xref: /linux/arch/sparc/mm/leon_mm.c (revision d524dac9279b6a41ffdf7ff7958c577f2e387db6)
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 int leon_flush_during_switch = 1;
19 int srmmu_swprobe_trace;
20 
21 unsigned long srmmu_swprobe(unsigned long vaddr, unsigned long *paddr)
22 {
23 
24 	unsigned int ctxtbl;
25 	unsigned int pgd, pmd, ped;
26 	unsigned int ptr;
27 	unsigned int lvl, pte, paddrbase;
28 	unsigned int ctx;
29 	unsigned int paddr_calc;
30 
31 	paddrbase = 0;
32 
33 	if (srmmu_swprobe_trace)
34 		printk(KERN_INFO "swprobe: trace on\n");
35 
36 	ctxtbl = srmmu_get_ctable_ptr();
37 	if (!(ctxtbl)) {
38 		if (srmmu_swprobe_trace)
39 			printk(KERN_INFO "swprobe: srmmu_get_ctable_ptr returned 0=>0\n");
40 		return 0;
41 	}
42 	if (!_pfn_valid(PFN(ctxtbl))) {
43 		if (srmmu_swprobe_trace)
44 			printk(KERN_INFO
45 			       "swprobe: !_pfn_valid(%x)=>0\n",
46 			       PFN(ctxtbl));
47 		return 0;
48 	}
49 
50 	ctx = srmmu_get_context();
51 	if (srmmu_swprobe_trace)
52 		printk(KERN_INFO "swprobe:  --- ctx (%x) ---\n", ctx);
53 
54 	pgd = LEON_BYPASS_LOAD_PA(ctxtbl + (ctx * 4));
55 
56 	if (((pgd & SRMMU_ET_MASK) == SRMMU_ET_PTE)) {
57 		if (srmmu_swprobe_trace)
58 			printk(KERN_INFO "swprobe: pgd is entry level 3\n");
59 		lvl = 3;
60 		pte = pgd;
61 		paddrbase = pgd & _SRMMU_PTE_PMASK_LEON;
62 		goto ready;
63 	}
64 	if (((pgd & SRMMU_ET_MASK) != SRMMU_ET_PTD)) {
65 		if (srmmu_swprobe_trace)
66 			printk(KERN_INFO "swprobe: pgd is invalid => 0\n");
67 		return 0;
68 	}
69 
70 	if (srmmu_swprobe_trace)
71 		printk(KERN_INFO "swprobe:  --- pgd (%x) ---\n", pgd);
72 
73 	ptr = (pgd & SRMMU_PTD_PMASK) << 4;
74 	ptr += ((((vaddr) >> LEON_PGD_SH) & LEON_PGD_M) * 4);
75 	if (!_pfn_valid(PFN(ptr)))
76 		return 0;
77 
78 	pmd = LEON_BYPASS_LOAD_PA(ptr);
79 	if (((pmd & SRMMU_ET_MASK) == SRMMU_ET_PTE)) {
80 		if (srmmu_swprobe_trace)
81 			printk(KERN_INFO "swprobe: pmd is entry level 2\n");
82 		lvl = 2;
83 		pte = pmd;
84 		paddrbase = pmd & _SRMMU_PTE_PMASK_LEON;
85 		goto ready;
86 	}
87 	if (((pmd & SRMMU_ET_MASK) != SRMMU_ET_PTD)) {
88 		if (srmmu_swprobe_trace)
89 			printk(KERN_INFO "swprobe: pmd is invalid => 0\n");
90 		return 0;
91 	}
92 
93 	if (srmmu_swprobe_trace)
94 		printk(KERN_INFO "swprobe:  --- pmd (%x) ---\n", pmd);
95 
96 	ptr = (pmd & SRMMU_PTD_PMASK) << 4;
97 	ptr += (((vaddr >> LEON_PMD_SH) & LEON_PMD_M) * 4);
98 	if (!_pfn_valid(PFN(ptr))) {
99 		if (srmmu_swprobe_trace)
100 			printk(KERN_INFO "swprobe: !_pfn_valid(%x)=>0\n",
101 			       PFN(ptr));
102 		return 0;
103 	}
104 
105 	ped = LEON_BYPASS_LOAD_PA(ptr);
106 
107 	if (((ped & SRMMU_ET_MASK) == SRMMU_ET_PTE)) {
108 		if (srmmu_swprobe_trace)
109 			printk(KERN_INFO "swprobe: ped is entry level 1\n");
110 		lvl = 1;
111 		pte = ped;
112 		paddrbase = ped & _SRMMU_PTE_PMASK_LEON;
113 		goto ready;
114 	}
115 	if (((ped & SRMMU_ET_MASK) != SRMMU_ET_PTD)) {
116 		if (srmmu_swprobe_trace)
117 			printk(KERN_INFO "swprobe: ped is invalid => 0\n");
118 		return 0;
119 	}
120 
121 	if (srmmu_swprobe_trace)
122 		printk(KERN_INFO "swprobe:  --- ped (%x) ---\n", ped);
123 
124 	ptr = (ped & SRMMU_PTD_PMASK) << 4;
125 	ptr += (((vaddr >> LEON_PTE_SH) & LEON_PTE_M) * 4);
126 	if (!_pfn_valid(PFN(ptr)))
127 		return 0;
128 
129 	ptr = LEON_BYPASS_LOAD_PA(ptr);
130 	if (((ptr & SRMMU_ET_MASK) == SRMMU_ET_PTE)) {
131 		if (srmmu_swprobe_trace)
132 			printk(KERN_INFO "swprobe: ptr is entry level 0\n");
133 		lvl = 0;
134 		pte = ptr;
135 		paddrbase = ptr & _SRMMU_PTE_PMASK_LEON;
