Re: [PATCH v4 5/5] clk: aspeed: Add reset controller

From: Andrew Jeffery
Date: Thu Oct 05 2017 - 03:47:22 EST


On Tue, 2017-10-03 at 17:25 +1030, Joel Stanley wrote:
> There are some resets that are not associated with gates. These are
> represented by a reset controller.
>Â
> Signed-off-by: Joel Stanley <joel@xxxxxxxxx>

With respect to the Aspeed hardware reset bits:

Reviewed-by: Andrew Jeffery <andrew@xxxxxxxx>

>Â
> ---
> v3:
> Â - Add named initalisers for the reset defines
> Â - Add define for ADC
> ---
> Âdrivers/clk/clk-aspeed.cÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ| 82 +++++++++++++++++++++++++++++++-
> Âinclude/dt-bindings/clock/aspeed-clock.h | 10 ++++
> Â2 files changed, 91 insertions(+), 1 deletion(-)
>Â
> diff --git a/drivers/clk/clk-aspeed.c b/drivers/clk/clk-aspeed.c
> index a424b056e767..de491dc7f955 100644
> --- a/drivers/clk/clk-aspeed.c
> +++ b/drivers/clk/clk-aspeed.c
> @@ -17,6 +17,7 @@
> Â#include <linux/of_device.h>
> Â#include <linux/platform_device.h>
> Â#include <linux/regmap.h>
> +#include <linux/reset-controller.h>
> Â#include <linux/slab.h>
> Â#include <linux/spinlock.h>
> Â
> @@ -292,6 +293,68 @@ static const struct clk_ops aspeed_clk_gate_ops = {
> Â .is_enabled = aspeed_clk_is_enabled,
> Â};
> Â
> +/**
> + * struct aspeed_reset - Aspeed reset controller
> + * @map: regmap to access the containing system controller
> + * @rcdev: reset controller device
> + */
> +struct aspeed_reset {
> + struct regmap *map;
> + struct reset_controller_dev rcdev;
> +};
> +
> +#define to_aspeed_reset(p) container_of((p), struct aspeed_reset, rcdev)
> +
> +static const u8 aspeed_resets[] = {
> + [ASPEED_RESET_XDMA] = 25,
> + [ASPEED_RESET_MCTP] = 24,
> + [ASPEED_RESET_ADC] = 23,
> + [ASPEED_RESET_JTAG_MASTER] = 22,
> + [ASPEED_RESET_MIC] = 18,
> + [ASPEED_RESET_PWM] =ÂÂ9,
> + [ASPEED_RESET_PCIVGA] =ÂÂ8,
> + [ASPEED_RESET_I2C] =ÂÂ2,
> + [ASPEED_RESET_AHB] =ÂÂ1,
> +};
> +
> +static int aspeed_reset_deassert(struct reset_controller_dev *rcdev,
> + Âunsigned long id)
> +{
> + struct aspeed_reset *ar = to_aspeed_reset(rcdev);
> + u32 rst = BIT(aspeed_resets[id]);
> +
> + return regmap_update_bits(ar->map, ASPEED_RESET_CTRL, rst, 0);
> +}
> +
> +static int aspeed_reset_assert(struct reset_controller_dev *rcdev,
> + ÂÂÂÂÂÂÂunsigned long id)
> +{
> + struct aspeed_reset *ar = to_aspeed_reset(rcdev);
> + u32 rst = BIT(aspeed_resets[id]);
> +
> + return regmap_update_bits(ar->map, ASPEED_RESET_CTRL, rst, rst);
> +}
> +
> +static int aspeed_reset_status(struct reset_controller_dev *rcdev,
> + ÂÂÂÂÂÂÂunsigned long id)
> +{
> + struct aspeed_reset *ar = to_aspeed_reset(rcdev);
> + u32 val, rst = BIT(aspeed_resets[id]);
> + int ret;
> +
> + ret = regmap_read(ar->map, ASPEED_RESET_CTRL, &val);
> + if (ret)
> + return ret;
> +
> + return !!(val & rst);
> +}
> +
> +static const struct reset_control_ops aspeed_reset_ops = {
> + .assert = aspeed_reset_assert,
> + .deassert = aspeed_reset_deassert,
> + .status = aspeed_reset_status,
> +};
> +
> Âstatic struct clk_hw *aspeed_clk_hw_register_gate(struct device *dev,
> Â const char *name, const char *parent_name, unsigned long flags,
> Â struct regmap *map, u8 clock_idx, u8 reset_idx,
> @@ -333,10 +396,11 @@ static int aspeed_clk_probe(struct platform_device *pdev)
> Â{
> Â const struct aspeed_clk_soc_data *soc_data;
> Â struct device *dev = &pdev->dev;
> + struct aspeed_reset *ar;
> Â struct regmap *map;
> Â struct clk_hw *hw;
> Â u32 val, rate;
> - int i;
> + int i, ret;
> Â
> Â map = syscon_node_to_regmap(dev->of_node);
> Â if (IS_ERR(map)) {
> @@ -344,6 +408,22 @@ static int aspeed_clk_probe(struct platform_device *pdev)
> Â return PTR_ERR(map);
> Â }
> Â
> + ar = devm_kzalloc(dev, sizeof(*ar), GFP_KERNEL);
> + if (!ar)
> + return -ENOMEM;
> +
> + ar->map = map;
> + ar->rcdev.owner = THIS_MODULE;
> + ar->rcdev.nr_resets = ARRAY_SIZE(aspeed_resets);
> + ar->rcdev.ops = &aspeed_reset_ops;
> + ar->rcdev.of_node = dev->of_node;
> +
> + ret = devm_reset_controller_register(dev, &ar->rcdev);
> + if (ret) {
> + dev_err(dev, "could not register reset controller\n");
> + return ret;
> + }
> +
> Â /* SoC generations share common layouts but have different divisors */
> Â soc_data = of_device_get_match_data(dev);
> Â if (!soc_data) {
> diff --git a/include/dt-bindings/clock/aspeed-clock.h b/include/dt-bindings/clock/aspeed-clock.h
> index 4a99421d77c8..8e19646d8025 100644
> --- a/include/dt-bindings/clock/aspeed-clock.h
> +++ b/include/dt-bindings/clock/aspeed-clock.h
> @@ -39,4 +39,14 @@
> Â
> Â#define ASPEED_NUM_CLKS 35
> Â
> +#define ASPEED_RESET_XDMA 0
> +#define ASPEED_RESET_MCTP 1
> +#define ASPEED_RESET_ADC 2
> +#define ASPEED_RESET_JTAG_MASTER 3
> +#define ASPEED_RESET_MIC 4
> +#define ASPEED_RESET_PWM 5
> +#define ASPEED_RESET_PCIVGA 6
> +#define ASPEED_RESET_I2C 7
> +#define ASPEED_RESET_AHB 8
> +
> Â#endif

Attachment: signature.asc
Description: This is a digitally signed message part