drm/i915: Define multicast registers as a new type

Rather than treating multicast registers as 'i915_reg_t' let's define
them as a completely new type.  This will allow the compiler to help us
make sure we're using multicast-aware functions to operate on multicast
registers.

This plan does break down a bit in places where we're just maintaining
heterogeneous lists of registers (e.g., various MMIO whitelists used by
perf, GVT, etc.) rather than performing reads/writes.  We only really
care about the offset in those cases, so for now we can "cast" the
registers as non-MCR, leaving us with a list of i915_reg_t's, but we may
want to look for better ways to store mixed collections of i915_reg_t
and i915_mcr_reg_t in the future.

v2:
 - Add TLB invalidation registers
v3:
 - Make type checking of i915_mmio_reg_offset() stricter.  It will
   accept either i915_reg_t or i915_mcr_reg_t, but will now raise a
   compile error if any other type is passed, even if that type contains
   a 'reg' field.  (Jani)
 - Drop a ton of GVT changes; allowing i915_mmio_reg_offset() to take
   either an i915_reg_t or an i915_mcr_reg_t means that the huge lists
   of MMIO_D*() macros used in GVT will continue to work without
   modification.  We need only make changes to structures that have an
   explicit i915_reg_t in them now.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221014230239.1023689-13-matthew.d.roper@intel.com

12 files changed, 117 insertions, 83 deletions

diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
index 3df0d0336dbc..27dbb9e4bd6c 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt.c
@@ -991,7 +991,10 @@ void intel_gt_info_print(const struct intel_gt_info *info,
 }
 
 struct reg_and_bit {
-	i915_reg_t reg;
+	union {
+		i915_reg_t reg;
+		i915_mcr_reg_t mcr_reg;
+	};
 	u32 bit;
 };
 
@@ -1033,7 +1036,7 @@ get_reg_and_bit(const struct intel_engine_cs *engine, const bool gen8,
 static int wait_for_invalidate(struct intel_gt *gt, struct reg_and_bit rb)
 {
 	if (GRAPHICS_VER_FULL(gt->i915) >= IP_VER(12, 50))
-		return intel_gt_mcr_wait_for_reg_fw(gt, rb.reg, rb.bit, 0,
+		return intel_gt_mcr_wait_for_reg_fw(gt, rb.mcr_reg, rb.bit, 0,
 						    TLB_INVAL_TIMEOUT_US,
 						    TLB_INVAL_TIMEOUT_MS);
 	else
@@ -1058,7 +1061,7 @@ static void mmio_invalidate_full(struct intel_gt *gt)
 		[COPY_ENGINE_CLASS]		= GEN12_BLT_TLB_INV_CR,
 		[COMPUTE_CLASS]			= GEN12_COMPCTX_TLB_INV_CR,
 	};
-	static const i915_reg_t xehp_regs[] = {
+	static const i915_mcr_reg_t xehp_regs[] = {
 		[RENDER_CLASS]			= XEHP_GFX_TLB_INV_CR,
 		[VIDEO_DECODE_CLASS]		= XEHP_VD_TLB_INV_CR,
 		[VIDEO_ENHANCEMENT_CLASS]	= XEHP_VE_TLB_INV_CR,
@@ -1131,7 +1134,12 @@ static void mmio_invalidate_full(struct intel_gt *gt)
 	for_each_engine_masked(engine, gt, awake, tmp) {
 		struct reg_and_bit rb;
 
-		rb = get_reg_and_bit(engine, regs == gen8_regs, regs, num);
+		if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50)) {
+			rb.mcr_reg = xehp_regs[engine->class];
+			rb.bit = BIT(engine->instance);
+		} else {
+			rb = get_reg_and_bit(engine, regs == gen8_regs, regs, num);
+		}
 
 		if (wait_for_invalidate(gt, rb))
 			drm_err_ratelimited(&gt->i915->drm,
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_mcr.c b/drivers/gpu/drm/i915/gt/intel_gt_mcr.c
index 1ed9bc4dccfd..349074bf365f 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_mcr.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt_mcr.c
@@ -151,6 +151,19 @@ void intel_gt_mcr_init(struct intel_gt *gt)
 }
 
