xref: /openbmc/linux/drivers/ssb/driver_mipscore.c (revision 54cbac81)
1 /*
2  * Sonics Silicon Backplane
3  * Broadcom MIPS core driver
4  *
5  * Copyright 2005, Broadcom Corporation
6  * Copyright 2006, 2007, Michael Buesch <m@bues.ch>
7  *
8  * Licensed under the GNU/GPL. See COPYING for details.
9  */
10 
11 #include <linux/ssb/ssb.h>
12 
13 #include <linux/serial.h>
14 #include <linux/serial_core.h>
15 #include <linux/serial_reg.h>
16 #include <linux/time.h>
17 
18 #include "ssb_private.h"
19 
20 
21 static inline u32 mips_read32(struct ssb_mipscore *mcore,
22 			      u16 offset)
23 {
24 	return ssb_read32(mcore->dev, offset);
25 }
26 
27 static inline void mips_write32(struct ssb_mipscore *mcore,
28 				u16 offset,
29 				u32 value)
30 {
31 	ssb_write32(mcore->dev, offset, value);
32 }
33 
34 static const u32 ipsflag_irq_mask[] = {
35 	0,
36 	SSB_IPSFLAG_IRQ1,
37 	SSB_IPSFLAG_IRQ2,
38 	SSB_IPSFLAG_IRQ3,
39 	SSB_IPSFLAG_IRQ4,
40 };
41 
42 static const u32 ipsflag_irq_shift[] = {
43 	0,
44 	SSB_IPSFLAG_IRQ1_SHIFT,
45 	SSB_IPSFLAG_IRQ2_SHIFT,
46 	SSB_IPSFLAG_IRQ3_SHIFT,
47 	SSB_IPSFLAG_IRQ4_SHIFT,
48 };
49 
50 static inline u32 ssb_irqflag(struct ssb_device *dev)
51 {
52 	u32 tpsflag = ssb_read32(dev, SSB_TPSFLAG);
53 	if (tpsflag)
54 		return ssb_read32(dev, SSB_TPSFLAG) & SSB_TPSFLAG_BPFLAG;
55 	else
56 		/* not irq supported */
57 		return 0x3f;
58 }
59 
60 static struct ssb_device *find_device(struct ssb_device *rdev, int irqflag)
61 {
62 	struct ssb_bus *bus = rdev->bus;
63 	int i;
64 	for (i = 0; i < bus->nr_devices; i++) {
65 		struct ssb_device *dev;
66 		dev = &(bus->devices[i]);
67 		if (ssb_irqflag(dev) == irqflag)
68 			return dev;
69 	}
70 	return NULL;
71 }
72 
73 /* Get the MIPS IRQ assignment for a specified device.
74  * If unassigned, 0 is returned.
75  * If disabled, 5 is returned.
76  * If not supported, 6 is returned.
77  */
78 unsigned int ssb_mips_irq(struct ssb_device *dev)
79 {
80 	struct ssb_bus *bus = dev->bus;
81 	struct ssb_device *mdev = bus->mipscore.dev;
82 	u32 irqflag;
83 	u32 ipsflag;
84 	u32 tmp;
85 	unsigned int irq;
86 
87 	irqflag = ssb_irqflag(dev);
88 	if (irqflag == 0x3f)
89 		return 6;
90 	ipsflag = ssb_read32(bus->mipscore.dev, SSB_IPSFLAG);
91 	for (irq = 1; irq <= 4; irq++) {
92 		tmp = ((ipsflag & ipsflag_irq_mask[irq]) >> ipsflag_irq_shift[irq]);
93 		if (tmp == irqflag)
94 			break;
95 	}
96 	if (irq	== 5) {
97 		if ((1 << irqflag) & ssb_read32(mdev, SSB_INTVEC))
98 			irq = 0;
99 	}
100 
101 	return irq;
102 }
103 
104 static void clear_irq(struct ssb_bus *bus, unsigned int irq)
105 {
106 	struct ssb_device *dev = bus->mipscore.dev;
107 
108 	/* Clear the IRQ in the MIPScore backplane registers */
109 	if (irq == 0) {
110 		ssb_write32(dev, SSB_INTVEC, 0);
111 	} else {
112 		ssb_write32(dev, SSB_IPSFLAG,
113 			    ssb_read32(dev, SSB_IPSFLAG) |
114 			    ipsflag_irq_mask[irq]);
115 	}
116 }
117 
118 static void set_irq(struct ssb_device *dev, unsigned int irq)
119 {
