MIPS: MT: Remove SMTC support

Nobody is maintaining SMTC anymore and there also seems to be no userbase.
Which is a pity - the SMTC technology primarily developed by Kevin D.
Kissell <kevink@paralogos.com> is an ingenious demonstration for the MT
ASE's power and elegance.

Based on Markos Chandras <Markos.Chandras@imgtec.com> patch
https://patchwork.linux-mips.org/patch/6719/ which while very similar did
no longer apply cleanly when I tried to merge it plus some additional
post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to
merge once upon a time.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Ralf Baechle
2014-05-23 16:29:44 +02:00
parent 8b2e62cc34
commit b633648c5a
64 changed files with 72 additions and 4097 deletions

View File

@@ -17,7 +17,7 @@
#include <linux/stringify.h>
#include <asm/hazards.h>
#if defined(CONFIG_CPU_MIPSR2) && !defined(CONFIG_MIPS_MT_SMTC)
#ifdef CONFIG_CPU_MIPSR2
static inline void arch_local_irq_disable(void)
{
@@ -118,30 +118,15 @@ void arch_local_irq_disable(void);
unsigned long arch_local_irq_save(void);
void arch_local_irq_restore(unsigned long flags);
void __arch_local_irq_restore(unsigned long flags);
#endif /* if defined(CONFIG_CPU_MIPSR2) && !defined(CONFIG_MIPS_MT_SMTC) */
extern void smtc_ipi_replay(void);
#endif /* CONFIG_CPU_MIPSR2 */
static inline void arch_local_irq_enable(void)
{
#ifdef CONFIG_MIPS_MT_SMTC
/*
* SMTC kernel needs to do a software replay of queued
* IPIs, at the cost of call overhead on each local_irq_enable()
*/
smtc_ipi_replay();
#endif
__asm__ __volatile__(
" .set push \n"
" .set reorder \n"
" .set noat \n"
#ifdef CONFIG_MIPS_MT_SMTC
" mfc0 $1, $2, 1 # SMTC - clear TCStatus.IXMT \n"
" ori $1, 0x400 \n"
" xori $1, 0x400 \n"
" mtc0 $1, $2, 1 \n"
#elif defined(CONFIG_CPU_MIPSR2)
#if defined(CONFIG_CPU_MIPSR2)
" ei \n"
#else
" mfc0 $1,$12 \n"
@@ -163,11 +148,7 @@ static inline unsigned long arch_local_save_flags(void)
asm __volatile__(
" .set push \n"
" .set reorder \n"
#ifdef CONFIG_MIPS_MT_SMTC
" mfc0 %[flags], $2, 1 \n"
#else
" mfc0 %[flags], $12 \n"
#endif
" .set pop \n"
: [flags] "=r" (flags));
@@ -177,14 +158,7 @@ static inline unsigned long arch_local_save_flags(void)
static inline int arch_irqs_disabled_flags(unsigned long flags)
{
#ifdef CONFIG_MIPS_MT_SMTC
/*
* SMTC model uses TCStatus.IXMT to disable interrupts for a thread/CPU
*/
return flags & 0x400;
#else
return !(flags & 1);
#endif
}
#endif /* #ifndef __ASSEMBLY__ */