From c658eac628aa8df040dfe614556d95e6da3a9ffb Mon Sep 17 00:00:00 2001 From: Chris Zankel Date: Tue, 12 Feb 2008 13:17:07 -0800 Subject: [XTENSA] Add support for configurable registers and coprocessors The Xtensa architecture allows to define custom instructions and registers. Registers that are bound to a coprocessor are only accessible if the corresponding enable bit is set, which allows to implement a 'lazy' context switch mechanism. Other registers needs to be saved and restore at the time of the context switch or during interrupt handling. This patch adds support for these additional states: - save and restore registers that are used by the compiler upon interrupt entry and exit. - context switch additional registers unbound to any coprocessor - 'lazy' context switch of registers bound to a coprocessor - ptrace interface to provide access to additional registers - update configuration files in include/asm-xtensa/variant-fsf Signed-off-by: Chris Zankel --- include/asm-xtensa/processor.h | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) (limited to 'include/asm-xtensa/processor.h') diff --git a/include/asm-xtensa/processor.h b/include/asm-xtensa/processor.h index 96408f436624..4918a4e96d42 100644 --- a/include/asm-xtensa/processor.h +++ b/include/asm-xtensa/processor.h @@ -103,10 +103,6 @@ struct thread_struct { unsigned long dbreaka[XCHAL_NUM_DBREAK]; unsigned long dbreakc[XCHAL_NUM_DBREAK]; - /* Allocate storage for extra state and coprocessor state. */ - unsigned char cp_save[XTENSA_CP_EXTRA_SIZE] - __attribute__ ((aligned(XTENSA_CP_EXTRA_ALIGN))); - /* Make structure 16 bytes aligned. */ int align[0] __attribute__ ((aligned(16))); }; @@ -162,21 +158,16 @@ struct thread_struct { struct task_struct; struct mm_struct; -// FIXME: do we need release_thread for CP?? /* Free all resources held by a thread. */ #define release_thread(thread) do { } while(0) -// FIXME: do we need prepare_to_copy (lazy status) for CP?? /* Prepare to copy thread state - unlazy all lazy status */ -#define prepare_to_copy(tsk) do { } while (0) +extern void prepare_to_copy(struct task_struct*); -/* - * create a kernel thread without removing it from tasklists - */ +/* Create a kernel thread without removing it from tasklists */ extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags); /* Copy and release all segment info associated with a VM */ - #define copy_segments(p, mm) do { } while(0) #define release_segments(mm) do { } while(0) #define forget_segments() do { } while (0) -- cgit v1.2.3