* [PATCH] reset: meson: add level reset support for GX SoC family
@ 2017-10-16 15:26 Neil Armstrong
2017-10-17 10:08 ` Philipp Zabel
0 siblings, 1 reply; 3+ messages in thread
From: Neil Armstrong @ 2017-10-16 15:26 UTC (permalink / raw)
To: linus-amlogic
The Amlogic GX SoC family embeds alternate registers to drive the reset
levels next to the pulse registers.
This patch adds support for level reset handling on the GX family only.
The Meson8 family has an alternate way to handle level reset.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
drivers/reset/reset-meson.c | 57 +++++++++++++++++++++++++++++++++++++++++----
1 file changed, 53 insertions(+), 4 deletions(-)
diff --git a/drivers/reset/reset-meson.c b/drivers/reset/reset-meson.c
index a8b915e..d55e440 100644
--- a/drivers/reset/reset-meson.c
+++ b/drivers/reset/reset-meson.c
@@ -62,9 +62,11 @@
#include <linux/reset-controller.h>
#include <linux/slab.h>
#include <linux/types.h>
+#include <linux/of_device.h>
#define REG_COUNT 8
#define BITS_PER_REG 32
+#define LEVEL_OFFSET 0x7c
struct meson_reset {
void __iomem *reg_base;
@@ -88,18 +90,61 @@ static int meson_reset_reset(struct reset_controller_dev *rcdev,
return 0;
}
-static const struct reset_control_ops meson_reset_ops = {
+static int meson_reset_level(struct reset_controller_dev *rcdev,
+ unsigned long id, bool assert)
+{
+ struct meson_reset *data =
+ container_of(rcdev, struct meson_reset, rcdev);
+ unsigned int bank = id / BITS_PER_REG;
+ unsigned int offset = id % BITS_PER_REG;
+ void __iomem *reg_addr = data->reg_base + LEVEL_OFFSET + (bank << 2);
+ u32 reg;
+
+ if (bank >= REG_COUNT)
+ return -EINVAL;
+
+ reg = readl(reg_addr);
+ if (assert)
+ writel(reg & ~BIT(offset), reg_addr);
+ else
+ writel(reg | BIT(offset), reg_addr);
+
+ return 0;
+}
+
+static int meson_reset_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return meson_reset_level(rcdev, id, true);
+}
+
+static int meson_reset_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return meson_reset_level(rcdev, id, false);
+}
+
+static const struct reset_control_ops meson_reset_meson8_ops = {
+ .reset = meson_reset_reset,
+};
+
+static const struct reset_control_ops meson_reset_gx_ops = {
.reset = meson_reset_reset,
+ .assert = meson_reset_assert,
+ .deassert = meson_reset_deassert,
};
static const struct of_device_id meson_reset_dt_ids[] = {
- { .compatible = "amlogic,meson8b-reset", },
- { .compatible = "amlogic,meson-gxbb-reset", },
+ { .compatible = "amlogic,meson8b-reset",
+ .data = (void *) &meson_reset_meson8_ops, },
+ { .compatible = "amlogic,meson-gxbb-reset",
+ .data = (void *) &meson_reset_gx_ops, },
{ /* sentinel */ },
};
static int meson_reset_probe(struct platform_device *pdev)
{
+ const struct reset_control_ops *ops;
struct meson_reset *data;
struct resource *res;
@@ -107,6 +152,10 @@ static int meson_reset_probe(struct platform_device *pdev)
if (!data)
return -ENOMEM;
+ ops = of_device_get_match_data(&pdev->dev);
+ if (!ops)
+ return -EINVAL;
+
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
data->reg_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(data->reg_base))
@@ -116,7 +165,7 @@ static int meson_reset_probe(struct platform_device *pdev)
data->rcdev.owner = THIS_MODULE;
data->rcdev.nr_resets = REG_COUNT * BITS_PER_REG;
- data->rcdev.ops = &meson_reset_ops;
+ data->rcdev.ops = ops;
data->rcdev.of_node = pdev->dev.of_node;
return devm_reset_controller_register(&pdev->dev, &data->rcdev);
--
2.7.4
^ permalink raw reply [flat|nested] 3+ messages in thread* [PATCH] reset: meson: add level reset support for GX SoC family
2017-10-16 15:26 [PATCH] reset: meson: add level reset support for GX SoC family Neil Armstrong
@ 2017-10-17 10:08 ` Philipp Zabel
2017-10-17 10:09 ` Neil Armstrong
0 siblings, 1 reply; 3+ messages in thread
From: Philipp Zabel @ 2017-10-17 10:08 UTC (permalink / raw)
To: linus-amlogic
Hi Neil,
On Mon, 2017-10-16 at 17:26 +0200, Neil Armstrong wrote:
> The Amlogic GX SoC family embeds alternate registers to drive the reset
> levels next to the pulse registers.
