xref: /openbmc/linux/arch/sparc/include/asm/viking.h (revision 6c33a6f4)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * viking.h:  Defines specific to the GNU/Viking MBUS module.
4  *            This is SRMMU stuff.
5  *
6  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
7  */
8 #ifndef _SPARC_VIKING_H
9 #define _SPARC_VIKING_H
10 
11 #include <asm/asi.h>
12 #include <asm/mxcc.h>
13 #include <asm/pgtsrmmu.h>
14 
15 /* Bits in the SRMMU control register for GNU/Viking modules.
16  *
17  * -----------------------------------------------------------
18  * |impl-vers| RSV |TC|AC|SP|BM|PC|MBM|SB|IC|DC|PSO|RSV|NF|ME|
19  * -----------------------------------------------------------
20  *  31     24 23-17 16 15 14 13 12 11  10  9  8  7  6-2  1  0
21  *
22  * TC: Tablewalk Cacheable -- 0 = Twalks are not cacheable in E-cache
23  *                            1 = Twalks are cacheable in E-cache
24  *
25  * GNU/Viking will only cache tablewalks in the E-cache (mxcc) if present
26  * and never caches them internally (or so states the docs).  Therefore
27  * for machines lacking an E-cache (ie. in MBUS mode) this bit must
28  * remain cleared.
29  *
30  * AC: Alternate Cacheable -- 0 = Passthru physical accesses not cacheable
31  *                            1 = Passthru physical accesses cacheable
32  *
33  * This indicates whether accesses are cacheable when no cachable bit
34  * is present in the pte when the processor is in boot-mode or the
35  * access does not need pte's for translation (ie. pass-thru ASI's).
36  * "Cachable" is only referring to E-cache (if present) and not the
37  * on chip split I/D caches of the GNU/Viking.
38  *
39  * SP: SnooP Enable -- 0 = bus snooping off, 1 = bus snooping on
40  *
41  * This enables snooping on the GNU/Viking bus.  This must be on
42  * for the hardware cache consistency mechanisms of the GNU/Viking
43  * to work at all.  On non-mxcc GNU/Viking modules the split I/D
44  * caches will snoop regardless of whether they are enabled, this
45  * takes care of the case where the I or D or both caches are turned
46  * off yet still contain valid data.  Note also that this bit does
47  * not affect GNU/Viking store-buffer snoops, those happen if the
48  * store-buffer is enabled no matter what.
49  *
50  * BM: Boot Mode -- 0 = not in boot mode, 1 = in boot mode
51  *
52  * This indicates whether the GNU/Viking is in boot-mode or not,
53  * if it is then all instruction fetch physical addresses are
54  * computed as 0xff0000000 + low 28 bits of requested address.
55  * GNU/Viking boot-mode does not affect data accesses.  Also,
56  * in boot mode instruction accesses bypass the split on chip I/D
57  * caches, they may be cached by the GNU/MXCC if present and enabled.
58  *
59  * MBM: MBus Mode -- 0 = not in MBus mode, 1 = in MBus mode
60  *
61  * This indicated the GNU/Viking configuration present.  If in
62  * MBUS mode, the GNU/Viking lacks a GNU/MXCC E-cache.  If it is
63  * not then the GNU/Viking is on a module VBUS connected directly
64  * to a GNU/MXCC cache controller.  The GNU/MXCC can be thus connected
65  * to either an GNU/MBUS (sun4m) or the packet-switched GNU/XBus (sun4d).
66  *
67  * SB: StoreBuffer enable -- 0 = store buffer off, 1 = store buffer on
68  *
69  * The GNU/Viking store buffer allows the chip to continue execution
70  * after a store even if the data cannot be placed in one of the
71  * caches during that cycle.  If disabled, all stores operations
72  * occur synchronously.
