/*
 * (C) Copyright 2008 Openmoko, Inc.
 * Author: Andy Green <andy@openmoko.org>
 *
 * Parse the U-Boot header and Boot Linux
 * based on various code from U-Boot
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

#include <qi.h>
#include <neo_gta02.h>
#include "blink_led.h"
#include <string.h>
#define __ARM__
#include <image.h>
#include <setup.h>
#include "nand_read.h"
#include <ext2.h>

unsigned long partition_offset_blocks = 0;
unsigned long partition_length_blocks = 0;

struct kernel_source const * this_kernel = 0;


void bootloader_second_phase(void)
{
	void	(*the_kernel)(int zero, int arch, uint params);
	int kernel = 0;
	const struct board_variant * board_variant =
					      (this_board->get_board_variant)();

	/* we try the possible kernels for this board in order */

	this_kernel = &this_board->kernel_source[kernel++];

	while (this_kernel->name) {
		const char *p;
		struct tag *params = (struct tag *)this_board->linux_tag_placement;
		void * kernel_dram = (void *)(TEXT_BASE - (8 * 1024 * 1024));
		unsigned long crc;
		image_header_t	*hdr;
		u32 kernel_size;

		partition_offset_blocks = 0;
		partition_length_blocks = 0;

		/* eat leading white space */
		for (p = this_kernel->commandline; *p == ' '; p++);

		puts("\n\nTrying kernel: ");
		puts(this_kernel->name);
		puts("\n");

		/* if this device needs initializing, try to init it */
		if (this_kernel->block_init)
			if ((this_kernel->block_init)()) {
				puts("block device init failed\n");
				this_kernel = &this_board->
							kernel_source[kernel++];
				continue;
			}

		/* if there's a partition table implied, parse it, otherwise
		 * just use a fixed offset
		 */
		if (this_kernel->partition_index) {
			unsigned char *p = kernel_dram;

			if (this_kernel->block_read(kernel_dram, 0, 4) < 0) {
				puts("Bad partition read\n");
				this_kernel = &this_board->
							kernel_source[kernel++];
				continue;
			}

			if ((p[0x1fe] != 0x55) || (p[0x1ff] != 0xaa)) {
				puts("partition signature missing\n");
				this_kernel = &this_board->
							kernel_source[kernel++];
				continue;
			}

			p += 0x1be + 8 + (0x10 *
					    (this_kernel->partition_index - 1));

			partition_offset_blocks = (((u32)p[3]) << 24) |
						  (((u32)p[2]) << 16) |
						  (((u32)p[1]) << 8) |
						  p[0];
			partition_length_blocks = (((u32)p[7]) << 24) |
						  (((u32)p[6]) << 16) |
						  (((u32)p[5]) << 8) |
						  p[4];

			puts("    Partition: ");
			printdec(this_kernel->partition_index);
			puts(" start +");
			printdec(partition_offset_blocks);
			puts(" 512-byte blocks, size ");
			printdec(partition_length_blocks / 2048);
			puts(" MiB\n");

		} else
			partition_offset_blocks =
				  this_kernel->offset_blocks512_if_no_partition;

		switch (this_kernel->filesystem) {
		case FS_EXT2:
			if (!ext2fs_mount()) {
				puts("Unable to mount ext2 filesystem\n");
				this_kernel = &this_board->
							kernel_source[kernel++];
				continue;
			}
			puts("    EXT2 open: ");
			puts(this_kernel->filepath);
			puts("\n");
			if (ext2fs_open(this_kernel->filepath) < 0) {
				puts("Open failed\n");
				this_kernel = &this_board->
							kernel_source[kernel++];
				continue;
			}
			ext2fs_read(kernel_dram, 4096);
			break;
		case FS_FAT:
			/* FIXME */
		case FS_RAW:
			puts("     RAW open: +");
			printdec(partition_offset_blocks);
			puts(" 512-byte blocks\n");
			if (this_kernel->block_read(kernel_dram,
					      partition_offset_blocks, 8) < 0) {
				puts ("Bad kernel header\n");
				this_kernel = &this_board->
							kernel_source[kernel++];
				continue;
			}
			break;
		}

