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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-08 04:21:35 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-08 04:21:35 +0000 |
commit | 7b642cd94bb96385cbdbb36a1952f129af6b1bbb (patch) | |
tree | e7c4209372da8a2fa745aaa3e99d062e54d0f556 /arch/arc/include/asm | |
parent | Adding debian version 4.19.289-2. (diff) | |
download | linux-7b642cd94bb96385cbdbb36a1952f129af6b1bbb.tar.xz linux-7b642cd94bb96385cbdbb36a1952f129af6b1bbb.zip |
Merging upstream version 4.19.304.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arc/include/asm')
-rw-r--r-- | arch/arc/include/asm/entry-arcv2.h | 362 | ||||
-rw-r--r-- | arch/arc/include/asm/linkage.h | 22 |
2 files changed, 211 insertions, 173 deletions
diff --git a/arch/arc/include/asm/entry-arcv2.h b/arch/arc/include/asm/entry-arcv2.h index 225e7df2d..0733752ce 100644 --- a/arch/arc/include/asm/entry-arcv2.h +++ b/arch/arc/include/asm/entry-arcv2.h @@ -7,232 +7,252 @@ #include <asm/irqflags-arcv2.h> #include <asm/thread_info.h> /* For THREAD_SIZE */ +/* + * Interrupt/Exception stack layout (pt_regs) for ARCv2 + * (End of struct aligned to end of page [unless nested]) + * + * INTERRUPT EXCEPTION + * + * manual --------------------- manual + * | orig_r0 | + * | event/ECR | + * | bta | + * | user_r25 | + * | gp | + * | fp | + * | sp | + * | r12 | + * | r30 | + * | r58 | + * | r59 | + * hw autosave --------------------- + * optional | r0 | + * | r1 | + * ~ ~ + * | r9 | + * | r10 | + * | r11 | + * | blink | + * | lpe | + * | lps | + * | lpc | + * | ei base | + * | ldi base | + * | jli base | + * --------------------- + * hw autosave | pc / eret | + * mandatory | stat32 / erstatus | + * --------------------- + */ + /*------------------------------------------------------------------------*/ -.macro INTERRUPT_PROLOGUE called_from +.macro INTERRUPT_PROLOGUE - ; Before jumping to Interrupt Vector, hardware micro-ops did following: + ; (A) Before jumping to Interrupt Vector, hardware micro-ops did following: ; 1. SP auto-switched to kernel mode stack - ; 2. STATUS32.Z flag set to U mode at time of interrupt (U:1, K:0) - ; 3. Auto saved: r0-r11, blink, LPE,LPS,LPC, JLI,LDI,EI, PC, STAT32 + ; 2. STATUS32.Z flag set if in U mode at time of interrupt (U:1,K:0) + ; 3. Auto save: (mandatory) Push PC and STAT32 on stack + ; hardware does even if CONFIG_ARC_IRQ_NO_AUTOSAVE + ; 4. Auto save: (optional) r0-r11, blink, LPE,LPS,LPC, JLI,LDI,EI ; - ; Now manually save: r12, sp, fp, gp, r25 + ; (B) Manually saved some regs: r12,r25,r30, sp,fp,gp, ACCL pair #ifdef CONFIG_ARC_IRQ_NO_AUTOSAVE -.ifnc \called_from, exception - st.as r9, [sp, -10] ; save r9 in it's final stack slot - sub sp, sp, 12 ; skip JLI, LDI, EI - - PUSH lp_count - PUSHAX lp_start - PUSHAX lp_end - PUSH blink - - PUSH r11 - PUSH r10 - - sub sp, sp, 4 ; skip r9 - - PUSH r8 - PUSH