73  *
74  * IC: Instruction Cache -- 0 = off, 1 = on
75  * DC: Data Cache -- 0 = off, 1 = 0n
76  *
77  * These bits enable the on-cpu GNU/Viking split I/D caches.  Note,
78  * as mentioned above, these caches will snoop the bus in GNU/MBUS
79  * configurations even when disabled to avoid data corruption.
80  *
81  * NF: No Fault -- 0 = faults generate traps, 1 = faults don't trap
82  * ME: MMU enable -- 0 = mmu not translating, 1 = mmu translating
83  *
84  */
85 
86 #define VIKING_MMUENABLE    0x00000001
87 #define VIKING_NOFAULT      0x00000002
88 #define VIKING_PSO          0x00000080
89 #define VIKING_DCENABLE     0x00000100   /* Enable data cache */
90 #define VIKING_ICENABLE     0x00000200   /* Enable instruction cache */
91 #define VIKING_SBENABLE     0x00000400   /* Enable store buffer */
92 #define VIKING_MMODE        0x00000800   /* MBUS mode */
93 #define VIKING_PCENABLE     0x00001000   /* Enable parity checking */
94 #define VIKING_BMODE        0x00002000
95 #define VIKING_SPENABLE     0x00004000   /* Enable bus cache snooping */
96 #define VIKING_ACENABLE     0x00008000   /* Enable alternate caching */
97 #define VIKING_TCENABLE     0x00010000   /* Enable table-walks to be cached */
98 #define VIKING_DPENABLE     0x00040000   /* Enable the data prefetcher */
99 
100 /*
101  * GNU/Viking Breakpoint Action Register fields.
102  */
103 #define VIKING_ACTION_MIX   0x00001000   /* Enable multiple instructions */
104 
105 /*
106  * GNU/Viking Cache Tags.
107  */
108 #define VIKING_PTAG_VALID   0x01000000   /* Cache block is valid */
109 #define VIKING_PTAG_DIRTY   0x00010000   /* Block has been modified */
110 #define VIKING_PTAG_SHARED  0x00000100   /* Shared with some other cache */
111 
112 #ifndef __ASSEMBLY__
113 
114 static inline void viking_flush_icache(void)
115 {
116 	__asm__ __volatile__("sta %%g0, [%%g0] %0\n\t"
117 			     : /* no outputs */
118 			     : "i" (ASI_M_IC_FLCLEAR)
119 			     : "memory");
120 }
121 
122 static inline void viking_flush_dcache(void)
123 {
124 	__asm__ __volatile__("sta %%g0, [%%g0] %0\n\t"
125 			     : /* no outputs */
126 			     : "i" (ASI_M_DC_FLCLEAR)
127 			     : "memory");
128 }
129 
130 static inline void viking_unlock_icache(void)
131 {
132 	__asm__ __volatile__("sta %%g0, [%0] %1\n\t"
133 			     : /* no outputs */
134 			     : "r" (0x80000000), "i" (ASI_M_IC_FLCLEAR)
135 			     : "memory");
136 }
137 
138 static inline void viking_unlock_dcache(void)
139 {
140 	__asm__ __volatile__("sta %%g0, [%0] %1\n\t"
141 			     : /* no outputs */
142 			     : "r" (0x80000000), "i" (ASI_M_DC_FLCLEAR)
143 			     : "memory");
144 }
145 
146 static inline void viking_set_bpreg(unsigned long regval)
147 {
148 	__asm__ __volatile__("sta %0, [%%g0] %1\n\t"
149 			     : /* no outputs */
150 			     : "r" (regval), "i" (ASI_M_ACTION)
151 			     : "memory");
152 }
153 
154 static inline unsigned long viking_get_bpreg(void)
