Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-12-25 12:21:37 +00:00
Code Issues Packages Projects Releases Wiki Activity

ARC: add support for DSP-enabled userspace applications

Browse Source 
To be able to run DSP-enabled userspace applications we need to
save and restore following DSP-related registers:
At IRQ/exception entry/exit:
 * DSP_CTRL (save it and reset to value suitable for kernel)
 * ACC0_LO, ACC0_HI (we already save them as r58, r59 pair)
At context switch:
 * ACC0_GLO, ACC0_GHI
 * DSP_BFLY0, DSP_FFT_CTRL

Reviewed-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This commit is contained in:
Eugeniy Paltsev 2020-03-05 23:02:51 +03:00 committed by Vineet Gupta
parent 4827d0cf74
commit 7321e2ea0d
9 changed files with 127 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
arch/arc/Kconfig
View File

@ -411,6 +411,9 @@ config ARC_HAS_ACCL_REGS
config ARC_DSP_HANDLED
def_bool n
config ARC_DSP_SAVE_RESTORE_REGS
def_bool n
choice
prompt "DSP support"
default ARC_DSP_NONE
@ -433,6 +436,15 @@ config ARC_DSP_KERNEL
DSP extension presence in HW, no support for DSP-enabled userspace
applications. We don't save / restore DSP registers and only do
some minimal preparations so userspace won't be able to break kernel
config ARC_DSP_USERSPACE
bool "Support DSP for userspace apps"
select ARC_HAS_ACCL_REGS
select ARC_DSP_HANDLED
select ARC_DSP_SAVE_RESTORE_REGS
help
DSP extension presence in HW, support save / restore DSP registers to
run DSP-enabled userspace applications
endchoice
config ARC_IRQ_NO_AUTOSAVE

2
arch/arc/include/asm/arcregs.h
View File

@ -120,6 +120,8 @@
/*
* DSP-related registers
* Registers names must correspond to dsp_callee_regs structure fields names
* for automatic offset calculation in DSP_AUX_SAVE_RESTORE macros.
*/
#define ARC_AUX_DSP_BUILD 0x7A
#define ARC_AUX_ACC0_LO 0x580

74
arch/arc/include/asm/dsp-impl.h
View File

@ -7,6 +7,8 @@
#ifndef __ASM_ARC_DSP_IMPL_H
#define __ASM_ARC_DSP_IMPL_H
#include <asm/dsp.h>
#define DSP_CTRL_DISABLED_ALL 0
#ifdef __ASSEMBLY__
@ -30,12 +32,82 @@
*/
mov r10, DSP_CTRL_DISABLED_ALL
sr r10, [ARC_AUX_DSP_CTRL]
#endif /* ARC_DSP_KERNEL */
#elif defined(CONFIG_ARC_DSP_SAVE_RESTORE_REGS)
/*
* Save DSP_CTRL register and reset it to value suitable for kernel
* (DSP_CTRL_DISABLED_ALL)
*/
mov r10, DSP_CTRL_DISABLED_ALL
aex r10, [ARC_AUX_DSP_CTRL]
st r10, [sp, PT_DSP_CTRL]
#endif
.endm
/* clobbers r10, r11 registers pair */
.macro DSP_RESTORE_REGFILE_IRQ
#if defined(CONFIG_ARC_DSP_SAVE_RESTORE_REGS)
ld r10, [sp, PT_DSP_CTRL]
sr r10, [ARC_AUX_DSP_CTRL]
#endif
.endm
#else /* __ASEMBLY__ */
#include <linux/sched.h>
#include <asm/asserts.h>
#include <asm/switch_to.h>
#ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS
/*
* As we save new and restore old AUX register value in the same place we
* can optimize a bit and use AEX instruction (swap contents of an auxiliary
* register with a core register) instead of LR + SR pair.
*/
#define AUX_SAVE_RESTORE(_saveto, _readfrom, _offt, _aux) \
do { \
long unsigned int _scratch; \
\
__asm__ __volatile__( \
"ld %0, [%2, %4] \n" \
"aex %0, [%3] \n" \
"st %0, [%1, %4] \n" \
: \
"=&r" (_scratch) /* must be early clobber */ \
: \
"r" (_saveto), \
"r" (_readfrom), \
"Ir" (_aux), \
"Ir" (_offt) \
: \
"memory" \
); \
} while (0)
#define DSP_AUX_SAVE_RESTORE(_saveto, _readfrom, _aux) \
AUX_SAVE_RESTORE(_saveto, _readfrom, \
offsetof(struct dsp_callee_regs, _aux), \
ARC_AUX_##_aux)
static inline void dsp_save_restore(struct task_struct *prev,
struct task_struct *next)
{
long unsigned int *saveto = &prev->thread.dsp.ACC0_GLO;
long unsigned int *readfrom = &next->thread.dsp.ACC0_GLO;
DSP_AUX_SAVE_RESTORE(saveto, readfrom, ACC0_GLO);
DSP_AUX_SAVE_RESTORE(saveto, readfrom, ACC0_GHI);
DSP_AUX_SAVE_RESTORE(saveto, readfrom, DSP_BFLY0);
DSP_AUX_SAVE_RESTORE(saveto, readfrom, DSP_FFT_CTRL);
}
#else /* !CONFIG_ARC_DSP_SAVE_RESTORE_REGS */
#define dsp_save_restore(p, n)
#endif /* CONFIG_ARC_DSP_SAVE_RESTORE_REGS */
static inline bool dsp_exist(void)
{