 /*
+ * Although the rest of the driver should use MCR-specific functions to
+ * read/write MCR registers, we still use the regular intel_uncore_* functions
+ * internally to implement those, so we need a way for the functions in this
+ * file to "cast" an i915_mcr_reg_t into an i915_reg_t.
+ */
+static i915_reg_t mcr_reg_cast(const i915_mcr_reg_t mcr)
+{
+	i915_reg_t r = { .reg = mcr.reg };
+
+	return r;
+}
+
+/*
  * rw_with_mcr_steering_fw - Access a register with specific MCR steering
  * @uncore: pointer to struct intel_uncore
  * @reg: register being accessed
@@ -164,7 +177,7 @@ void intel_gt_mcr_init(struct intel_gt *gt)
  * Caller needs to make sure the relevant forcewake wells are up.
  */
 static u32 rw_with_mcr_steering_fw(struct intel_uncore *uncore,
-				   i915_reg_t reg, u8 rw_flag,
+				   i915_mcr_reg_t reg, u8 rw_flag,
 				   int group, int instance, u32 value)
 {
 	u32 mcr_mask, mcr_ss, mcr, old_mcr, val = 0;
@@ -201,9 +214,9 @@ static u32 rw_with_mcr_steering_fw(struct intel_uncore *uncore,
 	intel_uncore_write_fw(uncore, GEN8_MCR_SELECTOR, mcr);
 
 	if (rw_flag == FW_REG_READ)
-		val = intel_uncore_read_fw(uncore, reg);
+		val = intel_uncore_read_fw(uncore, mcr_reg_cast(reg));
 	else
-		intel_uncore_write_fw(uncore, reg, value);
+		intel_uncore_write_fw(uncore, mcr_reg_cast(reg), value);
 
 	mcr &= ~mcr_mask;
 	mcr |= old_mcr & mcr_mask;
@@ -214,14 +227,14 @@ static u32 rw_with_mcr_steering_fw(struct intel_uncore *uncore,
 }
 
 static u32 rw_with_mcr_steering(struct intel_uncore *uncore,
-				i915_reg_t reg, u8 rw_flag,
+				i915_mcr_reg_t reg, u8 rw_flag,
 				int group, int instance,
 				u32 value)
 {
 	enum forcewake_domains fw_domains;
 	u32 val;
 
-	fw_domains = intel_uncore_forcewake_for_reg(uncore, reg,
+	fw_domains = intel_uncore_forcewake_for_reg(uncore, mcr_reg_cast(reg),
 						    rw_flag);
 	fw_domains |= intel_uncore_forcewake_for_reg(uncore,
 						     GEN8_MCR_SELECTOR,
@@ -249,7 +262,7 @@ static u32 rw_with_mcr_steering(struct intel_uncore *uncore,
  * group/instance.
  */
 u32 intel_gt_mcr_read(struct intel_gt *gt,
-		      i915_reg_t reg,
+		      i915_mcr_reg_t reg,
 		      int group, int instance)
 {
 	return rw_with_mcr_steering(gt->uncore, reg, FW_REG_READ, group, instance, 0);
@@ -266,7 +279,7 @@ u32 intel_gt_mcr_read(struct intel_gt *gt,
  * Write an MCR register in unicast mode after steering toward a specific
  * group/instance.
  */
-void intel_gt_mcr_unicast_write(struct intel_gt *gt, i915_reg_t reg, u32 value,
+void intel_gt_mcr_unicast_write(struct intel_gt *gt, i915_mcr_reg_t reg, u32 value,
 				int group, int instance)
 {
 	rw_with_mcr_steering(gt->uncore, reg, FW_REG_WRITE, group, instance, value);
@@ -281,9 +294,9 @@ void intel_gt_mcr_unicast_write(struct intel_gt *gt, i915_reg_t reg, u32 value,
  * Write an MCR register in multicast mode to update all instances.
  */
 void intel_gt_mcr_multicast_write(struct intel_gt *gt,
-				i915_reg_t reg, u32 value)
+				  i915_mcr_reg_t reg, u32 value)
 {
-	intel_uncore_write(gt->uncore, reg, value);
+	intel_uncore_write(gt->uncore, mcr_reg_cast(reg), value);
 }
 
