summaryrefslogtreecommitdiffstats
path: root/arch/loongarch/include/asm/fpu.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/loongarch/include/asm/fpu.h')
-rw-r--r--arch/loongarch/include/asm/fpu.h318
1 files changed, 318 insertions, 0 deletions
diff --git a/arch/loongarch/include/asm/fpu.h b/arch/loongarch/include/asm/fpu.h
new file mode 100644
index 0000000000..c2d8962fda
--- /dev/null
+++ b/arch/loongarch/include/asm/fpu.h
@@ -0,0 +1,318 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Author: Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#ifndef _ASM_FPU_H
+#define _ASM_FPU_H
+
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/ptrace.h>
+#include <linux/thread_info.h>
+#include <linux/bitops.h>
+
+#include <asm/cpu.h>
+#include <asm/cpu-features.h>
+#include <asm/current.h>
+#include <asm/loongarch.h>
+#include <asm/processor.h>
+#include <asm/ptrace.h>
+
+struct sigcontext;
+
+extern void kernel_fpu_begin(void);
+extern void kernel_fpu_end(void);
+
+extern void _init_fpu(unsigned int);
+extern void _save_fp(struct loongarch_fpu *);
+extern void _restore_fp(struct loongarch_fpu *);
+
+extern void _save_lsx(struct loongarch_fpu *fpu);
+extern void _restore_lsx(struct loongarch_fpu *fpu);
+extern void _init_lsx_upper(void);
+extern void _restore_lsx_upper(struct loongarch_fpu *fpu);
+
+extern void _save_lasx(struct loongarch_fpu *fpu);
+extern void _restore_lasx(struct loongarch_fpu *fpu);
+extern void _init_lasx_upper(void);
+extern void _restore_lasx_upper(struct loongarch_fpu *fpu);
+
+static inline void enable_lsx(void);
+static inline void disable_lsx(void);
+static inline void save_lsx(struct task_struct *t);
+static inline void restore_lsx(struct task_struct *t);
+
+static inline void enable_lasx(void);
+static inline void disable_lasx(void);
+static inline void save_lasx(struct task_struct *t);
+static inline void restore_lasx(struct task_struct *t);
+
+/*
+ * Mask the FCSR Cause bits according to the Enable bits, observing
+ * that Unimplemented is always enabled.
+ */
+static inline unsigned long mask_fcsr_x(unsigned long fcsr)
+{
+ return fcsr & ((fcsr & FPU_CSR_ALL_E) <<
+ (ffs(FPU_CSR_ALL_X) - ffs(FPU_CSR_ALL_E)));
+}
+
+static inline int is_fp_enabled(void)
+{
+ return (csr_read32(LOONGARCH_CSR_EUEN) & CSR_EUEN_FPEN) ?
+ 1 : 0;
+}
+
+static inline int is_lsx_enabled(void)
+{
+ if (!cpu_has_lsx)
+ return 0;
+
+ return (csr_read32(LOONGARCH_CSR_EUEN) & CSR_EUEN_LSXEN) ?
+ 1 : 0;
+}
+
+static inline int is_lasx_enabled(void)
+{
+ if (!cpu_has_lasx)
+ return 0;
+
+ return (csr_read32(LOONGARCH_CSR_EUEN) & CSR_EUEN_LASXEN) ?
+ 1 : 0;
+}
+
+static inline int is_simd_enabled(void)
+{
+ return is_lsx_enabled() | is_lasx_enabled();
+}
+
+#define enable_fpu() set_csr_euen(CSR_EUEN_FPEN)
+
+#define disable_fpu() clear_csr_euen(CSR_EUEN_FPEN)
+
+#define clear_fpu_owner() clear_thread_flag(TIF_USEDFPU)
+
+static inline int is_fpu_owner(void)
+{
+ return test_thread_flag(TIF_USEDFPU);
+}
+
+static inline void __own_fpu(void)
+{
+ enable_fpu();
+ set_thread_flag(TIF_USEDFPU);
+ KSTK_EUEN(current) |= CSR_EUEN_FPEN;
+}
+
+static inline void own_fpu_inatomic(int restore)
+{
+ if (cpu_has_fpu && !is_fpu_owner()) {
+ __own_fpu();
+ if (restore)
+ _restore_fp(&current->thread.fpu);
+ }
+}
+
+static inline void own_fpu(int restore)
+{
+ preempt_disable();
+ own_fpu_inatomic(restore);
+ preempt_enable();
+}
+
+static inline void lose_fpu_inatomic(int save, struct task_struct *tsk)
+{
+ if (is_fpu_owner()) {
+ if (!is_simd_enabled()) {
+ if (save)
+ _save_fp(&tsk->thread.fpu);
+ disable_fpu();
+ } else {
+ if (save) {
+ if (!is_lasx_enabled())
+ save_lsx(tsk);
+ else
+ save_lasx(tsk);
+ }
+ disable_fpu();
