[PATCH 39/43] drm/i915/bdw: Print context state in debugfs

Thomas Daniel
2014-08-07T12:24:28Z

From: Ben Widawsky <ben@bwidawsk.net>

This has turned out to be really handy in debug so far.

Update:
Since writing this patch, I've gotten similar code upstream for error
state. I've used it quite a bit in debugfs however, and I'd like to keep
it here at least until preemption is working.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>

This patch was accidentally dropped in the first Execlists version, and
it has been very useful indeed. Put it back again, but as a standalone
debugfs file.

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>

v2: Take the device struct_mutex rather than mode_config mutex for
atomic state capture.

Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
---
drivers/gpu/drm/i915/i915_debugfs.c | 52 +++++++++++++++++++++++++++++++++++
1 file changed, 52 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index aca5ff1..a3c958c 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1695,6 +1695,57 @@ static int i915_context_status(struct seq_file *m, void *unused)
return 0;
}

+static int i915_dump_lrc(struct seq_file *m, void *unused)
+{
+ struct drm_info_node *node = (struct drm_info_node *) m->private;
+ struct drm_device *dev = node->minor->dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct intel_engine_cs *ring;
+ struct intel_context *ctx;
+ int ret, i;
+
+ if (!i915.enable_execlists) {
+ seq_printf(m, "Logical Ring Contexts are disabled\n");
+ return 0;
+ }
+
+ ret = mutex_lock_interruptible(&dev->struct_mutex);
+ if (ret)
+ return ret;
+
+ list_for_each_entry(ctx, &dev_priv->context_list, link) {
+ for_each_ring(ring, dev_priv, i) {
+ struct drm_i915_gem_object *ctx_obj = ctx->engine[i].state;
+
+ if (ring->default_context == ctx)
+ continue;
+
+ if (ctx_obj) {
+ struct page *page = i915_gem_object_get_page(ctx_obj, 1);
+ uint32_t *reg_state = kmap_atomic(page);
+ int j;
+
+ seq_printf(m, "CONTEXT: %s %u\n", ring->name,
+ intel_execlists_ctx_id(ctx_obj));
+
+ for (j = 0; j < 0x600 / sizeof(u32) / 4; j += 4) {
+ seq_printf(m, "\t[0x%08lx] 0x%08x 0x%08x 0x%08x 0x%08x\n",
+ i915_gem_obj_ggtt_offset(ctx_obj) + 4096 + (j * 4),
+ reg_state[j], reg_state[j + 1],
+ reg_state[j + 2], reg_state[j + 3]);
+ }
+ kunmap_atomic(reg_state);
+
+ seq_putc(m, '\n');
+ }
+ }
+ }
+
+ mutex_unlock(&dev->struct_mutex);
+
+ return 0;
+}
+
static int i915_execlists(struct seq_file *m, void *data)
{
struct drm_info_node *node = (struct drm_info_node *) m->private;
@@ -3999,6 +4050,7 @@ static const struct drm_info_list i915_debugfs_list[] = {
{"i915_opregion", i915_opregion, 0},
{"i915_gem_framebuffer", i915_gem_framebuffer_info, 0},
{"i915_context_status", i915_context_status, 0},
+ {"i915_dump_lrc", i915_dump_lrc, 0},
{"i915_execlists", i915_execlists, 0},
{"i915_gen6_forcewake_count", i915_gen6_forcewake_count_info, 0},
{"i915_swizzle_info", i915_swizzle_info, 0},
--
1.7.9.5