[PATCH] avr32 architecture
This adds support for the Atmel AVR32 architecture as well as the AT32AP7000
CPU and the AT32STK1000 development board.
AVR32 is a new high-performance 32-bit RISC microprocessor core, designed for
cost-sensitive embedded applications, with particular emphasis on low power
consumption and high code density. The AVR32 architecture is not binary
compatible with earlier 8-bit AVR architectures.
The AVR32 architecture, including the instruction set, is described by the
AVR32 Architecture Manual, available from
http://www.atmel.com/dyn/resources/prod_documents/doc32000.pdf
The Atmel AT32AP7000 is the first CPU implementing the AVR32 architecture. It
features a 7-stage pipeline, 16KB instruction and data caches and a full
Memory Management Unit. It also comes with a large set of integrated
peripherals, many of which are shared with the AT91 ARM-based controllers from
Atmel.
Full data sheet is available from
http://www.atmel.com/dyn/resources/prod_documents/doc32003.pdf
while the CPU core implementation including caches and MMU is documented by
the AVR32 AP Technical Reference, available from
http://www.atmel.com/dyn/resources/prod_documents/doc32001.pdf
Information about the AT32STK1000 development board can be found at
http://www.atmel.com/dyn/products/tools_card.asp?tool_id=3918
including a BSP CD image with an earlier version of this patch, development
tools (binaries and source/patches) and a root filesystem image suitable for
booting from SD card.
Alternatively, there's a preliminary "getting started" guide available at
http://avr32linux.org/twiki/bin/view/Main/GettingStarted which provides links
to the sources and patches you will need in order to set up a cross-compiling
environment for avr32-linux.
This patch, as well as the other patches included with the BSP and the
toolchain patches, is actively supported by Atmel Corporation.
[dmccr@us.ibm.com: Fix more pxx_page macro locations]
[bunk@stusta.de: fix `make defconfig']
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Dave McCracken <dmccr@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/asm-avr32/mmu_context.h b/include/asm-avr32/mmu_context.h
new file mode 100644
index 0000000..31add1a
--- /dev/null
+++ b/include/asm-avr32/mmu_context.h
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * ASID handling taken from SH implementation.
+ * Copyright (C) 1999 Niibe Yutaka
+ * Copyright (C) 2003 Paul Mundt
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __ASM_AVR32_MMU_CONTEXT_H
+#define __ASM_AVR32_MMU_CONTEXT_H
+
+#include <asm/tlbflush.h>
+#include <asm/pgalloc.h>
+#include <asm/sysreg.h>
+
+/*
+ * The MMU "context" consists of two things:
+ * (a) TLB cache version
+ * (b) ASID (Address Space IDentifier)
+ */
+#define MMU_CONTEXT_ASID_MASK 0x000000ff
+#define MMU_CONTEXT_VERSION_MASK 0xffffff00
+#define MMU_CONTEXT_FIRST_VERSION 0x00000100
+#define NO_CONTEXT 0
+
+#define MMU_NO_ASID 0x100
+
+/* Virtual Page Number mask */
+#define MMU_VPN_MASK 0xfffff000
+
+/* Cache of MMU context last used */
+extern unsigned long mmu_context_cache;
+
+/*
+ * Get MMU context if needed
+ */
+static inline void
+get_mmu_context(struct mm_struct *mm)
+{
+ unsigned long mc = mmu_context_cache;
+
+ if (((mm->context ^ mc) & MMU_CONTEXT_VERSION_MASK) == 0)
+ /* It's up to date, do nothing */
+ return;
+
+ /* It's old, we need to get new context with new version */
+ mc = ++mmu_context_cache;
+ if (!(mc & MMU_CONTEXT_ASID_MASK)) {
+ /*
+ * We have exhausted all ASIDs of this version.
+ * Flush the TLB and start new cycle.
+ */
+ flush_tlb_all();
+ /*
+ * Fix version. Note that we avoid version #0
+ * to distinguish NO_CONTEXT.
+ */
+ if (!mc)
+ mmu_context_cache = mc = MMU_CONTEXT_FIRST_VERSION;
+ }
+ mm->context = mc;
+}
+
+/*
+ * Initialize the context related info for a new mm_struct
+ * instance.
+ */
+static inline int init_new_context(struct task_struct *tsk,
+ struct mm_struct *mm)
+{
+ mm->context = NO_CONTEXT;
+ return 0;
+}
+
+/*
+ * Destroy context related info for an mm_struct that is about
+ * to be put to rest.
+ */
+static inline void destroy_context(struct mm_struct *mm)
+{
+ /* Do nothing */
+}
+
+static inline void set_asid(unsigned long asid)
+{
+ /* XXX: We're destroying TLBEHI[8:31] */
+ sysreg_write(TLBEHI, asid & MMU_CONTEXT_ASID_MASK);
+ cpu_sync_pipeline();
+}
+
+static inline unsigned long get_asid(void)
+{
+ unsigned long asid;
+
+ asid = sysreg_read(TLBEHI);
+ return asid & MMU_CONTEXT_ASID_MASK;
+}
+
+static inline void activate_context(struct mm_struct *mm)
+{
+ get_mmu_context(mm);
+ set_asid(mm->context & MMU_CONTEXT_ASID_MASK);
+}
+
+static inline void switch_mm(struct mm_struct *prev,
+ struct mm_struct *next,
+ struct task_struct *tsk)
+{
+ if (likely(prev != next)) {
+ unsigned long __pgdir = (unsigned long)next->pgd;
+
+ sysreg_write(PTBR, __pgdir);
+ activate_context(next);
+ }
+}
+
+#define deactivate_mm(tsk,mm) do { } while(0)
+
+#define activate_mm(prev, next) switch_mm((prev), (next), NULL)
+
+static inline void
+enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+}
+
+
+static inline void enable_mmu(void)
+{
+ sysreg_write(MMUCR, (SYSREG_BIT(MMUCR_S)
+ | SYSREG_BIT(E)
+ | SYSREG_BIT(MMUCR_I)));
+ nop(); nop(); nop(); nop(); nop(); nop(); nop(); nop();
+
+ if (mmu_context_cache == NO_CONTEXT)
+ mmu_context_cache = MMU_CONTEXT_FIRST_VERSION;
+
+ set_asid(mmu_context_cache & MMU_CONTEXT_ASID_MASK);
+}
+
+static inline void disable_mmu(void)
+{
+ sysreg_write(MMUCR, SYSREG_BIT(MMUCR_S));
+}
+
+#endif /* __ASM_AVR32_MMU_CONTEXT_H */