xref: /linux/arch/mips/kernel/mips-mt.c (revision b6ebbac51bedf9e98e837688bc838f400196da5e)
1 /*
2  * General MIPS MT support routines, usable in AP/SP and SMVP.
3  * Copyright (C) 2005 Mips Technologies, Inc
4  */
5 
6 #include <linux/device.h>
7 #include <linux/kernel.h>
8 #include <linux/sched.h>
9 #include <linux/export.h>
10 #include <linux/interrupt.h>
11 #include <linux/security.h>
12 
13 #include <asm/cpu.h>
14 #include <asm/processor.h>
15 #include <linux/atomic.h>
16 #include <asm/hardirq.h>
17 #include <asm/mmu_context.h>
18 #include <asm/mipsmtregs.h>
19 #include <asm/r4kcache.h>
20 #include <asm/cacheflush.h>
21 
22 int vpelimit;
23 
24 static int __init maxvpes(char *str)
25 {
26 	get_option(&str, &vpelimit);
27 
28 	return 1;
29 }
30 
31 __setup("maxvpes=", maxvpes);
32 
33 int tclimit;
34 
35 static int __init maxtcs(char *str)
36 {
37 	get_option(&str, &tclimit);
38 
39 	return 1;
40 }
41 
42 __setup("maxtcs=", maxtcs);
43 
44 /*
45  * Dump new MIPS MT state for the core. Does not leave TCs halted.
46  * Takes an argument which taken to be a pre-call MVPControl value.
47  */
48 
49 void mips_mt_regdump(unsigned long mvpctl)
50 {
51 	unsigned long flags;
52 	unsigned long vpflags;
53 	unsigned long mvpconf0;
54 	int nvpe;
55 	int ntc;
56 	int i;
57 	int tc;
58 	unsigned long haltval;
59 	unsigned long tcstatval;
60 
61 	local_irq_save(flags);
62 	vpflags = dvpe();
63 	printk("=== MIPS MT State Dump ===\n");
64 	printk("-- Global State --\n");
65 	printk("   MVPControl Passed: %08lx\n", mvpctl);
66 	printk("   MVPControl Read: %08lx\n", vpflags);
67 	printk("   MVPConf0 : %08lx\n", (mvpconf0 = read_c0_mvpconf0()));
68 	nvpe = ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
69 	ntc = ((mvpconf0 & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT) + 1;
70 	printk("-- per-VPE State --\n");
71 	for (i = 0; i < nvpe; i++) {
72 		for (tc = 0; tc < ntc; tc++) {
73 			settc(tc);
74 			if ((read_tc_c0_tcbind() & TCBIND_CURVPE) == i) {
75 				printk("  VPE %d\n", i);
76 				printk("   VPEControl : %08lx\n",
77 				       read_vpe_c0_vpecontrol());
78 				printk("   VPEConf0 : %08lx\n",
79 				       read_vpe_c0_vpeconf0());
80 				printk("   VPE%d.Status : %08lx\n",
81 				       i, read_vpe_c0_status());
82 				printk("   VPE%d.EPC : %08lx %pS\n",
83 				       i, read_vpe_c0_epc(),
84 				       (void *) read_vpe_c0_epc());
85 				printk("   VPE%d.Cause : %08lx\n",
86 				       i, read_vpe_c0_cause());
87 				printk("   VPE%d.Config7 : %08lx\n",
88 				       i, read_vpe_c0_config7());
89 				break; /* Next VPE */
90 			}
91 		}
92 	}
93 	printk("-- per-TC State --\n");
94 	for (tc = 0; tc < ntc; tc++) {
95 		settc(tc);
96 		if (read_tc_c0_tcbind() == read_c0_tcbind()) {
97 			/* Are we dumping ourself?  */
98 			haltval = 0; /* Then we're not halted, and mustn't be */
99 			tcstatval = flags; /* And pre-dump TCStatus is flags */
100 			printk("  TC %d (current TC with VPE EPC above)\n", tc);
101 		} else {
102 			haltval = read_tc_c0_tchalt();
103 			write_tc_c0_tchalt(1);
104 			tcstatval = read_tc_c0_tcstatus();
105 			printk("  TC %d\n", tc);
106 		}
107 		printk("   TCStatus : %08lx\n", tcstatval);
108 		printk("   TCBind : %08lx\n", read_tc_c0_tcbind());
109 		printk("   TCRestart : %08lx %pS\n",
110 		       read_tc_c0_tcrestart(), (void *) read_tc_c0_tcrestart());
111 		printk("   TCHalt : %08lx\n", haltval);
112 		printk("   TCContext : %08lx\n", read_tc_c0_tccontext());
113 		if (!haltval)
114 			write_tc_c0_tchalt(0);
115 	}
116 	printk("===========================\n");
117 	evpe(vpflags);
118 	local_irq_restore(flags);
119 }
120 
121 static int mt_opt_norps;
122 static int mt_opt_rpsctl = -1;
123 static int mt_opt_nblsu = -1;
124 static int mt_opt_forceconfig7;
125 static int mt_opt_config7 = -1;
126 
127 static int __init rps_disable(char *s)
128 {
129 	mt_opt_norps = 1;
130 	return 1;
131 }
132 __setup("norps", rps_disable);
133 
134 static int __init rpsctl_set(char *str)
135 {
136 	get_option(&str, &mt_opt_rpsctl);
137 	return 1;
138 }
139 __setup("rpsctl=", rpsctl_set);
140 
141 static int __init nblsu_set(char *str)
142 {
143 	get_option(&str, &mt_opt_nblsu);
144 	return 1;
145 }
146 __setup("nblsu=", nblsu_set);
147 
148 static int __init config7_set(char *str)
149 {
150 	get_option(&str, &mt_opt_config7);
151 	mt_opt_forceconfig7 = 1;
152 	return 1;
153 }
154 __setup("config7=", config7_set);
155 
156 /* Experimental cache flush control parameters that should go away some day */
157 int mt_protiflush;
158 int mt_protdflush;
159 int mt_n_iflushes = 1;
160 int mt_n_dflushes = 1;
161 
162 static int __init set_protiflush(char *s)
163 {
164 	mt_protiflush = 1;
165 	return 1;
166 }
167 __setup("protiflush", set_protiflush);
168 
169 static int __init set_protdflush(char *s)
170 {
171 	mt_protdflush = 1;
172 	return 1;
173 }
174 __setup("protdflush", set_protdflush);
175 
176 static int __init niflush(char *s)
177 {
178 	get_option(&s, &mt_n_iflushes);
179 	return 1;
180 }
181 __setup("niflush=", niflush);
182 
183 static int __init ndflush(char *s)
184 {
185 	get_option(&s, &mt_n_dflushes);
186 	return 1;
187 }
188 __setup("ndflush=", ndflush);
189 
190 static unsigned int itc_base;
191 
192 static int __init set_itc_base(char *str)
193 {
194 	get_option(&str, &itc_base);
195 	return 1;
196 }
197 
198 __setup("itcbase=", set_itc_base);
199 
200 void mips_mt_set_cpuoptions(void)
201 {
202 	unsigned int oconfig7 = read_c0_config7();
203 	unsigned int nconfig7 = oconfig7;
204 
205 	if (mt_opt_norps) {
206 		printk("\"norps\" option deprecated: use \"rpsctl=\"\n");
207 	}
208 	if (mt_opt_rpsctl >= 0) {
209 		printk("34K return prediction stack override set to %d.\n",
210 			mt_opt_rpsctl);
211 		if (mt_opt_rpsctl)
212 			nconfig7 |= (1 << 2);
213 		else
214 			nconfig7 &= ~(1 << 2);
215 	}