>
> This patch adds support for level reset handling on the GX family only.
>
> The Meson8 family has an alternate way to handle level reset.
>
> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
thank you for the patch, comments below:
> ---
> drivers/reset/reset-meson.c | 57 +++++++++++++++++++++++++++++++++++++++++----
> 1 file changed, 53 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/reset/reset-meson.c b/drivers/reset/reset-meson.c
> index a8b915e..d55e440 100644
> --- a/drivers/reset/reset-meson.c
> +++ b/drivers/reset/reset-meson.c
> @@ -62,9 +62,11 @@
> #include <linux/reset-controller.h>
> #include <linux/slab.h>
> #include <linux/types.h>
> +#include <linux/of_device.h>
>
> #define REG_COUNT 8
> #define BITS_PER_REG 32
> +#define LEVEL_OFFSET 0x7c
>
> struct meson_reset {
> void __iomem *reg_base;
> @@ -88,18 +90,61 @@ static int meson_reset_reset(struct reset_controller_dev *rcdev,
> return 0;
> }
>
> -static const struct reset_control_ops meson_reset_ops = {
> +static int meson_reset_level(struct reset_controller_dev *rcdev,
> + unsigned long id, bool assert)
> +{
> + struct meson_reset *data =
> + container_of(rcdev, struct meson_reset, rcdev);
> + unsigned int bank = id / BITS_PER_REG;
> + unsigned int offset = id % BITS_PER_REG;
> + void __iomem *reg_addr = data->reg_base + LEVEL_OFFSET + (bank << 2);
> + u32 reg;
> +
> + if (bank >= REG_COUNT)
> + return -EINVAL;
This check is not necessary. The same check is in meson_reset_reset,
which I didn't notice last time.
of_reset_simple_xlate, the default rcdev->of_xlate implementation,
already guarantees id < rcdev->nr_resets. And since nr_resets is set to
REG_COUNT * BITS_PER_REG, we know that id < REG_COUNT * BITS_PER_REG and
thus bank <= id / BITS_PER_REG < REG_COUNT.
> + reg = readl(reg_addr);
> + if (assert)
> + writel(reg & ~BIT(offset), reg_addr);
> + else
> + writel(reg | BIT(offset), reg_addr);
These read-modify-write operations must be protected by a spinlock.
