xref: /linux/arch/parisc/kernel/cache.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
1 /* $Id: cache.c,v 1.4 2000/01/25 00:11:38 prumpf Exp $
2  *
3  * This file is subject to the terms and conditions of the GNU General Public
4  * License.  See the file "COPYING" in the main directory of this archive
5  * for more details.
6  *
7  * Copyright (C) 1999-2006 Helge Deller <deller@gmx.de> (07-13-1999)
8  * Copyright (C) 1999 SuSE GmbH Nuernberg
9  * Copyright (C) 2000 Philipp Rumpf (prumpf@tux.org)
10  *
11  * Cache and TLB management
12  *
13  */
14 
15 #include <linux/init.h>
16 #include <linux/kernel.h>
17 #include <linux/mm.h>
18 #include <linux/module.h>
19 #include <linux/seq_file.h>
20 #include <linux/pagemap.h>
21 
22 #include <asm/pdc.h>
23 #include <asm/cache.h>
24 #include <asm/cacheflush.h>
25 #include <asm/tlbflush.h>
26 #include <asm/system.h>
27 #include <asm/page.h>
28 #include <asm/pgalloc.h>
29 #include <asm/processor.h>
30 #include <asm/sections.h>
31 
32 int split_tlb __read_mostly;
33 int dcache_stride __read_mostly;
34 int icache_stride __read_mostly;
35 EXPORT_SYMBOL(dcache_stride);
36 
37 
38 #if defined(CONFIG_SMP)
39 /* On some machines (e.g. ones with the Merced bus), there can be
40  * only a single PxTLB broadcast at a time; this must be guaranteed
41  * by software.  We put a spinlock around all TLB flushes  to
42  * ensure this.
43  */
44 DEFINE_SPINLOCK(pa_tlb_lock);
45 EXPORT_SYMBOL(pa_tlb_lock);
46 #endif
47 
48 struct pdc_cache_info cache_info __read_mostly;
49 #ifndef CONFIG_PA20
50 static struct pdc_btlb_info btlb_info __read_mostly;
51 #endif
52 
53 #ifdef CONFIG_SMP
54 void
55 flush_data_cache(void)
56 {
57 	on_each_cpu(flush_data_cache_local, NULL, 1, 1);
58 }
59 void
60 flush_instruction_cache(void)
61 {
62 	on_each_cpu(flush_instruction_cache_local, NULL, 1, 1);
63 }
64 #endif
65 
66 void
67 flush_cache_all_local(void)
68 {
69 	flush_instruction_cache_local(NULL);
70 	flush_data_cache_local(NULL);
71 }
72 EXPORT_SYMBOL(flush_cache_all_local);
73 
74 /* flushes EVERYTHING (tlb & cache) */
75 
76 void
77 flush_all_caches(void)
78 {
79 	flush_cache_all();
80 	flush_tlb_all();
81 }
82 EXPORT_SYMBOL(flush_all_caches);
83 
84 void
85 update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t pte)
86 {
87 	struct page *page = pte_page(pte);
88 
89 	if (pfn_valid(page_to_pfn(page)) && page_mapping(page) &&
90 	    test_bit(PG_dcache_dirty, &page->flags)) {
91 
92 		flush_kernel_dcache_page(page);
93 		clear_bit(PG_dcache_dirty, &page->flags);
94 	}
95 }
96 
97 void
98 show_cache_info(struct seq_file *m)
99 {
100 	char buf[32];
101 
102 	seq_printf(m, "I-cache\t\t: %ld KB\n",
103 		cache_info.ic_size/1024 );
104 	if (cache_info.dc_loop == 1)
105 		snprintf(buf, 32, "%lu-way associative", cache_info.dc_loop);
106 	seq_printf(m, "D-cache\t\t: %ld KB (%s%s, %s)\n",
107 		cache_info.dc_size/1024,
108 		(cache_info.dc_conf.cc_wt ? "WT":"WB"),
109 		(cache_info.dc_conf.cc_sh ? ", shared I/D":""),
110 		((cache_info.dc_loop == 1) ? "direct mapped" : buf));
111 	seq_printf(m, "ITLB entries\t: %ld\n" "DTLB entries\t: %ld%s\n",
112 		cache_info.it_size,
