diff options
author | Max Filippov <jcmvbkbc@gmail.com> | 2023-07-11 00:13:27 +0200 |
---|---|---|
committer | Max Filippov <jcmvbkbc@gmail.com> | 2023-07-11 06:41:04 +0200 |
commit | a160e9414d8a1747225206558b24d7df513b3c8d (patch) | |
tree | 6c50ed03f217f1253c7d80272494958d62b43cd1 /arch/xtensa/kernel | |
parent | xtensa: ISS: fix call to split_if_spec (diff) | |
download | linux-a160e9414d8a1747225206558b24d7df513b3c8d.tar.xz linux-a160e9414d8a1747225206558b24d7df513b3c8d.zip |
xtensa: fix unaligned and load/store configuration interaction
Unaligned exception handler is needed in configurations with hardware
support for unaligned access when the load/store exception handler is
enabled because such configurations would still raise an exception on
unaligned access through the instruction bus.
Fixes: f29cf77609cc ("xtensa: add load/store exception handler")
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Diffstat (limited to 'arch/xtensa/kernel')
-rw-r--r-- | arch/xtensa/kernel/align.S | 34 | ||||
-rw-r--r-- | arch/xtensa/kernel/traps.c | 3 |
2 files changed, 16 insertions, 21 deletions
diff --git a/arch/xtensa/kernel/align.S b/arch/xtensa/kernel/align.S index 20d6b4961001..ee97edce2300 100644 --- a/arch/xtensa/kernel/align.S +++ b/arch/xtensa/kernel/align.S @@ -1,7 +1,7 @@ /* * arch/xtensa/kernel/align.S * - * Handle unalignment exceptions in kernel space. + * Handle unalignment and load/store exceptions. * * This file is subject to the terms and conditions of the GNU General * Public License. See the file "COPYING" in the main directory of @@ -26,20 +26,18 @@ #define LOAD_EXCEPTION_HANDLER #endif -#if XCHAL_UNALIGNED_STORE_EXCEPTION || defined LOAD_EXCEPTION_HANDLER +#if XCHAL_UNALIGNED_STORE_EXCEPTION || defined CONFIG_XTENSA_LOAD_STORE +#define STORE_EXCEPTION_HANDLER +#endif + +#if defined LOAD_EXCEPTION_HANDLER || defined STORE_EXCEPTION_HANDLER #define ANY_EXCEPTION_HANDLER #endif -#if XCHAL_HAVE_WINDOWED +#if XCHAL_HAVE_WINDOWED && defined CONFIG_MMU #define UNALIGNED_USER_EXCEPTION #endif -/* First-level exception handler for unaligned exceptions. - * - * Note: This handler works only for kernel exceptions. Unaligned user - * access should get a seg fault. - */ - /* Big and little endian 16-bit values are located in * different halves of a register. HWORD_START helps to * abstract the notion of extracting a 16-bit value from a @@ -228,8 +226,6 @@ ENDPROC(fast_load_store) #ifdef ANY_EXCEPTION_HANDLER ENTRY(fast_unaligned) -#if XCHAL_UNALIGNED_LOAD_EXCEPTION || XCHAL_UNALIGNED_STORE_EXCEPTION - call0 .Lsave_and_load_instruction /* Analyze the instruction (load or store?). */ @@ -244,8 +240,7 @@ ENTRY(fast_unaligned) /* 'store indicator bit' not set, jump */ _bbci.l a4, OP1_SI_BIT + INSN_OP1, .Lload -#endif -#if XCHAL_UNALIGNED_STORE_EXCEPTION +#ifdef STORE_EXCEPTION_HANDLER /* Store: Jump to table entry to get the value in the source register.*/ @@ -254,7 +249,7 @@ ENTRY(fast_unaligned) addx8 a5, a6, a5 jx a5 # jump into table #endif -#if XCHAL_UNALIGNED_LOAD_EXCEPTION +#ifdef LOAD_EXCEPTION_HANDLER /* Load: Load memory address. */ @@ -328,7 +323,7 @@ ENTRY(fast_unaligned) mov a14, a3 ; _j .Lexit; .align 8 mov a15, a3 ; _j .Lexit; .align 8 #endif -#if XCHAL_UNALIGNED_STORE_EXCEPTION +#ifdef STORE_EXCEPTION_HANDLER .Lstore_table: l32i a3, a2, PT_AREG0; _j .Lstore_w; .align 8 mov a3, a1; _j .Lstore_w; .align 8 # fishy?? @@ -348,7 +343,6 @@ ENTRY(fast_unaligned) mov a3, a15 ; _j .Lstore_w; .align 8 #endif -#ifdef ANY_EXCEPTION_HANDLER /* We cannot handle this exception. */ .extern _kernel_exception @@ -377,8 +371,8 @@ ENTRY(fast_unaligned) 2: movi a0, _user_exception jx a0 -#endif -#if XCHAL_UNALIGNED_STORE_EXCEPTION + +#ifdef STORE_EXCEPTION_HANDLER # a7: instruction pointer, a4: instruction, a3: value .Lstore_w: @@ -444,7 +438,7 @@ ENTRY(fast_unaligned) s32i a6, a4, 4 #endif #endif -#ifdef ANY_EXCEPTION_HANDLER + .Lexit: #if XCHAL_HAVE_LOOPS rsr a4, lend # check if we reached LEND @@ -539,7 +533,7 @@ ENTRY(fast_unaligned) __src_b a4, a4, a5 # a4 has the instruction ret -#endif + ENDPROC(fast_unaligned) ENTRY(fast_unaligned_fixup) diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c index 17eb180eff7c..427c125a137a 100644 --- a/arch/xtensa/kernel/traps.c +++ b/arch/xtensa/kernel/traps.c @@ -102,7 +102,8 @@ static dispatch_init_table_t __initdata dispatch_init_table[] = { #endif { EXCCAUSE_INTEGER_DIVIDE_BY_ZERO, 0, do_div0 }, /* EXCCAUSE_PRIVILEGED unhandled */ -#if XCHAL_UNALIGNED_LOAD_EXCEPTION || XCHAL_UNALIGNED_STORE_EXCEPTION +#if XCHAL_UNALIGNED_LOAD_EXCEPTION || XCHAL_UNALIGNED_STORE_EXCEPTION || \ + IS_ENABLED(CONFIG_XTENSA_LOAD_STORE) #ifdef CONFIG_XTENSA_UNALIGNED_USER { EXCCAUSE_UNALIGNED, USER, fast_unaligned }, #endif |