[RFC PATCH 2/4] ARM: keystone: pm: switch to use generic pm domains
Grygorii Strashko
grygorii.strashko at ti.com
Thu Sep 25 08:05:35 PDT 2014
This patch switches Keystone 2 PM code to use Generic PM domains
instead of PM clock domains because of the lack of DT support
for the last.
Keystone 2 PM domain should be specified per device for which
Runtime PM has to be enabled and handles the list of functional clocks
to enable/disable device.
Example:
qmss_domain: qmss_pm_controller {
compatible = "ti,keystone-pm-controller";
clocks = <&chipclk13>;
#power-domain-cells = <0>;
};
qmss: qmss at 2a40000 {
compatible = "ti,keystone-navigator-qmss";
...
power-domains = <&qmss_domain>;
Signed-off-by: Grygorii Strashko <grygorii.strashko at ti.com>
---
.../devicetree/bindings/power/ti,keystone-gpc.txt | 37 +++++++
arch/arm/mach-keystone/Kconfig | 1 +
arch/arm/mach-keystone/pm_domain.c | 123 ++++++++++++++++++++-
3 files changed, 158 insertions(+), 3 deletions(-)
create mode 100644 Documentation/devicetree/bindings/power/ti,keystone-gpc.txt
diff --git a/Documentation/devicetree/bindings/power/ti,keystone-gpc.txt b/Documentation/devicetree/bindings/power/ti,keystone-gpc.txt
new file mode 100644
index 0000000..adf63fb
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/ti,keystone-gpc.txt
@@ -0,0 +1,37 @@
+* TI Keystone 2 Generic PM Controller
+
+The TI Keystone 2 Generic PM Controller is responsible for Clock gating
+for each controlled IP module.
+
+Required properties:
+- compatible: Should be "ti,keystone-gpc"
+- clocks: Clock's phandles to devices in the power domain that need
+ to be enabled during domain power-up/down.
+- #power-domain-cells: Should be 0, see below:
+
+The gpc node is a power-controller as documented by the generic power domain
+bindings in Documentation/devicetree/bindings/power/power_domain.txt.
+
+The IP module is allowed to reuse clocks controlled by its power domain
+controller for internal proposes (get current clock rate for example).
+
+Example:
+
+ netcp_domain: netcp_pm_controller {
+ compatible = "ti,keystone-pm-controller";
+ clocks = <&clkpa>, <&clkcpgmac>, <&chipclk12>;
+ #power-domain-cells = <0>;
+ };
+
+ netcp: netcp at 2090000 {
+ reg = <0x2620110 0x8>;
+ reg-names = "efuse";
+ ...
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+ power-domains = <&netcp_domain>;
+
+ clocks = <&clkpa>, <&clkcpgmac>, <&chipclk12>;
+ dma-coherent;
+ }
diff --git a/arch/arm/mach-keystone/Kconfig b/arch/arm/mach-keystone/Kconfig
index e571084..0132bde 100644
--- a/arch/arm/mach-keystone/Kconfig
+++ b/arch/arm/mach-keystone/Kconfig
@@ -9,6 +9,7 @@ config ARCH_KEYSTONE
select COMMON_CLK_KEYSTONE
select ARCH_SUPPORTS_BIG_ENDIAN
select ZONE_DMA if ARM_LPAE
+ select PM_GENERIC_DOMAINS if PM
help
Support for boards based on the Texas Instruments Keystone family of
SoCs.
diff --git a/arch/arm/mach-keystone/pm_domain.c b/arch/arm/mach-keystone/pm_domain.c
index ca79dda..3cf6696 100644
--- a/arch/arm/mach-keystone/pm_domain.c
+++ b/arch/arm/mach-keystone/pm_domain.c
@@ -12,14 +12,17 @@
* version 2, as published by the Free Software Foundation.
