src/cpus/memory_sh.c

/*
 *  Copyright (C) 2006-2007  Anders Gavare.  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright  
 *     notice, this list of conditions and the following disclaimer in the 
 *     documentation and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 *  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE   
 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 *  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 *  OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 *  OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 *  SUCH DAMAGE.
 *
 *
 *  $Id: memory_sh.c,v 1.19 2007/04/16 15:11:31 debug Exp $
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "cpu.h"
#include "machine.h"
#include "memory.h"
#include "misc.h"

#include "sh4_exception.h"
#include "sh4_mmu.h"


/*
 *  translate_via_mmu():
 *
 *  Scan the UTLB for a matching virtual address. If a match was found, then
 *  check permission bits etc. If everything was ok, then return the physical
 *  page address, otherwise cause an exception.
 *
 *  The implementation should (hopefully) be quite complete, except for lack
 *  of "Multiple matching entries" detection. (On a real CPU, these would
 *  cause exceptions.)
 *
 *  Same return values as sh_translate_v2p().
 */
static int translate_via_mmu(struct cpu *cpu, uint32_t vaddr,
        uint64_t *return_paddr, int flags)
{
        int wf = flags & FLAG_WRITEFLAG;
        int i, urb, urc, require_asid_match, cur_asid, expevt = 0;
        uint32_t hi, lo = 0, mask = 0;
        int sh;         /*  Shared  */
        int d;          /*  Dirty bit  */
        int v;          /*  Valid bit  */
        int pr;         /*  Protection  */
        int i_start;

        cur_asid = cpu->cd.sh.pteh & SH4_PTEH_ASID_MASK;
        require_asid_match = !(cpu->cd.sh.mmucr & SH4_MMUCR_SV)
            || !(cpu->cd.sh.sr & SH_SR_MD);

        if (!(flags & FLAG_NOEXCEPTIONS)) {
                /*
                 *  Increase URC every time the UTLB is accessed. (Note:
                 *  According to the SH4 manual, the URC should not be
                 *  increased when running the ldtlb instruction. Perhaps this
                 *  is a good place? Perhaps it is better to just set it to a
                 *  random value? TODO: Find out.
                 */
                urb = (cpu->cd.sh.mmucr & SH4_MMUCR_URB_MASK) >>
                    SH4_MMUCR_URB_SHIFT;
                urc = (cpu->cd.sh.mmucr & SH4_MMUCR_URC_MASK) >>
                    SH4_MMUCR_URC_SHIFT;

                /*  fatal("urc = %i  ==>  ", urc);  */
                urc ++;
                if (urc >= SH_N_UTLB_ENTRIES || (urb > 0 && urc == urb))
                        urc = 0;
                /*  fatal("%i\n", urc);  */

                cpu->cd.sh.mmucr &= ~SH4_MMUCR_URC_MASK;
                cpu->cd.sh.mmucr |= (urc << SH4_MMUCR_URC_SHIFT);
        }

        /*
         *  When doing Instruction lookups, the ITLB should be scanned first.
         *  This is done by using negative i. (Ugly hack, but works.)
         */
        if (flags & FLAG_INSTR)
                i_start = -SH_N_ITLB_ENTRIES;
        else
                i_start = 0;

        for (i=i_start; i<SH_N_UTLB_ENTRIES; i++) {
                if (i<0) {
                        hi = cpu->cd.sh.itlb_hi[i + SH_N_ITLB_ENTRIES];
                        lo = cpu->cd.sh.itlb_lo[i + SH_N_ITLB_ENTRIES];
                } else {
                        hi = cpu->cd.sh.utlb_hi[i];
                        lo = cpu->cd.sh.utlb_lo[i];
                }
                mask = 0xfff00000;

                v = lo & SH4_PTEL_V;
                if (!v)
                        continue;

                switch (lo & SH4_PTEL_SZ_MASK) {
                case SH4_PTEL_SZ_1K:  mask = 0xfffffc00; break;
                case SH4_PTEL_SZ_4K:  mask = 0xfffff000; break;
                case SH4_PTEL_SZ_64K: mask = 0xffff0000; break;
                /*  case SH4_PTEL_SZ_1M:  mask = 0xfff00000; break;  */
                }

                if ((hi & mask) != (vaddr & mask))
                        continue;

                sh = lo & SH4_PTEL_SH;

                if (!sh && require_asid_match) {
                        int asid = hi & SH4_PTEH_ASID_MASK;
                        if (asid != cur_asid)
                                continue;
                }

