[mirror_ubuntu-bionic-kernel.git] / drivers / tty / hvc / hvc_opal.c

/*
 * opal driver interface to hvc_console.c
 *
 * Copyright 2011 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
 *
 * 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
 *
 */

#undef DEBUG

#include <linux/types.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/console.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/export.h>

#include <asm/hvconsole.h>
#include <asm/prom.h>
#include <asm/firmware.h>
#include <asm/hvsi.h>
#include <asm/udbg.h>
#include <asm/opal.h>

#include "hvc_console.h"

static const char hvc_opal_name[] = "hvc_opal";

static struct of_device_id hvc_opal_match[] __devinitdata = {
	{ .name = "serial", .compatible = "ibm,opal-console-raw" },
	{ .name = "serial", .compatible = "ibm,opal-console-hvsi" },
	{ },
};

typedef enum hv_protocol {
	HV_PROTOCOL_RAW,
	HV_PROTOCOL_HVSI
} hv_protocol_t;

struct hvc_opal_priv {
	hv_protocol_t		proto;	/* Raw data or HVSI packets */
	struct hvsi_priv	hvsi;	/* HVSI specific data */
};
static struct hvc_opal_priv *hvc_opal_privs[MAX_NR_HVC_CONSOLES];

/* For early boot console */
static struct hvc_opal_priv hvc_opal_boot_priv;
static u32 hvc_opal_boot_termno;

static const struct hv_ops hvc_opal_raw_ops = {
	.get_chars = opal_get_chars,
	.put_chars = opal_put_chars,
	.notifier_add = notifier_add_irq,
	.notifier_del = notifier_del_irq,
	.notifier_hangup = notifier_hangup_irq,
};

static int hvc_opal_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
{
	struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];

	if (WARN_ON(!pv))
		return -ENODEV;

	return hvsilib_get_chars(&pv->hvsi, buf, count);
}

static int hvc_opal_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
{
	struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];

	if (WARN_ON(!pv))
		return -ENODEV;

	return hvsilib_put_chars(&pv->hvsi, buf, count);
}

static int hvc_opal_hvsi_open(struct hvc_struct *hp, int data)
{
	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
	int rc;

	pr_devel("HVSI@%x: do open !\n", hp->vtermno);

	rc = notifier_add_irq(hp, data);
	if (rc)
		return rc;

	return hvsilib_open(&pv->hvsi, hp);
}

static void hvc_opal_hvsi_close(struct hvc_struct *hp, int data)
{
	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];

	pr_devel("HVSI@%x: do close !\n", hp->vtermno);

	hvsilib_close(&pv->hvsi, hp);

	notifier_del_irq(hp, data);
}

void hvc_opal_hvsi_hangup(struct hvc_struct *hp, int data)
{
	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];

	pr_devel("HVSI@%x: do hangup !\n", hp->vtermno);

	hvsilib_close(&pv->hvsi, hp);

	notifier_hangup_irq(hp, data);
}

static int hvc_opal_hvsi_tiocmget(struct hvc_struct *hp)
{
	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];

	if (!pv)
		return -EINVAL;
	return pv->hvsi.mctrl;
}

static int hvc_opal_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set,
				unsigned int clear)
{
	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];

	pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n",
		 hp->vtermno, set, clear);

	if (set & TIOCM_DTR)
		hvsilib_write_mctrl(&pv->hvsi, 1);
	else if (clear & TIOCM_DTR)
		hvsilib_write_mctrl(&pv->hvsi, 0);

	return 0;
}

static const struct hv_ops hvc_opal_hvsi_ops = {
	.get_chars = hvc_opal_hvsi_get_chars,
	.put_chars = hvc_opal_hvsi_put_chars,
	.notifier_add = hvc_opal_hvsi_open,
	.notifier_del = hvc_opal_hvsi_close,
	.notifier_hangup = hvc_opal_hvsi_hangup,
	.tiocmget = hvc_opal_hvsi_tiocmget,
	.tiocmset = hvc_opal_hvsi_tiocmset,
};

static int __devinit hvc_opal_probe(struct platform_device *dev)
{
	const struct hv_ops *ops;
	struct hvc_struct *hp;
	struct hvc_opal_priv *pv;
	hv_protocol_t proto;
	unsigned int termno, boot = 0;
	const __be32 *reg;

	if (of_device_is_compatible(dev->dev.of_node, "ibm,opal-console-raw")) {
		proto = HV_PROTOCOL_RAW;
		ops = &hvc_opal_raw_ops;
	} else if (of_device_is_compatible(dev->dev.of_node,
					   "ibm,opal-console-hvsi")) {
		proto = HV_PROTOCOL_HVSI;
		ops = &hvc_opal_hvsi_ops;
	} else {
		pr_err("hvc_opal: Unkown protocol for %s\n",
		       dev->dev.of_node->full_name);
		return -ENXIO;
	}

	reg = of_get_property(dev->dev.of_node, "reg", NULL);
	termno = reg ? be32_to_cpup(reg) : 0;

