[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>

1 files changed, 335 insertions, 0 deletions

diff --git a/arch/avr32/kernel/setup.c b/arch/avr32/kernel/setup.c
new file mode 100644
index 00000000000..5d68f3c6990
--- /dev/null
+++ b/arch/avr32/kernel/setup.c
@@ -0,0 +1,335 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * 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.
+ */
+
+#include <linux/clk.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/console.h>
+#include <linux/ioport.h>
+#include <linux/bootmem.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/root_dev.h>
+#include <linux/cpu.h>
+
+#include <asm/sections.h>
+#include <asm/processor.h>
+#include <asm/pgtable.h>
+#include <asm/setup.h>
+#include <asm/sysreg.h>
+
+#include <asm/arch/board.h>
+#include <asm/arch/init.h>
+
+extern int root_mountflags;
+
+/*
+ * Bootloader-provided information about physical memory
+ */
+struct tag_mem_range *mem_phys;
+struct tag_mem_range *mem_reserved;
+struct tag_mem_range *mem_ramdisk;
+
+/*
+ * Initialize loops_per_jiffy as 5000000 (500MIPS).
+ * Better make it too large than too small...
+ */
+struct avr32_cpuinfo boot_cpu_data = {
+	.loops_per_jiffy = 5000000
+};
+EXPORT_SYMBOL(boot_cpu_data);
+
+static char command_line[COMMAND_LINE_SIZE];
+
+/*
+ * Should be more than enough, but if you have a _really_ complex
+ * setup, you might need to increase the size of this...
+ */
+static struct tag_mem_range __initdata mem_range_cache[32];
+static unsigned mem_range_next_free;
+
+/*
+ * Standard memory resources
+ */
+static struct resource mem_res[] = {
+	{
+		.name	= "Kernel code",
+		.start	= 0,
+		.end	= 0,
+		.flags	= IORESOURCE_MEM
+	},
+	{
+		.name	= "Kernel data",
+		.start	= 0,
+		.end	= 0,
+		.flags	= IORESOURCE_MEM,
+	},
+};
+
+#define kernel_code	mem_res[0]
+#define kernel_data	mem_res[1]
+
+/*
+ * Early framebuffer allocation. Works as follows:
+ *   - If fbmem_size is zero, nothing will be allocated or reserved.
+ *   - If fbmem_start is zero when setup_bootmem() is called,
+ *     fbmem_size bytes will be allocated from the bootmem allocator.
+ *   - If fbmem_start is nonzero, an area of size fbmem_size will be
+ *     reserved at the physical address fbmem_start if necessary. If
+ *     the area isn't in a memory region known to the kernel, it will
+ *     be left alone.
+ *
+ * Board-specific code may use these variables to set up platform data
+ * for the framebuffer driver if fbmem_size is nonzero.
+ */
+static unsigned long __initdata fbmem_start;
+static unsigned long __initdata fbmem_size;
+
+/*
+ * "fbmem=xxx[kKmM]" allocates the specified amount of boot memory for
+ * use as framebuffer.
+ *
+ * "fbmem=xxx[kKmM]@yyy[kKmM]" defines a memory region of size xxx and
+ * starting at yyy to be reserved for use as framebuffer.
+ *
+ * The kernel won't verify that the memory region starting at yyy
+ * actually contains usable RAM.
+ */
+static int __init early_parse_fbmem(char *p)
+{
+	fbmem_size = memparse(p, &p);
+	if (*p == '@')
+		fbmem_start = memparse(p, &p);
+	return 0;
+}
+early_param("fbmem", early_parse_fbmem);
+
+static inline void __init resource_init(void)
+{
+	struct tag_mem_range *region;
+
+	kernel_code.start = __pa(init_mm.start_code);
+	kernel_code.end = __pa(init_mm.end_code - 1);
+	kernel_data.start = __pa(init_mm.end_code);
+	kernel_data.end = __pa(init_mm.brk - 1);
+
+	for (region = mem_phys; region; region = region->next) {
+		struct resource *res;
+		unsigned long phys_start, phys_end;
+
+		if (region->size == 0)
+			continue;
+
+		phys_start = region->addr;
+		phys_end = phys_start + region->size - 1;
+
+		res = alloc_bootmem_low(sizeof(*res));
+		res->name = "System RAM";
+		res->start = phys_start;
+		res->end = phys_end;
+		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+
+		request_resource (&iomem_resource, res);
+
+		if (kernel_code.start >= res->start &&
+		    kernel_code.end <= res->end)
+			request_resource (res, &kernel_code);
+		if (kernel_data.start >= res->start &&
+		    kernel_data.end <= res->end)
+			request_resource (res, &kernel_data);
+	}
+}
+
+static int __init parse_tag_core(struct tag *tag)
+{
+	if (tag->hdr.size > 2) {
+		if ((tag->u.core.flags & 1) == 0)
+			root_mountflags &= ~MS_RDONLY;
+		ROOT_DEV = new_decode_dev(tag->u.core.rootdev);
+	}
+	return 0;
+}
+__tagtable(ATAG_CORE, parse_tag_core);
+
+static int __init parse_tag_mem_range(struct tag *tag,
+				      struct tag_mem_range **root)
+{
+	struct tag_mem_range *cur, **pprev;
+	struct tag_mem_range *new;
+
+	/*
+	 * Ignore zero-sized entries. If we're running standalone, the
+	 * SDRAM code may emit such entries if something goes
+	 * wrong...