                /*  Note/TODO: Check for multiple matches is not implemented. */

                break;
        }

        /*  Virtual address not found? Then it's a TLB miss.  */
        if (i == SH_N_UTLB_ENTRIES)
                goto tlb_miss;

        /*  Matching address found! Let's see whether it is
            readable/writable, etc.:  */
        d = lo & SH4_PTEL_D? 1 : 0;
        pr = (lo & SH4_PTEL_PR_MASK) >> SH4_PTEL_PR_SHIFT;

        *return_paddr = (vaddr & ~mask) | (lo & mask & 0x1fffffff);

        if (flags & FLAG_INSTR) {
                /*
                 *  Instruction access:
                 *
                 *  If a matching entry wasn't found in the ITLB, but in the
                 *  UTLB, then copy it to a random place in the ITLB.
                 */
                if (i >= 0 && !(flags & FLAG_NOEXCEPTIONS)) {
                        int r = random() % SH_N_ITLB_ENTRIES;

                        /*  NOTE: Make sure that the old mapping for
                            that itlb entry is invalidated:  */
                        cpu->invalidate_translation_caches(cpu,
                            cpu->cd.sh.itlb_hi[r] & ~0xfff, INVALIDATE_VADDR);

                        cpu->invalidate_code_translation(cpu,
                            cpu->cd.sh.utlb_lo[i] & ~0xfff, INVALIDATE_PADDR);

                        cpu->cd.sh.itlb_hi[r] = cpu->cd.sh.utlb_hi[i];
                        cpu->cd.sh.itlb_lo[r] = cpu->cd.sh.utlb_lo[i];
                }

                /*  Permission checks:  */
                if (cpu->cd.sh.sr & SH_SR_MD)
                        return 1;
                if (!(pr & 2))
                        goto protection_violation;

                return 1;
        }

        /*  Data access:  */
        if (cpu->cd.sh.sr & SH_SR_MD) {
                /*  Kernel access:  */
                switch (pr) {
                case 0:
                case 2: if (wf)
                                goto protection_violation;
                        return 1;
                case 1:
                case 3: if (wf && !d)
                                goto initial_write_exception;
                        return 1 + d;
                }
        }

        /*  User access  */
        switch (pr) {
        case 0:
        case 1: goto protection_violation;
        case 2: if (wf)
                        goto protection_violation;
                return 1;
        case 3: if (wf && !d)
                        goto initial_write_exception;
                return 1 + d;
        }


tlb_miss:
        expevt = wf? EXPEVT_TLB_MISS_ST : EXPEVT_TLB_MISS_LD;
        goto exception;

protection_violation:
        expevt = wf? EXPEVT_TLB_PROT_ST : EXPEVT_TLB_PROT_LD;
        goto exception;

initial_write_exception:
        expevt = EXPEVT_TLB_MOD;


exception:
        if (flags & FLAG_NOEXCEPTIONS) {
                *return_paddr = 0;
                return 2;
        }

        sh_exception(cpu, expevt, 0, vaddr);

        return 0;
}


/*
 *  sh_translate_v2p():
 *
 *  Return values:
 *
 *      0       No access to the virtual address.
 *      1       return_paddr contains the physical address, the page is
 *              available as read-only.
 *      2       Same as 1, but the page is available as read/write.
 */
int sh_translate_v2p(struct cpu *cpu, uint64_t vaddr64, uint64_t *return_paddr,
        int flags)
{
        int user = cpu->cd.sh.sr & SH_SR_MD? 0 : 1;
        uint32_t vaddr = vaddr64;

        /*  U0/P0: Userspace addresses, or P3: Kernel virtual memory.  */
        if (!(vaddr & 0x80000000) ||
            (vaddr >= 0xc0000000 && vaddr < 0xe0000000)) {
                /*  Address translation turned off?  */
                if (!(cpu->cd.sh.mmucr & SH4_MMUCR_AT)) {
                        /*  Then return raw physical address:  */
                        *return_paddr = vaddr & 0x1fffffff;
                        return 2;
                }

