From: Jani Nikula Date: Thu, 28 Aug 2025 12:20:49 +0000 (+0300) Subject: drm/i915/wm: use generic poll_timeout_us() instead of wait_for() X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=7f38db435cf703cc432810362d84ed8be59202ea;p=users%2Fhch%2Fmisc.git drm/i915/wm: use generic poll_timeout_us() instead of wait_for() 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 500 us sleep instead. The timeout remains at 3 ms. Reviewed-by: Jouni Högander Link: https://lore.kernel.org/r/52c80860ea7b98e84f2386ed6cdd761f03190b1e.1756383233.git.jani.nikula@intel.com Signed-off-by: Jani Nikula --- diff --git a/drivers/gpu/drm/i915/display/i9xx_wm.c b/drivers/gpu/drm/i915/display/i9xx_wm.c index 591acce2a4b1..060aff765994 100644 --- a/drivers/gpu/drm/i915/display/i9xx_wm.c +++ b/drivers/gpu/drm/i915/display/i9xx_wm.c @@ -3,6 +3,8 @@ * Copyright © 2023 Intel Corporation */ +#include + #include "soc/intel_dram.h" #include "i915_drv.h" @@ -112,6 +114,7 @@ static const struct cxsr_latency *pnv_get_cxsr_latency(struct intel_display *dis static void chv_set_memory_dvfs(struct intel_display *display, bool enable) { u32 val; + int ret; vlv_punit_get(display->drm); @@ -124,8 +127,10 @@ static void chv_set_memory_dvfs(struct intel_display *display, bool enable) val |= FORCE_DDR_FREQ_REQ_ACK; vlv_punit_write(display->drm, PUNIT_REG_DDR_SETUP2, val); - if (wait_for((vlv_punit_read(display->drm, PUNIT_REG_DDR_SETUP2) & - FORCE_DDR_FREQ_REQ_ACK) == 0, 3)) + ret = poll_timeout_us(val = vlv_punit_read(display->drm, PUNIT_REG_DDR_SETUP2), + (val & FORCE_DDR_FREQ_REQ_ACK) == 0, + 500, 3000, false); + if (ret) drm_err(display->drm, "timed out waiting for Punit DDR DVFS request\n"); @@ -3905,6 +3910,7 @@ static void vlv_wm_get_hw_state(struct intel_display *display) struct vlv_wm_values *wm = &display->wm.vlv; struct intel_crtc *crtc; u32 val; + int ret; vlv_read_wm_values(display, wm); @@ -3931,8 +3937,10 @@ static void vlv_wm_get_hw_state(struct intel_display *display) val |= FORCE_DDR_FREQ_REQ_ACK; vlv_punit_write(display->drm, PUNIT_REG_DDR_SETUP2, val); - if (wait_for((vlv_punit_read(display->drm, PUNIT_REG_DDR_SETUP2) & - FORCE_DDR_FREQ_REQ_ACK) == 0, 3)) { + ret = poll_timeout_us(val = vlv_punit_read(display->drm, PUNIT_REG_DDR_SETUP2), + (val & FORCE_DDR_FREQ_REQ_ACK) == 0, + 500, 3000, false); + if (ret) { drm_dbg_kms(display->drm, "Punit not acking DDR DVFS request, " "assuming DDR DVFS is disabled\n");