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) 1999-2006 Helge Deller <deller@gmx.de> (07-13-1999)
7 * Copyright (C) 1999 SuSE GmbH Nuernberg
8 * Copyright (C) 2000 Philipp Rumpf (prumpf@tux.org)
9 *
10 * Cache and TLB management
11 *
12 */
13
14#include <linux/init.h>
15#include <linux/kernel.h>
16#include <linux/mm.h>
17#include <linux/module.h>
18#include <linux/seq_file.h>
19#include <linux/pagemap.h>
20#include <linux/sched.h>
21#include <asm/pdc.h>
22#include <asm/cache.h>
23#include <asm/cacheflush.h>
24#include <asm/tlbflush.h>
25#include <asm/page.h>
26#include <asm/pgalloc.h>
27#include <asm/processor.h>
28#include <asm/sections.h>
29#include <asm/shmparam.h>
30
31int split_tlb __read_mostly;
32int dcache_stride __read_mostly;
33int icache_stride __read_mostly;
34EXPORT_SYMBOL(dcache_stride);
35
36void flush_dcache_page_asm(unsigned long phys_addr, unsigned long vaddr);
37EXPORT_SYMBOL(flush_dcache_page_asm);
38void flush_icache_page_asm(unsigned long phys_addr, unsigned long vaddr);
39
40
41/* On some machines (e.g. ones with the Merced bus), there can be
42 * only a single PxTLB broadcast at a time; this must be guaranteed
43 * by software.  We put a spinlock around all TLB flushes  to
44 * ensure this.
45 */
46DEFINE_SPINLOCK(pa_tlb_lock);
47
48struct pdc_cache_info cache_info __read_mostly;
49#ifndef CONFIG_PA20
50static struct pdc_btlb_info btlb_info __read_mostly;
51#endif
52
53#ifdef CONFIG_SMP
54void
55flush_data_cache(void)
56{
57	on_each_cpu(flush_data_cache_local, NULL, 1);
58}
59void
60flush_instruction_cache(void)
61{
62	on_each_cpu(flush_instruction_cache_local, NULL, 1);
63}
64#endif
65
66void
67flush_cache_all_local(void)
68{
69	flush_instruction_cache_local(NULL);
70	flush_data_cache_local(NULL);
71}
72EXPORT_SYMBOL(flush_cache_all_local);
73
74/* Virtual address of pfn.  */
75#define pfn_va(pfn)	__va(PFN_PHYS(pfn))
76
77void
78update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
79{
80	unsigned long pfn = pte_pfn(*ptep);
81	struct page *page;
82
83	/* We don't have pte special.  As a result, we can be called with
84	   an invalid pfn and we don't need to flush the kernel dcache page.
85	   This occurs with FireGL card in C8000.  */
86	if (!pfn_valid(pfn))
87		return;
88
89	page = pfn_to_page(pfn);
90	if (page_mapping(page) && test_bit(PG_dcache_dirty, &page->flags)) {
91		flush_kernel_dcache_page_addr(pfn_va(pfn));
92		clear_bit(PG_dcache_dirty, &page->flags);
93	} else if (parisc_requires_coherency())
94		flush_kernel_dcache_page_addr(pfn_va(pfn));
95}
96
97void
98show_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
139void __init
140parisc_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
237void 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
275static inline void
276__flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
277		   unsigned long physaddr)
278{
279	preempt_disable();
280	flush_dcache_page_asm(physaddr, vmaddr);
281	if (vma->vm_flags & VM_EXEC)
282		flush_icache_page_asm(physaddr, vmaddr);
283	preempt_enable();
284}
285
286void flush_dcache_page(struct page *page)
287{
288	struct address_space *mapping = page_mapping(page);
289	struct vm_area_struct *mpnt;
290	unsigned long offset;
291	unsigned long addr, old_addr = 0;
292	pgoff_t pgoff;
293
294	if (mapping && !mapping_mapped(mapping)) {
295		set_bit(PG_dcache_dirty, &page->flags);
296		return;
297	}
298
299	flush_kernel_dcache_page(page);
300
301	if (!mapping)
302		return;
303
304	pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
305
306	/* We have carefully arranged in arch_get_unmapped_area() that
307	 * *any* mappings of a file are always congruently mapped (whether
308	 * declared as MAP_PRIVATE or MAP_SHARED), so we only need
309	 * to flush one address here for them all to become coherent */
310
311	flush_dcache_mmap_lock(mapping);
312	vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
313		offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
314		addr = mpnt->vm_start + offset;
315
316		/* The TLB is the engine of coherence on parisc: The
317		 * CPU is entitled to speculate any page with a TLB
318		 * mapping, so here we kill the mapping then flush the
319		 * page along a special flush only alias mapping.
