ARM: mmp: fix potential NULL dereference
[linux/fpc-iii.git] / arch / mips / kernel / mips-mt.c
blob6ded9bd1489cb176e11779d10e68bc4134e43488
1 /*
2 * General MIPS MT support routines, usable in AP/SP, SMVP, or SMTC kernels
3 * Copyright (C) 2005 Mips Technologies, Inc
4 */
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>
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>
22 int vpelimit;
24 static int __init maxvpes(char *str)
26 get_option(&str, &vpelimit);
28 return 1;
31 __setup("maxvpes=", maxvpes);
33 int tclimit;
35 static int __init maxtcs(char *str)
37 get_option(&str, &tclimit);
39 return 1;
42 __setup("maxtcs=", maxtcs);
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.
49 void mips_mt_regdump(unsigned long mvpctl)
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 #ifdef CONFIG_MIPS_MT_SMTC
61 void smtc_soft_dump(void);
62 #endif /* CONFIG_MIPT_MT_SMTC */
64 local_irq_save(flags);
65 vpflags = dvpe();
66 printk("=== MIPS MT State Dump ===\n");
67 printk("-- Global State --\n");
68 printk(" MVPControl Passed: %08lx\n", mvpctl);
69 printk(" MVPControl Read: %08lx\n", vpflags);
70 printk(" MVPConf0 : %08lx\n", (mvpconf0 = read_c0_mvpconf0()));
71 nvpe = ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
72 ntc = ((mvpconf0 & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT) + 1;
73 printk("-- per-VPE State --\n");
74 for (i = 0; i < nvpe; i++) {
75 for (tc = 0; tc < ntc; tc++) {
76 settc(tc);
77 if ((read_tc_c0_tcbind() & TCBIND_CURVPE) == i) {
78 printk(" VPE %d\n", i);
79 printk(" VPEControl : %08lx\n",
80 read_vpe_c0_vpecontrol());
81 printk(" VPEConf0 : %08lx\n",
82 read_vpe_c0_vpeconf0());
83 printk(" VPE%d.Status : %08lx\n",
84 i, read_vpe_c0_status());
85 printk(" VPE%d.EPC : %08lx %pS\n",
86 i, read_vpe_c0_epc(),
87 (void *) read_vpe_c0_epc());
88 printk(" VPE%d.Cause : %08lx\n",
89 i, read_vpe_c0_cause());
90 printk(" VPE%d.Config7 : %08lx\n",
91 i, read_vpe_c0_config7());
92 break; /* Next VPE */
96 printk("-- per-TC State --\n");
97 for (tc = 0; tc < ntc; tc++) {
98 settc(tc);
99 if (read_tc_c0_tcbind() == read_c0_tcbind()) {
100 /* Are we dumping ourself? */
101 haltval = 0; /* Then we're not halted, and mustn't be */
102 tcstatval = flags; /* And pre-dump TCStatus is flags */
103 printk(" TC %d (current TC with VPE EPC above)\n", tc);
104 } else {
105 haltval = read_tc_c0_tchalt();
106 write_tc_c0_tchalt(1);
107 tcstatval = read_tc_c0_tcstatus();
108 printk(" TC %d\n", tc);
110 printk(" TCStatus : %08lx\n", tcstatval);
111 printk(" TCBind : %08lx\n", read_tc_c0_tcbind());
112 printk(" TCRestart : %08lx %pS\n",
113 read_tc_c0_tcrestart(), (void *) read_tc_c0_tcrestart());
114 printk(" TCHalt : %08lx\n", haltval);
115 printk(" TCContext : %08lx\n", read_tc_c0_tccontext());
116 if (!haltval)
117 write_tc_c0_tchalt(0);
119 #ifdef CONFIG_MIPS_MT_SMTC
120 smtc_soft_dump();
121 #endif /* CONFIG_MIPT_MT_SMTC */
122 printk("===========================\n");
123 evpe(vpflags);
124 local_irq_restore(flags);
127 static int mt_opt_norps;
128 static int mt_opt_rpsctl = -1;
129 static int mt_opt_nblsu = -1;
130 static int mt_opt_forceconfig7;
131 static int mt_opt_config7 = -1;
133 static int __init rps_disable(char *s)
135 mt_opt_norps = 1;
136 return 1;
138 __setup("norps", rps_disable);
140 static int __init rpsctl_set(char *str)
142 get_option(&str, &mt_opt_rpsctl);
143 return 1;
145 __setup("rpsctl=", rpsctl_set);
147 static int __init nblsu_set(char *str)
149 get_option(&str, &mt_opt_nblsu);
150 return 1;
152 __setup("nblsu=", nblsu_set);
154 static int __init config7_set(char *str)
156 get_option(&str, &mt_opt_config7);
157 mt_opt_forceconfig7 = 1;
158 return 1;
160 __setup("config7=", config7_set);
162 /* Experimental cache flush control parameters that should go away some day */
163 int mt_protiflush;
164 int mt_protdflush;
165 int mt_n_iflushes = 1;
166 int mt_n_dflushes = 1;
168 static int __init set_protiflush(char *s)