113 		cache_info.dt_size,
114 		cache_info.dt_conf.tc_sh ? " - shared with ITLB":""
115 	);
116 
117 #ifndef CONFIG_PA20
118 	/* BTLB - Block TLB */
119 	if (btlb_info.max_size==0) {
120 		seq_printf(m, "BTLB\t\t: not supported\n" );
121 	} else {
122 		seq_printf(m,
123 		"BTLB fixed\t: max. %d pages, pagesize=%d (%dMB)\n"
124 		"BTLB fix-entr.\t: %d instruction, %d data (%d combined)\n"
125 		"BTLB var-entr.\t: %d instruction, %d data (%d combined)\n",
126 		btlb_info.max_size, (int)4096,
127 		btlb_info.max_size>>8,
128 		btlb_info.fixed_range_info.num_i,
129 		btlb_info.fixed_range_info.num_d,
130 		btlb_info.fixed_range_info.num_comb,
131 		btlb_info.variable_range_info.num_i,
132 		btlb_info.variable_range_info.num_d,
133 		btlb_info.variable_range_info.num_comb
134 		);
135 	}
136 #endif
137 }
138 
139 void __init
140 parisc_cache_init(void)
141 {
142 	if (pdc_cache_info(&cache_info) < 0)
143 		panic("parisc_cache_init: pdc_cache_info failed");
144 
145 #if 0
146 	printk("ic_size %lx dc_size %lx it_size %lx\n",
147 		cache_info.ic_size,
148 		cache_info.dc_size,
149 		cache_info.it_size);
150 
151 	printk("DC  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx\n",
152 		cache_info.dc_base,
153 		cache_info.dc_stride,
154 		cache_info.dc_count,
155 		cache_info.dc_loop);
156 
157 	printk("dc_conf = 0x%lx  alias %d blk %d line %d shift %d\n",
158 		*(unsigned long *) (&cache_info.dc_conf),
159 		cache_info.dc_conf.cc_alias,
160 		cache_info.dc_conf.cc_block,
161 		cache_info.dc_conf.cc_line,
162 		cache_info.dc_conf.cc_shift);
163 	printk("	wt %d sh %d cst %d hv %d\n",
164 		cache_info.dc_conf.cc_wt,
165 		cache_info.dc_conf.cc_sh,
166 		cache_info.dc_conf.cc_cst,
167 		cache_info.dc_conf.cc_hv);
168 
169 	printk("IC  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx\n",
170 		cache_info.ic_base,
171 		cache_info.ic_stride,
172 		cache_info.ic_count,
173 		cache_info.ic_loop);
174 
175 	printk("ic_conf = 0x%lx  alias %d blk %d line %d shift %d\n",
176 		*(unsigned long *) (&cache_info.ic_conf),
177 		cache_info.ic_conf.cc_alias,
178 		cache_info.ic_conf.cc_block,
179 		cache_info.ic_conf.cc_line,
180 		cache_info.ic_conf.cc_shift);
181 	printk("	wt %d sh %d cst %d hv %d\n",
182 		cache_info.ic_conf.cc_wt,
183 		cache_info.ic_conf.cc_sh,
184 		cache_info.ic_conf.cc_cst,
185 		cache_info.ic_conf.cc_hv);
186 
187 	printk("D-TLB conf: sh %d page %d cst %d aid %d pad1 %d \n",
188 		cache_info.dt_conf.tc_sh,
189 		cache_info.dt_conf.tc_page,
190 		cache_info.dt_conf.tc_cst,
191 		cache_info.dt_conf.tc_aid,
192 		cache_info.dt_conf.tc_pad1);
193 
194 	printk("I-TLB conf: sh %d page %d cst %d aid %d pad1 %d \n",
195 		cache_info.it_conf.tc_sh,
196 		cache_info.it_conf.tc_page,
197 		cache_info.it_conf.tc_cst,
198 		cache_info.it_conf.tc_aid,
199 		cache_info.it_conf.tc_pad1);
200 #endif
201 
202 	split_tlb = 0;
203 	if (cache_info.dt_conf.tc_sh == 0 || cache_info.dt_conf.tc_sh == 2) {
204 		if (cache_info.dt_conf.tc_sh == 2)
205 			printk(KERN_WARNING "Unexpected TLB configuration. "
206 			"Will flush I/D separately (could be optimized).\n");
207 
