/*
 * Copyright © 2006-2016 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

#include "intel_drv.h"

struct intel_shared_dpll *
intel_crtc_to_shared_dpll(struct intel_crtc *crtc)
{
	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;

	if (crtc->config->shared_dpll < 0)
		return NULL;

	return &dev_priv->shared_dplls[crtc->config->shared_dpll];
}

/* For ILK+ */
void assert_shared_dpll(struct drm_i915_private *dev_priv,
			struct intel_shared_dpll *pll,
			bool state)
{
	bool cur_state;
	struct intel_dpll_hw_state hw_state;

	if (WARN(!pll, "asserting DPLL %s with no DPLL\n", onoff(state)))
		return;

	cur_state = pll->get_hw_state(dev_priv, pll, &hw_state);
	I915_STATE_WARN(cur_state != state,
	     "%s assertion failure (expected %s, current %s)\n",
			pll->name, onoff(state), onoff(cur_state));
}

void intel_prepare_shared_dpll(struct intel_crtc *crtc)
{
	struct drm_device *dev = crtc->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_shared_dpll *pll = intel_crtc_to_shared_dpll(crtc);

	if (WARN_ON(pll == NULL))
		return;

	WARN_ON(!pll->config.crtc_mask);
	if (pll->active == 0) {
		DRM_DEBUG_DRIVER("setting up %s\n", pll->name);
		WARN_ON(pll->on);
		assert_shared_dpll_disabled(dev_priv, pll);

		pll->mode_set(dev_priv, pll);
	}
}

/**
 * intel_enable_shared_dpll - enable PCH PLL
 * @dev_priv: i915 private structure
 * @pipe: pipe PLL to enable
 *
 * The PCH PLL needs to be enabled before the PCH transcoder, since it
 * drives the transcoder clock.
 */
void intel_enable_shared_dpll(struct intel_crtc *crtc)
{
	struct drm_device *dev = crtc->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_shared_dpll *pll = intel_crtc_to_shared_dpll(crtc);

	if (WARN_ON(pll == NULL))
		return;

	if (WARN_ON(pll->config.crtc_mask == 0))
		return;

	DRM_DEBUG_KMS("enable %s (active %d, on? %d) for crtc %d\n",
		      pll->name, pll->active, pll->on,
		      crtc->base.base.id);

	if (pll->active++) {
		WARN_ON(!pll->on);
		assert_shared_dpll_enabled(dev_priv, pll);
		return;
	}
	WARN_ON(pll->on);

	intel_display_power_get(dev_priv, POWER_DOMAIN_PLLS);

	DRM_DEBUG_KMS("enabling %s\n", pll->name);
	pll->enable(dev_priv, pll);
	pll->on = true;
}

void intel_disable_shared_dpll(struct intel_crtc *crtc)
{
	struct drm_device *dev = crtc->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_shared_dpll *pll = intel_crtc_to_shared_dpll(crtc);

	/* PCH only available on ILK+ */
	if (INTEL_INFO(dev)->gen < 5)
		return;

	if (pll == NULL)
		return;

	if (WARN_ON(!(pll->config.crtc_mask & (1 << drm_crtc_index(&crtc->base)))))
		return;

	DRM_DEBUG_KMS("disable %s (active %d, on? %d) for crtc %d\n",
		      pll->name, pll->active, pll->on,
		      crtc->base.base.id);

	if (WARN_ON(pll->active == 0)) {
		assert_shared_dpll_disabled(dev_priv, pll);
		return;
	}

	assert_shared_dpll_enabled(dev_priv, pll);
	WARN_ON(!pll->on);
	if (--pll->active)
		return;