+ disable_lsx();
+ disable_lasx();
+ clear_tsk_thread_flag(tsk, TIF_USEDSIMD);
+ }
+ clear_tsk_thread_flag(tsk, TIF_USEDFPU);
+ }
+ KSTK_EUEN(tsk) &= ~(CSR_EUEN_FPEN | CSR_EUEN_LSXEN | CSR_EUEN_LASXEN);
+}
+
+static inline void lose_fpu(int save)
+{
+ preempt_disable();
+ lose_fpu_inatomic(save, current);
+ preempt_enable();
+}
+
+static inline void init_fpu(void)
+{
+ unsigned int fcsr = current->thread.fpu.fcsr;
+
+ __own_fpu();
+ _init_fpu(fcsr);
+ set_used_math();
+}
+
+static inline void save_fp(struct task_struct *tsk)
+{
+ if (cpu_has_fpu)
+ _save_fp(&tsk->thread.fpu);
+}
+
+static inline void restore_fp(struct task_struct *tsk)
+{
+ if (cpu_has_fpu)
+ _restore_fp(&tsk->thread.fpu);
+}
+
+static inline void save_fpu_regs(struct task_struct *tsk)
+{
+ unsigned int euen;
+
+ if (tsk == current) {
+ preempt_disable();
+
+ euen = csr_read32(LOONGARCH_CSR_EUEN);
+
+#ifdef CONFIG_CPU_HAS_LASX
+ if (euen & CSR_EUEN_LASXEN)
+ _save_lasx(&current->thread.fpu);
+ else
+#endif
+#ifdef CONFIG_CPU_HAS_LSX
+ if (euen & CSR_EUEN_LSXEN)
+ _save_lsx(&current->thread.fpu);
+ else
+#endif
+ if (euen & CSR_EUEN_FPEN)
+ _save_fp(&current->thread.fpu);
+
+ preempt_enable();
+ }
+}
+
+static inline int is_simd_owner(void)
+{
+ return test_thread_flag(TIF_USEDSIMD);
+}
+
+#ifdef CONFIG_CPU_HAS_LSX
+
+static inline void enable_lsx(void)
+{
+ if (cpu_has_lsx)
+ csr_xchg32(CSR_EUEN_LSXEN, CSR_EUEN_LSXEN, LOONGARCH_CSR_EUEN);
+}
+
+static inline void disable_lsx(void)
+{
+ if (cpu_has_lsx)
+ csr_xchg32(0, CSR_EUEN_LSXEN, LOONGARCH_CSR_EUEN);
+}
+
+static inline void save_lsx(struct task_struct *t)
+{
+ if (cpu_has_lsx)
+ _save_lsx(&t->thread.fpu);
+}
+
+static inline void restore_lsx(struct task_struct *t)
+{
+ if (cpu_has_lsx)
+ _restore_lsx(&t->thread.fpu);
+}
+
+static inline void init_lsx_upper(void)
+{
+ if (cpu_has_lsx)
+ _init_lsx_upper();
+}
+
+static inline void restore_lsx_upper(struct task_struct *t)
+{
+ if (cpu_has_lsx)
+ _restore_lsx_upper(&t->thread.fpu);
+}
+
+#else
+static inline void enable_lsx(void) {}
+static inline void disable_lsx(void) {}
+static inline void save_lsx(struct task_struct *t) {}
+static inline void restore_lsx(struct task_struct *t) {}
+static inline void init_lsx_upper(void) {}
+static inline void restore_lsx_upper(struct task_struct *t) {}
+#endif
+
+#ifdef CONFIG_CPU_HAS_LASX
+
+static inline void enable_lasx(void)
+{
+
+ if (cpu_has_lasx)
+ csr_xchg32(CSR_EUEN_LASXEN, CSR_EUEN_LASXEN, LOONGARCH_CSR_EUEN);
+}
+
+static inline void disable_lasx(void)
+{
+ if (cpu_has_lasx)
+ csr_xchg32(0, CSR_EUEN_LASXEN, LOONGARCH_CSR_EUEN);
+}
+
+static inline void save_lasx(struct task_struct *t)
+{
+ if (cpu_has_lasx)
+ _save_lasx(&t->thread.fpu);
+}
+
+static inline void restore_lasx(struct task_struct *t)
+{
+ if (cpu_has_lasx)
+ _restore_lasx(&t->thread.fpu);
+}
+
+static inline void init_lasx_upper(void)
+{
+ if (cpu_has_lasx)
+ _init_lasx_upper();
+}
+
+static inline void restore_lasx_upper(struct task_struct *t)
+{
+ if (cpu_has_lasx)
+ _restore_lasx_upper(&t->thread.fpu);
+}
+
+#else
+static inline void enable_lasx(void) {}
+static inline void disable_lasx(void) {}
+static inline void save_lasx(struct task_struct *t) {}
+static inline void restore_lasx(struct task_struct *t) {}
+static inline void init_lasx_upper(void) {}
+static inline void restore_lasx_upper(struct task_struct *t) {}
+#endif
+
+static inline int thread_lsx_context_live(void)
+{
+ if (!cpu_has_lsx)
+ return 0;
+
+ return test_thread_flag(TIF_LSX_CTX_LIVE);
+}
+
+static inline int thread_lasx_context_live(void)
+{
+ if (!cpu_has_lasx)
+ return 0;
+
+ return test_thread_flag(TIF_LASX_CTX_LIVE);
+}
+
+#endif /* _ASM_FPU_H */