	/* Is it our boot one ? */
	if (hvc_opal_privs[termno] == &hvc_opal_boot_priv) {
		pv = hvc_opal_privs[termno];
		boot = 1;
	} else if (hvc_opal_privs[termno] == NULL) {
		pv = kzalloc(sizeof(struct hvc_opal_priv), GFP_KERNEL);
		if (!pv)
			return -ENOMEM;
		pv->proto = proto;
		hvc_opal_privs[termno] = pv;
		if (proto == HV_PROTOCOL_HVSI)
			hvsilib_init(&pv->hvsi, opal_get_chars, opal_put_chars,
				     termno, 0);

		/* Instanciate now to establish a mapping index==vtermno */
		hvc_instantiate(termno, termno, ops);
	} else {
		pr_err("hvc_opal: Device %s has duplicate terminal number #%d\n",
		       dev->dev.of_node->full_name, termno);
		return -ENXIO;
	}

	pr_info("hvc%d: %s protocol on %s%s\n", termno,
		proto == HV_PROTOCOL_RAW ? "raw" : "hvsi",
		dev->dev.of_node->full_name,
		boot ? " (boot console)" : "");

	/* We don't do IRQ yet */
	hp = hvc_alloc(termno, 0, ops, MAX_VIO_PUT_CHARS);
	if (IS_ERR(hp))
		return PTR_ERR(hp);
	dev_set_drvdata(&dev->dev, hp);

	return 0;
}

static int __devexit hvc_opal_remove(struct platform_device *dev)
{
	struct hvc_struct *hp = dev_get_drvdata(&dev->dev);
	int rc, termno;

	termno = hp->vtermno;
	rc = hvc_remove(hp);
	if (rc == 0) {
		if (hvc_opal_privs[termno] != &hvc_opal_boot_priv)
			kfree(hvc_opal_privs[termno]);
		hvc_opal_privs[termno] = NULL;
	}
	return rc;
}

static struct platform_driver hvc_opal_driver = {
	.probe		= hvc_opal_probe,
	.remove		= __devexit_p(hvc_opal_remove),
	.driver		= {
		.name	= hvc_opal_name,
		.owner	= THIS_MODULE,
		.of_match_table	= hvc_opal_match,
	}
};

static int __init hvc_opal_init(void)
{
	if (!firmware_has_feature(FW_FEATURE_OPAL))
		return -ENODEV;

	/* Register as a vio device to receive callbacks */
	return platform_driver_register(&hvc_opal_driver);
}
module_init(hvc_opal_init);

static void __exit hvc_opal_exit(void)
{
	platform_driver_unregister(&hvc_opal_driver);
}
module_exit(hvc_opal_exit);

static void udbg_opal_putc(char c)
{
	unsigned int termno = hvc_opal_boot_termno;
	int count = -1;

	if (c == '\n')
		udbg_opal_putc('\r');

	do {
		switch(hvc_opal_boot_priv.proto) {
		case HV_PROTOCOL_RAW:
			count = opal_put_chars(termno, &c, 1);
			break;
		case HV_PROTOCOL_HVSI:
			count = hvc_opal_hvsi_put_chars(termno, &c, 1);
			break;
		}
	} while(count == 0 || count == -EAGAIN);
}

static int udbg_opal_getc_poll(void)
{
	unsigned int termno = hvc_opal_boot_termno;
	int rc = 0;
	char c;

	switch(hvc_opal_boot_priv.proto) {
	case HV_PROTOCOL_RAW:
		rc = opal_get_chars(termno, &c, 1);
		break;
	case HV_PROTOCOL_HVSI:
		rc = hvc_opal_hvsi_get_chars(termno, &c, 1);
		break;
	}
	if (!rc)
		return -1;
	return c;
}

