linux/arch/s390/include/asm/switch_to.h
Michael Holzheu a62bc07392 s390/kdump: add support for vector extension
With this patch for kdump the s390 vector registers are stored into the
prepared save areas in the old kernel and into the REGSET_VX_LOW and
REGSET_VX_HIGH ELF notes for /proc/vmcore in the new kernel.

The NT_S390_VXRS_LOW note contains the lower halves of the first 16 vector
registers 0-15. The higher halves are stored in the floating point register
ELF note.  The NT_S390_VXRS_HIGH contains the full vector registers 16-31.

The kernel provides a save area for storing vector register in case of
machine checks. A pointer to this save are is stored in the CPU lowcore
at offset 0x11b0. This save area is also used to save the registers for
kdump. In case of a dumped crashed kdump those areas are used to extract
the registers of the production system.

The vector registers for remote CPUs are stored using the "store additional
status at address" SIGP. For the dump CPU the vector registers are stored
with the VSTM instruction.

With this patch also zfcpdump stores the vector registers.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-10-09 09:14:16 +02:00

193 lines
4.7 KiB
C

/*
* Copyright IBM Corp. 1999, 2009
*
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
*/
#ifndef __ASM_SWITCH_TO_H
#define __ASM_SWITCH_TO_H
#include <linux/thread_info.h>
#include <asm/ptrace.h>
extern struct task_struct *__switch_to(void *, void *);
extern void update_cr_regs(struct task_struct *task);
static inline int test_fp_ctl(u32 fpc)
{
u32 orig_fpc;
int rc;
if (!MACHINE_HAS_IEEE)
return 0;
asm volatile(
" efpc %1\n"
" sfpc %2\n"
"0: sfpc %1\n"
" la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc), "=d" (orig_fpc)
: "d" (fpc), "0" (-EINVAL));
return rc;
}
static inline void save_fp_ctl(u32 *fpc)
{
if (!MACHINE_HAS_IEEE)
return;
asm volatile(
" stfpc %0\n"
: "+Q" (*fpc));
}
static inline int restore_fp_ctl(u32 *fpc)
{
int rc;
if (!MACHINE_HAS_IEEE)
return 0;
asm volatile(
" lfpc %1\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc) : "Q" (*fpc), "0" (-EINVAL));
return rc;
}
static inline void save_fp_regs(freg_t *fprs)
{
asm volatile("std 0,%0" : "=Q" (fprs[0]));
asm volatile("std 2,%0" : "=Q" (fprs[2]));
asm volatile("std 4,%0" : "=Q" (fprs[4]));
asm volatile("std 6,%0" : "=Q" (fprs[6]));
if (!MACHINE_HAS_IEEE)
return;
asm volatile("std 1,%0" : "=Q" (fprs[1]));
asm volatile("std 3,%0" : "=Q" (fprs[3]));
asm volatile("std 5,%0" : "=Q" (fprs[5]));
asm volatile("std 7,%0" : "=Q" (fprs[7]));
asm volatile("std 8,%0" : "=Q" (fprs[8]));
asm volatile("std 9,%0" : "=Q" (fprs[9]));
asm volatile("std 10,%0" : "=Q" (fprs[10]));
asm volatile("std 11,%0" : "=Q" (fprs[11]));
asm volatile("std 12,%0" : "=Q" (fprs[12]));
asm volatile("std 13,%0" : "=Q" (fprs[13]));
asm volatile("std 14,%0" : "=Q" (fprs[14]));
