ARC: Cache: Fix SLC operations when SLC is bypassed for data

If L1 D$ is disabled SLC is bypassed for data and all
load/store requests are sent directly to main memory.

If L1 I$ is disabled SLC is NOT bypassed for instructions
and all instruction requests are fetched through SLC.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

diff --git a/arch/arc/lib/cache.c b/arch/arc/lib/cache.c
index 7052895bb7209d20980c365ac045b12bbd34e3b4..a5aae3d232d96568f8850619c54d0b2806514fe5 100644 (file)
--- a/arch/arc/lib/cache.c
+++ b/arch/arc/lib/cache.c
@@ -168,6 +168,15 @@ static inline bool slc_exists(void)
        return false;
 }
 
+static inline bool slc_data_bypass(void)
+{
+       /*
+        * If L1 data cache is disabled SL$ is bypassed and all load/store
+        * requests are sent directly to main memory.
+        */
+       return !dcache_enabled();
+}
+
 static inline bool ioc_exists(void)
 {
        if (is_isa_arcv2()) {
@@ -412,7 +421,13 @@ void invalidate_icache_all(void)
 {
        __ic_entire_invalidate();
 
-       if (is_isa_arcv2())
+       /*
+        * If SL$ is bypassed for data it is used only for instructions,
+        * so we need to invalidate it too.
+        * TODO: HS 3.0 supports SLC disable so we need to check slc
+        * enable/disable status here.
+        */
+       if (is_isa_arcv2() && slc_data_bypass())
                __slc_entire_op(OP_INV);
 }
 
@@ -520,14 +535,15 @@ void invalidate_dcache_range(unsigned long start, unsigned long end)
                return;
 
        /*
-        * ARCv1                  -> call __dc_line_op
-        * ARCv2 && no IOC        -> call __dc_line_op; call __slc_rgn_op
-        * ARCv2 && IOC enabled   -> nothing
+        * ARCv1                                 -> call __dc_line_op
+        * ARCv2 && L1 D$ disabled               -> nothing
+        * ARCv2 && L1 D$ enabled && IOC enabled -> nothing
+        * ARCv2 && L1 D$ enabled && no IOC      -> call __dc_line_op; call __slc_rgn_op
         */
        if (!is_isa_arcv2() || !ioc_enabled())
                __dc_line_op(start, end - start, OP_INV);
 
-       if (is_isa_arcv2() && !ioc_enabled())
+       if (is_isa_arcv2() && !ioc_enabled() && !slc_data_bypass())
                __slc_rgn_op(start, end - start, OP_INV);
 }
 
@@ -537,14 +553,15 @@ void flush_dcache_range(unsigned long start, unsigned long end)
                return;
 
        /*
-        * ARCv1                  -> call __dc_line_op
-        * ARCv2 && no IOC        -> call __dc_line_op; call __slc_rgn_op
-        * ARCv2 && IOC enabled   -> nothing
+        * ARCv1                                 -> call __dc_line_op
+        * ARCv2 && L1 D$ disabled               -> nothing
+        * ARCv2 && L1 D$ enabled && IOC enabled -> nothing
+        * ARCv2 && L1 D$ enabled && no IOC      -> call __dc_line_op; call __slc_rgn_op
         */
        if (!is_isa_arcv2() || !ioc_enabled())
                __dc_line_op(start, end - start, OP_FLUSH);
 
-       if (is_isa_arcv2() && !ioc_enabled())
+       if (is_isa_arcv2() && !ioc_enabled() && !slc_data_bypass())
                __slc_rgn_op(start, end - start, OP_FLUSH);
 }
 
@@ -563,7 +580,7 @@ void flush_n_invalidate_dcache_all(void)
 {
        __dc_entire_op(OP_FLUSH_N_INV);
 
-       if (is_isa_arcv2())
+       if (is_isa_arcv2() && !slc_data_bypass())
                __slc_entire_op(OP_FLUSH_N_INV);
 }
 
@@ -571,6 +588,6 @@ void flush_dcache_all(void)
 {
        __dc_entire_op(OP_FLUSH);
 
-       if (is_isa_arcv2())
+       if (is_isa_arcv2() && !slc_data_bypass())
                __slc_entire_op(OP_FLUSH);
 }