		hdr = (image_header_t *)kernel_dram;

		if (__be32_to_cpu(hdr->ih_magic) != IH_MAGIC) {
			puts("bad magic ");
			print32(hdr->ih_magic);
			puts("\n");
			this_kernel = &this_board->kernel_source[kernel++];
			continue;
		}

		puts("        Found: \"");
		puts((const char *)hdr->ih_name);
		puts("\"\n         Size: ");
		printdec(__be32_to_cpu(hdr->ih_size) >> 10);
		puts(" KiB\n");

		kernel_size = ((__be32_to_cpu(hdr->ih_size) +
				  sizeof(image_header_t) + 2048) & ~(2048 - 1));

		switch (this_kernel->filesystem) {
		case FS_EXT2:
			/* This read API always restarts from beginning */
			ext2fs_read(kernel_dram, kernel_size);
			break;
		case FS_FAT:
			/* FIXME */
		case FS_RAW:
			if ((this_kernel->block_read)(
				kernel_dram, partition_offset_blocks,
						kernel_size >> 9) < 0) {
				puts ("Bad kernel read\n");
				this_kernel = &this_board->
							kernel_source[kernel++];
				continue;
			}
			break;
		}

		puts("      Cmdline: ");
		puts(p);
		puts("\n");

		/*
		 * It's good for now to know that our kernel is intact from
		 * the storage before we jump into it and maybe crash silently
		 * even though it costs us some time
		 */
		crc = crc32(0, kernel_dram + sizeof(image_header_t),
						   __be32_to_cpu(hdr->ih_size));
		if (crc != __be32_to_cpu(hdr->ih_dcrc)) {
			puts("\nKernel CRC ERROR: read 0x");
			print32(crc);
			puts(" vs hdr CRC 0x");
			print32(__be32_to_cpu(hdr->ih_dcrc));
			puts("\n");
			this_kernel = &this_board->kernel_source[kernel++];
			continue;
		}

		the_kernel = (void (*)(int, int, uint))
					(((char *)hdr) + sizeof(image_header_t));

		/* first tag */
		params->hdr.tag = ATAG_CORE;
		params->hdr.size = tag_size (tag_core);
		params->u.core.flags = 0;
		params->u.core.pagesize = 0;
		params->u.core.rootdev = 0;
		params = tag_next(params);

		/* revision tag */
		params->hdr.tag = ATAG_REVISION;
		params->hdr.size = tag_size (tag_revision);
		params->u.revision.rev = board_variant->machine_revision;
		params = tag_next(params);

		/* memory tags */
		params->hdr.tag = ATAG_MEM;
		params->hdr.size = tag_size (tag_mem32);
		params->u.mem.start = this_board->linux_mem_start;
		params->u.mem.size = this_board->linux_mem_size;
		params = tag_next(params);

		/* kernel commandline */

		if (*p) {
			params->hdr.tag = ATAG_CMDLINE;
			params->hdr.size = (sizeof (struct tag_header) +
						       strlen (p) + 1 + 4) >> 2;
			strcpy (params->u.cmdline.cmdline, p);
			params = tag_next (params);
		}

		/* needs to always be the last tag */
		params->hdr.tag = ATAG_NONE;
		params->hdr.size = 0;

		puts ("Starting --->\n\n");

		/*
		* ooh that's it, we're gonna try boot this image!
		* never mind the cache, Linux will take care of it
		*/
		the_kernel(0, this_board->linux_machine_id,
						this_board->linux_tag_placement);

		/* we won't come back here no matter what */
	}

	/* none of the kernels worked out */

	puts("No usable kernel image found, we've had it  :-(\n");
	while (1)
		blue_on(1);
}