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barebox/arch/mips/lib/c-r4k.c

98 lines
2.6 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1996 David S. Miller (davem@davemloft.net)
* Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Ralf Baechle (ralf@gnu.org)
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
*/
#include <common.h>
#include <asm/io.h>
#include <asm/mipsregs.h>
#include <asm/cpu.h>
#include <asm/cpu-info.h>
#include <asm/bitops.h>
void r4k_cache_init(void);
static void probe_pcache(void)
{
struct cpuinfo_mips *c = &current_cpu_data;
unsigned int icache_size, dcache_size;
unsigned int config = read_c0_config();
unsigned long config1;
unsigned int lsize;
switch (c->cputype) {
default:
/*
* So we seem to be a MIPS32 or MIPS64 CPU
* So let's probe the I-cache ...
*/
config1 = read_c0_config1();
if ((lsize = ((config1 >> 19) & 7)))
c->icache.linesz = 2 << lsize;
else
c->icache.linesz = lsize;
c->icache.sets = 64 << ((config1 >> 22) & 7);
c->icache.ways = 1 + ((config1 >> 16) & 7);
icache_size = c->icache.sets *
c->icache.ways *
c->icache.linesz;
c->icache.waybit = __ffs(icache_size/c->icache.ways);
if (config & 0x8) /* VI bit */
c->icache.flags |= MIPS_CACHE_VTAG;
/*
* Now probe the MIPS32 / MIPS64 data cache.
*/
c->dcache.flags = 0;
if ((lsize = ((config1 >> 10) & 7)))
c->dcache.linesz = 2 << lsize;
else
c->dcache.linesz= lsize;
c->dcache.sets = 64 << ((config1 >> 13) & 7);
c->dcache.ways = 1 + ((config1 >> 7) & 7);
dcache_size = c->dcache.sets *
c->dcache.ways *
c->dcache.linesz;
c->dcache.waybit = __ffs(dcache_size/c->dcache.ways);
c->options |= MIPS_CPU_PREFETCH;
break;
}
/* compute a couple of other cache variables */
c->icache.waysize = icache_size / c->icache.ways;
c->dcache.waysize = dcache_size / c->dcache.ways;
c->icache.sets = c->icache.linesz ?
icache_size / (c->icache.linesz * c->icache.ways) : 0;
c->dcache.sets = c->dcache.linesz ?
dcache_size / (c->dcache.linesz * c->dcache.ways) : 0;
/*
* R10000 and R12000 P-caches are odd in a positive way. They're 32kB
* 2-way virtually indexed so normally would suffer from aliases. So
* normally they'd suffer from aliases but magic in the hardware deals
* with that for us so we don't need to take care ourselves.
*/
switch (c->cputype) {
default:
if (c->dcache.waysize > PAGE_SIZE)
c->dcache.flags |= MIPS_CACHE_ALIASES;
}
}
void r4k_cache_init(void)
{
probe_pcache();
}