Re: [PATCH 05/19] drm/i915: power domains: add power well ops

Jesse Barnes
2014-02-20T19:32:59Z

On Tue, 18 Feb 2014 00:02:06 +0200
Imre Deak <imre.deak@intel.com> wrote:

> Split the 'set' power well handler into an 'enable', 'disable' and
> 'sync_hw' handler. This maps more conveniently to higher level
> operations, for example it allows us to push the hsw package c8 handling
> into the corresponding hsw/bdw enable/disable handlers and the hsw BIOS
> hand-over setting into the hsw/bdw sync_hw handler.
>
> No functional change.
>
> Signed-off-by: Imre Deak <imre.deak@intel.com>
> ---
> drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++---
> drivers/gpu/drm/i915/intel_pm.c | 73 +++++++++++++++++++++++++++--------------
> 2 files changed, 80 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index de0c0e0..8c8635e 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1006,6 +1006,36 @@ struct intel_ilk_power_mgmt {
> struct drm_i915_gem_object *renderctx;
> };
>
> +struct drm_i915_private;
> +struct i915_power_well;
> +
> +struct i915_power_well_ops {
> + /*
> + * Synchronize the well's hw state to match the current sw state, for
> + * example enable/disable it based on the current refcount. Called
> + * during driver init and resume time, possibly after first calling
> + * the enable/disable handlers.
> + */
> + void (*sync_hw)(struct drm_i915_private *dev_priv,
> + struct i915_power_well *power_well);
> + /*
> + * Enable the well and resources that depend on it (for example
> + * interrupts located on the well). Called after the 0->1 refcount
> + * transition.
> + */
> + void (*enable)(struct drm_i915_private *dev_priv,
> + struct i915_power_well *power_well);
> + /*
> + * Disable the well and resources that depend on it. Called after
> + * the 1->0 refcount transition.
> + */
> + void (*disable)(struct drm_i915_private *dev_priv,
> + struct i915_power_well *power_well);
> + /* Returns the hw enabled state. */
> + bool (*is_enabled)(struct drm_i915_private *dev_priv,
> + struct i915_power_well *power_well);
> +};
> +
> /* Power well structure for haswell */
> struct i915_power_well {
> const char *name;
> @@ -1014,10 +1044,7 @@ struct i915_power_well {
> int count;
> unsigned long domains;
> void *data;
> - void (*set)(struct drm_i915_private *dev_priv, struct i915_power_well *power_well,
> - bool enable);
> - bool (*is_enabled)(struct drm_i915_private *dev_priv,
> - struct i915_power_well *power_well);
> + const struct i915_power_well_ops *ops;
> };
>
> struct i915_power_domains {
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 9a608f1..7866426 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -5203,7 +5203,7 @@ bool intel_display_power_enabled(struct drm_i915_private *dev_priv,
> if (power_well->always_on)
> continue;
>
> - if (!power_well->is_enabled(dev_priv, power_well)) {
> + if (!power_well->ops->is_enabled(dev_priv, power_well)) {
> is_enabled = false;
> break;
> }
> @@ -5305,6 +5305,33 @@ static void hsw_set_power_well(struct drm_i915_private *dev_priv,
> }
> }
>
> +static void hsw_power_well_sync_hw(struct drm_i915_private *dev_priv,
> + struct i915_power_well *power_well)
> +{
> + hsw_set_power_well(dev_priv, power_well, power_well->count > 0);
> +
> + /*
> + * We're taking over the BIOS, so clear any requests made by it since
> + * the driver is in charge now.
> + */
> + if (I915_READ(HSW_PWR_WELL_BIOS) & HSW_PWR_WELL_ENABLE_REQUEST)
> + I915_WRITE(HSW_PWR_WELL_BIOS, 0);
> +}
> +
> +static void hsw_power_well_enable(struct drm_i915_private *dev_priv,
> + struct i915_power_well *power_well)
> +{
> + hsw_disable_package_c8(dev_priv);
> + hsw_set_power_well(dev_priv, power_well, true);
> +}
> +
> +static void hsw_power_well_disable(struct drm_i915_private *dev_priv,
> + struct i915_power_well *power_well)
> +{
> + hsw_set_power_well(dev_priv, power_well, false);
> + hsw_enable_package_c8(dev_priv);
> +}
> +
> void intel_display_power_get(struct drm_i915_private *dev_priv,
> enum intel_display_power_domain domain)
