xref: /kernel/linux/linux-5.10/arch/powerpc/boot/wii.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * arch/powerpc/boot/wii.c
 *
 * Nintendo Wii bootwrapper support
 * Copyright (C) 2008-2009 The GameCube Linux Team
 * Copyright (C) 2008,2009 Albert Herranz
 */

#include <stddef.h>
#include "stdio.h"
#include "types.h"
#include "io.h"
#include "ops.h"

#include "ugecon.h"

BSS_STACK(8192);

#define HW_REG(x)		((void *)(x))

#define EXI_CTRL		HW_REG(0x0d800070)
#define EXI_CTRL_ENABLE		(1<<0)

#define MEM2_TOP		(0x10000000 + 64*1024*1024)
#define FIRMWARE_DEFAULT_SIZE	(12*1024*1024)


struct mipc_infohdr {
	char magic[3];
	u8 version;
	u32 mem2_boundary;
	u32 ipc_in;
	size_t ipc_in_size;
	u32 ipc_out;
	size_t ipc_out_size;
};

static int mipc_check_address(u32 pa)
{
	/* only MEM2 addresses */
	if (pa < 0x10000000 || pa > 0x14000000)
		return -EINVAL;
	return 0;
}

static struct mipc_infohdr *mipc_get_infohdr(void)
{
	struct mipc_infohdr **hdrp, *hdr;

	/* 'mini' header pointer is the last word of MEM2 memory */
	hdrp = (struct mipc_infohdr **)0x13fffffc;
	if (mipc_check_address((u32)hdrp)) {
		printf("mini: invalid hdrp %08X\n", (u32)hdrp);
		hdr = NULL;
		goto out;
	}

	hdr = *hdrp;
	if (mipc_check_address((u32)hdr)) {
		printf("mini: invalid hdr %08X\n", (u32)hdr);
		hdr = NULL;
		goto out;
	}
	if (memcmp(hdr->magic, "IPC", 3)) {
		printf("mini: invalid magic\n");
		hdr = NULL;
		goto out;
	}

out:
	return hdr;
}

static int mipc_get_mem2_boundary(u32 *mem2_boundary)
{
	struct mipc_infohdr *hdr;
	int error;

	hdr = mipc_get_infohdr();
	if (!hdr) {
		error = -1;
		goto out;
	}

	if (mipc_check_address(hdr->mem2_boundary)) {
		printf("mini: invalid mem2_boundary %08X\n",
		       hdr->mem2_boundary);
		error = -EINVAL;
		goto out;
	}
	*mem2_boundary = hdr->mem2_boundary;
	error = 0;
out:
	return error;

}

static void platform_fixups(void)
{
	void *mem;
	u32 reg[4];
	u32 mem2_boundary;
	int len;
	int error;

	mem = finddevice("/memory");
	if (!mem)
		fatal("Can't find memory node\n");

	/* two ranges of (address, size) words */
	len = getprop(mem, "reg", reg, sizeof(reg));
	if (len != sizeof(reg)) {
		/* nothing to do */
		goto out;
	}

	/* retrieve MEM2 boundary from 'mini' */
	error = mipc_get_mem2_boundary(&mem2_boundary);
	if (error) {
		/* if that fails use a sane value */
		mem2_boundary = MEM2_TOP - FIRMWARE_DEFAULT_SIZE;
	}

	if (mem2_boundary > reg[2] && mem2_boundary < reg[2] + reg[3]) {
		reg[3] = mem2_boundary - reg[2];
		printf("top of MEM2 @ %08X\n", reg[2] + reg[3]);
		setprop(mem, "reg", reg, sizeof(reg));
	}

out:
	return;
}

void platform_init(unsigned long r3, unsigned long r4, unsigned long r5)
{
	u32 heapsize = 24*1024*1024 - (u32)_end;

	simple_alloc_init(_end, heapsize, 32, 64);
	fdt_init(_dtb_start);

	/*
	 * 'mini' boots the Broadway processor with EXI disabled.
	 * We need it enabled before probing for the USB Gecko.
	 */
	out_be32(EXI_CTRL, in_be32(EXI_CTRL) | EXI_CTRL_ENABLE);

	if (ug_probe())
		console_ops.write = ug_console_write;

	platform_ops.fixups = platform_fixups;
}