123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154 |
- /* SPDX-License-Identifier: GPL-2.0-or-later */
- /*
- * FPU support code, moved here from head.S so that it can be used
- * by chips which use other head-whatever.S files.
- *
- * Copyright (C) 1995-1996 Gary Thomas ([email protected])
- * Copyright (C) 1996 Cort Dougan <[email protected]>
- * Copyright (C) 1996 Paul Mackerras.
- * Copyright (C) 1997 Dan Malek ([email protected]).
- */
- #include <asm/reg.h>
- #include <asm/page.h>
- #include <asm/mmu.h>
- #include <asm/cputable.h>
- #include <asm/cache.h>
- #include <asm/thread_info.h>
- #include <asm/ppc_asm.h>
- #include <asm/asm-offsets.h>
- #include <asm/ptrace.h>
- #include <asm/export.h>
- #include <asm/asm-compat.h>
- #include <asm/feature-fixups.h>
- #ifdef CONFIG_VSX
- #define __REST_1FPVSR(n,c,base) \
- BEGIN_FTR_SECTION \
- b 2f; \
- END_FTR_SECTION_IFSET(CPU_FTR_VSX); \
- REST_FPR(n,base); \
- b 3f; \
- 2: REST_VSR(n,c,base); \
- 3:
- #define __REST_32FPVSRS(n,c,base) \
- BEGIN_FTR_SECTION \
- b 2f; \
- END_FTR_SECTION_IFSET(CPU_FTR_VSX); \
- REST_32FPRS(n,base); \
- b 3f; \
- 2: REST_32VSRS(n,c,base); \
- 3:
- #define __SAVE_32FPVSRS(n,c,base) \
- BEGIN_FTR_SECTION \
- b 2f; \
- END_FTR_SECTION_IFSET(CPU_FTR_VSX); \
- SAVE_32FPRS(n,base); \
- b 3f; \
- 2: SAVE_32VSRS(n,c,base); \
- 3:
- #else
- #define __REST_1FPVSR(n,b,base) REST_FPR(n, base)
- #define __REST_32FPVSRS(n,b,base) REST_32FPRS(n, base)
- #define __SAVE_32FPVSRS(n,b,base) SAVE_32FPRS(n, base)
- #endif
- #define REST_1FPVSR(n,c,base) __REST_1FPVSR(n,__REG_##c,__REG_##base)
- #define REST_32FPVSRS(n,c,base) __REST_32FPVSRS(n,__REG_##c,__REG_##base)
- #define SAVE_32FPVSRS(n,c,base) __SAVE_32FPVSRS(n,__REG_##c,__REG_##base)
- /*
- * Load state from memory into FP registers including FPSCR.
- * Assumes the caller has enabled FP in the MSR.
- */
- _GLOBAL(load_fp_state)
- lfd fr0,FPSTATE_FPSCR(r3)
- MTFSF_L(fr0)
- REST_32FPVSRS(0, R4, R3)
- blr
- EXPORT_SYMBOL(load_fp_state)
- _ASM_NOKPROBE_SYMBOL(load_fp_state); /* used by restore_math */
- /*
- * Store FP state into memory, including FPSCR
- * Assumes the caller has enabled FP in the MSR.
- */
- _GLOBAL(store_fp_state)
- SAVE_32FPVSRS(0, R4, R3)
- mffs fr0
- stfd fr0,FPSTATE_FPSCR(r3)
- REST_1FPVSR(0, R4, R3)
- blr
- EXPORT_SYMBOL(store_fp_state)
- /*
- * This task wants to use the FPU now.
- * On UP, disable FP for the task which had the FPU previously,
- * and save its floating-point registers in its thread_struct.
- * Load up this task's FP registers from its thread_struct,
- * enable the FPU for the current task and return to the task.
- * Note that on 32-bit this can only use registers that will be
- * restored by fast_exception_return, i.e. r3 - r6, r10 and r11.
- */
- _GLOBAL(load_up_fpu)
- mfmsr r5
- #ifdef CONFIG_PPC_BOOK3S_64
- /* interrupt doesn't set MSR[RI] and HPT can fault on current access */
- ori r5,r5,MSR_FP|MSR_RI
- #else
- ori r5,r5,MSR_FP
- #endif
- #ifdef CONFIG_VSX
- BEGIN_FTR_SECTION
- oris r5,r5,MSR_VSX@h
- END_FTR_SECTION_IFSET(CPU_FTR_VSX)
- #endif
- MTMSRD(r5) /* enable use of fpu now */
- isync
- /* enable use of FP after return */
- #ifdef CONFIG_PPC32
- addi r5,r2,THREAD
- lwz r4,THREAD_FPEXC_MODE(r5)
- ori r9,r9,MSR_FP /* enable FP for current */
- or r9,r9,r4
- #else
- ld r4,PACACURRENT(r13)
- addi r5,r4,THREAD /* Get THREAD */
- lwz r4,THREAD_FPEXC_MODE(r5)
- ori r12,r12,MSR_FP
- or r12,r12,r4
- std r12,_MSR(r1)
- #ifdef CONFIG_PPC_BOOK3S_64
- li r4,0
- stb r4,PACASRR_VALID(r13)
- #endif
- #endif
- li r4,1
- stb r4,THREAD_LOAD_FP(r5)
- addi r10,r5,THREAD_FPSTATE
- lfd fr0,FPSTATE_FPSCR(r10)
- MTFSF_L(fr0)
- REST_32FPVSRS(0, R4, R10)
- /* restore registers and return */
- /* we haven't used ctr or xer or lr */
- blr
- _ASM_NOKPROBE_SYMBOL(load_up_fpu)
- /*
- * save_fpu(tsk)
- * Save the floating-point registers in its thread_struct.
- * Enables the FPU for use in the kernel on return.
- */
- _GLOBAL(save_fpu)
- addi r3,r3,THREAD /* want THREAD of task */
- PPC_LL r6,THREAD_FPSAVEAREA(r3)
- PPC_LL r5,PT_REGS(r3)
- PPC_LCMPI 0,r6,0
- bne 2f
- addi r6,r3,THREAD_FPSTATE
- 2: SAVE_32FPVSRS(0, R4, R6)
- mffs fr0
- stfd fr0,FPSTATE_FPSCR(r6)
- REST_1FPVSR(0, R4, R6)
- blr
|