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/pgtable.h>
14#include <asm/pgtsrmmu.h>
15
16/* Bits in the SRMMU control register for GNU/Viking modules.
17 *
18 * -----------------------------------------------------------
19 * |impl-vers| RSV |TC|AC|SP|BM|PC|MBM|SB|IC|DC|PSO|RSV|NF|ME|
20 * -----------------------------------------------------------
21 *  31     24 23-17 16 15 14 13 12 11  10  9  8  7  6-2  1  0
22 *
23 * TC: Tablewalk Cacheable -- 0 = Twalks are not cacheable in E-cache
24 *                            1 = Twalks are cacheable in E-cache
25 *
26 * GNU/Viking will only cache tablewalks in the E-cache (mxcc) if present
27 * and never caches them internally (or so states the docs).  Therefore
28 * for machines lacking an E-cache (ie. in MBUS mode) this bit must
29 * remain cleared.
30 *
31 * AC: Alternate Cacheable -- 0 = Passthru physical accesses not cacheable
32 *                            1 = Passthru physical accesses cacheable
33 *
34 * This indicates whether accesses are cacheable when no cachable bit
35 * is present in the pte when the processor is in boot-mode or the
36 * access does not need pte's for translation (ie. pass-thru ASI's).
37 * "Cachable" is only referring to E-cache (if present) and not the
38 * on chip split I/D caches of the GNU/Viking.
39 *
40 * SP: SnooP Enable -- 0 = bus snooping off, 1 = bus snooping on
41 *
42 * This enables snooping on the GNU/Viking bus.  This must be on
43 * for the hardware cache consistency mechanisms of the GNU/Viking
44 * to work at all.  On non-mxcc GNU/Viking modules the split I/D
45 * caches will snoop regardless of whether they are enabled, this
46 * takes care of the case where the I or D or both caches are turned
47 * off yet still contain valid data.  Note also that this bit does
48 * not affect GNU/Viking store-buffer snoops, those happen if the
49 * store-buffer is enabled no matter what.
50 *
51 * BM: Boot Mode -- 0 = not in boot mode, 1 = in boot mode
52 *
53 * This indicates whether the GNU/Viking is in boot-mode or not,
54 * if it is then all instruction fetch physical addresses are
55 * computed as 0xff0000000 + low 28 bits of requested address.
56 * GNU/Viking boot-mode does not affect data accesses.  Also,
57 * in boot mode instruction accesses bypass the split on chip I/D
58 * caches, they may be cached by the GNU/MXCC if present and enabled.
59 *
60 * MBM: MBus Mode -- 0 = not in MBus mode, 1 = in MBus mode
61 *
62 * This indicated the GNU/Viking configuration present.  If in
63 * MBUS mode, the GNU/Viking lacks a GNU/MXCC E-cache.  If it is
64 * not then the GNU/Viking is on a module VBUS connected directly
65 * to a GNU/MXCC cache controller.  The GNU/MXCC can be thus connected
66 * to either an GNU/MBUS (sun4m) or the packet-switched GNU/XBus (sun4d).
67 *
68 * SB: StoreBuffer enable -- 0 = store buffer off, 1 = store buffer on
69 *
70 * The GNU/Viking store buffer allows the chip to continue execution
71 * after a store even if the data cannot be placed in one of the
72 * caches during that cycle.  If disabled, all stores operations
73 * occur synchronously.
74 *
75 * IC: Instruction Cache -- 0 = off, 1 = on
76 * DC: Data Cache -- 0 = off, 1 = 0n
77 *
78 * These bits enable the on-cpu GNU/Viking split I/D caches.  Note,
79 * as mentioned above, these caches will snoop the bus in GNU/MBUS
80 * configurations even when disabled to avoid data corruption.
81 *
82 * NF: No Fault -- 0 = faults generate traps, 1 = faults don't trap
83 * ME: MMU enable -- 0 = mmu not translating, 1 = mmu translating
84 *
85 */
86
87#define VIKING_MMUENABLE    0x00000001
88#define VIKING_NOFAULT      0x00000002
89#define VIKING_PSO          0x00000080
90#define VIKING_DCENABLE     0x00000100   /* Enable data cache */
91#define VIKING_ICENABLE     0x00000200   /* Enable instruction cache */
92#define VIKING_SBENABLE     0x00000400   /* Enable store buffer */
93#define VIKING_MMODE        0x00000800   /* MBUS mode */
94#define VIKING_PCENABLE     0x00001000   /* Enable parity checking */
95#define VIKING_BMODE        0x00002000
96#define VIKING_SPENABLE     0x00004000   /* Enable bus cache snooping */
97#define VIKING_ACENABLE     0x00008000   /* Enable alternate caching */
98#define VIKING_TCENABLE     0x00010000   /* Enable table-walks to be cached */
99#define VIKING_DPENABLE     0x00040000   /* Enable the data prefetcher */
100
101/*
102 * GNU/Viking Breakpoint Action Register fields.
103 */
104#define VIKING_ACTION_MIX   0x00001000   /* Enable multiple instructions */
105
106/*
107 * GNU/Viking Cache Tags.
