ARC: cacheflush: No need to retain DC_CTRL from __before_dc_op()

That is because __after_dc_op() already reads it for status check, so it
is better anyways to use that "newer" value.

Also reduces the clutter in callers for passing from/to these routines.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index 1ed3430..82d24c3 100644 (file)
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -207,32 +207,33 @@ static inline void __cache_line_loop(unsigned long paddr, unsigned long vaddr,
  * Machine specific helpers for Entire D-Cache or Per Line ops
  */
 
-static inline unsigned int __before_dc_op(const int op)
+static inline void __before_dc_op(const int op)
 {
-       unsigned int reg = reg;
-
        if (op == OP_FLUSH_N_INV) {
                /* Dcache provides 2 cmd: FLUSH or INV
                 * INV inturn has sub-modes: DISCARD or FLUSH-BEFORE
                 * flush-n-inv is achieved by INV cmd but with IM=1
                 * So toggle INV sub-mode depending on op request and default
                 */
-               reg = read_aux_reg(ARC_REG_DC_CTRL);
-               write_aux_reg(ARC_REG_DC_CTRL, reg | DC_CTRL_INV_MODE_FLUSH)
-                       ;
+               const unsigned int ctl = ARC_REG_DC_CTRL;
+               write_aux_reg(ctl, read_aux_reg(ctl) | DC_CTRL_INV_MODE_FLUSH);
        }
-
-       return reg;
 }
 
-static inline void __after_dc_op(const int op, unsigned int reg)
+static inline void __after_dc_op(const int op)
 {
-       if (op & OP_FLUSH)      /* flush / flush-n-inv both wait */
-               while (read_aux_reg(ARC_REG_DC_CTRL) & DC_CTRL_FLUSH_STATUS);
+       if (op & OP_FLUSH) {
+               const unsigned int ctl = ARC_REG_DC_CTRL;
+               unsigned int reg;
 
-       /* Switch back to default Invalidate mode */
-       if (op == OP_FLUSH_N_INV)
-               write_aux_reg(ARC_REG_DC_CTRL, reg & ~DC_CTRL_INV_MODE_FLUSH);
+               /* flush / flush-n-inv both wait */
+               while ((reg = read_aux_reg(ctl)) & DC_CTRL_FLUSH_STATUS)
+                       ;
+
+               /* Switch back to default Invalidate mode */
+               if (op == OP_FLUSH_N_INV)
+                       write_aux_reg(ctl, reg & ~DC_CTRL_INV_MODE_FLUSH);
+       }
 }
 
 /*
@@ -243,10 +244,9 @@ static inline void __after_dc_op(const int op, unsigned int reg)
  */
 static inline void __dc_entire_op(const int op)
 {
-       unsigned int ctrl_reg;
        int aux;
 
-       ctrl_reg = __before_dc_op(op);
+       __before_dc_op(op);
 
        if (op & OP_INV)        /* Inv or flush-n-inv use same cmd reg */
                aux = ARC_REG_DC_IVDC;
@@ -255,7 +255,7 @@ static inline void __dc_entire_op(const int op)
 
        write_aux_reg(aux, 0x1);
 
-       __after_dc_op(op, ctrl_reg);
+       __after_dc_op(op);
 }
 
 /* For kernel mappings cache operation: index is same as paddr */
@@ -268,15 +268,14 @@ static inline void __dc_line_op(unsigned long paddr, unsigned long vaddr,
                                unsigned long sz, const int op)
 {
        unsigned long flags;
-       unsigned int ctrl_reg;
 
        local_irq_save(flags);
 
-       ctrl_reg = __before_dc_op(op);
+       __before_dc_op(op);
 
        __cache_line_loop(paddr, vaddr, sz, op);
 
-       __after_dc_op(op, ctrl_reg);
+       __after_dc_op(op);
 
        local_irq_restore(flags);
 }