sh: Support fixed 32-bit PMB mappings from bootloader.

This provides a method for supporting fixed PMB mappings inherited from
the bootloader, as an alternative to the dynamic PMB mapping currently
used by the kernel. In the future these methods will be combined.

P1/P2 area is handled like a regular 29-bit physical address, and local
bus device are assigned P3 area addresses.

Signed-off-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 45 insertions, 0 deletions

diff --git a/arch/sh/mm/pmb-fixed.c b/arch/sh/mm/pmb-fixed.c
new file mode 100644
index 000000000000..43c8eac4d8a1
--- /dev/null
+++ b/arch/sh/mm/pmb-fixed.c
@@ -0,0 +1,45 @@
+/*
+ * arch/sh/mm/fixed_pmb.c
+ *
+ * Copyright (C) 2009  Renesas Solutions Corp.
+ *
+ * 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.
+ */
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/io.h>
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+
+static int __uses_jump_to_uncached fixed_pmb_init(void)
+{
+	int i;
+	unsigned long addr, data;
+
+	jump_to_uncached();
+
+	for (i = 0; i < PMB_ENTRY_MAX; i++) {
+		addr = PMB_DATA + (i << PMB_E_SHIFT);
+		data = ctrl_inl(addr);
+		if (!(data & PMB_V))
+			continue;
+
+		if (data & PMB_C) {
+#if defined(CONFIG_CACHE_WRITETHROUGH)
+			data |= PMB_WT;
+#elif defined(CONFIG_CACHE_WRITEBACK)
+			data &= ~PMB_WT;
+#else
+			data &= ~(PMB_C | PMB_WT);
+#endif
+		}
+		ctrl_outl(data, addr);
+	}
+
+	back_to_cached();
+
+	return 0;
+}
+arch_initcall(fixed_pmb_init);