216 	if (mt_opt_nblsu >= 0) {
217 		printk("34K ALU/LSU sync override set to %d.\n", mt_opt_nblsu);
218 		if (mt_opt_nblsu)
219 			nconfig7 |= (1 << 5);
220 		else
221 			nconfig7 &= ~(1 << 5);
222 	}
223 	if (mt_opt_forceconfig7) {
224 		printk("CP0.Config7 forced to 0x%08x.\n", mt_opt_config7);
225 		nconfig7 = mt_opt_config7;
226 	}
227 	if (oconfig7 != nconfig7) {
228 		__asm__ __volatile("sync");
229 		write_c0_config7(nconfig7);
230 		ehb();
231 		printk("Config7: 0x%08x\n", read_c0_config7());
232 	}
233 
234 	/* Report Cache management debug options */
235 	if (mt_protiflush)
236 		printk("I-cache flushes single-threaded\n");
237 	if (mt_protdflush)
238 		printk("D-cache flushes single-threaded\n");
239 	if (mt_n_iflushes != 1)
240 		printk("I-Cache Flushes Repeated %d times\n", mt_n_iflushes);
241 	if (mt_n_dflushes != 1)
242 		printk("D-Cache Flushes Repeated %d times\n", mt_n_dflushes);
243 
244 	if (itc_base != 0) {
245 		/*
246 		 * Configure ITC mapping.  This code is very
247 		 * specific to the 34K core family, which uses
248 		 * a special mode bit ("ITC") in the ErrCtl
249 		 * register to enable access to ITC control
250 		 * registers via cache "tag" operations.
251 		 */
252 		unsigned long ectlval;
253 		unsigned long itcblkgrn;
254 
255 		/* ErrCtl register is known as "ecc" to Linux */
256 		ectlval = read_c0_ecc();
257 		write_c0_ecc(ectlval | (0x1 << 26));
258 		ehb();
259 #define INDEX_0 (0x80000000)
260 #define INDEX_8 (0x80000008)
261 		/* Read "cache tag" for Dcache pseudo-index 8 */
262 		cache_op(Index_Load_Tag_D, INDEX_8);
263 		ehb();
264 		itcblkgrn = read_c0_dtaglo();
265 		itcblkgrn &= 0xfffe0000;
266 		/* Set for 128 byte pitch of ITC cells */
267 		itcblkgrn |= 0x00000c00;
268 		/* Stage in Tag register */
269 		write_c0_dtaglo(itcblkgrn);
270 		ehb();
271 		/* Write out to ITU with CACHE op */
272 		cache_op(Index_Store_Tag_D, INDEX_8);
273 		/* Now set base address, and turn ITC on with 0x1 bit */
274 		write_c0_dtaglo((itc_base & 0xfffffc00) | 0x1 );
275 		ehb();
276 		/* Write out to ITU with CACHE op */
277 		cache_op(Index_Store_Tag_D, INDEX_0);
278 		write_c0_ecc(ectlval);
279 		ehb();
280 		printk("Mapped %ld ITC cells starting at 0x%08x\n",
281 			((itcblkgrn & 0x7fe00000) >> 20), itc_base);
282 	}
283 }
284 
285 /*
286  * Function to protect cache flushes from concurrent execution
287  * depends on MP software model chosen.
288  */
289 
290 void mt_cflush_lockdown(void)
291 {
292 	/* FILL IN VSMP and AP/SP VERSIONS HERE */
293 }
294 
295 void mt_cflush_release(void)
296 {
297 	/* FILL IN VSMP and AP/SP VERSIONS HERE */
298 }
299 
300 struct class *mt_class;
301 
302 static int __init mt_init(void)
303 {
304 	struct class *mtc;
305 
306 	mtc = class_create(THIS_MODULE, "mt");
307 	if (IS_ERR(mtc))
308 		return PTR_ERR(mtc);
309 
310 	mt_class = mtc;
311 
312 	return 0;
313 }
314 
315 subsys_initcall(mt_init);
316