120 	unsigned int oldirq = ssb_mips_irq(dev);
121 	struct ssb_bus *bus = dev->bus;
122 	struct ssb_device *mdev = bus->mipscore.dev;
123 	u32 irqflag = ssb_irqflag(dev);
124 
125 	BUG_ON(oldirq == 6);
126 
127 	dev->irq = irq + 2;
128 
129 	/* clear the old irq */
130 	if (oldirq == 0)
131 		ssb_write32(mdev, SSB_INTVEC, (~(1 << irqflag) & ssb_read32(mdev, SSB_INTVEC)));
132 	else if (oldirq != 5)
133 		clear_irq(bus, oldirq);
134 
135 	/* assign the new one */
136 	if (irq == 0) {
137 		ssb_write32(mdev, SSB_INTVEC, ((1 << irqflag) | ssb_read32(mdev, SSB_INTVEC)));
138 	} else {
139 		u32 ipsflag = ssb_read32(mdev, SSB_IPSFLAG);
140 		if ((ipsflag & ipsflag_irq_mask[irq]) != ipsflag_irq_mask[irq]) {
141 			u32 oldipsflag = (ipsflag & ipsflag_irq_mask[irq]) >> ipsflag_irq_shift[irq];
142 			struct ssb_device *olddev = find_device(dev, oldipsflag);
143 			if (olddev)
144 				set_irq(olddev, 0);
145 		}
146 		irqflag <<= ipsflag_irq_shift[irq];
147 		irqflag |= (ipsflag & ~ipsflag_irq_mask[irq]);
148 		ssb_write32(mdev, SSB_IPSFLAG, irqflag);
149 	}
150 	ssb_dprintk(KERN_INFO PFX
151 		    "set_irq: core 0x%04x, irq %d => %d\n",
152 		    dev->id.coreid, oldirq+2, irq+2);
153 }
154 
155 static void print_irq(struct ssb_device *dev, unsigned int irq)
156 {
157 	int i;
158 	static const char *irq_name[] = {"2(S)", "3", "4", "5", "6", "D", "I"};
159 	ssb_dprintk(KERN_INFO PFX
160 		"core 0x%04x, irq :", dev->id.coreid);
161 	for (i = 0; i <= 6; i++) {
162 		ssb_dprintk(" %s%s", irq_name[i], i==irq?"*":" ");
163 	}
164 	ssb_dprintk("\n");
165 }
166 
167 static void dump_irq(struct ssb_bus *bus)
168 {
169 	int i;
170 	for (i = 0; i < bus->nr_devices; i++) {
171 		struct ssb_device *dev;
172 		dev = &(bus->devices[i]);
173 		print_irq(dev, ssb_mips_irq(dev));
174 	}
175 }
176 
177 static void ssb_mips_serial_init(struct ssb_mipscore *mcore)
178 {
179 	struct ssb_bus *bus = mcore->dev->bus;
180 
181 	if (ssb_extif_available(&bus->extif))
182 		mcore->nr_serial_ports = ssb_extif_serial_init(&bus->extif, mcore->serial_ports);
183 	else if (ssb_chipco_available(&bus->chipco))
184 		mcore->nr_serial_ports = ssb_chipco_serial_init(&bus->chipco, mcore->serial_ports);
185 	else
186 		mcore->nr_serial_ports = 0;
187 }
188 
189 static void ssb_mips_flash_detect(struct ssb_mipscore *mcore)
190 {
191 	struct ssb_bus *bus = mcore->dev->bus;
192 
193 	/* When there is no chipcommon on the bus there is 4MB flash */
194 	if (!ssb_chipco_available(&bus->chipco)) {
195 		mcore->pflash.present = true;
196 		mcore->pflash.buswidth = 2;
197 		mcore->pflash.window = SSB_FLASH1;
198 		mcore->pflash.window_size = SSB_FLASH1_SZ;
199 		return;
200 	}
201 
202 	/* There is ChipCommon, so use it to read info about flash */
203 	switch (bus->chipco.capabilities & SSB_CHIPCO_CAP_FLASHT) {
204 	case SSB_CHIPCO_FLASHT_STSER:
205 	case SSB_CHIPCO_FLASHT_ATSER:
206 		pr_err("Serial flash not supported\n");
207 		break;
208 	case SSB_CHIPCO_FLASHT_PARA:
209 		pr_debug("Found parallel flash\n");