> +
> + return 0;
> +}
> +
> +static int meson_reset_assert(struct reset_controller_dev *rcdev,
> + unsigned long id)
> +{
> + return meson_reset_level(rcdev, id, true);
> +}
> +
> +static int meson_reset_deassert(struct reset_controller_dev *rcdev,
> + unsigned long id)
> +{
> + return meson_reset_level(rcdev, id, false);
> +}
> +
> +static const struct reset_control_ops meson_reset_meson8_ops = {
> + .reset = meson_reset_reset,
> +};
> +
> +static const struct reset_control_ops meson_reset_gx_ops = {
> .reset = meson_reset_reset,
> + .assert = meson_reset_assert,
> + .deassert = meson_reset_deassert,
> };
>
> static const struct of_device_id meson_reset_dt_ids[] = {
> - { .compatible = "amlogic,meson8b-reset", },
> - { .compatible = "amlogic,meson-gxbb-reset", },
> + { .compatible = "amlogic,meson8b-reset",
> + .data = (void *) &meson_reset_meson8_ops, },
> + { .compatible = "amlogic,meson-gxbb-reset",
> + .data = (void *) &meson_reset_gx_ops, },
> { /* sentinel */ },
> };
of_device_id.data ist const void *, so there is no need to cast here.
> static int meson_reset_probe(struct platform_device *pdev)
> {
> + const struct reset_control_ops *ops;
> struct meson_reset *data;
> struct resource *res;
>
> @@ -107,6 +152,10 @@ static int meson_reset_probe(struct platform_device *pdev)
> if (!data)
> return -ENOMEM;
>
> + ops = of_device_get_match_data(&pdev->dev);
> + if (!ops)
> + return -EINVAL;
> +
> res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> data->reg_base = devm_ioremap_resource(&pdev->dev, res);
> if (IS_ERR(data->reg_base))
> @@ -116,7 +165,7 @@ static int meson_reset_probe(struct platform_device *pdev)
>
> data->rcdev.owner = THIS_MODULE;
> data->rcdev.nr_resets = REG_COUNT * BITS_PER_REG;
> - data->rcdev.ops = &meson_reset_ops;
> + data->rcdev.ops = ops;
> data->rcdev.of_node = pdev->dev.of_node;
>
> return devm_reset_controller_register(&pdev->dev, &data->rcdev);
regards
Philipp
^ permalink raw reply [flat|nested] 3+ messages in thread* [PATCH] reset: meson: add level reset support for GX SoC family
2017-10-17 10:08 ` Philipp Zabel
@ 2017-10-17 10:09 ` Neil Armstrong
0 siblings, 0 replies; 3+ messages in thread
From: Neil Armstrong @ 2017-10-17 10:09 UTC (permalink / raw)
To: linus-amlogic
On 17/10/2017 12:08, Philipp Zabel wrote:
> Hi Neil,
>
> On Mon, 2017-10-16 at 17:26 +0200, Neil Armstrong wrote:
>> The Amlogic GX SoC family embeds alternate registers to drive the reset
>> levels next to the pulse registers.
>>
>> This patch adds support for level reset handling on the GX family only.
>>
>> The Meson8 family has an alternate way to handle level reset.
>>
>> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
>
> thank you for the patch, comments below:
>
>> ---
>> drivers/reset/reset-meson.c | 57 +++++++++++++++++++++++++++++++++++++++++----
>> 1 file changed, 53 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/reset/reset-meson.c b/drivers/reset/reset-meson.c
>> index a8b915e..d55e440 100644
>> --- a/drivers/reset/reset-meson.c
>> +++ b/drivers/reset/reset-meson.c
>> @@ -62,9 +62,11 @@
>> #include <linux/reset-controller.h>
>> #include <linux/slab.h>
>> #include <linux/types.h>
>> +#include <linux/of_device.h>
>>
>> #define REG_COUNT 8
>> #define BITS_PER_REG 32
>> +#define LEVEL_OFFSET 0x7c
>>
>> struct meson_reset {
>> void __iomem *reg_base;
>> @@ -88,18 +90,61 @@ static int meson_reset_reset(struct reset_controller_dev *rcdev,
>> return 0;
>> }
>>
>> -static const struct reset_control_ops meson_reset_ops = {
>> +static int meson_reset_level(struct reset_controller_dev *rcdev,
>> + unsigned long id, bool assert)
>> +{
>> + struct meson_reset *data =
>> + container_of(rcdev, struct meson_reset, rcdev);
>> + unsigned int bank = id / BITS_PER_REG;
>> + unsigned int offset = id % BITS_PER_REG;
>> + void __iomem *reg_addr = data->reg_base + LEVEL_OFFSET + (bank << 2);
>> + u32 reg;
>> +
>> + if (bank >= REG_COUNT)
>> + return -EINVAL;
>
> This check is not necessary. The same check is in meson_reset_reset,
> which I didn't notice last time.