108 */
109#define VIKING_PTAG_VALID   0x01000000   /* Cache block is valid */
110#define VIKING_PTAG_DIRTY   0x00010000   /* Block has been modified */
111#define VIKING_PTAG_SHARED  0x00000100   /* Shared with some other cache */
112
113#ifndef __ASSEMBLY__
114
115static inline void viking_flush_icache(void)
116{
117	__asm__ __volatile__("sta %%g0, [%%g0] %0\n\t"
118			     : /* no outputs */
119			     : "i" (ASI_M_IC_FLCLEAR)
120			     : "memory");
121}
122
123static inline void viking_flush_dcache(void)
124{
125	__asm__ __volatile__("sta %%g0, [%%g0] %0\n\t"
126			     : /* no outputs */
127			     : "i" (ASI_M_DC_FLCLEAR)
128			     : "memory");
129}
130
131static inline void viking_unlock_icache(void)
132{
133	__asm__ __volatile__("sta %%g0, [%0] %1\n\t"
134			     : /* no outputs */
135			     : "r" (0x80000000), "i" (ASI_M_IC_FLCLEAR)
136			     : "memory");
137}
138
139static inline void viking_unlock_dcache(void)
140{
141	__asm__ __volatile__("sta %%g0, [%0] %1\n\t"
142			     : /* no outputs */
143			     : "r" (0x80000000), "i" (ASI_M_DC_FLCLEAR)
144			     : "memory");
145}
146
147static inline void viking_set_bpreg(unsigned long regval)
148{
149	__asm__ __volatile__("sta %0, [%%g0] %1\n\t"
150			     : /* no outputs */
151			     : "r" (regval), "i" (ASI_M_ACTION)
152			     : "memory");
153}
154
155static inline unsigned long viking_get_bpreg(void)
156{
157	unsigned long regval;
158
159	__asm__ __volatile__("lda [%%g0] %1, %0\n\t"
160			     : "=r" (regval)
161			     : "i" (ASI_M_ACTION));
162	return regval;
163}
164
165static inline void viking_get_dcache_ptag(int set, int block,
166					      unsigned long *data)
167{
168	unsigned long ptag = ((set & 0x7f) << 5) | ((block & 0x3) << 26) |
169			     0x80000000;
170	unsigned long info, page;
171
172	__asm__ __volatile__ ("ldda [%2] %3, %%g2\n\t"
173			      "or %%g0, %%g2, %0\n\t"
174			      "or %%g0, %%g3, %1\n\t"
175			      : "=r" (info), "=r" (page)
176			      : "r" (ptag), "i" (ASI_M_DATAC_TAG)
177			      : "g2", "g3");
178	data[0] = info;
179	data[1] = page;
180}
181
182static inline void viking_mxcc_turn_off_parity(unsigned long *mregp,
183						   unsigned long *mxcc_cregp)
184{
185	unsigned long mreg = *mregp;
186	unsigned long mxcc_creg = *mxcc_cregp;
187
188	mreg &= ~(VIKING_PCENABLE);
189	mxcc_creg &= ~(MXCC_CTL_PARE);
190
191	__asm__ __volatile__ ("set 1f, %%g2\n\t"
192			      "andcc %%g2, 4, %%g0\n\t"
193			      "bne 2f\n\t"
194			      " nop\n"
195			      "1:\n\t"
196			      "sta %0, [%%g0] %3\n\t"
197			      "sta %1, [%2] %4\n\t"
198			      "b 1f\n\t"
199			      " nop\n\t"
200			      "nop\n"
201			      "2:\n\t"
202			      "sta %0, [%%g0] %3\n\t"
203			      "sta %1, [%2] %4\n"
204			      "1:\n\t"
205			      : /* no output */
206			      : "r" (mreg), "r" (mxcc_creg),
207			        "r" (MXCC_CREG), "i" (ASI_M_MMUREGS),
208			        "i" (ASI_M_MXCC)
209			      : "g2", "memory", "cc");
210	*mregp = mreg;
211	*mxcc_cregp = mxcc_creg;
212}
213
214static inline unsigned long viking_hwprobe(unsigned long vaddr)
215{
216	unsigned long val;
217
218	vaddr &= PAGE_MASK;
219	/* Probe all MMU entries. */
220	__asm__ __volatile__("lda [%1] %2, %0\n\t"
221			     : "=r" (val)
222			     : "r" (vaddr | 0x400), "i" (ASI_M_FLUSH_PROBE));
223	if (!val)
224		return 0;
225
226	/* Probe region. */
227	__asm__ __volatile__("lda [%1] %2, %0\n\t"
228			     : "=r" (val)
229			     : "r" (vaddr | 0x200), "i" (ASI_M_FLUSH_PROBE));
230	if ((val & SRMMU_ET_MASK) == SRMMU_ET_PTE) {
231		vaddr &= ~PGDIR_MASK;
232		vaddr >>= PAGE_SHIFT;
233		return val | (vaddr << 8);
234	}
235
236	/* Probe segment. */
237	__asm__ __volatile__("lda [%1] %2, %0\n\t"
238			     : "=r" (val)
239			     : "r" (vaddr | 0x100), "i" (ASI_M_FLUSH_PROBE));
240	if ((val & SRMMU_ET_MASK) == SRMMU_ET_PTE) {
241		vaddr &= ~PMD_MASK;
242		vaddr >>= PAGE_SHIFT;
243		return val | (vaddr << 8);
244	}
245
246	/* Probe page. */
247	__asm__ __volatile__("lda [%1] %2, %0\n\t"
248			     : "=r" (val)
249			     : "r" (vaddr), "i" (ASI_M_FLUSH_PROBE));
250	return val;
251}
252
253#endif /* !__ASSEMBLY__ */
254
255#endif /* !(_SPARC_VIKING_H) */
256