@@ -3348,6 +3348,13 @@ int num_ioctls;</synopsis>
!Idrivers/gpu/drm/i915/intel_bios.c
!Idrivers/gpu/drm/i915/intel_vbt_defs.h
</sect2>
+
+ <sect2>
+ <title>Display PLLs</title>
+!Pdrivers/gpu/drm/i915/intel_dpll_mgr.c Display PLLs
+!Idrivers/gpu/drm/i915/intel_dpll_mgr.c
+!Idrivers/gpu/drm/i915/intel_dpll_mgr.h
+ </sect2>
</sect1>
<sect1>
@@ -23,6 +23,33 @@
#include "intel_drv.h"
+/**
+ * DOC: Display PLLs
+ *
+ * Display PLLs used for driving outputs vary by platform. While some have
+ * per-pipe or per-encoder dedicated PLLs, others allow the use of any PLL
+ * from a pool. In the latter scenario, it is possible that multiple pipes
+ * share a PLL if their configurations match.
+ *
+ * This file provides an abstraction over display PLLs. The function
+ * intel_shared_dpll_init() initializes the PLLs for the given platform. The
+ * users of a PLL are tracked and that tracking is integrated with the atomic
+ * modest interface. During an atomic operation, a PLL can be requested for a
+ * given crtc and encoder configuration by calling intel_get_shared_dpll() and
+ * a previously used PLL can be released with intel_release_shared_dpll().
+ * Changes to the users are first staged in the atomic state, and then made
+ * effective by calling intel_shared_dpll_swap_state() during the atomic
+ * commit phase.
+ */
+
+/**
+ * intel_get_shared_dpll_by_id - get a DPLL given its id
+ * @dev_priv: i915 device instance
+ * @id: pll id
+ *
+ * Returns:
+ * A pointer to the DPLL with @id
+ */
struct intel_shared_dpll *
intel_get_shared_dpll_by_id(struct drm_i915_private *dev_priv,
enum intel_dpll_id id)
@@ -30,6 +57,14 @@ intel_get_shared_dpll_by_id(struct drm_i915_private *dev_priv,
return &dev_priv->shared_dplls[id];
}
+/**
+ * intel_get_shared_dpll_id - get the id of a DPLL
+ * @dev_priv: i915 device instance
+ * @pll: the DPLL
+ *
+ * Returns:
+ * The id of @pll
+ */
enum intel_dpll_id
intel_get_shared_dpll_id(struct drm_i915_private *dev_priv,
struct intel_shared_dpll *pll)
@@ -58,6 +93,13 @@ void assert_shared_dpll(struct drm_i915_private *dev_priv,
pll->name, onoff(state), onoff(cur_state));
}
+/**
+ * intel_prepare_shared_dpll - call a dpll's prepare hook
+ * @crtc: crtc which has a shared dpll
+ *
+ * This calls the PLL's prepare hook if it has one and if the PLL is not
+ * already enabled. The prepare hook is platform specific.
+ */
void intel_prepare_shared_dpll(struct intel_crtc *crtc)
{
struct drm_device *dev = crtc->base.dev;
@@ -80,12 +122,10 @@ void intel_prepare_shared_dpll(struct intel_crtc *crtc)
}
/**
- * intel_enable_shared_dpll - enable PCH PLL
- * @dev_priv: i915 private structure
- * @pipe: pipe PLL to enable
+ * intel_enable_shared_dpll - enable a crtc's shared DPLL
+ * @crtc: crtc which has a shared DPLL
*
- * The PCH PLL needs to be enabled before the PCH transcoder, since it
- * drives the transcoder clock.
+ * Enable the shared DPLL used by @crtc.
*/
void intel_enable_shared_dpll(struct intel_crtc *crtc)
{
@@ -126,6 +166,12 @@ out:
mutex_unlock(&dev_priv->dpll_lock);
}
+/**
+ * intel_disable_shared_dpll - disable a crtc's shared DPLL
+ * @crtc: crtc which has a shared DPLL
+ *
+ * Disable the shared DPLL used by @crtc.
+ */
void intel_disable_shared_dpll(struct intel_crtc *crtc)
{
struct drm_device *dev = crtc->base.dev;
@@ -228,6 +274,16 @@ intel_reference_shared_dpll(struct intel_shared_dpll *pll,
shared_dpll[pll->id].crtc_mask |= 1 << crtc->pipe;
}
+/**
+ * intel_shared_dpll_swap_state - make atomic DPLL configuration effective
+ * @state: atomic state
+ *
+ * This is the dpll version of drm_atomic_helper_swap_state() since the
+ * helper does not handle driver-specific global state.
+ *
+ * Note that this doesn't actually swap states, the dpll configutation in
+ * @state is left unchanged.
+ */
void intel_shared_dpll_swap_state(struct drm_atomic_state *state)
{
struct drm_i915_private *dev_priv = to_i915(state->dev);
@@ -1695,6 +1751,12 @@ static const struct intel_dpll_mgr bxt_pll_mgr = {
.get_dpll = bxt_get_dpll,
};
+/**
+ * intel_shared_dpll_init - Initialize shared DPLLs
+ * @dev: drm device
+ *
+ * Initialize shared DPLLs for @dev.
