diff options
Diffstat (limited to 'arch/arc')
48 files changed, 670 insertions, 876 deletions
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index 5917099470e..4a0e54fc01b 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -184,6 +184,7 @@ config ARC_CACHE_PAGES config ARC_CACHE_VIPT_ALIASING bool "Support VIPT Aliasing D$" + depends on ARC_HAS_DCACHE default n endif #ARC_CACHE @@ -361,13 +362,6 @@ config ARC_MISALIGN_ACCESS Use ONLY-IF-ABS-NECESSARY as it will be very slow and also can hide potential bugs in code -config ARC_STACK_NONEXEC - bool "Make stack non-executable" - default n - help - To disable the execute permissions of stack/heap of processes - which are enabled by default. - config HZ int "Timer Frequency" default 100 diff --git a/arch/arc/Makefile b/arch/arc/Makefile index 183397fd289..8c0b1aa56f7 100644 --- a/arch/arc/Makefile +++ b/arch/arc/Makefile @@ -9,25 +9,27 @@ UTS_MACHINE := arc ifeq ($(CROSS_COMPILE),) -CROSS_COMPILE := arc-elf32- +CROSS_COMPILE := arc-linux-uclibc- endif KBUILD_DEFCONFIG := fpga_defconfig cflags-y += -mA7 -fno-common -pipe -fno-builtin -D__linux__ -LINUXINCLUDE += -include ${src}/arch/arc/include/asm/defines.h - ifdef CONFIG_ARC_CURR_IN_REG # For a global register defintion, make sure it gets passed to every file # We had a customer reported bug where some code built in kernel was NOT using # any kernel headers, and missing the r25 global register -# Can't do unconditionally (like above) because of recursive include issues +# Can't do unconditionally because of recursive include issues # due to <linux/thread_info.h> LINUXINCLUDE += -include ${src}/arch/arc/include/asm/current.h endif -atleast_gcc44 := $(call cc-ifversion, -gt, 0402, y) +upto_gcc42 := $(call cc-ifversion, -le, 0402, y) +upto_gcc44 := $(call cc-ifversion, -le, 0404, y) +atleast_gcc44 := $(call cc-ifversion, -ge, 0404, y) +atleast_gcc48 := $(call cc-ifversion, -ge, 0408, y) + cflags-$(atleast_gcc44) += -fsection-anchors cflags-$(CONFIG_ARC_HAS_LLSC) += -mlock @@ -35,6 +37,11 @@ cflags-$(CONFIG_ARC_HAS_SWAPE) += -mswape cflags-$(CONFIG_ARC_HAS_RTSC) += -mrtsc cflags-$(CONFIG_ARC_DW2_UNWIND) += -fasynchronous-unwind-tables +# By default gcc 4.8 generates dwarf4 which kernel unwinder can't grok +ifeq ($(atleast_gcc48),y) +cflags-$(CONFIG_ARC_DW2_UNWIND) += -gdwarf-2 +endif + ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE # Generic build system uses -O2, we want -O3 cflags-y += -O3 @@ -48,11 +55,10 @@ cflags-$(disable_small_data) += -mno-sdata -fcall-used-gp cflags-$(CONFIG_CPU_BIG_ENDIAN) += -mbig-endian ldflags-$(CONFIG_CPU_BIG_ENDIAN) += -EB -# STAR 9000518362: +# STAR 9000518362: (fixed with binutils shipping with gcc 4.8) # arc-linux-uclibc-ld (buildroot) or arceb-elf32-ld (EZChip) don't accept -# --build-id w/o "-marclinux". -# Default