static int udbg_opal_getc(void)
{
	int ch;
	for (;;) {
		ch = udbg_opal_getc_poll();
		if (ch == -1) {
			/* This shouldn't be needed...but... */
			volatile unsigned long delay;
			for (delay=0; delay < 2000000; delay++)
				;
		} else {
			return ch;
		}
	}
}

static void udbg_init_opal_common(void)
{
	udbg_putc = udbg_opal_putc;
	udbg_getc = udbg_opal_getc;
	udbg_getc_poll = udbg_opal_getc_poll;
	tb_ticks_per_usec = 0x200; /* Make udelay not suck */
}

void __init hvc_opal_init_early(void)
{
	struct device_node *stdout_node = NULL;
	const u32 *termno;
	const char *name = NULL;
	const struct hv_ops *ops;
	u32 index;

	/* find the boot console from /chosen/stdout */
	if (of_chosen)
		name = of_get_property(of_chosen, "linux,stdout-path", NULL);
	if (name) {
		stdout_node = of_find_node_by_path(name);
		if (!stdout_node) {
			pr_err("hvc_opal: Failed to locate default console!\n");
			return;
		}
	} else {
		struct device_node *opal, *np;

		/* Current OPAL takeover doesn't provide the stdout
		 * path, so we hard wire it
		 */
		opal = of_find_node_by_path("/ibm,opal/consoles");
		if (opal)
			pr_devel("hvc_opal: Found consoles in new location\n");
		if (!opal) {
			opal = of_find_node_by_path("/ibm,opal");
			if (opal)
				pr_devel("hvc_opal: "
					 "Found consoles in old location\n");
		}
		if (!opal)
			return;
		for_each_child_of_node(opal, np) {
			if (!strcmp(np->name, "serial")) {
				stdout_node = np;
				break;
			}
		}
		of_node_put(opal);
	}
	if (!stdout_node)
		return;
	termno = of_get_property(stdout_node, "reg", NULL);
	index = termno ? *termno : 0;
	if (index >= MAX_NR_HVC_CONSOLES)
		return;
	hvc_opal_privs[index] = &hvc_opal_boot_priv;

	/* Check the protocol */
	if (of_device_is_compatible(stdout_node, "ibm,opal-console-raw")) {
		hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
		ops = &hvc_opal_raw_ops;
		pr_devel("hvc_opal: Found RAW console\n");
	}
	else if (of_device_is_compatible(stdout_node,"ibm,opal-console-hvsi")) {
		hvc_opal_boot_priv.proto = HV_PROTOCOL_HVSI;
		ops = &hvc_opal_hvsi_ops;
		hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars,
			     opal_put_chars, index, 1);
		/* HVSI, perform the handshake now */
		hvsilib_establish(&hvc_opal_boot_priv.hvsi);
		pr_devel("hvc_opal: Found HVSI console\n");
	} else
		goto out;
	hvc_opal_boot_termno = index;
	udbg_init_opal_common();
	add_preferred_console("hvc", index, NULL);
	hvc_instantiate(index, index, ops);
out:
	of_node_put(stdout_node);
}

#ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_RAW
void __init udbg_init_debug_opal(void)
{
	u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
	hvc_opal_privs[index] = &hvc_opal_boot_priv;
	hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
	hvc_opal_boot_termno = index;
	udbg_init_opal_common();
}
#endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_RAW */

#ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI
void __init udbg_init_debug_opal_hvsi(void)
{
	u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
	hvc_opal_privs[index] = &hvc_opal_boot_priv;
	hvc_opal_boot_termno = index;
	udbg_init_opal_common();
	hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars, opal_put_chars,
		     index, 1);
	hvsilib_establish(&hvc_opal_boot_priv.hvsi);
}
#endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI */
Commit	Line	Data
daea1175 BH	1	/*
	2	* opal driver interface to hvc_console.c
	3	*
	4	* Copyright 2011 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	*
	20	*/
	21
	22	#undef DEBUG
	23
	24	#include <linux/types.h>
	25	#include <linux/init.h>
	26	#include <linux/delay.h>
	27	#include <linux/slab.h>
	28	#include <linux/console.h>
	29	#include <linux/of.h>
	30	#include <linux/of_platform.h>
0084e475	31	#include <linux/export.h>
daea1175 BH	32
	33	#include <asm/hvconsole.h>
	34	#include <asm/prom.h>
	35	#include <asm/firmware.h>
	36	#include <asm/hvsi.h>
	37	#include <asm/udbg.h>
	38	#include <asm/opal.h>
	39
	40	#include "hvc_console.h"
	41
	42	static const char hvc_opal_name[] = "hvc_opal";
	43
	44	static struct of_device_id hvc_opal_match[] __devinitdata = {
	45	{ .name = "serial", .compatible = "ibm,opal-console-raw" },
	46	{ .name = "serial", .compatible = "ibm,opal-console-hvsi" },
	47	{ },
	48	};
	49
	50	typedef enum hv_protocol {
	51	HV_PROTOCOL_RAW,
	52	HV_PROTOCOL_HVSI
	53	} hv_protocol_t;
	54
	55	struct hvc_opal_priv {
	56	hv_protocol_t proto; /* Raw data or HVSI packets */
	57	struct hvsi_priv hvsi; /* HVSI specific data */
	58	};
	59	static struct hvc_opal_priv *hvc_opal_privs[MAX_NR_HVC_CONSOLES];
	60
	61	/* For early boot console */
	62	static struct hvc_opal_priv hvc_opal_boot_priv;
	63	static u32 hvc_opal_boot_termno;
	64
	65	static const struct hv_ops hvc_opal_raw_ops = {
	66	.get_chars = opal_get_chars,
	67	.put_chars = opal_put_chars,
	68	.notifier_add = notifier_add_irq,
	69	.notifier_del = notifier_del_irq,
	70	.notifier_hangup = notifier_hangup_irq,
	71	};
	72
	73	static int hvc_opal_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
	74	{
	75	struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
	76
	77	if (WARN_ON(!pv))
	78	return -ENODEV;
	79
	80	return hvsilib_get_chars(&pv->hvsi, buf, count);
	81	}
	82
	83	static int hvc_opal_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
	84	{
	85	struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
	86
	87	if (WARN_ON(!pv))
	88	return -ENODEV;
	89
	90	return hvsilib_put_chars(&pv->hvsi, buf, count);
	91	}
	92
	93	static int hvc_opal_hvsi_open(struct hvc_struct *hp, int data)
	94	{
	95	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
96	int rc;
97
98	pr_devel("HVSI@%x: do open !\n", hp->vtermno);
99
100	rc = notifier_add_irq(hp, data);
101	if (rc)
102	return rc;
103
104	return hvsilib_open(&pv->hvsi, hp);
105	}
106
107	static void hvc_opal_hvsi_close(struct hvc_struct *hp, int data)
108	{
109	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
110
111	pr_devel("HVSI@%x: do close !\n", hp->vtermno);
112
113	hvsilib_close(&pv->hvsi, hp);
114
115	notifier_del_irq(hp, data);
116	}
117
118	void hvc_opal_hvsi_hangup(struct hvc_struct *hp, int data)
119	{
120	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
121
122	pr_devel("HVSI@%x: do hangup !\n", hp->vtermno);
123
124	hvsilib_close(&pv->hvsi, hp);
125
126	notifier_hangup_irq(hp, data);
127	}
128
129	static int hvc_opal_hvsi_tiocmget(struct hvc_struct *hp)
130	{
131	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
132
133	if (!pv)
134	return -EINVAL;
135	return pv->hvsi.mctrl;
136	}
137
138	static int hvc_opal_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set,
139	unsigned int clear)
140	{
141	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
142
143	pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n",
144	hp->vtermno, set, clear);
145
