1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * External Interrupt Controller on Spider South Bridge |
4 | * |
5 | * (C) Copyright IBM Deutschland Entwicklung GmbH 2005 |
6 | * |
7 | * Author: Arnd Bergmann <arndb@de.ibm.com> |
8 | */ |
9 | |
10 | #include <linux/interrupt.h> |
11 | #include <linux/irq.h> |
12 | #include <linux/ioport.h> |
13 | #include <linux/of_address.h> |
14 | #include <linux/of_irq.h> |
15 | #include <linux/pgtable.h> |
16 | |
17 | #include <asm/io.h> |
18 | |
19 | #include "interrupt.h" |
20 | |
21 | /* register layout taken from Spider spec, table 7.4-4 */ |
22 | enum { |
23 | TIR_DEN = 0x004, /* Detection Enable Register */ |
24 | TIR_MSK = 0x084, /* Mask Level Register */ |
25 | TIR_EDC = 0x0c0, /* Edge Detection Clear Register */ |
26 | TIR_PNDA = 0x100, /* Pending Register A */ |
27 | TIR_PNDB = 0x104, /* Pending Register B */ |
28 | TIR_CS = 0x144, /* Current Status Register */ |
29 | TIR_LCSA = 0x150, /* Level Current Status Register A */ |
30 | TIR_LCSB = 0x154, /* Level Current Status Register B */ |
31 | TIR_LCSC = 0x158, /* Level Current Status Register C */ |
32 | TIR_LCSD = 0x15c, /* Level Current Status Register D */ |
33 | TIR_CFGA = 0x200, /* Setting Register A0 */ |
34 | TIR_CFGB = 0x204, /* Setting Register B0 */ |
35 | /* 0x208 ... 0x3ff Setting Register An/Bn */ |
36 | TIR_PPNDA = 0x400, /* Packet Pending Register A */ |
37 | TIR_PPNDB = 0x404, /* Packet Pending Register B */ |
38 | TIR_PIERA = 0x408, /* Packet Output Error Register A */ |
39 | TIR_PIERB = 0x40c, /* Packet Output Error Register B */ |
40 | TIR_PIEN = 0x444, /* Packet Output Enable Register */ |
41 | TIR_PIPND = 0x454, /* Packet Output Pending Register */ |
42 | TIRDID = 0x484, /* Spider Device ID Register */ |
43 | REISTIM = 0x500, /* Reissue Command Timeout Time Setting */ |
44 | REISTIMEN = 0x504, /* Reissue Command Timeout Setting */ |
45 | REISWAITEN = 0x508, /* Reissue Wait Control*/ |
46 | }; |
47 | |
48 | #define SPIDER_CHIP_COUNT 4 |
49 | #define SPIDER_SRC_COUNT 64 |
50 | #define SPIDER_IRQ_INVALID 63 |
51 | |
52 | struct spider_pic { |
53 | struct irq_domain *host; |
54 | void __iomem *regs; |
55 | unsigned int node_id; |
56 | }; |
57 | static struct spider_pic spider_pics[SPIDER_CHIP_COUNT]; |
58 | |
59 | static struct spider_pic *spider_irq_data_to_pic(struct irq_data *d) |
60 | { |
61 | return irq_data_get_irq_chip_data(d); |
62 | } |
63 | |
64 | static void __iomem *spider_get_irq_config(struct spider_pic *pic, |
65 | unsigned int src) |
66 | { |
67 | return pic->regs + TIR_CFGA + 8 * src; |
68 | } |
69 | |
70 | static void spider_unmask_irq(struct irq_data *d) |
71 | { |
72 | struct spider_pic *pic = spider_irq_data_to_pic(d); |
73 | void __iomem *cfg = spider_get_irq_config(pic, src: irqd_to_hwirq(d)); |
74 | |
75 | out_be32(cfg, in_be32(cfg) | 0x30000000u); |
76 | } |
77 | |
78 | static void spider_mask_irq(struct irq_data *d) |
79 | { |
80 | struct spider_pic *pic = spider_irq_data_to_pic(d); |
81 | void __iomem *cfg = spider_get_irq_config(pic, src: irqd_to_hwirq(d)); |
82 | |
83 | out_be32(cfg, in_be32(cfg) & ~0x30000000u); |
84 | } |
85 | |
86 | static void spider_ack_irq(struct irq_data *d) |