                /*  Perform translation via the MMU:  */
                return translate_via_mmu(cpu, vaddr, return_paddr, flags);
        }

        /*  Store queue region:  */
        if (vaddr >= 0xe0000000 && vaddr < 0xe4000000) {
                /*  Note/TODO: Take SH4_MMUCR_SQMD into account.  */
                *return_paddr = vaddr;
                return 2;
        }

        if (user) {
                if (flags & FLAG_NOEXCEPTIONS) {
                        *return_paddr = 0;
                        return 2;
                }

                fatal("Userspace tried to access non-user space memory."
                    " TODO: cause exception! (vaddr=0x%08"PRIx32"\n",
                    (uint32_t) vaddr);
                exit(1);
        }

        /*  P1,P2: Direct-mapped physical memory.  */
        if (vaddr >= 0x80000000 && vaddr < 0xc0000000) {
                *return_paddr = vaddr & 0x1fffffff;
                return 2;
        }

        if (flags & FLAG_INSTR) {
                fatal("TODO: instr at 0x%08"PRIx32"\n", (uint32_t)vaddr);
                exit(1);
        }

        /*  P4: Special registers mapped at 0xf0000000 .. 0xffffffff:  */
        if ((vaddr & 0xf0000000) == 0xf0000000) {
                *return_paddr = vaddr;
                return 2;
        }

        if (flags & FLAG_NOEXCEPTIONS) {
                *return_paddr = 0;
                return 2;
        }

        /*  TODO  */
        fatal("Unimplemented SH vaddr 0x%08"PRIx32"\n", (uint32_t)vaddr);
        exit(1);

