| Message ID | 20220608083942.1584087-1-claudiu.beznea@microchip.com |
|---|---|
| Headers | show |
| Series | power: reset: at91-reset: add support for sama7g5 | expand |
On 08/06/2022 10:39, Claudiu Beznea wrote: > Use generic name for reset controller of AT91 devices to comply with > DT specifications. > > Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> > Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Best regards, Krzysztof
Hi, On Wed, Jun 08, 2022 at 11:39:40AM +0300, Claudiu Beznea wrote: > SAMA7G5 reset controller has 5 extra lines that goes to different devices > (3 lines to USB PHYs, 1 line to DDR controller, 1 line to DDR PHY > controller). These reset lines could be requested by different controller > drivers (e.g. USB PHY driver) and these controllers' drivers could > assert/deassert these lines when necessary. Thus add support for > reset_controller_dev which brings this functionality. > > Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> > Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> > --- > drivers/power/reset/at91-reset.c | 106 +++++++++++++++++++++++++++++-- > 1 file changed, 102 insertions(+), 4 deletions(-) > > diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c > index 1b2aca3f490d..e25d8d38a2f8 100644 > --- a/drivers/power/reset/at91-reset.c > +++ b/drivers/power/reset/at91-reset.c > @@ -17,10 +17,13 @@ > #include <linux/of_address.h> > #include <linux/platform_device.h> > #include <linux/reboot.h> > +#include <linux/reset-controller.h> > > #include <soc/at91/at91sam9_ddrsdr.h> > #include <soc/at91/at91sam9_sdramc.h> > > +#include <dt-bindings/reset/sama7g5-reset.h> > + > #define AT91_RSTC_CR 0x00 /* Reset Controller Control Register */ > #define AT91_RSTC_PROCRST BIT(0) /* Processor Reset */ > #define AT91_RSTC_PERRST BIT(2) /* Peripheral Reset */ > @@ -65,7 +68,10 @@ enum reset_type { > * struct at91_reset - AT91 reset specific data structure > * @rstc_base: base address for system reset > * @ramc_base: array with base addresses of RAM controllers > + * @dev_base: base address for devices reset > * @sclk: slow clock > + * @rcdev: reset controller device > + * @lock: lock for devices reset register access > * @nb: reset notifier block > * @args: SoC specific system reset arguments > * @ramc_lpr: SDRAM Controller Low Power Register > @@ -73,12 +79,17 @@ enum reset_type { > struct at91_reset { > void __iomem *rstc_base; > void __iomem *ramc_base[2]; > + void __iomem *dev_base; > struct clk *sclk; > + struct reset_controller_dev rcdev; > + spinlock_t lock; > struct notifier_block nb; > u32 args; > u32 ramc_lpr; > }; > > +#define to_at91_reset(r) container_of(r, struct at91_reset, rcdev) > + > /** > * struct at91_reset_data - AT91 reset data > * @reset_args: SoC specific system reset arguments > @@ -216,6 +227,87 @@ static const struct of_device_id at91_reset_of_match[] = { > }; > MODULE_DEVICE_TABLE(of, at91_reset_of_match); > > +static int at91_reset_update(struct reset_controller_dev *rcdev, > + unsigned long id, bool assert) > +{ > + struct at91_reset *reset = to_at91_reset(rcdev); > + unsigned long flags; > + u32 val; > + > + spin_lock_irqsave(&reset->lock, flags); > + val = readl_relaxed(reset->dev_base); > + if (assert) > + val |= BIT(id); > + else > + val &= ~BIT(id); > + writel_relaxed(val, reset->dev_base); > + spin_unlock_irqrestore(&reset->lock, flags); > + > + return 0; > +} > + > +static int at91_reset_assert(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + return at91_reset_update(rcdev, id, true); > +} > + > +static int at91_reset_deassert(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + return at91_reset_update(rcdev, id, false); > +} > + > +static int at91_reset_dev_status(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + struct at91_reset *reset = to_at91_reset(rcdev); > + u32 val; > + > + val = readl_relaxed(reset->dev_base); > + > + return !!(val & BIT(id)); > +} > + > +static const struct reset_control_ops at91_reset_ops = { > + .assert = at91_reset_assert, > + .deassert = at91_reset_deassert, > + .status = at91_reset_dev_status, > +}; > + > +static int at91_reset_of_xlate(struct reset_controller_dev *rcdev, > + const struct of_phandle_args *reset_spec) > +{ > + if (reset_spec->args[0] < SAMA7G5_RESET_USB_PHY1 || > + reset_spec->args[0] > SAMA7G5_RESET_USB_PHY3) > + return -EINVAL; Can you move the min/max info to the devce info struct, so that this stays as generic as the name suggests (and is prepared for future devices)? -- Sebastian > + return reset_spec->args[0]; > +} > + > +static int at91_rcdev_init(struct at91_reset *reset, > + const struct at91_reset_data *data, > + struct platform_device *pdev) > +{ > + if (!data->n_device_reset) > + return 0; > + > + reset->dev_base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 1, > + NULL); > + if (IS_ERR(reset->dev_base)) > + return -ENODEV; > + > + spin_lock_init(&reset->lock); > + reset->rcdev.ops = &at91_reset_ops; > + reset->rcdev.owner = THIS_MODULE; > + reset->rcdev.of_node = pdev->dev.of_node; > + reset->rcdev.nr_resets = data->n_device_reset; > + reset->rcdev.of_reset_n_cells = 1; > + reset->rcdev.of_xlate = at91_reset_of_xlate; > + > + return devm_reset_controller_register(&pdev->dev, &reset->rcdev); > +} > + > static int __init at91_reset_probe(struct platform_device *pdev) > { > const struct of_device_id *match; > @@ -269,6 +361,10 @@ static int __init at91_reset_probe(struct platform_device *pdev) > > platform_set_drvdata(pdev, reset); > > + ret = at91_rcdev_init(reset, data, pdev); > + if (ret) > + goto disable_clk; > + > if (of_device_is_compatible(pdev->dev.of_node, "microchip,sam9x60-rstc")) { > u32 val = readl(reset->rstc_base + AT91_RSTC_MR); > > @@ -277,14 +373,16 @@ static int __init at91_reset_probe(struct platform_device *pdev) > } > > ret = register_restart_handler(&reset->nb); > - if (ret) { > - clk_disable_unprepare(reset->sclk); > - return ret; > - } > + if (ret) > + goto disable_clk; > > at91_reset_status(pdev, reset->rstc_base); > > return 0; > + > +disable_clk: > + clk_disable_unprepare(reset->sclk); > + return ret; > } > > static int __exit at91_reset_remove(struct platform_device *pdev) > -- > 2.33.0 >