drm/radeon/kms: simplify & improve GPU reset V2

This simplify and improve GPU reset for R1XX-R6XX hw, it's
not 100% reliable here are result:
- R1XX/R2XX works bunch of time in a row, sometimes it
  seems it can work indifinitly
- R3XX/R3XX the most unreliable one, sometimes you will be
  able to reset few times, sometimes not even once
- R5XX more reliable than previous hw, seems to work most
  of the times but once in a while it fails for no obvious
  reasons (same status than previous reset just no same
  happy ending)
- R6XX/R7XX are lot more reliable with this patch, still
  it seems that it can fail after a bunch (reset every
  2sec for 3hour bring down the GPU & computer)

This have been tested on various hw, for some odd reasons
i wasn't able to lockup RS480/RS690 (while they use to
love locking up).

Note that on R1XX-R5XX the cursor will disapear after
lockup haven't checked why, switch to console and back
to X will restore cursor.

Next step is to record the bogus command that leaded to
the lockup.

V2 Fix r6xx resume path to avoid reinitializing blit
module, use the gpu_lockup boolean to avoid entering
inifinite waiting loop on fence while reiniting the GPU

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 72 insertions, 1 deletions

diff --git a/drivers/gpu/drm/radeon/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index c1be20afd42..a16d9d79f36 100644
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -147,6 +147,78 @@ void rs600_hpd_fini(struct radeon_device *rdev)
 	}
 }
 
+void rs600_bm_disable(struct radeon_device *rdev)
+{
+	u32 tmp;
+
+	/* disable bus mastering */
+	pci_read_config_word(rdev->pdev, 0x4, (u16*)&tmp);
+	pci_write_config_word(rdev->pdev, 0x4, tmp & 0xFFFB);
+	mdelay(1);
+}
+
+int rs600_asic_reset(struct radeon_device *rdev)
+{
+	u32 status, tmp;
+
+	struct rv515_mc_save save;
+
+	/* Stops all mc clients */
+	rv515_mc_stop(rdev, &save);
+	status = RREG32(R_000E40_RBBM_STATUS);
+	if (!G_000E40_GUI_ACTIVE(status)) {
+		return 0;
+	}
+	status = RREG32(R_000E40_RBBM_STATUS);
+	dev_info(rdev->dev, "(%s:%d) RBBM_STATUS=0x%08X\n", __func__, __LINE__, status);
+	/* stop CP */
+	WREG32(RADEON_CP_CSQ_CNTL, 0);
+	tmp = RREG32(RADEON_CP_RB_CNTL);
+	WREG32(RADEON_CP_RB_CNTL, tmp | RADEON_RB_RPTR_WR_ENA);
+	WREG32(RADEON_CP_RB_RPTR_WR, 0);
+	WREG32(RADEON_CP_RB_WPTR, 0);
+	WREG32(RADEON_CP_RB_CNTL, tmp);
+	pci_save_state(rdev->pdev);
+	/* disable bus mastering */
+	rs600_bm_disable(rdev);
+	/* reset GA+VAP */
+	WREG32(R_0000F0_RBBM_SOFT_RESET, S_0000F0_SOFT_RESET_VAP(1) |
+					S_0000F0_SOFT_RESET_GA(1));
+	RREG32(R_0000F0_RBBM_SOFT_RESET);
+	mdelay(500);
+	WREG32(R_0000F0_RBBM_SOFT_RESET, 0);
+	mdelay(1);
+	status = RREG32(R_000E40_RBBM_STATUS);
+	dev_info(rdev->dev, "(%s:%d) RBBM_STATUS=0x%08X\n", __func__, __LINE__, status);
+	/* reset CP */
+	WREG32(R_0000F0_RBBM_SOFT_RESET, S_0000F0_SOFT_RESET_CP(1));
+	RREG32(R_0000F0_RBBM_SOFT_RESET);
+	mdelay(500);
+	WREG32(R_0000F0_RBBM_SOFT_RESET, 0);
+	mdelay(1);
+	status = RREG32(R_000E40_RBBM_STATUS);
+	dev_info(rdev->dev, "(%s:%d) RBBM_STATUS=0x%08X\n", __func__, __LINE__, status);
+	/* reset MC */
+	WREG32(R_0000F0_RBBM_SOFT_RESET, S_0000F0_SOFT_RESET_MC(1));
+	RREG32(R_0000F0_RBBM_SOFT_RESET);
+	mdelay(500);
+	WREG32(R_0000F0_RBBM_SOFT_RESET, 0);
+	mdelay(1);
+	status = RREG32(R_000E40_RBBM_STATUS);
+	dev_info(rdev->dev, "(%s:%d) RBBM_STATUS=0x%08X\n", __func__, __LINE__, status);
+	/* restore PCI & busmastering */
+	pci_restore_state(rdev->pdev);
+	/* Check if GPU is idle */
+	if (G_000E40_GA_BUSY(status) || G_000E40_VAP_BUSY(status)) {
+		dev_err(rdev->dev, "failed to reset GPU\n");
+		rdev->gpu_lockup = true;
+		return -1;
+	}
+	rv515_mc_resume(rdev, &save);
+	dev_info(rdev->dev, "GPU reset succeed\n");
+	return 0;
+}
+
 /*
  * GART.
  */
@@ -454,7 +526,6 @@ int rs600_mc_wait_for_idle(struct radeon_device *rdev)
 
 void rs600_gpu_init(struct radeon_device *rdev)
 {
-	r100_hdp_reset(rdev);
 	r420_pipes_init(rdev);
 	/* Wait for mc idle */
 	if (rs600_mc_wait_for_idle(rdev))