mips-mt.c
// SPDX-License-Identifier: GPL-2.0
/*
* General MIPS MT support routines, usable in AP/SP and SMVP.
* Copyright (C) 2005 Mips Technologies, Inc
*/
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/export.h>
#include <linux/interrupt.h>
#include <linux/security.h>
#include <asm/cpu.h>
#include <asm/processor.h>
#include <linux/atomic.h>
#include <asm/hardirq.h>
#include <asm/mmu_context.h>
#include <asm/mipsmtregs.h>
#include <asm/r4kcache.h>
#include <asm/cacheflush.h>
int vpelimit;
static int __init maxvpes(char *str)
{
get_option(&str, &vpelimit);
return 1;
}
__setup("maxvpes=", maxvpes);
int tclimit;
static int __init maxtcs(char *str)
{
get_option(&str, &tclimit);
return 1;
}
__setup("maxtcs=", maxtcs);
/*
* Dump new MIPS MT state for the core. Does not leave TCs halted.
* Takes an argument which taken to be a pre-call MVPControl value.
*/
void mips_mt_regdump(unsigned long mvpctl)
{
unsigned long flags;
unsigned long vpflags;
unsigned long mvpconf0;
int nvpe;
int ntc;
int i;
int tc;
unsigned long haltval;
unsigned long tcstatval;
local_irq_save(flags);
vpflags = dvpe();
printk("=== MIPS MT State Dump ===\n");
printk("-- Global State --\n");
printk(" MVPControl Passed: %08lx\n", mvpctl);
printk(" MVPControl Read: %08lx\n", vpflags);
printk(" MVPConf0 : %08lx\n", (mvpconf0 = read_c0_mvpconf0()));
nvpe = ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
ntc = ((mvpconf0 & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT) + 1;
printk("-- per-VPE State --\n");
for (i = 0; i < nvpe; i++) {
for (tc = 0; tc < ntc; tc++) {
settc(tc);
if ((read_tc_c0_tcbind() & TCBIND_CURVPE) == i) {
printk(" VPE %d\n", i);
printk(" VPEControl : %08lx\n",
read_vpe_c0_vpecontrol());
printk(" VPEConf0 : %08lx\n",
read_vpe_c0_vpeconf0());
printk(" VPE%d.Status : %08lx\n",
i, read_vpe_c0_status());
printk(" VPE%d.EPC : %08lx %pS\n",
i, read_vpe_c0_epc(),
(void *) read_vpe_c0_epc());
printk(" VPE%d.Cause : %08lx\n",
i, read_vpe_c0_cause());
printk(" VPE%d.Config7 : %08lx\n",
i, read_vpe_c0_config7());
break; /* Next VPE */
}
}
}
printk("-- per-TC State --\n");
for (tc = 0; tc < ntc; tc++) {
settc(tc);
if (read_tc_c0_tcbind() == read_c0_tcbind()) {
/* Are we dumping ourself? */
haltval = 0; /* Then we're not halted, and mustn't be */
tcstatval = flags; /* And pre-dump TCStatus is flags */
printk(" TC %d (current TC with VPE EPC above)\n", tc);
} else {
haltval = read_tc_c0_tchalt();
write_tc_c0_tchalt(1);
tcstatval = read_tc_c0_tcstatus();
printk(" TC %d\n", tc);
}
printk(" TCStatus : %08lx\n", tcstatval);
printk(" TCBind : %08lx\n", read_tc_c0_tcbind());
printk(" TCRestart : %08lx %pS\n",
read_tc_c0_tcrestart(), (void *) read_tc_c0_tcrestart());
printk(" TCHalt : %08lx\n", haltval);
printk(" TCContext : %08lx\n", read_tc_c0_tccontext());
if (!haltval)
write_tc_c0_tchalt(0);
}
printk("===========================\n");
evpe(vpflags);
local_irq_restore(flags);
}
static int mt_opt_rpsctl = -1;
static int mt_opt_nblsu = -1;
static int mt_opt_forceconfig7;
static int mt_opt_config7 = -1;
static int __init rpsctl_set(char *str)
{
get_option(&str, &mt_opt_rpsctl);
return 1;
}
__setup("rpsctl=", rpsctl_set);
static int __init nblsu_set(char *str)
{
get_option(&str, &mt_opt_nblsu);
return 1;
}
__setup("nblsu=", nblsu_set);
static int __init config7_set(char *str)
{
get_option(&str, &mt_opt_config7);
mt_opt_forceconfig7 = 1;
return 1;
}
__setup("config7=", config7_set);
static unsigned int itc_base;
static int __init set_itc_base(char *str)
{
get_option(&str, &itc_base);
return 1;
}
__setup("itcbase=", set_itc_base);
void mips_mt_set_cpuoptions(void)
{
unsigned int oconfig7 = read_c0_config7();
unsigned int nconfig7 = oconfig7;
if (mt_opt_rpsctl >= 0) {
printk("34K return prediction stack override set to %d.\n",
mt_opt_rpsctl);
if (mt_opt_rpsctl)
nconfig7 |= (1 << 2);
else
nconfig7 &= ~(1 << 2);
}
if (mt_opt_nblsu >= 0) {
printk("34K ALU/LSU sync override set to %d.\n", mt_opt_nblsu);
if (mt_opt_nblsu)
nconfig7 |= (1 << 5);
else
nconfig7 &= ~(1 << 5);
}
if (mt_opt_forceconfig7) {
printk("CP0.Config7 forced to 0x%08x.\n", mt_opt_config7);
nconfig7 = mt_opt_config7;
}
if (oconfig7 != nconfig7) {
__asm__ __volatile("sync");
write_c0_config7(nconfig7);
ehb();
printk("Config7: 0x%08x\n", read_c0_config7());
}
if (itc_base != 0) {
/*
* Configure ITC mapping. This code is very
* specific to the 34K core family, which uses
* a special mode bit ("ITC") in the ErrCtl
* register to enable access to ITC control
* registers via cache "tag" operations.
*/
unsigned long ectlval;
unsigned long itcblkgrn;
/* ErrCtl register is known as "ecc" to Linux */
ectlval = read_c0_ecc();
write_c0_ecc(ectlval | (0x1 << 26));
ehb();
#define INDEX_0 (0x80000000)
#define INDEX_8 (0x80000008)
/* Read "cache tag" for Dcache pseudo-index 8 */
cache_op(Index_Load_Tag_D, INDEX_8);
ehb();
itcblkgrn = read_c0_dtaglo();
itcblkgrn &= 0xfffe0000;
/* Set for 128 byte pitch of ITC cells */
itcblkgrn |= 0x00000c00;
/* Stage in Tag register */
write_c0_dtaglo(itcblkgrn);
ehb();
/* Write out to ITU with CACHE op */
cache_op(Index_Store_Tag_D, INDEX_8);
/* Now set base address, and turn ITC on with 0x1 bit */
write_c0_dtaglo((itc_base & 0xfffffc00) | 0x1 );
ehb();
/* Write out to ITU with CACHE op */
cache_op(Index_Store_Tag_D, INDEX_0);
write_c0_ecc(ectlval);
ehb();
printk("Mapped %ld ITC cells starting at 0x%08x\n",
((itcblkgrn & 0x7fe00000) >> 20), itc_base);
}
}
struct class *mt_class;
static int __init mt_init(void)
{
struct class *mtc;
mtc = class_create(THIS_MODULE, "mt");
if (IS_ERR(mtc))
return PTR_ERR(mtc);
mt_class = mtc;
return 0;
}
subsys_initcall(mt_init);