xref: /openbmc/linux/arch/sparc/mm/leon_mm.c (revision 827634ad)
1 /*
2  *  linux/arch/sparc/mm/leon_m.c
3  *
4  * Copyright (C) 2004 Konrad Eisele (eiselekd@web.de, konrad@gaisler.com) Gaisler Research
5  * Copyright (C) 2009 Daniel Hellstrom (daniel@gaisler.com) Aeroflex Gaisler AB
6  * Copyright (C) 2009 Konrad Eisele (konrad@gaisler.com) Aeroflex Gaisler AB
7  *
8  * do srmmu probe in software
9  *
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/mm.h>
14 #include <asm/asi.h>
15 #include <asm/leon.h>
16 #include <asm/tlbflush.h>
17 
18 #include "mm_32.h"
19 
20 int leon_flush_during_switch = 1;
21 static int srmmu_swprobe_trace;
22 
23 static inline unsigned long leon_get_ctable_ptr(void)
24 {
25 	unsigned int retval;
26 
27 	__asm__ __volatile__("lda [%1] %2, %0\n\t" :
28 			     "=r" (retval) :
29 			     "r" (SRMMU_CTXTBL_PTR),
30 			     "i" (ASI_LEON_MMUREGS));
31 	return (retval & SRMMU_CTX_PMASK) << 4;
32 }
33 
34 
35 unsigned long leon_swprobe(unsigned long vaddr, unsigned long *paddr)
36 {
37 
38 	unsigned int ctxtbl;
39 	unsigned int pgd, pmd, ped;
40 	unsigned int ptr;
41 	unsigned int lvl, pte, paddrbase;
42 	unsigned int ctx;
43 	unsigned int paddr_calc;
44 
45 	paddrbase = 0;
46 
47 	if (srmmu_swprobe_trace)
48 		printk(KERN_INFO "swprobe: trace on\n");
49 
50 	ctxtbl = leon_get_ctable_ptr();
51 	if (!(ctxtbl)) {
52 		if (srmmu_swprobe_trace)
53 			printk(KERN_INFO "swprobe: leon_get_ctable_ptr returned 0=>0\n");
54 		return 0;
55 	}
56 	if (!_pfn_valid(PFN(ctxtbl))) {
57 		if (srmmu_swprobe_trace)
58 			printk(KERN_INFO
59 			       "swprobe: !_pfn_valid(%x)=>0\n",
60 			       PFN(ctxtbl));
61 		return 0;
62 	}
63 
64 	ctx = srmmu_get_context();
65 	if (srmmu_swprobe_trace)
66 		printk(KERN_INFO "swprobe:  --- ctx (%x) ---\n", ctx);
67 
68 	pgd = LEON_BYPASS_LOAD_PA(ctxtbl + (ctx * 4));
69 
70 	if (((pgd & SRMMU_ET_MASK) == SRMMU_ET_PTE)) {
71 		if (srmmu_swprobe_trace)
72 			printk(KERN_INFO "swprobe: pgd is entry level 3\n");
73 		lvl = 3;
74 		pte = pgd;
75 		paddrbase = pgd & _SRMMU_PTE_PMASK_LEON;
76 		goto ready;
77 	}
78 	if (((pgd & SRMMU_ET_MASK) != SRMMU_ET_PTD)) {
79 		if (srmmu_swprobe_trace)
80 			printk(KERN_INFO "swprobe: pgd is invalid => 0\n");
81 		return 0;
82 	}
83 
84 	if (srmmu_swprobe_trace)
85 		printk(KERN_INFO "swprobe:  --- pgd (%x) ---\n", pgd);
86 
87 	ptr = (pgd & SRMMU_PTD_PMASK) << 4;
88 	ptr += ((((vaddr) >> LEON_PGD_SH) & LEON_PGD_M) * 4);
89 	if (!_pfn_valid(PFN(ptr)))
90 		return 0;
91 
92 	pmd = LEON_BYPASS_LOAD_PA(ptr);
93 	if (((pmd & SRMMU_ET_MASK) == SRMMU_ET_PTE)) {
94 		if (srmmu_swprobe_trace)
95 			printk(KERN_INFO "swprobe: pmd is entry level 2\n");
96 		lvl = 2;
97 		pte = pmd;
98 		paddrbase = pmd & _SRMMU_PTE_PMASK_LEON;
99 		goto ready;
100 	}
101 	if (((pmd & SRMMU_ET_MASK) != SRMMU_ET_PTD)) {
102 		if (srmmu_swprobe_trace)
103 			printk(KERN_INFO "swprobe: pmd is invalid => 0\n");
104 		return 0;
105 	}
106 
107 	if (srmmu_swprobe_trace)
108 		printk(KERN_INFO "swprobe:  --- pmd (%x) ---\n", pmd);
109 
110 	ptr = (pmd & SRMMU_PTD_PMASK) << 4;
111 	ptr += (((vaddr >> LEON_PMD_SH) & LEON_PMD_M) * 4);
112 	if (!_pfn_valid(PFN(ptr))) {
113 		if (srmmu_swprobe_trace)
114 			printk(KERN_INFO "swprobe: !_pfn_valid(%x)=>0\n",
115 			       PFN(ptr));
116 		return 0;
117 	}
118 