arc-elf32-ld is OK -ldflags-y += -marclinux +# --build-id w/o "-marclinux". Default arc-elf32-ld is OK +ldflags-$(upto_gcc44) += -marclinux ARC_LIBGCC := -mA7 cflags-$(CONFIG_ARC_HAS_HW_MPY) += -multcost=16 @@ -66,8 +72,8 @@ ifndef CONFIG_ARC_HAS_HW_MPY # With gcc 4.4.7, -mno-mpy is enough to make any other related adjustments, # e.g. increased cost of MPY. With gcc 4.2.1 this had to be explicitly hinted - ARC_LIBGCC := -marc600 - ifneq ($(atleast_gcc44),y) + ifeq ($(upto_gcc42),y) + ARC_LIBGCC := -marc600 cflags-y += -multcost=30 endif endif diff --git a/arch/arc/configs/fpga_defconfig b/arch/arc/configs/fpga_defconfig index 95350be6ef6..c109af32027 100644 --- a/arch/arc/configs/fpga_defconfig +++ b/arch/arc/configs/fpga_defconfig @@ -1,4 +1,4 @@ -CONFIG_CROSS_COMPILE="arc-elf32-" +CONFIG_CROSS_COMPILE="arc-linux-uclibc-" # CONFIG_LOCALVERSION_AUTO is not set CONFIG_DEFAULT_HOSTNAME="ARCLinux" # CONFIG_SWAP is not set diff --git a/arch/arc/configs/nsimosci_defconfig b/arch/arc/configs/nsimosci_defconfig index 446c96c24ef..451af30914f 100644 --- a/arch/arc/configs/nsimosci_defconfig +++ b/arch/arc/configs/nsimosci_defconfig @@ -1,4 +1,4 @@ -CONFIG_CROSS_COMPILE="arc-elf32-" +CONFIG_CROSS_COMPILE="arc-linux-uclibc-" # CONFIG_LOCALVERSION_AUTO is not set CONFIG_DEFAULT_HOSTNAME="ARCLinux" # CONFIG_SWAP is not set diff --git a/arch/arc/configs/tb10x_defconfig b/arch/arc/configs/tb10x_defconfig index 4fa5cd9f220..6be6492442d 100644 --- a/arch/arc/configs/tb10x_defconfig +++ b/arch/arc/configs/tb10x_defconfig @@ -1,4 +1,4 @@ -CONFIG_CROSS_COMPILE="arc-elf32-" +CONFIG_CROSS_COMPILE="arc-linux-uclibc-" # CONFIG_LOCALVERSION_AUTO is not set CONFIG_DEFAULT_HOSTNAME="tb10x" CONFIG_SYSVIPC=y diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h index 1b907c46566..355cb470c2a 100644 --- a/arch/arc/include/asm/arcregs.h +++ b/arch/arc/include/asm/arcregs.h @@ -20,7 +20,6 @@ #define ARC_REG_PERIBASE_BCR 0x69 #define ARC_REG_FP_BCR 0x6B /* Single-Precision FPU */ #define ARC_REG_DPFP_BCR 0x6C /* Dbl Precision FPU */ -#define ARC_REG_MMU_BCR 0x6f #define ARC_REG_DCCM_BCR 0x74 /* DCCM Present + SZ */ #define ARC_REG_TIMERS_BCR 0x75 #define ARC_REG_ICCM_BCR 0x78 @@ -34,22 +33,12 @@ #define ARC_REG_D_UNCACH_BCR 0x6A /* status32 Bits Positions */ -#define STATUS_H_BIT 0 /* CPU Halted */ -#define STATUS_E1_BIT 1 /* Int 1 enable */ -#define STATUS_E2_BIT 2 /* Int 2 enable */ -#define STATUS_A1_BIT 3 /* Int 1 active */ -#define STATUS_A2_BIT 4 /* Int 2 active */ #define STATUS_AE_BIT 5 /* Exception active */ #define STATUS_DE_BIT 6 /* PC is in delay slot */ #define STATUS_U_BIT 7 /* User/Kernel mode */ #define STATUS_L_BIT 12 /* Loop inhibit */ /* These masks correspond to the status word(STATUS_32) bits */ -#define STATUS_H_MASK (1<<STATUS_H_BIT) -#define STATUS_E1_MASK (1<<STATUS_E1_BIT) -#define