drm/xe/xe2: Add workaround 16020183090

Graphics version 20.04, used in Lunar Lake, needs WA 16020183090 for
steppings A*. Set ENABLE_SEMAPHORE_POLL_BIT in INSTPM(RENDER_RING_BASE)
and whitelist CSBE_DEBUG_STATUS for userspace to be able to use it
and complement the workaround.

Cc: Haridhar Kalvala <haridhar.kalvala@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://lore.kernel.org/r/20231207175117.2334022-1-lucas.demarchi@intel.comSigned-off-by: Lucas De Marchi <lucas.demarchi@intel.com>

drivers/gpu/drm/xe/regs/xe_engine_regs.h

@@ -83,6 +83,9 @@
 #define RING_EMR(base)				XE_REG((base) + 0xb4)
 #define RING_ESR(base)				XE_REG((base) + 0xb8)
 
+#define INSTPM(base)				XE_REG((base) + 0xc0, XE_REG_OPTION_MASKED)
+#define   ENABLE_SEMAPHORE_POLL_BIT		REG_BIT(13)
+
 #define RING_CMD_CCTL(base)			XE_REG((base) + 0xc4, XE_REG_OPTION_MASKED)
 /*
  * CMD_CCTL read/write fields take a MOCS value and _not_ a table index.
@@ -138,6 +141,7 @@
 #define   TAIL_ADDR				0x001FFFF8
 
 #define RING_CTX_TIMESTAMP(base)		XE_REG((base) + 0x3a8)
+#define CSBE_DEBUG_STATUS(base)			XE_REG((base) + 0x3fc)
 
 #define RING_FORCE_TO_NONPRIV(base, i)		XE_REG(((base) + 0x4d0) + (i) * 4)
 #define   RING_FORCE_TO_NONPRIV_DENY		REG_BIT(30)

drivers/gpu/drm/xe/xe_reg_whitelist.c

@@ -7,9 +7,11 @@
 
 #include "regs/xe_engine_regs.h"
 #include "regs/xe_gt_regs.h"
+#include "regs/xe_regs.h"
 #include "xe_gt_types.h"
 #include "xe_platform_types.h"
 #include "xe_rtp.h"
+#include "xe_step.h"
 
 #undef XE_REG_MCR
 #define XE_REG_MCR(...)     XE_REG(__VA_ARGS__, .mcr = 1)
@@ -56,6 +58,12 @@ static const struct xe_rtp_entry_sr register_whitelist[] = {
 				   RING_FORCE_TO_NONPRIV_DENY,
 				   XE_RTP_ACTION_FLAG(ENGINE_BASE)))
 	},
+	{ XE_RTP_NAME("16020183090"),
+	  XE_RTP_RULES(GRAPHICS_VERSION(2004), GRAPHICS_STEP(A0, B0),
+		       ENGINE_CLASS(RENDER)),
+	  XE_RTP_ACTIONS(WHITELIST(CSBE_DEBUG_STATUS(RENDER_RING_BASE), 0))
+	},
+
 	{}
 };
 

drivers/gpu/drm/xe/xe_wa.c

@@ -571,6 +571,11 @@ static const struct xe_rtp_entry_sr lrc_was[] = {
 	  XE_RTP_RULES(GRAPHICS_VERSION(2004), ENGINE_CLASS(RENDER)),
 	  XE_RTP_ACTIONS(SET(XEHP_PSS_CHICKEN, FLSH_IGNORES_PSD))
 	},
+	{ XE_RTP_NAME("16020183090"),
+	  XE_RTP_RULES(GRAPHICS_VERSION(2004), GRAPHICS_STEP(A0, B0),
+		       ENGINE_CLASS(RENDER)),
+	  XE_RTP_ACTIONS(SET(INSTPM(RENDER_RING_BASE), ENABLE_SEMAPHORE_POLL_BIT))
+	},
 
 	{}
 };