>
> of_reset_simple_xlate, the default rcdev->of_xlate implementation,
> already guarantees id < rcdev->nr_resets. And since nr_resets is set to
> REG_COUNT * BITS_PER_REG, we know that id < REG_COUNT * BITS_PER_REG and
> thus bank <= id / BITS_PER_REG < REG_COUNT.
Ok will remove.
>
>> + reg = readl(reg_addr);
>> + if (assert)
>> + writel(reg & ~BIT(offset), reg_addr);
>> + else
>> + writel(reg | BIT(offset), reg_addr);
>
> These read-modify-write operations must be protected by a spinlock.
Ok will add
>
>> +
>> + return 0;
>> +}
>> +
>> +static int meson_reset_assert(struct reset_controller_dev *rcdev,
>> + unsigned long id)
>> +{
>> + return meson_reset_level(rcdev, id, true);
>> +}
>> +
>> +static int meson_reset_deassert(struct reset_controller_dev *rcdev,
>> + unsigned long id)
>> +{
>> + return meson_reset_level(rcdev, id, false);
>> +}
>> +
>> +static const struct reset_control_ops meson_reset_meson8_ops = {
>> + .reset = meson_reset_reset,
>> +};
>> +
>> +static const struct reset_control_ops meson_reset_gx_ops = {
>> .reset = meson_reset_reset,
>> + .assert = meson_reset_assert,
>> + .deassert = meson_reset_deassert,
>> };
>>
>> static const struct of_device_id meson_reset_dt_ids[] = {
>> - { .compatible = "amlogic,meson8b-reset", },
>> - { .compatible = "amlogic,meson-gxbb-reset", },
>> + { .compatible = "amlogic,meson8b-reset",
>> + .data = (void *) &meson_reset_meson8_ops, },
>> + { .compatible = "amlogic,meson-gxbb-reset",
>> + .data = (void *) &meson_reset_gx_ops, },
>> { /* sentinel */ },
>> };
>
> of_device_id.data ist const void *, so there is no need to cast here.
Ok will remove then
>
>> static int meson_reset_probe(struct platform_device *pdev)
>> {
>> + const struct reset_control_ops *ops;
>> struct meson_reset *data;
>> struct resource *res;
>>
>> @@ -107,6 +152,10 @@ static int meson_reset_probe(struct platform_device *pdev)
>> if (!data)
>> return -ENOMEM;
>>
>> + ops = of_device_get_match_data(&pdev->dev);
>> + if (!ops)
>> + return -EINVAL;
>> +
>> res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> data->reg_base = devm_ioremap_resource(&pdev->dev, res);
>> if (IS_ERR(data->reg_base))
>> @@ -116,7 +165,7 @@ static int meson_reset_probe(struct platform_device *pdev)
>>
>> data->rcdev.owner = THIS_MODULE;
>> data->rcdev.nr_resets = REG_COUNT * BITS_PER_REG;
>> - data->rcdev.ops = &meson_reset_ops;
>> + data->rcdev.ops = ops;
>> data->rcdev.of_node = pdev->dev.of_node;
>>
>> return devm_reset_controller_register(&pdev->dev, &data->rcdev);
>
> regards
> Philipp
>
Thanks,
Neil
^ permalink raw reply [flat|nested] 3+ messages in thread
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2017-10-16 15:26 [PATCH] reset: meson: add level reset support for GX SoC family Neil Armstrong
2017-10-17 10:08 ` Philipp Zabel
2017-10-17 10:09 ` Neil Armstrong
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