119 	ped = LEON_BYPASS_LOAD_PA(ptr);
120 
121 	if (((ped & SRMMU_ET_MASK) == SRMMU_ET_PTE)) {
122 		if (srmmu_swprobe_trace)
123 			printk(KERN_INFO "swprobe: ped is entry level 1\n");
124 		lvl = 1;
125 		pte = ped;
126 		paddrbase = ped & _SRMMU_PTE_PMASK_LEON;
127 		goto ready;
128 	}
129 	if (((ped & SRMMU_ET_MASK) != SRMMU_ET_PTD)) {
130 		if (srmmu_swprobe_trace)
131 			printk(KERN_INFO "swprobe: ped is invalid => 0\n");
132 		return 0;
133 	}
134 
135 	if (srmmu_swprobe_trace)
136 		printk(KERN_INFO "swprobe:  --- ped (%x) ---\n", ped);
137 
138 	ptr = (ped & SRMMU_PTD_PMASK) << 4;
139 	ptr += (((vaddr >> LEON_PTE_SH) & LEON_PTE_M) * 4);
140 	if (!_pfn_valid(PFN(ptr)))
141 		return 0;
142 
143 	ptr = LEON_BYPASS_LOAD_PA(ptr);
144 	if (((ptr & SRMMU_ET_MASK) == SRMMU_ET_PTE)) {
145 		if (srmmu_swprobe_trace)
146 			printk(KERN_INFO "swprobe: ptr is entry level 0\n");
147 		lvl = 0;
148 		pte = ptr;
149 		paddrbase = ptr & _SRMMU_PTE_PMASK_LEON;
150 		goto ready;
151 	}
152 	if (srmmu_swprobe_trace)
153 		printk(KERN_INFO "swprobe: ptr is invalid => 0\n");
154 	return 0;
155 
156 ready:
157 	switch (lvl) {
158 	case 0:
159 		paddr_calc =
160 		    (vaddr & ~(-1 << LEON_PTE_SH)) | ((pte & ~0xff) << 4);
161 		break;
162 	case 1:
163 		paddr_calc =
164 		    (vaddr & ~(-1 << LEON_PMD_SH)) | ((pte & ~0xff) << 4);
165 		break;
166 	case 2:
167 		paddr_calc =
168 		    (vaddr & ~(-1 << LEON_PGD_SH)) | ((pte & ~0xff) << 4);
169 		break;
170 	default:
171 	case 3:
172 		paddr_calc = vaddr;
173 		break;
174 	}
175 	if (srmmu_swprobe_trace)
176 		printk(KERN_INFO "swprobe: padde %x\n", paddr_calc);
177 	if (paddr)
178 		*paddr = paddr_calc;
179 	return pte;
180 }
181 
182 void leon_flush_icache_all(void)
183 {
184 	__asm__ __volatile__(" flush ");	/*iflush*/
185 }
186 
187 void leon_flush_dcache_all(void)
188 {
189 	__asm__ __volatile__("sta %%g0, [%%g0] %0\n\t" : :
190 			     "i"(ASI_LEON_DFLUSH) : "memory");
191 }
192 
193 void leon_flush_pcache_all(struct vm_area_struct *vma, unsigned long page)
194 {
195 	if (vma->vm_flags & VM_EXEC)
196 		leon_flush_icache_all();
197 	leon_flush_dcache_all();
198 }
199 
200 void leon_flush_cache_all(void)
201 {
202 	__asm__ __volatile__(" flush ");	/*iflush*/
203 	__asm__ __volatile__("sta %%g0, [%%g0] %0\n\t" : :
204 			     "i"(ASI_LEON_DFLUSH) : "memory");
205 }
206 
207 void leon_flush_tlb_all(void)
208 {
209 	leon_flush_cache_all();
210 	__asm__ __volatile__("sta %%g0, [%0] %1\n\t" : : "r"(0x400),
211 			     "i"(ASI_LEON_MMUFLUSH) : "memory");
212 }
213 
214 /* get all cache regs */
215 void leon3_getCacheRegs(struct leon3_cacheregs *regs)
216 {
217 	unsigned long ccr, iccr, dccr;
218 
219 	if (!regs)
220 		return;
221 	/* Get Cache regs from "Cache ASI" address 0x0, 0x8 and 0xC */
222 	__asm__ __volatile__("lda [%%g0] %3, %0\n\t"
223 			     "mov 0x08, %%g1\n\t"
224 			     "lda [%%g1] %3, %1\n\t"
225 			     "mov 0x0c, %%g1\n\t"
226 			     "lda [%%g1] %3, %2\n\t"
227 			     : "=r"(ccr), "=r"(iccr), "=r"(dccr)
228 			       /* output */
229 			     : "i"(ASI_LEON_CACHEREGS)	/* input */
230 			     : "g1"	/* clobber list */
231 	    );
232 	regs->ccr = ccr;
233 	regs->iccr = iccr;
234 	regs->dccr = dccr;
235 }
236 
237 /* Due to virtual cache we need to check cache configuration if
238  * it is possible to skip flushing in some cases.