208 		split_tlb = 1;
209 	}
210 
211 	/* "New and Improved" version from Jim Hull
212 	 *	(1 << (cc_block-1)) * (cc_line << (4 + cnf.cc_shift))
213 	 * The following CAFL_STRIDE is an optimized version, see
214 	 * http://lists.parisc-linux.org/pipermail/parisc-linux/2004-June/023625.html
215 	 * http://lists.parisc-linux.org/pipermail/parisc-linux/2004-June/023671.html
216 	 */
217 #define CAFL_STRIDE(cnf) (cnf.cc_line << (3 + cnf.cc_block + cnf.cc_shift))
218 	dcache_stride = CAFL_STRIDE(cache_info.dc_conf);
219 	icache_stride = CAFL_STRIDE(cache_info.ic_conf);
220 #undef CAFL_STRIDE
221 
222 #ifndef CONFIG_PA20
223 	if (pdc_btlb_info(&btlb_info) < 0) {
224 		memset(&btlb_info, 0, sizeof btlb_info);
225 	}
226 #endif
227 
228 	if ((boot_cpu_data.pdc.capabilities & PDC_MODEL_NVA_MASK) ==
229 						PDC_MODEL_NVA_UNSUPPORTED) {
230 		printk(KERN_WARNING "parisc_cache_init: Only equivalent aliasing supported!\n");
231 #if 0
232 		panic("SMP kernel required to avoid non-equivalent aliasing");
233 #endif
234 	}
235 }
236 
237 void disable_sr_hashing(void)
238 {
239 	int srhash_type, retval;
240 	unsigned long space_bits;
241 
242 	switch (boot_cpu_data.cpu_type) {
243 	case pcx: /* We shouldn't get this far.  setup.c should prevent it. */
244 		BUG();
245 		return;
246 
247 	case pcxs:
248 	case pcxt:
249 	case pcxt_:
250 		srhash_type = SRHASH_PCXST;
251 		break;
252 
253 	case pcxl:
254 		srhash_type = SRHASH_PCXL;
255 		break;
256 
257 	case pcxl2: /* pcxl2 doesn't support space register hashing */
258 		return;
259 
260 	default: /* Currently all PA2.0 machines use the same ins. sequence */
261 		srhash_type = SRHASH_PA20;
262 		break;
263 	}
264 
265 	disable_sr_hashing_asm(srhash_type);
266 
267 	retval = pdc_spaceid_bits(&space_bits);
268 	/* If this procedure isn't implemented, don't panic. */
269 	if (retval < 0 && retval != PDC_BAD_OPTION)
270 		panic("pdc_spaceid_bits call failed.\n");
271 	if (space_bits != 0)
272 		panic("SpaceID hashing is still on!\n");
273 }
274 
275 void flush_dcache_page(struct page *page)
276 {
277 	struct address_space *mapping = page_mapping(page);
278 	struct vm_area_struct *mpnt;
279 	struct prio_tree_iter iter;
280 	unsigned long offset;
281 	unsigned long addr;
282 	pgoff_t pgoff;
283 	unsigned long pfn = page_to_pfn(page);
284 
285 
286 	if (mapping && !mapping_mapped(mapping)) {
287 		set_bit(PG_dcache_dirty, &page->flags);
288 		return;
289 	}
290 
291 	flush_kernel_dcache_page(page);
292 
293 	if (!mapping)
294 		return;
295 
296 	pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
297 
298 	/* We have carefully arranged in arch_get_unmapped_area() that
299 	 * *any* mappings of a file are always congruently mapped (whether
300 	 * declared as MAP_PRIVATE or MAP_SHARED), so we only need
301 	 * to flush one address here for them all to become coherent */
302 
303 	flush_dcache_mmap_lock(mapping);
304 	vma_prio_tree_foreach(mpnt, &iter, &mapping->i_mmap, pgoff, pgoff) {
305 		offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
306 		addr = mpnt->vm_start + offset;
307 
308 		/* Flush instructions produce non access tlb misses.
