ARCv2: mm: Merge 2 updates to DC_CTRL for region flush
Region Flush has a weird programming model.
1. Flush or Invalidate is selected by DC_CTRL.RGN_OP
2 Flush-n-Invalidate is done by DC_CTRL.IM
Given the code structuring before, case #2 above was generating two
seperate updates to DC_CTRL which was pointless.
| 80a342b0 <__dma_cache_wback_inv_l1>:
| 80a342b0: clri r4
| 80a342b4: lr r2,[dc_ctrl]
| 80a342b8: bset_s r2,r2,0x6
| 80a342ba: sr r2,[dc_ctrl] <-- FIRST
|
| 80a342be: bmskn r3,r0,0x5
|
| 80a342c2: lr r2,[dc_ctrl]
| 80a342c6: and r2,r2,0xfffff1ff
| 80a342ce: bset_s r2,r2,0x9
| 80a342d0: sr r2,[dc_ctrl] <-- SECOND
|
| 80a342d4: add_s r1,r1,0x3f
| 80a342d6: bmsk_s r0,r0,0x5
| 80a342d8: add_s r0,r0,r1
| 80a342da: add_s r0,r0,r3
| 80a342dc: sr r0,[78]
| 80a342e0: sr r3,[77]
|...
|...
So move setting of DC_CTRL.RGN_OP into __before_dc_op() and combine with
any other update.
| 80b63324 <__dma_cache_wback_inv_l1>:
| 80b63324: clri r3
| 80b63328: lr r2,[dc_ctrl]
| 80b6332c: and r2,r2,0xfffff1ff
| 80b63334: or r2,r2,576
| 80b63338: sr r2,[dc_ctrl]
|
| 80b6333c: add_s r1,r1,0x3f
| 80b6333e: bmskn r2,r0,0x5
| 80b63342: add_s r0,r0,r1
| 80b63344: sr r0,[78]
| 80b63348: sr r2,[77]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index 8401fcb..a867575 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -409,8 +409,7 @@
void __cache_line_loop_v4(phys_addr_t paddr, unsigned long vaddr,
unsigned long sz, const int op, const int full_page)
{
- const unsigned int ctl = ARC_REG_DC_CTRL;
- unsigned int s, e, val;
+ unsigned int s, e;
/* Only for Non aliasing I-cache in HS38 */
if (op == OP_INV_IC) {
@@ -441,18 +440,6 @@
write_aux_reg(ARC_REG_DC_PTAG_HI, (u64)paddr >> 32);
}
- /*
- * Flush / Invalidate is provided by DC_CTRL.RNG_OP 0 or 1
- * Flush-n-invalidate additionally uses setting DC_CTRL.IM = 1
- * just as for line ops which is handled in __before_dc_op()
- */
- val = read_aux_reg(ctl) & ~DC_CTRL_RGN_OP_MSK;
-
- if (op & OP_INV)
- val |= DC_CTRL_RGN_OP_INV;
-
- write_aux_reg(ctl, val);
-
/* ENDR needs to be set ahead of START */
write_aux_reg(e, paddr + sz); /* ENDR is exclusive */
write_aux_reg(s, paddr);
@@ -476,6 +463,11 @@
* Machine specific helpers for Entire D-Cache or Per Line ops
*/
+#ifndef USE_RGN_FLSH
+/*
+ * this version avoids extra read/write of DC_CTRL for flush or invalid ops
+ * in the non region flush regime (such as for ARCompact)
+ */
static inline void __before_dc_op(const int op)
{
if (op == OP_FLUSH_N_INV) {
@@ -489,6 +481,32 @@
}
}
+#else
+
+static inline void __before_dc_op(const int op)
+{
+ const unsigned int ctl = ARC_REG_DC_CTRL;
+ unsigned int val = read_aux_reg(ctl);
+
+ if (op == OP_FLUSH_N_INV) {
+ val |= DC_CTRL_INV_MODE_FLUSH;
+ }
+
+ if (op != OP_INV_IC) {
+ /*
+ * Flush / Invalidate is provided by DC_CTRL.RNG_OP 0 or 1
+ * combined Flush-n-invalidate uses DC_CTRL.IM = 1 set above
+ */
+ val &= ~DC_CTRL_RGN_OP_MSK;
+ if (op & OP_INV)
+ val |= DC_CTRL_RGN_OP_INV;
+ }
+ write_aux_reg(ctl, val);
+}
+
+#endif
+
+
static inline void __after_dc_op(const int op)
{
if (op & OP_FLUSH) {