239  *
240  * Leon2 and Leon3 differ in their way of telling cache information
241  *
242  */
243 int __init leon_flush_needed(void)
244 {
245 	int flush_needed = -1;
246 	unsigned int ssize, sets;
247 	char *setStr[4] =
248 	    { "direct mapped", "2-way associative", "3-way associative",
249 		"4-way associative"
250 	};
251 	/* leon 3 */
252 	struct leon3_cacheregs cregs;
253 	leon3_getCacheRegs(&cregs);
254 	sets = (cregs.dccr & LEON3_XCCR_SETS_MASK) >> 24;
255 	/* (ssize=>realsize) 0=>1k, 1=>2k, 2=>4k, 3=>8k ... */
256 	ssize = 1 << ((cregs.dccr & LEON3_XCCR_SSIZE_MASK) >> 20);
257 
258 	printk(KERN_INFO "CACHE: %s cache, set size %dk\n",
259 	       sets > 3 ? "unknown" : setStr[sets], ssize);
260 	if ((ssize <= (PAGE_SIZE / 1024)) && (sets == 0)) {
261 		/* Set Size <= Page size  ==>
262 		   flush on every context switch not needed. */
263 		flush_needed = 0;
264 		printk(KERN_INFO "CACHE: not flushing on every context switch\n");
265 	}
266 	return flush_needed;
267 }
268 
269 void leon_switch_mm(void)
270 {
271 	flush_tlb_mm((void *)0);
272 	if (leon_flush_during_switch)
273 		leon_flush_cache_all();
274 }
275 
276 static void leon_flush_cache_mm(struct mm_struct *mm)
277 {
278 	leon_flush_cache_all();
279 }
280 
281 static void leon_flush_cache_page(struct vm_area_struct *vma, unsigned long page)
282 {
283 	leon_flush_pcache_all(vma, page);
284 }
285 
286 static void leon_flush_cache_range(struct vm_area_struct *vma,
287 				   unsigned long start,
288 				   unsigned long end)
289 {
290 	leon_flush_cache_all();
291 }
292 
293 static void leon_flush_tlb_mm(struct mm_struct *mm)
294 {
295 	leon_flush_tlb_all();
296 }
297 
298 static void leon_flush_tlb_page(struct vm_area_struct *vma,
299 				unsigned long page)
300 {
301 	leon_flush_tlb_all();
302 }
303 
304 static void leon_flush_tlb_range(struct vm_area_struct *vma,
305 				 unsigned long start,
306 				 unsigned long end)
307 {
308 	leon_flush_tlb_all();
309 }
310 
311 static void leon_flush_page_to_ram(unsigned long page)
312 {
313 	leon_flush_cache_all();
314 }
315 
316 static void leon_flush_sig_insns(struct mm_struct *mm, unsigned long page)
317 {
318 	leon_flush_cache_all();
319 }
320 
321 static void leon_flush_page_for_dma(unsigned long page)
322 {
323 	leon_flush_dcache_all();
324 }
325 
326 void __init poke_leonsparc(void)
327 {
328 }
329 
330 static const struct sparc32_cachetlb_ops leon_ops = {
331 	.cache_all	= leon_flush_cache_all,
332 	.cache_mm	= leon_flush_cache_mm,
333 	.cache_page	= leon_flush_cache_page,
334 	.cache_range	= leon_flush_cache_range,
335 	.tlb_all	= leon_flush_tlb_all,
336 	.tlb_mm		= leon_flush_tlb_mm,
337 	.tlb_page	= leon_flush_tlb_page,
338 	.tlb_range	= leon_flush_tlb_range,
339 	.page_to_ram	= leon_flush_page_to_ram,
340 	.sig_insns	= leon_flush_sig_insns,
341 	.page_for_dma	= leon_flush_page_for_dma,
342 };
343 
344 void __init init_leon(void)
345 {
346 	srmmu_name = "LEON";
347 	sparc32_cachetlb_ops = &leon_ops;
348 	poke_srmmu = poke_leonsparc;
349 
350 	leon_flush_during_switch = leon_flush_needed();
351 }
352