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/* immu.c -- Instruction MMU simulation
 
   Copyright (C) 1999 Damjan Lampret, lampret@opencores.org
   Copyright (C) 2008 Embecosm Limited
 
   Contributor Jeremy Bennett <jeremy.bennett@embecosm.com>
 
   This file is part of Or1ksim, the OpenRISC 1000 Architectural Simulator.
 
   This program is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by the Free
   Software Foundation; either version 3 of the License, or (at your option)
   any later version.
 
   This program is distributed in the hope that it will be useful, but WITHOUT
   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
   more details.
 
   You should have received a copy of the GNU General Public License along
   with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
/* This program is commented throughout in a fashion suitable for processing
   with Doxygen. */
 
 
/* Autoconf and/or portability configuration */
#include "config.h"
 
/* System includes */
#include <stdlib.h>
 
/* Package includes */
#include "immu.h"
#include "sim-config.h"
#include "execute.h"
#include "stats.h"
#include "except.h"
#include "spr-dump.h"
#include "misc.h"
#include "sim-cmd.h"
 
 
struct immu *immu_state;
 
/* Insn MMU */
 
static uorreg_t *
immu_find_tlbmr (oraddr_t virtaddr, uorreg_t ** itlbmr_lru, struct immu *immu)
{
  int set;
  int i;
  oraddr_t vpn;
  uorreg_t *itlbmr;
 
  /* Which set to check out? */
  set = IADDR_PAGE (virtaddr) >> immu->pagesize_log2;
  set &= immu->set_mask;
  vpn = virtaddr & immu->vpn_mask;
 
  itlbmr = &cpu_state.sprs[SPR_ITLBMR_BASE (0) + set];
  *itlbmr_lru = itlbmr;
 
  /* Scan all ways and try to find a matching way. */
  /* FIXME: Should this be reversed? */
  for (i = immu->nways; i; i--, itlbmr += (128 * 2))
    {
      if (((*itlbmr & immu->vpn_mask) == vpn) && (*itlbmr & SPR_ITLBMR_V))
        return itlbmr;
    }
 
  return NULL;
}
 
oraddr_t
immu_translate (oraddr_t virtaddr)
{
  int i;
  uorreg_t *itlbmr;
  uorreg_t *itlbtr;
  uorreg_t *itlbmr_lru;
  struct immu *immu = immu_state;
 
  if (!(cpu_state.sprs[SPR_SR] & SPR_SR_IME) ||
      !(cpu_state.sprs[SPR_UPR] & SPR_UPR_IMP))
    {
      insn_ci = (virtaddr >= 0x80000000);
      return virtaddr;
    }
 
  itlbmr = immu_find_tlbmr (virtaddr, &itlbmr_lru, immu);
 
  /* Did we find our tlb entry? */
  if (itlbmr)
    {                           /* Yes, we did. */
      immu_stats.fetch_tlbhit++;
      itlbtr = itlbmr + 128;
 
      /* Set LRUs */
      for (i = 0; i < immu->nways; i++, itlbmr_lru += (128 * 2))
        {
          if (*itlbmr_lru & SPR_ITLBMR_LRU)
            *itlbmr_lru = (*itlbmr_lru & ~SPR_ITLBMR_LRU) |
              ((*itlbmr_lru & SPR_ITLBMR_LRU) - 0x40);
        }
 
      /* This is not necessary `*itlbmr &= ~SPR_ITLBMR_LRU;' since SPR_DTLBMR_LRU
       * is always decremented and the number of sets is always a power of two and
       * as such lru_reload has all bits set that get touched during decrementing
       * SPR_DTLBMR_LRU */
      *itlbmr |= immu->lru_reload;
 
      /* Check if page is cache inhibited */
      insn_ci = *itlbtr & SPR_ITLBTR_CI;
 
      runtime.sim.mem_cycles += immu->hitdelay;
 
      /* Test for page fault */
      if (cpu_state.sprs[SPR_SR] & SPR_SR_SM)
        {
          if (!(*itlbtr & SPR_ITLBTR_SXE))
            except_handle (EXCEPT_IPF, virtaddr);
        }
      else
        {
          if (!(*itlbtr & SPR_ITLBTR_UXE))
            except_handle (EXCEPT_IPF, virtaddr);
        }
 
      return (*itlbtr & SPR_ITLBTR_PPN) | (virtaddr & immu->page_offset_mask);
    }
 
  /* No, we didn't. */
  immu_stats.fetch_tlbmiss++;
#if 0
  for (i = 0; i < immu->nways; i++)
    if (((cpu_state.sprs[SPR_ITLBMR_BASE (i) + set] & SPR_ITLBMR_LRU) >> 6) <
        minlru)
      minway = i;
 
  cpu_state.sprs[SPR_ITLBMR_BASE (minway) + set] &= ~SPR_ITLBMR_VPN;
  cpu_state.sprs[SPR_ITLBMR_BASE (minway) + set] |= vpn << 12;
  for (i = 0; i < immu->nways; i++)
    {
      uorreg_t lru = cpu_state.sprs[SPR_ITLBMR_BASE (i) + set];
      if (lru & SPR_ITLBMR_LRU)
        {
          lru = (lru & ~SPR_ITLBMR_LRU) | ((lru & SPR_ITLBMR_LRU) - 0x40);
          cpu_state.sprs[SPR_ITLBMR_BASE (i) + set] = lru;
        }
    }
  cpu_state.sprs[SPR_ITLBMR_BASE (way) + set] &= ~SPR_ITLBMR_LRU;
  cpu_state.sprs[SPR_ITLBMR_BASE (way) + set] |= (immu->nsets - 1) << 6;
 