 /**
@@ -297,9 +310,9 @@ void intel_gt_mcr_multicast_write(struct intel_gt *gt,
  * domains; use intel_gt_mcr_multicast_write() in cases where forcewake should
  * be obtained automatically.
  */
-void intel_gt_mcr_multicast_write_fw(struct intel_gt *gt, i915_reg_t reg, u32 value)
+void intel_gt_mcr_multicast_write_fw(struct intel_gt *gt, i915_mcr_reg_t reg, u32 value)
 {
-	intel_uncore_write_fw(gt->uncore, reg, value);
+	intel_uncore_write_fw(gt->uncore, mcr_reg_cast(reg), value);
 }
 
 /**
@@ -320,7 +333,7 @@ void intel_gt_mcr_multicast_write_fw(struct intel_gt *gt, i915_reg_t reg, u32 va
  *
  * Returns the old (unmodified) value read.
  */
-u32 intel_gt_mcr_multicast_rmw(struct intel_gt *gt, i915_reg_t reg,
+u32 intel_gt_mcr_multicast_rmw(struct intel_gt *gt, i915_mcr_reg_t reg,
 			       u32 clear, u32 set)
 {
 	u32 val = intel_gt_mcr_read_any(gt, reg);
@@ -345,7 +358,7 @@ u32 intel_gt_mcr_multicast_rmw(struct intel_gt *gt, i915_reg_t reg,
  * for @type steering too.
  */
 static bool reg_needs_read_steering(struct intel_gt *gt,
-				    i915_reg_t reg,
+				    i915_mcr_reg_t reg,
 				    enum intel_steering_type type)
 {
 	const u32 offset = i915_mmio_reg_offset(reg);
@@ -428,7 +441,7 @@ static void get_nonterminated_steering(struct intel_gt *gt,
  * steering.
  */
 void intel_gt_mcr_get_nonterminated_steering(struct intel_gt *gt,
-					     i915_reg_t reg,
+					     i915_mcr_reg_t reg,
 					     u8 *group, u8 *instance)
 {
 	int type;
@@ -457,7 +470,7 @@ void intel_gt_mcr_get_nonterminated_steering(struct intel_gt *gt,
  *
  * Returns the value from a non-terminated instance of @reg.
  */
-u32 intel_gt_mcr_read_any_fw(struct intel_gt *gt, i915_reg_t reg)
+u32 intel_gt_mcr_read_any_fw(struct intel_gt *gt, i915_mcr_reg_t reg)
 {
 	int type;
 	u8 group, instance;
@@ -471,7 +484,7 @@ u32 intel_gt_mcr_read_any_fw(struct intel_gt *gt, i915_reg_t reg)
 		}
 	}
 
-	return intel_uncore_read_fw(gt->uncore, reg);
+	return intel_uncore_read_fw(gt->uncore, mcr_reg_cast(reg));
 }
 
 /**
@@ -484,7 +497,7 @@ u32 intel_gt_mcr_read_any_fw(struct intel_gt *gt, i915_reg_t reg)
  *
  * Returns the value from a non-terminated instance of @reg.
  */
-u32 intel_gt_mcr_read_any(struct intel_gt *gt, i915_reg_t reg)
+u32 intel_gt_mcr_read_any(struct intel_gt *gt, i915_mcr_reg_t reg)
 {
 	int type;
 	u8 group, instance;
@@ -498,7 +511,7 @@ u32 intel_gt_mcr_read_any(struct intel_gt *gt, i915_reg_t reg)
 		}
 	}
 
-	return intel_uncore_read(gt->uncore, reg);
+	return intel_uncore_read(gt->uncore, mcr_reg_cast(reg));
 }
 
 static void report_steering_type(struct drm_printer *p,
@@ -599,7 +612,7 @@ void intel_gt_mcr_get_ss_steering(struct intel_gt *gt, unsigned int dss,
  * Return: 0 if the register matches the desired condition, or -ETIMEDOUT.
  */
 int intel_gt_mcr_wait_for_reg_fw(struct intel_gt *gt,
-				 i915_reg_t reg,
+				 i915_mcr_reg_t reg,
 				 u32 mask,
 				 u32 value,
 				 unsigned int fast_timeout_us,
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_mcr.h b/drivers/gpu/drm/i915/gt/intel_gt_mcr.h
index 548f922cd9fa..3fb0502bff22 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_mcr.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt_mcr.h
@@ -11,24 +11,24 @@
 void intel_gt_mcr_init(struct intel_gt *gt);
 
