[PATCH] drm/rockchip: Don't use atomic constructs for psr

From: Sean Paul
Date: Tue Oct 18 2016 - 16:07:49 EST


Instead of using timer and spinlocks, use delayed_work and
mutexes for rockchip psr. This allows us to make blocking
calls when enabling/disabling psr (which is sort of important
given we're talking over dpcd to the display).

Cc: zain wang <wzz@xxxxxxxxxxxxxx>
Signed-off-by: Sean Paul <seanpaul@xxxxxxxxxxxx>
---
drivers/gpu/drm/rockchip/analogix_dp-rockchip.c | 14 +++--
drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 2 +-
drivers/gpu/drm/rockchip/rockchip_drm_drv.h | 2 +-
drivers/gpu/drm/rockchip/rockchip_drm_psr.c | 68 +++++++++++--------------
4 files changed, 37 insertions(+), 49 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
index e5471e7..8877ba2 100644
--- a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
+++ b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
@@ -72,7 +72,7 @@ struct rockchip_dp_device {
struct reset_control *rst;

struct work_struct psr_work;
- spinlock_t psr_lock;
+ struct mutex psr_lock;
unsigned int psr_state;

const struct rockchip_dp_chip_data *data;
@@ -83,21 +83,20 @@ struct rockchip_dp_device {
static void analogix_dp_psr_set(struct drm_encoder *encoder, bool enabled)
{
struct rockchip_dp_device *dp = to_dp(encoder);
- unsigned long flags;

if (!analogix_dp_psr_supported(dp->dev))
return;

dev_dbg(dp->dev, "%s PSR...\n", enabled ? "Entry" : "Exit");

- spin_lock_irqsave(&dp->psr_lock, flags);
+ mutex_lock(&dp->psr_lock);
if (enabled)
dp->psr_state = EDP_VSC_PSR_STATE_ACTIVE;
else
dp->psr_state = ~EDP_VSC_PSR_STATE_ACTIVE;

schedule_work(&dp->psr_work);
- spin_unlock_irqrestore(&dp->psr_lock, flags);
+ mutex_unlock(&dp->psr_lock);
}

static void analogix_dp_psr_work(struct work_struct *work)
@@ -108,7 +107,6 @@ static void analogix_dp_psr_work(struct work_struct *work)
int psr_state = dp->psr_state;
int vact_end;
int ret;
- unsigned long flags;

if (!crtc)
return;
@@ -122,12 +120,12 @@ static void analogix_dp_psr_work(struct work_struct *work)
return;
}

- spin_lock_irqsave(&dp->psr_lock, flags);
+ mutex_lock(&dp->psr_lock);
if (psr_state == EDP_VSC_PSR_STATE_ACTIVE)
analogix_dp_enable_psr(dp->dev);
else
analogix_dp_disable_psr(dp->dev);
- spin_unlock_irqrestore(&dp->psr_lock, flags);
+ mutex_unlock(&dp->psr_lock);
}

static int rockchip_dp_pre_init(struct rockchip_dp_device *dp)
@@ -401,7 +399,7 @@ static int rockchip_dp_bind(struct device *dev, struct device *master,
dp->plat_data.power_off = rockchip_dp_powerdown;
dp->plat_data.get_modes = rockchip_dp_get_modes;

- spin_lock_init(&dp->psr_lock);
+ mutex_init(&dp->psr_lock);
dp->psr_state = ~EDP_VSC_PSR_STATE_ACTIVE;
INIT_WORK(&dp->psr_work, analogix_dp_psr_work);

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
index 8c8cbe8..5afd5a1 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
@@ -157,7 +157,7 @@ static int rockchip_drm_bind(struct device *dev)
drm_dev->dev_private = private;

INIT_LIST_HEAD(&private->psr_list);
- spin_lock_init(&private->psr_list_lock);
+ mutex_init(&private->psr_list_lock);

drm_mode_config_init(drm_dev);

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
index fb6226c..095e178 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
@@ -62,7 +62,7 @@ struct rockchip_drm_private {
struct drm_atomic_state *state;

struct list_head psr_list;
- spinlock_t psr_list_lock;
+ struct mutex psr_list_lock;
};

int rockchip_register_crtc_funcs(struct drm_crtc *crtc,
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_psr.c b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c
index 4c379e9..eb49f38 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_psr.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c
@@ -18,7 +18,7 @@
#include "rockchip_drm_drv.h"
#include "rockchip_drm_psr.h"

-#define PSR_FLUSH_TIMEOUT msecs_to_jiffies(100)
+#define PSR_FLUSH_TIMEOUT_MS 100

enum psr_state {
PSR_FLUSH,
@@ -30,11 +30,11 @@ struct psr_drv {
struct list_head list;
struct drm_encoder *encoder;

- spinlock_t lock;
+ struct mutex lock;
bool active;
enum psr_state state;

- struct timer_list flush_timer;
+ struct delayed_work flush_work;

void (*set)(struct drm_encoder *encoder, bool enable);
};
@@ -43,9 +43,8 @@ static struct psr_drv *find_psr_by_crtc(struct drm_crtc *crtc)
{
struct rockchip_drm_private *drm_drv = crtc->dev->dev_private;
struct psr_drv *psr;
- unsigned long flags;

- spin_lock_irqsave(&drm_drv->psr_list_lock, flags);
+ mutex_lock(&drm_drv->psr_list_lock);
list_for_each_entry(psr, &drm_drv->psr_list, list) {
if (psr->encoder->crtc == crtc)
goto out;
@@ -53,7 +52,7 @@ static struct psr_drv *find_psr_by_crtc(struct drm_crtc *crtc)
psr = ERR_PTR(-ENODEV);

out:
- spin_unlock_irqrestore(&drm_drv->psr_list_lock, flags);
+ mutex_unlock(&drm_drv->psr_list_lock);
return psr;
}

@@ -61,9 +60,8 @@ static struct psr_drv *find_psr_by_encoder(struct drm_encoder *encoder)
{
struct rockchip_drm_private *drm_drv = encoder->dev->dev_private;
struct psr_drv *psr;
- unsigned long flags;

- spin_lock_irqsave(&drm_drv->psr_list_lock, flags);
+ mutex_lock(&drm_drv->psr_list_lock);
list_for_each_entry(psr, &drm_drv->psr_list, list) {
if (psr->encoder == encoder)
goto out;
@@ -71,7 +69,7 @@ static struct psr_drv *find_psr_by_encoder(struct drm_encoder *encoder)
psr = ERR_PTR(-ENODEV);

out:
- spin_unlock_irqrestore(&drm_drv->psr_list_lock, flags);
+ mutex_unlock(&drm_drv->psr_list_lock);
return psr;
}

@@ -112,23 +110,21 @@ static void psr_set_state_locked(struct psr_drv *psr, enum psr_state state)

static void psr_set_state(struct psr_drv *psr, enum psr_state state)
{
- unsigned long flags;
-
- spin_lock_irqsave(&psr->lock, flags);
+ mutex_lock(&psr->lock);
psr_set_state_locked(psr, state);
- spin_unlock_irqrestore(&psr->lock, flags);
+ mutex_unlock(&psr->lock);
}

-static void psr_flush_handler(unsigned long data)
+static void psr_flush_handler(struct work_struct *work)
{
- struct psr_drv *psr = (struct psr_drv *)data;
- unsigned long flags;
+ struct psr_drv *psr = container_of(to_delayed_work(work),
+ struct psr_drv, flush_work);

/* If the state has changed since we initiated the flush, do nothing */
- spin_lock_irqsave(&psr->lock, flags);
+ mutex_lock(&psr->lock);
if (psr->state == PSR_FLUSH)
psr_set_state_locked(psr, PSR_ENABLE);
- spin_unlock_irqrestore(&psr->lock, flags);
+ mutex_unlock(&psr->lock);
}

/**
@@ -141,14 +137,13 @@ static void psr_flush_handler(unsigned long data)
int rockchip_drm_psr_activate(struct drm_encoder *encoder)
{
struct psr_drv *psr = find_psr_by_encoder(encoder);
- unsigned long flags;

if (IS_ERR(psr))
return PTR_ERR(psr);

