[PATCH 02/16] drm/i915: Add a control file for pipe CRCs

Damien Lespiau
2013-10-15T17:55:53Z

Note the "return -ENODEV;" in pipe_crc_set_source(). The ctl file is
disabled until the end of the series to be able to do incremental
improvements.

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
---
drivers/gpu/drm/i915/i915_debugfs.c | 217 +++++++++++++++++++++++++++++++++++-
drivers/gpu/drm/i915/i915_drv.h | 8 ++
2 files changed, 223 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index e1d45aa..0d8a9a3 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -27,6 +27,7 @@
*/

#include <linux/seq_file.h>
+#include <linux/ctype.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
#include <linux/export.h>
@@ -1742,8 +1743,8 @@ static int i915_pipe_crc(struct seq_file *m, void *data)
int i;
int start;

- if (!IS_IVYBRIDGE(dev)) {
- seq_puts(m, "unsupported\n");
+ if (dev_priv->pipe_crc[pipe].source == INTEL_PIPE_CRC_SOURCE_NONE) {
+ seq_puts(m, "none\n");
return 0;
}

@@ -1762,6 +1763,217 @@ static int i915_pipe_crc(struct seq_file *m, void *data)
return 0;
}

+static const char *pipe_crc_sources[] = {
+ "none",
+ "plane1",
+ "plane2",
+ "pf",
+};
+
+static const char *pipe_crc_source_name(enum intel_pipe_crc_source source)
+{
+ BUILD_BUG_ON(ARRAY_SIZE(pipe_crc_sources) != INTEL_PIPE_CRC_SOURCE_MAX);
+ return pipe_crc_sources[source];
+}
+
+static int pipe_crc_ctl_show(struct seq_file *m, void *data)
+{
+ struct drm_device *dev = m->private;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ int i;
+
+ for (i = 0; i < I915_MAX_PIPES; i++)
+ seq_printf(m, "%c %s\n", pipe_name(i),
+ pipe_crc_source_name(dev_priv->pipe_crc[i].source));
+
+ return 0;
+}
+
+static int pipe_crc_ctl_open(struct inode *inode, struct file *file)
+{
+ struct drm_device *dev = inode->i_private;
+
+ return single_open(file, pipe_crc_ctl_show, dev);
+}
+
+static int pipe_crc_set_source(struct drm_device *dev, enum pipe pipe,
+ enum intel_pipe_crc_source source)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ u32 val;
+
+
+ return -ENODEV;
+
+ if (!IS_IVYBRIDGE(dev))
+ return -ENODEV;
+
+ dev_priv->pipe_crc[pipe].source = source;
+
+ switch (source) {
+ case INTEL_PIPE_CRC_SOURCE_PLANE1:
+ val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PRIMARY_IVB;
+ break;
+ case INTEL_PIPE_CRC_SOURCE_PLANE2:
+ val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_SPRITE_IVB;
+ break;
+ case INTEL_PIPE_CRC_SOURCE_PF:
+ val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PF_IVB;
+ break;
+ case INTEL_PIPE_CRC_SOURCE_NONE:
+ default:
+ val = 0;
+ break;
+ }
+
+ I915_WRITE(PIPE_CRC_CTL(pipe), val);
+ POSTING_READ(PIPE_CRC_CTL(pipe));
+
+ return 0;
+}
+
+/*
+ * Parse pipe CRC command strings:
+ * command: wsp* pipe wsp+ source wsp*
+ * pipe: (A | B | C)
+ * source: (none | plane1 | plane2 | pf)
+ * wsp: (#0x20 | #0x9 | #0xA)+
+ *
+ * eg.:
+ * "A plane1" -> Start CRC computations on plane1 of pipe A
+ * "A none" -> Stop CRC
+ */
+static int pipe_crc_ctl_tokenize(char *buf, char *words[], int max_words)
+{
+ int n_words = 0;
+
+ while (*buf) {
+ char *end;
+
+ /* skip leading white space */
+ buf = skip_spaces(buf);
+ if (!*buf)
+ break; /* end of buffer */
+