STATUS_E2_MASK (1<<STATUS_E2_BIT) -#define STATUS_A1_MASK (1<<STATUS_A1_BIT) -#define STATUS_A2_MASK (1<<STATUS_A2_BIT) #define STATUS_AE_MASK (1<<STATUS_AE_BIT) #define STATUS_DE_MASK (1<<STATUS_DE_BIT) #define STATUS_U_MASK (1<<STATUS_U_BIT) @@ -71,6 +60,7 @@ #define ECR_V_ITLB_MISS 0x21 #define ECR_V_DTLB_MISS 0x22 #define ECR_V_PROTV 0x23 +#define ECR_V_TRAP 0x25 /* Protection Violation Exception Cause Code Values */ #define ECR_C_PROTV_INST_FETCH 0x00 @@ -79,94 +69,23 @@ #define ECR_C_PROTV_XCHG 0x03 #define ECR_C_PROTV_MISALIG_DATA 0x04 +#define ECR_C_BIT_PROTV_MISALIG_DATA 10 + +/* Machine Check Cause Code Values */ +#define ECR_C_MCHK_DUP_TLB 0x01 + /* DTLB Miss Exception Cause Code Values */ #define ECR_C_BIT_DTLB_LD_MISS 8 #define ECR_C_BIT_DTLB_ST_MISS 9 +/* Dummy ECR values for Interrupts */ +#define event_IRQ1 0x0031abcd +#define event_IRQ2 0x0032abcd /* Auxiliary registers */ #define AUX_IDENTITY 4 #define AUX_INTR_VEC_BASE 0x25 -#define AUX_IRQ_LEV 0x200 /* IRQ Priority: L1 or L2 */ -#define AUX_IRQ_HINT 0x201 /* For generating Soft Interrupts */ -#define AUX_IRQ_LV12 0x43 /* interrupt level register */ - -#define AUX_IENABLE 0x40c -#define AUX_ITRIGGER 0x40d -#define AUX_IPULSE 0x415 - -/* Timer related Aux registers */ -#define ARC_REG_TIMER0_LIMIT 0x23 /* timer 0 limit */ -#define ARC_REG_TIMER0_CTRL 0x22 /* timer 0 control */ -#define ARC_REG_TIMER0_CNT 0x21 /* timer 0 count */ -#define ARC_REG_TIMER1_LIMIT 0x102 /* timer 1 limit */ -#define ARC_REG_TIMER1_CTRL 0x101 /* timer 1 control */ -#define ARC_REG_TIMER1_CNT 0x100 /* timer 1 count */ - -#define TIMER_CTRL_IE (1 << 0) /* Interupt when Count reachs limit */ -#define TIMER_CTRL_NH (1 << 1) /* Count only when CPU NOT halted */ - -/* MMU Management regs */ -#define ARC_REG_TLBPD0 0x405 -#define ARC_REG_TLBPD1 0x406 -#define ARC_REG_TLBINDEX 0x407 -#define ARC_REG_TLBCOMMAND 0x408 -#define ARC_REG_PID 0x409 -#define ARC_REG_SCRATCH_DATA0 0x418 - -/* Bits in MMU PID register */ -#define MMU_ENABLE (1 << 31) /* Enable MMU for process */ - -/* Error code if probe fails */ -#define TLB_LKUP_ERR 0x80000000 - -/* TLB Commands */ -#define TLBWrite 0x1 -#define TLBRead 0x2 -#define TLBGetIndex 0x3 -#define TLBProbe 0x4 - -#if (CONFIG_ARC_MMU_VER >= 2) -#define TLBWriteNI 0x5 /* write JTLB without inv uTLBs */ -#define TLBIVUTLB 0x6 /* explicitly inv uTLBs */ -#else -#undef TLBWriteNI /* These cmds don't exist on older MMU */ -#undef TLBIVUTLB -#endif -/* Instruction cache related Auxiliary registers */ -#define ARC_REG_IC_BCR 0x77 /* Build Config reg */ -#define ARC_REG_IC_IVIC 0x10 -#define ARC_REG_IC_CTRL 0x11 -#define ARC_REG_IC_IVIL 0x19 -#if (CONFIG_ARC_MMU_VER > 2) -#define ARC_REG_IC_PTAG 0x1E -#endif - -/* Bit val in IC_CTRL */ -#define IC_CTRL_CACHE_DISABLE 0x1 - -/* Data cache related