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path: root/drivers/clk/qcom/gdsc.c
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Diffstat (limited to 'drivers/clk/qcom/gdsc.c')
-rw-r--r--drivers/clk/qcom/gdsc.c89
1 files changed, 70 insertions, 19 deletions
diff --git a/drivers/clk/qcom/gdsc.c b/drivers/clk/qcom/gdsc.c
index da9fad8b642b..f12d7b2bddd7 100644
--- a/drivers/clk/qcom/gdsc.c
+++ b/drivers/clk/qcom/gdsc.c
@@ -16,6 +16,7 @@
#include <linux/err.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
+#include <linux/ktime.h>
#include <linux/pm_domain.h>
#include <linux/regmap.h>
#include <linux/reset-controller.h>
@@ -42,12 +43,12 @@
#define domain_to_gdsc(domain) container_of(domain, struct gdsc, pd)
-static int gdsc_is_enabled(struct gdsc *sc)
+static int gdsc_is_enabled(struct gdsc *sc, unsigned int reg)
{
u32 val;
int ret;
- ret = regmap_read(sc->regmap, sc->gdscr, &val);
+ ret = regmap_read(sc->regmap, reg, &val);
if (ret)
return ret;
@@ -58,28 +59,46 @@ static int gdsc_toggle_logic(struct gdsc *sc, bool en)
{
int ret;
u32 val = en ? 0 : SW_COLLAPSE_MASK;
- u32 check = en ? PWR_ON_MASK : 0;
- unsigned long timeout;
+ ktime_t start;
+ unsigned int status_reg = sc->gdscr;
ret = regmap_update_bits(sc->regmap, sc->gdscr, SW_COLLAPSE_MASK, val);
if (ret)
return ret;
- timeout = jiffies + usecs_to_jiffies(TIMEOUT_US);
- do {
- ret = regmap_read(sc->regmap, sc->gdscr, &val);
- if (ret)
- return ret;
+ /* If disabling votable gdscs, don't poll on status */
+ if ((sc->flags & VOTABLE) && !en) {
+ /*
+ * Add a short delay here to ensure that an enable
+ * right after it was disabled does not put it in an
+ * unknown state
+ */
+ udelay(TIMEOUT_US);
+ return 0;
+ }
- if ((val & PWR_ON_MASK) == check)
- return 0;
- } while (time_before(jiffies, timeout));
+ if (sc->gds_hw_ctrl) {
+ status_reg = sc->gds_hw_ctrl;
+ /*
+ * The gds hw controller asserts/de-asserts the status bit soon
+ * after it receives a power on/off request from a master.
+ * The controller then takes around 8 xo cycles to start its
+ * internal state machine and update the status bit. During
+ * this time, the status bit does not reflect the true status
+ * of the core.
+ * Add a delay of 1 us between writing to the SW_COLLAPSE bit
+ * and polling the status bit.
+ */
+ udelay(1);
+ }
- ret = regmap_read(sc->regmap, sc->gdscr, &val);
- if (ret)
- return ret;
+ start = ktime_get();
+ do {
+ if (gdsc_is_enabled(sc, status_reg) == en)
+ return 0;
+ } while (ktime_us_delta(ktime_get(), start) < TIMEOUT_US);
- if ((val & PWR_ON_MASK) == check)
+ if (gdsc_is_enabled(sc, status_reg) == en)
return 0;
return -ETIMEDOUT;
@@ -165,6 +184,7 @@ static int gdsc_init(struct gdsc *sc)
{
u32 mask, val;
int on, ret;
+ unsigned int reg;
/*
* Disable HW trigger: collapse/restore occur based on registers writes.
@@ -185,10 +205,18 @@ static int gdsc_init(struct gdsc *sc)
return ret;
}
- on = gdsc_is_enabled(sc);
+ reg = sc->gds_hw_ctrl ? sc->gds_hw_ctrl : sc->gdscr;
+ on = gdsc_is_enabled(sc, reg);
if (on < 0)
return on;
+ /*
+ * Votable GDSCs can be ON due to Vote from other masters.
+ * If a Votable GDSC is ON, make sure we have a Vote.
+ */
+ if ((sc->flags & VOTABLE) && on)
+ gdsc_enable(&sc->pd);
+
if (on || (sc->pwrsts & PWRSTS_RET))
gdsc_force_mem_on(sc);
else
@@ -201,11 +229,14 @@ static int gdsc_init(struct gdsc *sc)
return 0;
}
-int gdsc_register(struct device *dev, struct gdsc **scs, size_t num,
+int gdsc_register(struct gdsc_desc *desc,
struct reset_controller_dev *rcdev, struct regmap *regmap)
{
int i, ret;
struct genpd_onecell_data *data;
+ struct device *dev = desc->dev;
+ struct gdsc **scs = desc->scs;
+ size_t num = desc->num;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
@@ -228,10 +259,30 @@ int gdsc_register(struct device *dev, struct gdsc **scs, size_t num,
data->domains[i] = &scs[i]->pd;
}
+ /* Add subdomains */
+ for (i = 0; i < num; i++) {
+ if (!scs[i])
+ continue;
+ if (scs[i]->parent)
+ pm_genpd_add_subdomain(scs[i]->parent, &scs[i]->pd);
+ }
+
return of_genpd_add_provider_onecell(dev->of_node, data);
}
-void gdsc_unregister(struct device *dev)
+void gdsc_unregister(struct gdsc_desc *desc)
{
+ int i;
+ struct device *dev = desc->dev;
+ struct gdsc **scs = desc->scs;
+ size_t num = desc->num;
+
+ /* Remove subdomains */
+ for (i = 0; i < num; i++) {
+ if (!scs[i])
+ continue;
+ if (scs[i]->parent)
+ pm_genpd_remove_subdomain(scs[i]->parent, &scs[i]->pd);
+ }
of_genpd_del_provider(dev->of_node);
}