mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

sparc: Handle negative offsets in arch_jump_label_transform 

Additionally, if the offset will overflow the immediate for a ba,pt
instruction, fall back on a standard ba to get an extra 3 bits.

Signed-off-by: James Clarke <jrtc27@jrtc27.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
James Clarke 2016-10-24 19:49:25 +01:00 committed by David S. Miller
parent b429ae4d5b
commit 9d9fa23020
1 changed files with 17 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
arch/sparc/kernel/jump_label.c
View File

@ -13,19 +13,30 @@
void arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
u32 val;
u32 *insn = (u32 *) (unsigned long) entry->code;
u32 val;
if (type == JUMP_LABEL_JMP) {
s32 off = (s32)entry->target - (s32)entry->code;
bool use_v9_branch = false;
BUG_ON(off & 3);
#ifdef CONFIG_SPARC64
/* ba,pt %xcc, . + (off << 2) */
val = 0x10680000 | ((u32) off >> 2);
#else
/* ba . + (off << 2) */
val = 0x10800000 | ((u32) off >> 2);
if (off <= 0xfffff && off >= -0x100000)
use_v9_branch = true;
#endif
if (use_v9_branch) {
/* WDISP19 - target is . + immed << 2 */
/* ba,pt %xcc, . + off */
val = 0x10680000 | (((u32) off >> 2) & 0x7ffff);
} else {
/* WDISP22 - target is . + immed << 2 */
BUG_ON(off > 0x7fffff);
BUG_ON(off < -0x800000);
/* ba . + off */
val = 0x10800000 | (((u32) off >> 2) & 0x3fffff);
}
} else {
val = 0x01000000;
}