tegrakernel/kernel/kernel-4.9/arch/powerpc/platforms/pseries/hvconsole.c

89 lines
2.5 KiB
C

/*
* 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/export.h>
#include <linux/errno.h>
#include <asm/hvcall.h>
#include <asm/hvconsole.h>
#include <asm/plpar_wrappers.h>
/**
* hvc_get_chars - retrieve characters from firmware for denoted vterm adapter
* @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)
{
long ret;
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
unsigned long *lbuf = (unsigned long *)buf;
ret = plpar_hcall(H_GET_TERM_CHAR, retbuf, vtermno);
lbuf[0] = be64_to_cpu(retbuf[1]);
lbuf[1] = be64_to_cpu(retbuf[2]);
if (ret == H_SUCCESS)
return retbuf[0];
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. Must be at least 16 bytes, even if count is less than 16.
* @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;
/* hcall will ret H_PARAMETER if 'count' exceeds firmware max.*/
if (count > MAX_VIO_PUT_CHARS)
count = MAX_VIO_PUT_CHARS;
ret = plpar_hcall_norets(H_PUT_TERM_CHAR, vtermno, count,
cpu_to_be64(lbuf[0]),
cpu_to_be64(lbuf[1]));
if (ret == H_SUCCESS)
return count;
if (ret == H_BUSY)
return -EAGAIN;
return -EIO;
}
EXPORT_SYMBOL(hvc_put_chars);