 u32 intel_gt_mcr_read(struct intel_gt *gt,
-		      i915_reg_t reg,
+		      i915_mcr_reg_t reg,
 		      int group, int instance);
-u32 intel_gt_mcr_read_any_fw(struct intel_gt *gt, i915_reg_t reg);
-u32 intel_gt_mcr_read_any(struct intel_gt *gt, i915_reg_t reg);
+u32 intel_gt_mcr_read_any_fw(struct intel_gt *gt, i915_mcr_reg_t reg);
+u32 intel_gt_mcr_read_any(struct intel_gt *gt, i915_mcr_reg_t reg);
 
 void intel_gt_mcr_unicast_write(struct intel_gt *gt,
-				i915_reg_t reg, u32 value,
+				i915_mcr_reg_t reg, u32 value,
 				int group, int instance);
 void intel_gt_mcr_multicast_write(struct intel_gt *gt,
-				  i915_reg_t reg, u32 value);
+				  i915_mcr_reg_t reg, u32 value);
 void intel_gt_mcr_multicast_write_fw(struct intel_gt *gt,
-				     i915_reg_t reg, u32 value);
+				     i915_mcr_reg_t reg, u32 value);
 
-u32 intel_gt_mcr_multicast_rmw(struct intel_gt *gt, i915_reg_t reg,
+u32 intel_gt_mcr_multicast_rmw(struct intel_gt *gt, i915_mcr_reg_t reg,
 			       u32 clear, u32 set);
 
 void intel_gt_mcr_get_nonterminated_steering(struct intel_gt *gt,
-					     i915_reg_t reg,
+					     i915_mcr_reg_t reg,
 					     u8 *group, u8 *instance);
 
 void intel_gt_mcr_report_steering(struct drm_printer *p, struct intel_gt *gt,
@@ -38,7 +38,7 @@ void intel_gt_mcr_get_ss_steering(struct intel_gt *gt, unsigned int dss,
 				  unsigned int *group, unsigned int *instance);
 
 int intel_gt_mcr_wait_for_reg_fw(struct intel_gt *gt,
-				 i915_reg_t reg,
+				 i915_mcr_reg_t reg,
 				 u32 mask,
 				 u32 value,
 				 unsigned int fast_timeout_us,
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_regs.h b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
index bd2bbacf2386..1116bc3dba51 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_regs.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
@@ -8,7 +8,18 @@
 
 #include "i915_reg_defs.h"
 
-#define MCR_REG(offset)	_MMIO(offset)
+#define MCR_REG(offset)	((const i915_mcr_reg_t){ .reg = (offset) })
+
+/*
+ * The perf control registers are technically multicast registers, but the
+ * driver never needs to read/write them directly; we only use them to build
+ * lists of registers (where they're mixed in with other non-MCR registers)
+ * and then operate on the offset directly.  For now we'll just define them
+ * as non-multicast so we can place them on the same list, but we may want
+ * to try to come up with a better way to handle heterogeneous lists of
+ * registers in the future.
+ */
+#define PERF_REG(offset)			_MMIO(offset)
 
 /* RPM unit config (Gen8+) */
 #define RPM_CONFIG0				_MMIO(0xd00)
@@ -1113,8 +1124,8 @@
 #define   FLOAT_BLEND_OPTIMIZATION_ENABLE	REG_BIT(4)
 #define   ENABLE_PREFETCH_INTO_IC		REG_BIT(3)
 
-#define EU_PERF_CNTL0				MCR_REG(0xe458)
-#define EU_PERF_CNTL4				MCR_REG(0xe45c)
+#define EU_PERF_CNTL0				PERF_REG(0xe458)
+#define EU_PERF_CNTL4				PERF_REG(0xe45c)
 
 #define GEN9_ROW_CHICKEN4			MCR_REG(0xe48c)
 #define   GEN12_DISABLE_GRF_CLEAR		REG_BIT(13)
@@ -1151,16 +1162,16 @@
 #define   STACKID_CTRL				REG_GENMASK(6, 5)
 #define   STACKID_CTRL_512			REG_FIELD_PREP(STACKID_CTRL, 0x2)
 
