/* Caching code. Typically used by remote back ends for
caching remote memory.
- Copyright 1992, 1993, 1995 Free Software Foundation, Inc.
+ Copyright 1992-1993, 1995, 1998-1999 Free Software Foundation, Inc.
This file is part of GDB.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+ Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
#include "defs.h"
#include "dcache.h"
#include "gdbcmd.h"
-#include <string.h>
-
+#include "gdb_string.h"
+#include "gdbcore.h"
/*
The data cache could lead to incorrect results because it doesn't know
read the cache line in the first place.
- */
+ */
/* This value regulates the number of cache blocks stored.
line, and reduce memory requirements, but increase the risk
of a line not being in memory */
-#define DCACHE_SIZE 64
+#define DCACHE_SIZE 64
/* This value regulates the size of a cache line. Smaller values
reduce the time taken to read a single byte, but reduce overall
throughput. */
-#define LINE_SIZE_POWER (5)
+#define LINE_SIZE_POWER (5)
#define LINE_SIZE (1 << LINE_SIZE_POWER)
/* Each cache block holds LINE_SIZE bytes of data
starting at a multiple-of-LINE_SIZE address. */
-#define LINE_SIZE_MASK ((LINE_SIZE - 1))
+#define LINE_SIZE_MASK ((LINE_SIZE - 1))
#define XFORM(x) ((x) & LINE_SIZE_MASK)
#define MASK(x) ((x) & ~LINE_SIZE_MASK)
-#define ENTRY_BAD 0 /* data at this byte is wrong */
-#define ENTRY_DIRTY 1 /* data at this byte needs to be written back */
-#define ENTRY_OK 2 /* data at this byte is same as in memory */
+#define ENTRY_BAD 0 /* data at this byte is wrong */
+#define ENTRY_DIRTY 1 /* data at this byte needs to be written back */
+#define ENTRY_OK 2 /* data at this byte is same as in memory */
struct dcache_block
-{
- struct dcache_block *p; /* next in list */
- unsigned int addr; /* Address for which data is recorded. */
- unsigned char data[LINE_SIZE]; /* bytes at given address */
- unsigned char state[LINE_SIZE]; /* what state the data is in */
+ {
+ struct dcache_block *p; /* next in list */
+ CORE_ADDR addr; /* Address for which data is recorded. */
+ char data[LINE_SIZE]; /* bytes at given address */
+ unsigned char state[LINE_SIZE]; /* what state the data is in */
- /* whether anything in state is dirty - used to speed up the
- dirty scan. */
- int anydirty;
+ /* whether anything in state is dirty - used to speed up the
+ dirty scan. */
+ int anydirty;
- int refs;
-};
+ int refs;
+ };
-struct dcache_struct
-{
- /* Function to actually read the target memory. */
- memxferfunc read_memory;
+struct dcache_struct
+ {
+ /* Function to actually read the target memory. */
+ memxferfunc read_memory;
+
+ /* Function to actually write the target memory */
+ memxferfunc write_memory;
+
+ /* free list */
+ struct dcache_block *free_head;
+ struct dcache_block *free_tail;
+
+ /* in use list */
+ struct dcache_block *valid_head;
+ struct dcache_block *valid_tail;
+
+ /* The cache itself. */
+ struct dcache_block *the_cache;
+
+ /* potentially, if the cache was enabled, and then turned off, and
+ then turned on again, the stuff in it could be stale, so this is
+ used to mark it */
+ int cache_has_stuff;
+ };
- /* Function to actually write the target memory */
- memxferfunc write_memory;
+static int dcache_poke_byte (DCACHE * dcache, CORE_ADDR addr, char *ptr);
- /* free list */
- struct dcache_block *free_head;
- struct dcache_block *free_tail;
+static int dcache_peek_byte (DCACHE * dcache, CORE_ADDR addr, char *ptr);
- /* in use list */
- struct dcache_block *valid_head;
- struct dcache_block *valid_tail;
+static struct dcache_block *dcache_hit (DCACHE * dcache, CORE_ADDR addr);