	DRM_DEBUG_KMS("disabling %s\n", pll->name);
	pll->disable(dev_priv, pll);
	pll->on = false;

	intel_display_power_put(dev_priv, POWER_DOMAIN_PLLS);
}

struct intel_shared_dpll *intel_get_shared_dpll(struct intel_crtc *crtc,
						struct intel_crtc_state *crtc_state)
{
	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
	struct intel_shared_dpll *pll;
	struct intel_shared_dpll_config *shared_dpll;
	enum intel_dpll_id i;
	int max = dev_priv->num_shared_dpll;

	shared_dpll = intel_atomic_get_shared_dpll_state(crtc_state->base.state);

	if (HAS_PCH_IBX(dev_priv->dev)) {
		/* Ironlake PCH has a fixed PLL->PCH pipe mapping. */
		i = (enum intel_dpll_id) crtc->pipe;
		pll = &dev_priv->shared_dplls[i];

		DRM_DEBUG_KMS("CRTC:%d using pre-allocated %s\n",
			      crtc->base.base.id, pll->name);

		WARN_ON(shared_dpll[i].crtc_mask);

		goto found;
	}

	if (IS_BROXTON(dev_priv->dev)) {
		/* PLL is attached to port in bxt */
		struct intel_encoder *encoder;
		struct intel_digital_port *intel_dig_port;

		encoder = intel_ddi_get_crtc_new_encoder(crtc_state);
		if (WARN_ON(!encoder))
			return NULL;

		intel_dig_port = enc_to_dig_port(&encoder->base);
		/* 1:1 mapping between ports and PLLs */
		i = (enum intel_dpll_id)intel_dig_port->port;
		pll = &dev_priv->shared_dplls[i];
		DRM_DEBUG_KMS("CRTC:%d using pre-allocated %s\n",
			crtc->base.base.id, pll->name);
		WARN_ON(shared_dpll[i].crtc_mask);

		goto found;
	} else if (INTEL_INFO(dev_priv)->gen < 9 && HAS_DDI(dev_priv))
		/* Do not consider SPLL */
		max = 2;

	for (i = 0; i < max; i++) {
		pll = &dev_priv->shared_dplls[i];

		/* Only want to check enabled timings first */
		if (shared_dpll[i].crtc_mask == 0)
			continue;

		if (memcmp(&crtc_state->dpll_hw_state,
			   &shared_dpll[i].hw_state,
			   sizeof(crtc_state->dpll_hw_state)) == 0) {
			DRM_DEBUG_KMS("CRTC:%d sharing existing %s (crtc mask 0x%08x, ative %d)\n",
				      crtc->base.base.id, pll->name,
				      shared_dpll[i].crtc_mask,
				      pll->active);
			goto found;
		}
	}

	/* Ok no matching timings, maybe there's a free one? */
	for (i = 0; i < dev_priv->num_shared_dpll; i++) {
		pll = &dev_priv->shared_dplls[i];
		if (shared_dpll[i].crtc_mask == 0) {
			DRM_DEBUG_KMS("CRTC:%d allocated %s\n",
				      crtc->base.base.id, pll->name);
			goto found;
		}
	}

	return NULL;

found:
	if (shared_dpll[i].crtc_mask == 0)
		shared_dpll[i].hw_state =
			crtc_state->dpll_hw_state;

	crtc_state->shared_dpll = i;
	DRM_DEBUG_DRIVER("using %s for pipe %c\n", pll->name,
			 pipe_name(crtc->pipe));

	shared_dpll[i].crtc_mask |= 1 << crtc->pipe;

	return pll;
}

void intel_shared_dpll_commit(struct drm_atomic_state *state)
{
	struct drm_i915_private *dev_priv = to_i915(state->dev);
	struct intel_shared_dpll_config *shared_dpll;
	struct intel_shared_dpll *pll;
	enum intel_dpll_id i;

	if (!to_intel_atomic_state(state)->dpll_set)
		return;

	shared_dpll = to_intel_atomic_state(state)->shared_dpll;
	for (i = 0; i < dev_priv->num_shared_dpll; i++) {
		pll = &dev_priv->shared_dplls[i];
		pll->config = shared_dpll[i];
	}
}

static bool ibx_pch_dpll_get_hw_state(struct drm_i915_private *dev_priv,
				      struct intel_shared_dpll *pll,
				      struct intel_dpll_hw_state *hw_state)
{
	uint32_t val;

	if (!intel_display_power_get_if_enabled(dev_priv, POWER_DOMAIN_PLLS))
		return false;

