[PATCH Review 1/1] drm/amdgpu: adjust register address calculation

[Stanley.Yang]

the UMC_STATUS register is not liner, adjust offset
calculation formula to get correct address

Change-Id: Ic8926078301848330babf289c4238dc8cbcf313d
Signed-off-by: Stanley.Yang <Stanley.Yang at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/umc_v6_7.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/umc_v6_7.c b/drivers/gpu/drm/amd/amdgpu/umc_v6_7.c
index e613511e07e1..87e4ef18e151 100644
--- a/drivers/gpu/drm/amd/amdgpu/umc_v6_7.c
+++ b/drivers/gpu/drm/amd/amdgpu/umc_v6_7.c
@@ -47,6 +47,13 @@ static inline uint32_t get_umc_v6_7_reg_offset(struct amdgpu_device *adev,
 					      uint32_t umc_inst,
 					      uint32_t ch_inst)
 {
+	uint32_t index = umc_inst * adev->umc.channel_inst_num + ch_inst;
+
+	/* adjust umc and channel index offset,
+	 * the register address is not linear on each umc instace */
+	umc_inst = index / 4;
+	ch_inst = index % 4;
+
 	return adev->umc.channel_offs * ch_inst + UMC_V6_7_INST_DIST * umc_inst;
 }
 
-- 
2.17.1