        return 0;
}

1	/*
2	* Copyright (C) 2006-2007 Anders Gavare. All rights reserved.
3	*
4	* Redistribution and use in source and binary forms, with or without
5	* modification, are permitted provided that the following conditions are met:
6	*
7	* 1. Redistributions of source code must retain the above copyright
8	* notice, this list of conditions and the following disclaimer.
9	* 2. Redistributions in binary form must reproduce the above copyright
10	* notice, this list of conditions and the following disclaimer in the
11	* documentation and/or other materials provided with the distribution.
12	* 3. The name of the author may not be used to endorse or promote products
13	* derived from this software without specific prior written permission.
14	*
15	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18	* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25	* SUCH DAMAGE.
26	*
27	*
28	* $Id: memory_sh.c,v 1.19 2007/04/16 15:11:31 debug Exp $
29	*/
30
31	#include <stdio.h>
32	#include <stdlib.h>
33	#include <string.h>
34
35	#include "cpu.h"
36	#include "machine.h"
37	#include "memory.h"
38	#include "misc.h"
39
40	#include "sh4_exception.h"
41	#include "sh4_mmu.h"
42
43
44	/*
45	* translate_via_mmu():
46	*
47	* Scan the UTLB for a matching virtual address. If a match was found, then
48	* check permission bits etc. If everything was ok, then return the physical
49	* page address, otherwise cause an exception.
50	*
51	* The implementation should (hopefully) be quite complete, except for lack
52	* of "Multiple matching entries" detection. (On a real CPU, these would
53	* cause exceptions.)
54	*
55	* Same return values as sh_translate_v2p().
56	*/
57	static int translate_via_mmu(struct cpu *cpu, uint32_t vaddr,
58	uint64_t *return_paddr, int flags)
59	{
60	int wf = flags & FLAG_WRITEFLAG;
61	int i, urb, urc, require_asid_match, cur_asid, expevt = 0;
62	uint32_t hi, lo = 0, mask = 0;
63	int sh; /* Shared */
64	int d; /* Dirty bit */
65	int v; /* Valid bit */
66	int pr; /* Protection */
67	int i_start;
68
69	cur_asid = cpu->cd.sh.pteh & SH4_PTEH_ASID_MASK;
70	require_asid_match = !(cpu->cd.sh.mmucr & SH4_MMUCR_SV)
71	\|\| !(cpu->cd.sh.sr & SH_SR_MD);
72
73	if (!(flags & FLAG_NOEXCEPTIONS)) {
74	/*
75	* Increase URC every time the UTLB is accessed. (Note:
76	* According to the SH4 manual, the URC should not be
77	* increased when running the ldtlb instruction. Perhaps this
78	* is a good place? Perhaps it is better to just set it to a
79	* random value? TODO: Find out.
80	*/
81	urb = (cpu->cd.sh.mmucr & SH4_MMUCR_URB_MASK) >>
82	SH4_MMUCR_URB_SHIFT;
83	urc = (cpu->cd.sh.mmucr & SH4_MMUCR_URC_MASK) >>
84	SH4_MMUCR_URC_SHIFT;
85
86	/* fatal("urc = %i ==> ", urc); */
87	urc ++;
88	if (urc >= SH_N_UTLB_ENTRIES \|\| (urb > 0 && urc == urb))
89	urc = 0;
90	/* fatal("%i\n", urc); */
91
92	cpu->cd.sh.mmucr &= ~SH4_MMUCR_URC_MASK;
93	cpu->cd.sh.mmucr \|= (urc << SH4_MMUCR_URC_SHIFT);
94	}
95
96	/*
97	* When doing Instruction lookups, the ITLB should be scanned first.
98	* This is done by using negative i. (Ugly hack, but works.)
99	*/
100	if (flags & FLAG_INSTR)
101	i_start = -SH_N_ITLB_ENTRIES;
102	else
103	i_start = 0;
104
105	for (i=i_start; i<SH_N_UTLB_ENTRIES; i++) {
106	if (i<0) {
107	hi = cpu->cd.sh.itlb_hi[i + SH_N_ITLB_ENTRIES];
108	lo = cpu->cd.sh.itlb_lo[i + SH_N_ITLB_ENTRIES];
109	} else {
110	hi = cpu->cd.sh.utlb_hi[i];
111	lo = cpu->cd.sh.utlb_lo[i];
112	}
113	mask = 0xfff00000;
114
115	v = lo & SH4_PTEL_V;
116	if (!v)
117	continue;
118
119	switch (lo & SH4_PTEL_SZ_MASK) {
120	case SH4_PTEL_SZ_1K: mask = 0xfffffc00; break;
121	case SH4_PTEL_SZ_4K: mask = 0xfffff000; break;
122	case SH4_PTEL_SZ_64K: mask = 0xffff0000; break;
123	/* case SH4_PTEL_SZ_1M: mask = 0xfff00000; break; */
124	}
125
126	if ((hi & mask) != (vaddr & mask))
127	continue;
128
129	sh = lo & SH4_PTEL_SH;
130
131	if (!sh && require_asid_match) {
132	int asid = hi & SH4_PTEH_ASID_MASK;
133	if (asid != cur_asid)
134	continue;
135	}
136
137	/* Note/TODO: Check for multiple matches is not implemented. */
138
139	break;
140	}
141
142	/* Virtual address not found? Then it's a TLB miss. */
