s390/kernel: introduce fpu-internal.h with fpu helper functions

Introduce a new structure to manage FP and VX registers. Refactor the
save and restore of floating point and vector registers with a set
of helper functions in fpu-internal.h.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/arch/s390/include/asm/fpu-internal.h b/arch/s390/include/asm/fpu-internal.h
new file mode 100644 (file)
index 0000000..04b4cfc
--- /dev/null
+++ b/arch/s390/include/asm/fpu-internal.h
@@ -0,0 +1,191 @@
+/*
+ * General floating pointer and vector register helpers
+ *
+ * Copyright IBM Corp. 2015
+ * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
+ */
+
+#ifndef _ASM_S390_FPU_INTERNAL_H
+#define _ASM_S390_FPU_INTERNAL_H
+
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <asm/linkage.h>
+#include <asm/ctl_reg.h>
+#include <asm/sigcontext.h>
+
+struct fpu {
+       __u32 fpc;                      /* Floating-point control */
+       __u32 pad;
+       freg_t fprs[__NUM_FPRS];        /* Floating-point register save area */
+       __vector128 *vxrs;              /* Vector register save area */
+};
+
+#define is_vx_fpu(fpu) (!!(fpu)->vxrs)
+#define is_vx_task(tsk) (!!(tsk)->thread.fpu.vxrs)
+
+static inline int test_fp_ctl(u32 fpc)
+{
+       u32 orig_fpc;
+       int rc;
+
+       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)
+{
+       asm volatile(
+               "       stfpc   %0\n"
+               : "+Q" (*fpc));
+}
+
+static inline int restore_fp_ctl(u32 *fpc)
+{
+       int rc;
+
+       asm volatile(
+               "       lfpc    %1\n"
+               "0:     la      %0,0\n"
+               "1:\n"
+               : "=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]));
+       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]));
+       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 convert_vx_to_fp(freg_t *fprs, __vector128 *vxrs)
+{
+       int i;
+
+       for (i = 0; i < __NUM_FPRS; i++)
+               fprs[i] = *(freg_t *)(vxrs + i);
+}
+
+static inline void convert_fp_to_vx(__vector128 *vxrs, freg_t *fprs)
+{
+       int i;
+
+       for (i = 0; i < __NUM_FPRS; i++)
+               *(freg_t *)(vxrs + i) = fprs[i];
+}
+
+static inline void fpregs_store(_s390_fp_regs *fpregs, struct fpu *fpu)
+{
+       fpregs->pad = 0;
+       if (is_vx_fpu(fpu))
+               convert_vx_to_fp((freg_t *)&fpregs->fprs, fpu->vxrs);
+       else
+               memcpy((freg_t *)&fpregs->fprs, fpu->fprs,
+                      sizeof(fpregs->fprs));
+}
+
+static inline void fpregs_load(_s390_fp_regs *fpregs, struct fpu *fpu)
+{
+       if (is_vx_fpu(fpu))
+               convert_fp_to_vx(fpu->vxrs, (freg_t *)&fpregs->fprs);
+       else
+               memcpy(fpu->fprs, (freg_t *)&fpregs->fprs,
+                      sizeof(fpregs->fprs));
+}
+
+static inline void save_fpu_regs(struct fpu *fpu)
+{
+       save_fp_ctl(&fpu->fpc);
+       if (is_vx_fpu(fpu))
+               save_vx_regs(fpu->vxrs);
+       else
+               save_fp_regs(fpu->fprs);
+}
+
+static inline void restore_fpu_regs(struct fpu *fpu)
+{
+       restore_fp_ctl(&fpu->fpc);
+       if (is_vx_fpu(fpu))
+               restore_vx_regs(fpu->vxrs);
+       else
+               restore_fp_regs(fpu->fprs);
+}
+
+#endif /* _ASM_S390_FPU_INTERNAL_H */

diff --cc arch/s390/include/asm/processor.h
Simple merge

diff --cc arch/s390/include/asm/switch_to.h
Simple merge

diff --cc arch/s390/kernel/compat_signal.c
Simple merge

diff --cc arch/s390/kernel/nmi.c
Simple merge

diff --cc arch/s390/kernel/process.c
Simple merge

diff --cc arch/s390/kernel/ptrace.c
Simple merge

diff --cc arch/s390/kernel/signal.c
Simple merge

diff --cc arch/s390/kernel/traps.c
Simple merge