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@xxxxxx>
---
drivers/soc/ti/omap_prm.c | 36 ++++++++++++++++++++++++++--
include/linux/platform_data/ti-prm.h | 21 ++++++++++++++++
2 files changed, 55 insertions(+), 2 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 d70f64e7a5c8..0b6a300f935b 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 rstctrl;
u16 rstst;
const struct omap_rst_map *rstmap;
@@ -40,6 +43,8 @@ struct omap_reset_data {
struct omap_prm *prm;
u32 mask;
spinlock_t lock;
+ struct clockdomain *clkdm;
+ struct device *dev;
};
#define to_omap_reset_data(p) container_of((p), struct omap_reset_data, rcdev)
@@ -49,6 +54,7 @@ struct omap_reset_data {
#define OMAP_PRM_HAS_RSTCTRL BIT(0)
#define OMAP_PRM_HAS_RSTST BIT(1)
+#define OMAP_PRM_HAS_NO_CLKDM BIT(2)
#define OMAP_PRM_HAS_RESETS (OMAP_PRM_HAS_RSTCTRL | OMAP_PRM_HAS_RSTST)
@@ -133,6 +139,8 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
int st_bit;
bool has_rstst;
unsigned long flags;
+ struct ti_prm_platform_data *pdata = dev_get_platdata(reset->dev);
+ int ret = 0;
has_rstst = reset->prm->data->rstst ||
(reset->prm->data->flags & OMAP_PRM_HAS_RSTST);
@@ -146,6 +154,9 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
writel_relaxed(v, reset->prm->base + reset->prm->data->rstst);
}
+ if (reset->clkdm)
+ pdata->clkdm_deny_idle(reset->clkdm);
+
/* de-assert the reset control line */
spin_lock_irqsave(&reset->lock, flags);
v = readl_relaxed(reset->prm->base + reset->prm->data->rstctrl);
@@ -154,7 +165,7 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
spin_unlock_irqrestore(&reset->lock, flags);
if (!has_rstst)
- return 0;
+ goto exit;
/* wait for the status to be set */
ret = readl_relaxed_poll_timeout(reset->prm->base +
@@ -165,7 +176,11 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
pr_err("%s: timedout waiting for %s:%lu\n", __func__,
dev_name(rcdev->dev), id);
- return 0;
+exit:
+ if (reset->clkdm)
+ pdata->clkdm_allow_idle(reset->clkdm);
+
+ return ret;
}
static const struct reset_control_ops omap_reset_ops = {
@@ -190,6 +205,8 @@ static int omap_prm_reset_init(struct platform_device *pdev,
{
struct omap_reset_data *reset;
const struct omap_rst_map *map;
+ struct ti_prm_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ char buf[32];
/*
* Check if we have controllable resets. If either rstctrl is non-zero
@@ -199,6 +216,11 @@ static int omap_prm_reset_init(struct platform_device *pdev,
if (!prm->data->rstctrl && !(prm->data->flags & OMAP_PRM_HAS_RSTCTRL))
return 0;
+ /* Check if we have the pdata callbacks in place */
+ if (!pdata || !pdata->clkdm_lookup || !pdata->clkdm_deny_idle ||
+ !pdata->clkdm_allow_idle)
+ return -EINVAL;
+
map = prm->data->rstmap;
if (!map)
return -EINVAL;
@@ -213,10 +235,20 @@ static int omap_prm_reset_init(struct platform_device *pdev,
reset->rcdev.nr_resets = OMAP_MAX_RESETS;
reset->rcdev.of_xlate = omap_prm_reset_xlate;
reset->rcdev.of_reset_n_cells = 1;
+ reset->dev = &pdev->dev;
spin_lock_init(&reset->lock);
reset->prm = prm;
+ sprintf(buf, "%s_clkdm", prm->data->clkdm_name ? prm->data->clkdm_name :
+ prm->data->name);
+
+ if (!(prm->data->flags & OMAP_PRM_HAS_NO_CLKDM)) {
+ reset->clkdm = pdata->clkdm_lookup(buf);
+ if (!reset->clkdm)
+ return -EINVAL;
+ }
+
while (map->rst >= 0) {
reset->mask |= BIT(map->rst);
map++;
diff --git a/include/linux/platform_data/ti-prm.h b/include/linux/platform_data/ti-prm.h
new file mode 100644
index 000000000000..28154c3226c2
--- /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@xxxxxx>
+ */
+
+#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 */
--
2.17.1
--
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