  /* 1 to 1 mapping */
  cpu_state.sprs[SPR_ITLBTR_BASE (minway) + set] &= ~SPR_ITLBTR_PPN;
  cpu_state.sprs[SPR_ITLBTR_BASE (minway) + set] |= vpn << 12;
 
  cpu_state.sprs[SPR_ITLBMR_BASE (minway) + set] |= SPR_ITLBMR_V;
#endif
 
  /* if tlb refill implemented in HW */
  /* return ((cpu_state.sprs[SPR_ITLBTR_BASE(minway) + set] & SPR_ITLBTR_PPN) >> 12) * immu->pagesize + (virtaddr % immu->pagesize); */
  runtime.sim.mem_cycles += immu->missdelay;
 
  except_handle (EXCEPT_ITLBMISS, virtaddr);
  return 0;
}
 
/* DESC: try to find EA -> PA transaltion without changing
 *       any of precessor states. if this is not passible gives up
 *       (without triggering exceptions).
 *
 * PRMS: virtaddr  - EA for which to find translation
 *
 * RTRN: 0         - no IMMU, IMMU disabled or ITLB miss
 *       else      - appropriate PA (note it IMMU is not present
 *                   PA === EA)
 */
oraddr_t
peek_into_itlb (oraddr_t virtaddr)
{
  uorreg_t *itlbmr;
  uorreg_t *itlbtr;
  uorreg_t *itlbmr_lru;
  struct immu *immu = immu_state;
 
  if (!(cpu_state.sprs[SPR_SR] & SPR_SR_IME) ||
      !(cpu_state.sprs[SPR_UPR] & SPR_UPR_IMP))
    {
      return (virtaddr);
    }
 
  itlbmr = immu_find_tlbmr (virtaddr, &itlbmr_lru, immu);
 
  /* Did we find our tlb entry? */
  if (itlbmr)
    {                           /* Yes, we did. */
      itlbtr = itlbmr + 128;
 
      /* Test for page fault */
      if (cpu_state.sprs[SPR_SR] & SPR_SR_SM)
        {
          if (!(*itlbtr & SPR_ITLBTR_SXE))
            {
              /* no luck, giving up */
              return (0);
            }
        }
      else
        {
          if (!(*itlbtr & SPR_ITLBTR_UXE))
            {
              /* no luck, giving up */
              return (0);
            }
        }
 
      return (*itlbtr & SPR_ITLBTR_PPN) | (virtaddr & immu->page_offset_mask);
    }
 
  return (0);
}
 
 
/* FIXME: Check validity */
/* First check if virtual address is covered by ITLB and if it is:
    - increment ITLB read hit stats,
    - set 'lru' at this way to immu->ustates - 1 and
      decrement 'lru' of other ways unless they have reached 0,
    - check page access attributes and invoke IMMU page fault exception
      handler if necessary
   and if not:
    - increment ITLB read miss stats
    - find lru way and entry and invoke ITLB miss exception handler
    - set 'lru' with immu->ustates - 1 and decrement 'lru' of other
      ways unless they have reached 0
*/
 
static void
itlb_status (void *dat)
{
  struct immu *immu = dat;
  int set;
  int way;
  int end_set = immu->nsets;
 
  if (!(cpu_state.sprs[SPR_UPR] & SPR_UPR_IMP))
    {
      PRINTF ("IMMU not implemented. Set UPR[IMP].\n");
      return;
    }
 
  if (0 < end_set)
    PRINTF ("\nIMMU: ");
  /* Scan set(s) and way(s). */
  for (set = 0; set < end_set; set++)
    {
      for (way = 0; way < immu->nways; way++)
        {
          PRINTF ("%s\n", dump_spr (SPR_ITLBMR_BASE (way) + set,
                                    cpu_state.sprs[SPR_ITLBMR_BASE (way) +
                                                   set]));
          PRINTF ("%s\n",
                  dump_spr (SPR_ITLBTR_BASE (way) + set,
                            cpu_state.sprs[SPR_ITLBTR_BASE (way) + set]));
        }
    }
  if (0 < end_set)
    PRINTF ("\n");
}
 
/*---------------------------------------------------[ IMMU configuration ]---*/
 
/*---------------------------------------------------------------------------*/
/*!Enable or disable the IMMU
 
   Set the corresponding field in the UPR
 
   @param[in] val  The value to use
   @param[in] dat  The config data structure                                 */
/*---------------------------------------------------------------------------*/
static void
immu_enabled (union param_val val, void *dat)
{
  struct immu *immu = dat;
 
  if (val.int_val)
    {
      cpu_state.sprs[SPR_UPR] |= SPR_UPR_IMP;
    }
  else
    {
      cpu_state.sprs[SPR_UPR] &= ~SPR_UPR_IMP;
    }
 
  immu->enabled = val.int_val;
}
 
 
/*---------------------------------------------------------------------------*/
/*!Set the number of DMMU sets
 
   Value must be a power of 2 <= 256. Ignore any other values with a
   warning. Set the corresponding IMMU configuration flags.
 
