| /* |
| * |
| * (C) COPYRIGHT 2013-2015 ARM Limited. All rights reserved. |
| * |
| * This program is free software and is provided to you under the terms of the |
| * GNU General Public License version 2 as published by the Free Software |
| * Foundation, and any use by you of this program is subject to the terms |
| * of such GNU licence. |
| * |
| * A copy of the licence is included with the program, and can also be obtained |
| * from Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| * |
| */ |
| |
| /* |
| * A core availability policy implementing random core rotation. |
| * |
| * This policy periodically selects a new core mask at random. This new mask is |
| * applied in two stages. It initially powers off all undesired cores, by |
| * removing them from the core availability mask. Once it is confirmed that |
| * these cores are powered off, then the desired cores are powered on. |
| */ |
| |
| #include <mali_kbase.h> |
| #include <mali_kbase_pm.h> |
| #include <backend/gpu/mali_kbase_pm_internal.h> |
| #include <linux/random.h> |
| #include <linux/version.h> |
| |
| #if LINUX_VERSION_CODE < KERNEL_VERSION(3, 8, 0) |
| /* random32 was renamed to prandom_u32 in 3.8 */ |
| #define prandom_u32 random32 |
| #endif |
| |
| void random_timer_callback(unsigned long cb) |
| { |
| struct kbase_device *kbdev = (struct kbase_device *)cb; |
| struct kbasep_pm_ca_policy_random *data = |
| &kbdev->pm.backend.ca_policy_data.random; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&kbdev->pm.power_change_lock, flags); |
| |
| /* Select new core mask, ensuring that core group 0 is not powered off |
| */ |
| do { |
| data->cores_desired = prandom_u32() & |
| kbdev->gpu_props.props.raw_props.shader_present; |
| } while (!(data->cores_desired & |
| kbdev->gpu_props.props.coherency_info.group[0].core_mask)); |
| |
| /* Disable any cores that are now unwanted */ |
| data->cores_enabled &= data->cores_desired; |
| |
| kbdev->pm.backend.ca_in_transition = true; |
| |
| /* If there are no cores to be powered off then power on desired cores |
| */ |
| if (!(data->cores_used & ~data->cores_desired)) { |
| data->cores_enabled = data->cores_desired; |
| kbdev->pm.backend.ca_in_transition = false; |
| } |
| |
| data->core_change_timer.expires = jiffies + 5 * HZ; |
| |
| add_timer(&data->core_change_timer); |
| |
| kbase_pm_update_cores_state_nolock(kbdev); |
| |
| spin_unlock_irqrestore(&kbdev->pm.power_change_lock, flags); |
| |
| dev_info(kbdev->dev, "Random policy : new core mask=%llX %llX\n", |
| data->cores_desired, data->cores_enabled); |
| } |
| |
| KBASE_EXPORT_TEST_API(random_timer_callback); |
| |
| static void random_init(struct kbase_device *kbdev) |
| { |
| struct kbasep_pm_ca_policy_random *data = |
| &kbdev->pm.backend.ca_policy_data.random; |
| |
| data->cores_enabled = kbdev->gpu_props.props.raw_props.shader_present; |
| data->cores_desired = kbdev->gpu_props.props.raw_props.shader_present; |
| data->cores_used = 0; |
| kbdev->pm.backend.ca_in_transition = false; |
| |
| init_timer(&data->core_change_timer); |
| |
| data->core_change_timer.function = random_timer_callback; |
| data->core_change_timer.data = (unsigned long) kbdev; |
| data->core_change_timer.expires = jiffies + 5 * HZ; |
| |
| add_timer(&data->core_change_timer); |
| } |
| |
| static void random_term(struct kbase_device *kbdev) |
| { |
| struct kbasep_pm_ca_policy_random *data = |
| &kbdev->pm.backend.ca_policy_data.random; |
| |
| del_timer(&data->core_change_timer); |
| } |
| |
| static u64 random_get_core_mask(struct kbase_device *kbdev) |
| { |
| return kbdev->pm.backend.ca_policy_data.random.cores_enabled; |
| } |
| |
| static void random_update_core_status(struct kbase_device *kbdev, |
| u64 cores_ready, |
| u64 cores_transitioning) |
| { |
| struct kbasep_pm_ca_policy_random *data = |
| &kbdev->pm.backend.ca_policy_data.random; |
| |
| lockdep_assert_held(&kbdev->pm.power_change_lock); |
| |
| data->cores_used = cores_ready | cores_transitioning; |
| |
| /* If in desired state then clear transition flag */ |
| if (data->cores_enabled == data->cores_desired) |
| kbdev->pm.backend.ca_in_transition = false; |
| |
| /* If all undesired cores are now off then power on desired cores. |
| * The direct comparison against cores_enabled limits potential |
| * recursion to one level */ |
| if (!(data->cores_used & ~data->cores_desired) && |
| data->cores_enabled != data->cores_desired) { |
| data->cores_enabled = data->cores_desired; |
| |
| kbase_pm_update_cores_state_nolock(kbdev); |
| |
| kbdev->pm.backend.ca_in_transition = false; |
| } |
| } |
| |
| /* |
| * The struct kbase_pm_ca_policy structure for the random core availability |
| * policy. |
| * |
| * This is the static structure that defines the random core availability power |
| * policy's callback and name. |
| */ |
| const struct kbase_pm_ca_policy kbase_pm_ca_random_policy_ops = { |
| "random", /* name */ |
| random_init, /* init */ |
| random_term, /* term */ |
| random_get_core_mask, /* get_core_mask */ |
| random_update_core_status, /* update_core_status */ |
| 0u, /* flags */ |
| KBASE_PM_CA_POLICY_ID_RANDOM, /* id */ |
| }; |
| |
| KBASE_EXPORT_TEST_API(kbase_pm_ca_random_policy_ops); |