146	if (set & TIOCM_DTR)
147	hvsilib_write_mctrl(&pv->hvsi, 1);
148	else if (clear & TIOCM_DTR)
149	hvsilib_write_mctrl(&pv->hvsi, 0);
150
151	return 0;
152	}
153
154	static const struct hv_ops hvc_opal_hvsi_ops = {
155	.get_chars = hvc_opal_hvsi_get_chars,
156	.put_chars = hvc_opal_hvsi_put_chars,
157	.notifier_add = hvc_opal_hvsi_open,
158	.notifier_del = hvc_opal_hvsi_close,
159	.notifier_hangup = hvc_opal_hvsi_hangup,
160	.tiocmget = hvc_opal_hvsi_tiocmget,
161	.tiocmset = hvc_opal_hvsi_tiocmset,
162	};
163
164	static int __devinit hvc_opal_probe(struct platform_device *dev)
165	{
166	const struct hv_ops *ops;
167	struct hvc_struct *hp;
168	struct hvc_opal_priv *pv;
169	hv_protocol_t proto;
170	unsigned int termno, boot = 0;
171	const __be32 *reg;
172
173	if (of_device_is_compatible(dev->dev.of_node, "ibm,opal-console-raw")) {
174	proto = HV_PROTOCOL_RAW;
175	ops = &hvc_opal_raw_ops;
176	} else if (of_device_is_compatible(dev->dev.of_node,
177	"ibm,opal-console-hvsi")) {
178	proto = HV_PROTOCOL_HVSI;
179	ops = &hvc_opal_hvsi_ops;
180	} else {
181	pr_err("hvc_opal: Unkown protocol for %s\n",
182	dev->dev.of_node->full_name);
183	return -ENXIO;
184	}
185
186	reg = of_get_property(dev->dev.of_node, "reg", NULL);
187	termno = reg ? be32_to_cpup(reg) : 0;
188
189	/* Is it our boot one ? */
190	if (hvc_opal_privs[termno] == &hvc_opal_boot_priv) {
191	pv = hvc_opal_privs[termno];
192	boot = 1;
193	} else if (hvc_opal_privs[termno] == NULL) {
194	pv = kzalloc(sizeof(struct hvc_opal_priv), GFP_KERNEL);
195	if (!pv)
196	return -ENOMEM;
197	pv->proto = proto;
198	hvc_opal_privs[termno] = pv;
199	if (proto == HV_PROTOCOL_HVSI)
200	hvsilib_init(&pv->hvsi, opal_get_chars, opal_put_chars,
201	termno, 0);
202
203	/* Instanciate now to establish a mapping index==vtermno */
204	hvc_instantiate(termno, termno, ops);
205	} else {
206	pr_err("hvc_opal: Device %s has duplicate terminal number #%d\n",
207	dev->dev.of_node->full_name, termno);
208	return -ENXIO;
209	}
210
211	pr_info("hvc%d: %s protocol on %s%s\n", termno,
212	proto == HV_PROTOCOL_RAW ? "raw" : "hvsi",
213	dev->dev.of_node->full_name,
214	boot ? " (boot console)" : "");
215
216	/* We don't do IRQ yet */
217	hp = hvc_alloc(termno, 0, ops, MAX_VIO_PUT_CHARS);
218	if (IS_ERR(hp))
219	return PTR_ERR(hp);
220	dev_set_drvdata(&dev->dev, hp);
221
222	return 0;
223	}
224
225	static int __devexit hvc_opal_remove(struct platform_device *dev)
226	{
227	struct hvc_struct *hp = dev_get_drvdata(&dev->dev);
228	int rc, termno;
229
230	termno = hp->vtermno;
231	rc = hvc_remove(hp);
232	if (rc == 0) {
233	if (hvc_opal_privs[termno] != &hvc_opal_boot_priv)
234	kfree(hvc_opal_privs[termno]);
235	hvc_opal_privs[termno] = NULL;
236	}
237	return rc;
238	}
239
240	static struct platform_driver hvc_opal_driver = {
241	.probe = hvc_opal_probe,
242	.remove = __devexit_p(hvc_opal_remove),
243	.driver = {
244	.name = hvc_opal_name,
245	.owner = THIS_MODULE,
246	.of_match_table = hvc_opal_match,
247	}
248	};
249
250	static int __init hvc_opal_init(void)
251	{
252	if (!firmware_has_feature(FW_FEATURE_OPAL))
253	return -ENODEV;
254
255	/* Register as a vio device to receive callbacks */
256	return platform_driver_register(&hvc_opal_driver);
257	}
258	module_init(hvc_opal_init);
259
260	static void __exit hvc_opal_exit(void)
261	{
262	platform_driver_unregister(&hvc_opal_driver);
263	}
264	module_exit(hvc_opal_exit);
265
266	static void udbg_opal_putc(char c)
267	{
268	unsigned int termno = hvc_opal_boot_termno;
269	int count = -1;
270
271	if (c == '\n')
272	udbg_opal_putc('\r');
273
274	do {
275	switch(hvc_opal_boot_priv.proto) {
276	case HV_PROTOCOL_RAW:
277	count = opal_put_chars(termno, &c, 1);
278	break;
279	case HV_PROTOCOL_HVSI:
280	count = hvc_opal_hvsi_put_chars(termno, &c, 1);
281	break;
282	}
283	} while(count == 0 \|\| count == -EAGAIN);
284	}
285
286	static int udbg_opal_getc_poll(void)
287	{
288	unsigned int termno = hvc_opal_boot_termno;
