From: Jani Nikula Date: Thu, 28 Aug 2025 12:20:50 +0000 (+0300) Subject: drm/i915/cdclk: use generic poll_timeout_us() instead of wait_for() X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=032a3bd4d673a3efb2575914bd96ea60c9124993;p=users%2Fhch%2Fmisc.git drm/i915/cdclk: 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 50 ms. Reviewed-by: Jouni Högander Link: https://lore.kernel.org/r/6d50031411d5517508867d4b595ce90a2b44073b.1756383233.git.jani.nikula@intel.com Signed-off-by: Jani Nikula --- diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c index d7ba3970e1e9..9725eebe5706 100644 --- a/drivers/gpu/drm/i915/display/intel_cdclk.c +++ b/drivers/gpu/drm/i915/display/intel_cdclk.c @@ -22,6 +22,7 @@ */ #include +#include #include #include @@ -673,6 +674,7 @@ static void vlv_set_cdclk(struct intel_display *display, int cdclk = cdclk_config->cdclk; u32 val, cmd = cdclk_config->voltage_level; intel_wakeref_t wakeref; + int ret; switch (cdclk) { case 400000: @@ -703,12 +705,12 @@ static void vlv_set_cdclk(struct intel_display *display, val &= ~DSPFREQGUAR_MASK; val |= (cmd << DSPFREQGUAR_SHIFT); vlv_punit_write(display->drm, PUNIT_REG_DSPSSPM, val); - if (wait_for((vlv_punit_read(display->drm, PUNIT_REG_DSPSSPM) & - DSPFREQSTAT_MASK) == (cmd << DSPFREQSTAT_SHIFT), - 50)) { - drm_err(display->drm, - "timed out waiting for CDclk change\n"); - } + + ret = poll_timeout_us(val = vlv_punit_read(display->drm, PUNIT_REG_DSPSSPM), + (val & DSPFREQSTAT_MASK) == (cmd << DSPFREQSTAT_SHIFT), + 500, 50 * 1000, false); + if (ret) + drm_err(display->drm, "timed out waiting for CDCLK change\n"); if (cdclk == 400000) { u32 divider; @@ -722,11 +724,11 @@ static void vlv_set_cdclk(struct intel_display *display, val |= divider; vlv_cck_write(display->drm, CCK_DISPLAY_CLOCK_CONTROL, val); - if (wait_for((vlv_cck_read(display->drm, CCK_DISPLAY_CLOCK_CONTROL) & - CCK_FREQUENCY_STATUS) == (divider << CCK_FREQUENCY_STATUS_SHIFT), - 50)) - drm_err(display->drm, - "timed out waiting for CDclk change\n"); + ret = poll_timeout_us(val = vlv_cck_read(display->drm, CCK_DISPLAY_CLOCK_CONTROL), + (val & CCK_FREQUENCY_STATUS) == (divider << CCK_FREQUENCY_STATUS_SHIFT), + 500, 50 * 1000, false); + if (ret) + drm_err(display->drm, "timed out waiting for CDCLK change\n"); } /* adjust self-refresh exit latency value */ @@ -762,6 +764,7 @@ static void chv_set_cdclk(struct intel_display *display, int cdclk = cdclk_config->cdclk; u32 val, cmd = cdclk_config->voltage_level; intel_wakeref_t wakeref; + int ret; switch (cdclk) { case 333333: @@ -787,12 +790,12 @@ static void chv_set_cdclk(struct intel_display *display, val &= ~DSPFREQGUAR_MASK_CHV; val |= (cmd << DSPFREQGUAR_SHIFT_CHV); vlv_punit_write(display->drm, PUNIT_REG_DSPSSPM, val); - if (wait_for((vlv_punit_read(display->drm, PUNIT_REG_DSPSSPM) & - DSPFREQSTAT_MASK_CHV) == (cmd << DSPFREQSTAT_SHIFT_CHV), - 50)) { - drm_err(display->drm, - "timed out waiting for CDclk change\n"); - } + + ret = poll_timeout_us(val = vlv_punit_read(display->drm, PUNIT_REG_DSPSSPM), + (val & DSPFREQSTAT_MASK_CHV) == (cmd << DSPFREQSTAT_SHIFT_CHV), + 500, 50 * 1000, false); + if (ret) + drm_err(display->drm, "timed out waiting for CDCLK change\n"); vlv_punit_put(display->drm);