freebsd-nq/sys/sys/memrange.h
David Malone 93f39ea88a Some BIOSs are using MTRR values that are only documented under NDA
to control the mapping of things like the ACPI and APM into memory.

The problem is that starting X changes these values, so if something
was using the bits of BIOS mapped into memory (say ACPI or APM),
then next time they access this memory the machine would hang.

This patch refuse to change MTRR values it doesn't understand,
unless a new "force" option is given. This means X doesn't change
them by accident but someone can override that if they really want
to.

PR:		28418
Tested by:	Christopher Masto <chris@netmonger.net>,
		David Bushong <david@bushong.net>,
		Santos <casd@myrealbox.com>
MFC after:	1 week
2002-09-15 15:07:55 +00:00

72 lines
1.9 KiB
C

/*
* Memory range attribute operations, peformed on /dev/mem
*
* $FreeBSD$
*/
/* Memory range attributes */
#define MDF_UNCACHEABLE (1<<0) /* region not cached */
#define MDF_WRITECOMBINE (1<<1) /* region supports "write combine" action */
#define MDF_WRITETHROUGH (1<<2) /* write-through cached */
#define MDF_WRITEBACK (1<<3) /* write-back cached */
#define MDF_WRITEPROTECT (1<<4) /* read-only region */
#define MDF_UNKNOWN (1<<5) /* any state we don't understand */
#define MDF_ATTRMASK (0x00ffffff)
#define MDF_FIXBASE (1<<24) /* fixed base */
#define MDF_FIXLEN (1<<25) /* fixed length */
#define MDF_FIRMWARE (1<<26) /* set by firmware (XXX not useful?) */
#define MDF_ACTIVE (1<<27) /* currently active */
#define MDF_BOGUS (1<<28) /* we don't like it */
#define MDF_FIXACTIVE (1<<29) /* can't be turned off */
#define MDF_BUSY (1<<30) /* range is in use */
#define MDF_FORCE (1<<31) /* force risky changes */
struct mem_range_desc
{
u_int64_t mr_base;
u_int64_t mr_len;
int mr_flags;
char mr_owner[8];
};
struct mem_range_op
{
struct mem_range_desc *mo_desc;
int mo_arg[2];
#define MEMRANGE_SET_UPDATE 0
#define MEMRANGE_SET_REMOVE 1
/* XXX want a flag that says "set and undo when I exit" */
};
#define MEMRANGE_GET _IOWR('m', 50, struct mem_range_op)
#define MEMRANGE_SET _IOW('m', 51, struct mem_range_op)
#ifdef _KERNEL
MALLOC_DECLARE(M_MEMDESC);
struct mem_range_softc;
struct mem_range_ops
{
void (*init)(struct mem_range_softc *sc);
int (*set)(struct mem_range_softc *sc, struct mem_range_desc *mrd, int *arg);
void (*initAP)(struct mem_range_softc *sc);
};
struct mem_range_softc
{
struct mem_range_ops *mr_op;
int mr_cap;
int mr_ndesc;
struct mem_range_desc *mr_desc;
};
extern struct mem_range_softc mem_range_softc;
extern int mem_range_attr_get(struct mem_range_desc *mrd, int *arg);
extern int mem_range_attr_set(struct mem_range_desc *mrd, int *arg);
extern void mem_range_AP_init(void);
#endif