309 		 * On PA, we nullify these instructions rather than
310 		 * taking a page fault if the pte doesn't exist.
311 		 * This is just for speed.  If the page translation
312 		 * isn't there, there's no point exciting the
313 		 * nadtlb handler into a nullification frenzy.
314 		 *
315 		 * Make sure we really have this page: the private
316 		 * mappings may cover this area but have COW'd this
317 		 * particular page.
318 		 */
319   		if (translation_exists(mpnt, addr, pfn)) {
320 			__flush_cache_page(mpnt, addr);
321 			break;
322 		}
323 	}
324 	flush_dcache_mmap_unlock(mapping);
325 }
326 EXPORT_SYMBOL(flush_dcache_page);
327 
328 /* Defined in arch/parisc/kernel/pacache.S */
329 EXPORT_SYMBOL(flush_kernel_dcache_range_asm);
330 EXPORT_SYMBOL(flush_kernel_dcache_page_asm);
331 EXPORT_SYMBOL(flush_data_cache_local);
332 EXPORT_SYMBOL(flush_kernel_icache_range_asm);
333 
334 void clear_user_page_asm(void *page, unsigned long vaddr)
335 {
336 	/* This function is implemented in assembly in pacache.S */
337 	extern void __clear_user_page_asm(void *page, unsigned long vaddr);
338 
339 	purge_tlb_start();
340 	__clear_user_page_asm(page, vaddr);
341 	purge_tlb_end();
342 }
343 
344 #define FLUSH_THRESHOLD 0x80000 /* 0.5MB */
345 int parisc_cache_flush_threshold __read_mostly = FLUSH_THRESHOLD;
346 
347 void parisc_setup_cache_timing(void)
348 {
349 	unsigned long rangetime, alltime;
350 	unsigned long size;
351 
352 	alltime = mfctl(16);
353 	flush_data_cache();
354 	alltime = mfctl(16) - alltime;
355 
356 	size = (unsigned long)(_end - _text);
357 	rangetime = mfctl(16);
358 	flush_kernel_dcache_range((unsigned long)_text, size);
359 	rangetime = mfctl(16) - rangetime;
360 
361 	printk(KERN_DEBUG "Whole cache flush %lu cycles, flushing %lu bytes %lu cycles\n",
362 		alltime, size, rangetime);
363 
364 	/* Racy, but if we see an intermediate value, it's ok too... */
365 	parisc_cache_flush_threshold = size * alltime / rangetime;
366 
367 	parisc_cache_flush_threshold = (parisc_cache_flush_threshold + L1_CACHE_BYTES - 1) &~ (L1_CACHE_BYTES - 1);
368 	if (!parisc_cache_flush_threshold)
369 		parisc_cache_flush_threshold = FLUSH_THRESHOLD;
370 
371 	printk(KERN_INFO "Setting cache flush threshold to %x (%d CPUs online)\n", parisc_cache_flush_threshold, num_online_cpus());
372 }
373