   @param[in] val  The value to use
   @param[in] dat  The config data structure                                 */
/*---------------------------------------------------------------------------*/
static void
immu_nsets (union param_val  val,
            void            *dat)
{
  struct immu *immu = dat;
 
  if (is_power2 (val.int_val) && (val.int_val <= 128))
    {
      int  set_bits = log2_int (val.int_val);
 
      immu->nsets = val.int_val;
 
      cpu_state.sprs[SPR_IMMUCFGR] &= ~SPR_IMMUCFGR_NTS;
      cpu_state.sprs[SPR_IMMUCFGR] |= set_bits << SPR_IMMUCFGR_NTS_OFF;
    }
  else
    {
      fprintf (stderr, "Warning IMMU nsets not a power of 2 <= 128: ignored\n");
    }
}       /* immu_nsets() */
 
 
/*---------------------------------------------------------------------------*/
/*!Set the number of IMMU ways
 
   Value must be in the range 1-4. Ignore other values with a warning.  Set
   the corresponding IMMU configuration flags.
 
   @param[in] val  The value to use
   @param[in] dat  The config data structure                                 */
/*---------------------------------------------------------------------------*/
static void
immu_nways (union param_val  val,
            void            *dat)
{
  struct immu *immu = dat;
 
  if (val.int_val >= 1 && val.int_val <= 4)
    {
      int  way_bits = val.int_val - 1;
 
      immu->nways = val.int_val;
 
      cpu_state.sprs[SPR_IMMUCFGR] &= ~SPR_IMMUCFGR_NTW;
      cpu_state.sprs[SPR_IMMUCFGR] |= way_bits << SPR_IMMUCFGR_NTW_OFF;
    }
  else
    {
      fprintf (stderr, "Warning IMMU nways not in range 1-4: ignored\n");
    }
}       /* immu_nways() */
 
 
/*---------------------------------------------------------------------------*/
/*!Set the IMMU page size
 
   Value must be a power of 2. Ignore other values with a warning
 
   @param[in] val  The value to use
   @param[in] dat  The config data structure                                 */
/*---------------------------------------------------------------------------*/
static void
immu_pagesize (union param_val  val,
               void            *dat)
{
  struct immu *immu = dat;
 
  if (is_power2 (val.int_val))
    {
      immu->pagesize = val.int_val;
    }
  else
    {
      fprintf (stderr, "Warning IMMU page size must be power of 2: ignored\n");
    }
}       /* immu_pagesize() */
 
 
/*---------------------------------------------------------------------------*/
/*!Set the IMMU entry size
 
   Value must be a power of 2. Ignore other values with a warning
 
   @param[in] val  The value to use
   @param[in] dat  The config data structure                                 */
/*---------------------------------------------------------------------------*/
static void
immu_entrysize (union param_val  val,
                void            *dat)
{
  struct immu *immu = dat;
 
  if (is_power2 (val.int_val))
    {
      immu->entrysize = val.int_val;
    }
  else
    {
      fprintf (stderr, "Warning IMMU entry size must be power of 2: ignored\n");
    }
}       /* immu_entrysize() */
 
 
/*---------------------------------------------------------------------------*/
/*!Set the number of IMMU usage states
 
   Value must be 2, 3 or 4. Ignore other values with a warning
 
   @param[in] val  The value to use
   @param[in] dat  The config data structure                                 */
/*---------------------------------------------------------------------------*/
static void
immu_ustates (union param_val  val,
              void            *dat)
{
  struct immu *immu = dat;
 
  if ((val.int_val >= 2) && (val.int_val <= 4))
    {
      immu->ustates = val.int_val;
    }
  else
    {
      fprintf (stderr, "Warning number of IMMU usage states must be 2, 3 or 4:"
               "ignored\n");
    }
}       /* immu_ustates() */
 
 
static void
immu_missdelay (union param_val val, void *dat)
{
  struct immu *immu = dat;
 
  immu->missdelay = val.int_val;
}
 
static void
immu_hitdelay (union param_val val, void *dat)
{
  struct immu *immu = dat;
 
  immu->hitdelay = val.int_val;
}
 
/*---------------------------------------------------------------------------*/
/*!Initialize a new DMMU configuration
 