320		 * This guarantees that the page is no-longer in the
321		 * cache for any process and nor may it be
322		 * speculatively read in (until the user or kernel
323		 * specifically accesses it, of course) */
324
325		flush_tlb_page(mpnt, addr);
326		if (old_addr == 0 || (old_addr & (SHM_COLOUR - 1))
327				      != (addr & (SHM_COLOUR - 1))) {
328			__flush_cache_page(mpnt, addr, page_to_phys(page));
329			if (old_addr)
330				printk(KERN_ERR "INEQUIVALENT ALIASES 0x%lx and 0x%lx in file %s\n", old_addr, addr, mpnt->vm_file ? (char *)mpnt->vm_file->f_path.dentry->d_name.name : "(null)");
331			old_addr = addr;
332		}
333	}
334	flush_dcache_mmap_unlock(mapping);
335}
336EXPORT_SYMBOL(flush_dcache_page);
337
338/* Defined in arch/parisc/kernel/pacache.S */
339EXPORT_SYMBOL(flush_kernel_dcache_range_asm);
340EXPORT_SYMBOL(flush_kernel_dcache_page_asm);
341EXPORT_SYMBOL(flush_data_cache_local);
342EXPORT_SYMBOL(flush_kernel_icache_range_asm);
343
344#define FLUSH_THRESHOLD 0x80000 /* 0.5MB */
345static unsigned long parisc_cache_flush_threshold __read_mostly = FLUSH_THRESHOLD;
346
347#define FLUSH_TLB_THRESHOLD (2*1024*1024) /* 2MB initial TLB threshold */
348static unsigned long parisc_tlb_flush_threshold __read_mostly = FLUSH_TLB_THRESHOLD;
349
350void __init parisc_setup_cache_timing(void)
351{
352	unsigned long rangetime, alltime;
353	unsigned long size, start;
354
355	alltime = mfctl(16);
356	flush_data_cache();
357	alltime = mfctl(16) - alltime;
358
359	size = (unsigned long)(_end - _text);
360	rangetime = mfctl(16);
361	flush_kernel_dcache_range((unsigned long)_text, size);
362	rangetime = mfctl(16) - rangetime;
363
364	printk(KERN_DEBUG "Whole cache flush %lu cycles, flushing %lu bytes %lu cycles\n",
365		alltime, size, rangetime);
366
367	/* Racy, but if we see an intermediate value, it's ok too... */
368	parisc_cache_flush_threshold = size * alltime / rangetime;
369
370	parisc_cache_flush_threshold = L1_CACHE_ALIGN(parisc_cache_flush_threshold);
371	if (!parisc_cache_flush_threshold)
372		parisc_cache_flush_threshold = FLUSH_THRESHOLD;
373
374	if (parisc_cache_flush_threshold > cache_info.dc_size)
375		parisc_cache_flush_threshold = cache_info.dc_size;
376
377	printk(KERN_INFO "Setting cache flush threshold to %lu kB\n",
378		parisc_cache_flush_threshold/1024);
379
380	/* calculate TLB flush threshold */
381
382	alltime = mfctl(16);
383	flush_tlb_all();
384	alltime = mfctl(16) - alltime;
385
386	size = PAGE_SIZE;
387	start = (unsigned long) _text;
388	rangetime = mfctl(16);
389	while (start < (unsigned long) _end) {
390		flush_tlb_kernel_range(start, start + PAGE_SIZE);
391		start += PAGE_SIZE;
392		size += PAGE_SIZE;
393	}
394	rangetime = mfctl(16) - rangetime;
395
396	printk(KERN_DEBUG "Whole TLB flush %lu cycles, flushing %lu bytes %lu cycles\n",
397		alltime, size, rangetime);