136 		goto ready;
137 	}
138 	if (srmmu_swprobe_trace)
139 		printk(KERN_INFO "swprobe: ptr is invalid => 0\n");
140 	return 0;
141 
142 ready:
143 	switch (lvl) {
144 	case 0:
145 		paddr_calc =
146 		    (vaddr & ~(-1 << LEON_PTE_SH)) | ((pte & ~0xff) << 4);
147 		break;
148 	case 1:
149 		paddr_calc =
150 		    (vaddr & ~(-1 << LEON_PMD_SH)) | ((pte & ~0xff) << 4);
151 		break;
152 	case 2:
153 		paddr_calc =
154 		    (vaddr & ~(-1 << LEON_PGD_SH)) | ((pte & ~0xff) << 4);
155 		break;
156 	default:
157 	case 3:
158 		paddr_calc = vaddr;
159 		break;
160 	}
161 	if (srmmu_swprobe_trace)
162 		printk(KERN_INFO "swprobe: padde %x\n", paddr_calc);
163 	if (paddr)
164 		*paddr = paddr_calc;
165 	return paddrbase;
166 }
167 
168 void leon_flush_icache_all(void)
169 {
170 	__asm__ __volatile__(" flush ");	/*iflush*/
171 }
172 
173 void leon_flush_dcache_all(void)
174 {
175 	__asm__ __volatile__("sta %%g0, [%%g0] %0\n\t" : :
176 			     "i"(ASI_LEON_DFLUSH) : "memory");
177 }
178 
179 void leon_flush_pcache_all(struct vm_area_struct *vma, unsigned long page)
180 {
181 	if (vma->vm_flags & VM_EXEC)
182 		leon_flush_icache_all();
183 	leon_flush_dcache_all();
184 }
185 
186 void leon_flush_cache_all(void)
187 {
188 	__asm__ __volatile__(" flush ");	/*iflush*/
189 	__asm__ __volatile__("sta %%g0, [%%g0] %0\n\t" : :
190 			     "i"(ASI_LEON_DFLUSH) : "memory");
191 }
192 
193 void leon_flush_tlb_all(void)
194 {
195 	leon_flush_cache_all();
196 	__asm__ __volatile__("sta %%g0, [%0] %1\n\t" : : "r"(0x400),
197 			     "i"(ASI_LEON_MMUFLUSH) : "memory");
198 }
199 
200 /* get all cache regs */
201 void leon3_getCacheRegs(struct leon3_cacheregs *regs)
202 {
203 	unsigned long ccr, iccr, dccr;
204 
205 	if (!regs)
206 		return;
207 	/* Get Cache regs from "Cache ASI" address 0x0, 0x8 and 0xC */
208 	__asm__ __volatile__("lda [%%g0] %3, %0\n\t"
209 			     "mov 0x08, %%g1\n\t"
210 			     "lda [%%g1] %3, %1\n\t"
211 			     "mov 0x0c, %%g1\n\t"
212 			     "lda [%%g1] %3, %2\n\t"
213 			     : "=r"(ccr), "=r"(iccr), "=r"(dccr)
214 			       /* output */
215 			     : "i"(ASI_LEON_CACHEREGS)	/* input */
216 			     : "g1"	/* clobber list */
217 	    );
218 	regs->ccr = ccr;
219 	regs->iccr = iccr;
220 	regs->dccr = dccr;
221 }
222 
223 /* Due to virtual cache we need to check cache configuration if
224  * it is possible to skip flushing in some cases.
225  *
226  * Leon2 and Leon3 differ in their way of telling cache information
227  *
228  */
229 int leon_flush_needed(void)
230 {
231 	int flush_needed = -1;
232 	unsigned int ssize, sets;
233 	char *setStr[4] =
234 	    { "direct mapped", "2-way associative", "3-way associative",
235 		"4-way associative"
236 	};
237 	/* leon 3 */
238 	struct leon3_cacheregs cregs;
239 	leon3_getCacheRegs(&cregs);
240 	sets = (cregs.dccr & LEON3_XCCR_SETS_MASK) >> 24;
241 	/* (ssize=>realsize) 0=>1k, 1=>2k, 2=>4k, 3=>8k ... */
242 	ssize = 1 << ((cregs.dccr & LEON3_XCCR_SSIZE_MASK) >> 20);
243 
244 	printk(KERN_INFO "CACHE: %s cache, set size %dk\n",
245 	       sets > 3 ? "unknown" : setStr[sets], ssize);
246 	if ((ssize <= (PAGE_SIZE / 1024)) && (sets == 0)) {
247 		/* Set Size <= Page size  ==>
248 		   flush on every context switch not needed. */
249 		flush_needed = 0;
250 		printk(KERN_INFO "CACHE: not flushing on every context switch\n");
251 	}
252 	return flush_needed;
253 }
254 
255 void leon_switch_mm(void)
256 {
257 	flush_tlb_mm((void *)0);
258 	if (leon_flush_during_switch)
259 		leon_flush_cache_all();
260 }
261