return true;
 }
 
-//xxx: not implemented
+static void si_set_clk_bypass_mode(struct amdgpu_device *adev)
+{
+       u32 tmp, i;
+
+       tmp = RREG32(CG_SPLL_FUNC_CNTL);
+       tmp |= SPLL_BYPASS_EN;
+       WREG32(CG_SPLL_FUNC_CNTL, tmp);
+
+       tmp = RREG32(CG_SPLL_FUNC_CNTL_2);
+       tmp |= SPLL_CTLREQ_CHG;
+       WREG32(CG_SPLL_FUNC_CNTL_2, tmp);
+
+       for (i = 0; i < adev->usec_timeout; i++) {
+               if (RREG32(SPLL_STATUS) & SPLL_CHG_STATUS)
+                       break;
+               udelay(1);
+       }
+
+       tmp = RREG32(CG_SPLL_FUNC_CNTL_2);
+       tmp &= ~(SPLL_CTLREQ_CHG | SCLK_MUX_UPDATE);
+       WREG32(CG_SPLL_FUNC_CNTL_2, tmp);
+
+       tmp = RREG32(MPLL_CNTL_MODE);
+       tmp &= ~MPLL_MCLK_SEL;
+       WREG32(MPLL_CNTL_MODE, tmp);
+}
+
+static void si_spll_powerdown(struct amdgpu_device *adev)
+{
+       u32 tmp;
+
+       tmp = RREG32(SPLL_CNTL_MODE);
+       tmp |= SPLL_SW_DIR_CONTROL;
+       WREG32(SPLL_CNTL_MODE, tmp);
+
+       tmp = RREG32(CG_SPLL_FUNC_CNTL);
+       tmp |= SPLL_RESET;
+       WREG32(CG_SPLL_FUNC_CNTL, tmp);
+
+       tmp = RREG32(CG_SPLL_FUNC_CNTL);
+       tmp |= SPLL_SLEEP;
+       WREG32(CG_SPLL_FUNC_CNTL, tmp);
+
+       tmp = RREG32(SPLL_CNTL_MODE);
+       tmp &= ~SPLL_SW_DIR_CONTROL;
+       WREG32(SPLL_CNTL_MODE, tmp);
+}
+
+static int si_gpu_pci_config_reset(struct amdgpu_device *adev)
+{
+       u32 i;
+       int r = -EINVAL;
+
+       dev_info(adev->dev, "GPU pci config reset\n");
+
+       /* set mclk/sclk to bypass */
+       si_set_clk_bypass_mode(adev);
+       /* powerdown spll */
+       si_spll_powerdown(adev);
+       /* disable BM */
+       pci_clear_master(adev->pdev);
+       /* reset */
+       amdgpu_device_pci_config_reset(adev);
+
+       udelay(100);
+
+       /* wait for asic to come out of reset */
+       for (i = 0; i < adev->usec_timeout; i++) {
+               if (RREG32(mmCONFIG_MEMSIZE) != 0xffffffff) {
+                       /* enable BM */
+                       pci_set_master(adev->pdev);
+                       adev->has_hw_reset = true;
+                       r = 0;
+                       break;
+               }
+               udelay(1);
+       }
+
+       return r;
+}
+
 static int si_asic_reset(struct amdgpu_device *adev)
 {
-       return 0;
+       int r;
+
+       amdgpu_atombios_scratch_regs_engine_hung(adev, true);
+
+       r = si_gpu_pci_config_reset(adev);
+
+       amdgpu_atombios_scratch_regs_engine_hung(adev, false);
+
+       return r;
 }
 
 static bool si_asic_supports_baco(struct amdgpu_device *adev)