-#define EU_PERF_CNTL1				MCR_REG(0xe558)
-#define EU_PERF_CNTL5				MCR_REG(0xe55c)
+#define EU_PERF_CNTL1				PERF_REG(0xe558)
+#define EU_PERF_CNTL5				PERF_REG(0xe55c)
 
 #define XEHP_HDC_CHICKEN0			MCR_REG(0xe5f0)
 #define   LSC_L1_FLUSH_CTL_3D_DATAPORT_FLUSH_EVENTS_MASK	REG_GENMASK(13, 11)
 #define ICL_HDC_MODE				MCR_REG(0xe5f4)
 
-#define EU_PERF_CNTL2				MCR_REG(0xe658)
-#define EU_PERF_CNTL6				MCR_REG(0xe65c)
-#define EU_PERF_CNTL3				MCR_REG(0xe758)
+#define EU_PERF_CNTL2				PERF_REG(0xe658)
+#define EU_PERF_CNTL6				PERF_REG(0xe65c)
+#define EU_PERF_CNTL3				PERF_REG(0xe758)
 
 #define LSC_CHICKEN_BIT_0			MCR_REG(0xe7c8)
 #define   DISABLE_D8_D16_COASLESCE		REG_BIT(30)
diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
index 7671994d5b7a..dadb60e6a58f 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
@@ -166,11 +166,11 @@ static void wa_add(struct i915_wa_list *wal, i915_reg_t reg,
 	_wa_add(wal, &wa);
 }
 
-static void wa_mcr_add(struct i915_wa_list *wal, i915_reg_t reg,
+static void wa_mcr_add(struct i915_wa_list *wal, i915_mcr_reg_t reg,
 		       u32 clear, u32 set, u32 read_mask, bool masked_reg)
 {
 	struct i915_wa wa = {
-		.reg  = reg,
+		.mcr_reg = reg,
 		.clr  = clear,
 		.set  = set,
 		.read = read_mask,
@@ -188,7 +188,7 @@ wa_write_clr_set(struct i915_wa_list *wal, i915_reg_t reg, u32 clear, u32 set)
 }
 
 static void
-wa_mcr_write_clr_set(struct i915_wa_list *wal, i915_reg_t reg, u32 clear, u32 set)
+wa_mcr_write_clr_set(struct i915_wa_list *wal, i915_mcr_reg_t reg, u32 clear, u32 set)
 {
 	wa_mcr_add(wal, reg, clear, set, clear, false);
 }
@@ -206,7 +206,7 @@ wa_write_or(struct i915_wa_list *wal, i915_reg_t reg, u32 set)
 }
 
 static void
-wa_mcr_write_or(struct i915_wa_list *wal, i915_reg_t reg, u32 set)
+wa_mcr_write_or(struct i915_wa_list *wal, i915_mcr_reg_t reg, u32 set)
 {
 	wa_mcr_write_clr_set(wal, reg, set, set);
 }
@@ -218,7 +218,7 @@ wa_write_clr(struct i915_wa_list *wal, i915_reg_t reg, u32 clr)
 }
 
 static void
-wa_mcr_write_clr(struct i915_wa_list *wal, i915_reg_t reg, u32 clr)
+wa_mcr_write_clr(struct i915_wa_list *wal, i915_mcr_reg_t reg, u32 clr)
 {
 	wa_mcr_write_clr_set(wal, reg, clr, 0);
 }
@@ -241,7 +241,7 @@ wa_masked_en(struct i915_wa_list *wal, i915_reg_t reg, u32 val)
 }
 
 static void
-wa_mcr_masked_en(struct i915_wa_list *wal, i915_reg_t reg, u32 val)
+wa_mcr_masked_en(struct i915_wa_list *wal, i915_mcr_reg_t reg, u32 val)
 {
 	wa_mcr_add(wal, reg, 0, _MASKED_BIT_ENABLE(val), val, true);
 }
@@ -253,7 +253,7 @@ wa_masked_dis(struct i915_wa_list *wal, i915_reg_t reg, u32 val)
 }
 
