drm/amdgpu: Add initial VI support

[Dan Carpenter]

Hello Alex Deucher,

The patch aaa36a976bbb: "drm/amdgpu: Add initial VI support" from Apr
20, 2015, leads to the following static checker warning:

	drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c:260 gmc_v8_0_mc_load_microcode()
	warn: we tested 'running' before and it was 'false'

drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
   257          running = REG_GET_FIELD(RREG32(mmMC_SEQ_SUP_CNTL), MC_SEQ_SUP_CNTL, RUN);
   258  
   259          if (running == 0) {
                    ^^^^^^^^^^^^
   260                  if (running) {
                            ^^^^^^^
Never true.

   261                          blackout = RREG32(mmMC_SHARED_BLACKOUT_CNTL);
   262                          WREG32(mmMC_SHARED_BLACKOUT_CNTL, blackout | 1);
   263                  }
   264  
   265                  /* reset the engine and set to writable */
   266                  WREG32(mmMC_SEQ_SUP_CNTL, 0x00000008);
   267                  WREG32(mmMC_SEQ_SUP_CNTL, 0x00000010);
   268  
   269                  /* load mc io regs */
   270                  for (i = 0; i < regs_size; i++) {
   271                          WREG32(mmMC_SEQ_IO_DEBUG_INDEX, le32_to_cpup(io_mc_regs++));
   272                          WREG32(mmMC_SEQ_IO_DEBUG_DATA, le32_to_cpup(io_mc_regs++));
   273                  }
   274                  /* load the MC ucode */
   275                  for (i = 0; i < ucode_size; i++)
   276                          WREG32(mmMC_SEQ_SUP_PGM, le32_to_cpup(fw_data++));
   277  
   278                  /* put the engine back into the active state */
   279                  WREG32(mmMC_SEQ_SUP_CNTL, 0x00000008);
   280                  WREG32(mmMC_SEQ_SUP_CNTL, 0x00000004);
   281                  WREG32(mmMC_SEQ_SUP_CNTL, 0x00000001);
   282  
   283                  /* wait for training to complete */
   284                  for (i = 0; i < adev->usec_timeout; i++) {
   285                          if (REG_GET_FIELD(RREG32(mmMC_SEQ_TRAIN_WAKEUP_CNTL),
   286                                            MC_SEQ_TRAIN_WAKEUP_CNTL, TRAIN_DONE_D0))
   287                                  break;
   288                          udelay(1);
   289                  }
   290                  for (i = 0; i < adev->usec_timeout; i++) {
   291                          if (REG_GET_FIELD(RREG32(mmMC_SEQ_TRAIN_WAKEUP_CNTL),
   292                                            MC_SEQ_TRAIN_WAKEUP_CNTL, TRAIN_DONE_D1))
   293                                  break;
   294                          udelay(1);
   295                  }
   296  
   297                  if (running)
                            ^^^^^^^
Same.

   298                          WREG32(mmMC_SHARED_BLACKOUT_CNTL, blackout);
   299          }
   300  

regards,
dan carpenter