143	if (i == SH_N_UTLB_ENTRIES)
144	goto tlb_miss;
145
146	/* Matching address found! Let's see whether it is
147	readable/writable, etc.: */
148	d = lo & SH4_PTEL_D? 1 : 0;
149	pr = (lo & SH4_PTEL_PR_MASK) >> SH4_PTEL_PR_SHIFT;
150
151	*return_paddr = (vaddr & ~mask) \| (lo & mask & 0x1fffffff);
152
153	if (flags & FLAG_INSTR) {
154	/*
155	* Instruction access:
156	*
157	* If a matching entry wasn't found in the ITLB, but in the
158	* UTLB, then copy it to a random place in the ITLB.
159	*/
160	if (i >= 0 && !(flags & FLAG_NOEXCEPTIONS)) {
161	int r = random() % SH_N_ITLB_ENTRIES;
162
163	/* NOTE: Make sure that the old mapping for
164	that itlb entry is invalidated: */
165	cpu->invalidate_translation_caches(cpu,
166	cpu->cd.sh.itlb_hi[r] & ~0xfff, INVALIDATE_VADDR);
167
168	cpu->invalidate_code_translation(cpu,
169	cpu->cd.sh.utlb_lo[i] & ~0xfff, INVALIDATE_PADDR);
170
171	cpu->cd.sh.itlb_hi[r] = cpu->cd.sh.utlb_hi[i];
172	cpu->cd.sh.itlb_lo[r] = cpu->cd.sh.utlb_lo[i];
173	}
174
175	/* Permission checks: */
176	if (cpu->cd.sh.sr & SH_SR_MD)
177	return 1;
178	if (!(pr & 2))
179	goto protection_violation;
180
181	return 1;
182	}
183
184	/* Data access: */
185	if (cpu->cd.sh.sr & SH_SR_MD) {
186	/* Kernel access: */
187	switch (pr) {
188	case 0:
189	case 2: if (wf)
190	goto protection_violation;
191	return 1;
192	case 1:
193	case 3: if (wf && !d)
194	goto initial_write_exception;
195	return 1 + d;
196	}
197	}
198
199	/* User access */
200	switch (pr) {
201	case 0:
202	case 1: goto protection_violation;
203	case 2: if (wf)
204	goto protection_violation;
205	return 1;
206	case 3: if (wf && !d)
207	goto initial_write_exception;
208	return 1 + d;
209	}
210
211
212	tlb_miss:
213	expevt = wf? EXPEVT_TLB_MISS_ST : EXPEVT_TLB_MISS_LD;
214	goto exception;
215
216	protection_violation:
217	expevt = wf? EXPEVT_TLB_PROT_ST : EXPEVT_TLB_PROT_LD;
218	goto exception;
219
220	initial_write_exception:
221	expevt = EXPEVT_TLB_MOD;
222
223
224	exception:
225	if (flags & FLAG_NOEXCEPTIONS) {
226	*return_paddr = 0;
227	return 2;
228	}
229
230	sh_exception(cpu, expevt, 0, vaddr);
231
232	return 0;
233	}
234
235
236	/*
237	* sh_translate_v2p():
238	*
239	* Return values:
240	*
241	* 0 No access to the virtual address.
242	* 1 return_paddr contains the physical address, the page is
243	* available as read-only.
244	* 2 Same as 1, but the page is available as read/write.
245	*/
246	int sh_translate_v2p(struct cpu cpu, uint64_t vaddr64, uint64_t return_paddr,
247	int flags)
248	{
249	int user = cpu->cd.sh.sr & SH_SR_MD? 0 : 1;
250	uint32_t vaddr = vaddr64;
251
252	/* U0/P0: Userspace addresses, or P3: Kernel virtual memory. */
253	if (!(vaddr & 0x80000000) \|\|
254	(vaddr >= 0xc0000000 && vaddr < 0xe0000000)) {
255	/* Address translation turned off? */
256	if (!(cpu->cd.sh.mmucr & SH4_MMUCR_AT)) {
257	/* Then return raw physical address: */
258	*return_paddr = vaddr & 0x1fffffff;
259	return 2;
260	}
261
262	/* Perform translation via the MMU: */
263	return translate_via_mmu(cpu, vaddr, return_paddr, flags);
264	}
265
266	/* Store queue region: */
267	if (vaddr >= 0xe0000000 && vaddr < 0xe4000000) {
268	/* Note/TODO: Take SH4_MMUCR_SQMD into account. */
269	*return_paddr = vaddr;
270	return 2;
271	}
272
273	if (user) {
274	if (flags & FLAG_NOEXCEPTIONS) {
275	*return_paddr = 0;
276	return 2;
277	}
278
279	fatal("Userspace tried to access non-user space memory."
280	" TODO: cause exception! (vaddr=0x%08"PRIx32"\n",
281	(uint32_t) vaddr);
282	exit(1);
283	}
284
285	/* P1,P2: Direct-mapped physical memory. */
286	if (vaddr >= 0x80000000 && vaddr < 0xc0000000) {
287	*return_paddr = vaddr & 0x1fffffff;
288	return 2;
289	}
290
291	if (flags & FLAG_INSTR) {
292	fatal("TODO: instr at 0x%08"PRIx32"\n", (uint32_t)vaddr);
293	exit(1);
294	}
295
296	/* P4: Special registers mapped at 0xf0000000 .. 0xffffffff: */
297	if ((vaddr & 0xf0000000) == 0xf0000000) {
298	*return_paddr = vaddr;
299	return 2;
300	}
301
302	if (flags & FLAG_NOEXCEPTIONS) {
303	*return_paddr = 0;
304	return 2;
305	}
306
307	/* TODO */
308	fatal("Unimplemented SH vaddr 0x%08"PRIx32"\n", (uint32_t)vaddr);
309	exit(1);
310
311	return 0;
312	}
313