[deliverable/linux.git] / arch / x86 / platform / olpc / olpc_dt.c

/*
 * OLPC-specific OFW device tree support code.
 *
 * Paul Mackerras	August 1996.
 * Copyright (C) 1996-2005 Paul Mackerras.
 *
 *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
 *    {engebret|bergner}@us.ibm.com
 *
 *  Adapted for sparc by David S. Miller davem@davemloft.net
 *  Adapted for x86/OLPC by Andres Salomon <dilinger@queued.net>
 *
 *      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.
 */

#include <linux/kernel.h>
#include <linux/bootmem.h>
#include <linux/of.h>
#include <linux/of_pdt.h>
#include <asm/olpc_ofw.h>

static phandle __init olpc_dt_getsibling(phandle node)
{
	const void *args[] = { (void *)node };
	void *res[] = { &node };

	if ((s32)node == -1)
		return 0;

	if (olpc_ofw("peer", args, res) || (s32)node == -1)
		return 0;

	return node;
}

static phandle __init olpc_dt_getchild(phandle node)
{
	const void *args[] = { (void *)node };
	void *res[] = { &node };

	if ((s32)node == -1)
		return 0;

	if (olpc_ofw("child", args, res) || (s32)node == -1) {
		pr_err("PROM: %s: fetching child failed!\n", __func__);
		return 0;
	}

	return node;
}

static int __init olpc_dt_getproplen(phandle node, const char *prop)
{
	const void *args[] = { (void *)node, prop };
	int len;
	void *res[] = { &len };

	if ((s32)node == -1)
		return -1;

	if (olpc_ofw("getproplen", args, res)) {
		pr_err("PROM: %s: getproplen failed!\n", __func__);
		return -1;
	}

	return len;
}

static int __init olpc_dt_getproperty(phandle node, const char *prop,
		char *buf, int bufsize)
{
	int plen;

	plen = olpc_dt_getproplen(node, prop);
	if (plen > bufsize || plen < 1) {
		return -1;
	} else {
		const void *args[] = { (void *)node, prop, buf, (void *)plen };
		void *res[] = { &plen };

		if (olpc_ofw("getprop", args, res)) {
			pr_err("PROM: %s: getprop failed!\n", __func__);
			return -1;
		}
	}

	return plen;
}

static int __init olpc_dt_nextprop(phandle node, char *prev, char *buf)
{
	const void *args[] = { (void *)node, prev, buf };
	int success;
	void *res[] = { &success };

	buf[0] = '\0';

	if ((s32)node == -1)
		return -1;

	if (olpc_ofw("nextprop", args, res) || success != 1)
		return -1;

	return 0;
}

static int __init olpc_dt_pkg2path(phandle node, char *buf,
		const int buflen, int *len)
{
	const void *args[] = { (void *)node, buf, (void *)buflen };
	void *res[] = { len };

	if ((s32)node == -1)
		return -1;

	if (olpc_ofw("package-to-path", args, res) || *len < 1)
		return -1;

	return 0;
}

static unsigned int prom_early_allocated __initdata;

void * __init prom_early_alloc(unsigned long size)
{
	static u8 *mem;
	static size_t free_mem;
	void *res;

	if (free_mem < size) {
		const size_t chunk_size = max(PAGE_SIZE, size);

		/*
		 * To mimimize the number of allocations, grab at least
		 * PAGE_SIZE of memory (that's an arbitrary choice that's
		 * fast enough on the platforms we care about while minimizing
		 * wasted bootmem) and hand off chunks of it to callers.
		 */
		res = alloc_bootmem(chunk_size);
		BUG_ON(!res);
		prom_early_allocated += chunk_size;
		memset(res, 0, chunk_size);
		free_mem = chunk_size;
		mem = res;
	}

	/* allocate from the local cache */
	free_mem -= size;
	res = mem;
	mem += size;
	return res;
}

static struct of_pdt_ops prom_olpc_ops __initdata = {
	.nextprop = olpc_dt_nextprop,
	.getproplen = olpc_dt_getproplen,
	.getproperty = olpc_dt_getproperty,
	.getchild = olpc_dt_getchild,
	.getsibling = olpc_dt_getsibling,
	.pkg2path = olpc_dt_pkg2path,
};

void __init olpc_dt_build_devicetree(void)
{
	phandle root;

	if (!olpc_ofw_is_installed())
		return;

	root = olpc_dt_getsibling(0);
	if (!root) {
		pr_err("PROM: unable to get root node from OFW!\n");
		return;
	}
	of_pdt_build_devicetree(root, &prom_olpc_ops);

	pr_info("PROM DT: Built device tree with %u bytes of memory.\n",
			prom_early_allocated);
}
Commit	Line	Data
c10d1e26 AS	1	/*
	2	* OLPC-specific OFW device tree support code.
	3	*
	4	* Paul Mackerras August 1996.
	5	* Copyright (C) 1996-2005 Paul Mackerras.
	6	*
	7	* Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
	8	* {engebret\|bergner}@us.ibm.com
	9	*
	10	* Adapted for sparc by David S. Miller davem@davemloft.net
	11	* Adapted for x86/OLPC by Andres Salomon <dilinger@queued.net>
	12	*
	13	* This program is free software; you can redistribute it and/or
	14	* modify it under the terms of the GNU General Public License
	15	* as published by the Free Software Foundation; either version
	16	* 2 of the License, or (at your option) any later version.
	17	*/
	18
	19	#include <linux/kernel.h>
	20	#include <linux/bootmem.h>
	21	#include <linux/of.h>
	22	#include <linux/of_pdt.h>
	23	#include <asm/olpc_ofw.h>
	24
	25	static phandle __init olpc_dt_getsibling(phandle node)
	26	{
	27	const void args[] = { (void )node };
	28	void *res[] = { &node };
	29
	30	if ((s32)node == -1)
	31	return 0;
	32
	33	if (olpc_ofw("peer", args, res) \|\| (s32)node == -1)
	34	return 0;
	35
	36	return node;
	37	}
	38
	39	static phandle __init olpc_dt_getchild(phandle node)
	40	{
	41	const void args[] = { (void )node };
	42	void *res[] = { &node };
	43
	44	if ((s32)node == -1)
	45	return 0;
	46
	47	if (olpc_ofw("child", args, res) \|\| (s32)node == -1) {
	48	pr_err("PROM: %s: fetching child failed!\n", __func__);
	49	return 0;
	50	}
	51
	52	return node;
	53	}
	54
	55	static int __init olpc_dt_getproplen(phandle node, const char *prop)
	56	{
	57	const void args[] = { (void )node, prop };
	58	int len;
	59	void *res[] = { &len };
	60
	61	if ((s32)node == -1)
	62	return -1;
	63
	64	if (olpc_ofw("getproplen", args, res)) {
65	pr_err("PROM: %s: getproplen failed!\n", __func__);
66	return -1;
67	}
68
69	return len;
70	}
71
72	static int __init olpc_dt_getproperty(phandle node, const char *prop,
73	char *buf, int bufsize)
74	{
75	int plen;
76
77	plen = olpc_dt_getproplen(node, prop);
78	if (plen > bufsize \|\| plen < 1) {
79	return -1;
80	} else {
81	const void args[] = { (void )node, prop, buf, (void *)plen };
82	void *res[] = { &plen };
83
84	if (olpc_ofw("getprop", args, res)) {
85	pr_err("PROM: %s: getprop failed!\n", __func__);
86	return -1;
87	}
88	}
89
90	return plen;
91	}
92
93	static int __init olpc_dt_nextprop(phandle node, char prev, char buf)
94	{
95	const void args[] = { (void )node, prev, buf };
96	int success;
97	void *res[] = { &success };
98
99	buf[0] = '\0';
100
101	if ((s32)node == -1)
102	return -1;
103
104	if (olpc_ofw("nextprop", args, res) \|\| success != 1)
105	return -1;
106
107	return 0;
108	}
109
110	static int __init olpc_dt_pkg2path(phandle node, char *buf,
111	const int buflen, int *len)
112	{
113	const void args[] = { (void )node, buf, (void *)buflen };
114	void *res[] = { len };
115
116	if ((s32)node == -1)
117	return -1;
118
119	if (olpc_ofw("package-to-path", args, res) \|\| *len < 1)
120	return -1;
121
122	return 0;
123	}
124
125	static unsigned int prom_early_allocated __initdata;
126
127	void * __init prom_early_alloc(unsigned long size)
128	{
b5318d30 AS	129	static u8 *mem;
b5318d30 AS	130	static size_t free_mem;
c10d1e26 AS	131	void *res;
c10d1e26 AS	132
b5318d30 AS	133	if (free_mem < size) {
	134	const size_t chunk_size = max(PAGE_SIZE, size);
	135
	136	/*
	137	* To mimimize the number of allocations, grab at least
	138	* PAGE_SIZE of memory (that's an arbitrary choice that's
	139	* fast enough on the platforms we care about while minimizing
	140	* wasted bootmem) and hand off chunks of it to callers.
	141	*/
	142	res = alloc_bootmem(chunk_size);
60cba5a5	143	BUG_ON(!res);
b5318d30 AS	144	prom_early_allocated += chunk_size;
	145	memset(res, 0, chunk_size);
	146	free_mem = chunk_size;
	147	mem = res;
	148	}
c10d1e26	149
b5318d30 AS	150	/* allocate from the local cache */
	151	free_mem -= size;
	152	res = mem;
	153	mem += size;
c10d1e26 AS	154	return res;
	155	}
	156
	157	static struct of_pdt_ops prom_olpc_ops __initdata = {
	158	.nextprop = olpc_dt_nextprop,
	159	.getproplen = olpc_dt_getproplen,
	160	.getproperty = olpc_dt_getproperty,
	161	.getchild = olpc_dt_getchild,
	162	.getsibling = olpc_dt_getsibling,
	163	.pkg2path = olpc_dt_pkg2path,
	164	};
	165
	166	void __init olpc_dt_build_devicetree(void)
	167	{
	168	phandle root;
	169
	170	if (!olpc_ofw_is_installed())
	171	return;
	172
	173	root = olpc_dt_getsibling(0);
	174	if (!root) {
	175	pr_err("PROM: unable to get root node from OFW!\n");
	176	return;
	177	}
	178	of_pdt_build_devicetree(root, &prom_olpc_ops);
	179
	180	pr_info("PROM DT: Built device tree with %u bytes of memory.\n",
	181	prom_early_allocated);
	182	}