- spin_lock_irqsave(&psr->lock, flags);
+ mutex_lock(&psr->lock);
psr->active = true;
- spin_unlock_irqrestore(&psr->lock, flags);
+ mutex_unlock(&psr->lock);

return 0;
}
@@ -164,15 +159,14 @@ EXPORT_SYMBOL(rockchip_drm_psr_activate);
int rockchip_drm_psr_deactivate(struct drm_encoder *encoder)
{
struct psr_drv *psr = find_psr_by_encoder(encoder);
- unsigned long flags;

if (IS_ERR(psr))
return PTR_ERR(psr);

- spin_lock_irqsave(&psr->lock, flags);
+ mutex_lock(&psr->lock);
psr->active = false;
- spin_unlock_irqrestore(&psr->lock, flags);
- del_timer_sync(&psr->flush_timer);
+ mutex_unlock(&psr->lock);
+ cancel_delayed_work_sync(&psr->flush_work);

return 0;
}
@@ -180,8 +174,7 @@ EXPORT_SYMBOL(rockchip_drm_psr_deactivate);

static void rockchip_drm_do_flush(struct psr_drv *psr)
{
- mod_timer(&psr->flush_timer,
- round_jiffies_up(jiffies + PSR_FLUSH_TIMEOUT));
+ schedule_delayed_work(&psr->flush_work, PSR_FLUSH_TIMEOUT_MS);
psr_set_state(psr, PSR_FLUSH);
}

@@ -219,12 +212,11 @@ void rockchip_drm_psr_flush_all(struct drm_device *dev)
{
struct rockchip_drm_private *drm_drv = dev->dev_private;
struct psr_drv *psr;
- unsigned long flags;

- spin_lock_irqsave(&drm_drv->psr_list_lock, flags);
+ mutex_lock(&drm_drv->psr_list_lock);
list_for_each_entry(psr, &drm_drv->psr_list, list)
rockchip_drm_do_flush(psr);
- spin_unlock_irqrestore(&drm_drv->psr_list_lock, flags);
+ mutex_unlock(&drm_drv->psr_list_lock);
}
EXPORT_SYMBOL(rockchip_drm_psr_flush_all);

@@ -241,7 +233,6 @@ int rockchip_drm_psr_register(struct drm_encoder *encoder,
{
struct rockchip_drm_private *drm_drv = encoder->dev->dev_private;
struct psr_drv *psr;
- unsigned long flags;

if (!encoder || !psr_set)
return -EINVAL;
@@ -250,17 +241,17 @@ int rockchip_drm_psr_register(struct drm_encoder *encoder,
if (!psr)
return -ENOMEM;

- setup_timer(&psr->flush_timer, psr_flush_handler, (unsigned long)psr);
- spin_lock_init(&psr->lock);
+ INIT_DELAYED_WORK(&psr->flush_work, psr_flush_handler);
+ mutex_init(&psr->lock);

psr->active = true;
psr->state = PSR_DISABLE;
psr->encoder = encoder;
psr->set = psr_set;

- spin_lock_irqsave(&drm_drv->psr_list_lock, flags);
+ mutex_lock(&drm_drv->psr_list_lock);
list_add_tail(&psr->list, &drm_drv->psr_list);
- spin_unlock_irqrestore(&drm_drv->psr_list_lock, flags);
+ mutex_unlock(&drm_drv->psr_list_lock);

return 0;
}
@@ -278,16 +269,15 @@ void rockchip_drm_psr_unregister(struct drm_encoder *encoder)
{
struct rockchip_drm_private *drm_drv = encoder->dev->dev_private;
struct psr_drv *psr, *n;
- unsigned long flags;

- spin_lock_irqsave(&drm_drv->psr_list_lock, flags);
+ mutex_lock(&drm_drv->psr_list_lock);
list_for_each_entry_safe(psr, n, &drm_drv->psr_list, list) {
if (psr->encoder == encoder) {
- del_timer(&psr->flush_timer);
+ cancel_delayed_work_sync(&psr->flush_work);
list_del(&psr->list);
kfree(psr);
}
}
- spin_unlock_irqrestore(&drm_drv->psr_list_lock, flags);
+ mutex_unlock(&drm_drv->psr_list_lock);
}
EXPORT_SYMBOL(rockchip_drm_psr_unregister);
--
2.8.0.rc3.226.g39d4020