Auxiliary registers */ -#define ARC_REG_DC_BCR 0x72 -#define ARC_REG_DC_IVDC 0x47 -#define ARC_REG_DC_CTRL 0x48 -#define ARC_REG_DC_IVDL 0x4A -#define ARC_REG_DC_FLSH 0x4B -#define ARC_REG_DC_FLDL 0x4C -#if (CONFIG_ARC_MMU_VER > 2) -#define ARC_REG_DC_PTAG 0x5C -#endif - -/* Bit val in DC_CTRL */ -#define DC_CTRL_INV_MODE_FLUSH 0x40 -#define DC_CTRL_FLUSH_STATUS 0x100 - -/* MMU Management regs */ -#define ARC_REG_PID 0x409 -#define ARC_REG_SCRATCH_DATA0 0x418 - -/* Bits in MMU PID register */ -#define MMU_ENABLE (1 << 31) /* Enable MMU for process */ /* * Floating Pt Registers @@ -293,24 +212,6 @@ struct bcr_identity { #endif }; -struct bcr_mmu_1_2 { -#ifdef CONFIG_CPU_BIG_ENDIAN - unsigned int ver:8, ways:4, sets:4, u_itlb:8, u_dtlb:8; -#else - unsigned int u_dtlb:8, u_itlb:8, sets:4, ways:4, ver:8; -#endif -}; - -struct bcr_mmu_3 { -#ifdef CONFIG_CPU_BIG_ENDIAN - unsigned int ver:8, ways:4, sets:4, osm:1, reserv:3, pg_sz:4, - u_itlb:4, u_dtlb:4; -#else - unsigned int u_dtlb:4, u_itlb:4, pg_sz:4, reserv:3, osm:1, sets:4, - ways:4, ver:8; -#endif -}; - #define EXTN_SWAP_VALID 0x1 #define EXTN_NORM_VALID 0x2 #define EXTN_MINMAX_VALID 0x2 @@ -343,14 +244,6 @@ struct bcr_extn_xymem { #endif }; -struct bcr_cache { -#ifdef CONFIG_CPU_BIG_ENDIAN - unsigned int pad:12, line_len:4, sz:4, config:4, ver:8; -#else - unsigned int ver:8, config:4, sz:4, line_len:4, pad:12; -#endif -}; - struct bcr_perip { #ifdef CONFIG_CPU_BIG_ENDIAN unsigned int start:8, pad2:8, sz:8, pad:8; @@ -403,7 +296,7 @@ struct cpuinfo_arc_mmu { }; struct cpuinfo_arc_cache { - unsigned int has_aliasing, sz, line_len, assoc, ver; + unsigned int sz, line_len, assoc, ver; }; struct cpuinfo_arc_ccm { diff --git a/arch/arc/include/asm/bug.h b/arch/arc/include/asm/bug.h index 2ad8f9b1c54..5b18e94c667 100644 --- a/arch/arc/include/asm/bug.h +++ b/arch/arc/include/asm/bug.h @@ -18,9 +18,8 @@ struct task_struct; void show_regs(struct pt_regs *regs); void show_stacktrace(struct task_struct *tsk, struct pt_regs *regs); void show_kernel_fault_diag(const char *str, struct pt_regs *regs, - unsigned long address, unsigned long cause_reg); -void die(const char *str, struct pt_regs *regs, unsigned long address, - unsigned long cause_reg); + unsigned long address); +void die(const char *str, struct pt_regs *regs, unsigned long address); #define BUG() do { \ dump_stack(); \ diff --git a/arch/arc/include/asm/cache.h b/arch/arc/include/asm/cache.h index d5555fe4742..5802849a6ca 100644 --- a/arch/arc/include/asm/cache.h +++ b/arch/arc/include/asm/cache.h @@ -18,21 +18,19 @@ #define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT) -#define ARC_ICACHE_WAYS 2 -#define ARC_DCACHE_WAYS 4 - -/* Helpers */ +/* For a rare case where customers have differently config I/D */ #define ARC_ICACHE_LINE_LEN L1_CACHE_BYTES #define