = 0x%02X\n",
46 i >> 4,
47 (int) psc_read_byte(pIFRbase + i),
48 (int) psc_read_byte(pIERbase + i));
49 }
50}
51
52/*
53 * Try to kill all DMA channels on the PSC. Not sure how this his
54 * supposed to work; this is code lifted from macmace.c and then
55 * expanded to cover what I think are the other 7 channels.
56 */
57
58void psc_dma_die_die_die(void)
59{
60 int i;
61
62 printk("Killing all PSC DMA channels...");
63 for (i = 0 ; i < 9 ; i++) {
64 psc_write_word(PSC_CTL_BASE + (i << 4), 0x8800);
65 psc_write_word(PSC_CTL_BASE + (i << 4), 0x1000);
66 psc_write_word(PSC_CMD_BASE + (i << 5), 0x1100);
67 psc_write_word(PSC_CMD_BASE + (i << 5) + 0x10, 0x1100);
68 }
69 printk("done!\n");
70}
71
72/*
73 * Initialize the PSC. For now this just involves shutting down all
74 * interrupt sources using the IERs.
75 */
76
77void __init psc_init(void)
78{
79 int i;
80
81 if (macintosh_config->ident != MAC_MODEL_C660
82 && macintosh_config->ident != MAC_MODEL_Q840)
83 {
84 psc = NULL;
85 psc_present = 0;
86 return;
87 }
88
89 /*
90 * The PSC is always at the same spot, but using psc
91 * keeps things consisant with the psc_xxxx functions.
92 */
93
94 psc = (void *) PSC_BASE;
95 psc_present = 1;
96
97 printk("PSC detected at %p\n", psc);
98
99 psc_dma_die_die_die();
100
101#ifdef DEBUG_PSC
102 psc_debug_dump();
103#endif
104 /*
105 * Mask and clear all possible interrupts
106 */
107
108 for (i = 0x30 ; i < 0x70 ; i += 0x10) {
109 psc_write_byte(pIERbase + i, 0x0F);
110 psc_write_byte(pIFRbase + i, 0x0F);
111 }
112}
113
114/*
115 * Register the PSC interrupt dispatchers for autovector interrupts 3-6.
116 */
117
118void __init psc_register_interrupts(void)
119{
120 cpu_request_irq(3, psc_irq, IRQ_FLG_LOCK, "psc3", (void *) 0x30);
121 cpu_request_irq(4, psc_irq, IRQ_FLG_LOCK, "psc4", (void *) 0x40);
122 cpu_request_irq(5, psc_irq, IRQ_FLG_LOCK, "psc5", (void *) 0x50);
123 cpu_request_irq(6, psc_irq, IRQ_FLG_LOCK, "psc6", (void *) 0x60);
124}
125
126/*
127 * PSC interrupt handler. It's a lot like the VIA interrupt handler.
128 */
129
130irqreturn_t psc_irq(int irq, void *dev_id, struct pt_regs *regs)
131{
132 int pIFR = pIFRbase + ((int) dev_id);
133 int pIER = pIERbase + ((int) dev_id);
134 int base_irq;
135 int irq_bit,i;
136 unsigned char events;
137
138 base_irq = irq << 3;
139
140#ifdef DEBUG_IRQS
141 printk("psc_irq: irq %d pIFR = 0x%02X pIER = 0x%02X\n",
142 irq, (int) psc_read_byte(pIFR), (int) psc_read_byte(pIER));
143#endif
144
145 events = psc_read_byte(pIFR) & psc_read_byte(pIER) & 0xF;
146 if (!events)
147 return IRQ_NONE;
148
149 for (i = 0, irq_bit = 1 ; i < 4 ; i++, irq_bit <<= 1) {
150 if (events & irq_bit) {
151 psc_write_byte(pIER, irq_bit);
152 mac_do_irq_list(base_irq + i, regs);
153 psc_write_byte(pIFR, irq_bit);
154 psc_write_byte(pIER, irq_bit | 0x80);
155 }
156 }
157 return IRQ_HANDLED;
158}
159
160void psc_irq_enable(int irq) {
161 int irq_src = IRQ_SRC(irq);
162 int irq_idx = IRQ_IDX(irq);
163 int pIER = pIERbase + (irq_src << 4);
164
165#ifdef DEBUG_IRQUSE
166 printk("psc_irq_enable(%d)\n", irq);
167#endif
168 psc_write_byte(pIER, (1 << irq_idx) | 0x80);
169}
170
171void psc_irq_disable(int irq) {
172 int irq_src = IRQ_SRC(irq);
173 int irq_idx = IRQ_IDX(irq);
174 int pIER = pIERbase + (irq_src << 4);
175
176#ifdef DEBUG_IRQUSE
177 printk("psc_irq_disable(%d)\n", irq);
178#endif
179 psc_write_byte(pIER, 1 << irq_idx);
180}
181
182void psc_irq_clear(int irq) {
183 int irq_src = IRQ_SRC(irq);
184 int irq_idx = IRQ_IDX(irq);
185 int pIFR = pIERbase + (irq_src << 4);
186
187 psc_write_byte(pIFR, 1 << irq_idx);
188}
189
190int psc_irq_pending(int irq)
191{
192 int irq_src = IRQ_SRC(irq);
193 int irq_idx = IRQ_IDX(irq);
194 int pIFR = pIERbase + (irq_src << 4);
195
196 return psc_read_byte(pIFR) & (1 << irq_idx);
197}