155 {
156 	unsigned long regval;
157 
158 	__asm__ __volatile__("lda [%%g0] %1, %0\n\t"
159 			     : "=r" (regval)
160 			     : "i" (ASI_M_ACTION));
161 	return regval;
162 }
163 
164 static inline void viking_get_dcache_ptag(int set, int block,
165 					      unsigned long *data)
166 {
167 	unsigned long ptag = ((set & 0x7f) << 5) | ((block & 0x3) << 26) |
168 			     0x80000000;
169 	unsigned long info, page;
170 
171 	__asm__ __volatile__ ("ldda [%2] %3, %%g2\n\t"
172 			      "or %%g0, %%g2, %0\n\t"
173 			      "or %%g0, %%g3, %1\n\t"
174 			      : "=r" (info), "=r" (page)
175 			      : "r" (ptag), "i" (ASI_M_DATAC_TAG)
176 			      : "g2", "g3");
177 	data[0] = info;
178 	data[1] = page;
179 }
180 
181 static inline void viking_mxcc_turn_off_parity(unsigned long *mregp,
182 						   unsigned long *mxcc_cregp)
183 {
184 	unsigned long mreg = *mregp;
185 	unsigned long mxcc_creg = *mxcc_cregp;
186 
187 	mreg &= ~(VIKING_PCENABLE);
188 	mxcc_creg &= ~(MXCC_CTL_PARE);
189 
190 	__asm__ __volatile__ ("set 1f, %%g2\n\t"
191 			      "andcc %%g2, 4, %%g0\n\t"
192 			      "bne 2f\n\t"
193 			      " nop\n"
194 			      "1:\n\t"
195 			      "sta %0, [%%g0] %3\n\t"
196 			      "sta %1, [%2] %4\n\t"
197 			      "b 1f\n\t"
198 			      " nop\n\t"
199 			      "nop\n"
200 			      "2:\n\t"
201 			      "sta %0, [%%g0] %3\n\t"
202 			      "sta %1, [%2] %4\n"
203 			      "1:\n\t"
204 			      : /* no output */
205 			      : "r" (mreg), "r" (mxcc_creg),
206 			        "r" (MXCC_CREG), "i" (ASI_M_MMUREGS),
207 			        "i" (ASI_M_MXCC)
208 			      : "g2", "memory", "cc");
209 	*mregp = mreg;
210 	*mxcc_cregp = mxcc_creg;
211 }
212 
213 static inline unsigned long viking_hwprobe(unsigned long vaddr)
214 {
215 	unsigned long val;
216 
217 	vaddr &= PAGE_MASK;
218 	/* Probe all MMU entries. */
219 	__asm__ __volatile__("lda [%1] %2, %0\n\t"
220 			     : "=r" (val)
221 			     : "r" (vaddr | 0x400), "i" (ASI_M_FLUSH_PROBE));
222 	if (!val)
223 		return 0;
224 
225 	/* Probe region. */
226 	__asm__ __volatile__("lda [%1] %2, %0\n\t"
227 			     : "=r" (val)
228 			     : "r" (vaddr | 0x200), "i" (ASI_M_FLUSH_PROBE));
229 	if ((val & SRMMU_ET_MASK) == SRMMU_ET_PTE) {
230 		vaddr &= ~SRMMU_PGDIR_MASK;
231 		vaddr >>= PAGE_SHIFT;
232 		return val | (vaddr << 8);
233 	}
234 
235 	/* Probe segment. */
236 	__asm__ __volatile__("lda [%1] %2, %0\n\t"
237 			     : "=r" (val)
238 			     : "r" (vaddr | 0x100), "i" (ASI_M_FLUSH_PROBE));
239 	if ((val & SRMMU_ET_MASK) == SRMMU_ET_PTE) {
240 		vaddr &= ~SRMMU_REAL_PMD_MASK;
241 		vaddr >>= PAGE_SHIFT;
242 		return val | (vaddr << 8);
243 	}
244 
245 	/* Probe page. */
246 	__asm__ __volatile__("lda [%1] %2, %0\n\t"
247 			     : "=r" (val)
248 			     : "r" (vaddr), "i" (ASI_M_FLUSH_PROBE));
249 	return val;
250 }
251 
252 #endif /* !__ASSEMBLY__ */
253 
254 #endif /* !(_SPARC_VIKING_H) */
255