r7 - PUSH r6 - PUSH r5 - PUSH r4 - PUSH r3 - PUSH r2 - PUSH r1 - PUSH r0 -.endif -#endif + ; carve pt_regs on stack (case #3), PC/STAT32 already on stack + sub sp, sp, SZ_PT_REGS - 8 -#ifdef CONFIG_ARC_HAS_ACCL_REGS - PUSH r59 - PUSH r58 + __SAVE_REGFILE_HARD +#else + ; carve pt_regs on stack (case #4), which grew partially already + sub sp, sp, PT_r0 #endif - PUSH r30 - PUSH r12 + __SAVE_REGFILE_SOFT +.endm + +/*------------------------------------------------------------------------*/ +.macro EXCEPTION_PROLOGUE + + ; (A) Before jumping to Exception Vector, hardware micro-ops did following: + ; 1. SP auto-switched to kernel mode stack + ; 2. STATUS32.Z flag set if in U mode at time of exception (U:1,K:0) + ; + ; (B) Manually save the complete reg file below + + sub sp, sp, SZ_PT_REGS ; carve pt_regs + + ; _HARD saves r10 clobbered by _SOFT as scratch hence comes first + + __SAVE_REGFILE_HARD + __SAVE_REGFILE_SOFT + + st r0, [sp] ; orig_r0 + + lr r10, [eret] + lr r11, [erstatus] + ST2 r10, r11, PT_ret + + lr r10, [ecr] + lr r11, [erbta] + ST2 r10, r11, PT_event + mov r9, r10 + + ; OUTPUT: r9 has ECR +.endm + +/*------------------------------------------------------------------------ + * This macro saves the registers manually which would normally be autosaved + * by hardware on taken interrupts. It is used by + * - exception handlers (which don't have autosave) + * - interrupt autosave disabled due to CONFIG_ARC_IRQ_NO_AUTOSAVE + */ +.macro __SAVE_REGFILE_HARD + + ST2 r0, r1, PT_r0 + ST2 r2, r3, PT_r2 + ST2 r4, r5, PT_r4 + ST2 r6, r7, PT_r6 + ST2 r8, r9, PT_r8 + ST2 r10, r11, PT_r10 + + st blink, [sp, PT_blink] + + lr r10, [lp_end] + lr r11, [lp_start] + ST2 r10, r11, PT_lpe + + st lp_count, [sp, PT_lpc] + + ; skip JLI, LDI, EI for now +.endm + +/*------------------------------------------------------------------------ + * This macros saves a bunch of other registers which can't be autosaved for + * various reasons: + * - r12: the last caller saved scratch reg since hardware saves in pairs so r0-r11 + * - r30: free reg, used by gcc as scratch + * - ACCL/ACCH pair when they exist + */ +.macro __SAVE_REGFILE_SOFT + + ST2 gp, fp, PT_r26 ; gp (r26), fp (r27) + + st r12, [sp, PT_sp + 4] + st r30, [sp, PT_sp + 8] ; Saving pt_regs->sp correctly requires some extra work due to the way ; Auto stack switch works ; - U mode: retrieve it from AUX_USER_SP ; - K mode: add the offset from current SP where H/w starts auto push ; - ; Utilize the fact that Z bit is set if Intr taken in U mode - mov.nz r9, sp - add.nz r9, r9, SZ_PT_REGS - PT_sp - 4 - bnz 1f + ; 1. Utilize the fact that Z bit is set if Intr taken in U mode + ; 2. Upon entry SP is always saved (for any inspection, unwinding etc), + ; but on return, restored only if U mode - lr r9, [AUX_USER_SP] -1: - PUSH r9 ; SP + lr r10, [AUX_USER_SP] ; U mode SP + + ; ISA requires ADD.nz to