tjh.dev
+8
arch/arc/Kconfig
+8
arch/arc/Kconfig
···
406
406
bool "Insn: div, divu, rem, remu"
407
407
default y
408
408
409
+
config ARC_HAS_ACCL_REGS
410
+
bool "Reg Pair ACCL:ACCH (FPU and/or MPY > 6)"
411
+
default n
412
+
help
413
+
Depending on the configuration, CPU can contain accumulator reg-pair
414
+
(also referred to as r58:r59). These can also be used by gcc as GPR so
415
+
kernel needs to save/restore per process
416
+
409
417
endif # ISA_ARCV2
410
418
411
419
endmenu # "ARC CPU Configuration"
+2
-1
arch/arc/include/asm/atomic.h
+2
-1
arch/arc/include/asm/atomic.h
+10
arch/arc/include/asm/entry-arcv2.h
+10
arch/arc/include/asm/entry-arcv2.h
···
16
16
;
17
17
; Now manually save: r12, sp, fp, gp, r25
18
18
19
+
#ifdef CONFIG_ARC_HAS_ACCL_REGS
20
+
PUSH r59
21
+
PUSH r58
22
+
#endif
23
+
19
24
PUSH r30
20
25
PUSH r12
21
26
···
79
74
1:
80
75
POP r12
81
76
POP r30
77
+
78
+
#ifdef CONFIG_ARC_HAS_ACCL_REGS
79
+
POP r58
80
+
POP r59
81
+
#endif
82
82
83
83
.endm
84
84
+4
arch/arc/include/asm/ptrace.h
+4
arch/arc/include/asm/ptrace.h
···
86
86
87
87
unsigned long r12, r30;
88
88
89
+
#ifdef CONFIG_ARC_HAS_ACCL_REGS
90
+
unsigned long r58, r59; /* ACCL/ACCH used by FPU / DSP MPY */
91
+
#endif
92
+
89
93
/*------- Below list auto saved by h/w -----------*/
90
94
unsigned long r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11;
91
95
+21
-9
arch/arc/kernel/setup.c
+21
-9
arch/arc/kernel/setup.c
···
319
319
static void arc_chk_core_config(void)
320
320
{
321
321
struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
322
-
int fpu_enabled;
322
+
int saved = 0, present = 0;
323
+
char *opt_nm = NULL;;
323
324
324
325
if (!cpu->extn.timer0)
325
326
panic("Timer0 is not present!\n");
···
347
346
348
347
/*
349
348
* FP hardware/software config sanity
350
-
* -If hardware contains DPFP, kernel needs to save/restore FPU state
349
+
* -If hardware present, kernel needs to save/restore FPU state
351
350
* -If not, it will crash trying to save/restore the non-existant regs
352
-
*
353
-
* (only DPDP checked since SP has no arch visible regs)
354
351
*/
355
-
fpu_enabled = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
356
352
357
-
if (cpu->extn.fpu_dp && !fpu_enabled)
358
-
pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
359
-
else if (!cpu->extn.fpu_dp && fpu_enabled)
360
-
panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
353
+
if (is_isa_arcompact()) {
354
+
opt_nm = "CONFIG_ARC_FPU_SAVE_RESTORE";
355
+
saved = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
356
+
357
+
/* only DPDP checked since SP has no arch visible regs */
358
+
present = cpu->extn.fpu_dp;
359
+
} else {
360
+
opt_nm = "CONFIG_ARC_HAS_ACCL_REGS";
361
+
saved = IS_ENABLED(CONFIG_ARC_HAS_ACCL_REGS);
362
+
363
+
/* Accumulator Low:High pair (r58:59) present if DSP MPY or FPU */
364
+
present = cpu->extn_mpy.dsp | cpu->extn.fpu_sp | cpu->extn.fpu_dp;
365
+
}
366
+
367
+
if (present && !saved)
368
+
pr_warn("Enable %s for working apps\n", opt_nm);
369
+
else if (!present && saved)
370
+
panic("Disable %s, hardware NOT present\n", opt_nm);
361
371
}
362
372
363
373
/*