mirror/freebsd
1
0
Fork 0
mirror of https://git.FreeBSD.org/src.git synced 2024-11-25 07:49:18 +00:00
Code Issues Releases Activity

Add an loader command on arm64 to sync the cache

Browse Source 
On boot we don't need to perform any CPU cache management when the IDC
and DIC fields in the ctr_el0 register are set. Add a command to tell
loader to ignore these fields. This could be useful, for example, if the
hardware is misreporting the values and we are missing a quirk to enable
it.

It is not expected this will be needed, but is only intended as a
workaround to ensure the kernel can still boot.

Sponsored by:	The FreeBSD Foundation
This commit is contained in:
Andrew Turner 2021-12-20 13:42:15 +00:00
parent c1381f07f6
commit c399283c71
1 changed files with 38 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
stand/arm64/libarm64/cache.c
View File

@ -37,17 +37,30 @@ __FBSDID("$FreeBSD$");
#include <stand.h>
#include <efi.h>
#include "bootstrap.h"
#include "cache.h"
static long cache_flags;
#define CACHE_FLAG_DIC_OFF (1<<0)
#define CACHE_FLAG_IDC_OFF (1<<1)
static bool
get_cache_dic(uint64_t ctr)
{
if ((cache_flags & CACHE_FLAG_DIC_OFF) != 0) {
return (false);
}
return (CTR_DIC_VAL(ctr) != 0);
}
static bool
get_cache_idc(uint64_t ctr)
{
if ((cache_flags & CACHE_FLAG_IDC_OFF) != 0) {
return (false);
}
return (CTR_IDC_VAL(ctr) != 0);
}
@ -112,3 +125,28 @@ cpu_inval_icache(void)
: : : "memory");
}
}
static int
command_cache_flags(int argc, char *argv[])
{
char *cp;
long new_flags;
if (argc == 3) {
if (strcmp(argv[1], "set") == 0) {
new_flags = strtol(argv[2], &cp, 0);
if (cp[0] != '\0') {
printf("Invalid flags\n");
} else {
printf("Setting cache flags to %#lx\n",
new_flags);
cache_flags = new_flags;
return (CMD_OK);
}
}
}
printf("usage: cache_flags set <value>\n");
return (CMD_ERROR);
}
COMMAND_SET(cache_flags, "cache_flags", "Set cache flags", command_cache_flags);