+ /* find end of word */
+ for (end = buf; *end && !isspace(*end); end++)
+ ;
+
+ if (n_words == max_words) {
+ DRM_DEBUG_DRIVER("too many words, allowed <= %d\n",
+ max_words);
+ return -EINVAL; /* ran out of words[] before bytes */
+ }
+
+ if (*end)
+ *end++ = '\0';
+ words[n_words++] = buf;
+ buf = end;
+ }
+
+ return n_words;
+}
+
+static int pipe_crc_ctl_parse_pipe(const char *buf, enum pipe *pipe)
+{
+ const char name = buf[0];
+
+ if (name < 'A' || name >= pipe_name(I915_MAX_PIPES))
+ return -EINVAL;
+
+ *pipe = name - 'A';
+
+ return 0;
+}
+
+static int
+pipe_crc_ctl_parse_source(const char *buf, enum intel_pipe_crc_source *source)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(pipe_crc_sources); i++)
+ if (!strcmp(buf, pipe_crc_sources[i])) {
+ *source = i;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static int pipe_crc_ctl_parse(struct drm_device *dev, char *buf, size_t len)
+{
+#define MAX_WORDS 2
+ int n_words;
+ char *words[MAX_WORDS];
+ enum pipe pipe;
+ enum intel_pipe_crc_source source;
+
+ n_words = pipe_crc_ctl_tokenize(buf, words, MAX_WORDS);
+ if (n_words != 2) {
+ DRM_DEBUG_DRIVER("tokenize failed, a command is 2 words\n");
+ return -EINVAL;
+ }
+
+ if (pipe_crc_ctl_parse_pipe(words[0], &pipe) < 0) {
+ DRM_DEBUG_DRIVER("unknown pipe %s\n", words[0]);
+ return -EINVAL;
+ }
+
+ if (pipe_crc_ctl_parse_source(words[1], &source) < 0) {
+ DRM_DEBUG_DRIVER("unknown source %s\n", words[1]);
+ return -EINVAL;
+ }
+
+ return pipe_crc_set_source(dev, pipe, source);
+}
+
+static ssize_t pipe_crc_ctl_write(struct file *file, const char __user *ubuf,
+ size_t len, loff_t *offp)
+{
+ struct seq_file *m = file->private_data;
+ struct drm_device *dev = m->private;
+ char *tmpbuf;
+ int ret;
+
+ if (len == 0)
+ return 0;
+
+ if (len > PAGE_SIZE - 1) {
+ DRM_DEBUG_DRIVER("expected <%lu bytes into pipe crc control\n",
+ PAGE_SIZE);
+ return -E2BIG;
+ }
+
+ tmpbuf = kmalloc(len + 1, GFP_KERNEL);
+ if (!tmpbuf)
+ return -ENOMEM;
+
+ if (copy_from_user(tmpbuf, ubuf, len)) {
+ ret = -EFAULT;
+ goto out;
+ }
+ tmpbuf[len] = '\0';
+
+ ret = pipe_crc_ctl_parse(dev, tmpbuf, len);
+
+out:
+ kfree(tmpbuf);
+ if (ret < 0)
+ return ret;
+
+ *offp += len;
+ return len;
+}
+
+static const struct file_operations i915_pipe_crc_ctl_fops = {
+ .owner = THIS_MODULE,
+ .open = pipe_crc_ctl_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+ .write = pipe_crc_ctl_write
+};
+
static int
i915_wedged_get(void *data, u64 *val)
{
@@ -2297,6 +2509,7 @@ static struct i915_debugfs_files {
{"i915_gem_drop_caches", &i915_drop_caches_fops},
{"i915_error_state", &i915_error_state_fops},
{"i915_next_seqno", &i915_next_seqno_fops},
+ {"i915_pipe_crc_ctl", &i915_pipe_crc_ctl_fops},
};

int i915_debugfs_init(struct drm_minor *minor)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 6855d91..0d564eb 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1219,6 +1219,14 @@ struct i915_package_c8 {
} regsave;
};

+enum intel_pipe_crc_source {
+ INTEL_PIPE_CRC_SOURCE_NONE,
+ INTEL_PIPE_CRC_SOURCE_PLANE1,
+ INTEL_PIPE_CRC_SOURCE_PLANE2,
+ INTEL_PIPE_CRC_SOURCE_PF,
+ INTEL_PIPE_CRC_SOURCE_MAX,
+};
+
struct intel_pipe_crc_entry {
uint32_t timestamp;
uint32_t crc[5];
--
1.8.3.1