ARC_DCACHE_LINE_LEN L1_CACHE_BYTES #define ICACHE_LINE_MASK (~(ARC_ICACHE_LINE_LEN - 1)) #define DCACHE_LINE_MASK (~(ARC_DCACHE_LINE_LEN - 1)) -#if ARC_ICACHE_LINE_LEN != ARC_DCACHE_LINE_LEN -#error "Need to fix some code as I/D cache lines not same" -#else -#define is_not_cache_aligned(p) ((unsigned long)p & (~DCACHE_LINE_MASK)) -#endif +/* + * ARC700 doesn't cache any access in top 256M. + * Ideal for wiring memory mapped peripherals as we don't need to do + * explicit uncached accesses (LD.di/ST.di) hence more portable drivers + */ +#define ARC_UNCACHED_ADDR_SPACE 0xc0000000 #ifndef __ASSEMBLY__ @@ -57,16 +55,10 @@ #define ARCH_DMA_MINALIGN L1_CACHE_BYTES -/* - * ARC700 doesn't cache any access in top 256M. - * Ideal for wiring memory mapped peripherals as we don't need to do - * explicit uncached accesses (LD.di/ST.di) hence more portable drivers - */ -#define ARC_UNCACHED_ADDR_SPACE 0xc0000000 - extern void arc_cache_init(void); extern char *arc_cache_mumbojumbo(int cpu_id, char *buf, int len); extern void __init read_decode_cache_bcr(void); -#endif + +#endif /* !__ASSEMBLY__ */ #endif /* _ASM_CACHE_H */ diff --git a/arch/arc/include/asm/cacheflush.h b/arch/arc/include/asm/cacheflush.h index ef62682e8d9..6abc4972bc9 100644 --- a/arch/arc/include/asm/cacheflush.h +++ b/arch/arc/include/asm/cacheflush.h @@ -81,16 +81,19 @@ void flush_anon_page(struct vm_area_struct *vma, #endif /* CONFIG_ARC_CACHE_VIPT_ALIASING */ /* + * A new pagecache page has PG_arch_1 clear - thus dcache dirty by default + * This works around some PIO based drivers which don't call flush_dcache_page + * to record that they dirtied the dcache + */ +#define PG_dc_clean PG_arch_1 + +/* * Simple wrapper over config option * Bootup code ensures that hardware matches kernel configuration */ static inline int cache_is_vipt_aliasing(void) { -#ifdef CONFIG_ARC_CACHE_VIPT_ALIASING - return 1; -#else - return 0; -#endif + return IS_ENABLED(CONFIG_ARC_CACHE_VIPT_ALIASING); } #define CACHE_COLOR(addr) (((unsigned long)(addr) >> (PAGE_SHIFT)) & 1) diff --git a/arch/arc/include/asm/defines.h b/arch/arc/include/asm/defines.h deleted file mode 100644 index 6097bb439cc..00000000000 --- a/arch/arc/include/asm/defines.h +++ /dev/null @@ -1,56 +0,0 @@ -/* - * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ - -#ifndef __ARC_ASM_DEFINES_H__ -#define __ARC_ASM_DEFINES_H__ - -#if defined(CONFIG_ARC_MMU_V1) -#define CONFIG_ARC_MMU_VER 1 -#elif defined(CONFIG_ARC_MMU_V2) -#define CONFIG_ARC_MMU_VER 2 -#elif defined(CONFIG_ARC_MMU_V3) -#define CONFIG_ARC_MMU_VER 3 -#endif - -#ifdef CONFIG_ARC_HAS_LLSC -#define __CONFIG_ARC_HAS_LLSC_VAL 1 -#else -#define __CONFIG_ARC_HAS_LLSC_VAL 0 -#endif - -#ifdef CONFIG_ARC_HAS_SWAPE -#define __CONFIG_ARC_HAS_SWAPE_VAL 1 -#else -#define __CONFIG_ARC_HAS_SWAPE_VAL 0 -#endif - -#ifdef