ARCv2: mm: Implement cache region flush operations
These are more efficient than the per-line ops
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index 18132eb..8401fcb 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -21,6 +21,10 @@
#include <asm/cachectl.h>
#include <asm/setup.h>
+#ifdef CONFIG_ISA_ARCV2
+#define USE_RGN_FLSH 1
+#endif
+
static int l2_line_sz;
static int ioc_exists;
int slc_enable = 1, ioc_enable = 1;
@@ -332,6 +336,8 @@
}
}
+#ifndef USE_RGN_FLSH
+
/*
* In HS38x (MMU v4), I-cache is VIPT (can alias), D-cache is PIPT
* Here's how cache ops are implemented
@@ -394,6 +400,68 @@
}
}
+#else
+
+/*
+ * optimized flush operation which takes a region as opposed to iterating per line
+ */
+static inline
+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;
+
+ /* Only for Non aliasing I-cache in HS38 */
+ if (op == OP_INV_IC) {
+ s = ARC_REG_IC_IVIR;
+ e = ARC_REG_IC_ENDR;
+ } else {
+ s = ARC_REG_DC_STARTR;
+ e = ARC_REG_DC_ENDR;
+ }
+
+ if (!full_page) {
+ /* for any leading gap between @paddr and start of cache line */
+ sz += paddr & ~CACHE_LINE_MASK;
+ paddr &= CACHE_LINE_MASK;
+
+ /*
+ * account for any trailing gap to end of cache line
+ * this is equivalent to DIV_ROUND_UP() in line ops above
+ */
+ sz += L1_CACHE_BYTES - 1;
+ }
+
+ if (is_pae40_enabled()) {
+ /* TBD: check if crossing 4TB boundary */
+ if (op == OP_INV_IC)
+ write_aux_reg(ARC_REG_IC_PTAG_HI, (u64)paddr >> 32);
+ else
+ 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);
+
+ /* caller waits on DC_CTRL.FS */
+}
+
+#endif
+
#if (CONFIG_ARC_MMU_VER < 3)
#define __cache_line_loop __cache_line_loop_v2
#elif (CONFIG_ARC_MMU_VER == 3)