Re: [PATCH] pinctrl: cherryview: Use raw_spinlock for locking
On Mon, Aug 17, 2015 at 3:13 PM, Mika Westerberg wrote: > When running -rt kernel and an interrupt happens on a GPIO line controlled by > Intel Cherryview/Braswell pinctrl driver we get: > > BUG: sleeping function called from invalid context at > kernel/locking/rtmutex.c:917 > in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0 > Preemption disabled at:[] cpu_startup_entry+0x17f/0x480 > > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.1.5-rt5 #16 > ... > Call Trace: > [] dump_stack+0x4a/0x61 > [] ___might_sleep+0xe7/0x170 > [] rt_spin_lock+0x1f/0x50 > [] chv_gpio_irq_ack+0x3d/0xa0 > [] handle_edge_irq+0x75/0x180 > [] generic_handle_irq+0x27/0x40 > [] chv_gpio_irq_handler+0x7e/0x110 > [] handle_irq+0xaa/0x190 > ... > > This is because desc->lock is raw_spinlock and is held when chv_gpio_irq_ack() > is called by the genirq core. chv_gpio_irq_ack() in turn takes pctrl->lock > which in -rt is an rt-mutex causing might_sleep() rightfully to complain about > sleeping function called from invalid context. > > In order to keep -rt happy but at the same time make sure that register > accesses get serialized, convert the driver to use raw_spinlock instead. > > Suggested-by: Linus Walleij > Signed-off-by: Mika Westerberg Patch applied. Again splendid job here. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] pinctrl: cherryview: Use raw_spinlock for locking
On Mon, Aug 17, 2015 at 3:13 PM, Mika Westerberg mika.westerb...@linux.intel.com wrote: When running -rt kernel and an interrupt happens on a GPIO line controlled by Intel Cherryview/Braswell pinctrl driver we get: BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917 in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0 Preemption disabled at:[81092e9f] cpu_startup_entry+0x17f/0x480 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.1.5-rt5 #16 ... Call Trace: IRQ [816283c6] dump_stack+0x4a/0x61 [81077e17] ___might_sleep+0xe7/0x170 [8162d6cf] rt_spin_lock+0x1f/0x50 [812e52ed] chv_gpio_irq_ack+0x3d/0xa0 [810a72f5] handle_edge_irq+0x75/0x180 [810a3457] generic_handle_irq+0x27/0x40 [812e57de] chv_gpio_irq_handler+0x7e/0x110 [810050aa] handle_irq+0xaa/0x190 ... This is because desc-lock is raw_spinlock and is held when chv_gpio_irq_ack() is called by the genirq core. chv_gpio_irq_ack() in turn takes pctrl-lock which in -rt is an rt-mutex causing might_sleep() rightfully to complain about sleeping function called from invalid context. In order to keep -rt happy but at the same time make sure that register accesses get serialized, convert the driver to use raw_spinlock instead. Suggested-by: Linus Walleij linus.wall...@linaro.org Signed-off-by: Mika Westerberg mika.westerb...@linux.intel.com Patch applied. Again splendid job here. Yours, Linus Walleij -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH] pinctrl: cherryview: Use raw_spinlock for locking
When running -rt kernel and an interrupt happens on a GPIO line controlled by
Intel Cherryview/Braswell pinctrl driver we get:
BUG: sleeping function called from invalid context at
kernel/locking/rtmutex.c:917
in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0
Preemption disabled at:[] cpu_startup_entry+0x17f/0x480
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.1.5-rt5 #16
...
Call Trace:
[] dump_stack+0x4a/0x61
[] ___might_sleep+0xe7/0x170
[] rt_spin_lock+0x1f/0x50
[] chv_gpio_irq_ack+0x3d/0xa0
[] handle_edge_irq+0x75/0x180
[] generic_handle_irq+0x27/0x40
[] chv_gpio_irq_handler+0x7e/0x110
[] handle_irq+0xaa/0x190
...
This is because desc->lock is raw_spinlock and is held when chv_gpio_irq_ack()
is called by the genirq core. chv_gpio_irq_ack() in turn takes pctrl->lock
which in -rt is an rt-mutex causing might_sleep() rightfully to complain about
sleeping function called from invalid context.
In order to keep -rt happy but at the same time make sure that register
accesses get serialized, convert the driver to use raw_spinlock instead.
