From 40633219a0ff4953601c7b2326f8faabc0171fd9 Mon Sep 17 00:00:00 2001 From: Mika Kuoppala Date: Tue, 4 Dec 2012 15:12:00 +0200 Subject: [PATCH] drm/i915: Add debugfs entry to read/write next_seqno This is needed for testing seqno wrapping. Be careful to not bump next_seqno more than 0x7FFFFFFF at a time (between some handled requests) as i915_seqno_passed() can't handle bigger difference in between. v2: Address review comments from Chris Wilson. Signed-off-by: Mika Kuoppala Acked-by: Chris Wilson [danvet: Squash in fixup to properly remove the debugfs file on driver unload again.] Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_debugfs.c | 88 +++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index ce60506b574b..602058fb5e25 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -843,6 +843,86 @@ static const struct file_operations i915_error_state_fops = { .release = i915_error_state_release, }; +static ssize_t +i915_next_seqno_read(struct file *filp, + char __user *ubuf, + size_t max, + loff_t *ppos) +{ + struct drm_device *dev = filp->private_data; + drm_i915_private_t *dev_priv = dev->dev_private; + char buf[80]; + int len; + int ret; + + ret = mutex_lock_interruptible(&dev->struct_mutex); + if (ret) + return ret; + + len = snprintf(buf, sizeof(buf), + "next_seqno : 0x%x\n", + dev_priv->next_seqno); + + mutex_unlock(&dev->struct_mutex); + + if (len > sizeof(buf)) + len = sizeof(buf); + + return simple_read_from_buffer(ubuf, max, ppos, buf, len); +} + +static ssize_t +i915_next_seqno_write(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + struct drm_device *dev = filp->private_data; + drm_i915_private_t *dev_priv = dev->dev_private; + char buf[20]; + u32 val = 1; + int ret; + + if (cnt > 0) { + if (cnt > sizeof(buf) - 1) + return -EINVAL; + + if (copy_from_user(buf, ubuf, cnt)) + return -EFAULT; + buf[cnt] = 0; + + ret = kstrtouint(buf, 0, &val); + if (ret < 0) + return ret; + } + + if (val == 0) + return -EINVAL; + + ret = mutex_lock_interruptible(&dev->struct_mutex); + if (ret) + return ret; + + if (i915_seqno_passed(val, dev_priv->next_seqno)) { + dev_priv->next_seqno = val; + DRM_DEBUG_DRIVER("Advancing seqno to %u\n", val); + } else { + ret = -EINVAL; + } + + mutex_unlock(&dev->struct_mutex); + + return ret ?: cnt; +} + +static const struct file_operations i915_next_seqno_fops = { + .owner = THIS_MODULE, + .open = simple_open, + .read = i915_next_seqno_read, + .write = i915_next_seqno_write, + .llseek = default_llseek, +}; + static int i915_rstdby_delays(struct seq_file *m, void *unused) { struct drm_info_node *node = (struct drm_info_node *) m->private; @@ -2107,6 +2187,12 @@ int i915_debugfs_init(struct drm_minor *minor) if (ret) return ret; + ret = i915_debugfs_create(minor->debugfs_root, minor, + "i915_next_seqno", + &i915_next_seqno_fops); + if (ret) + return ret; + return drm_debugfs_create_files(i915_debugfs_list, I915_DEBUGFS_ENTRIES, minor->debugfs_root, minor); @@ -2130,6 +2216,8 @@ void i915_debugfs_cleanup(struct drm_minor *minor) 1, minor); drm_debugfs_remove_files((struct drm_info_list *) &i915_error_state_fops, 1, minor); + drm_debugfs_remove_files((struct drm_info_list *) &i915_next_seqno_fops, + 1, minor); } #endif /* CONFIG_DEBUG_FS */ -- 2.20.1