87 | { |
88 | struct spider_pic *pic = spider_irq_data_to_pic(d); |
89 | unsigned int src = irqd_to_hwirq(d); |
90 | |
91 | /* Reset edge detection logic if necessary |
92 | */ |
93 | if (irqd_is_level_type(d)) |
94 | return; |
95 | |
96 | /* Only interrupts 47 to 50 can be set to edge */ |
97 | if (src < 47 || src > 50) |
98 | return; |
99 | |
100 | /* Perform the clear of the edge logic */ |
101 | out_be32(pic->regs + TIR_EDC, 0x100 | (src & 0xf)); |
102 | } |
103 | |
104 | static int spider_set_irq_type(struct irq_data *d, unsigned int type) |
105 | { |
106 | unsigned int sense = type & IRQ_TYPE_SENSE_MASK; |
107 | struct spider_pic *pic = spider_irq_data_to_pic(d); |
108 | unsigned int hw = irqd_to_hwirq(d); |
109 | void __iomem *cfg = spider_get_irq_config(pic, src: hw); |
110 | u32 old_mask; |
111 | u32 ic; |
112 | |
113 | /* Note that only level high is supported for most interrupts */ |
114 | if (sense != IRQ_TYPE_NONE && sense != IRQ_TYPE_LEVEL_HIGH && |
115 | (hw < 47 || hw > 50)) |
116 | return -EINVAL; |
117 | |
118 | /* Decode sense type */ |
119 | switch(sense) { |
120 | case IRQ_TYPE_EDGE_RISING: |
121 | ic = 0x3; |
122 | break; |
123 | case IRQ_TYPE_EDGE_FALLING: |
124 | ic = 0x2; |
125 | break; |
126 | case IRQ_TYPE_LEVEL_LOW: |
127 | ic = 0x0; |
128 | break; |
129 | case IRQ_TYPE_LEVEL_HIGH: |
130 | case IRQ_TYPE_NONE: |
131 | ic = 0x1; |
132 | break; |
133 | default: |
134 | return -EINVAL; |
135 | } |
136 | |
137 | /* Configure the source. One gross hack that was there before and |
138 | * that I've kept around is the priority to the BE which I set to |
139 | * be the same as the interrupt source number. I don't know whether |
140 | * that's supposed to make any kind of sense however, we'll have to |
141 | * decide that, but for now, I'm not changing the behaviour. |
142 | */ |
143 | old_mask = in_be32(cfg) & 0x30000000u; |
144 | out_be32(cfg, old_mask | (ic << 24) | (0x7 << 16) | |
145 | (pic->node_id << 4) | 0xe); |
146 | out_be32(cfg + 4, (0x2 << 16) | (hw & 0xff)); |
147 | |
148 | return 0; |
149 | } |
150 | |
151 | static struct irq_chip spider_pic = { |
152 | .name = "SPIDER" , |
153 | .irq_unmask = spider_unmask_irq, |
154 | .irq_mask = spider_mask_irq, |
155 | .irq_ack = spider_ack_irq, |
156 | .irq_set_type = spider_set_irq_type, |
157 | }; |
158 | |
159 | static int spider_host_map(struct irq_domain *h, unsigned int virq, |
160 | irq_hw_number_t hw) |
161 | { |
162 | irq_set_chip_data(irq: virq, data: h->host_data); |
163 | irq_set_chip_and_handler(irq: virq, chip: &spider_pic, handle: handle_level_irq); |
164 | |
165 | /* Set default irq type */ |
166 | irq_set_irq_type(irq: virq, type: IRQ_TYPE_NONE); |
167 | |
168 | return 0; |
169 | } |
170 | |
171 | static int spider_host_xlate(struct irq_domain *h, struct device_node *ct, |
172 | const u32 *intspec, unsigned int intsize, |
173 | irq_hw_number_t *out_hwirq, unsigned int *out_flags) |
174 | |
175 | { |
176 | /* Spider interrupts have 2 cells, first is the interrupt source, |
177 | * second, well, I don't know for sure yet ... We mask the top bits |
178 | * because old device-trees encode a node number in there |
179 | */ |
180 | *out_hwirq = intspec[0] & 0x3f; |