Suggested-by: Linus Walleij
Signed-off-by: Mika Westerberg
---
drivers/pinctrl/intel/pinctrl-cherryview.c | 70 +++---
1 file changed, 35 insertions(+), 35 deletions(-)
diff --git a/drivers/pinctrl/intel/pinctrl-cherryview.c
b/drivers/pinctrl/intel/pinctrl-cherryview.c
index eaaede70d4de..70b7b41e40a9 100644
--- a/drivers/pinctrl/intel/pinctrl-cherryview.c
+++ b/drivers/pinctrl/intel/pinctrl-cherryview.c
@@ -174,7 +174,7 @@ struct chv_pinctrl {
struct pinctrl_dev *pctldev;
struct gpio_chip chip;
void __iomem *regs;
- spinlock_t lock;
+ raw_spinlock_t lock;
unsigned intr_lines[16];
const struct chv_community *community;
u32 saved_intmask;
@@ -720,13 +720,13 @@ static void chv_pin_dbg_show(struct pinctrl_dev *pctldev,
struct seq_file *s,
u32 ctrl0, ctrl1;
bool locked;
- spin_lock_irqsave(>lock, flags);
+ raw_spin_lock_irqsave(>lock, flags);
ctrl0 = readl(chv_padreg(pctrl, offset, CHV_PADCTRL0));
ctrl1 = readl(chv_padreg(pctrl, offset, CHV_PADCTRL1));
locked = chv_pad_locked(pctrl, offset);
- spin_unlock_irqrestore(>lock, flags);
+ raw_spin_unlock_irqrestore(>lock, flags);
if (ctrl0 & CHV_PADCTRL0_GPIOEN) {
seq_puts(s, "GPIO ");
@@ -789,14 +789,14 @@ static int chv_pinmux_set_mux(struct pinctrl_dev
*pctldev, unsigned function,
grp = >community->groups[group];
- spin_lock_irqsave(>lock, flags);
+ raw_spin_lock_irqsave(>lock, flags);
/* Check first that the pad is not locked */
for (i = 0; i < grp->npins; i++) {
if (chv_pad_locked(pctrl, grp->pins[i])) {
dev_warn(pctrl->dev, "unable to set mode for locked pin
%u\n",
grp->pins[i]);
- spin_unlock_irqrestore(>lock, flags);
+ raw_spin_unlock_irqrestore(>lock, flags);
return -EBUSY;
}
}
@@ -839,7 +839,7 @@ static int chv_pinmux_set_mux(struct pinctrl_dev *pctldev,
unsigned function,
pin, altfunc->mode, altfunc->invert_oe ? "" : "not ");
}
- spin_unlock_irqrestore(>lock, flags);
+ raw_spin_unlock_irqrestore(>lock, flags);
return 0;
}
@@ -853,13 +853,13 @@ static int chv_gpio_request_enable(struct pinctrl_dev
*pctldev,
void __iomem *reg;
u32 value;
- spin_lock_irqsave(>lock, flags);
+ raw_spin_lock_irqsave(>lock, flags);
if (chv_pad_locked(pctrl, offset)) {
value = readl(chv_padreg(pctrl, offset, CHV_PADCTRL0));
if (!(value & CHV_PADCTRL0_GPIOEN)) {
/* Locked so cannot enable */
- spin_unlock_irqrestore(>lock, flags);
+ raw_spin_unlock_irqrestore(>lock, flags);
return -EBUSY;
}
} else {
@@ -899,7 +899,7 @@ static int chv_gpio_request_enable(struct pinctrl_dev
*pctldev,
chv_writel(value, reg);
}
- spin_unlock_irqrestore(>lock, flags);
+ raw_spin_unlock_irqrestore(>lock, flags);
return 0;
}
@@ -913,13 +913,13 @@ static void chv_gpio_disable_free(struct pinctrl_dev
*pctldev,
void __iomem *reg;
u32 value;
- spin_lock_irqsave(>lock, flags);
+ raw_spin_lock_irqsave(>lock, flags);
reg = chv_padreg(pctrl, offset, CHV_PADCTRL0);
value = readl(reg) & ~CHV_PADCTRL0_GPIOEN;
chv_writel(value, reg);
- spin_unlock_irqrestore(>lock, flags);
+ raw_spin_unlock_irqrestore(>lock, flags);
}
static int chv_gpio_set_direction(struct pinctrl_dev *pctldev,
@@ -931,7 +931,7 @@ static int chv_gpio_set_direction(struct pinctrl_dev
*pctldev,
unsigned long flags;
[PATCH] pinctrl: cherryview: Use raw_spinlock for locking
When running -rt kernel and an interrupt happens on a GPIO line controlled by
Intel Cherryview/Braswell pinctrl driver we get:
BUG: sleeping function called from invalid context at
kernel/locking/rtmutex.c:917
in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0
Preemption disabled at:[81092e9f] cpu_startup_entry+0x17f/0x480
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.1.5-rt5 #16
...
Call Trace:
IRQ [816283c6] dump_stack+0x4a/0x61
[81077e17] ___might_sleep+0xe7/0x170
[8162d6cf] rt_spin_lock+0x1f/0x50
[812e52ed] chv_gpio_irq_ack+0x3d/0xa0
[810a72f5] handle_edge_irq+0x75/0x180
[810a3457] generic_handle_irq+0x27/0x40
[812e57de] chv_gpio_irq_handler+0x7e/0x110
[810050aa] handle_irq+0xaa/0x190
...