> {
> @@ -5317,10 +5344,8 @@ void intel_display_power_get(struct drm_i915_private *dev_priv,
> mutex_lock(&power_domains->lock);
>
> for_each_power_well(i, power_well, BIT(domain), power_domains)
> - if (!power_well->count++ && power_well->set) {
> - hsw_disable_package_c8(dev_priv);
> - power_well->set(dev_priv, power_well, true);
> - }
> + if (!power_well->count++ && power_well->ops->enable)
> + power_well->ops->enable(dev_priv, power_well);
>
> power_domains->domain_use_count[domain]++;
>
> @@ -5344,11 +5369,9 @@ void intel_display_power_put(struct drm_i915_private *dev_priv,
> for_each_power_well_rev(i, power_well, BIT(domain), power_domains) {
> WARN_ON(!power_well->count);
>
> - if (!--power_well->count && power_well->set &&
> - i915.disable_power_well) {
> - power_well->set(dev_priv, power_well, false);
> - hsw_enable_package_c8(dev_priv);
> - }
> + if (!--power_well->count && power_well->ops->disable &&
> + i915.disable_power_well)
> + power_well->ops->disable(dev_priv, power_well);
> }
>
> mutex_unlock(&power_domains->lock);
> @@ -5401,25 +5424,35 @@ EXPORT_SYMBOL_GPL(i915_release_power_well);
> (POWER_DOMAIN_MASK & ~BDW_ALWAYS_ON_POWER_DOMAINS) | \
> BIT(POWER_DOMAIN_INIT))
>
> +static const struct i915_power_well_ops i9xx_always_on_power_well_ops = { };
> +
> static struct i915_power_well i9xx_always_on_power_well[] = {
> {
> .name = "always-on",
> .always_on = 1,
> .domains = POWER_DOMAIN_MASK,
> + .ops = &i9xx_always_on_power_well_ops,
> },
> };
>
> +static const struct i915_power_well_ops hsw_power_well_ops = {
> + .sync_hw = hsw_power_well_sync_hw,
> + .enable = hsw_power_well_enable,
> + .disable = hsw_power_well_disable,
> + .is_enabled = hsw_power_well_enabled,
> +};
> +
> static struct i915_power_well hsw_power_wells[] = {
> {
> .name = "always-on",
> .always_on = 1,
> .domains = HSW_ALWAYS_ON_POWER_DOMAINS,
> + .ops = &i9xx_always_on_power_well_ops,
> },
> {
> .name = "display",
> .domains = HSW_DISPLAY_POWER_DOMAINS,
> - .is_enabled = hsw_power_well_enabled,
> - .set = hsw_set_power_well,
> + .ops = &hsw_power_well_ops,
> },
> };
>
> @@ -5428,12 +5461,12 @@ static struct i915_power_well bdw_power_wells[] = {
> .name = "always-on",
> .always_on = 1,
> .domains = BDW_ALWAYS_ON_POWER_DOMAINS,
> + .ops = &i9xx_always_on_power_well_ops,
> },
> {
> .name = "display",
> .domains = BDW_DISPLAY_POWER_DOMAINS,
> - .is_enabled = hsw_power_well_enabled,
> - .set = hsw_set_power_well,
> + .ops = &hsw_power_well_ops,
> },
> };
>
> @@ -5478,8 +5511,8 @@ static void intel_power_domains_resume(struct drm_i915_private *dev_priv)
>
> mutex_lock(&power_domains->lock);
> for_each_power_well(i, power_well, POWER_DOMAIN_MASK, power_domains) {
> - if (power_well->set)
> - power_well->set(dev_priv, power_well, power_well->count > 0);
> + if (power_well->ops->sync_hw)
> + power_well->ops->sync_hw(dev_priv, power_well);
> }
> mutex_unlock(&power_domains->lock);
> }
> @@ -5495,14 +5528,6 @@ void intel_power_domains_init_hw(struct drm_i915_private *dev_priv)
> /* For now, we need the power well to be always enabled. */
> intel_display_set_init_power(dev_priv, true);
> intel_power_domains_resume(dev_priv);
> -
> - if (!(IS_HASWELL(dev_priv->dev) || IS_BROADWELL(dev_priv->dev)))
> - return;
> -
> - /* We're taking over the BIOS, so clear any requests made by it since
> - * the driver is in charge now. */
> - if (I915_READ(HSW_PWR_WELL_BIOS) & HSW_PWR_WELL_ENABLE_REQUEST)
> - I915_WRITE(HSW_PWR_WELL_BIOS, 0);
> }
>
> /* Disables PC8 so we can use the GMBUS and DP AUX interrupts. */

Looks good. Only nitpick might be to have no-op ops for the 9xx case
and get rid of the checks for whether the ops function exists. Going
forward that might force us to think about things a bit at least. But
that's really just a style issue, the rest looks like a good change and
pulls some of the HSW bits out of the generic routines.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>

--
Jesse Barnes, Intel Open Source Technology Center