From 11ed50ec2a316928c2bacc1149bded86c6a96068 Mon Sep 17 00:00:00 2001 From: Ben Gamari Date: Mon, 14 Sep 2009 17:48:45 -0400 Subject: drm/i915: Implement GPU reset on i965 This patch puts in place the machinery to attempt to reset the GPU. This will be used when attempting to recover from a GPU hang. Signed-off-by: Owain G. Ainsworth Signed-off-by: Ben Gamari Signed-off-by: Jesse Barnes --- drivers/gpu/drm/i915/i915_drv.c | 124 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) (limited to 'drivers/gpu/drm/i915/i915_drv.c') diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index dbe568c9327..435082e4073 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -127,6 +127,130 @@ static int i915_resume(struct drm_device *dev) return ret; } +/** + * i965_reset - reset chip after a hang + * @dev: drm device to reset + * @flags: reset domains + * + * Reset the chip. Useful if a hang is detected. Returns zero on successful + * reset or otherwise an error code. + * + * Procedure is fairly simple: + * - reset the chip using the reset reg + * - re-init context state + * - re-init hardware status page + * - re-init ring buffer + * - re-init interrupt state + * - re-init display + */ +int i965_reset(struct drm_device *dev, u8 flags) +{ + drm_i915_private_t *dev_priv = dev->dev_private; + unsigned long timeout; + u8 gdrst; + /* + * We really should only reset the display subsystem if we actually + * need to + */ + bool need_display = true; + + mutex_lock(&dev->struct_mutex); + + /* + * Clear request list + */ + i915_gem_retire_requests(dev); + + if (need_display) + i915_save_display(dev); + + if (IS_I965G(dev) || IS_G4X(dev)) { + /* + * Set the domains we want to reset, then the reset bit (bit 0). + * Clear the reset bit after a while and wait for hardware status + * bit (bit 1) to be set + */ + pci_read_config_byte(dev->pdev, GDRST, &gdrst); + pci_write_config_byte(dev->pdev, GDRST, gdrst | flags | ((flags == GDRST_FULL) ? 0x1 : 0x0)); + udelay(50); + pci_write_config_byte(dev->pdev, GDRST, gdrst & 0xfe); + + /* ...we don't want to loop forever though, 500ms should be plenty */ + timeout = jiffies + msecs_to_jiffies(500); + do { + udelay(100); + pci_read_config_byte(dev->pdev, GDRST, &gdrst); + } while ((gdrst & 0x1) && time_after(timeout, jiffies)); + + if (gdrst & 0x1) { + WARN(true, "i915: Failed to reset chip\n"); + mutex_unlock(&dev->struct_mutex); + return -EIO; + } + } else { + DRM_ERROR("Error occurred. Don't know how to reset this chip.\n"); + return -ENODEV; + } + + /* Ok, now get things going again... */ + + /* + * Everything depends on having the GTT running, so we need to start + * there. Fortunately we don't need to do this unless we reset the + * chip at a PCI level. + * + * Next we need to restore the context, but we don't use those + * yet either... + * + * Ring buffer needs to be re-initialized in the KMS case, or if X + * was running at the time of the reset (i.e. we weren't VT + * switched away). + */ + if (drm_core_check_feature(dev, DRIVER_MODESET) || + !dev_priv->mm.suspended) { + drm_i915_ring_buffer_t *ring = &dev_priv->ring; + struct drm_gem_object *obj = ring->ring_obj; + struct drm_i915_gem_object *obj_priv = obj->driver_private; + dev_priv->mm.suspended = 0; + + /* Stop the ring if it's running. */ + I915_WRITE(PRB0_CTL, 0); + I915_WRITE(PRB0_TAIL, 0); + I915_WRITE(PRB0_HEAD, 0); + + /* Initialize the ring. */ + I915_WRITE(PRB0_START, obj_priv->gtt_offset); + I915_WRITE(PRB0_CTL, + ((obj->size - 4096) & RING_NR_PAGES) | + RING_NO_REPORT | + RING_VALID); + if (!drm_core_check_feature(dev, DRIVER_MODESET)) + i915_kernel_lost_context(dev); + else { + ring->head = I915_READ(PRB0_HEAD) & HEAD_ADDR; + ring->tail = I915_READ(PRB0_TAIL) & TAIL_ADDR; + ring->space = ring->head - (ring->tail + 8); + if (ring->space < 0) + ring->space += ring->Size; + } + + mutex_unlock(&dev->struct_mutex); + drm_irq_uninstall(dev); + drm_irq_install(dev); + mutex_lock(&dev->struct_mutex); + } + + /* + * Display needs restore too... + */ + if (need_display) + i915_restore_display(dev); + + mutex_unlock(&dev->struct_mutex); + return 0; +} + + static int __devinit i915_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent) { -- cgit v1.2.3