X-Git-Url: http://git.openwrt.org/?a=blobdiff_plain;f=target%2Flinux%2Fbrcm2708%2Fpatches-4.19%2F950-0538-drm-v3d-Clock-V3D-down-when-not-in-use.patch;fp=target%2Flinux%2Fbrcm2708%2Fpatches-4.19%2F950-0538-drm-v3d-Clock-V3D-down-when-not-in-use.patch;h=b4c2c3b5e260f46c00072042872b59d5ef7ebc2f;hb=c2308a7e4adbb2acc8ff149f91d1ca46801c135e;hp=0000000000000000000000000000000000000000;hpb=67dcc43f3a22dc3a7ac07a7065971b426feeb043;p=openwrt%2Fstaging%2Fchunkeey.git

diff --git a/target/linux/brcm2708/patches-4.19/950-0538-drm-v3d-Clock-V3D-down-when-not-in-use.patch b/target/linux/brcm2708/patches-4.19/950-0538-drm-v3d-Clock-V3D-down-when-not-in-use.patch
new file mode 100644
index 0000000000..b4c2c3b5e2
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.19/950-0538-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".