have same dest and src reg operands + mov.nz r10, sp + add.nz r10, r10, SZ_PT_REGS ; K mode SP - PUSH fp - PUSH gp + st r10, [sp, PT_sp] ; SP (pt_regs->sp) #ifdef CONFIG_ARC_CURR_IN_REG - PUSH r25 ; user_r25 + st r25, [sp, PT_user_r25] GET_CURR_TASK_ON_CPU r25 -#else - sub sp, sp, 4 #endif -.ifnc \called_from, exception - sub sp, sp, 12 ; BTA/ECR/orig_r0 placeholder per pt_regs -.endif +#ifdef CONFIG_ARC_HAS_ACCL_REGS + ST2 r58, r59, PT_sp + 12 +#endif .endm /*------------------------------------------------------------------------*/ -.macro INTERRUPT_EPILOGUE called_from +.macro __RESTORE_REGFILE_SOFT -.ifnc \called_from, exception - add sp, sp, 12 ; skip BTA/ECR/orig_r0 placeholderss -.endif + LD2 gp, fp, PT_r26 ; gp (r26), fp (r27) -#ifdef CONFIG_ARC_CURR_IN_REG - POP r25 -#else - add sp, sp, 4 -#endif + ld r12, [sp, PT_sp + 4] + ld r30, [sp, PT_sp + 8] - POP gp - POP fp - - ; Don't touch AUX_USER_SP if returning to K mode (Z bit set) - ; (Z bit set on K mode is inverse of INTERRUPT_PROLOGUE) - add.z sp, sp, 4 + ; Restore SP (into AUX_USER_SP) only if returning to U mode + ; - for K mode, it will be implicitly restored as stack is unwound + ; - Z flag set on K is inverse of what hardware does on interrupt entry + ; but that doesn't really matter bz 1f - POPAX AUX_USER_SP + ld r10, [sp, PT_sp] ; SP (pt_regs->sp) + sr r10, [AUX_USER_SP] 1: - POP r12 - POP r30 -#ifdef CONFIG_ARC_HAS_ACCL_REGS - POP r58 - POP r59 +#ifdef CONFIG_ARC_CURR_IN_REG + ld r25, [sp, PT_user_r25] #endif -#ifdef CONFIG_ARC_IRQ_NO_AUTOSAVE -.ifnc \called_from, exception - POP r0 - POP r1 - POP r2 - POP r3 - POP r4 - POP r5 - POP r6 - POP r7 - POP r8 - POP r9 - POP r10 - POP r11 - - POP blink - POPAX lp_end - POPAX lp_start - - POP r9 - mov lp_count, r9 - - add sp, sp, 12 ; skip JLI, LDI, EI - ld.as r9, [sp, -10] ; reload r9 which got clobbered -.endif +#ifdef CONFIG_ARC_HAS_ACCL_REGS + LD2 r58, r59, PT_sp + 12 #endif +.endm +/*------------------------------------------------------------------------*/ +.macro __RESTORE_REGFILE_HARD + + ld blink, [sp, PT_blink] + + LD2 r10, r11, PT_lpe + sr r10, [lp_end] + sr r11, [lp_start] + + ld r10, [sp, PT_lpc] ; lp_count can't be target of LD + mov lp_count, r10 + + LD2 r0, r1, PT_r0 + LD2 r2, r3, PT_r2 + LD2 r4, r5, PT_r4 + LD2 r6, r7, PT_r6 + LD2 r8, r9, PT_r8 + LD2 r10, r11, PT_r10 .endm + /*------------------------------------------------------------------------*/ -.macro EXCEPTION_PROLOGUE +.macro INTERRUPT_EPILOGUE - ; Before jumping to Exception Vector, hardware micro-ops did following: - ; 1. SP auto-switched to kernel mode stack - ; 2. STATUS32.Z flag set to U mode at time of interrupt (U:1,K:0) - ; - ; Now manually save the complete reg file - - PUSH r9 ; freeup a register: slot of erstatus - - PUSHAX eret - sub sp, sp, 12 ; skip JLI, LDI, EI - PUSH lp_count - PUSHAX lp_start - PUSHAX lp_end - PUSH blink - - PUSH