diff options
| -rw-r--r-- | arch/arc/Kconfig | 29 | ||||
| -rw-r--r-- | arch/arc/include/asm/arcregs.h | 12 | ||||
| -rw-r--r-- | arch/arc/include/asm/dsp-impl.h | 54 | ||||
| -rw-r--r-- | arch/arc/include/asm/entry-arcv2.h | 3 | ||||
| -rw-r--r-- | arch/arc/kernel/head.S | 4 | ||||
| -rw-r--r-- | arch/arc/kernel/setup.c | 3 |
6 files changed, 104 insertions, 1 deletions
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index 7124ab82dfa3..55432a8fc20d 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -401,13 +401,40 @@ config ARC_HAS_DIV_REM default y config ARC_HAS_ACCL_REGS - bool "Reg Pair ACCL:ACCH (FPU and/or MPY > 6)" + bool "Reg Pair ACCL:ACCH (FPU and/or MPY > 6 and/or DSP)" default y help Depending on the configuration, CPU can contain accumulator reg-pair (also referred to as r58:r59). These can also be used by gcc as GPR so kernel needs to save/restore per process +config ARC_DSP_HANDLED + def_bool n + +choice + prompt "DSP support" + default ARC_DSP_NONE + help + Depending on the configuration, CPU can contain DSP registers + (ACC0_GLO, ACC0_GHI, DSP_BFLY0, DSP_CTRL, DSP_FFT_CTRL). + Bellow is options describing how to handle these registers in + interrupt entry / exit and in context switch. + +config ARC_DSP_NONE + bool "No DSP extension presence in HW" + help + No DSP extension presence in HW + +config ARC_DSP_KERNEL + bool "DSP extension in HW, no support for userspace" + select ARC_HAS_ACCL_REGS + select ARC_DSP_HANDLED + help + 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 +endchoice + config ARC_IRQ_NO_AUTOSAVE bool "Disable hardware autosave regfile on interrupts" default n diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h index f7e432448e4b..135f6ec08a69 100644 --- a/arch/arc/include/asm/arcregs.h +++ b/arch/arc/include/asm/arcregs.h @@ -118,6 +118,18 @@ #define ARC_AUX_DPFP_2H 0x304 #define ARC_AUX_DPFP_STAT 0x305 +/* + * DSP-related registers + */ +#define ARC_AUX_DSP_BUILD 0x7A +#define ARC_AUX_ACC0_LO 0x580 +#define ARC_AUX_ACC0_GLO 0x581 +#define ARC_AUX_ACC0_HI 0x582 +#define ARC_AUX_ACC0_GHI 0x583 +#define ARC_AUX_DSP_BFLY0 0x598 +#define ARC_AUX_DSP_CTRL 0x59F +#define ARC_AUX_DSP_FFT_CTRL 0x59E + #ifndef __ASSEMBLY__ #include <soc/arc/aux.h> diff --git a/arch/arc/include/asm/dsp-impl.h b/arch/arc/include/asm/dsp-impl.h new file mode 100644 index 000000000000..606620383eca --- /dev/null +++ b/arch/arc/include/asm/dsp-impl.h @@ -0,0 +1,54 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2020 Synopsys, Inc. (www.synopsys.com) + * + * Author: Eugeniy Paltsev <[email protected]> + */ +#ifndef __ASM_ARC_DSP_IMPL_H +#define __ASM_ARC_DSP_IMPL_H + +#define DSP_CTRL_DISABLED_ALL 0 + +#ifdef __ASSEMBLY__ + +/* clobbers r5 register */ +.macro DSP_EARLY_INIT + lr r5, [ARC_AUX_DSP_BUILD] + bmsk r5, r5, 7 + breq r5, 0, 1f + mov r5, DSP_CTRL_DISABLED_ALL + sr r5, [ARC_AUX_DSP_CTRL] +1: +.endm + +/* clobbers r10, r11 registers pair */ +.macro DSP_SAVE_REGFILE_IRQ +#if defined(CONFIG_ARC_DSP_KERNEL) + /* + * Drop any changes to DSP_CTRL made by userspace so userspace won't be + * able to break kernel - reset it to DSP_CTRL_DISABLED_ALL value + */ + mov r10, DSP_CTRL_DISABLED_ALL + sr r10, [ARC_AUX_DSP_CTRL] +#endif /* ARC_DSP_KERNEL */ +.endm + +#else /* __ASEMBLY__ */ + +#include <asm/asserts.h> + +static inline bool dsp_exist(void) +{ + struct bcr_generic bcr; + + READ_BCR(ARC_AUX_DSP_BUILD, bcr); + return !!bcr.ver; +} + +static inline void dsp_config_check(void) +{ + CHK_OPT_STRICT(CONFIG_ARC_DSP_HANDLED, dsp_exist()); +} + +#endif /* __ASEMBLY__ */ +#endif /* __ASM_ARC_DSP_IMPL_H */ diff --git a/arch/arc/include/asm/entry-arcv2.h b/arch/arc/include/asm/entry-arcv2.h index 0b8b63d0bec1..dd6aa18b51ca 100644 --- a/arch/arc/include/asm/entry-arcv2.h +++ b/arch/arc/include/asm/entry-arcv2.h @@ -4,6 +4,7 @@ #define __ASM_ARC_ENTRY_ARCV2_H #include <asm/asm-offsets.h> +#include <asm/dsp-impl.h> #include <asm/irqflags-arcv2.h> #include <asm/thread_info.h> /* For THREAD_SIZE */ @@ -165,6 +166,8 @@ ST2 r58, r59, PT_r58 #endif + /* clobbers r10, r11 registers pair */ + DSP_SAVE_REGFILE_IRQ .endm /*------------------------------------------------------------------------*/ diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S index 6f41265f6250..6eb23f1545ee 100644 --- a/arch/arc/kernel/head.S +++ b/arch/arc/kernel/head.S @@ -14,6 +14,7 @@ #include <asm/entry.h> #include <asm/arcregs.h> #include <asm/cache.h> +#include <asm/dsp-impl.h> #include <asm/irqflags.h> .macro CPU_EARLY_SETUP @@ -59,6 +60,9 @@ #endif kflag r5 #endif + ; Config DSP_CTRL properly, so kernel may use integer multiply, + ; multiply-accumulate, and divide operations + DSP_EARLY_INIT .endm .section .init.text, "ax",@progbits diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c index 820c0cfb0702..1ed1528d9045 100644 --- a/arch/arc/kernel/setup.c +++ b/arch/arc/kernel/setup.c @@ -27,6 +27,7 @@ #include <asm/unwind.h> #include <asm/mach_desc.h> #include <asm/smp.h> +#include <asm/dsp-impl.h> #define FIX_PTR(x) __asm__ __volatile__(";" : "+r"(x)) @@ -440,6 +441,8 @@ static void arc_chk_core_config(void) /* Accumulator Low:High pair (r58:59) present if DSP MPY or FPU */ present = cpu->extn_mpy.dsp | cpu->extn.fpu_sp | cpu->extn.fpu_dp; CHK_OPT_STRICT(CONFIG_ARC_HAS_ACCL_REGS, present); + + dsp_config_check(); } } |