+ */
void intel_shared_dpll_init(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1738,6 +1800,21 @@ void intel_shared_dpll_init(struct drm_device *dev)
intel_ddi_pll_init(dev);
}
+/**
+ * intel_get_shared_dpll - get a shared DPLL for crtc and encoder combination
+ * @crtc: crtc
+ * @crtc_state: atomic state for @crtc
+ * @encoder: encoder
+ *
+ * Find an appropriate DPLL for the given crtc and encoder combination. A
+ * reference from the @crtc to the returned pll is registered in the atomic
+ * state. That configuration is made effective by calling
+ * intel_shared_dpll_swap_state(). The reference should be released by calling
+ * intel_release_shared_dpll().
+ *
+ * Returns:
+ * A shared DPLL to be used by @crtc and @encoder with the given @crtc_state.
+ */
struct intel_shared_dpll *
intel_get_shared_dpll(struct intel_crtc *crtc,
struct intel_crtc_state *crtc_state,
@@ -1758,6 +1835,9 @@ intel_get_shared_dpll(struct intel_crtc *crtc,
* @crtc: crtc
* @state: atomic state
*
+ * This function releases the reference from @crtc to @dpll from the
+ * atomic @state. The new configuration is made effective by calling
+ * intel_shared_dpll_swap_state().
*/
void intel_release_shared_dpll(struct intel_shared_dpll *dpll,
struct intel_crtc *crtc,
@@ -40,6 +40,9 @@ struct intel_encoder;
struct intel_shared_dpll;
struct intel_dpll_mgr;
+/**
+ * enum intel_dpll_id - possible DPLL ids
+ */
enum intel_dpll_id {
DPLL_ID_PRIVATE = -1, /* non-shared dpll in use */
/* real shared dpll ids must be >= 0 */
@@ -61,11 +64,6 @@ enum intel_dpll_id {
};
#define I915_NUM_PLLS 6
-/** Inform the state checker that the DPLL is kept enabled even if not
- * in use by any crtc.
- */
-#define INTEL_DPLL_ALWAYS_ON (1 << 0)
-
struct intel_dpll_hw_state {
/* i9xx, pch plls */
uint32_t dpll;
@@ -98,34 +96,99 @@ struct intel_shared_dpll_config {
struct intel_dpll_hw_state hw_state;
};
+/**
+ * intel_shared_dpll_funcs - platform specific hooks for managing DPLLs
+ */
struct intel_shared_dpll_funcs {
- /* The mode_set hook is optional and should be used together with the
- * intel_prepare_shared_dpll function. */
+ /**
+ * @prepare:
+ *
+ * Optional hook to perform operations prior to enabling the PLL.
+ * Called from intel_prepare_shared_dpll() function.
+ */
void (*prepare)(struct drm_i915_private *dev_priv,
struct intel_shared_dpll *pll);
+
+ /**
+ * @enable:
+ *
+ * Hook for enabling the pll, called from intel_enable_shared_dpll()
+ * if the pll is not already enabled.
+ */
void (*enable)(struct drm_i915_private *dev_priv,
struct intel_shared_dpll *pll);
+
+ /**
+ * @disable:
+ *
+ * Hook for disabling the pll, called from intel_disable_shared_dpll()
+ * only when it is safe to disable the pll, i.e., there are no more
+ * tracked users for it.
+ */
void (*disable)(struct drm_i915_private *dev_priv,
struct intel_shared_dpll *pll);
+
+ /**
+ * @get_hw_state
+ *
+ * Hook for reading the values currently programmed to the DPLL
+ * registers. This is used for initial hw state readout and state
+ * verification after a mode set.
+ */
bool (*get_hw_state)(struct drm_i915_private *dev_priv,
struct intel_shared_dpll *pll,
struct intel_dpll_hw_state *hw_state);
};
+/**
+ * struct intel_shared_dpll - display PLL with tracked state and users
+ */
struct intel_shared_dpll {
struct intel_shared_dpll_config config;
- unsigned active_mask; /* mask of active CRTCs (i.e. DPMS on) */
- bool on; /* is the PLL actually active? Disabled during modeset */
+ /**
+ * @active_mask: mask of active CRTCs (i.e. DPMS on)
+ */
+ unsigned active_mask;
+
+ /**
+ * @on: is the PLL actually active? Disabled during modeset
+ */
+ bool on;
+
+ /**
+ * @name: DPLL name; used for logging
+ */
const char *name;
- /* should match the index in the dev_priv->shared_dplls array */
+
+ /**
+ * @id: unique indentifier for this DPLL; should match the index in the
+ * dev_priv->shared_dplls array
+ */
enum intel_dpll_id id;
+ /**
+ * @funcs: platform specific hooks
+ */
struct intel_shared_dpll_funcs funcs;
+ /**
+ * @flags:
+ *
+ * accepted flags: INTEL_DPLL_ALWAYS_ON
+ */
uint32_t flags;
};
+/**
+ * INTEL_DPLL_ALWAYS_ON
+ *
+ * Inform the state checker that the DPLL is kept enabled even if not
+ * in use by any crtc.
+ */
+#define INTEL_DPLL_ALWAYS_ON (1 << 0)
+
+
#define SKL_DPLL0 0
#define SKL_DPLL1 1
#define SKL_DPLL2 2