Staging
v0.7.0
v0.7.0
https://github.com/torvalds/linux
Tip revision: fc74e0a40e4f9fd0468e34045b0c45bba11dcbb2 authored by Linus Torvalds on 26 December 2021, 21:17:17 UTC
Linux 5.16-rc7
Linux 5.16-rc7
Tip revision: fc74e0a
wbflush.c
/*
* Setup the right wbflush routine for the different DECstations.
*
* Created with information from:
* DECstation 3100 Desktop Workstation Functional Specification
* DECstation 5000/200 KN02 System Module Functional Specification
* mipsel-linux-objdump --disassemble vmunix | grep "wbflush" :-)
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1998 Harald Koerfgen
* Copyright (C) 2002 Maciej W. Rozycki
*/
#include <linux/export.h>
#include <linux/init.h>
#include <asm/bootinfo.h>
#include <asm/wbflush.h>
#include <asm/barrier.h>
static void wbflush_kn01(void);
static void wbflush_kn210(void);
static void wbflush_mips(void);
void (*__wbflush) (void);
void __init wbflush_setup(void)
{
switch (mips_machtype) {
case MACH_DS23100:
case MACH_DS5000_200: /* DS5000 3max */
__wbflush = wbflush_kn01;
break;
case MACH_DS5100: /* DS5100 MIPSMATE */
__wbflush = wbflush_kn210;
break;
case MACH_DS5000_1XX: /* DS5000/100 3min */
case MACH_DS5000_XX: /* Personal DS5000/2x */
case MACH_DS5000_2X0: /* DS5000/240 3max+ */
case MACH_DS5900: /* DS5900 bigmax */
default:
__wbflush = wbflush_mips;
break;
}
}
/*
* For the DS3100 and DS5000/200 the R2020/R3220 writeback buffer functions
* as part of Coprocessor 0.
*/
static void wbflush_kn01(void)
{
asm(".set\tpush\n\t"
".set\tnoreorder\n\t"
"1:\tbc0f\t1b\n\t"
"nop\n\t"
".set\tpop");
}
/*
* For the DS5100 the writeback buffer seems to be a part of Coprocessor 3.
* But CP3 has to enabled first.
*/
static void wbflush_kn210(void)
{
asm(".set\tpush\n\t"
".set\tnoreorder\n\t"
"mfc0\t$2,$12\n\t"
"lui\t$3,0x8000\n\t"
"or\t$3,$2,$3\n\t"
"mtc0\t$3,$12\n\t"
"nop\n"
"1:\tbc3f\t1b\n\t"
"nop\n\t"
"mtc0\t$2,$12\n\t"
"nop\n\t"
".set\tpop"
: : : "$2", "$3");
}
/*
* I/O ASIC systems use a standard writeback buffer that gets flushed
* upon an uncached read.
*/
static void wbflush_mips(void)
{
__fast_iob();
}
EXPORT_SYMBOL(__wbflush);