From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?=
 <emulatorman@parabola.nu>
Date: Wed, 5 Aug 2015 17:04:01 -0300
Subject: Initial import

---
 arch/score/include/asm/fixmap.h | 82 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)
 create mode 100644 arch/score/include/asm/fixmap.h

(limited to 'arch/score/include/asm/fixmap.h')

diff --git a/arch/score/include/asm/fixmap.h b/arch/score/include/asm/fixmap.h
new file mode 100644
index 000000000..ee1676694
--- /dev/null
+++ b/arch/score/include/asm/fixmap.h
@@ -0,0 +1,82 @@
+#ifndef _ASM_SCORE_FIXMAP_H
+#define _ASM_SCORE_FIXMAP_H
+
+#include <asm/page.h>
+
+#define PHY_RAM_BASE		0x00000000
+#define PHY_IO_BASE		0x10000000
+
+#define VIRTUAL_RAM_BASE	0xa0000000
+#define VIRTUAL_IO_BASE		0xb0000000
+
+#define RAM_SPACE_SIZE		0x10000000
+#define IO_SPACE_SIZE		0x10000000
+
+/* Kernel unmapped, cached 512MB */
+#define KSEG1			0xa0000000
+
+/*
+ * Here we define all the compile-time 'special' virtual
+ * addresses. The point is to have a constant address at
+ * compile time, but to set the physical address only
+ * in the boot process. We allocate these special addresses
+ * from the end of virtual memory (0xfffff000) backwards.
+ * Also this lets us do fail-safe vmalloc(), we
+ * can guarantee that these special addresses and
+ * vmalloc()-ed addresses never overlap.
+ *
+ * these 'compile-time allocated' memory buffers are
+ * fixed-size 4k pages. (or larger if used with an increment
+ * highger than 1) use fixmap_set(idx,phys) to associate
+ * physical memory with fixmap indices.
+ *
+ * TLB entries of such buffers will not be flushed across
+ * task switches.
+ */
+
+/*
+ * on UP currently we will have no trace of the fixmap mechanizm,
+ * no page table allocations, etc. This might change in the
+ * future, say framebuffers for the console driver(s) could be
+ * fix-mapped?
+ */
+enum fixed_addresses {
+#define FIX_N_COLOURS 8
+	FIX_CMAP_BEGIN,
+	FIX_CMAP_END = FIX_CMAP_BEGIN + FIX_N_COLOURS,
+	__end_of_fixed_addresses
+};
+
+/*
+ * used by vmalloc.c.
+ *
+ * Leave one empty page between vmalloc'ed areas and
+ * the start of the fixmap, and leave one page empty
+ * at the top of mem..
+ */
+#define FIXADDR_TOP	((unsigned long)(long)(int)0xfefe0000)
+#define FIXADDR_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)
+#define FIXADDR_START	(FIXADDR_TOP - FIXADDR_SIZE)
+
+#define __fix_to_virt(x)	(FIXADDR_TOP - ((x) << PAGE_SHIFT))
+#define __virt_to_fix(x)	\
+	((FIXADDR_TOP - ((x) & PAGE_MASK)) >> PAGE_SHIFT)
+
+extern void __this_fixmap_does_not_exist(void);
+
+/*
+ * 'index to address' translation. If anyone tries to use the idx
+ * directly without tranlation, we catch the bug with a NULL-deference
+ * kernel oops. Illegal ranges of incoming indices are caught too.
+ */
+static inline unsigned long fix_to_virt(const unsigned int idx)
+{
+	return __fix_to_virt(idx);
+}
+
+static inline unsigned long virt_to_fix(const unsigned long vaddr)
+{
+	return __virt_to_fix(vaddr);
+}
+
+#endif /* _ASM_SCORE_FIXMAP_H */
-- 
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