398
399	parisc_tlb_flush_threshold = size * alltime / rangetime;
400	parisc_tlb_flush_threshold *= num_online_cpus();
401	parisc_tlb_flush_threshold = PAGE_ALIGN(parisc_tlb_flush_threshold);
402	if (!parisc_tlb_flush_threshold)
403		parisc_tlb_flush_threshold = FLUSH_TLB_THRESHOLD;
404
405	printk(KERN_INFO "Setting TLB flush threshold to %lu kB\n",
406		parisc_tlb_flush_threshold/1024);
407}
408
409extern void purge_kernel_dcache_page_asm(unsigned long);
410extern void clear_user_page_asm(void *, unsigned long);
411extern void copy_user_page_asm(void *, void *, unsigned long);
412
413void flush_kernel_dcache_page_addr(void *addr)
414{
415	unsigned long flags;
416
417	flush_kernel_dcache_page_asm(addr);
418	purge_tlb_start(flags);
419	pdtlb_kernel(addr);
420	purge_tlb_end(flags);
421}
422EXPORT_SYMBOL(flush_kernel_dcache_page_addr);
423
424void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
425	struct page *pg)
426{
427       /* Copy using kernel mapping.  No coherency is needed (all in
428	  kunmap) for the `to' page.  However, the `from' page needs to
429	  be flushed through a mapping equivalent to the user mapping
430	  before it can be accessed through the kernel mapping. */
431	preempt_disable();
432	flush_dcache_page_asm(__pa(vfrom), vaddr);
433	preempt_enable();
434	copy_page_asm(vto, vfrom);
435}
436EXPORT_SYMBOL(copy_user_page);
437
438/* __flush_tlb_range()
439 *
440 * returns 1 if all TLBs were flushed.
441 */
442int __flush_tlb_range(unsigned long sid, unsigned long start,
443		      unsigned long end)
444{
445	unsigned long flags, size;
446
447	size = (end - start);
448	if (size >= parisc_tlb_flush_threshold) {
449		flush_tlb_all();
450		return 1;
451	}
452
453	/* Purge TLB entries for small ranges using the pdtlb and
454	   pitlb instructions.  These instructions execute locally
455	   but cause a purge request to be broadcast to other TLBs.  */
456	if (likely(!split_tlb)) {
457		while (start < end) {
458			purge_tlb_start(flags);
459			mtsp(sid, 1);
460			pdtlb(start);
461			purge_tlb_end(flags);
462			start += PAGE_SIZE;
463		}
464		return 0;
465	}
466
467	/* split TLB case */
468	while (start < end) {
469		purge_tlb_start(flags);
470		mtsp(sid, 1);
471		pdtlb(start);
472		pitlb(start);
473		purge_tlb_end(flags);
474		start += PAGE_SIZE;
475	}
476	return 0;
477}
478
479static void cacheflush_h_tmp_function(void *dummy)
480{
481	flush_cache_all_local();
482}
483
484void flush_cache_all(void)
485{
486	on_each_cpu(cacheflush_h_tmp_function, NULL, 1);
487}
488
489static inline unsigned long mm_total_size(struct mm_struct *mm)
490{
491	struct vm_area_struct *vma;
492	unsigned long usize = 0;
493
494	for (vma = mm->mmap; vma; vma = vma->vm_next)
495		usize += vma->vm_end - vma->vm_start;
496	return usize;
497}
498
499static inline pte_t *get_ptep(pgd_t *pgd, unsigned long addr)