*/
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
#include <linux/init.h>
#include <linux/pm_runtime.h>
#include <linux/pm_clock.h>
+#include <linux/pm_domain.h>
#include <linux/platform_device.h>
-#include <linux/clk-provider.h>
#include <linux/of.h>
#ifdef CONFIG_PM_RUNTIME
+
static int keystone_pm_runtime_suspend(struct device *dev)
{
int ret;
@@ -66,6 +69,118 @@ static struct of_device_id of_keystone_table[] = {
{ /* end of list */ },
};
+#ifdef CONFIG_PM_GENERIC_DOMAINS
+
+struct keystone_domain {
+ struct generic_pm_domain base;
+ struct device *dev;
+};
+
+static int keystone_pm_domain_power_off(struct generic_pm_domain *genpd)
+{
+ int ret;
+ struct keystone_domain *dm = container_of(genpd,
+ struct keystone_domain,
+ base);
+
+ /* Enable reset clocks for all devices in the PU domain */
+ ret = pm_clk_suspend(dm->dev);
+ if (ret)
+ dev_err(dm->dev, "can't turn off clocks %d\n", ret);
+
+ return ret;
+}
+
+static int keystone_pm_domain_power_on(struct generic_pm_domain *genpd)
+{
+ int ret;
+ struct keystone_domain *dm = container_of(genpd,
+ struct keystone_domain,
+ base);
+
+ /* Disable reset clocks for all devices in the PU domain */
+ ret = pm_clk_resume(dm->dev);
+ if (ret)
+ dev_err(dm->dev, "can't turn on clocks %d\n", ret);
+
+ return ret;
+}
+
+static const struct keystone_domain keystone_domain = {
+ .base = {
+ .name = "keystone",
+ .power_off = keystone_pm_domain_power_off,
+ .power_on = keystone_pm_domain_power_on,
+ .power_off_latency_ns = 25000,
+ .power_on_latency_ns = 2000000,
+ },
+};
+
+static int keystone_pm_domain_probe(struct platform_device *pdev)
+{
+ struct clk *clk;
+ bool is_off;
+ int i = 0;
+ struct keystone_domain *domain;
+ int ret = 0;
+
+ domain = devm_kzalloc(&pdev->dev,
+ sizeof(struct keystone_domain), GFP_KERNEL);
+ if (!domain)
+ return -ENOMEM;
+
+ domain->base = keystone_domain.base;
+ domain->base.of_node = pdev->dev.of_node;
+ domain->dev = &pdev->dev;
+
+ ret = pm_clk_create(&pdev->dev);
+ if (ret) {
+ dev_err(&pdev->dev, "pm_clk_create failed %d\n", ret);
+ return ret;
+ };
+
+ while ((clk = of_clk_get(pdev->dev.of_node, i++)) && !IS_ERR(clk)) {
+ ret = pm_clk_add_clk(&pdev->dev, clk);
+ if (ret) {
+ dev_err(&pdev->dev, "pm_clk_add_clk failed %d\n", ret);
+ goto clk_err;
+ };
+ }
+
+ is_off = IS_ENABLED(CONFIG_PM_RUNTIME);
+ if (is_off)
+ keystone_pm_domain_power_off(&domain->base);
+
+ pm_genpd_init(&domain->base, NULL, is_off);
+ return of_genpd_add_provider_simple(pdev->dev.of_node, &domain->base);
+
+clk_err:
+ pm_clk_destroy(&pdev->dev);
+ return ret;
+}
+
+static struct of_device_id keystone_pm_domain_dt_ids[] = {
+ { .compatible = "ti,keystone-gpc" },
+ { }
+};
+
+static struct platform_driver keystone_pm_domain_driver = {
+ .driver = {
+ .name = "ti,keystone-gpc",
+ .owner = THIS_MODULE,
+ .of_match_table = keystone_pm_domain_dt_ids,
+ },
+ .probe = keystone_pm_domain_probe,
+};
+
+static int __init keystone_pm_domain_init(void)
+{
+ return platform_driver_register(&keystone_pm_domain_driver);
+}
+#else
+static int __init keystone_pm_domain_init(void) { return 0; }
+#endif /* CONFIG_PM_GENERIC_DOMAINS */
+
int __init keystone_pm_runtime_init(void)
{
struct device_node *np;
@@ -74,7 +189,9 @@ int __init keystone_pm_runtime_init(void)
if (!np)
return 0;
- pm_clk_add_notifier(&platform_bus_type, &platform_domain_notifier);
+ /* TODO: remove clock_ops code
+ * pm_clk_add_notifier(&platform_bus_type, &platform_domain_notifier);
+ */
- return 0;
+ return keystone_pm_domain_init();
}
--
1.9.1
More information about the linux-arm-kernel
mailing list