linux-stable/drivers/tty/hvc/hvc_opal.c
Rob Herring 778ec49c14 tty: Use of_node_name_{eq,prefix} for node name comparisons
Convert string compares of DT node names to use of_node_name_eq helper
instead. This removes direct access to the node name pointer.

For hvc, the code can also be simplified by using of_stdout pointer
instead of searching again for the stdout node.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-serial@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-17 16:12:17 +01:00

419 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* opal driver interface to hvc_console.c
*
* Copyright 2011 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
*/
#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 <linux/interrupt.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 const struct of_device_id hvc_opal_match[] = {
{ .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,
.flush = opal_flush_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,
.flush = opal_flush_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 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, irq, 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: Unknown protocol for %pOF\n",
dev->dev.of_node);
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) {
/*
* We want put_chars to be atomic to avoid mangling of
* hvsi packets.
*/
hvsilib_init(&pv->hvsi,
opal_get_chars, opal_put_chars_atomic,
termno, 0);
}
/* Instanciate now to establish a mapping index==vtermno */
hvc_instantiate(termno, termno, ops);
} else {
pr_err("hvc_opal: Device %pOF has duplicate terminal number #%d\n",
dev->dev.of_node, termno);
return -ENXIO;
}
pr_info("hvc%d: %s protocol on %pOF%s\n", termno,
proto == HV_PROTOCOL_RAW ? "raw" : "hvsi",
dev->dev.of_node,
boot ? " (boot console)" : "");
irq = irq_of_parse_and_map(dev->dev.of_node, 0);
if (!irq) {
pr_info("hvc%d: No interrupts property, using OPAL event\n",
termno);
irq = opal_event_request(ilog2(OPAL_EVENT_CONSOLE_INPUT));
}
if (!irq) {
pr_err("hvc_opal: Unable to map interrupt for device %pOF\n",
dev->dev.of_node);
return irq;
}
hp = hvc_alloc(termno, irq, ops, MAX_VIO_PUT_CHARS);
if (IS_ERR(hp))
return PTR_ERR(hp);
/* hvc consoles on powernv may need to share a single irq */
hp->flags = IRQF_SHARED;
dev_set_drvdata(&dev->dev, hp);
return 0;
}
static int 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 = hvc_opal_remove,
.driver = {
.name = hvc_opal_name,
.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);
}
device_initcall(hvc_opal_init);
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;
}
/* This is needed for the cosole to flush
* when there aren't any interrupts.
*/
opal_flush_console(termno);
} 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)
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;
}
void __init hvc_opal_init_early(void)
{
struct device_node *stdout_node = of_node_get(of_stdout);
const __be32 *termno;
const struct hv_ops *ops;
u32 index;
/* If the console wasn't in /chosen, try /ibm,opal */
if (!stdout_node) {
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 (of_node_name_eq(np, "serial")) {
stdout_node = np;
break;
}
}
of_node_put(opal);
}
if (!stdout_node)
return;
termno = of_get_property(stdout_node, "reg", NULL);
index = termno ? be32_to_cpup(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_atomic,
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_raw(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_atomic,
index, 1);
hvsilib_establish(&hvc_opal_boot_priv.hvsi);
}
#endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI */