| Message ID | 1565164139-21886-5-git-send-email-t-kristo@ti.com |
|---|---|
| State | New |
| Headers | show |
| Series | soc: ti: Add OMAP PRM driver | expand |
On 20.8.2019 2.16, Suman Anna wrote: > Hi Tero, > > On 8/7/19 2:48 AM, Tero Kristo wrote: >> TI SoCs hardware reset signals require the parent clockdomain to be >> in force wakeup mode while de-asserting the reset, otherwise it may >> never complete. To support this, add pdata hooks to control the >> clockdomain directly. >> >> Signed-off-by: Tero Kristo <t-kristo@ti.com> >> --- >> drivers/soc/ti/omap_prm.c | 32 ++++++++++++++++++++++++++++---- >> include/linux/platform_data/ti-prm.h | 21 +++++++++++++++++++++ >> 2 files changed, 49 insertions(+), 4 deletions(-) >> create mode 100644 include/linux/platform_data/ti-prm.h >> >> diff --git a/drivers/soc/ti/omap_prm.c b/drivers/soc/ti/omap_prm.c >> index d412af3..870515e3 100644 >> --- a/drivers/soc/ti/omap_prm.c >> +++ b/drivers/soc/ti/omap_prm.c >> @@ -16,6 +16,8 @@ >> #include <linux/reset-controller.h> >> #include <linux/delay.h> >> >> +#include <linux/platform_data/ti-prm.h> >> + >> struct omap_rst_map { >> s8 rst; >> s8 st; >> @@ -24,6 +26,7 @@ struct omap_rst_map { >> struct omap_prm_data { >> u32 base; >> const char *name; >> + const char *clkdm_name; >> u16 pwstctrl; >> u16 pwstst; >> u16 rstctl; >> @@ -40,6 +43,8 @@ struct omap_prm { >> struct omap_reset_data { >> struct reset_controller_dev rcdev; >> struct omap_prm *prm; >> + struct clockdomain *clkdm; >> + struct device *dev; >> }; >> >> #define to_omap_reset_data(p) container_of((p), struct omap_reset_data, rcdev) >> @@ -108,6 +113,8 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev, >> int st_bit = id; >> bool has_rstst; >> int timeout = 0; >> + struct ti_prm_platform_data *pdata = dev_get_platdata(reset->dev); >> + int ret = 0; >> >> /* check the current status to avoid de-asserting the line twice */ >> v = readl_relaxed(reset->prm->base + reset->prm->data->rstctl); >> @@ -125,13 +132,16 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev, >> writel_relaxed(v, reset->prm->base + reset->prm->data->rstst); >> } >> >> + if (pdata->clkdm_deny_idle && reset->clkdm) >> + pdata->clkdm_deny_idle(reset->clkdm); >> + >> /* de-assert the reset control line */ >> v = readl_relaxed(reset->prm->base + reset->prm->data->rstctl); >> v &= ~(1 << id); >> writel_relaxed(v, reset->prm->base + reset->prm->data->rstctl); >> >> if (!has_rstst) >> - return 0; >> + goto exit; >> >> /* wait for the status to be set */ >> while (1) { >> @@ -140,13 +150,19 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev, >> if (v) >> break; >> timeout++; >> - if (timeout > OMAP_RESET_MAX_WAIT) >> - return -EBUSY; >> + if (timeout > OMAP_RESET_MAX_WAIT) { >> + ret = -EBUSY; >> + goto exit; >> + } >> >> udelay(1); >> } >> >> - return 0; >> +exit: >> + if (pdata->clkdm_allow_idle && reset->clkdm) >> + pdata->clkdm_allow_idle(reset->clkdm); >> + >> + return ret; >> } >> >> static const struct reset_control_ops omap_reset_ops = { >> @@ -159,6 +175,8 @@ static int omap_prm_reset_probe(struct platform_device *pdev, >> struct omap_prm *prm) >> { >> struct omap_reset_data *reset; >> + struct ti_prm_platform_data *pdata = dev_get_platdata(&pdev->dev); > > Please add checks for NULL callbacks. I don't think these are optional > right, so better to check in init rather than during runtime. Granted > you will probably not run into this after patch 8, but would be good to > check and print an error in case pdata quirks is missed out. Hmm ok, this would get rid of the runtime checks which would be slightly cleaner. > >> + char buf[32]; >> >> /* >> * Check if we have resets. If either rstctl or rstst is >> @@ -177,9 +195,15 @@ static int omap_prm_reset_probe(struct platform_device *pdev, >> reset->rcdev.ops = &omap_reset_ops; >> reset->rcdev.of_node = pdev->dev.of_node; >> reset->rcdev.nr_resets = OMAP_MAX_RESETS; >> + reset->dev = &pdev->dev; >> >> reset->prm = prm; >> >> + sprintf(buf, "%s_clkdm", prm->data->clkdm_name ? prm->data->clkdm_name : >> + prm->data->name); >> + >> + reset->clkdm = pdata->clkdm_lookup(buf); > > Not checking return status? clkdm will just end up being NULL in failure, which is fine for rest of the code. I don't think it can be ever NULL though, so I can add a check here for sanity. -Tero > > regards > Suman > >> + >> return devm_reset_controller_register(&pdev->dev, &reset->rcdev); >> } >> >> diff --git a/include/linux/platform_data/ti-prm.h b/include/linux/platform_data/ti-prm.h >> new file mode 100644 >> index 0000000..28154c3 >> --- /dev/null >> +++ b/include/linux/platform_data/ti-prm.h >> @@ -0,0 +1,21 @@ >> +/* SPDX-License-Identifier: GPL-2.0-only */ >> +/* >> + * TI PRM (Power & Reset Manager) platform data >> + * >> + * Copyright (C) 2019 Texas Instruments, Inc. >> + * >> + * Tero Kristo <t-kristo@ti.com> >> + */ >> + >> +#ifndef _LINUX_PLATFORM_DATA_TI_PRM_H >> +#define _LINUX_PLATFORM_DATA_TI_PRM_H >> + >> +struct clockdomain; >> + >> +struct ti_prm_platform_data { >> + void (*clkdm_deny_idle)(struct clockdomain *clkdm); >> + void (*clkdm_allow_idle)(struct clockdomain *clkdm); >> + struct clockdomain * (*clkdm_lookup)(const char *name); >> +}; >> + >> +#endif /* _LINUX_PLATFORM_DATA_TI_PRM_H */ >> > -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
diff --git a/drivers/soc/ti/omap_prm.c b/drivers/soc/ti/omap_prm.c index d412af3..870515e3 100644 --- a/drivers/soc/ti/omap_prm.c +++ b/drivers/soc/ti/omap_prm.c @@ -16,6 +16,8 @@ #include <linux/reset-controller.h> #include <linux/delay.h> +#include <linux/platform_data/ti-prm.h> + struct omap_rst_map { s8 rst; s8 st; @@ -24,6 +26,7 @@ struct omap_rst_map { struct omap_prm_data { u32 base; const char *name; + const char *clkdm_name; u16 pwstctrl; u16 pwstst; u16 rstctl; @@ -40,6 +43,8 @@ struct omap_prm { struct omap_reset_data { struct reset_controller_dev rcdev; struct omap_prm *prm; + struct clockdomain *clkdm; + struct device *dev; }; #define to_omap_reset_data(p) container_of((p), struct omap_reset_data, rcdev) @@ -108,6 +113,8 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev, int st_bit = id; bool has_rstst; int timeout = 0; + struct ti_prm_platform_data *pdata = dev_get_platdata(reset->dev); + int ret = 0; /* check the current status to avoid de-asserting the line twice */ v = readl_relaxed(reset->prm->base + reset->prm->data->rstctl); @@ -125,13 +132,16 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev, writel_relaxed(v, reset->prm->base + reset->prm->data->rstst); } + if (pdata->clkdm_deny_idle && reset->clkdm) + pdata->clkdm_deny_idle(reset->clkdm); + /* de-assert the reset control line */ v = readl_relaxed(reset->prm->base + reset->prm->data->rstctl); v &= ~(1 << id); writel_relaxed(v, reset->prm->base + reset->prm->data->rstctl); if (!has_rstst) - return 0; + goto exit; /* wait for the status to be set */ while (1) { @@ -140,13 +150,19 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev, if (v) break; timeout++; - if (timeout > OMAP_RESET_MAX_WAIT) - return -EBUSY; + if (timeout > OMAP_RESET_MAX_WAIT) { + ret = -EBUSY; + goto exit; + } udelay(1); } - return 0; +exit: + if (pdata->clkdm_allow_idle && reset->clkdm) + pdata->clkdm_allow_idle(reset->clkdm); + + return ret; } static const struct reset_control_ops omap_reset_ops = { @@ -159,6 +175,8 @@ static int omap_prm_reset_probe(struct platform_device *pdev, struct omap_prm *prm) { struct omap_reset_data *reset; + struct ti_prm_platform_data *pdata = dev_get_platdata(&pdev->dev); + char buf[32]; /* * Check if we have resets. If either rstctl or rstst is @@ -177,9 +195,15 @@ static int omap_prm_reset_probe(struct platform_device *pdev, reset->rcdev.ops = &omap_reset_ops; reset->rcdev.of_node = pdev->dev.of_node; reset->rcdev.nr_resets = OMAP_MAX_RESETS; + reset->dev = &pdev->dev; reset->prm = prm; + sprintf(buf, "%s_clkdm", prm->data->clkdm_name ? prm->data->clkdm_name : + prm->data->name); + + reset->clkdm = pdata->clkdm_lookup(buf); + return devm_reset_controller_register(&pdev->dev, &reset->rcdev); } diff --git a/include/linux/platform_data/ti-prm.h b/include/linux/platform_data/ti-prm.h new file mode 100644 index 0000000..28154c3 --- /dev/null +++ b/include/linux/platform_data/ti-prm.h @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * TI PRM (Power & Reset Manager) platform data + * + * Copyright (C) 2019 Texas Instruments, Inc. + * + * Tero Kristo <t-kristo@ti.com> + */ + +#ifndef _LINUX_PLATFORM_DATA_TI_PRM_H +#define _LINUX_PLATFORM_DATA_TI_PRM_H + +struct clockdomain; + +struct ti_prm_platform_data { + void (*clkdm_deny_idle)(struct clockdomain *clkdm); + void (*clkdm_allow_idle)(struct clockdomain *clkdm); + struct clockdomain * (*clkdm_lookup)(const char *name); +}; + +#endif /* _LINUX_PLATFORM_DATA_TI_PRM_H */
TI SoCs hardware reset signals require the parent clockdomain to be in force wakeup mode while de-asserting the reset, otherwise it may never complete. To support this, add pdata hooks to control the clockdomain directly. Signed-off-by: Tero Kristo <t-kristo@ti.com> --- drivers/soc/ti/omap_prm.c | 32 ++++++++++++++++++++++++++++---- include/linux/platform_data/ti-prm.h | 21 +++++++++++++++++++++ 2 files changed, 49 insertions(+), 4 deletions(-) create mode 100644 include/linux/platform_data/ti-prm.h -- 1.9.1 -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki