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Diffstat (limited to 'target/linux/bcm27xx/patches-4.19/950-0536-drm-v3d-Clock-V3D-down-when-not-in-use.patch')
-rw-r--r--target/linux/bcm27xx/patches-4.19/950-0536-drm-v3d-Clock-V3D-down-when-not-in-use.patch157
1 files changed, 157 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-4.19/950-0536-drm-v3d-Clock-V3D-down-when-not-in-use.patch b/target/linux/bcm27xx/patches-4.19/950-0536-drm-v3d-Clock-V3D-down-when-not-in-use.patch
new file mode 100644
index 0000000000..b4c2c3b5e2
--- /dev/null
+++ b/target/linux/bcm27xx/patches-4.19/950-0536-drm-v3d-Clock-V3D-down-when-not-in-use.patch
@@ -0,0 +1,157 @@
+From 3e6b687bae81bdf5a430ffaa04aa04ee195a866c Mon Sep 17 00:00:00 2001
+From: Eric Anholt <eric@anholt.net>
+Date: Thu, 2 May 2019 13:22:53 -0700
+Subject: [PATCH] drm/v3d: Clock V3D down when not in use.
+
+My various attempts at re-enabling runtime PM have failed, so just
+crank the clock down when V3D is idle to reduce power consumption.
+
+Signed-off-by: Eric Anholt <eric@anholt.net>
+---
+ drivers/gpu/drm/v3d/v3d_drv.c | 18 +++++++++++++
+ drivers/gpu/drm/v3d/v3d_drv.h | 6 +++++
+ drivers/gpu/drm/v3d/v3d_gem.c | 49 +++++++++++++++++++++++++++++++++++
+ 3 files changed, 73 insertions(+)
+
+--- a/drivers/gpu/drm/v3d/v3d_drv.c
++++ b/drivers/gpu/drm/v3d/v3d_drv.c
+@@ -297,6 +297,21 @@ static int v3d_platform_drm_probe(struct
+ }
+ }
+
++ v3d->clk = devm_clk_get(dev, NULL);
++ if (IS_ERR(v3d->clk)) {
++ if (ret != -EPROBE_DEFER)
++ dev_err(dev, "Failed to get clock\n");
++ goto dev_free;
++ }
++ v3d->clk_up_rate = clk_get_rate(v3d->clk);
++ /* For downclocking, drop it to the minimum frequency we can get from
++ * the CPRMAN clock generator dividing off our parent. The divider is
++ * 4 bits, but ask for just higher than that so that rounding doesn't
++ * make cprman reject our rate.
++ */
++ v3d->clk_down_rate =
++ (clk_get_rate(clk_get_parent(v3d->clk)) / (1 << 4)) + 10000;
++
+ if (v3d->ver < 41) {
+ ret = map_regs(v3d, &v3d->gca_regs, "gca");
+ if (ret)
+@@ -331,6 +346,9 @@ static int v3d_platform_drm_probe(struct
+ if (ret)
+ goto irq_disable;
+
++ ret = clk_set_rate(v3d->clk, v3d->clk_down_rate);
++ WARN_ON_ONCE(ret != 0);
++
+ return 0;
+
+ irq_disable:
+--- a/drivers/gpu/drm/v3d/v3d_drv.h
++++ b/drivers/gpu/drm/v3d/v3d_drv.h
+@@ -45,6 +45,12 @@ struct v3d_dev {
+ void __iomem *bridge_regs;
+ void __iomem *gca_regs;
+ struct clk *clk;
++ struct delayed_work clk_down_work;
++ unsigned long clk_up_rate, clk_down_rate;
++ struct mutex clk_lock;
++ u32 clk_refcount;
++ bool clk_up;
++
+ struct reset_control *reset;
+
+ /* Virtual and DMA addresses of the single shared page table. */
+--- a/drivers/gpu/drm/v3d/v3d_gem.c
++++ b/drivers/gpu/drm/v3d/v3d_gem.c
+@@ -3,6 +3,7 @@
+
+ #include <drm/drmP.h>
+ #include <drm/drm_syncobj.h>
++#include <linux/clk.h>
+ #include <linux/module.h>
+ #include <linux/platform_device.h>
+ #include <linux/pm_runtime.h>
+@@ -17,6 +18,47 @@
+ #include "v3d_trace.h"
+
+ static void
++v3d_clock_down_work(struct work_struct *work)
++{
++ struct v3d_dev *v3d =
++ container_of(work, struct v3d_dev, clk_down_work.work);
++ int ret;
++
++ ret = clk_set_rate(v3d->clk, v3d->clk_down_rate);
++ v3d->clk_up = false;
++ WARN_ON_ONCE(ret != 0);
++}
++
++static void
++v3d_clock_up_get(struct v3d_dev *v3d)
++{
++ mutex_lock(&v3d->clk_lock);
++ if (v3d->clk_refcount++ == 0) {
++ cancel_delayed_work_sync(&v3d->clk_down_work);
++ if (!v3d->clk_up) {
++ int ret;
++
++ ret = clk_set_rate(v3d->clk, v3d->clk_up_rate);
++ WARN_ON_ONCE(ret != 0);
++ v3d->clk_up = true;
++ }
++ }
++ mutex_unlock(&v3d->clk_lock);
++}
++
++static void
++v3d_clock_up_put(struct v3d_dev *v3d)
++{
++ mutex_lock(&v3d->clk_lock);
++ if (--v3d->clk_refcount == 0) {
++ schedule_delayed_work(&v3d->clk_down_work,
++ msecs_to_jiffies(100));
++ }
++ mutex_unlock(&v3d->clk_lock);
++}
++
++
++static void
+ v3d_init_core(struct v3d_dev *v3d, int core)
+ {
+ /* Set OVRTMUOUT, which means that the texture sampler uniform
+@@ -490,6 +532,7 @@ static void
+ v3d_job_free(struct kref *ref)
+ {
+ struct v3d_job *job = container_of(ref, struct v3d_job, refcount);
++ struct v3d_dev *v3d = job->v3d;
+ int i;
+
+ for (i = 0; i < job->bo_count; i++) {
+@@ -505,6 +548,8 @@ v3d_job_free(struct kref *ref)
+ dma_fence_put(job->irq_fence);
+ dma_fence_put(job->done_fence);
+
++ v3d_clock_up_put(v3d);
++
+ kfree(job);
+ }
+
+@@ -596,6 +641,7 @@ v3d_job_init(struct v3d_dev *v3d, struct
+ if (ret)
+ return ret;
+
++ v3d_clock_up_get(v3d);
+ kref_init(&job->refcount);
+
+ return 0;
+@@ -963,6 +1009,9 @@ v3d_gem_init(struct drm_device *dev)
+ mutex_init(&v3d->sched_lock);
+ mutex_init(&v3d->cache_clean_lock);
+
++ mutex_init(&v3d->clk_lock);
++ INIT_DELAYED_WORK(&v3d->clk_down_work, v3d_clock_down_work);
++
+ /* Note: We don't allocate address 0. Various bits of HW
+ * treat 0 as special, such as the occlusion query counters
+ * where 0 means "disabled".