CONFIG_ARC_HAS_RTSC -#define __CONFIG_ARC_HAS_RTSC_VAL 1 -#else -#define __CONFIG_ARC_HAS_RTSC_VAL 0 -#endif - -#ifdef CONFIG_ARC_MMU_SASID -#define __CONFIG_ARC_MMU_SASID_VAL 1 -#else -#define __CONFIG_ARC_MMU_SASID_VAL 0 -#endif - -#ifdef CONFIG_ARC_HAS_ICACHE -#define __CONFIG_ARC_HAS_ICACHE 1 -#else -#define __CONFIG_ARC_HAS_ICACHE 0 -#endif - -#ifdef CONFIG_ARC_HAS_DCACHE -#define __CONFIG_ARC_HAS_DCACHE 1 -#else -#define __CONFIG_ARC_HAS_DCACHE 0 -#endif - -#endif /* __ARC_ASM_DEFINES_H__ */ diff --git a/arch/arc/include/asm/entry.h b/arch/arc/include/asm/entry.h index eb2ae53187d..8943c028d4b 100644 --- a/arch/arc/include/asm/entry.h +++ b/arch/arc/include/asm/entry.h @@ -50,194 +50,177 @@ * Eff Addr for load = [reg2] */ +.macro PUSH reg + st.a \reg, [sp, -4] +.endm + +.macro PUSHAX aux + lr r9, [\aux] + PUSH r9 +.endm + +.macro POP reg + ld.ab \reg, [sp, 4] +.endm + +.macro POPAX aux + POP r9 + sr r9, [\aux] +.endm + /*-------------------------------------------------------------- - * Save caller saved registers (scratch registers) ( r0 - r12 ) - * Registers are pushed / popped in the order defined in struct ptregs - * in asm/ptrace.h + * Helpers to save/restore Scratch Regs: + * used by Interrupt/Exception Prologue/Epilogue *-------------------------------------------------------------*/ -.macro SAVE_CALLER_SAVED - st.a r0, [sp, -4] - st.a r1, [sp, -4] - st.a r2, [sp, -4] - st.a r3, [sp, -4] - st.a r4, [sp, -4] - st.a r5, [sp, -4] - st.a r6, [sp, -4] - st.a r7, [sp, -4] - st.a r8, [sp, -4] - st.a r9, [sp, -4] - st.a r10, [sp, -4] - st.a r11, [sp, -4] - st.a r12, [sp, -4] +.macro SAVE_R0_TO_R12 + PUSH r0 + PUSH r1 + PUSH r2 + PUSH r3 + PUSH r4 + PUSH r5 + PUSH r6 + PUSH r7 + PUSH r8 + PUSH r9 + PUSH r10 + PUSH r11 + PUSH r12 +.endm + +.macro RESTORE_R12_TO_R0 + POP r12 + POP r11 + POP r10 + POP r9 + POP r8 + POP r7 + POP r6 + POP r5 + POP r4 + POP r3 + POP r2 + POP r1 + POP r0 + +#ifdef CONFIG_ARC_CURR_IN_REG + ld r25, [sp, 12] +#endif .endm /*-------------------------------------------------------------- - * Restore caller saved registers (scratch registers) + * Helpers to save/restore callee-saved regs: + * used by several macros below *-------------------------------------------------------------*/ -.macro RESTORE_CALLER_SAVED - ld.ab r12, [sp, 4] - ld.ab r11, [sp, 4] - ld.ab r10, [sp, 4] - ld.ab r9, [sp, 4] - ld.ab r8, [sp, 4] - ld.ab r7, [sp, 4] - ld.ab r6, [sp, 4] - ld.ab r5, [sp, 4] - ld.ab r4, [sp, 4] - ld.ab r3, [sp, 4] - ld.ab r2, [sp, 4] - ld.ab r1, [sp, 4] - ld.ab r0, [sp, 4] +.macro SAVE_R13_TO_R24 + PUSH r13 + PUSH r14 + PUSH r15 + PUSH r16 + PUSH r17 + PUSH r18 + PUSH r19 + PUSH r20 + PUSH r21 + PUSH r22 + PUSH r23 + PUSH r24 +.endm + +.macro RESTORE_R24_TO_R13 + POP r24 + POP r23 + POP r22 + POP r21 + POP r20 + POP r19 + POP r18 + POP r17 + POP