* [PATCH 0/2] hwrng: meson: add clock handling
@ 2017-02-19 20:30 Heiner Kallweit
2017-02-19 20:33 ` [PATCH 1/2] hwrng: meson: expose RNG0 clock via DT Heiner Kallweit
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Heiner Kallweit @ 2017-02-19 20:30 UTC (permalink / raw)
To: linus-amlogic
The HW randon number generator requires a clock and we shouldn't rely
on the boot loader to enable it.
Heiner Kallweit (2):
hwrng: meson: expose RNG0 clock via DT
hwrng: meson: add clock handling to driver
arch/arm64/boot/dts/amlogic/meson-gx.dtsi | 2 +-
arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi | 5 +++++
drivers/char/hw_random/meson-rng.c | 27 ++++++++++++++++++++++++++-
include/dt-bindings/clock/gxbb-clkc.h | 1 +
4 files changed, 33 insertions(+), 2 deletions(-)
--
2.11.1
^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH 1/2] hwrng: meson: expose RNG0 clock via DT 2017-02-19 20:30 [PATCH 0/2] hwrng: meson: add clock handling Heiner Kallweit @ 2017-02-19 20:33 ` Heiner Kallweit 2017-02-20 10:07 ` Jerome Brunet 2017-02-19 20:35 ` [PATCH 2/2] hwrng: meson: add clock handling to driver Heiner Kallweit 2017-02-21 1:58 ` [PATCH 0/2] hwrng: meson: add clock handling Neil Armstrong 2 siblings, 1 reply; 6+ messages in thread From: Heiner Kallweit @ 2017-02-19 20:33 UTC (permalink / raw) To: linus-amlogic Expose the RNG0 clock via DT. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- arch/arm64/boot/dts/amlogic/meson-gx.dtsi | 2 +- arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi | 5 +++++ include/dt-bindings/clock/gxbb-clkc.h | 1 + 3 files changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi index 5d995f77..620495a4 100644 --- a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi +++ b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi @@ -380,7 +380,7 @@ #size-cells = <2>; ranges = <0x0 0x0 0x0 0xc8834000 0x0 0x2000>; - rng { + hwrng: rng { compatible = "amlogic,meson-rng"; reg = <0x0 0x0 0x0 0x4>; }; diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi index 04b3324b..a375cb21 100644 --- a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi +++ b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi @@ -524,3 +524,8 @@ &vpu { compatible = "amlogic,meson-gxbb-vpu", "amlogic,meson-gx-vpu"; }; + +&hwrng { + clocks = <&clkc CLKID_RNG0>; + clock-names = "core"; +}; diff --git a/include/dt-bindings/clock/gxbb-clkc.h b/include/dt-bindings/clock/gxbb-clkc.h index 692846c7..473676b1 100644 --- a/include/dt-bindings/clock/gxbb-clkc.h +++ b/include/dt-bindings/clock/gxbb-clkc.h @@ -15,6 +15,7 @@ #define CLKID_SPI 34 #define CLKID_I2C 22 #define CLKID_SAR_ADC 23 +#define CLKID_RNG0 25 #define CLKID_ETH 36 #define CLKID_USB0 50 #define CLKID_USB1 51 -- 2.11.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 1/2] hwrng: meson: expose RNG0 clock via DT 2017-02-19 20:33 ` [PATCH 1/2] hwrng: meson: expose RNG0 clock via DT Heiner Kallweit @ 2017-02-20 10:07 ` Jerome Brunet 0 siblings, 0 replies; 6+ messages in thread From: Jerome Brunet @ 2017-02-20 10:07 UTC (permalink / raw) To: linus-amlogic On Sun, 2017-02-19 at 21:33 +0100, Heiner Kallweit wrote: > Expose the RNG0 clock via DT. > > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> > --- > ?arch/arm64/boot/dts/amlogic/meson-gx.dtsi???| 2 +- > ?arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi | 5 +++++ > ?include/dt-bindings/clock/gxbb-clkc.h???????| 1 + > ?3 files changed, 7 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi > b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi > index 5d995f77..620495a4 100644 > --- a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi > +++ b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi > @@ -380,7 +380,7 @@ > ? #size-cells = <2>; > ? ranges = <0x0 0x0 0x0 0xc8834000 0x0 > 0x2000>; > ? > - rng { > + hwrng: rng { > ? compatible = "amlogic,meson-rng"; > ? reg = <0x0 0x0 0x0 0x4>; > ? }; > diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi > b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi > index 04b3324b..a375cb21 100644 > --- a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi > +++ b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi > @@ -524,3 +524,8 @@ > ?&vpu { > ? compatible = "amlogic,meson-gxbb-vpu", "amlogic,meson-gx- > vpu"; > ?}; > + > +&hwrng { > + clocks = <&clkc CLKID_RNG0>; > + clock-names = "core"; > +}; > diff --git a/include/dt-bindings/clock/gxbb-clkc.h b/include/dt- > bindings/clock/gxbb-clkc.h > index 692846c7..473676b1 100644 > --- a/include/dt-bindings/clock/gxbb-clkc.h > +++ b/include/dt-bindings/clock/gxbb-clkc.h > @@ -15,6 +15,7 @@ > ?#define CLKID_SPI 34 > ?#define CLKID_I2C 22 > ?#define CLKID_SAR_ADC 23 > +#define CLKID_RNG0 25 Shouldn't you comment out the corresponding "define" in drivers/clk/meson/gxbb.h ? I don't know if it is rule, but we usually "expose" the clock (moving the define from drivers/clk/meson/gxbb.h to include/dt- bindings/clock/gxbb-clkc.h) in a dedicated patch, with the subject starting with "clk: gxbb: expose foobar clock". It helps the maintainers of the subsystem to give their ack. For this to happen, please remember the patch should be sent to them as well. Here you are missing the clock and dt guys: * Stephen Boyd <sboyd@codeaurora.org> * Michael Turquette <mturquette@baylibre.com> * linux-clk at vger.kernel.org * devicetree at vger.kernel.org scripts/get_maintainer.pl can help you finding all people your patch should be sent to. The remaining part of this patch involves DT, so the subject should start with "ARM64: dts: meson-gx:" You also need to add devicetree at vger.kernel.org in CC. Apart from these minor remarks, the patchset looks good to me. Thx ! > ?#define CLKID_ETH 36 > ?#define CLKID_USB0 50 > ?#define CLKID_USB1 51 ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 2/2] hwrng: meson: add clock handling to driver 2017-02-19 20:30 [PATCH 0/2] hwrng: meson: add clock handling Heiner Kallweit 2017-02-19 20:33 ` [PATCH 1/2] hwrng: meson: expose RNG0 clock via DT Heiner Kallweit @ 2017-02-19 20:35 ` Heiner Kallweit 2017-02-20 11:37 ` PrasannaKumar Muralidharan 2017-02-21 1:58 ` [PATCH 0/2] hwrng: meson: add clock handling Neil Armstrong 2 siblings, 1 reply; 6+ messages in thread From: Heiner Kallweit @ 2017-02-19 20:35 UTC (permalink / raw) To: linus-amlogic Add handling of RNG0 clock to the driver. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- drivers/char/hw_random/meson-rng.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/drivers/char/hw_random/meson-rng.c b/drivers/char/hw_random/meson-rng.c index 119d6984..1f586e48 100644 --- a/drivers/char/hw_random/meson-rng.c +++ b/drivers/char/hw_random/meson-rng.c @@ -62,6 +62,7 @@ #include <linux/slab.h> #include <linux/types.h> #include <linux/of.h> +#include <linux/clk.h> #define RNG_DATA 0x00 @@ -69,6 +70,7 @@ struct meson_rng_data { void __iomem *base; struct platform_device *pdev; struct hwrng rng; + struct clk *core_clk; }; static int meson_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait) @@ -86,6 +88,7 @@ static int meson_rng_probe(struct platform_device *pdev) struct device *dev = &pdev->dev; struct meson_rng_data *data; struct resource *res; + int ret; data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); if (!data) @@ -98,12 +101,33 @@ static int meson_rng_probe(struct platform_device *pdev) if (IS_ERR(data->base)) return PTR_ERR(data->base); + data->core_clk = devm_clk_get(dev, "core"); + if (IS_ERR(data->core_clk)) + return PTR_ERR(data->core_clk); + + ret = clk_prepare_enable(data->core_clk); + if (ret) + return ret; + data->rng.name = pdev->name; data->rng.read = meson_rng_read; platform_set_drvdata(pdev, data); - return devm_hwrng_register(dev, &data->rng); + ret = devm_hwrng_register(dev, &data->rng); + if (ret) + clk_disable_unprepare(data->core_clk); + + return ret; +} + +static int meson_rng_remove(struct platform_device *pdev) +{ + struct meson_rng_data *data = platform_get_drvdata(pdev); + + clk_disable_unprepare(data->core_clk); + + return 0; } static const struct of_device_id meson_rng_of_match[] = { @@ -114,6 +138,7 @@ MODULE_DEVICE_TABLE(of, meson_rng_of_match); static struct platform_driver meson_rng_driver = { .probe = meson_rng_probe, + .remove = meson_rng_remove, .driver = { .name = "meson-rng", .of_match_table = meson_rng_of_match, -- 2.11.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/2] hwrng: meson: add clock handling to driver 2017-02-19 20:35 ` [PATCH 2/2] hwrng: meson: add clock handling to driver Heiner Kallweit @ 2017-02-20 11:37 ` PrasannaKumar Muralidharan 0 siblings, 0 replies; 6+ messages in thread From: PrasannaKumar Muralidharan @ 2017-02-20 11:37 UTC (permalink / raw) To: linus-amlogic On 20 February 2017 at 02:05, Heiner Kallweit <hkallweit1@gmail.com> wrote: > Add handling of RNG0 clock to the driver. > > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> > --- > drivers/char/hw_random/meson-rng.c | 27 ++++++++++++++++++++++++++- > 1 file changed, 26 insertions(+), 1 deletion(-) > > diff --git a/drivers/char/hw_random/meson-rng.c b/drivers/char/hw_random/meson-rng.c > index 119d6984..1f586e48 100644 > --- a/drivers/char/hw_random/meson-rng.c > +++ b/drivers/char/hw_random/meson-rng.c > @@ -62,6 +62,7 @@ > #include <linux/slab.h> > #include <linux/types.h> > #include <linux/of.h> > +#include <linux/clk.h> > > #define RNG_DATA 0x00 > > @@ -69,6 +70,7 @@ struct meson_rng_data { > void __iomem *base; > struct platform_device *pdev; > struct hwrng rng; > + struct clk *core_clk; > }; > > static int meson_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait) > @@ -86,6 +88,7 @@ static int meson_rng_probe(struct platform_device *pdev) > struct device *dev = &pdev->dev; > struct meson_rng_data *data; > struct resource *res; > + int ret; Variable ret is not used. It can be removed. > data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); > if (!data) > @@ -98,12 +101,33 @@ static int meson_rng_probe(struct platform_device *pdev) > if (IS_ERR(data->base)) > return PTR_ERR(data->base); > > + data->core_clk = devm_clk_get(dev, "core"); > + if (IS_ERR(data->core_clk)) > + return PTR_ERR(data->core_clk); > + > + ret = clk_prepare_enable(data->core_clk); > + if (ret) > + return ret; > + > data->rng.name = pdev->name; > data->rng.read = meson_rng_read; > > platform_set_drvdata(pdev, data); > > - return devm_hwrng_register(dev, &data->rng); > + ret = devm_hwrng_register(dev, &data->rng); > + if (ret) > + clk_disable_unprepare(data->core_clk); > + > + return ret; > +} > + > +static int meson_rng_remove(struct platform_device *pdev) > +{ > + struct meson_rng_data *data = platform_get_drvdata(pdev); > + > + clk_disable_unprepare(data->core_clk); > + > + return 0; > } In .remove clock gets disabled before the hwrng_unregister is called. The device node '/dev/hwrng' could be accessed while meson_rng_remove is called which could lead to problems. Instead of devm_hwrng_register use hwrng_register in .probe and call hwrng_unregister in .remove. > static const struct of_device_id meson_rng_of_match[] = { > @@ -114,6 +138,7 @@ MODULE_DEVICE_TABLE(of, meson_rng_of_match); > > static struct platform_driver meson_rng_driver = { > .probe = meson_rng_probe, > + .remove = meson_rng_remove, > .driver = { > .name = "meson-rng", > .of_match_table = meson_rng_of_match, > -- > 2.11.1 > > ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 0/2] hwrng: meson: add clock handling 2017-02-19 20:30 [PATCH 0/2] hwrng: meson: add clock handling Heiner Kallweit 2017-02-19 20:33 ` [PATCH 1/2] hwrng: meson: expose RNG0 clock via DT Heiner Kallweit 2017-02-19 20:35 ` [PATCH 2/2] hwrng: meson: add clock handling to driver Heiner Kallweit @ 2017-02-21 1:58 ` Neil Armstrong 2 siblings, 0 replies; 6+ messages in thread From: Neil Armstrong @ 2017-02-21 1:58 UTC (permalink / raw) To: linus-amlogic On 02/19/2017 09:30 PM, Heiner Kallweit wrote: > The HW randon number generator requires a clock and we shouldn't rely > on the boot loader to enable it. > > Heiner Kallweit (2): > hwrng: meson: expose RNG0 clock via DT > hwrng: meson: add clock handling to driver > > arch/arm64/boot/dts/amlogic/meson-gx.dtsi | 2 +- > arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi | 5 +++++ > drivers/char/hw_random/meson-rng.c | 27 ++++++++++++++++++++++++++- > include/dt-bindings/clock/gxbb-clkc.h | 1 + > 4 files changed, 33 insertions(+), 2 deletions(-) > Hi Heiner, Thanks for the fix, but can you also update the dt-bindings document ? Documentation/devicetree/bindings/rng/amlogic,meson-rng.txt I also think this clock should be optional, to keep driver working using old bindings, set the core_clk to NULL if not available, clock_prepare_enable and clock_disable_unprepare won't fail with a NULL clock Neil ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2017-02-21 1:58 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2017-02-19 20:30 [PATCH 0/2] hwrng: meson: add clock handling Heiner Kallweit 2017-02-19 20:33 ` [PATCH 1/2] hwrng: meson: expose RNG0 clock via DT Heiner Kallweit 2017-02-20 10:07 ` Jerome Brunet 2017-02-19 20:35 ` [PATCH 2/2] hwrng: meson: add clock handling to driver Heiner Kallweit 2017-02-20 11:37 ` PrasannaKumar Muralidharan 2017-02-21 1:58 ` [PATCH 0/2] hwrng: meson: add clock handling Neil Armstrong
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