	val = I915_READ(PCH_DPLL(pll->id));
	hw_state->dpll = val;
	hw_state->fp0 = I915_READ(PCH_FP0(pll->id));
	hw_state->fp1 = I915_READ(PCH_FP1(pll->id));

	intel_display_power_put(dev_priv, POWER_DOMAIN_PLLS);

	return val & DPLL_VCO_ENABLE;
}

static void ibx_pch_dpll_mode_set(struct drm_i915_private *dev_priv,
				  struct intel_shared_dpll *pll)
{
	I915_WRITE(PCH_FP0(pll->id), pll->config.hw_state.fp0);
	I915_WRITE(PCH_FP1(pll->id), pll->config.hw_state.fp1);
}

static void ibx_assert_pch_refclk_enabled(struct drm_i915_private *dev_priv)
{
	u32 val;
	bool enabled;

	I915_STATE_WARN_ON(!(HAS_PCH_IBX(dev_priv->dev) || HAS_PCH_CPT(dev_priv->dev)));

	val = I915_READ(PCH_DREF_CONTROL);
	enabled = !!(val & (DREF_SSC_SOURCE_MASK | DREF_NONSPREAD_SOURCE_MASK |
			    DREF_SUPERSPREAD_SOURCE_MASK));
	I915_STATE_WARN(!enabled, "PCH refclk assertion failure, should be active but is disabled\n");
}

static void ibx_pch_dpll_enable(struct drm_i915_private *dev_priv,
				struct intel_shared_dpll *pll)
{
	/* PCH refclock must be enabled first */
	ibx_assert_pch_refclk_enabled(dev_priv);

	I915_WRITE(PCH_DPLL(pll->id), pll->config.hw_state.dpll);

	/* Wait for the clocks to stabilize. */
	POSTING_READ(PCH_DPLL(pll->id));
	udelay(150);

	/* The pixel multiplier can only be updated once the
	 * DPLL is enabled and the clocks are stable.
	 *
	 * So write it again.
	 */
	I915_WRITE(PCH_DPLL(pll->id), pll->config.hw_state.dpll);
	POSTING_READ(PCH_DPLL(pll->id));
	udelay(200);
}

static void ibx_pch_dpll_disable(struct drm_i915_private *dev_priv,
				 struct intel_shared_dpll *pll)
{
	struct drm_device *dev = dev_priv->dev;
	struct intel_crtc *crtc;

	/* Make sure no transcoder isn't still depending on us. */
	for_each_intel_crtc(dev, crtc) {
		if (intel_crtc_to_shared_dpll(crtc) == pll)
			assert_pch_transcoder_disabled(dev_priv, crtc->pipe);
	}

	I915_WRITE(PCH_DPLL(pll->id), 0);
	POSTING_READ(PCH_DPLL(pll->id));
	udelay(200);
}

static char *ibx_pch_dpll_names[] = {
	"PCH DPLL A",
	"PCH DPLL B",
};

static void ibx_pch_dpll_init(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int i;

	dev_priv->num_shared_dpll = 2;

	for (i = 0; i < dev_priv->num_shared_dpll; i++) {
		dev_priv->shared_dplls[i].id = i;
		dev_priv->shared_dplls[i].name = ibx_pch_dpll_names[i];
		dev_priv->shared_dplls[i].mode_set = ibx_pch_dpll_mode_set;
		dev_priv->shared_dplls[i].enable = ibx_pch_dpll_enable;
		dev_priv->shared_dplls[i].disable = ibx_pch_dpll_disable;
		dev_priv->shared_dplls[i].get_hw_state =
			ibx_pch_dpll_get_hw_state;
	}
}

void intel_shared_dpll_init(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (HAS_DDI(dev))
		intel_ddi_pll_init(dev);
	else if (HAS_PCH_IBX(dev) || HAS_PCH_CPT(dev))
		ibx_pch_dpll_init(dev);
	else
		dev_priv->num_shared_dpll = 0;

	BUG_ON(dev_priv->num_shared_dpll > I915_NUM_PLLS);
}