drm/radeon: add indirect register accessors for SMC registers

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/evergreen_reg.h

@@ -24,6 +24,10 @@
 #ifndef __EVERGREEN_REG_H__
 #define __EVERGREEN_REG_H__
 
+/* trinity */
+#define TN_SMC_IND_INDEX_0                              0x200
+#define TN_SMC_IND_DATA_0                               0x204
+
 /* evergreen */
 #define EVERGREEN_VGA_MEMORY_BASE_ADDRESS               0x310
 #define EVERGREEN_VGA_MEMORY_BASE_ADDRESS_HIGH          0x324

drivers/gpu/drm/radeon/radeon.h

@@ -1806,6 +1806,8 @@ void r100_io_wreg(struct radeon_device *rdev, u32 reg, u32 v);
 #define WREG32_PCIE(reg, v) rv370_pcie_wreg(rdev, (reg), (v))
 #define RREG32_PCIE_PORT(reg) rdev->pciep_rreg(rdev, (reg))
 #define WREG32_PCIE_PORT(reg, v) rdev->pciep_wreg(rdev, (reg), (v))
+#define RREG32_SMC(reg) tn_smc_rreg(rdev, (reg))
+#define WREG32_SMC(reg, v) tn_smc_wreg(rdev, (reg), (v))
 #define WREG32_P(reg, val, mask)				\
 	do {							\
 		uint32_t tmp_ = RREG32(reg);			\
@@ -1844,6 +1846,21 @@ static inline void rv370_pcie_wreg(struct radeon_device *rdev, uint32_t reg, uin
 	WREG32(RADEON_PCIE_DATA, (v));
 }
 
+static inline u32 tn_smc_rreg(struct radeon_device *rdev, u32 reg)
+{
+	u32 r;
+
+	WREG32(TN_SMC_IND_INDEX_0, (reg));
+	r = RREG32(TN_SMC_IND_DATA_0);
+	return r;
+}
+
+static inline void tn_smc_wreg(struct radeon_device *rdev, u32 reg, u32 v)
+{
+	WREG32(TN_SMC_IND_INDEX_0, (reg));
+	WREG32(TN_SMC_IND_DATA_0, (v));
+}
+
 void r100_pll_errata_after_index(struct radeon_device *rdev);