500{
501	pte_t *ptep = NULL;
502
503	if (!pgd_none(*pgd)) {
504		pud_t *pud = pud_offset(pgd, addr);
505		if (!pud_none(*pud)) {
506			pmd_t *pmd = pmd_offset(pud, addr);
507			if (!pmd_none(*pmd))
508				ptep = pte_offset_map(pmd, addr);
509		}
510	}
511	return ptep;
512}
513
514void flush_cache_mm(struct mm_struct *mm)
515{
516	struct vm_area_struct *vma;
517	pgd_t *pgd;
518
519	/* Flushing the whole cache on each cpu takes forever on
520	   rp3440, etc.  So, avoid it if the mm isn't too big.  */
521	if (mm_total_size(mm) >= parisc_cache_flush_threshold) {
522		flush_cache_all();
523		return;
524	}
525
526	if (mm->context == mfsp(3)) {
527		for (vma = mm->mmap; vma; vma = vma->vm_next) {
528			flush_user_dcache_range_asm(vma->vm_start, vma->vm_end);
529			if ((vma->vm_flags & VM_EXEC) == 0)
530				continue;
531			flush_user_icache_range_asm(vma->vm_start, vma->vm_end);
532		}
533		return;
534	}
535
536	pgd = mm->pgd;
537	for (vma = mm->mmap; vma; vma = vma->vm_next) {
538		unsigned long addr;
539
540		for (addr = vma->vm_start; addr < vma->vm_end;
541		     addr += PAGE_SIZE) {
542			unsigned long pfn;
543			pte_t *ptep = get_ptep(pgd, addr);
544			if (!ptep)
545				continue;
546			pfn = pte_pfn(*ptep);
547			if (!pfn_valid(pfn))
548				continue;
549			__flush_cache_page(vma, addr, PFN_PHYS(pfn));
550		}
551	}
552}
553
554void
555flush_user_dcache_range(unsigned long start, unsigned long end)
556{
557	if ((end - start) < parisc_cache_flush_threshold)
558		flush_user_dcache_range_asm(start,end);
559	else
560		flush_data_cache();
561}
562
563void
564flush_user_icache_range(unsigned long start, unsigned long end)
565{
566	if ((end - start) < parisc_cache_flush_threshold)
567		flush_user_icache_range_asm(start,end);
568	else
569		flush_instruction_cache();
570}
571
572void flush_cache_range(struct vm_area_struct *vma,
573		unsigned long start, unsigned long end)
574{
575	unsigned long addr;
576	pgd_t *pgd;
577
578	BUG_ON(!vma->vm_mm->context);
579
580	if ((end - start) >= parisc_cache_flush_threshold) {
581		flush_cache_all();
582		return;
583	}
584
585	if (vma->vm_mm->context == mfsp(3)) {
586		flush_user_dcache_range_asm(start, end);
587		if (vma->vm_flags & VM_EXEC)
588			flush_user_icache_range_asm(start, end);
589		return;
590	}
591
592	pgd = vma->vm_mm->pgd;
593	for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
594		unsigned long pfn;
595		pte_t *ptep = get_ptep(pgd, addr);
596		if (!ptep)
597			continue;
598		pfn = pte_pfn(*ptep);
599		if (pfn_valid(pfn))
600			__flush_cache_page(vma, addr, PFN_PHYS(pfn));
601	}
602}
603
604void
605flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned long pfn)
606{
607	BUG_ON(!vma->vm_mm->context);
608
609	if (pfn_valid(pfn)) {
610		flush_tlb_page(vma, vmaddr);
611		__flush_cache_page(vma, vmaddr, PFN_PHYS(pfn));
612	}
613}
614