drm/i915/power-well: use generic poll_timeout_us() instead of wait_for() for DKL PHY

Prefer generic poll helpers over i915 custom helpers.

The functional change is losing the exponentially growing sleep of
wait_for(), which used to be 10, 20, 40, ..., 640, and 1280 us.

Use an arbitrary constant 100 us sleep instead. The timeout remains at 1
ms.

Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Link: https://lore.kernel.org/r/663c9edf4a98b09121d7200f8d734ebc829da85b.1756383233.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/display/intel_display_power_well.c b/drivers/gpu/drm/i915/display/intel_display_power_well.c
index 0c48d9cf35288c3a72ecbc6429c1fd33af740a48..c7a1fcb9d6ad2367d59a9bb854924d4643cc445f 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_display_power_well.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power_well.c
@@ -3,6 +3,8 @@
  * Copyright © 2022 Intel Corporation
  */
 
+#include <linux/iopoll.h>
+
 #include "i915_drv.h"
 #include "i915_irq.h"
 #include "i915_reg.h"
@@ -527,6 +529,8 @@ icl_tc_phy_aux_power_well_enable(struct intel_display *display,
        const struct i915_power_well_regs *regs = power_well->desc->ops->regs;
        bool is_tbt = power_well->desc->is_tc_tbt;
        bool timeout_expected;
+       u32 val;
+       int ret;
 
        icl_tc_port_assert_ref_held(display, power_well, dig_port);
 
@@ -553,10 +557,11 @@ icl_tc_phy_aux_power_well_enable(struct intel_display *display,
 
                tc_port = TGL_AUX_PW_TO_TC_PORT(i915_power_well_instance(power_well)->hsw.idx);
 
-               if (wait_for(intel_dkl_phy_read(display, DKL_CMN_UC_DW_27(tc_port)) &
-                            DKL_CMN_UC_DW27_UC_HEALTH, 1))
-                       drm_warn(display->drm,
-                                "Timeout waiting TC uC health\n");
+               ret = poll_timeout_us(val = intel_dkl_phy_read(display, DKL_CMN_UC_DW_27(tc_port)),
+                                     val & DKL_CMN_UC_DW27_UC_HEALTH,
+                                     100, 1000, false);
+               if (ret)
+                       drm_warn(display->drm, "Timeout waiting TC uC health\n");
        }
 }