drm/i915/guc/slpc: Define and initialize boost frequency

Define helpers and struct members required to record boost info.
Boost frequency is initialized to RP0 at SLPC init. Also define num_waiters
which can track the pending boost requests.

Boost will be done by scheduling a worker thread. This will avoid
the need to make H2G calls inside an interrupt context. Initialize the
worker function during SLPC init as well. Had to move intel_guc_slpc_init
a few lines below to accommodate this.

v2: Add a workqueue to handle waitboost
v3: Code review comments (Ashutosh)

Cc: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211102012608.8609-2-vinay.belgaumkar@intel.com

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc_types.h b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc_types.h
index 41d13527666f..bf5b9a563c09 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc_types.h
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc_types.h
@@ -6,6 +6,9 @@
 #ifndef _INTEL_GUC_SLPC_TYPES_H_
 #define _INTEL_GUC_SLPC_TYPES_H_
 
+#include <linux/atomic.h>
+#include <linux/workqueue.h>
+#include <linux/mutex.h>
 #include <linux/types.h>
 
 #define SLPC_RESET_TIMEOUT_MS 5
@@ -20,10 +23,20 @@ struct intel_guc_slpc {
 	u32 min_freq;
 	u32 rp0_freq;
 	u32 rp1_freq;
+	u32 boost_freq;
 
 	/* frequency softlimits */
 	u32 min_freq_softlimit;
 	u32 max_freq_softlimit;
+
+	/* Protects set/reset of boost freq
+	 * and value of num_waiters
+	 */
+	struct mutex lock;
+
+	struct work_struct boost_work;
+	atomic_t num_waiters;
+	u32 num_boosts;
 };
 
 #endif