210 		mcore->pflash.present = true;
211 		mcore->pflash.window = SSB_FLASH2;
212 		mcore->pflash.window_size = SSB_FLASH2_SZ;
213 		if ((ssb_read32(bus->chipco.dev, SSB_CHIPCO_FLASH_CFG)
214 		               & SSB_CHIPCO_CFG_DS16) == 0)
215 			mcore->pflash.buswidth = 1;
216 		else
217 			mcore->pflash.buswidth = 2;
218 		break;
219 	}
220 }
221 
222 u32 ssb_cpu_clock(struct ssb_mipscore *mcore)
223 {
224 	struct ssb_bus *bus = mcore->dev->bus;
225 	u32 pll_type, n, m, rate = 0;
226 
227 	if (bus->chipco.capabilities & SSB_CHIPCO_CAP_PMU)
228 		return ssb_pmu_get_cpu_clock(&bus->chipco);
229 
230 	if (ssb_extif_available(&bus->extif)) {
231 		ssb_extif_get_clockcontrol(&bus->extif, &pll_type, &n, &m);
232 	} else if (ssb_chipco_available(&bus->chipco)) {
233 		ssb_chipco_get_clockcpu(&bus->chipco, &pll_type, &n, &m);
234 	} else
235 		return 0;
236 
237 	if ((pll_type == SSB_PLLTYPE_5) || (bus->chip_id == 0x5365)) {
238 		rate = 200000000;
239 	} else {
240 		rate = ssb_calc_clock_rate(pll_type, n, m);
241 	}
242 
243 	if (pll_type == SSB_PLLTYPE_6) {
244 		rate *= 2;
245 	}
246 
247 	return rate;
248 }
249 
250 void ssb_mipscore_init(struct ssb_mipscore *mcore)
251 {
252 	struct ssb_bus *bus;
253 	struct ssb_device *dev;
254 	unsigned long hz, ns;
255 	unsigned int irq, i;
256 
257 	if (!mcore->dev)
258 		return; /* We don't have a MIPS core */
259 
260 	ssb_dprintk(KERN_INFO PFX "Initializing MIPS core...\n");
261 
262 	bus = mcore->dev->bus;
263 	hz = ssb_clockspeed(bus);
264 	if (!hz)
265 		hz = 100000000;
266 	ns = 1000000000 / hz;
267 
268 	if (ssb_extif_available(&bus->extif))
269 		ssb_extif_timing_init(&bus->extif, ns);
270 	else if (ssb_chipco_available(&bus->chipco))
271 		ssb_chipco_timing_init(&bus->chipco, ns);
272 
273 	/* Assign IRQs to all cores on the bus, start with irq line 2, because serial usually takes 1 */
274 	for (irq = 2, i = 0; i < bus->nr_devices; i++) {
275 		int mips_irq;
276 		dev = &(bus->devices[i]);
277 		mips_irq = ssb_mips_irq(dev);
278 		if (mips_irq > 4)
279 			dev->irq = 0;
280 		else
281 			dev->irq = mips_irq + 2;
282 		if (dev->irq > 5)
283 			continue;
284 		switch (dev->id.coreid) {
285 		case SSB_DEV_USB11_HOST:
286 			/* shouldn't need a separate irq line for non-4710, most of them have a proper
287 			 * external usb controller on the pci */
288 			if ((bus->chip_id == 0x4710) && (irq <= 4)) {
289 				set_irq(dev, irq++);
290 			}
291 			break;
292 		case SSB_DEV_PCI:
293 		case SSB_DEV_ETHERNET:
294 		case SSB_DEV_ETHERNET_GBIT:
295 		case SSB_DEV_80211:
296 		case SSB_DEV_USB20_HOST:
297 			/* These devices get their own IRQ line if available, the rest goes on IRQ0 */
298 			if (irq <= 4) {
299 				set_irq(dev, irq++);
300 				break;
301 			}
302 			/* fallthrough */
303 		case SSB_DEV_EXTIF:
304 			set_irq(dev, 0);
305 			break;
306 		}
307 	}
308 	ssb_dprintk(KERN_INFO PFX "after irq reconfiguration\n");
309 	dump_irq(bus);
310 
311 	ssb_mips_serial_init(mcore);
312 	ssb_mips_flash_detect(mcore);
313 }
314