This is because desc-lock is raw_spinlock and is held when chv_gpio_irq_ack()
is called by the genirq core. chv_gpio_irq_ack() in turn takes pctrl-lock
which in -rt is an rt-mutex causing might_sleep() rightfully to complain about
sleeping function called from invalid context.
In order to keep -rt happy but at the same time make sure that register
accesses get serialized, convert the driver to use raw_spinlock instead.
Suggested-by: Linus Walleij linus.wall...@linaro.org
Signed-off-by: Mika Westerberg mika.westerb...@linux.intel.com
---
drivers/pinctrl/intel/pinctrl-cherryview.c | 70 +++---
1 file changed, 35 insertions(+), 35 deletions(-)
diff --git a/drivers/pinctrl/intel/pinctrl-cherryview.c
b/drivers/pinctrl/intel/pinctrl-cherryview.c
index eaaede70d4de..70b7b41e40a9 100644
--- a/drivers/pinctrl/intel/pinctrl-cherryview.c
+++ b/drivers/pinctrl/intel/pinctrl-cherryview.c
@@ -174,7 +174,7 @@ struct chv_pinctrl {
struct pinctrl_dev *pctldev;
struct gpio_chip chip;
void __iomem *regs;
- spinlock_t lock;
+ raw_spinlock_t lock;
unsigned intr_lines[16];
const struct chv_community *community;
u32 saved_intmask;
@@ -720,13 +720,13 @@ static void chv_pin_dbg_show(struct pinctrl_dev *pctldev,
struct seq_file *s,
u32 ctrl0, ctrl1;
bool locked;
- spin_lock_irqsave(pctrl-lock, flags);
+ raw_spin_lock_irqsave(pctrl-lock, flags);
ctrl0 = readl(chv_padreg(pctrl, offset, CHV_PADCTRL0));
ctrl1 = readl(chv_padreg(pctrl, offset, CHV_PADCTRL1));
locked = chv_pad_locked(pctrl, offset);
- spin_unlock_irqrestore(pctrl-lock, flags);
+ raw_spin_unlock_irqrestore(pctrl-lock, flags);
if (ctrl0 CHV_PADCTRL0_GPIOEN) {
seq_puts(s, GPIO );
@@ -789,14 +789,14 @@ static int chv_pinmux_set_mux(struct pinctrl_dev
*pctldev, unsigned function,
grp = pctrl-community-groups[group];
- spin_lock_irqsave(pctrl-lock, flags);
+ raw_spin_lock_irqsave(pctrl-lock, flags);
/* Check first that the pad is not locked */
for (i = 0; i grp-npins; i++) {
if (chv_pad_locked(pctrl, grp-pins[i])) {
dev_warn(pctrl-dev, unable to set mode for locked pin
%u\n,
grp-pins[i]);
- spin_unlock_irqrestore(pctrl-lock, flags);
+ raw_spin_unlock_irqrestore(pctrl-lock, flags);
return -EBUSY;
}
}
@@ -839,7 +839,7 @@ static int chv_pinmux_set_mux(struct pinctrl_dev *pctldev,
unsigned function,
pin, altfunc-mode, altfunc-invert_oe ? : not );
}
- spin_unlock_irqrestore(pctrl-lock, flags);
+ raw_spin_unlock_irqrestore(pctrl-lock, flags);
return 0;
}
@@ -853,13 +853,13 @@ static int chv_gpio_request_enable(struct pinctrl_dev
*pctldev,
void __iomem *reg;
u32 value;
- spin_lock_irqsave(pctrl-lock, flags);
+ raw_spin_lock_irqsave(pctrl-lock, flags);
if (chv_pad_locked(pctrl, offset)) {
value = readl(chv_padreg(pctrl, offset, CHV_PADCTRL0));
if (!(value CHV_PADCTRL0_GPIOEN)) {
/* Locked so cannot enable */
- spin_unlock_irqrestore(pctrl-lock, flags);
+ raw_spin_unlock_irqrestore(pctrl-lock, flags);
return -EBUSY;
}
} else {
@@ -899,7 +899,7 @@ static int chv_gpio_request_enable(struct pinctrl_dev
*pctldev,
chv_writel(value, reg);
}
- spin_unlock_irqrestore(pctrl-lock, flags);
+ raw_spin_unlock_irqrestore(pctrl-lock, flags);
return 0;
}
@@ -913,13 +913,13 @@ static void chv_gpio_disable_free(struct pinctrl_dev
*pctldev,
void __iomem *reg;
u32 value;
- spin_lock_irqsave(pctrl-lock, flags);
+ raw_spin_lock_irqsave(pctrl-lock, flags);
reg = chv_padreg(pctrl, offset, CHV_PADCTRL0);
value = readl(reg) ~CHV_PADCTRL0_GPIOEN;
chv_writel(value, reg);
-