+	 */
+	if (tag->u.mem_range.size == 0)
+		return 0;
+
+	/*
+	 * Copy the data so the bootmem init code doesn't need to care
+	 * about it.
+	 */
+	if (mem_range_next_free >=
+	    (sizeof(mem_range_cache) / sizeof(mem_range_cache[0])))
+		panic("Physical memory map too complex!\n");
+
+	new = &mem_range_cache[mem_range_next_free++];
+	*new = tag->u.mem_range;
+
+	pprev = root;
+	cur = *root;
+	while (cur) {
+		pprev = &cur->next;
+		cur = cur->next;
+	}
+
+	*pprev = new;
+	new->next = NULL;
+
+	return 0;
+}
+
+static int __init parse_tag_mem(struct tag *tag)
+{
+	return parse_tag_mem_range(tag, &mem_phys);
+}
+__tagtable(ATAG_MEM, parse_tag_mem);
+
+static int __init parse_tag_cmdline(struct tag *tag)
+{
+	strlcpy(saved_command_line, tag->u.cmdline.cmdline, COMMAND_LINE_SIZE);
+	return 0;
+}
+__tagtable(ATAG_CMDLINE, parse_tag_cmdline);
+
+static int __init parse_tag_rdimg(struct tag *tag)
+{
+	return parse_tag_mem_range(tag, &mem_ramdisk);
+}
+__tagtable(ATAG_RDIMG, parse_tag_rdimg);
+
+static int __init parse_tag_clock(struct tag *tag)
+{
+	/*
+	 * We'll figure out the clocks by peeking at the system
+	 * manager regs directly.
+	 */
+	return 0;
+}
+__tagtable(ATAG_CLOCK, parse_tag_clock);
+
+static int __init parse_tag_rsvd_mem(struct tag *tag)
+{
+	return parse_tag_mem_range(tag, &mem_reserved);
+}
+__tagtable(ATAG_RSVD_MEM, parse_tag_rsvd_mem);
+
+static int __init parse_tag_ethernet(struct tag *tag)
+{
+#if 0
+	const struct platform_device *pdev;
+
+	/*
+	 * We really need a bus type that supports "classes"...this
+	 * will do for now (until we must handle other kinds of
+	 * ethernet controllers)
+	 */
+	pdev = platform_get_device("macb", tag->u.ethernet.mac_index);
+	if (pdev && pdev->dev.platform_data) {
+		struct eth_platform_data *data = pdev->dev.platform_data;
+
+		data->valid = 1;
+		data->mii_phy_addr = tag->u.ethernet.mii_phy_addr;
+		memcpy(data->hw_addr, tag->u.ethernet.hw_address,
+		       sizeof(data->hw_addr));
+	}
+#endif
+	return 0;
+}
+__tagtable(ATAG_ETHERNET, parse_tag_ethernet);
+
+/*
+ * Scan the tag table for this tag, and call its parse function. The
+ * tag table is built by the linker from all the __tagtable
+ * declarations.
+ */
+static int __init parse_tag(struct tag *tag)
+{
+	extern struct tagtable __tagtable_begin, __tagtable_end;
+	struct tagtable *t;
+
+	for (t = &__tagtable_begin; t < &__tagtable_end; t++)
+		if (tag->hdr.tag == t->tag) {
+			t->parse(tag);
+			break;
+		}
+
+	return t < &__tagtable_end;
+}
+
+/*
+ * Parse all tags in the list we got from the boot loader
+ */
+static void __init parse_tags(struct tag *t)
+{
+	for (; t->hdr.tag != ATAG_NONE; t = tag_next(t))
+		if (!parse_tag(t))
+			printk(KERN_WARNING
+			       "Ignoring unrecognised tag 0x%08x\n",
+			       t->hdr.tag);
+}
+
+void __init setup_arch (char **cmdline_p)
+{
+	struct clk *cpu_clk;
+
+	parse_tags(bootloader_tags);
+
+	setup_processor();
+	setup_platform();
+
+	cpu_clk = clk_get(NULL, "cpu");
+	if (IS_ERR(cpu_clk)) {
+		printk(KERN_WARNING "Warning: Unable to get CPU clock\n");
+	} else {
+		unsigned long cpu_hz = clk_get_rate(cpu_clk);
+
+		/*
+		 * Well, duh, but it's probably a good idea to
+		 * increment the use count.
+		 */
+		clk_enable(cpu_clk);
+
+		boot_cpu_data.clk = cpu_clk;
+		boot_cpu_data.loops_per_jiffy = cpu_hz * 4;
+		printk("CPU: Running at %lu.%03lu MHz\n",
+		       ((cpu_hz + 500) / 1000) / 1000,
+		       ((cpu_hz + 500) / 1000) % 1000);
+	}
+
+	init_mm.start_code = (unsigned long) &_text;
+	init_mm.end_code = (unsigned long) &_etext;
+	init_mm.end_data = (unsigned long) &_edata;
+	init_mm.brk = (unsigned long) &_end;
+
+	strlcpy(command_line, saved_command_line, COMMAND_LINE_SIZE);
+	*cmdline_p = command_line;
+	parse_early_param();
+
+	setup_bootmem();
+
+	board_setup_fbmem(fbmem_start, fbmem_size);
+
+#ifdef CONFIG_VT
+	conswitchp = &dummy_con;
+#endif
+
+	paging_init();
+
+	resource_init();
+}