[PATCH v3 05/13] drm/i915/dmc: Add interface to block PKG C-state

[Jouni Högander]

Add interface to block PKG C-state. This is needed to implement workaround
for underrun on idle PSR HW issue (Wa_16025596647).

Bspec: 74151
Signed-off-by: Jouni Högander <jouni.hogander at intel.com>
---
 drivers/gpu/drm/i915/display/intel_dmc.c | 17 +++++++++++++++++
 drivers/gpu/drm/i915/display/intel_dmc.h |  2 ++
 2 files changed, 19 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_dmc.c b/drivers/gpu/drm/i915/display/intel_dmc.c
index 98f80a6c63e8..c65544e48c42 100644
--- a/drivers/gpu/drm/i915/display/intel_dmc.c
+++ b/drivers/gpu/drm/i915/display/intel_dmc.c
@@ -517,6 +517,23 @@ void intel_dmc_disable_pipe(struct intel_display *display, enum pipe pipe)
 		intel_de_rmw(display, PIPEDMC_CONTROL(pipe), PIPEDMC_ENABLE, 0);
 }
 
+/**
+ * intel_dmc_block_pkgc() - block PKG C-state
+ * @display: display instance
+ * @pipe: pipe which register use to block
+ * @block: block/unblock
+ *
+ * This interface is target for Wa_16025596647 usage. I.e. to set/clear
+ * PIPEDMC_BLOCK_PKGC_SW_BLOCK_PKGC_ALWAYS bit in PIPEDMC_BLOCK_PKGC_SW register.
+ */
+void intel_dmc_block_pkgc(struct intel_display *display, enum pipe pipe,
+			  bool block)
+{
+	intel_de_rmw(display, PIPEDMC_BLOCK_PKGC_SW(pipe),
+		     PIPEDMC_BLOCK_PKGC_SW_BLOCK_PKGC_ALWAYS, block ?
+		     PIPEDMC_BLOCK_PKGC_SW_BLOCK_PKGC_ALWAYS : 0);
+}
+
 static bool is_dmc_evt_ctl_reg(struct intel_display *display,
 			       enum intel_dmc_id dmc_id, i915_reg_t reg)
 {
diff --git a/drivers/gpu/drm/i915/display/intel_dmc.h b/drivers/gpu/drm/i915/display/intel_dmc.h
index c78426eb4cd5..236312fb791c 100644
--- a/drivers/gpu/drm/i915/display/intel_dmc.h
+++ b/drivers/gpu/drm/i915/display/intel_dmc.h
@@ -18,6 +18,8 @@ void intel_dmc_load_program(struct intel_display *display);
 void intel_dmc_disable_program(struct intel_display *display);
 void intel_dmc_enable_pipe(struct intel_display *display, enum pipe pipe);
 void intel_dmc_disable_pipe(struct intel_display *display, enum pipe pipe);
+void intel_dmc_block_pkgc(struct intel_display *display, enum pipe pipe,
+			  bool block);
 void intel_dmc_fini(struct intel_display *display);
 void intel_dmc_suspend(struct intel_display *display);
 void intel_dmc_resume(struct intel_display *display);
-- 
2.43.0