24
arch/arc/include/asm/dsp.h Normal file
View File

@ -0,0 +1,24 @@
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2020 Synopsys, Inc. (www.synopsys.com)
*
* Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
*/
#ifndef __ASM_ARC_DSP_H
#define __ASM_ARC_DSP_H
#ifndef __ASSEMBLY__
/*
* DSP-related saved registers - need to be saved only when you are
* scheduled out.
* structure fields name must correspond to aux register defenitions for
* automatic offset calculation in DSP_AUX_SAVE_RESTORE macros
*/
struct dsp_callee_regs {
unsigned long ACC0_GLO, ACC0_GHI, DSP_BFLY0, DSP_FFT_CTRL;
};
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_ARC_DSP_H */

3
arch/arc/include/asm/entry-arcv2.h
View File

@ -192,6 +192,9 @@
ld r25, [sp, PT_user_r25]
#endif
/* clobbers r10, r11 registers pair */
DSP_RESTORE_REGFILE_IRQ
#ifdef CONFIG_ARC_HAS_ACCL_REGS
LD2 r58, r59, PT_r58
#endif

4
arch/arc/include/asm/processor.h
View File

@ -14,6 +14,7 @@
#ifndef __ASSEMBLY__
#include <asm/ptrace.h>
#include <asm/dsp.h>
#include <asm/fpu.h>
#ifdef CONFIG_ARC_PLAT_EZNPS
@ -31,6 +32,9 @@ struct thread_struct {
unsigned long ksp; /* kernel mode stack pointer */
unsigned long callee_reg; /* pointer to callee regs */
unsigned long fault_address; /* dbls as brkpt holder as well */
#ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS
struct dsp_callee_regs dsp;
#endif
#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
struct arc_fpu fpu;
#endif

3
arch/arc/include/asm/ptrace.h
View File

@ -91,6 +91,9 @@ struct pt_regs {
#ifdef CONFIG_ARC_HAS_ACCL_REGS
unsigned long r58, r59; /* ACCL/ACCH used by FPU / DSP MPY */
#endif
#ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS
unsigned long DSP_CTRL;
#endif
/*------- Below list auto saved by h/w -----------*/
unsigned long r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11;

2
arch/arc/include/asm/switch_to.h
View File

@ -9,6 +9,7 @@
#ifndef __ASSEMBLY__
#include <linux/sched.h>
#include <asm/dsp-impl.h>
#include <asm/fpu.h>
#ifdef CONFIG_ARC_PLAT_EZNPS
@ -24,6 +25,7 @@ struct task_struct *__switch_to(struct task_struct *p, struct task_struct *n);
#define switch_to(prev, next, last) \
do { \
ARC_EZNPS_DP_PREV(prev, next); \
dsp_save_restore(prev, next); \
fpu_save_restore(prev, next); \
last = __switch_to(prev, next);\
mb(); \

4
arch/arc/kernel/asm-offsets.c
View File

@ -12,6 +12,7 @@
#include <asm/hardirq.h>
#include <asm/page.h>
int main(void)
{
DEFINE(TASK_THREAD, offsetof(struct task_struct, thread));
@ -75,6 +76,9 @@ int main(void)
OFFSET(PT_r58, pt_regs, r58);
OFFSET(PT_r59, pt_regs, r59);
#endif
#ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS
OFFSET(PT_DSP_CTRL, pt_regs, DSP_CTRL);
#endif
return 0;
}