181 | *out_flags = IRQ_TYPE_LEVEL_HIGH; |
182 | return 0; |
183 | } |
184 | |
185 | static const struct irq_domain_ops spider_host_ops = { |
186 | .map = spider_host_map, |
187 | .xlate = spider_host_xlate, |
188 | }; |
189 | |
190 | static void spider_irq_cascade(struct irq_desc *desc) |
191 | { |
192 | struct irq_chip *chip = irq_desc_get_chip(desc); |
193 | struct spider_pic *pic = irq_desc_get_handler_data(desc); |
194 | unsigned int cs; |
195 | |
196 | cs = in_be32(pic->regs + TIR_CS) >> 24; |
197 | if (cs != SPIDER_IRQ_INVALID) |
198 | generic_handle_domain_irq(domain: pic->host, hwirq: cs); |
199 | |
200 | chip->irq_eoi(&desc->irq_data); |
201 | } |
202 | |
203 | /* For hooking up the cascade we have a problem. Our device-tree is |
204 | * crap and we don't know on which BE iic interrupt we are hooked on at |
205 | * least not the "standard" way. We can reconstitute it based on two |
206 | * informations though: which BE node we are connected to and whether |
207 | * we are connected to IOIF0 or IOIF1. Right now, we really only care |
208 | * about the IBM cell blade and we know that its firmware gives us an |
209 | * interrupt-map property which is pretty strange. |
210 | */ |
211 | static unsigned int __init spider_find_cascade_and_node(struct spider_pic *pic) |
212 | { |
213 | unsigned int virq; |
214 | const u32 *imap, *tmp; |
215 | int imaplen, intsize, unit; |
216 | struct device_node *iic; |
217 | struct device_node *of_node; |
218 | |
219 | of_node = irq_domain_get_of_node(d: pic->host); |
220 | |
221 | /* First, we check whether we have a real "interrupts" in the device |
222 | * tree in case the device-tree is ever fixed |
223 | */ |
224 | virq = irq_of_parse_and_map(node: of_node, index: 0); |
225 | if (virq) |
226 | return virq; |
227 | |
228 | /* Now do the horrible hacks */ |
229 | tmp = of_get_property(node: of_node, name: "#interrupt-cells" , NULL); |
230 | if (tmp == NULL) |
231 | return 0; |
232 | intsize = *tmp; |
233 | imap = of_get_property(node: of_node, name: "interrupt-map" , lenp: &imaplen); |
234 | if (imap == NULL || imaplen < (intsize + 1)) |
235 | return 0; |
236 | iic = of_find_node_by_phandle(handle: imap[intsize]); |
237 | if (iic == NULL) |
238 | return 0; |
239 | imap += intsize + 1; |
240 | tmp = of_get_property(node: iic, name: "#interrupt-cells" , NULL); |
241 | if (tmp == NULL) { |
242 | of_node_put(node: iic); |
243 | return 0; |
244 | } |
245 | intsize = *tmp; |
246 | /* Assume unit is last entry of interrupt specifier */ |
247 | unit = imap[intsize - 1]; |
248 | /* Ok, we have a unit, now let's try to get the node */ |
249 | tmp = of_get_property(node: iic, name: "ibm,interrupt-server-ranges" , NULL); |
250 | if (tmp == NULL) { |
251 | of_node_put(node: iic); |
252 | return 0; |
253 | } |
254 | /* ugly as hell but works for now */ |
255 | pic->node_id = (*tmp) >> 1; |
256 | of_node_put(node: iic); |
257 | |
258 | /* Ok, now let's get cracking. You may ask me why I just didn't match |
259 | * the iic host from the iic OF node, but that way I'm still compatible |
260 | * with really really old old firmwares for which we don't have a node |
261 | */ |