- /* The cache itself. */
- struct dcache_block *the_cache;
+static int dcache_write_line (DCACHE * dcache, struct dcache_block *db);
- /* potentially, if the cache was enabled, and then turned off, and
- then turned on again, the stuff in it could be stale, so this is
- used to mark it */
- int cache_has_stuff;
-} ;
+static struct dcache_block *dcache_alloc (DCACHE * dcache);
-int remote_dcache = 1;
+static int dcache_writeback (DCACHE * dcache);
-DCACHE *last_cache; /* Used by info dcache */
+static void dcache_info (char *exp, int tty);
+void _initialize_dcache (void);
+
+static int dcache_enabled_p = 0;
+
+DCACHE *last_cache; /* Used by info dcache */
/* Free all the data cache blocks, thus discarding all cached data. */
/* If addr is present in the dcache, return the address of the block
containing it. */
-static
-struct dcache_block *
+
+static struct dcache_block *
dcache_hit (dcache, addr)
DCACHE *dcache;
- unsigned int addr;
+ CORE_ADDR addr;
{
register struct dcache_block *db;
while (db)
{
- if (MASK(addr) == db->addr)
+ if (MASK (addr) == db->addr)
{
db->refs++;
return db;
if (db->state[s] == ENTRY_DIRTY)
{
int len = 0;
- for (e = s ; e < LINE_SIZE; e++, len++)
+ for (e = s; e < LINE_SIZE; e++, len++)
if (db->state[e] != ENTRY_DIRTY)
+ break;
+ {
+ /* all bytes from s..s+len-1 need to
+ be written out */
+ int done = 0;
+ while (done < len)
{
- /* all bytes from s..s+len-1 need to
- be written out */
- int done = 0;
- while (done < len) {
- int t = dcache->write_memory (db->addr + s + done,
- db->data + s + done,
- len - done);
- if (t == 0)
- return 0;
- done += t;
- }
- memset (db->state + s, ENTRY_OK, len);
- s = e;
- break;
+ int t = dcache->write_memory (db->addr + s + done,
+ db->data + s + done,
+ len - done);
+ if (t == 0)
+ return 0;
+ done += t;
}
+ memset (db->state + s, ENTRY_OK, len);
+ s = e;
+ }
}
}
db->anydirty = 0;
prevents errors from creeping in if a memory retrieval is
interrupted (which used to put garbage blocks in the valid
list...). */
-static
-struct dcache_block *
+
+static struct dcache_block *
dcache_alloc (dcache)
DCACHE *dcache;
{
register struct dcache_block *db;
- if (remote_dcache == 0)
+ if (dcache_enabled_p == 0)
abort ();
/* Take something from the free list */
- if (db = dcache->free_head)
+ db = dcache->free_head;
+ if (db)
{
dcache->free_head = db->p;
}
-
- if (!db)
+ else
{
- /* Nothing left on free list, so grab on from the valid list */
+ /* Nothing left on free list, so grab one from the valid list */
db = dcache->valid_head;
dcache->valid_head = db->p;
Returns 0 on error. */
-int
+static int
dcache_peek_byte (dcache, addr, ptr)
DCACHE *dcache;
CORE_ADDR addr;
- unsigned char *ptr;
+ char *ptr;
{
register struct dcache_block *db = dcache_hit (dcache, addr);
- int ok=1;
+ int ok = 1;
int done = 0;
if (db == 0
|| db->state[XFORM (addr)] == ENTRY_BAD)
{
dcache_write_line (dcache, db);
}
- else
- db = dcache_alloc (dcache);
+ else
+ db = dcache_alloc (dcache);
immediate_quit++;
- db->addr = MASK (addr);
- while (done < LINE_SIZE)
+ db->addr = MASK (addr);
+ while (done < LINE_SIZE)
{
int try =
- (*dcache->read_memory)
- (db->addr + done,
- (unsigned char *) db->data + done,
- LINE_SIZE - done);
+ (*dcache->read_memory)
+ (db->addr + done,
+ db->data + done,
+ LINE_SIZE - done);
if (try == 0)
return 0;
done += try;
}
immediate_quit--;
-
+
memset (db->state, ENTRY_OK, sizeof (db->data));
db->anydirty = 0;
}
return ok;
}
-/* Using the data cache DCACHE return the contents of the word at
- address ADDR in the remote machine.
