xref: /linux/arch/mips/mm/c-octeon.c (revision bb960a1e42042e82447a5bc0941b3ab6d614bac3)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2005-2007 Cavium Networks
7  */
8 #include <linux/init.h>
9 #include <linux/kernel.h>
10 #include <linux/sched.h>
11 #include <linux/mm.h>
12 #include <linux/bitops.h>
13 #include <linux/cpu.h>
14 #include <linux/io.h>
15 
16 #include <asm/bcache.h>
17 #include <asm/bootinfo.h>
18 #include <asm/cacheops.h>
19 #include <asm/cpu-features.h>
20 #include <asm/page.h>
21 #include <asm/pgtable.h>
22 #include <asm/r4kcache.h>
23 #include <asm/system.h>
24 #include <asm/mmu_context.h>
25 #include <asm/war.h>
26 
27 #include <asm/octeon/octeon.h>
28 
29 unsigned long long cache_err_dcache[NR_CPUS];
30 
31 /**
32  * Octeon automatically flushes the dcache on tlb changes, so
33  * from Linux's viewpoint it acts much like a physically
34  * tagged cache. No flushing is needed
35  *
36  */
37 static void octeon_flush_data_cache_page(unsigned long addr)
38 {
39     /* Nothing to do */
40 }
41 
42 static inline void octeon_local_flush_icache(void)
43 {
44 	asm volatile ("synci 0($0)");
45 }
46 
47 /*
48  * Flush local I-cache for the specified range.
49  */
50 static void local_octeon_flush_icache_range(unsigned long start,
51 					    unsigned long end)
52 {
53 	octeon_local_flush_icache();
54 }
55 
56 /**
57  * Flush caches as necessary for all cores affected by a
58  * vma. If no vma is supplied, all cores are flushed.
59  *
60  * @vma:    VMA to flush or NULL to flush all icaches.
61  */
62 static void octeon_flush_icache_all_cores(struct vm_area_struct *vma)
63 {
64 	extern void octeon_send_ipi_single(int cpu, unsigned int action);
65 #ifdef CONFIG_SMP
66 	int cpu;
67 	cpumask_t mask;
68 #endif
69 
70 	mb();
71 	octeon_local_flush_icache();
72 #ifdef CONFIG_SMP
73 	preempt_disable();
74 	cpu = smp_processor_id();
75 
76 	/*
77 	 * If we have a vma structure, we only need to worry about
78 	 * cores it has been used on
79 	 */
80 	if (vma)
81 		mask = vma->vm_mm->cpu_vm_mask;
82 	else
83 		mask = cpu_online_map;
84 	cpu_clear(cpu, mask);
85 	for_each_cpu_mask(cpu, mask)
86 		octeon_send_ipi_single(cpu, SMP_ICACHE_FLUSH);
87 
88 	preempt_enable();
89 #endif
90 }
91 
92 
93 /**
94  * Called to flush the icache on all cores
95  */
96 static void octeon_flush_icache_all(void)
97 {
98 	octeon_flush_icache_all_cores(NULL);
99 }
100 
101 
102 /**
103  * Called to flush all memory associated with a memory
104  * context.
105  *
106  * @mm:     Memory context to flush
107  */
108 static void octeon_flush_cache_mm(struct mm_struct *mm)
109 {
110 	/*
111 	 * According to the R4K version of this file, CPUs without
112 	 * dcache aliases don't need to do anything here
113 	 */
114 }
115 
116 
117 /**
118  * Flush a range of kernel addresses out of the icache
119  *
120  */
121 static void octeon_flush_icache_range(unsigned long start, unsigned long end)
122 {
123 	octeon_flush_icache_all_cores(NULL);
124 }
125 
126 
127 /**
128  * Flush the icache for a trampoline. These are used for interrupt
129  * and exception hooking.