289	int rc = 0;
290	char c;
291
292	switch(hvc_opal_boot_priv.proto) {
293	case HV_PROTOCOL_RAW:
294	rc = opal_get_chars(termno, &c, 1);
295	break;
296	case HV_PROTOCOL_HVSI:
297	rc = hvc_opal_hvsi_get_chars(termno, &c, 1);
298	break;
299	}
300	if (!rc)
301	return -1;
302	return c;
303	}
304
305	static int udbg_opal_getc(void)
306	{
307	int ch;
308	for (;;) {
309	ch = udbg_opal_getc_poll();
310	if (ch == -1) {
311	/* This shouldn't be needed...but... */
312	volatile unsigned long delay;
313	for (delay=0; delay < 2000000; delay++)
314	;
315	} else {
316	return ch;
317	}
318	}
319	}
320
321	static void udbg_init_opal_common(void)
322	{
323	udbg_putc = udbg_opal_putc;
324	udbg_getc = udbg_opal_getc;
325	udbg_getc_poll = udbg_opal_getc_poll;
326	tb_ticks_per_usec = 0x200; /* Make udelay not suck */
327	}
328
329	void __init hvc_opal_init_early(void)
330	{
331	struct device_node *stdout_node = NULL;
332	const u32 *termno;
333	const char *name = NULL;
334	const struct hv_ops *ops;
335	u32 index;
336
337	/* find the boot console from /chosen/stdout */
338	if (of_chosen)
339	name = of_get_property(of_chosen, "linux,stdout-path", NULL);
340	if (name) {
341	stdout_node = of_find_node_by_path(name);
342	if (!stdout_node) {
343	pr_err("hvc_opal: Failed to locate default console!\n");
344	return;
345	}
346	} else {
347	struct device_node opal, np;
348
349	/* Current OPAL takeover doesn't provide the stdout
350	* path, so we hard wire it
351	*/
352	opal = of_find_node_by_path("/ibm,opal/consoles");
353	if (opal)
354	pr_devel("hvc_opal: Found consoles in new location\n");
355	if (!opal) {
356	opal = of_find_node_by_path("/ibm,opal");
357	if (opal)
358	pr_devel("hvc_opal: "
359	"Found consoles in old location\n");
360	}
361	if (!opal)
362	return;
363	for_each_child_of_node(opal, np) {
364	if (!strcmp(np->name, "serial")) {
365	stdout_node = np;
366	break;
367	}
368	}
369	of_node_put(opal);
370	}
371	if (!stdout_node)
372	return;
373	termno = of_get_property(stdout_node, "reg", NULL);
374	index = termno ? *termno : 0;
375	if (index >= MAX_NR_HVC_CONSOLES)
376	return;
377	hvc_opal_privs[index] = &hvc_opal_boot_priv;
378
379	/* Check the protocol */
380	if (of_device_is_compatible(stdout_node, "ibm,opal-console-raw")) {
381	hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
382	ops = &hvc_opal_raw_ops;
383	pr_devel("hvc_opal: Found RAW console\n");
384	}
385	else if (of_device_is_compatible(stdout_node,"ibm,opal-console-hvsi")) {
386	hvc_opal_boot_priv.proto = HV_PROTOCOL_HVSI;
387	ops = &hvc_opal_hvsi_ops;
388	hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars,
389	opal_put_chars, index, 1);
390	/* HVSI, perform the handshake now */
391	hvsilib_establish(&hvc_opal_boot_priv.hvsi);
392	pr_devel("hvc_opal: Found HVSI console\n");
393	} else
394	goto out;
395	hvc_opal_boot_termno = index;
396	udbg_init_opal_common();
397	add_preferred_console("hvc", index, NULL);
398	hvc_instantiate(index, index, ops);
399	out:
400	of_node_put(stdout_node);
401	}
402
403	#ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_RAW
404	void __init udbg_init_debug_opal(void)
405	{
406	u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
407	hvc_opal_privs[index] = &hvc_opal_boot_priv;
408	hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
409	hvc_opal_boot_termno = index;
410	udbg_init_opal_common();
411	}
412	#endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_RAW */
413
414	#ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI
415	void __init udbg_init_debug_opal_hvsi(void)
416	{
417	u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
418	hvc_opal_privs[index] = &hvc_opal_boot_priv;
419	hvc_opal_boot_termno = index;
420	udbg_init_opal_common();
421	hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars, opal_put_chars,
422	index, 1);
423	hvsilib_establish(&hvc_opal_boot_priv.hvsi);
424	}
425	#endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI */