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path: root/drivers/gpu/drm/i915/display/intel_dpll_mgr.c
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Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_dpll_mgr.c')
-rw-r--r--drivers/gpu/drm/i915/display/intel_dpll_mgr.c221
1 files changed, 153 insertions, 68 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_dpll_mgr.c b/drivers/gpu/drm/i915/display/intel_dpll_mgr.c
index e08684e34078..f6ad257a260e 100644
--- a/drivers/gpu/drm/i915/display/intel_dpll_mgr.c
+++ b/drivers/gpu/drm/i915/display/intel_dpll_mgr.c
@@ -141,7 +141,7 @@ void assert_shared_dpll(struct drm_i915_private *dev_priv,
"asserting DPLL %s with no DPLL\n", onoff(state)))
return;
- cur_state = pll->info->funcs->get_hw_state(dev_priv, pll, &hw_state);
+ cur_state = intel_dpll_get_hw_state(dev_priv, pll, &hw_state);
I915_STATE_WARN(cur_state != state,
"%s assertion failure (expected %s, current %s)\n",
pll->info->name, onoff(state), onoff(cur_state));
@@ -151,14 +151,14 @@ static i915_reg_t
intel_combo_pll_enable_reg(struct drm_i915_private *i915,
struct intel_shared_dpll *pll)
{
-
- if (IS_ELKHARTLAKE(i915) && (pll->info->id == DPLL_ID_EHL_DPLL4))
+ if (IS_DG1(i915))
+ return DG1_DPLL_ENABLE(pll->info->id);
+ else if (IS_JSL_EHL(i915) && (pll->info->id == DPLL_ID_EHL_DPLL4))
return MG_PLL_ENABLE(0);
return CNL_DPLL_ENABLE(pll->info->id);
-
-
}
+
/**
* intel_prepare_shared_dpll - call a dpll's prepare hook
* @crtc_state: CRTC, and its state, which has a shared dpll
@@ -891,11 +891,12 @@ hsw_ddi_wrpll_get_dpll(struct intel_atomic_state *state,
}
static int hsw_ddi_wrpll_get_freq(struct drm_i915_private *dev_priv,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
int refclk;
int n, p, r;
- u32 wrpll = pll->state.hw_state.wrpll;
+ u32 wrpll = pll_state->wrpll;
switch (wrpll & WRPLL_REF_MASK) {
case WRPLL_REF_SPECIAL_HSW:
@@ -962,7 +963,8 @@ hsw_ddi_lcpll_get_dpll(struct intel_crtc_state *crtc_state)
}
static int hsw_ddi_lcpll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
int link_clock = 0;
@@ -1002,11 +1004,12 @@ hsw_ddi_spll_get_dpll(struct intel_atomic_state *state,
}
static int hsw_ddi_spll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
int link_clock = 0;
- switch (pll->state.hw_state.spll & SPLL_FREQ_MASK) {
+ switch (pll_state->spll & SPLL_FREQ_MASK) {
case SPLL_FREQ_810MHz:
link_clock = 81000;
break;
@@ -1577,9 +1580,9 @@ static bool skl_ddi_hdmi_pll_dividers(struct intel_crtc_state *crtc_state)
}
static int skl_ddi_wrpll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
- const struct intel_dpll_hw_state *pll_state = &pll->state.hw_state;
int ref_clock = i915->dpll.ref_clks.nssc;
u32 p0, p1, p2, dco_freq;
@@ -1602,9 +1605,19 @@ static int skl_ddi_wrpll_get_freq(struct drm_i915_private *i915,
case DPLL_CFGCR2_PDIV_3:
p0 = 3;
break;
+ case DPLL_CFGCR2_PDIV_7_INVALID:
+ /*
+ * Incorrect ASUS-Z170M BIOS setting, the HW seems to ignore bit#0,
+ * handling it the same way as PDIV_7.
+ */
+ drm_dbg_kms(&i915->drm, "Invalid WRPLL PDIV divider value, fixing it.\n");
+ fallthrough;
case DPLL_CFGCR2_PDIV_7:
p0 = 7;
break;
+ default:
+ MISSING_CASE(p0);
+ return 0;
}
switch (p2) {
@@ -1620,6 +1633,9 @@ static int skl_ddi_wrpll_get_freq(struct drm_i915_private *i915,
case DPLL_CFGCR2_KDIV_1:
p2 = 1;
break;
+ default:
+ MISSING_CASE(p2);
+ return 0;
}
dco_freq = (pll_state->cfgcr1 & DPLL_CFGCR1_DCO_INTEGER_MASK) *
@@ -1675,12 +1691,12 @@ skl_ddi_dp_set_dpll_hw_state(struct intel_crtc_state *crtc_state)
}
static int skl_ddi_lcpll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
int link_clock = 0;
- switch ((pll->state.hw_state.ctrl1 &
- DPLL_CTRL1_LINK_RATE_MASK(0)) >>
+ switch ((pll_state->ctrl1 & DPLL_CTRL1_LINK_RATE_MASK(0)) >>
DPLL_CTRL1_LINK_RATE_SHIFT(0)) {
case DPLL_CTRL1_LINK_RATE_810:
link_clock = 81000;
@@ -1758,16 +1774,17 @@ static bool skl_get_dpll(struct intel_atomic_state *state,
}
static int skl_ddi_pll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
/*
* ctrl1 register is already shifted for each pll, just use 0 to get
* the internal shift for each field
*/
- if (pll->state.hw_state.ctrl1 & DPLL_CTRL1_HDMI_MODE(0))
- return skl_ddi_wrpll_get_freq(i915, pll);
+ if (pll_state->ctrl1 & DPLL_CTRL1_HDMI_MODE(0))
+ return skl_ddi_wrpll_get_freq(i915, pll, pll_state);
else
- return skl_ddi_lcpll_get_freq(i915, pll);
+ return skl_ddi_lcpll_get_freq(i915, pll, pll_state);
}
static void skl_update_dpll_ref_clks(struct drm_i915_private *i915)
@@ -2205,9 +2222,9 @@ bxt_ddi_hdmi_set_dpll_hw_state(struct intel_crtc_state *crtc_state)
}
static int bxt_ddi_pll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
- const struct intel_dpll_hw_state *pll_state = &pll->state.hw_state;
struct dpll clock;
clock.m1 = 2;
@@ -2622,11 +2639,25 @@ static bool cnl_ddi_hdmi_pll_dividers(struct intel_crtc_state *crtc_state)
return true;
}
+/*
+ * Display WA #22010492432: ehl, tgl
+ * Program half of the nominal DCO divider fraction value.
+ */
+static bool
+ehl_combo_pll_div_frac_wa_needed(struct drm_i915_private *i915)
+{
+ return ((IS_PLATFORM(i915, INTEL_ELKHARTLAKE) &&
+ IS_JSL_EHL_REVID(i915, EHL_REVID_B0, REVID_FOREVER)) ||
+ IS_TIGERLAKE(i915)) &&
+ i915->dpll.ref_clks.nssc == 38400;
+}
+
static int __cnl_ddi_wrpll_get_freq(struct drm_i915_private *dev_priv,
const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state,
int ref_clock)
{
- const struct intel_dpll_hw_state *pll_state = &pll->state.hw_state;
+ u32 dco_fraction;
u32 p0, p1, p2, dco_freq;
p0 = pll_state->cfgcr1 & DPLL_CFGCR1_PDIV_MASK;
@@ -2669,8 +2700,13 @@ static int __cnl_ddi_wrpll_get_freq(struct drm_i915_private *dev_priv,
dco_freq = (pll_state->cfgcr0 & DPLL_CFGCR0_DCO_INTEGER_MASK) *
ref_clock;
- dco_freq += (((pll_state->cfgcr0 & DPLL_CFGCR0_DCO_FRACTION_MASK) >>
- DPLL_CFGCR0_DCO_FRACTION_SHIFT) * ref_clock) / 0x8000;
+ dco_fraction = (pll_state->cfgcr0 & DPLL_CFGCR0_DCO_FRACTION_MASK) >>
+ DPLL_CFGCR0_DCO_FRACTION_SHIFT;
+
+ if (ehl_combo_pll_div_frac_wa_needed(dev_priv))
+ dco_fraction *= 2;
+
+ dco_freq += (dco_fraction * ref_clock) / 0x8000;
if (drm_WARN_ON(&dev_priv->drm, p0 == 0 || p1 == 0 || p2 == 0))
return 0;
@@ -2679,9 +2715,11 @@ static int __cnl_ddi_wrpll_get_freq(struct drm_i915_private *dev_priv,
}
static int cnl_ddi_wrpll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
- return __cnl_ddi_wrpll_get_freq(i915, pll, i915->dpll.ref_clks.nssc);
+ return __cnl_ddi_wrpll_get_freq(i915, pll, pll_state,
+ i915->dpll.ref_clks.nssc);
}
static bool
@@ -2730,11 +2768,12 @@ cnl_ddi_dp_set_dpll_hw_state(struct intel_crtc_state *crtc_state)
}
static int cnl_ddi_lcpll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
int link_clock = 0;
- switch (pll->state.hw_state.cfgcr0 & DPLL_CFGCR0_LINK_RATE_MASK) {
+ switch (pll_state->cfgcr0 & DPLL_CFGCR0_LINK_RATE_MASK) {
case DPLL_CFGCR0_LINK_RATE_810:
link_clock = 81000;
break;
@@ -2817,12 +2856,13 @@ static bool cnl_get_dpll(struct intel_atomic_state *state,
}
static int cnl_ddi_pll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
- if (pll->state.hw_state.cfgcr0 & DPLL_CFGCR0_HDMI_MODE)
- return cnl_ddi_wrpll_get_freq(i915, pll);
+ if (pll_state->cfgcr0 & DPLL_CFGCR0_HDMI_MODE)
+ return cnl_ddi_wrpll_get_freq(i915, pll, pll_state);
else
- return cnl_ddi_lcpll_get_freq(i915, pll);
+ return cnl_ddi_lcpll_get_freq(i915, pll, pll_state);
}
static void cnl_update_dpll_ref_clks(struct drm_i915_private *i915)
@@ -2948,16 +2988,6 @@ static const struct skl_wrpll_params tgl_tbt_pll_24MHz_values = {
/* the following params are unused */
};
-/*
- * Display WA #22010492432: tgl
- * Divide the nominal .dco_fraction value by 2.
- */
-static const struct skl_wrpll_params tgl_tbt_pll_38_4MHz_values = {
- .dco_integer = 0x54, .dco_fraction = 0x1800,
- /* the following params are unused */
- .pdiv = 0, .kdiv = 0, .qdiv_mode = 0, .qdiv_ratio = 0,
-};
-
static bool icl_calc_dp_combo_pll(struct intel_crtc_state *crtc_state,
struct skl_wrpll_params *pll_params)
{
@@ -2991,14 +3021,12 @@ static bool icl_calc_tbt_pll(struct intel_crtc_state *crtc_state,
MISSING_CASE(dev_priv->dpll.ref_clks.nssc);
fallthrough;
case 19200:
+ case 38400:
*pll_params = tgl_tbt_pll_19_2MHz_values;
break;
case 24000:
*pll_params = tgl_tbt_pll_24MHz_values;
break;
- case 38400:
- *pll_params = tgl_tbt_pll_38_4MHz_values;
- break;
}
} else {
switch (dev_priv->dpll.ref_clks.nssc) {
@@ -3019,7 +3047,8 @@ static bool icl_calc_tbt_pll(struct intel_crtc_state *crtc_state,
}
static int icl_ddi_tbt_pll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
/*
* The PLL outputs multiple frequencies at the same time, selection is
@@ -3055,9 +3084,10 @@ icl_calc_wrpll(struct intel_crtc_state *crtc_state,
}
static int icl_ddi_combo_pll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
- return __cnl_ddi_wrpll_get_freq(i915, pll,
+ return __cnl_ddi_wrpll_get_freq(i915, pll, pll_state,
icl_wrpll_ref_clock(i915));
}
@@ -3065,9 +3095,14 @@ static void icl_calc_dpll_state(struct drm_i915_private *i915,
const struct skl_wrpll_params *pll_params,
struct intel_dpll_hw_state *pll_state)
{
+ u32 dco_fraction = pll_params->dco_fraction;
+
memset(pll_state, 0, sizeof(*pll_state));
- pll_state->cfgcr0 = DPLL_CFGCR0_DCO_FRACTION(pll_params->dco_fraction) |
+ if (ehl_combo_pll_div_frac_wa_needed(i915))
+ dco_fraction = DIV_ROUND_CLOSEST(dco_fraction, 2);
+
+ pll_state->cfgcr0 = DPLL_CFGCR0_DCO_FRACTION(dco_fraction) |
pll_params->dco_integer;
pll_state->cfgcr1 = DPLL_CFGCR1_QDIV_RATIO(pll_params->qdiv_ratio) |
@@ -3377,9 +3412,9 @@ static bool icl_calc_mg_pll_state(struct intel_crtc_state *crtc_state,
}
static int icl_ddi_mg_pll_get_freq(struct drm_i915_private *dev_priv,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
- const struct intel_dpll_hw_state *pll_state = &pll->state.hw_state;
u32 m1, m2_int, m2_frac, div1, div2, ref_clock;
u64 tmp;
@@ -3524,12 +3559,22 @@ static bool icl_get_combo_phy_dpll(struct intel_atomic_state *state,
icl_calc_dpll_state(dev_priv, &pll_params, &port_dpll->hw_state);
- if (IS_ROCKETLAKE(dev_priv)) {
+ if (IS_DG1(dev_priv)) {
+ if (port == PORT_D || port == PORT_E) {
+ dpll_mask =
+ BIT(DPLL_ID_DG1_DPLL2) |
+ BIT(DPLL_ID_DG1_DPLL3);
+ } else {
+ dpll_mask =
+ BIT(DPLL_ID_DG1_DPLL0) |
+ BIT(DPLL_ID_DG1_DPLL1);
+ }
+ } else if (IS_ROCKETLAKE(dev_priv)) {
dpll_mask =
BIT(DPLL_ID_EHL_DPLL4) |
BIT(DPLL_ID_ICL_DPLL1) |
BIT(DPLL_ID_ICL_DPLL0);
- } else if (IS_ELKHARTLAKE(dev_priv) && port != PORT_A) {
+ } else if (IS_JSL_EHL(dev_priv) && port != PORT_A) {
dpll_mask =
BIT(DPLL_ID_EHL_DPLL4) |
BIT(DPLL_ID_ICL_DPLL1) |
@@ -3820,7 +3865,10 @@ static bool icl_pll_get_hw_state(struct drm_i915_private *dev_priv,
if (!(val & PLL_ENABLE))
goto out;
- if (IS_ROCKETLAKE(dev_priv)) {
+ if (IS_DG1(dev_priv)) {
+ hw_state->cfgcr0 = intel_de_read(dev_priv, DG1_DPLL_CFGCR0(id));
+ hw_state->cfgcr1 = intel_de_read(dev_priv, DG1_DPLL_CFGCR1(id));
+ } else if (IS_ROCKETLAKE(dev_priv)) {
hw_state->cfgcr0 = intel_de_read(dev_priv,
RKL_DPLL_CFGCR0(id));
hw_state->cfgcr1 = intel_de_read(dev_priv,
@@ -3831,7 +3879,7 @@ static bool icl_pll_get_hw_state(struct drm_i915_private *dev_priv,
hw_state->cfgcr1 = intel_de_read(dev_priv,
TGL_DPLL_CFGCR1(id));
} else {
- if (IS_ELKHARTLAKE(dev_priv) && id == DPLL_ID_EHL_DPLL4) {
+ if (IS_JSL_EHL(dev_priv) && id == DPLL_ID_EHL_DPLL4) {
hw_state->cfgcr0 = intel_de_read(dev_priv,
ICL_DPLL_CFGCR0(4));
hw_state->cfgcr1 = intel_de_read(dev_priv,
@@ -3873,14 +3921,17 @@ static void icl_dpll_write(struct drm_i915_private *dev_priv,
const enum intel_dpll_id id = pll->info->id;
i915_reg_t cfgcr0_reg, cfgcr1_reg;
- if (IS_ROCKETLAKE(dev_priv)) {
+ if (IS_DG1(dev_priv)) {
+ cfgcr0_reg = DG1_DPLL_CFGCR0(id);
+ cfgcr1_reg = DG1_DPLL_CFGCR1(id);
+ } else if (IS_ROCKETLAKE(dev_priv)) {
cfgcr0_reg = RKL_DPLL_CFGCR0(id);
cfgcr1_reg = RKL_DPLL_CFGCR1(id);
} else if (INTEL_GEN(dev_priv) >= 12) {
cfgcr0_reg = TGL_DPLL_CFGCR0(id);
cfgcr1_reg = TGL_DPLL_CFGCR1(id);
} else {
- if (IS_ELKHARTLAKE(dev_priv) && id == DPLL_ID_EHL_DPLL4) {
+ if (IS_JSL_EHL(dev_priv) && id == DPLL_ID_EHL_DPLL4) {
cfgcr0_reg = ICL_DPLL_CFGCR0(4);
cfgcr1_reg = ICL_DPLL_CFGCR1(4);
} else {
@@ -4054,7 +4105,7 @@ static void combo_pll_enable(struct drm_i915_private *dev_priv,
{
i915_reg_t enable_reg = intel_combo_pll_enable_reg(dev_priv, pll);
- if (IS_ELKHARTLAKE(dev_priv) &&
+ if (IS_JSL_EHL(dev_priv) &&
pll->info->id == DPLL_ID_EHL_DPLL4) {
/*
@@ -4167,7 +4218,7 @@ static void combo_pll_disable(struct drm_i915_private *dev_priv,
icl_pll_disable(dev_priv, pll, enable_reg);
- if (IS_ELKHARTLAKE(dev_priv) &&
+ if (IS_JSL_EHL(dev_priv) &&
pll->info->id == DPLL_ID_EHL_DPLL4)
intel_display_power_put(dev_priv, POWER_DOMAIN_DPLL_DC_OFF,
pll->wakeref);
@@ -4317,6 +4368,22 @@ static const struct intel_dpll_mgr rkl_pll_mgr = {
.dump_hw_state = icl_dump_hw_state,
};
+static const struct dpll_info dg1_plls[] = {
+ { "DPLL 0", &combo_pll_funcs, DPLL_ID_DG1_DPLL0, 0 },
+ { "DPLL 1", &combo_pll_funcs, DPLL_ID_DG1_DPLL1, 0 },
+ { "DPLL 2", &combo_pll_funcs, DPLL_ID_DG1_DPLL2, 0 },
+ { "DPLL 3", &combo_pll_funcs, DPLL_ID_DG1_DPLL3, 0 },
+ { },
+};
+
+static const struct intel_dpll_mgr dg1_pll_mgr = {
+ .dpll_info = dg1_plls,
+ .get_dplls = icl_get_dplls,
+ .put_dplls = icl_put_dplls,
+ .update_ref_clks = icl_update_dpll_ref_clks,
+ .dump_hw_state = icl_dump_hw_state,
+};
+
/**
* intel_shared_dpll_init - Initialize shared DPLLs
* @dev: drm device
@@ -4330,11 +4397,13 @@ void intel_shared_dpll_init(struct drm_device *dev)
const struct dpll_info *dpll_info;
int i;
- if (IS_ROCKETLAKE(dev_priv))
+ if (IS_DG1(dev_priv))
+ dpll_mgr = &dg1_pll_mgr;
+ else if (IS_ROCKETLAKE(dev_priv))
dpll_mgr = &rkl_pll_mgr;
else if (INTEL_GEN(dev_priv) >= 12)
dpll_mgr = &tgl_pll_mgr;
- else if (IS_ELKHARTLAKE(dev_priv))
+ else if (IS_JSL_EHL(dev_priv))
dpll_mgr = &ehl_pll_mgr;
else if (INTEL_GEN(dev_priv) >= 11)
dpll_mgr = &icl_pll_mgr;
@@ -4456,16 +4525,33 @@ void intel_update_active_dpll(struct intel_atomic_state *state,
* intel_dpll_get_freq - calculate the DPLL's output frequency
* @i915: i915 device
* @pll: DPLL for which to calculate the output frequency
+ * @pll_state: DPLL state from which to calculate the output frequency
*
- * Return the output frequency corresponding to @pll's current state.
+ * Return the output frequency corresponding to @pll's passed in @pll_state.
*/
int intel_dpll_get_freq(struct drm_i915_private *i915,
- const struct intel_shared_dpll *pll)
+ const struct intel_shared_dpll *pll,
+ const struct intel_dpll_hw_state *pll_state)
{
if (drm_WARN_ON(&i915->drm, !pll->info->funcs->get_freq))
return 0;
- return pll->info->funcs->get_freq(i915, pll);
+ return pll->info->funcs->get_freq(i915, pll, pll_state);
+}
+
+/**
+ * intel_dpll_get_hw_state - readout the DPLL's hardware state
+ * @i915: i915 device
+ * @pll: DPLL for which to calculate the output frequency
+ * @hw_state: DPLL's hardware state
+ *
+ * Read out @pll's hardware state into @hw_state.
+ */
+bool intel_dpll_get_hw_state(struct drm_i915_private *i915,
+ struct intel_shared_dpll *pll,
+ struct intel_dpll_hw_state *hw_state)
+{
+ return pll->info->funcs->get_hw_state(i915, pll, hw_state);
}
static void readout_dpll_hw_state(struct drm_i915_private *i915,
@@ -4473,10 +4559,9 @@ static void readout_dpll_hw_state(struct drm_i915_private *i915,
{
struct intel_crtc *crtc;
- pll->on = pll->info->funcs->get_hw_state(i915, pll,
- &pll->state.hw_state);
+ pll->on = intel_dpll_get_hw_state(i915, pll, &pll->state.hw_state);
- if (IS_ELKHARTLAKE(i915) && pll->on &&
+ if (IS_JSL_EHL(i915) && pll->on &&
pll->info->id == DPLL_ID_EHL_DPLL4) {
pll->wakeref = intel_display_power_get(i915,
POWER_DOMAIN_DPLL_DC_OFF);
@@ -4531,7 +4616,7 @@ void intel_dpll_sanitize_state(struct drm_i915_private *i915)
}
/**
- * intel_shared_dpll_dump_hw_state - write hw_state to dmesg
+ * intel_dpll_dump_hw_state - write hw_state to dmesg
* @dev_priv: i915 drm device
* @hw_state: hw state to be written to the log
*