[PATCH] drm/xe: Label RING_CONTEXT_CONTROL as masked

[Lucas De Marchi]

On Wed, Apr 03, 2024 at 02:02:07PM -0700, Ashutosh Dixit wrote:
>RING_CONTEXT_CONTROL is a masked register.
>
>Signed-off-by: Ashutosh Dixit <ashutosh.dixit at intel.com>

Due to the way we end up using it, it's not a problem right now:

drivers/gpu/drm/xe/xe_lrc.c-static void set_context_control(u32 *regs, struct xe_hw_engine *hwe)
drivers/gpu/drm/xe/xe_lrc.c-{
drivers/gpu/drm/xe/xe_lrc.c-    regs[CTX_CONTEXT_CONTROL] = _MASKED_BIT_ENABLE(CTX_CTRL_INHIBIT_SYN_CTX_SWITCH) |
drivers/gpu/drm/xe/xe_lrc.c:                                _MASKED_BIT_DISABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT) |
drivers/gpu/drm/xe/xe_lrc.c:                                CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT;

it doesn't really use the  masked flag from the register.
For consistency, and if we ever change the approach, it does look good.

Reviewed-by: Lucas De Marchi <lucas.demarchi at intel.com>

That _MASKED_BIT_DISABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT) |
CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT looks odd. Commit
b4b9457ae9b619c106ee464c3d75ee52c0b69575 (from xe brach, not drm-xe)
blames me while refactoring set_context_control() that always received
true as argument (heheh... commit message from those early days were a
piece of art). Could you prep a patch on top changing that to
ENABLE()?

thanks
Lucas De Marchi

>---
> drivers/gpu/drm/xe/regs/xe_engine_regs.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
>diff --git a/drivers/gpu/drm/xe/regs/xe_engine_regs.h b/drivers/gpu/drm/xe/regs/xe_engine_regs.h
>index a08528d9c76b..af71b87d8030 100644
>--- a/drivers/gpu/drm/xe/regs/xe_engine_regs.h
>+++ b/drivers/gpu/drm/xe/regs/xe_engine_regs.h
>@@ -122,7 +122,7 @@
> #define RING_EXECLIST_STATUS_LO(base)		XE_REG((base) + 0x234)
> #define RING_EXECLIST_STATUS_HI(base)		XE_REG((base) + 0x234 + 4)
>
>-#define RING_CONTEXT_CONTROL(base)		XE_REG((base) + 0x244)
>+#define RING_CONTEXT_CONTROL(base)		XE_REG((base) + 0x244, XE_REG_OPTION_MASKED)
> #define	  CTX_CTRL_INHIBIT_SYN_CTX_SWITCH	REG_BIT(3)
> #define	  CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT	REG_BIT(0)
>
>-- 
>2.41.0
>