   ALL parameters are set explicitly to default values.                      */
/*---------------------------------------------------------------------------*/
static void *
immu_start_sec ()
{
  struct immu *immu;
  int          set_bits;
  int          way_bits;
 
  if (NULL == (immu = malloc (sizeof (struct immu))))
    {
      fprintf (stderr, "OOM\n");
      exit (1);
    }
 
  immu->enabled   = 0;
  immu->nsets     = 1;
  immu->nways     = 1;
  immu->pagesize  = 8192;
  immu->entrysize = 1;          /* Not currently used */
  immu->ustates   = 2;
  immu->hitdelay  = 1;
  immu->missdelay = 1;
 
  if (immu->enabled)
    {
      cpu_state.sprs[SPR_UPR] |= SPR_UPR_IMP;
    }
  else
    {
      cpu_state.sprs[SPR_UPR] &= ~SPR_UPR_IMP;
    }
 
  set_bits = log2_int (immu->nsets);
  cpu_state.sprs[SPR_IMMUCFGR] &= ~SPR_IMMUCFGR_NTS;
  cpu_state.sprs[SPR_IMMUCFGR] |= set_bits << SPR_IMMUCFGR_NTS_OFF;
 
  way_bits = immu->nways - 1;
  cpu_state.sprs[SPR_IMMUCFGR] &= ~SPR_IMMUCFGR_NTW;
  cpu_state.sprs[SPR_IMMUCFGR] |= way_bits << SPR_IMMUCFGR_NTW_OFF;
 
  immu_state = immu;
  return immu;
 
}       /* immu_start_sec() */
 
 
static void
immu_end_sec (void *dat)
{
  struct immu *immu = dat;
 
  /* Precalculate some values for use during address translation */
  immu->pagesize_log2 = log2_int (immu->pagesize);
  immu->page_offset_mask = immu->pagesize - 1;
  immu->page_mask = ~immu->page_offset_mask;
  immu->vpn_mask = ~((immu->pagesize * immu->nsets) - 1);
  immu->set_mask = immu->nsets - 1;
  immu->lru_reload = (immu->set_mask << 6) & SPR_ITLBMR_LRU;
 
  if (immu->enabled)
    {
      PRINTF ("Insn MMU %dKB: %d ways, %d sets, entry size %d bytes\n",
              immu->nsets * immu->entrysize * immu->nways / 1024, immu->nways,
              immu->nsets, immu->entrysize);
      reg_sim_stat (itlb_status, immu);
    }
}
 
void
reg_immu_sec (void)
{
  struct config_section *sec = reg_config_sec ("immu", immu_start_sec,
                                               immu_end_sec);
 
  reg_config_param (sec, "enabled", paramt_int, immu_enabled);
  reg_config_param (sec, "nsets", paramt_int, immu_nsets);
  reg_config_param (sec, "nways", paramt_int, immu_nways);
  reg_config_param (sec, "pagesize", paramt_int, immu_pagesize);
  reg_config_param (sec, "entrysize", paramt_int, immu_entrysize);
  reg_config_param (sec, "ustates", paramt_int, immu_ustates);
  reg_config_param (sec, "missdelay", paramt_int, immu_missdelay);
  reg_config_param (sec, "hitdelay", paramt_int, immu_hitdelay);
}

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[/] [openrisc/] [trunk/] [or1ksim/] [mmu/] [immu.c] - Blame information for rev 199