 static void
-wa_mcr_masked_dis(struct i915_wa_list *wal, i915_reg_t reg, u32 val)
+wa_mcr_masked_dis(struct i915_wa_list *wal, i915_mcr_reg_t reg, u32 val)
 {
 	wa_mcr_add(wal, reg, 0, _MASKED_BIT_DISABLE(val), val, true);
 }
@@ -266,7 +266,7 @@ wa_masked_field_set(struct i915_wa_list *wal, i915_reg_t reg,
 }
 
 static void
-wa_mcr_masked_field_set(struct i915_wa_list *wal, i915_reg_t reg,
+wa_mcr_masked_field_set(struct i915_wa_list *wal, i915_mcr_reg_t reg,
 			u32 mask, u32 val)
 {
 	wa_mcr_add(wal, reg, 0, _MASKED_FIELD(mask, val), mask, true);
@@ -1692,19 +1692,19 @@ wa_list_apply(struct intel_gt *gt, const struct i915_wa_list *wal)
 		/* open-coded rmw due to steering */
 		if (wa->clr)
 			old = wa->is_mcr ?
-				intel_gt_mcr_read_any_fw(gt, wa->reg) :
+				intel_gt_mcr_read_any_fw(gt, wa->mcr_reg) :
 				intel_uncore_read_fw(uncore, wa->reg);
 		val = (old & ~wa->clr) | wa->set;
 		if (val != old || !wa->clr) {
 			if (wa->is_mcr)
-				intel_gt_mcr_multicast_write_fw(gt, wa->reg, val);
+				intel_gt_mcr_multicast_write_fw(gt, wa->mcr_reg, val);
 			else
 				intel_uncore_write_fw(uncore, wa->reg, val);
 		}
 
 		if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) {
 			u32 val = wa->is_mcr ?
-				intel_gt_mcr_read_any_fw(gt, wa->reg) :
+				intel_gt_mcr_read_any_fw(gt, wa->mcr_reg) :
 				intel_uncore_read_fw(uncore, wa->reg);
 
 			wa_verify(wa, val, wal->name, "application");
@@ -1738,7 +1738,7 @@ static bool wa_list_verify(struct intel_gt *gt,
 
 	for (i = 0, wa = wal->list; i < wal->count; i++, wa++)
 		ok &= wa_verify(wa, wa->is_mcr ?
-				intel_gt_mcr_read_any_fw(gt, wa->reg) :
+				intel_gt_mcr_read_any_fw(gt, wa->mcr_reg) :
 				intel_uncore_read_fw(uncore, wa->reg),
 				wal->name, from);
 
@@ -1786,10 +1786,10 @@ whitelist_reg_ext(struct i915_wa_list *wal, i915_reg_t reg, u32 flags)
 }
 
 static void
-whitelist_mcr_reg_ext(struct i915_wa_list *wal, i915_reg_t reg, u32 flags)
+whitelist_mcr_reg_ext(struct i915_wa_list *wal, i915_mcr_reg_t reg, u32 flags)
 {
 	struct i915_wa wa = {
-		.reg = reg,
+		.mcr_reg = reg,
 		.is_mcr = 1,
 	};
 
@@ -1799,7 +1799,7 @@ whitelist_mcr_reg_ext(struct i915_wa_list *wal, i915_reg_t reg, u32 flags)
 	if (GEM_DEBUG_WARN_ON(!is_nonpriv_flags_valid(flags)))
 		return;
 
-	wa.reg.reg |= flags;
+	wa.mcr_reg.reg |= flags;
 	_wa_add(wal, &wa);
 }
 
@@ -1810,7 +1810,7 @@ whitelist_reg(struct i915_wa_list *wal, i915_reg_t reg)
 }
 
 static void
-whitelist_mcr_reg(struct i915_wa_list *wal, i915_reg_t reg)
+whitelist_mcr_reg(struct i915_wa_list *wal, i915_mcr_reg_t reg)
 {
 	whitelist_mcr_reg_ext(wal, reg, RING_FORCE_TO_NONPRIV_ACCESS_RW);
 }
diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds_types.h b/drivers/gpu/drm/i915/gt/intel_workarounds_types.h
index f05b37e56fa9..7c8b01d00043 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds_types.h
@@ -11,7 +11,10 @@
 #include "i915_reg_defs.h"
 
