LoongArch: Remove obsolete mentions of vcsr

The `vcsr` only exists in the old hardware design, it isn't used in any
shipped hardware from Loongson-3A5000 on. Both scalar FP and LSX/LASX
instructions use the `fcsr` as their control and status registers now.
For example, the RM control bit in fcsr0 is shared by FP, LSX and LASX
instructions.

Particularly, fcsr16 to fcsr31 are reserved for LSX/LASX now, access to
these registers has no visible effect if LSX/LASX is enabled, and will
cause SXD/ASXD exceptions if LSX/LASX is not enabled.

So, mentions of vcsr are obsolete in the first place (it was just used
for debugging), let's remove them.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Qi Hu <huqi@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

diff --git a/arch/loongarch/include/asm/fpregdef.h b/arch/loongarch/include/asm/fpregdef.h
index adb16e4..b6be527 100644 (file)
--- a/arch/loongarch/include/asm/fpregdef.h
+++ b/arch/loongarch/include/asm/fpregdef.h
@@ -48,6 +48,5 @@
 #define fcsr1  $r1
 #define fcsr2  $r2
 #define fcsr3  $r3
-#define vcsr16 $r16
 
 #endif /* _ASM_FPREGDEF_H */

diff --git a/arch/loongarch/include/asm/processor.h b/arch/loongarch/include/asm/processor.h
index 1d63c93..57ec45a 100644 (file)
--- a/arch/loongarch/include/asm/processor.h
+++ b/arch/loongarch/include/asm/processor.h
@@ -80,7 +80,6 @@ BUILD_FPR_ACCESS(64)
 
 struct loongarch_fpu {
        unsigned int    fcsr;
-       unsigned int    vcsr;
        uint64_t        fcc;    /* 8x8 */
        union fpureg    fpr[NUM_FPU_REGS];
 };
@@ -161,7 +160,6 @@ struct thread_struct {
         */                                                     \
        .fpu                    = {                             \
                .fcsr           = 0,                            \
-               .vcsr           = 0,                            \
                .fcc            = 0,                            \
                .fpr            = {{{0,},},},                   \
        },                                                      \

diff --git a/arch/loongarch/kernel/asm-offsets.c b/arch/loongarch/kernel/asm-offsets.c
index bfb65eb..20cd9e1 100644 (file)
--- a/arch/loongarch/kernel/asm-offsets.c
+++ b/arch/loongarch/kernel/asm-offsets.c
@@ -166,7 +166,6 @@ void output_thread_fpu_defines(void)
 
        OFFSET(THREAD_FCSR, loongarch_fpu, fcsr);
        OFFSET(THREAD_FCC,  loongarch_fpu, fcc);
-       OFFSET(THREAD_VCSR, loongarch_fpu, vcsr);
        BLANK();
 }
 

diff --git a/arch/loongarch/kernel/fpu.S b/arch/loongarch/kernel/fpu.S
index 75c6ce0..a631a71 100644 (file)
--- a/arch/loongarch/kernel/fpu.S
+++ b/arch/loongarch/kernel/fpu.S
@@ -146,16 +146,6 @@
        movgr2fcsr      fcsr0, \tmp0
        .endm
 
-       .macro sc_save_vcsr base, tmp0
-       movfcsr2gr      \tmp0, vcsr16
-       EX      st.w \tmp0, \base, 0
-       .endm
-
-       .macro sc_restore_vcsr base, tmp0
-       EX      ld.w \tmp0, \base, 0
-       movgr2fcsr      vcsr16, \tmp0
-       .endm
-
 /*
  * Save a thread's fp context.
  */