Line No.	Rev	Author	Line
1	19	jeremybenn	`/* immu.c -- Instruction MMU simulation`
2
3			`Copyright (C) 1999 Damjan Lampret, lampret@opencores.org`
4			`Copyright (C) 2008 Embecosm Limited`
5
6			`Contributor Jeremy Bennett <jeremy.bennett@embecosm.com>`
7
8			`This file is part of Or1ksim, the OpenRISC 1000 Architectural Simulator.`
9
10			`This program is free software; you can redistribute it and/or modify it`
11			`under the terms of the GNU General Public License as published by the Free`
12			`Software Foundation; either version 3 of the License, or (at your option)`
13			`any later version.`
14
15			`This program is distributed in the hope that it will be useful, but WITHOUT`
16			`ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or`
17			`FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for`
18			`more details.`
19
20			`You should have received a copy of the GNU General Public License along`
21			`with this program. If not, see <http://www.gnu.org/licenses/>. */`
22
23			`/* This program is commented throughout in a fashion suitable for processing`
24			`with Doxygen. */`
25
26
27			`/* Autoconf and/or portability configuration */`
28			`#include "config.h"`
29
30			`/* System includes */`
31			`#include <stdlib.h>`
32
33			`/* Package includes */`
34			`#include "immu.h"`
35			`#include "sim-config.h"`
36			`#include "execute.h"`
37			`#include "stats.h"`
38			`#include "except.h"`
39			`#include "spr-dump.h"`
40			`#include "misc.h"`
41			`#include "sim-cmd.h"`
42
43
44			`struct immu *immu_state;`
45
46			`/* Insn MMU */`
47
48			`static uorreg_t *`
49			`immu_find_tlbmr (oraddr_t virtaddr, uorreg_t ** itlbmr_lru, struct immu *immu)`
50			`{`
51			`int set;`
52			`int i;`
53			`oraddr_t vpn;`
54			`uorreg_t *itlbmr;`
55
56			`/* Which set to check out? */`
57			`set = IADDR_PAGE (virtaddr) >> immu->pagesize_log2;`
58			`set &= immu->set_mask;`
59			`vpn = virtaddr & immu->vpn_mask;`
60
61			`itlbmr = &cpu_state.sprs[SPR_ITLBMR_BASE (0) + set];`
62			`*itlbmr_lru = itlbmr;`
63
64			`/* Scan all ways and try to find a matching way. */`
65			`/* FIXME: Should this be reversed? */`
66			`for (i = immu->nways; i; i--, itlbmr += (128 * 2))`
67			`{`
68			`if (((itlbmr & immu->vpn_mask) == vpn) && (itlbmr & SPR_ITLBMR_V))`
69			`return itlbmr;`
70			`}`
71
72			`return NULL;`
73			`}`
74
75			`oraddr_t`
76			`immu_translate (oraddr_t virtaddr)`
77			`{`
78			`int i;`
79			`uorreg_t *itlbmr;`
80			`uorreg_t *itlbtr;`
81			`uorreg_t *itlbmr_lru;`
82			`struct immu *immu = immu_state;`
83
84			`if (!(cpu_state.sprs[SPR_SR] & SPR_SR_IME) \|\|`
85			`!(cpu_state.sprs[SPR_UPR] & SPR_UPR_IMP))`
86			`{`
87			`insn_ci = (virtaddr >= 0x80000000);`
88			`return virtaddr;`
89			`}`
90
91			`itlbmr = immu_find_tlbmr (virtaddr, &itlbmr_lru, immu);`
92
93			`/* Did we find our tlb entry? */`
94			`if (itlbmr)`
95			`{ /* Yes, we did. */`
96			`immu_stats.fetch_tlbhit++;`
97			`itlbtr = itlbmr + 128;`
98
99			`/* Set LRUs */`
100			`for (i = 0; i < immu->nways; i++, itlbmr_lru += (128 * 2))`
101			`{`
102			`if (*itlbmr_lru & SPR_ITLBMR_LRU)`
103			`itlbmr_lru = (itlbmr_lru & ~SPR_ITLBMR_LRU) \|`
104			`((*itlbmr_lru & SPR_ITLBMR_LRU) - 0x40);`
105			`}`
106
107			/* This is not necessary `*itlbmr &= ~SPR_ITLBMR_LRU;' since SPR_DTLBMR_LRU
108			`* is always decremented and the number of sets is always a power of two and`
109			`* as such lru_reload has all bits set that get touched during decrementing`
110			`* SPR_DTLBMR_LRU */`
111			`*itlbmr \|= immu->lru_reload;`
112
113			`/* Check if page is cache inhibited */`
114			`insn_ci = *itlbtr & SPR_ITLBTR_CI;`
115
116			`runtime.sim.mem_cycles += immu->hitdelay;`
117
118			`/* Test for page fault */`
119			`if (cpu_state.sprs[SPR_SR] & SPR_SR_SM)`
120			`{`
121			`if (!(*itlbtr & SPR_ITLBTR_SXE))`
122			`except_handle (EXCEPT_IPF, virtaddr);`
123			`}`
124			`else`
125			`{`
126			`if (!(*itlbtr & SPR_ITLBTR_UXE))`
127			`except_handle (EXCEPT_IPF, virtaddr);`
128			`}`
129
130			`return (*itlbtr & SPR_ITLBTR_PPN) \| (virtaddr & immu->page_offset_mask);`
131			`}`
132
133			`/* No, we didn't. */`
134			`immu_stats.fetch_tlbmiss++;`
135			`#if 0`
136			`for (i = 0; i < immu->nways; i++)`