 struct i915_wa {
-	i915_reg_t	reg;
+	union {
+		i915_reg_t	reg;
+		i915_mcr_reg_t	mcr_reg;
+	};
 	u32		clr;
 	u32		set;
 	u32		read;
diff --git a/drivers/gpu/drm/i915/gt/selftest_workarounds.c b/drivers/gpu/drm/i915/gt/selftest_workarounds.c
index 67a9aab801dd..21b1edc052f8 100644
--- a/drivers/gpu/drm/i915/gt/selftest_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/selftest_workarounds.c
@@ -991,7 +991,7 @@ static bool pardon_reg(struct drm_i915_private *i915, i915_reg_t reg)
 	/* Alas, we must pardon some whitelists. Mistakes already made */
 	static const struct regmask pardon[] = {
 		{ GEN9_CTX_PREEMPT_REG, 9 },
-		{ GEN8_L3SQCREG4, 9 },
+		{ _MMIO(0xb118), 9 }, /* GEN8_L3SQCREG4 */
 	};
 
 	return find_reg(i915, reg, pardon, ARRAY_SIZE(pardon));
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
index de923fb82301..34ef4f36e660 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
@@ -328,7 +328,7 @@ static long __must_check guc_mmio_reg_add(struct intel_gt *gt,
 
 static long __must_check guc_mcr_reg_add(struct intel_gt *gt,
 					 struct temp_regset *regset,
-					 i915_reg_t reg, u32 flags)
+					 i915_mcr_reg_t reg, u32 flags)
 {
 	u8 group, inst;
 
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_capture.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_capture.c
index 9495a7928bc8..d5c03e7a7843 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_capture.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_capture.c
@@ -240,7 +240,7 @@ static void guc_capture_free_extlists(struct __guc_mmio_reg_descr_group *reglist
 
 struct __ext_steer_reg {
 	const char *name;
-	i915_reg_t reg;
+	i915_mcr_reg_t reg;
 };
 