asm volatile("std 15,%0" : "=Q" (fprs[15]));
}
static inline void restore_fp_regs(freg_t *fprs)
{
asm volatile("ld 0,%0" : : "Q" (fprs[0]));
asm volatile("ld 2,%0" : : "Q" (fprs[2]));
asm volatile("ld 4,%0" : : "Q" (fprs[4]));
asm volatile("ld 6,%0" : : "Q" (fprs[6]));
if (!MACHINE_HAS_IEEE)
return;
asm volatile("ld 1,%0" : : "Q" (fprs[1]));
asm volatile("ld 3,%0" : : "Q" (fprs[3]));
asm volatile("ld 5,%0" : : "Q" (fprs[5]));
asm volatile("ld 7,%0" : : "Q" (fprs[7]));
asm volatile("ld 8,%0" : : "Q" (fprs[8]));
asm volatile("ld 9,%0" : : "Q" (fprs[9]));
asm volatile("ld 10,%0" : : "Q" (fprs[10]));
asm volatile("ld 11,%0" : : "Q" (fprs[11]));
asm volatile("ld 12,%0" : : "Q" (fprs[12]));
asm volatile("ld 13,%0" : : "Q" (fprs[13]));
asm volatile("ld 14,%0" : : "Q" (fprs[14]));
asm volatile("ld 15,%0" : : "Q" (fprs[15]));
}
static inline void save_vx_regs(__vector128 *vxrs)
{
typedef struct { __vector128 _[__NUM_VXRS]; } addrtype;
asm volatile(
" la 1,%0\n"
" .word 0xe70f,0x1000,0x003e\n" /* vstm 0,15,0(1) */
" .word 0xe70f,0x1100,0x0c3e\n" /* vstm 16,31,256(1) */
: "=Q" (*(addrtype *) vxrs) : : "1");
}
static inline void save_vx_regs_safe(__vector128 *vxrs)
{
unsigned long cr0, flags;
flags = arch_local_irq_save();
__ctl_store(cr0, 0, 0);
__ctl_set_bit(0, 17);
__ctl_set_bit(0, 18);
save_vx_regs(vxrs);
__ctl_load(cr0, 0, 0);
arch_local_irq_restore(flags);
}
static inline void restore_vx_regs(__vector128 *vxrs)
{
typedef struct { __vector128 _[__NUM_VXRS]; } addrtype;
asm volatile(
" la 1,%0\n"
" .word 0xe70f,0x1000,0x0036\n" /* vlm 0,15,0(1) */
" .word 0xe70f,0x1100,0x0c36\n" /* vlm 16,31,256(1) */
: : "Q" (*(addrtype *) vxrs) : "1");
}
static inline void save_fp_vx_regs(struct task_struct *task)
{
#ifdef CONFIG_64BIT
if (task->thread.vxrs)
save_vx_regs(task->thread.vxrs);
else
#endif
save_fp_regs(task->thread.fp_regs.fprs);
}
static inline void restore_fp_vx_regs(struct task_struct *task)
{
#ifdef CONFIG_64BIT
if (task->thread.vxrs)
restore_vx_regs(task->thread.vxrs);
else
#endif
restore_fp_regs(task->thread.fp_regs.fprs);
}
static inline void save_access_regs(unsigned int *acrs)
{
typedef struct { int _[NUM_ACRS]; } acrstype;
asm volatile("stam 0,15,%0" : "=Q" (*(acrstype *)acrs));
}
static inline void restore_access_regs(unsigned int *acrs)
{
typedef struct { int _[NUM_ACRS]; } acrstype;
asm volatile("lam 0,15,%0" : : "Q" (*(acrstype *)acrs));
}
#define switch_to(prev,next,last) do { \
if (prev->mm) { \
save_fp_ctl(&prev->thread.fp_regs.fpc); \
save_fp_vx_regs(prev); \
save_access_regs(&prev->thread.acrs[0]); \
save_ri_cb(prev->thread.ri_cb); \
} \
if (next->mm) { \
update_cr_regs(next); \
restore_fp_ctl(&next->thread.fp_regs.fpc); \
restore_fp_vx_regs(next); \
restore_access_regs(&next->thread.acrs[0]); \
restore_ri_cb(next->thread.ri_cb, prev->thread.ri_cb); \
} \
prev = __switch_to(prev,next); \
} while (0)
#endif /* __ASM_SWITCH_TO_H */