137			`if (((cpu_state.sprs[SPR_ITLBMR_BASE (i) + set] & SPR_ITLBMR_LRU) >> 6) <`
138			`minlru)`
139			`minway = i;`
140
141			`cpu_state.sprs[SPR_ITLBMR_BASE (minway) + set] &= ~SPR_ITLBMR_VPN;`
142			`cpu_state.sprs[SPR_ITLBMR_BASE (minway) + set] \|= vpn << 12;`
143			`for (i = 0; i < immu->nways; i++)`
144			`{`
145			`uorreg_t lru = cpu_state.sprs[SPR_ITLBMR_BASE (i) + set];`
146			`if (lru & SPR_ITLBMR_LRU)`
147			`{`
148			`lru = (lru & ~SPR_ITLBMR_LRU) \| ((lru & SPR_ITLBMR_LRU) - 0x40);`
149			`cpu_state.sprs[SPR_ITLBMR_BASE (i) + set] = lru;`
150			`}`
151			`}`
152			`cpu_state.sprs[SPR_ITLBMR_BASE (way) + set] &= ~SPR_ITLBMR_LRU;`
153			`cpu_state.sprs[SPR_ITLBMR_BASE (way) + set] \|= (immu->nsets - 1) << 6;`
154
155			`/* 1 to 1 mapping */`
156			`cpu_state.sprs[SPR_ITLBTR_BASE (minway) + set] &= ~SPR_ITLBTR_PPN;`
157			`cpu_state.sprs[SPR_ITLBTR_BASE (minway) + set] \|= vpn << 12;`
158
159			`cpu_state.sprs[SPR_ITLBMR_BASE (minway) + set] \|= SPR_ITLBMR_V;`
160			`#endif`
161
162			`/* if tlb refill implemented in HW */`
163			`/* return ((cpu_state.sprs[SPR_ITLBTR_BASE(minway) + set] & SPR_ITLBTR_PPN) >> 12) * immu->pagesize + (virtaddr % immu->pagesize); */`
164			`runtime.sim.mem_cycles += immu->missdelay;`
165
166			`except_handle (EXCEPT_ITLBMISS, virtaddr);`
167			`return 0;`
168			`}`
169
170			`/* DESC: try to find EA -> PA transaltion without changing`
171			`* any of precessor states. if this is not passible gives up`
172			`* (without triggering exceptions).`
173			`*`
174			`* PRMS: virtaddr - EA for which to find translation`
175			`*`
176			`* RTRN: 0 - no IMMU, IMMU disabled or ITLB miss`
177			`* else - appropriate PA (note it IMMU is not present`
178			`* PA === EA)`
179			`*/`
180			`oraddr_t`
181			`peek_into_itlb (oraddr_t virtaddr)`
182			`{`
183			`uorreg_t *itlbmr;`
184			`uorreg_t *itlbtr;`
185			`uorreg_t *itlbmr_lru;`
186			`struct immu *immu = immu_state;`
187
188			`if (!(cpu_state.sprs[SPR_SR] & SPR_SR_IME) \|\|`
189			`!(cpu_state.sprs[SPR_UPR] & SPR_UPR_IMP))`
190			`{`
191			`return (virtaddr);`
192			`}`
193
194			`itlbmr = immu_find_tlbmr (virtaddr, &itlbmr_lru, immu);`
195
196			`/* Did we find our tlb entry? */`
197			`if (itlbmr)`
198			`{ /* Yes, we did. */`
199			`itlbtr = itlbmr + 128;`
200
201			`/* Test for page fault */`
202			`if (cpu_state.sprs[SPR_SR] & SPR_SR_SM)`
203			`{`
204			`if (!(*itlbtr & SPR_ITLBTR_SXE))`
205			`{`
206			`/* no luck, giving up */`
207			`return (0);`
208			`}`
209			`}`
210			`else`
211			`{`
212			`if (!(*itlbtr & SPR_ITLBTR_UXE))`
213			`{`
214			`/* no luck, giving up */`
215			`return (0);`
216			`}`
217			`}`
218
219			`return (*itlbtr & SPR_ITLBTR_PPN) \| (virtaddr & immu->page_offset_mask);`
220			`}`
221
222			`return (0);`
223			`}`
224
225
226			`/* FIXME: Check validity */`
227			`/* First check if virtual address is covered by ITLB and if it is:`
228			`- increment ITLB read hit stats,`
229			`- set 'lru' at this way to immu->ustates - 1 and`
230			`decrement 'lru' of other ways unless they have reached 0,`
231			`- check page access attributes and invoke IMMU page fault exception`
232			`handler if necessary`
233			`and if not:`
234			`- increment ITLB read miss stats`
235			`- find lru way and entry and invoke ITLB miss exception handler`
236			`- set 'lru' with immu->ustates - 1 and decrement 'lru' of other`
237			`ways unless they have reached 0`
238			`*/`
239
240			`static void`
241			`itlb_status (void *dat)`
242			`{`
243			`struct immu *immu = dat;`
244			`int set;`
245			`int way;`
246			`int end_set = immu->nsets;`
247
248			`if (!(cpu_state.sprs[SPR_UPR] & SPR_UPR_IMP))`
249			`{`
250			`PRINTF ("IMMU not implemented. Set UPR[IMP].\n");`
251			`return;`
252			`}`
253
254			`if (0 < end_set)`
255			`PRINTF ("\nIMMU: ");`
256			`/* Scan set(s) and way(s). */`
257			`for (set = 0; set < end_set; set++)`
258			`{`
259			`for (way = 0; way < immu->nways; way++)`
260			`{`
261			`PRINTF ("%s\n", dump_spr (SPR_ITLBMR_BASE (way) + set,`
262			`cpu_state.sprs[SPR_ITLBMR_BASE (way) +`
263			`set]));`
264			`PRINTF ("%s\n",`
265			`dump_spr (SPR_ITLBTR_BASE (way) + set,`
266			`cpu_state.sprs[SPR_ITLBTR_BASE (way) + set]));`
267			`}`
268			`}`
269			`if (0 < end_set)`
270			`PRINTF ("\n");`
271			`}`
272
273			`/---------------------------------------------------[ IMMU configuration ]---/`
274
275			`/---------------------------------------------------------------------------/`
276			`/*!Enable or disable the IMMU`
277
278			`Set the corresponding field in the UPR`
279
280			`@param[in] val The value to use`
281			`@param[in] dat The config data structure */`
282			`/---------------------------------------------------------------------------/`
283			`static void`
284			`immu_enabled (union param_val val, void *dat)`
285			`{`
286			`struct immu *immu = dat;`
287
288			`if (val.int_val)`
289			`{`
290			`cpu_state.sprs[SPR_UPR] \|= SPR_UPR_IMP;`
291			`}`
292			`else`
293			`{`
294			`cpu_state.sprs[SPR_UPR] &= ~SPR_UPR_IMP;`
295			`}`
296
297			`immu->enabled = val.int_val;`
298			`}`
299
300
301			`/---------------------------------------------------------------------------/`
302			`/*!Set the number of DMMU sets`
303
304			`Value must be a power of 2 <= 256. Ignore any other values with a`
305			`warning. Set the corresponding IMMU configuration flags.`
306
307			`@param[in] val The value to use`
308			`@param[in] dat The config data structure */`
309			`/---------------------------------------------------------------------------/`
310			`static void`
311			`immu_nsets (union param_val val,`
312			`void *dat)`
313			`{`
314			`struct immu *immu = dat;`
315
316			`if (is_power2 (val.int_val) && (val.int_val <= 128))`
317			`{`
318			`int set_bits = log2_int (val.int_val);`
319
320			`immu->nsets = val.int_val;`
321
322			`cpu_state.sprs[SPR_IMMUCFGR] &= ~SPR_IMMUCFGR_NTS;`
323			`cpu_state.sprs[SPR_IMMUCFGR] \|= set_bits << SPR_IMMUCFGR_NTS_OFF;`
324			`}`
325			`else`
326			`{`
327			`fprintf (stderr, "Warning IMMU nsets not a power of 2 <= 128: ignored\n");`
328			`}`
329			`} /* immu_nsets() */`
330
331
332			`/---------------------------------------------------------------------------/`
333			`/*!Set the number of IMMU ways`
334
335			`Value must be in the range 1-4. Ignore other values with a warning. Set`
336			`the corresponding IMMU configuration flags.`
337
338			`@param[in] val The value to use`
339			`@param[in] dat The config data structure */`
340			`/---------------------------------------------------------------------------/`
341			`static void`
342			`immu_nways (union param_val val,`
343			`void *dat)`
344			`{`
345			`struct immu *immu = dat;`
346
347			`if (val.int_val >= 1 && val.int_val <= 4)`
348			`{`
349			`int way_bits = val.int_val - 1;`
350
351			`immu->nways = val.int_val;`
352
353			`cpu_state.sprs[SPR_IMMUCFGR] &= ~SPR_IMMUCFGR_NTW;`
354			`cpu_state.sprs[SPR_IMMUCFGR] \|= way_bits << SPR_IMMUCFGR_NTW_OFF;`
355			`}`
356			`else`
357			`{`
358			`fprintf (stderr, "Warning IMMU nways not in range 1-4: ignored\n");`
359			`}`
360			`} /* immu_nways() */`
361
362
363			`/---------------------------------------------------------------------------/`
364			`/*!Set the IMMU page size`
365
366			`Value must be a power of 2. Ignore other values with a warning`
367
368			`@param[in] val The value to use`
369			`@param[in] dat The config data structure */`
370			`/---------------------------------------------------------------------------/`
371			`static void`
372			`immu_pagesize (union param_val val,`
373			`void *dat)`
374			`{`
375			`struct immu *immu = dat;`
376
377			`if (is_power2 (val.int_val))`
378			`{`
379			`immu->pagesize = val.int_val;`
380			`}`
381			`else`
382			`{`
383			`fprintf (stderr, "Warning IMMU page size must be power of 2: ignored\n");`
384			`}`
385			`} /* immu_pagesize() */`
386
387
388			`/---------------------------------------------------------------------------/`
389			`/*!Set the IMMU entry size`
390
391			`Value must be a power of 2. Ignore other values with a warning`
392
393			`@param[in] val The value to use`
394			`@param[in] dat The config data structure */`
395			`/---------------------------------------------------------------------------/`
396			`static void`
397			`immu_entrysize (union param_val val,`
398			`void *dat)`
399			`{`
400			`struct immu *immu = dat;`
401
402			`if (is_power2 (val.int_val))`
403			`{`
404			`immu->entrysize = val.int_val;`
405			`}`
406			`else`
407			`{`
408			`fprintf (stderr, "Warning IMMU entry size must be power of 2: ignored\n");`
409			`}`
410			`} /* immu_entrysize() */`
411
412
413			`/---------------------------------------------------------------------------/`
414			`/*!Set the number of IMMU usage states`
415
416			`Value must be 2, 3 or 4. Ignore other values with a warning`
417
418			`@param[in] val The value to use`
419			`@param[in] dat The config data structure */`
420			`/---------------------------------------------------------------------------/`
421			`static void`
422			`immu_ustates (union param_val val,`
423			`void *dat)`
424			`{`
425			`struct immu *immu = dat;`
426
427			`if ((val.int_val >= 2) && (val.int_val <= 4))`
428			`{`
429			`immu->ustates = val.int_val;`
430			`}`
431			`else`
432			`{`
433			`fprintf (stderr, "Warning number of IMMU usage states must be 2, 3 or 4:"`
434			`"ignored\n");`
435			`}`
436			`} /* immu_ustates() */`
437
438
439			`static void`
440			`immu_missdelay (union param_val val, void *dat)`
441			`{`
442			`struct immu *immu = dat;`
443
444			`immu->missdelay = val.int_val;`
445			`}`
446
447			`static void`
448			`immu_hitdelay (union param_val val, void *dat)`
449			`{`
450			`struct immu *immu = dat;`
451
452			`immu->hitdelay = val.int_val;`
453			`}`
454
455			`/---------------------------------------------------------------------------/`
456			`/*!Initialize a new DMMU configuration`
457
458			`ALL parameters are set explicitly to default values. */`
459			`/---------------------------------------------------------------------------/`
460			`static void *`
461			`immu_start_sec ()`
462			`{`
463			`struct immu *immu;`
464			`int set_bits;`
465			`int way_bits;`
466
467			`if (NULL == (immu = malloc (sizeof (struct immu))))`
468			`{`
469			`fprintf (stderr, "OOM\n");`
470			`exit (1);`
471			`}`
472
473			`immu->enabled = 0;`
474			`immu->nsets = 1;`
475			`immu->nways = 1;`
476			`immu->pagesize = 8192;`
477			`immu->entrysize = 1; /* Not currently used */`
478			`immu->ustates = 2;`
479			`immu->hitdelay = 1;`
480			`immu->missdelay = 1;`
481
482			`if (immu->enabled)`
483			`{`
484			`cpu_state.sprs[SPR_UPR] \|= SPR_UPR_IMP;`
485			`}`
486			`else`
487			`{`
488			`cpu_state.sprs[SPR_UPR] &= ~SPR_UPR_IMP;`
489			`}`
490
491			`set_bits = log2_int (immu->nsets);`
492			`cpu_state.sprs[SPR_IMMUCFGR] &= ~SPR_IMMUCFGR_NTS;`
493			`cpu_state.sprs[SPR_IMMUCFGR] \|= set_bits << SPR_IMMUCFGR_NTS_OFF;`
494
495			`way_bits = immu->nways - 1;`
496			`cpu_state.sprs[SPR_IMMUCFGR] &= ~SPR_IMMUCFGR_NTW;`
497			`cpu_state.sprs[SPR_IMMUCFGR] \|= way_bits << SPR_IMMUCFGR_NTW_OFF;`
498
499			`immu_state = immu;`
500			`return immu;`
501
502			`} /* immu_start_sec() */`
503
504
505			`static void`
506			`immu_end_sec (void *dat)`
507			`{`
508			`struct immu *immu = dat;`
509
510			`/* Precalculate some values for use during address translation */`
511			`immu->pagesize_log2 = log2_int (immu->pagesize);`
512			`immu->page_offset_mask = immu->pagesize - 1;`
513			`immu->page_mask = ~immu->page_offset_mask;`
514			`immu->vpn_mask = ~((immu->pagesize * immu->nsets) - 1);`
515			`immu->set_mask = immu->nsets - 1;`
516			`immu->lru_reload = (immu->set_mask << 6) & SPR_ITLBMR_LRU;`
517
518			`if (immu->enabled)`
519			`{`
520			`PRINTF ("Insn MMU %dKB: %d ways, %d sets, entry size %d bytes\n",`
521			`immu->nsets * immu->entrysize * immu->nways / 1024, immu->nways,`
522			`immu->nsets, immu->entrysize);`
523			`reg_sim_stat (itlb_status, immu);`
524			`}`
525			`}`
526
527			`void`
528			`reg_immu_sec (void)`
529			`{`
530			`struct config_section *sec = reg_config_sec ("immu", immu_start_sec,`
531			`immu_end_sec);`
532
533			`reg_config_param (sec, "enabled", paramt_int, immu_enabled);`
534			`reg_config_param (sec, "nsets", paramt_int, immu_nsets);`
535			`reg_config_param (sec, "nways", paramt_int, immu_nways);`
536			`reg_config_param (sec, "pagesize", paramt_int, immu_pagesize);`
537			`reg_config_param (sec, "entrysize", paramt_int, immu_entrysize);`
538			`reg_config_param (sec, "ustates", paramt_int, immu_ustates);`
539			`reg_config_param (sec, "missdelay", paramt_int, immu_missdelay);`
540			`reg_config_param (sec, "hitdelay", paramt_int, immu_hitdelay);`
541			`}`