[U-Boot] [PATCH v3 8/9] power: domain: ti_sci_power_domains: Add support for exclusive and shared access

[Lokesh Vutla]

TISCI protocol supports for enabling the device either with exclusive
permissions for the requesting host or with sharing across the hosts.
There are certain devices which are exclusive to Linux context and
there are certain devices that are shared across different host contexts.
So add support for getting this information from DT by increasing
the power-domain cells to 2.

For keeping the DT backward compatibility intact, defaulting the
device permissions to set the exclusive flag set. In this case the
power-domain-cells is 1.

Signed-off-by: Lokesh Vutla <lokeshvutla at ti.com>
---
 drivers/power/domain/ti-sci-power-domain.c | 31 +++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

diff --git a/drivers/power/domain/ti-sci-power-domain.c b/drivers/power/domain/ti-sci-power-domain.c
index aafde62cbf..b9cd37b612 100644
--- a/drivers/power/domain/ti-sci-power-domain.c
+++ b/drivers/power/domain/ti-sci-power-domain.c
@@ -13,6 +13,7 @@
 #include <errno.h>
 #include <power-domain-uclass.h>
 #include <linux/soc/ti/ti_sci_protocol.h>
+#include <dt-bindings/soc/ti,sci_pm_domain.h>
 
 /**
  * struct ti_sci_power_domain_data - pm domain controller information structure
@@ -56,11 +57,16 @@ static int ti_sci_power_domain_on(struct power_domain *pd)
 	struct ti_sci_power_domain_data *data = dev_get_priv(pd->dev);
 	const struct ti_sci_handle *sci = data->sci;
 	const struct ti_sci_dev_ops *dops = &sci->ops.dev_ops;
+	u8 flags = (uintptr_t)pd->priv;
 	int ret;
 
 	debug("%s(pd=%p)\n", __func__, pd);
 
-	ret = dops->get_device(sci, pd->id);
+	if (flags & TI_SCI_PD_EXCLUSIVE)
+		ret = dops->get_device_exclusive(sci, pd->id);
+	else
+		ret = dops->get_device(sci, pd->id);
+
 	if (ret)
 		dev_err(power_domain->dev, "%s: get_device failed (%d)\n",
 			__func__, ret);
@@ -85,6 +91,28 @@ static int ti_sci_power_domain_off(struct power_domain *pd)
 	return ret;
 }
 
+static int ti_sci_power_domain_of_xlate(struct power_domain *pd,
+					struct ofnode_phandle_args *args)
+{
+	u8 flags;
+
+	debug("%s(power_domain=%p)\n", __func__, pd);
+
+	if (args->args_count < 1) {
+		debug("Invalid args_count: %d\n", args->args_count);
+		return -EINVAL;
+	}
+
+	pd->id = args->args[0];
+	/* By default request for device exclusive */
+	flags = TI_SCI_PD_EXCLUSIVE;
+	if (args->args_count == 2)
+		flags = args->args[1] & TI_SCI_PD_EXCLUSIVE;
+	pd->priv = (void *)(uintptr_t)flags;
+
+	return 0;
+}
+
 static const struct udevice_id ti_sci_power_domain_of_match[] = {
 	{ .compatible = "ti,sci-pm-domain" },
 	{ /* sentinel */ }
@@ -95,6 +123,7 @@ static struct power_domain_ops ti_sci_power_domain_ops = {
 	.free = ti_sci_power_domain_free,
 	.on = ti_sci_power_domain_on,
 	.off = ti_sci_power_domain_off,
+	.of_xlate = ti_sci_power_domain_of_xlate,
 };
 
 U_BOOT_DRIVER(ti_sci_pm_domains) = {
-- 
2.21.0