From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tero Kristo Subject: [PATCH 4/8] soc: ti: omap-prm: add support for denying idle for reset clockdomain Date: Wed, 7 Aug 2019 10:48:55 +0300 Message-ID: <1565164139-21886-5-git-send-email-t-kristo@ti.com> References: <1565164139-21886-1-git-send-email-t-kristo@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1565164139-21886-1-git-send-email-t-kristo@ti.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: ssantosh@kernel.org, linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, robh+dt@kernel.org Cc: tony@atomide.com, devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org 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 --- 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 #include +#include + 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 + */ + +#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 */ -- 1.9.1 -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki