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Diffstat (limited to 'arch/sparc/include/asm/vac-ops.h')
| -rw-r--r-- | arch/sparc/include/asm/vac-ops.h | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/arch/sparc/include/asm/vac-ops.h b/arch/sparc/include/asm/vac-ops.h new file mode 100644 index 00000000000..d10527611f1 --- /dev/null +++ b/arch/sparc/include/asm/vac-ops.h @@ -0,0 +1,134 @@ +#ifndef _SPARC_VAC_OPS_H +#define _SPARC_VAC_OPS_H + +/* vac-ops.h: Inline assembly routines to do operations on the Sparc + * VAC (virtual address cache) for the sun4c. + * + * Copyright (C) 1994, David S. Miller (davem@caip.rutgers.edu) + */ + +#include <asm/sysen.h> +#include <asm/contregs.h> +#include <asm/asi.h> + +/* The SUN4C models have a virtually addressed write-through + * cache. + * + * The cache tags are directly accessible through an ASI and + * each have the form: + * + * ------------------------------------------------------------ + * | MBZ | CONTEXT | WRITE | PRIV | VALID | MBZ | TagID | MBZ | + * ------------------------------------------------------------ + * 31 25 24 22 21 20 19 18 16 15 2 1 0 + * + * MBZ: These bits are either unused and/or reserved and should + * be written as zeroes. + * + * CONTEXT: Records the context to which this cache line belongs. + * + * WRITE: A copy of the writable bit from the mmu pte access bits. + * + * PRIV: A copy of the privileged bit from the pte access bits. + * + * VALID: If set, this line is valid, else invalid. + * + * TagID: Fourteen bits of tag ID. + * + * Every virtual address is seen by the cache like this: + * + * ---------------------------------------- + * | RESV | TagID | LINE | BYTE-in-LINE | + * ---------------------------------------- + * 31 30 29 16 15 4 3 0 + * + * RESV: Unused/reserved. + * + * TagID: Used to match the Tag-ID in that vac tags. + * + * LINE: Which line within the cache + * + * BYTE-in-LINE: Which byte within the cache line. + */ + +/* Sun4c VAC Tags */ +#define S4CVACTAG_CID 0x01c00000 +#define S4CVACTAG_W 0x00200000 +#define S4CVACTAG_P 0x00100000 +#define S4CVACTAG_V 0x00080000 +#define S4CVACTAG_TID 0x0000fffc + +/* Sun4c VAC Virtual Address */ +/* These aren't used, why bother? (Anton) */ +#if 0 +#define S4CVACVA_TID 0x3fff0000 +#define S4CVACVA_LINE 0x0000fff0 +#define S4CVACVA_BIL 0x0000000f +#endif + +/* The indexing of cache lines creates a problem. Because the line + * field of a virtual address extends past the page offset within + * the virtual address it is possible to have what are called + * 'bad aliases' which will create inconsistencies. So we must make + * sure that within a context that if a physical page is mapped + * more than once, that 'extra' line bits are the same. If this is + * not the case, and thus is a 'bad alias' we must turn off the + * cacheable bit in the pte's of all such pages. + */ + +#ifdef CONFIG_SUN4 +#define S4CVAC_BADBITS 0x0001e000 +#else +#define S4CVAC_BADBITS 0x0000f000 +#endif + +/* The following is true if vaddr1 and vaddr2 would cause + * a 'bad alias'. + */ +#define S4CVAC_BADALIAS(vaddr1, vaddr2) \ + ((((unsigned long) (vaddr1)) ^ ((unsigned long) (vaddr2))) & \ + (S4CVAC_BADBITS)) + +/* The following structure describes the characteristics of a sun4c + * VAC as probed from the prom during boot time. + */ +struct sun4c_vac_props { + unsigned int num_bytes; /* Size of the cache */ + unsigned int num_lines; /* Number of cache lines */ + unsigned int do_hwflushes; /* Hardware flushing available? */ + enum { VAC_NONE, VAC_WRITE_THROUGH, + VAC_WRITE_BACK } type; /* What type of VAC? */ + unsigned int linesize; /* Size of each line in bytes */ + unsigned int log2lsize; /* log2(linesize) */ + unsigned int on; /* VAC is enabled */ +}; + +extern struct sun4c_vac_props sun4c_vacinfo; + +/* sun4c_enable_vac() enables the sun4c virtual address cache. */ +static inline void sun4c_enable_vac(void) +{ + __asm__ __volatile__("lduba [%0] %1, %%g1\n\t" + "or %%g1, %2, %%g1\n\t" + "stba %%g1, [%0] %1\n\t" + : /* no outputs */ + : "r" ((unsigned int) AC_SENABLE), + "i" (ASI_CONTROL), "i" (SENABLE_CACHE) + : "g1", "memory"); + sun4c_vacinfo.on = 1; +} + +/* sun4c_disable_vac() disables the virtual address cache. */ +static inline void sun4c_disable_vac(void) +{ + __asm__ __volatile__("lduba [%0] %1, %%g1\n\t" + "andn %%g1, %2, %%g1\n\t" + "stba %%g1, [%0] %1\n\t" + : /* no outputs */ + : "r" ((unsigned int) AC_SENABLE), + "i" (ASI_CONTROL), "i" (SENABLE_CACHE) + : "g1", "memory"); + sun4c_vacinfo.on = 0; +} + +#endif /* !(_SPARC_VAC_OPS_H) */ |