r11 - PUSH r10 - - ld.as r9, [sp, 10] ; load stashed r9 (status32 stack slot) - lr r10, [erstatus] - st.as r10, [sp, 10] ; save status32 at it's right stack slot - - PUSH r9 - PUSH r8 - PUSH r7 - PUSH r6 - PUSH r5 - PUSH r4 - PUSH r3 - PUSH r2 - PUSH r1 - PUSH r0 - - ; -- for interrupts, regs above are auto-saved by h/w in that order -- - ; Now do what ISR prologue does (manually save r12, sp, fp, gp, r25) - ; - ; Set Z flag if this was from U mode (expected by INTERRUPT_PROLOGUE) - ; Although H/w exception micro-ops do set Z flag for U mode (just like - ; for interrupts), it could get clobbered in case we soft land here from - ; a TLB Miss exception handler (tlbex.S) + ; INPUT: r0 has STAT32 of calling context + ; INPUT: Z flag set if returning to K mode - and r10, r10, STATUS_U_MASK - xor.f 0, r10, STATUS_U_MASK + ; _SOFT clobbers r10 restored by _HARD hence the order - INTERRUPT_PROLOGUE exception + __RESTORE_REGFILE_SOFT - PUSHAX erbta - PUSHAX ecr ; r9 contains ECR, expected by EV_Trap +#ifdef CONFIG_ARC_IRQ_NO_AUTOSAVE + __RESTORE_REGFILE_HARD + add sp, sp, SZ_PT_REGS - 8 +#else + add sp, sp, PT_r0 +#endif - PUSH r0 ; orig_r0 .endm /*------------------------------------------------------------------------*/ .macro EXCEPTION_EPILOGUE - ; Assumes r0 has PT_status32 - btst r0, STATUS_U_BIT ; Z flag set if K, used in INTERRUPT_EPILOGUE - - add sp, sp, 8 ; orig_r0/ECR don't need restoring - POPAX erbta - - INTERRUPT_EPILOGUE exception + ; INPUT: r0 has STAT32 of calling context - POP r0 - POP r1 - POP r2 - POP r3 - POP r4 - POP r5 - POP r6 - POP r7 - POP r8 - POP r9 - POP r10 - POP r11 + btst r0, STATUS_U_BIT ; Z flag set if K, used in restoring SP - POP blink - POPAX lp_end - POPAX lp_start + ld r10, [sp, PT_event + 4] + sr r10, [erbta] - POP r9 - mov lp_count, r9 + LD2 r10, r11, PT_ret + sr r10, [eret] + sr r11, [erstatus] - add sp, sp, 12 ; skip JLI, LDI, EI - POPAX eret - POPAX erstatus + __RESTORE_REGFILE_SOFT + __RESTORE_REGFILE_HARD - ld.as r9, [sp, -12] ; reload r9 which got clobbered + add sp, sp, SZ_PT_REGS .endm .macro FAKE_RET_FROM_EXCPN diff --git a/arch/arc/include/asm/linkage.h b/arch/arc/include/asm/linkage.h index 07c8e1a6c..b89ca8b4d 100644 --- a/arch/arc/include/asm/linkage.h +++ b/arch/arc/include/asm/linkage.h @@ -11,12 +11,30 @@ #include <asm/dwarf.h> -#ifdef __ASSEMBLY__ - #define ASM_NL ` /* use '`' to mark new line in macro */ #define __ALIGN .align 4 #define __ALIGN_STR __stringify(__ALIGN) +#ifdef __ASSEMBLY__ + +.macro ST2 e, o, off +#ifdef CONFIG_ARC_HAS_LL64 + std \e, [sp, \off] +#else + st \e, [sp, \off] + st \o, [sp, \off+4] +#endif +.endm + +.macro LD2 e, o, off +#ifdef CONFIG_ARC_HAS_LL64 + ldd \e, [sp, \off] +#else + ld \e, [sp, \off] + ld \o, [sp, \off+4] +#endif +.endm + /* annotation for data we want in DCCM - if enabled in .config */ .macro ARCFP_DATA nm #ifdef CONFIG_ARC_HAS_DCCM |