262 | /* Manufacture an IIC interrupt number of class 2 */ |
263 | virq = irq_create_mapping(NULL, |
264 | hwirq: (pic->node_id << IIC_IRQ_NODE_SHIFT) | |
265 | (2 << IIC_IRQ_CLASS_SHIFT) | |
266 | unit); |
267 | if (!virq) |
268 | printk(KERN_ERR "spider_pic: failed to map cascade !" ); |
269 | return virq; |
270 | } |
271 | |
272 | |
273 | static void __init spider_init_one(struct device_node *of_node, int chip, |
274 | unsigned long addr) |
275 | { |
276 | struct spider_pic *pic = &spider_pics[chip]; |
277 | int i, virq; |
278 | |
279 | /* Map registers */ |
280 | pic->regs = ioremap(offset: addr, size: 0x1000); |
281 | if (pic->regs == NULL) |
282 | panic(fmt: "spider_pic: can't map registers !" ); |
283 | |
284 | /* Allocate a host */ |
285 | pic->host = irq_domain_add_linear(of_node, SPIDER_SRC_COUNT, |
286 | ops: &spider_host_ops, host_data: pic); |
287 | if (pic->host == NULL) |
288 | panic(fmt: "spider_pic: can't allocate irq host !" ); |
289 | |
290 | /* Go through all sources and disable them */ |
291 | for (i = 0; i < SPIDER_SRC_COUNT; i++) { |
292 | void __iomem *cfg = pic->regs + TIR_CFGA + 8 * i; |
293 | out_be32(cfg, in_be32(cfg) & ~0x30000000u); |
294 | } |
295 | |
296 | /* do not mask any interrupts because of level */ |
297 | out_be32(pic->regs + TIR_MSK, 0x0); |
298 | |
299 | /* enable interrupt packets to be output */ |
300 | out_be32(pic->regs + TIR_PIEN, in_be32(pic->regs + TIR_PIEN) | 0x1); |
301 | |
302 | /* Hook up the cascade interrupt to the iic and nodeid */ |
303 | virq = spider_find_cascade_and_node(pic); |
304 | if (!virq) |
305 | return; |
306 | irq_set_handler_data(irq: virq, data: pic); |
307 | irq_set_chained_handler(irq: virq, handle: spider_irq_cascade); |
308 | |
309 | printk(KERN_INFO "spider_pic: node %d, addr: 0x%lx %pOF\n" , |
310 | pic->node_id, addr, of_node); |
311 | |
312 | /* Enable the interrupt detection enable bit. Do this last! */ |
313 | out_be32(pic->regs + TIR_DEN, in_be32(pic->regs + TIR_DEN) | 0x1); |
314 | } |
315 | |
316 | void __init spider_init_IRQ(void) |
317 | { |
318 | struct resource r; |
319 | struct device_node *dn; |
320 | int chip = 0; |
321 | |
322 | /* XXX node numbers are totally bogus. We _hope_ we get the device |
323 | * nodes in the right order here but that's definitely not guaranteed, |
324 | * we need to get the node from the device tree instead. |
325 | * There is currently no proper property for it (but our whole |
326 | * device-tree is bogus anyway) so all we can do is pray or maybe test |
327 | * the address and deduce the node-id |
328 | */ |
329 | for_each_node_by_name(dn, "interrupt-controller" ) { |
330 | if (of_device_is_compatible(device: dn, "CBEA,platform-spider-pic" )) { |
331 | if (of_address_to_resource(dev: dn, index: 0, r: &r)) { |
332 | printk(KERN_WARNING "spider-pic: Failed\n" ); |
333 | continue; |
334 | } |
335 | } else if (of_device_is_compatible(device: dn, "sti,platform-spider-pic" ) |
336 | && (chip < 2)) { |
337 | static long hard_coded_pics[] = |
338 | { 0x24000008000ul, 0x34000008000ul}; |
339 | r.start = hard_coded_pics[chip]; |
340 | } else |
341 | continue; |
342 | spider_init_one(of_node: dn, chip: chip++, addr: r.start); |
343 | } |
344 | } |
345 | |