r16 + POP r15 + POP r14 + POP r13 .endm +#define OFF_USER_R25_FROM_R24 (SZ_CALLEE_REGS + SZ_PT_REGS - 8)/4 /*-------------------------------------------------------------- - * Save callee saved registers (non scratch registers) ( r13 - r25 ) - * on kernel stack. - * User mode callee regs need to be saved in case of - * -fork and friends for replicating from parent to child - * -before going into do_signal( ) for ptrace/core-dump - * Special case handling is required for r25 in case it is used by kernel - * for caching task ptr. Low level exception/ISR save user mode r25 - * into task->thread.user_r25. So it needs to be retrieved from there and - * saved into kernel stack with rest of callee reg-file + * Collect User Mode callee regs as struct callee_regs - needed by + * fork/do_signal/unaligned-access-emulation. + * (By default only scratch regs are saved on entry to kernel) + * + * Special handling for r25 if used for caching Task Pointer. + * It would have been saved in task->thread.user_r25 already, but to keep + * the interface same it is copied into regular r25 placeholder in + * struct callee_regs. *-------------------------------------------------------------*/ .macro SAVE_CALLEE_SAVED_USER - st.a r13, [sp, -4] - st.a r14, [sp, -4] - st.a r15, [sp, -4] - st.a r16, [sp, -4] - st.a r17, [sp, -4] - st.a r18, [sp, -4] - st.a r19, [sp, -4] - st.a r20, [sp, -4] - st.a r21, [sp, -4] - st.a r22, [sp, -4] - st.a r23, [sp, -4] - st.a r24, [sp, -4] + + SAVE_R13_TO_R24 #ifdef CONFIG_ARC_CURR_IN_REG ; Retrieve orig r25 and save it on stack - ld r12, [r25, TASK_THREAD + THREAD_USER_R25] + ld.as r12, [sp, OFF_USER_R25_FROM_R24] st.a r12, [sp, -4] #else - st.a r25, [sp, -4] + PUSH r25 #endif - /* move up by 1 word to "create" callee_regs->"stack_place_holder" */ - sub sp, sp, 4 .endm /*-------------------------------------------------------------- - * Save callee saved registers (non scratch registers) ( r13 - r25 ) - * kernel mode callee regs needed to be saved in case of context switch - * If r25 is used for caching task pointer then that need not be saved - * as it can be re-created from current task global + * Save kernel Mode callee regs at the time of Contect Switch. + * + * Special handling for r25 if used for caching Task Pointer. + * Kernel simply skips saving it since it will be loaded with + * incoming task pointer anyways *-------------------------------------------------------------*/ .macro SAVE_CALLEE_SAVED_KERNEL - st.a r13, [sp, -4] - st.a r14, [sp, -4] - st.a r15, [sp, -4] - st.a r16, [sp, -4] - st.a r17, [sp, -4] - st.a r18, [sp, -4] - st.a r19, [sp, -4] - st.a r20, [sp, -4] - st.a r21, [sp, -4] - st.a r22, [sp, -4] - st.a r23, [sp, -4] - st.a r24, [sp, -4] + + SAVE_R13_TO_R24 + #ifdef CONFIG_ARC_CURR_IN_REG - sub sp, sp, 8 -#else - st.a r25, [sp, -4] < |