android_kernel_xiaomi_sm8350/arch/ppc64/kernel/hvconsole.c

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/*
* hvconsole.c
* Copyright (C) 2004 Hollis Blanchard, IBM Corporation
* Copyright (C) 2004 IBM Corporation
*
* Additional Author(s):
* Ryan S. Arnold <rsa@us.ibm.com>
*
* LPAR console support.
*
* 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 <linux/kernel.h>
#include <linux/module.h>
#include <asm/hvcall.h>
#include <asm/hvconsole.h>
#include <asm/prom.h>
/**
* hvc_get_chars - retrieve characters from firmware for denoted vterm adatper
* @vtermno: The vtermno or unit_address of the adapter from which to fetch the
* data.
* @buf: The character buffer into which to put the character data fetched from
* firmware.
* @count: not used?
*/
int hvc_get_chars(uint32_t vtermno, char *buf, int count)
{
unsigned long got;
if (plpar_hcall(H_GET_TERM_CHAR, vtermno, 0, 0, 0, &got,
(unsigned long *)buf, (unsigned long *)buf+1) == H_Success) {
/*
* Work around a HV bug where it gives us a null
* after every \r. -- paulus
*/
if (got > 0) {
int i;
for (i = 1; i < got; ++i) {
if (buf[i] == 0 && buf[i-1] == '\r') {
--got;
if (i < got)
memmove(&buf[i], &buf[i+1],
got - i);
}
}
}
return got;
}
return 0;
}
EXPORT_SYMBOL(hvc_get_chars);
/**
* hvc_put_chars: send characters to firmware for denoted vterm adapter
* @vtermno: The vtermno or unit_address of the adapter from which the data
* originated.
* @buf: The character buffer that contains the character data to send to
* firmware.
* @count: Send this number of characters.
*/
int hvc_put_chars(uint32_t vtermno, const char *buf, int count)
{
unsigned long *lbuf = (unsigned long *) buf;
long ret;
ret = plpar_hcall_norets(H_PUT_TERM_CHAR, vtermno, count, lbuf[0],
lbuf[1]);
if (ret == H_Success)
return count;
if (ret == H_Busy)
return 0;
return -EIO;
}
EXPORT_SYMBOL(hvc_put_chars);
/*
* We hope/assume that the first vty found corresponds to the first console
* device.
*/
int hvc_find_vtys(void)
{
struct device_node *vty;
int num_found = 0;
for (vty = of_find_node_by_name(NULL, "vty"); vty != NULL;
vty = of_find_node_by_name(vty, "vty")) {
uint32_t *vtermno;
/* We have statically defined space for only a certain number of
* console adapters. */
if (num_found >= MAX_NR_HVC_CONSOLES)
break;
vtermno = (uint32_t *)get_property(vty, "reg", NULL);
if (!vtermno)
continue;
if (device_is_compatible(vty, "hvterm1")) {
hvc_instantiate(*vtermno, num_found);
++num_found;
}
}
return num_found;
}