-
- Returns 0 on error. */
-
-int
-dcache_peek (dcache, addr, data)
- DCACHE *dcache;
- CORE_ADDR addr;
- int *data;
-{
- unsigned char *dp = (unsigned char *) data;
- int i;
- for (i = 0; i < sizeof (int); i++)
- {
- if (!dcache_peek_byte (dcache, addr, dp + i))
- return 0;
- }
- return 1;
-}
-
-
/* Writeback any dirty lines to the remote. */
static int
dcache_writeback (dcache)
}
-/* Using the data cache DCACHE return the contents of the word at
- address ADDR in the remote machine. */
-int
-dcache_fetch (dcache, addr)
- DCACHE *dcache;
- CORE_ADDR addr;
-{
- int res;
- dcache_peek (dcache, addr, &res);
- return res;
-}
-
-
/* Write the byte at PTR into ADDR in the data cache.
Return zero on write error.
*/
-int
+static int
dcache_poke_byte (dcache, addr, ptr)
DCACHE *dcache;
CORE_ADDR addr;
return 1;
}
-/* Write the word at ADDR both in the data cache and in the remote machine.
- Return zero on write error.
- */
-
-int
-dcache_poke (dcache, addr, data)
- DCACHE *dcache;
- CORE_ADDR addr;
- int data;
-{
- unsigned char *dp = (unsigned char *) (&data);
- int i;
- for (i = 0; i < sizeof (int); i++)
- {
- if (!dcache_poke_byte (dcache, addr, dp + i))
- return 0;
- }
- dcache_writeback (dcache);
- return 1;
-}
-
-
/* Initialize the data cache. */
DCACHE *
dcache_init (reading, writing)
{
int i;
- if (remote_dcache)
+ if (dcache_enabled_p)
{
- int (*xfunc) ()
- = should_write ? dcache_poke_byte : dcache_peek_byte;
+ int (*xfunc) (DCACHE * dcache, CORE_ADDR addr, char *ptr);
+ xfunc = should_write ? dcache_poke_byte : dcache_peek_byte;
for (i = 0; i < len; i++)
{
dcache->cache_has_stuff = 1;
dcache_writeback (dcache);
}
- else
+ else
{
- int (*xfunc) ()
- = should_write ? dcache->write_memory : dcache->read_memory;
+ memxferfunc xfunc;
+ xfunc = should_write ? dcache->write_memory : dcache->read_memory;
if (dcache->cache_has_stuff)
dcache_flush (dcache);
return len;
}
-static void
+static void
dcache_info (exp, tty)
char *exp;
int tty;
{
struct dcache_block *p;
- if (!remote_dcache)
+ if (!dcache_enabled_p)
{
printf_filtered ("Dcache not enabled\n");
return;
for (p = last_cache->valid_head; p; p = p->p)
{
int j;
- printf_filtered ("Line at %08xd, referenced %d times\n",
- p->addr, p->refs);
+ printf_filtered ("Line at %s, referenced %d times\n",
+ paddr (p->addr), p->refs);
for (j = 0; j < LINE_SIZE; j++)
- printf_filtered ("%02x", p->data[j]);
+ printf_filtered ("%02x", p->data[j] & 0xFF);
printf_filtered ("\n");
for (j = 0; j < LINE_SIZE; j++)
- printf_filtered ("% 2x", p->state[j]);
+ printf_filtered (" %2x", p->state[j]);
printf_filtered ("\n");
}
}
+/* Turn dcache on or off. */
+void
+set_dcache_state (int what)
+{
+ dcache_enabled_p = !!what;
+}
+
void
_initialize_dcache ()
{
add_show_from_set
(add_set_cmd ("remotecache", class_support, var_boolean,
- (char *) &remote_dcache,
+ (char *) &dcache_enabled_p,
"\
Set cache use for remote targets.\n\
When on, use data caching for remote targets. For many remote targets\n\
this option can offer better throughput for reading target memory.\n\
Unfortunately, gdb does not currently know anything about volatile\n\
registers and thus data caching will produce incorrect results with\n\
-volatile registers are in use. By default, this option is on.",
+volatile registers are in use. By default, this option is off.",
&setlist),
&showlist);
projects / deliverable / binutils-gdb.git / blobdiff