Hi Barry, On 05/19/2015 01:41 AM, Barry Song wrote: > From: Wei Chen <wei.chen@xxxxxxx> > > Add hwspinlock support for the CSR atlas7 SoC. > > The Hardware Spinlock device on atlas7 provides hardware assistance > for synchronization between the multiple processors in the system > (dual Cortex-A7, CAN bus Cortex-M3 and audio DSP). > > Cc: Suman Anna <s-anna@xxxxxx> > Cc: Bjorn Andersson <bjorn@xxxxxxx> > Signed-off-by: Wei Chen <wei.chen@xxxxxxx> > Signed-off-by: Barry Song <Baohua.Song@xxxxxxx> > --- > -v3: > use #hwlock-cells and general hwspinlock dt-binding; > drop relax(); > drop num-spinlocks in dts; > re-order Kconfig and Makefile; > other codingstyle issues. > Thanks Suman, Bjorn and Ohad > > drivers/hwspinlock/Kconfig | 12 ++++ > drivers/hwspinlock/Makefile | 1 + > drivers/hwspinlock/sirf_hwspinlock.c | 135 +++++++++++++++++++++++++++++++++++ > 3 files changed, 148 insertions(+) > create mode 100644 drivers/hwspinlock/sirf_hwspinlock.c > > diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig > index b5b4f52..73a4016 100644 > --- a/drivers/hwspinlock/Kconfig > +++ b/drivers/hwspinlock/Kconfig > @@ -30,6 +30,18 @@ config HWSPINLOCK_QCOM > > If unsure, say N. > > +config HWSPINLOCK_SIRF > + tristate "SIRF Hardware Spinlock device" > + depends on ARCH_SIRF > + select HWSPINLOCK > + help > + Say y here to support the SIRF Hardware Spinlock device, which > + provides a synchronisation mechanism for the various processors > + on the SoC. > + > + It's safe to say n here if you're not interested in SIRF hardware > + spinlock or just want a bare minimum kernel. > + > config HSEM_U8500 > tristate "STE Hardware Semaphore functionality" > depends on ARCH_U8500 > diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile > index 68f95d9..6b59cb5a 100644 > --- a/drivers/hwspinlock/Makefile > +++ b/drivers/hwspinlock/Makefile > @@ -5,4 +5,5 @@ > obj-$(CONFIG_HWSPINLOCK) += hwspinlock_core.o > obj-$(CONFIG_HWSPINLOCK_OMAP) += omap_hwspinlock.o > obj-$(CONFIG_HWSPINLOCK_QCOM) += qcom_hwspinlock.o > +obj-$(CONFIG_HWSPINLOCK_SIRF) += sirf_hwspinlock.o > obj-$(CONFIG_HSEM_U8500) += u8500_hsem.o > diff --git a/drivers/hwspinlock/sirf_hwspinlock.c b/drivers/hwspinlock/sirf_hwspinlock.c > new file mode 100644 > index 0000000..e7e5ba6 > --- /dev/null > +++ b/drivers/hwspinlock/sirf_hwspinlock.c > @@ -0,0 +1,135 @@ > +/* > + * SIRF hardware spinlock driver > + * > + * Copyright (c) 2014 Cambridge Silicon Radio Limited, a CSR plc group company. Not sure on this, but 2015 is here and now.. > + * > + * Licensed under GPLv2. > + */ > + > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/device.h> > +#include <linux/io.h> > +#include <linux/pm_runtime.h> > +#include <linux/slab.h> > +#include <linux/spinlock.h> > +#include <linux/hwspinlock.h> > +#include <linux/platform_device.h> > +#include <linux/of.h> > +#include <linux/of_address.h> > + > +#include "hwspinlock_internal.h" > + > +struct sirf_hwspinlock { > + void __iomem *io_base; > + struct hwspinlock_device bank; > +}; > + > +/* Number of Hardware Spinlocks*/ > +#define HW_SPINLOCK_NUMBER 30 > + > +/* Hardware spinlock register offsets */ > +#define HW_SPINLOCK_BASE 0x404 > +#define HW_SPINLOCK_OFFSET(x) (HW_SPINLOCK_BASE + 0x4 * (x)) > + > +static int sirf_hwspinlock_trylock(struct hwspinlock *lock) > +{ > + void __iomem *lock_addr = lock->priv; > + > + /* attempt to acquire the lock by reading value == 1 from it */ > + return !!readl(lock_addr); > +} > + > +static void sirf_hwspinlock_unlock(struct hwspinlock *lock) > +{ > + void __iomem *lock_addr = lock->priv; > + > + /* release the lock by writing 0 to it */ > + writel(0, lock_addr); > +} > + > +static const struct hwspinlock_ops sirf_hwspinlock_ops = { > + .trylock = sirf_hwspinlock_trylock, > + .unlock = sirf_hwspinlock_unlock, > +}; > + > +static int sirf_hwspinlock_probe(struct platform_device *pdev) > +{ > + struct sirf_hwspinlock *hwspin; > + struct hwspinlock *hwlock; > + int idx, ret; > + > + if (!pdev->dev.of_node) > + return -ENODEV; > + > + hwspin = devm_kzalloc(&pdev->dev, sizeof(*hwspin) + > + sizeof(*hwlock) * HW_SPINLOCK_NUMBER, GFP_KERNEL); > + if (!hwspin) > + return -ENOMEM; > + > + /* retrieve io base */ > + hwspin->io_base = of_iomap(pdev->dev.of_node, 0); > + if (!hwspin->io_base) > + ret = -ENOMEM; You are missing the bail out here. > + > + for (idx = 0; idx < HW_SPINLOCK_NUMBER; idx++) { > + hwlock = &hwspin->bank.lock[idx]; > + hwlock->priv = hwspin->io_base + HW_SPINLOCK_OFFSET(idx); > + } > + > + platform_set_drvdata(pdev, hwspin); > + > + pm_runtime_enable(&pdev->dev); > + > + ret = hwspin_lock_register(&hwspin->bank, &pdev->dev, > + &sirf_hwspinlock_ops, 0, HW_SPINLOCK_NUMBER); this is a checkpatch warning with the --strict option, not sure what convention Ohad is following though. Rest looks good. regards Suman -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html