170 mt_protiflush = 1;
171 return 1;
173 __setup("protiflush", set_protiflush);
175 static int __init set_protdflush(char *s)
177 mt_protdflush = 1;
178 return 1;
180 __setup("protdflush", set_protdflush);
182 static int __init niflush(char *s)
184 get_option(&s, &mt_n_iflushes);
185 return 1;
187 __setup("niflush=", niflush);
189 static int __init ndflush(char *s)
191 get_option(&s, &mt_n_dflushes);
192 return 1;
194 __setup("ndflush=", ndflush);
196 static unsigned int itc_base;
198 static int __init set_itc_base(char *str)
200 get_option(&str, &itc_base);
201 return 1;
204 __setup("itcbase=", set_itc_base);
206 void mips_mt_set_cpuoptions(void)
208 unsigned int oconfig7 = read_c0_config7();
209 unsigned int nconfig7 = oconfig7;
211 if (mt_opt_norps) {
212 printk("\"norps\" option deprecated: use \"rpsctl=\"\n");
214 if (mt_opt_rpsctl >= 0) {
215 printk("34K return prediction stack override set to %d.\n",
216 mt_opt_rpsctl);
217 if (mt_opt_rpsctl)
218 nconfig7 |= (1 << 2);
219 else
220 nconfig7 &= ~(1 << 2);
222 if (mt_opt_nblsu >= 0) {
223 printk("34K ALU/LSU sync override set to %d.\n", mt_opt_nblsu);
224 if (mt_opt_nblsu)
225 nconfig7 |= (1 << 5);
226 else
227 nconfig7 &= ~(1 << 5);
229 if (mt_opt_forceconfig7) {
230 printk("CP0.Config7 forced to 0x%08x.\n", mt_opt_config7);
231 nconfig7 = mt_opt_config7;
233 if (oconfig7 != nconfig7) {
234 __asm__ __volatile("sync");
235 write_c0_config7(nconfig7);
236 ehb();
237 printk("Config7: 0x%08x\n", read_c0_config7());
240 /* Report Cache management debug options */
241 if (mt_protiflush)
242 printk("I-cache flushes single-threaded\n");
243 if (mt_protdflush)
244 printk("D-cache flushes single-threaded\n");
245 if (mt_n_iflushes != 1)
246 printk("I-Cache Flushes Repeated %d times\n", mt_n_iflushes);
247 if (mt_n_dflushes != 1)
248 printk("D-Cache Flushes Repeated %d times\n", mt_n_dflushes);
250 if (itc_base != 0) {
252 * Configure ITC mapping. This code is very
253 * specific to the 34K core family, which uses
254 * a special mode bit ("ITC") in the ErrCtl
255 * register to enable access to ITC control
256 * registers via cache "tag" operations.
258 unsigned long ectlval;
259 unsigned long itcblkgrn;
261 /* ErrCtl register is known as "ecc" to Linux */
262 ectlval = read_c0_ecc();
263 write_c0_ecc(ectlval | (0x1 << 26));
264 ehb();
265 #define INDEX_0 (0x80000000)
266 #define INDEX_8 (0x80000008)
267 /* Read "cache tag" for Dcache pseudo-index 8 */
268 cache_op(Index_Load_Tag_D, INDEX_8);
269 ehb();
270 itcblkgrn = read_c0_dtaglo();
271 itcblkgrn &= 0xfffe0000;
272 /* Set for 128 byte pitch of ITC cells */
273 itcblkgrn |= 0x00000c00;
274 /* Stage in Tag register */
275 write_c0_dtaglo(itcblkgrn);
276 ehb();
277 /* Write out to ITU with CACHE op */
278 cache_op(Index_Store_Tag_D, INDEX_8);
279 /* Now set base address, and turn ITC on with 0x1 bit */
280 write_c0_dtaglo((itc_base & 0xfffffc00) | 0x1 );
281 ehb();
282 /* Write out to ITU with CACHE op */
283 cache_op(Index_Store_Tag_D, INDEX_0);
284 write_c0_ecc(ectlval);
285 ehb();
286 printk("Mapped %ld ITC cells starting at 0x%08x\n",
287 ((itcblkgrn & 0x7fe00000) >> 20), itc_base);
292 * Function to protect cache flushes from concurrent execution
293 * depends on MP software model chosen.
296 void mt_cflush_lockdown(void)
298 #ifdef CONFIG_MIPS_MT_SMTC
299 void smtc_cflush_lockdown(void);
301 smtc_cflush_lockdown();
302 #endif /* CONFIG_MIPS_MT_SMTC */
303 /* FILL IN VSMP and AP/SP VERSIONS HERE */
306 void mt_cflush_release(void)
308 #ifdef CONFIG_MIPS_MT_SMTC
309 void smtc_cflush_release(void);
311 smtc_cflush_release();
312 #endif /* CONFIG_MIPS_MT_SMTC */
313 /* FILL IN VSMP and AP/SP VERSIONS HERE */
316 struct class *mt_class;
318 static int __init mt_init(void)
320 struct class *mtc;
322 mtc = class_create(THIS_MODULE, "mt");
323 if (IS_ERR(mtc))
324 return PTR_ERR(mtc);
326 mt_class = mtc;
328 return 0;
331 subsys_initcall(mt_init);