diff options
| -rw-r--r-- | drivers/gpu/drm/i915/intel_cdclk.c | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_cdclk.c b/drivers/gpu/drm/i915/intel_cdclk.c index 1b31d82b2cfe..0e892b8c84af 100644 --- a/drivers/gpu/drm/i915/intel_cdclk.c +++ b/drivers/gpu/drm/i915/intel_cdclk.c @@ -1452,6 +1452,112 @@ static void cnl_get_cdclk(struct drm_i915_private *dev_priv, cdclk_state->cdclk = DIV_ROUND_CLOSEST(cdclk_state->vco, div); } +static void cnl_cdclk_pll_disable(struct drm_i915_private *dev_priv) +{ + u32 val; + + val = I915_READ(BXT_DE_PLL_ENABLE); + val &= ~BXT_DE_PLL_PLL_ENABLE; + I915_WRITE(BXT_DE_PLL_ENABLE, val); + + /* Timeout 200us */ + if (wait_for((I915_READ(BXT_DE_PLL_ENABLE) & BXT_DE_PLL_LOCK) == 0, 1)) + DRM_ERROR("timout waiting for CDCLK PLL unlock\n"); + + dev_priv->cdclk.hw.vco = 0; +} + +static void cnl_cdclk_pll_enable(struct drm_i915_private *dev_priv, int vco) +{ + int ratio = DIV_ROUND_CLOSEST(vco, dev_priv->cdclk.hw.ref); + u32 val; + + val = CNL_CDCLK_PLL_RATIO(ratio); + I915_WRITE(BXT_DE_PLL_ENABLE, val); + + val |= BXT_DE_PLL_PLL_ENABLE; + I915_WRITE(BXT_DE_PLL_ENABLE, val); + + /* Timeout 200us */ + if (wait_for((I915_READ(BXT_DE_PLL_ENABLE) & BXT_DE_PLL_LOCK) != 0, 1)) + DRM_ERROR("timout waiting for CDCLK PLL lock\n"); + + dev_priv->cdclk.hw.vco = vco; +} + +__attribute__((unused)) +static void cnl_set_cdclk(struct drm_i915_private *dev_priv, + const struct intel_cdclk_state *cdclk_state) +{ + int cdclk = cdclk_state->cdclk; + int vco = cdclk_state->vco; + u32 val, divider, pcu_ack; + int ret; + + mutex_lock(&dev_priv->rps.hw_lock); + ret = skl_pcode_request(dev_priv, SKL_PCODE_CDCLK_CONTROL, + SKL_CDCLK_PREPARE_FOR_CHANGE, + SKL_CDCLK_READY_FOR_CHANGE, + SKL_CDCLK_READY_FOR_CHANGE, 3); + mutex_unlock(&dev_priv->rps.hw_lock); + if (ret) { + DRM_ERROR("Failed to inform PCU about cdclk change (%d)\n", + ret); + return; + } + + /* cdclk = vco / 2 / div{1,2} */ + switch (DIV_ROUND_CLOSEST(vco, cdclk)) { + case 4: + divider = BXT_CDCLK_CD2X_DIV_SEL_2; + break; + case 2: + divider = BXT_CDCLK_CD2X_DIV_SEL_1; + break; + default: + WARN_ON(cdclk != dev_priv->cdclk.hw.ref); + WARN_ON(vco != 0); + + divider = BXT_CDCLK_CD2X_DIV_SEL_1; + break; + } + + switch (cdclk) { + case 528000: + pcu_ack = 2; + break; + case 336000: + pcu_ack = 1; + break; + case 168000: + default: + pcu_ack = 0; + break; + } + + if (dev_priv->cdclk.hw.vco != 0 && + dev_priv->cdclk.hw.vco != vco) + cnl_cdclk_pll_disable(dev_priv); + + if (dev_priv->cdclk.hw.vco != vco) + cnl_cdclk_pll_enable(dev_priv, vco); + + val = divider | skl_cdclk_decimal(cdclk); + /* + * FIXME if only the cd2x divider needs changing, it could be done + * without shutting off the pipe (if only one pipe is active). + */ + val |= BXT_CDCLK_CD2X_PIPE_NONE; + I915_WRITE(CDCLK_CTL, val); + + /* inform PCU of the change */ + mutex_lock(&dev_priv->rps.hw_lock); + sandybridge_pcode_write(dev_priv, SKL_PCODE_CDCLK_CONTROL, pcu_ack); + mutex_unlock(&dev_priv->rps.hw_lock); + + intel_update_cdclk(dev_priv); +} + /** * intel_cdclk_state_compare - Determine if two CDCLK states differ * @a: first CDCLK state |