130  *
131  * @addr:   Address to flush
132  */
133 static void octeon_flush_cache_sigtramp(unsigned long addr)
134 {
135 	struct vm_area_struct *vma;
136 
137 	vma = find_vma(current->mm, addr);
138 	octeon_flush_icache_all_cores(vma);
139 }
140 
141 
142 /**
143  * Flush a range out of a vma
144  *
145  * @vma:    VMA to flush
146  * @start:
147  * @end:
148  */
149 static void octeon_flush_cache_range(struct vm_area_struct *vma,
150 				     unsigned long start, unsigned long end)
151 {
152 	if (vma->vm_flags & VM_EXEC)
153 		octeon_flush_icache_all_cores(vma);
154 }
155 
156 
157 /**
158  * Flush a specific page of a vma
159  *
160  * @vma:    VMA to flush page for
161  * @page:   Page to flush
162  * @pfn:
163  */
164 static void octeon_flush_cache_page(struct vm_area_struct *vma,
165 				    unsigned long page, unsigned long pfn)
166 {
167 	if (vma->vm_flags & VM_EXEC)
168 		octeon_flush_icache_all_cores(vma);
169 }
170 
171 
172 /**
173  * Probe Octeon's caches
174  *
175  */
176 static void __devinit probe_octeon(void)
177 {
178 	unsigned long icache_size;
179 	unsigned long dcache_size;
180 	unsigned int config1;
181 	struct cpuinfo_mips *c = &current_cpu_data;
182 
183 	switch (c->cputype) {
184 	case CPU_CAVIUM_OCTEON:
185 		config1 = read_c0_config1();
186 		c->icache.linesz = 2 << ((config1 >> 19) & 7);
187 		c->icache.sets = 64 << ((config1 >> 22) & 7);
188 		c->icache.ways = 1 + ((config1 >> 16) & 7);
189 		c->icache.flags |= MIPS_CACHE_VTAG;
190 		icache_size =
191 			c->icache.sets * c->icache.ways * c->icache.linesz;
192 		c->icache.waybit = ffs(icache_size / c->icache.ways) - 1;
193 		c->dcache.linesz = 128;
194 		if (OCTEON_IS_MODEL(OCTEON_CN3XXX))
195 			c->dcache.sets = 1; /* CN3XXX has one Dcache set */
196 		else
197 			c->dcache.sets = 2; /* CN5XXX has two Dcache sets */
198 		c->dcache.ways = 64;
199 		dcache_size =
200 			c->dcache.sets * c->dcache.ways * c->dcache.linesz;
201 		c->dcache.waybit = ffs(dcache_size / c->dcache.ways) - 1;
202 		c->options |= MIPS_CPU_PREFETCH;
203 		break;
204 
205 	default:
206 		panic("Unsupported Cavium Networks CPU type\n");
207 		break;
208 	}
209 
210 	/* compute a couple of other cache variables */
211 	c->icache.waysize = icache_size / c->icache.ways;
212 	c->dcache.waysize = dcache_size / c->dcache.ways;
213 
214 	c->icache.sets = icache_size / (c->icache.linesz * c->icache.ways);
215 	c->dcache.sets = dcache_size / (c->dcache.linesz * c->dcache.ways);
216 
217 	if (smp_processor_id() == 0) {
218 		pr_notice("Primary instruction cache %ldkB, %s, %d way, "
219 			  "%d sets, linesize %d bytes.\n",
220 			  icache_size >> 10,
221 			  cpu_has_vtag_icache ?
222 				"virtually tagged" : "physically tagged",
223 			  c->icache.ways, c->icache.sets, c->icache.linesz);
224 
225 		pr_notice("Primary data cache %ldkB, %d-way, %d sets, "
226 			  "linesize %d bytes.\n",
227 			  dcache_size >> 10, c->dcache.ways,
228 			  c->dcache.sets, c->dcache.linesz);
229 	}
230 }
231 
232 
233 /**
234  * Setup the Octeon cache flush routines
235  *
236  */
237 void __devinit octeon_cache_init(void)
238 {
239 	extern unsigned long ebase;
240 	extern char except_vec2_octeon;
241 
242 	memcpy((void *)(ebase + 0x100), &except_vec2_octeon, 0x80);
243 	octeon_flush_cache_sigtramp(ebase + 0x100);
244 
245 	probe_octeon();
246 
247 	shm_align_mask = PAGE_SIZE - 1;
248 
249 	flush_cache_all			= octeon_flush_icache_all;
250 	__flush_cache_all		= octeon_flush_icache_all;
251 	flush_cache_mm			= octeon_flush_cache_mm;
252 	flush_cache_page		= octeon_flush_cache_page;
253 	flush_cache_range		= octeon_flush_cache_range;
254 	flush_cache_sigtramp		= octeon_flush_cache_sigtramp;
255 	flush_icache_all		= octeon_flush_icache_all;
256 	flush_data_cache_page		= octeon_flush_data_cache_page;
257 	flush_icache_range		= octeon_flush_icache_range;
258 	local_flush_icache_range	= local_octeon_flush_icache_range;
259 
260 	build_clear_page();
261 	build_copy_page();
262 }
263 
264 /**
265  * Handle a cache error exception
266  */
267 
268 static void  cache_parity_error_octeon(int non_recoverable)
269 {
270 	unsigned long coreid = cvmx_get_core_num();
271 	uint64_t icache_err = read_octeon_c0_icacheerr();
272 
273 	pr_err("Cache error exception:\n");
274 	pr_err("cp0_errorepc == %lx\n", read_c0_errorepc());
275 	if (icache_err & 1) {
276 		pr_err("CacheErr (Icache) == %llx\n",
277 		       (unsigned long long)icache_err);
278 		write_octeon_c0_icacheerr(0);
279 	}
280 	if (cache_err_dcache[coreid] & 1) {
281 		pr_err("CacheErr (Dcache) == %llx\n",
282 		       (unsigned long long)cache_err_dcache[coreid]);
283 		cache_err_dcache[coreid] = 0;
284 	}
285 
286 	if (non_recoverable)
287 		panic("Can't handle cache error: nested exception");
288 }
289 
290 /**
291  * Called when the the exception is not recoverable
292  */
293 
294 asmlinkage void cache_parity_error_octeon_recoverable(void)
295 {
296 	cache_parity_error_octeon(0);
297 }
298 
299 /**
300  * Called when the the exception is recoverable
301  */
302 
303 asmlinkage void cache_parity_error_octeon_non_recoverable(void)
304 {
305 	cache_parity_error_octeon(1);
306 }
307 
308