 static const struct __ext_steer_reg xe_extregs[] = {
@@ -252,7 +252,7 @@ static void __fill_ext_reg(struct __guc_mmio_reg_descr *ext,
 			   const struct __ext_steer_reg *extlist,
 			   int slice_id, int subslice_id)
 {
-	ext->reg = extlist->reg;
+	ext->reg = _MMIO(i915_mmio_reg_offset(extlist->reg));
 	ext->flags = FIELD_PREP(GUC_REGSET_STEERING_GROUP, slice_id);
 	ext->flags |= FIELD_PREP(GUC_REGSET_STEERING_INSTANCE, subslice_id);
 	ext->regname = extlist->name;
diff --git a/drivers/gpu/drm/i915/gvt/handlers.c b/drivers/gpu/drm/i915/gvt/handlers.c
index 683f88f5d669..41ab6c99e3a0 100644
--- a/drivers/gpu/drm/i915/gvt/handlers.c
+++ b/drivers/gpu/drm/i915/gvt/handlers.c
@@ -734,7 +734,7 @@ static i915_reg_t force_nonpriv_white_list[] = {
 	_MMIO(0x770c),
 	_MMIO(0x83a8),
 	_MMIO(0xb110),
-	GEN8_L3SQCREG4,//_MMIO(0xb118)
+	_MMIO(0xb118),
 	_MMIO(0xe100),
 	_MMIO(0xe18c),
 	_MMIO(0xe48c),
diff --git a/drivers/gpu/drm/i915/gvt/mmio_context.c b/drivers/gpu/drm/i915/gvt/mmio_context.c
index 485ff6c8e558..5197e15cb78e 100644
--- a/drivers/gpu/drm/i915/gvt/mmio_context.c
+++ b/drivers/gpu/drm/i915/gvt/mmio_context.c
@@ -106,15 +106,15 @@ static struct engine_mmio gen9_engine_mmio_list[] __cacheline_aligned = {
 	{RCS0, GEN8_CS_CHICKEN1, 0xffff, true}, /* 0x2580 */
 	{RCS0, COMMON_SLICE_CHICKEN2, 0xffff, true}, /* 0x7014 */
 	{RCS0, GEN9_CS_DEBUG_MODE1, 0xffff, false}, /* 0x20ec */
-	{RCS0, GEN8_L3SQCREG4, 0, false}, /* 0xb118 */
-	{RCS0, GEN9_SCRATCH1, 0, false}, /* 0xb11c */
+	{RCS0, _MMIO(0xb118), 0, false}, /* GEN8_L3SQCREG4 */
+	{RCS0, _MMIO(0xb11c), 0, false}, /* GEN9_SCRATCH1 */
 	{RCS0, GEN9_SCRATCH_LNCF1, 0, false}, /* 0xb008 */
 	{RCS0, GEN7_HALF_SLICE_CHICKEN1, 0xffff, true}, /* 0xe100 */
-	{RCS0, HALF_SLICE_CHICKEN2, 0xffff, true}, /* 0xe180 */
-	{RCS0, GEN8_HALF_SLICE_CHICKEN3, 0xffff, true}, /* 0xe184 */
-	{RCS0, GEN9_HALF_SLICE_CHICKEN5, 0xffff, true}, /* 0xe188 */
-	{RCS0, GEN9_HALF_SLICE_CHICKEN7, 0xffff, true}, /* 0xe194 */
-	{RCS0, GEN8_ROW_CHICKEN, 0xffff, true}, /* 0xe4f0 */
+	{RCS0, _MMIO(0xe180), 0xffff, true}, /* HALF_SLICE_CHICKEN2 */
+	{RCS0, _MMIO(0xe184), 0xffff, true}, /* GEN8_HALF_SLICE_CHICKEN3 */
+	{RCS0, _MMIO(0xe188), 0xffff, true}, /* GEN9_HALF_SLICE_CHICKEN5 */
+	{RCS0, _MMIO(0xe194), 0xffff, true}, /* GEN9_HALF_SLICE_CHICKEN7 */
+	{RCS0, _MMIO(0xe4f0), 0xffff, true}, /* GEN8_ROW_CHICKEN */
 	{RCS0, TRVATTL3PTRDW(0), 0, true}, /* 0x4de0 */
 	{RCS0, TRVATTL3PTRDW(1), 0, true}, /* 0x4de4 */
 	{RCS0, TRNULLDETCT, 0, true}, /* 0x4de8 */
diff --git a/drivers/gpu/drm/i915/i915_reg_defs.h b/drivers/gpu/drm/i915/i915_reg_defs.h
index 8f486f77609f..f1859046a9c4 100644
--- a/drivers/gpu/drm/i915/i915_reg_defs.h
+++ b/drivers/gpu/drm/i915/i915_reg_defs.h
@@ -104,22 +104,21 @@ typedef struct {
 
 #define _MMIO(r) ((const i915_reg_t){ .reg = (r) })
 
-#define INVALID_MMIO_REG _MMIO(0)
-
-static __always_inline u32 i915_mmio_reg_offset(i915_reg_t reg)
-{
-	return reg.reg;
-}
+typedef struct {
+	u32 reg;
+} i915_mcr_reg_t;
 
-static inline bool i915_mmio_reg_equal(i915_reg_t a, i915_reg_t b)
-{
-	return i915_mmio_reg_offset(a) == i915_mmio_reg_offset(b);
-}
+#define INVALID_MMIO_REG _MMIO(0)
 
-static inline bool i915_mmio_reg_valid(i915_reg_t reg)
-{
-	return !i915_mmio_reg_equal(reg, INVALID_MMIO_REG);
-}
+/*
+ * These macros can be used on either i915_reg_t or i915_mcr_reg_t since they're
+ * simply operations on the register's offset and don't care about the MCR vs
+ * non-MCR nature of the register.
+ */
+#define i915_mmio_reg_offset(r) \
+	_Generic((r), i915_reg_t: (r).reg, i915_mcr_reg_t: (r).reg)
+#define i915_mmio_reg_equal(a, b) (i915_mmio_reg_offset(a) == i915_mmio_reg_offset(b))
+#define i915_mmio_reg_valid(r) (!i915_mmio_reg_equal(r, INVALID_MMIO_REG))
 
 #define VLV_DISPLAY_BASE		0x180000