1 files changed, 174 insertions, 0 deletions

diff --git a/arch/v850/kernel/v850e_cache.c b/arch/v850/kernel/v850e_cache.c
new file mode 100644
index 000000000000..ea3e51cfb259
--- /dev/null
+++ b/arch/v850/kernel/v850e_cache.c
@@ -0,0 +1,174 @@
+/*
+ * arch/v850/kernel/v850e_cache.c -- Cache control for V850E cache memories
+ *
+ *  Copyright (C) 2003  NEC Electronics Corporation
+ *  Copyright (C) 2003  Miles Bader <miles@gnu.org>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of this
+ * archive for more details.
+ *
+ * Written by Miles Bader <miles@gnu.org>
+ */
+
+/* This file implements cache control for the rather simple cache used on
+   some V850E CPUs, specifically the NB85E/TEG CPU-core and the V850E/ME2
+   CPU.  V850E2 processors have their own (better) cache
+   implementation.  */
+
+#include <asm/entry.h>
+#include <asm/cacheflush.h>
+#include <asm/v850e_cache.h>
+
+#define WAIT_UNTIL_CLEAR(value) while (value) {}
+
+/* Set caching params via the BHC and DCC registers.  */
+void v850e_cache_enable (u16 bhc, u16 icc, u16 dcc)
+{
+        unsigned long *r0_ram = (unsigned long *)R0_RAM_ADDR;
+        register u16 bhc_val asm ("r6") = bhc;
+
+        /* Read the instruction cache control register (ICC) and confirm
+           that bits 0 and 1 (TCLR0, TCLR1) are all cleared.  */
+        WAIT_UNTIL_CLEAR (V850E_CACHE_ICC & 0x3);
+        V850E_CACHE_ICC = icc;
+
+#ifdef V850E_CACHE_DCC
+        /* Configure data-cache.  */
+        V850E_CACHE_DCC = dcc;
+#endif /* V850E_CACHE_DCC */
+
+        /* Configure caching for various memory regions by writing the BHC
+           register.  The documentation says that an instruction _cannot_
+           enable/disable caching for the memory region in which the
+           instruction itself exists; to work around this, we store
+           appropriate instructions into the on-chip RAM area (which is never
+           cached), and briefly jump there to do the work.  */
+#ifdef V850E_CACHE_WRITE_IBS
+        *r0_ram++       = 0xf0720760;   /* st.h r0, 0xfffff072[r0] */
+#endif
+        *r0_ram++       = 0xf06a3760;   /* st.h r6, 0xfffff06a[r0] */
+        *r0_ram         = 0x5640006b;   /* jmp [r11] */
+
+        asm ("mov hilo(1f), r11; jmp [%1]; 1:;"
+             :: "r" (bhc_val), "r" (R0_RAM_ADDR) : "r11");
+}
+
+static void clear_icache (void)
+{
+        /* 1. Read the instruction cache control register (ICC) and confirm
+              that bits 0 and 1 (TCLR0, TCLR1) are all cleared.  */
+        WAIT_UNTIL_CLEAR (V850E_CACHE_ICC & 0x3);
+
+        /* 2. Read the ICC register and confirm that bit 12 (LOCK0) is
+              cleared.  Bit 13 of the ICC register is always cleared.  */
+        WAIT_UNTIL_CLEAR (V850E_CACHE_ICC & 0x1000);
+
+        /* 3. Set the TCLR0 and TCLR1 bits of the ICC register as follows,
+              when clearing way 0 and way 1 at the same time:
+                (a) Set the TCLR0 and TCLR1 bits.
+                (b) Read the TCLR0 and TCLR1 bits to confirm that these bits
+                    are cleared.
+                (c) Perform (a) and (b) above again.  */
+        V850E_CACHE_ICC |= 0x3;
+        WAIT_UNTIL_CLEAR (V850E_CACHE_ICC & 0x3);
+
+#ifdef V850E_CACHE_REPEAT_ICC_WRITE
+        /* Do it again.  */
+        V850E_CACHE_ICC |= 0x3;
+        WAIT_UNTIL_CLEAR (V850E_CACHE_ICC & 0x3);
+#endif
+}
+
+#ifdef V850E_CACHE_DCC
+/* Flush or clear (or both) the data cache, depending on the value of FLAGS;
+   the procedure is the same for both, just the control bits used differ (and
+   both may be performed simultaneously).  */
+static void dcache_op (unsigned short flags)
+{
+        /* 1. Read the data cache control register (DCC) and confirm that bits
+              0, 1, 4, and 5 (DC00, DC01, DC04, DC05) are all cleared.  */
+        WAIT_UNTIL_CLEAR (V850E_CACHE_DCC & 0x33);
+
+        /* 2. Clear DCC register bit 12 (DC12), bit 13 (DC13), or both
+              depending on the way for which tags are to be cleared.  */
+        V850E_CACHE_DCC &= ~0xC000;
+
+        /* 3. Set DCC register bit 0 (DC00), bit 1 (DC01) or both depending on
+              the way for which tags are to be cleared.
+              ...
+              Set DCC register bit 4 (DC04), bit 5 (DC05), or both depending
+              on the way to be data flushed.  */
+        V850E_CACHE_DCC |= flags;
+
+        /* 4. Read DCC register bit DC00, DC01 [DC04, DC05], or both depending
+              on the way for which tags were cleared [flushed] and confirm
+              that that bit is cleared.  */
+        WAIT_UNTIL_CLEAR (V850E_CACHE_DCC & flags);
+}
+#endif /* V850E_CACHE_DCC */
+
+/* Flushes the contents of the dcache to memory.  */
+static inline void flush_dcache (void)
+{
+#ifdef V850E_CACHE_DCC
+        /* We only need to do something if in write-back mode.  */
+        if (V850E_CACHE_DCC & 0x0400)
+                dcache_op (0x30);
+#endif /* V850E_CACHE_DCC */
+}
+
+/* Flushes the contents of the dcache to memory, and then clears it.  */
+static inline void clear_dcache (void)
+{
+#ifdef V850E_CACHE_DCC
+        /* We only need to do something if the dcache is enabled.  */
+        if (V850E_CACHE_DCC & 0x0C00)
+                dcache_op (0x33);
+#endif /* V850E_CACHE_DCC */
+}
+
+/* Clears the dcache without flushing to memory first.  */
+static inline void clear_dcache_no_flush (void)
+{
+#ifdef V850E_CACHE_DCC
+        /* We only need to do something if the dcache is enabled.  */
+        if (V850E_CACHE_DCC & 0x0C00)
+                dcache_op (0x3);
+#endif /* V850E_CACHE_DCC */
+}
+
+static inline void cache_exec_after_store (void)
+{
+        flush_dcache ();
+        clear_icache ();
+}
+
+
+/* Exported functions.  */
+
+void flush_icache (void)
+{
+        cache_exec_after_store ();
+}
+
+void flush_icache_range (unsigned long start, unsigned long end)
+{
+        cache_exec_after_store ();
+}
+
+void flush_icache_page (struct vm_area_struct *vma, struct page *page)
+{
+        cache_exec_after_store ();
+}
+
+void flush_icache_user_range (struct vm_area_struct *vma, struct page *page,
+                              unsigned long adr, int len)
+{
+        cache_exec_after_store ();
+}
+
+void flush_cache_sigtramp (unsigned long addr)
+{
+        cache_exec_after_store ();
+}