drm/lima: Add optional devfreq and cooling device support

Most platforms with a Mali-400 or Mali-450 GPU also have support for
changing the GPU clock frequency. Add devfreq support so the GPU clock
rate is updated based on the actual GPU usage when the
"operating-points-v2" property is present in the board.dts.

The actual devfreq code is taken from panfrost_devfreq.c and modified so
it matches what the lima hardware needs:
- a call to dev_pm_opp_set_clkname() during initialization because there
  are two clocks on Mali-4x0 IPs. "core" is the one that actually clocks
  the GPU so we need to control it using devfreq.
- locking when reading or writing the devfreq statistics because (unlike
  than panfrost) we have multiple PP and GP IRQs which may finish jobs
  concurrently.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200319203427.2259891-3-martin.blumenstingl@googlemail.com

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/drm/lima/lima_sched.h b/drivers/gpu/drm/lima/lima_sched.h
index 02dfa14d7083..90f03c48ef4a 100644
--- a/drivers/gpu/drm/lima/lima_sched.h
+++ b/drivers/gpu/drm/lima/lima_sched.h
@@ -8,6 +8,7 @@
 #include <linux/list.h>
 #include <linux/xarray.h>
 
+struct lima_device;
 struct lima_vm;
 
 struct lima_sched_error_task {
@@ -52,6 +53,8 @@ struct lima_sched_pipe {
 	u32 fence_seqno;
 	spinlock_t fence_lock;
 
+	struct lima_device *ldev;
+
 	struct lima_sched_task *current_task;
 	struct lima_vm *current_vm;