diff options
Diffstat (limited to 'drivers/gpu/drm/xe/xe_configfs.c')
| -rw-r--r-- | drivers/gpu/drm/xe/xe_configfs.c | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/drivers/gpu/drm/xe/xe_configfs.c b/drivers/gpu/drm/xe/xe_configfs.c index 8a9b950e7a6d..139663423185 100644 --- a/drivers/gpu/drm/xe/xe_configfs.c +++ b/drivers/gpu/drm/xe/xe_configfs.c @@ -126,8 +126,20 @@ * not intended for normal execution and will taint the kernel with TAINT_TEST * when used. * - * Currently this is implemented only for post and mid context restore. - * Examples: + * The syntax allows to pass straight instructions to be executed by the engine + * in a batch buffer or set specific registers. + * + * #. Generic instruction:: + * + * <engine-class> cmd <instr> [[dword0] [dword1] [...]] + * + * #. Simple register setting:: + * + * <engine-class> reg <address> <value> + * + * Commands are saved per engine class: all instances of that class will execute + * those commands during context switch. The instruction, dword arguments, + * addresses and values are in hex format like in the examples below. * * #. Execute a LRI command to write 0xDEADBEEF to register 0x4f10 after the * normal context restore:: @@ -154,7 +166,8 @@ * When using multiple lines, make sure to use a command that is * implemented with a single write syscall, like HEREDOC. * - * These attributes can only be set before binding to the device. + * Currently this is implemented only for post and mid context restore and + * these attributes can only be set before binding to the device. * * Remove devices * ============== @@ -324,8 +337,8 @@ static const struct engine_info *lookup_engine_info(const char *pattern, u64 *ma continue; pattern += strlen(engine_info[i].cls); - if (!mask && !*pattern) - return &engine_info[i]; + if (!mask) + return *pattern ? NULL : &engine_info[i]; if (!strcmp(pattern, "*")) { *mask = engine_info[i].mask; |