[igt-dev] [PATCH i-g-t 1/5] lib/igt_pm: igt lib helper routines to support DC5/6 tests

[Anshuman Gupta]

From: Jyoti Yadav <jyoti.r.yadav at intel.com>

dmc_loaded() will be used by new test i915_pm_dc.c which will validate
Display C States. So moving the same to igt_pm library.
Introduced igt_disable_runtime_pm() inorder to disable runtime suspend
for the function which support dc9.

v2: Simplify the comment section.
v3: Remove . from the subject line.
v4: Rebased, resolve conflicts in pm_rpm.c
    Included patch set version change log.
v5: Listing actual change in patch set changelog to make review easier.
v6: igt's lib added support for disabling runtime suspend, change in commit log.
    rebased due to test name pm_rpm changed to i915_pm_rpm.
v7: Addressed review comment by saving POWER_DIR values in igt_disable_runtime_pm().

Signed-off-by: Jyoti Yadav <jyoti.r.yadav at intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
---
 lib/igt_pm.c             | 82 ++++++++++++++++++++++++++++++++++++++++++++++++
 lib/igt_pm.h             |  2 ++
 tests/i915/i915_pm_rpm.c | 17 +---------
 3 files changed, 85 insertions(+), 16 deletions(-)

diff --git a/lib/igt_pm.c b/lib/igt_pm.c
index 4902723..0e999b0 100644
--- a/lib/igt_pm.c
+++ b/lib/igt_pm.c
@@ -38,6 +38,7 @@
 #include "drmtest.h"
 #include "igt_pm.h"
 #include "igt_aux.h"
+#include "igt_sysfs.h"
 
 /**
  * SECTION:igt_pm
@@ -577,6 +578,60 @@ bool igt_setup_runtime_pm(void)
 	return true;
 }
 
+bool igt_disable_runtime_pm(void)
+{
+	int fd;
+	ssize_t size;
+	char buf[6];
+
+	if (pm_status_fd < 0) {
+		fd = open(POWER_DIR "/autosuspend_delay_ms", O_RDWR);
+		if (fd < 0)
+			return false;
+
+		size = read(fd, __igt_pm_runtime_autosuspend,
+			    sizeof(__igt_pm_runtime_autosuspend));
+
+		if (size <= 0) {
+			close(fd);
+			return false;
+		}
+
+		strchomp(__igt_pm_runtime_autosuspend);
+		igt_install_exit_handler(__igt_pm_runtime_exit_handler);
+		close(fd);
+	}
+
+	/* We know we support runtime PM, let's try to disable it now. */
+	fd = open(POWER_DIR "/control", O_RDWR);
+	igt_assert_f(fd >= 0, "Can't open " POWER_DIR "/control\n");
+
+	if (pm_status_fd < 0) {
+		igt_assert(read(fd, __igt_pm_runtime_control,
+				sizeof(__igt_pm_runtime_control)) > 0);
+		strchomp(__igt_pm_runtime_control);
+
+		igt_debug("Saved runtime power management as '%s' and '%s'\n",
+			  __igt_pm_runtime_autosuspend, __igt_pm_runtime_control);
+	}
+
+	size = write(fd, "on\n", 3);
+	igt_assert(size == 3);
+	lseek(fd, 0, SEEK_SET);
+	size = read(fd, buf, ARRAY_SIZE(buf));
+	igt_assert(size == 3);
+	igt_assert(strncmp(buf, "on\n", 3) == 0);
+	close(fd);
+
+	if (pm_status_fd < 0) {
+		pm_status_fd = open(POWER_DIR "/runtime_status", O_RDONLY);
+		igt_assert_f(pm_status_fd >= 0,
+			     "Can't open " POWER_DIR "/runtime_status\n");
+	}
+
+	return true;
+}
+
 /**
  * igt_get_runtime_pm_status:
  *
@@ -620,3 +675,30 @@ bool igt_wait_for_pm_status(enum igt_runtime_pm_status status)
 {
 	return igt_wait(igt_get_runtime_pm_status() == status, 10000, 100);
 }
+
+/**
+ * dmc_loaded:
+ * @debugfs: fd to the debugfs dir.
+
+ * Check whether DMC FW is loaded or not. DMC FW is require for few Display C
+ * states like DC5 and DC6. FW does the Context Save and Restore during Display
+ * C States entry and exit.
+ *
+ * Returns:
+ * True if DMC FW is loaded otherwise false.
+ */
+bool igt_pm_dmc_loaded(int debugfs)
+{
+	igt_require(debugfs != -1);
+	char buf[15];
+	int len;
+
+	len = igt_sysfs_read(debugfs, "i915_dmc_info", buf, sizeof(buf) - 1);
+	if (len < 0)
+		return true; /* no CSR support, no DMC requirement */
+
+	buf[len] = '\0';
+
+	igt_info("DMC: %s\n", buf);
+	return strstr(buf, "fw loaded: yes");
+}
diff --git a/lib/igt_pm.h b/lib/igt_pm.h
index 10cc679..6c4617a 100644
--- a/lib/igt_pm.h
+++ b/lib/igt_pm.h
@@ -47,8 +47,10 @@ enum igt_runtime_pm_status {
 };
 
 bool igt_setup_runtime_pm(void);
+bool igt_disable_runtime_pm(void);
 void igt_restore_runtime_pm(void);
 enum igt_runtime_pm_status igt_get_runtime_pm_status(void);
 bool igt_wait_for_pm_status(enum igt_runtime_pm_status status);
+bool igt_pm_dmc_loaded(int debugfs);
 
 #endif /* IGT_PM_H */
diff --git a/tests/i915/i915_pm_rpm.c b/tests/i915/i915_pm_rpm.c
index be296f5..2d7cb5e 100644
--- a/tests/i915/i915_pm_rpm.c
+++ b/tests/i915/i915_pm_rpm.c
@@ -710,21 +710,6 @@ static void setup_pc8(void)
 	has_pc8 = true;
 }
 
-static bool dmc_loaded(void)
-{
-	char buf[15];
-	int len;
-
-	len = igt_sysfs_read(debugfs, "i915_dmc_info", buf, sizeof(buf) - 1);
-	if (len < 0)
-	    return true; /* no CSR support, no DMC requirement */
-
-	buf[len] = '\0';
-
-	igt_info("DMC: %s\n", buf);
-	return strstr(buf, "fw loaded: yes");
-}
-
 static void dump_file(int dir, const char *filename)
 {
 	char *contents;
@@ -761,7 +746,7 @@ static bool setup_environment(void)
 	igt_info("Runtime PM support: %d\n", has_runtime_pm);
 	igt_info("PC8 residency support: %d\n", has_pc8);
 	igt_require(has_runtime_pm);
-	igt_require(dmc_loaded());
+	igt_require(igt_pm_dmc_loaded(debugfs));
 
 out:
 	disable_all_screens(&ms_data);
-- 
2.7.4