| Message ID | 1407872640-6732-9-git-send-email-lina.iyer@linaro.org (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On 08/12/2014 09:43 PM, Lina Iyer wrote: > Add cpuidle driver interface to allow cpus to go into C-States. > > Signed-off-by: Lina Iyer <lina.iyer@linaro.org> Hi Lina, I think you should based this driver on top of Lorenzo's work. Cc Lorenzo. > --- > .../devicetree/bindings/arm/msm/qcom,cpuidle.txt | 73 +++++++++++ > drivers/cpuidle/Makefile | 1 + > drivers/cpuidle/cpuidle-qcom.c | 140 +++++++++++++++++++++ > 3 files changed, 214 insertions(+) > create mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt > create mode 100644 drivers/cpuidle/cpuidle-qcom.c > > diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt b/Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt > new file mode 100644 > index 0000000..b094baf > --- /dev/null > +++ b/Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt > @@ -0,0 +1,73 @@ > +Qualcomm CPUIdle driver > + > +The Qualcomm cpuidle driver enables the processor to enter low power modes > +when idle. The processors support 4 low power modes. > + wfi - also known as clock gating > + retention - processor clock gated and processor power is reduced. > + standalone-pc - processor is powered down and when reset, the core > + boots into secure mode and trampolines back to the kernel. > + Every core can individually enter this low power mode without > + affecting the state of the other cores. > + pc - essentially standalone power collapse, but indicates that the > + latency to put SoC into a low power state is tolerable. > + > +The cpuidle node is comprised of nodes, each of which represent a C-State the > +processor can achieve. Each node provides the latency and residency which > +helps the cpuidle governor to choose the appropriate low power mode based on > +the time available. Not all SoCs may support all the above low power modes. > + > +PROPERTIES > + > +- compatible: > + Usage: required > + Value type: <string> > + Definition: Should be "qcom,cpuidle" > + > +- qcom,cpu-level: > + Usage: required > + Value type: { Node } > + Definition: Describes a C-State of the processor > + > + PROPERTIES of qcom,cpu-level > + > + - reg: > + Usage: required > + Value type: <integer> > + Definition: Index of the C-State > + > + - qcom,state-name: > + Usage: required > + Value type: <string> > + Definition: C-State moniker > + > + - qcom,spm-cpu-mode: > + Usage: required > + Value type: <string> > + Definition: The description of the h/w mode that will be > + achieved in this C-State. > + > + - qcom,latency-us: > + Usage: required > + Value type: <integer> > + Defintion: Time taken to exit from the C-State > + > + - qcom,residency-us: > + Usage: required > + Value type: <integer> > + Defintion: Time to be spent in this C-State for the power > + saving to be beneficial. > + > +Example: > + > + qcom,cpuidle { > + compatible = "qcom,cpuidle"; > + #address-cells = <1>; > + #size-cells = <0>; > + qcom,cpu-level@0 { > + reg = <0x0>; > + qcom,state-name = "C1"; > + qcom,spm-cpu-mode = "wfi"; > + qcom,latency-us = <1>; > + qcom,residency-us = <1>; > + }; > + }; > diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile > index 11edb31..4a2c446 100644 > --- a/drivers/cpuidle/Makefile > +++ b/drivers/cpuidle/Makefile > @@ -16,6 +16,7 @@ obj-$(CONFIG_ARM_ZYNQ_CPUIDLE) += cpuidle-zynq.o > obj-$(CONFIG_ARM_U8500_CPUIDLE) += cpuidle-ux500.o > obj-$(CONFIG_ARM_AT91_CPUIDLE) += cpuidle-at91.o > obj-$(CONFIG_ARM_EXYNOS_CPUIDLE) += cpuidle-exynos.o > +obj-$(CONFIG_ARM_QCOM_CPUIDLE) += cpuidle-qcom.o > > ############################################################################### > # MIPS drivers > diff --git a/drivers/cpuidle/cpuidle-qcom.c b/drivers/cpuidle/cpuidle-qcom.c > new file mode 100644 > index 0000000..8e70a88 > --- /dev/null > +++ b/drivers/cpuidle/cpuidle-qcom.c > @@ -0,0 +1,140 @@ > +/* Copyright (c) 2014, The Linux Foundation. All rights reserved. > + * Copyright (c) 2014 Linaro. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 and > + * only version 2 as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + */ > + > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/of.h> > +#include <linux/cpuidle.h> > + > +#include <soc/qcom/pm.h> > + > +struct lookup { > + enum msm_pm_sleep_mode mode; > + char *name; > +}; > + > +static enum msm_pm_sleep_mode spm_sleep_modes[MSM_PM_SLEEP_MODE_NR]; > + > +static int qcom_lpm_enter(struct cpuidle_device *dev, > + struct cpuidle_driver *drv, > + int index) > +{ > + return msm_cpu_pm_enter_sleep(spm_sleep_modes[index], true); > +} > + > +static struct cpuidle_driver qcom_cpuidle_driver = { > + .name = "qcom_cpuidle", > + .owner = THIS_MODULE, > +}; > + > +static int qcom_cpuidle_probe(struct platform_device *pdev) > +{ > + int ret; > + struct device_node *top = pdev->dev.of_node; > + struct device_node *n; > + char *key; > + const char *val; > + int index = 0; > + int i; > + struct cpuidle_state *state; > + static const struct lookup pm_sm_lookup[] = { > + {MSM_PM_SLEEP_MODE_WAIT_FOR_INTERRUPT, > + "wfi"}, > + {MSM_PM_SLEEP_MODE_POWER_COLLAPSE_STANDALONE, > + "standalone_pc"}, > + {MSM_PM_SLEEP_MODE_POWER_COLLAPSE, > + "pc"}, > + {MSM_PM_SLEEP_MODE_RETENTION, > + "retention"}, > + }; > + > + if (!top) > + return -ENODEV; > + > + for_each_child_of_node(top, n) { > + key = "qcom,cpu-level"; > + if (of_node_cmp(n->name, key)) > + continue; > + > + state = &qcom_cpuidle_driver.states[index]; > + > + key = "qcom,spm-cpu-mode"; > + ret = of_property_read_string(n, key, &val); > + if (ret) > + goto failed; > + for (i = 0; i < ARRAY_SIZE(pm_sm_lookup); i++) { > + if (!strcmp(val, pm_sm_lookup[i].name)) { > + spm_sleep_modes[index] = pm_sm_lookup[i].mode; > + break; > + } > + } > + if (i == ARRAY_SIZE(pm_sm_lookup)) { > + ret = -EFAULT; > + goto failed; > + } > + > + strncpy(state->desc, val, CPUIDLE_DESC_LEN); > + > + key = "qcom,state-name"; > + ret = of_property_read_string(n, key, &val); > + if (ret) > + goto failed; > + strncpy(state->name, val, CPUIDLE_NAME_LEN); > + > + key = "qcom,latency-us"; > + ret = of_property_read_u32(n, key, &state->exit_latency); > + if (ret) > + goto failed; > + > + key = "qcom,residency-us"; > + ret = of_property_read_u32(n, key, &state->target_residency); > + if (ret) > + goto failed; > + > + state->flags = CPUIDLE_FLAG_TIME_VALID; > + state->enter = qcom_lpm_enter; > + index++; > + } > + > + qcom_cpuidle_driver.state_count = index; > + qcom_cpuidle_driver.safe_state_index = 0; > + > + ret = cpuidle_register(&qcom_cpuidle_driver, NULL); > + if (ret) { > + dev_err(&pdev->dev, "failed to register cpuidle driver\n"); > + return ret; > + } > + > + return 0; > + > +failed: > + dev_err(&pdev->dev, "error parsing key: %s\n", key); > + return ret; > +} > + > +static struct of_device_id qcom_cpuidle_match_tbl[] = { > + {.compatible = "qcom,cpuidle"}, > + {}, > +}; > + > +static struct platform_driver qcom_cpuidle_platform_driver = { > + .probe = qcom_cpuidle_probe, > + .driver = { > + .name = "qcom,cpuidle", > + .owner = THIS_MODULE, > + .of_match_table = qcom_cpuidle_match_tbl, > + }, > +}; > + > +module_platform_driver(qcom_cpuidle_platform_driver); >
On Wed, Aug 13, 2014 at 01:22:09PM +0200, Daniel Lezcano wrote: >On 08/12/2014 09:43 PM, Lina Iyer wrote: >>Add cpuidle driver interface to allow cpus to go into C-States. >> >>Signed-off-by: Lina Iyer <lina.iyer@linaro.org> > >Hi Lina, > >I think you should based this driver on top of Lorenzo's work. > >Cc Lorenzo. OK, I wasnt aware of Lorenzo's patches. Stephen B pointed that to me yesterday. Looking at it. Its quite similar to what I have here. I yanked this driver out of the original patch that does both cpuidle and SoCIdle, which does the cluster part of Lorenzo's drivers. -Lina. > >>--- >> .../devicetree/bindings/arm/msm/qcom,cpuidle.txt | 73 +++++++++++ >> drivers/cpuidle/Makefile | 1 + >> drivers/cpuidle/cpuidle-qcom.c | 140 +++++++++++++++++++++ >> 3 files changed, 214 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt >> create mode 100644 drivers/cpuidle/cpuidle-qcom.c >> >>diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt b/Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt >>new file mode 100644 >>index 0000000..b094baf >>--- /dev/null >>+++ b/Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt >>@@ -0,0 +1,73 @@ >>+Qualcomm CPUIdle driver >>+ >>+The Qualcomm cpuidle driver enables the processor to enter low power modes >>+when idle. The processors support 4 low power modes. >>+ wfi - also known as clock gating >>+ retention - processor clock gated and processor power is reduced. >>+ standalone-pc - processor is powered down and when reset, the core >>+ boots into secure mode and trampolines back to the kernel. >>+ Every core can individually enter this low power mode without >>+ affecting the state of the other cores. >>+ pc - essentially standalone power collapse, but indicates that the >>+ latency to put SoC into a low power state is tolerable. >>+ >>+The cpuidle node is comprised of nodes, each of which represent a C-State the >>+processor can achieve. Each node provides the latency and residency which >>+helps the cpuidle governor to choose the appropriate low power mode based on >>+the time available. Not all SoCs may support all the above low power modes. >>+ >>+PROPERTIES >>+ >>+- compatible: >>+ Usage: required >>+ Value type: <string> >>+ Definition: Should be "qcom,cpuidle" >>+ >>+- qcom,cpu-level: >>+ Usage: required >>+ Value type: { Node } >>+ Definition: Describes a C-State of the processor >>+ >>+ PROPERTIES of qcom,cpu-level >>+ >>+ - reg: >>+ Usage: required >>+ Value type: <integer> >>+ Definition: Index of the C-State >>+ >>+ - qcom,state-name: >>+ Usage: required >>+ Value type: <string> >>+ Definition: C-State moniker >>+ >>+ - qcom,spm-cpu-mode: >>+ Usage: required >>+ Value type: <string> >>+ Definition: The description of the h/w mode that will be >>+ achieved in this C-State. >>+ >>+ - qcom,latency-us: >>+ Usage: required >>+ Value type: <integer> >>+ Defintion: Time taken to exit from the C-State >>+ >>+ - qcom,residency-us: >>+ Usage: required >>+ Value type: <integer> >>+ Defintion: Time to be spent in this C-State for the power >>+ saving to be beneficial. >>+ >>+Example: >>+ >>+ qcom,cpuidle { >>+ compatible = "qcom,cpuidle"; >>+ #address-cells = <1>; >>+ #size-cells = <0>; >>+ qcom,cpu-level@0 { >>+ reg = <0x0>; >>+ qcom,state-name = "C1"; >>+ qcom,spm-cpu-mode = "wfi"; >>+ qcom,latency-us = <1>; >>+ qcom,residency-us = <1>; >>+ }; >>+ }; >>diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile >>index 11edb31..4a2c446 100644 >>--- a/drivers/cpuidle/Makefile >>+++ b/drivers/cpuidle/Makefile >>@@ -16,6 +16,7 @@ obj-$(CONFIG_ARM_ZYNQ_CPUIDLE) += cpuidle-zynq.o >> obj-$(CONFIG_ARM_U8500_CPUIDLE) += cpuidle-ux500.o >> obj-$(CONFIG_ARM_AT91_CPUIDLE) += cpuidle-at91.o >> obj-$(CONFIG_ARM_EXYNOS_CPUIDLE) += cpuidle-exynos.o >>+obj-$(CONFIG_ARM_QCOM_CPUIDLE) += cpuidle-qcom.o >> >> ############################################################################### >> # MIPS drivers >>diff --git a/drivers/cpuidle/cpuidle-qcom.c b/drivers/cpuidle/cpuidle-qcom.c >>new file mode 100644 >>index 0000000..8e70a88 >>--- /dev/null >>+++ b/drivers/cpuidle/cpuidle-qcom.c >>@@ -0,0 +1,140 @@ >>+/* Copyright (c) 2014, The Linux Foundation. All rights reserved. >>+ * Copyright (c) 2014 Linaro. >>+ * >>+ * This program is free software; you can redistribute it and/or modify >>+ * it under the terms of the GNU General Public License version 2 and >>+ * only version 2 as published by the Free Software Foundation. >>+ * >>+ * This program is distributed in the hope that it will be useful, >>+ * but WITHOUT ANY WARRANTY; without even the implied warranty of >>+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >>+ * GNU General Public License for more details. >>+ * >>+ */ >>+ >>+#include <linux/module.h> >>+#include <linux/platform_device.h> >>+#include <linux/of.h> >>+#include <linux/cpuidle.h> >>+ >>+#include <soc/qcom/pm.h> >>+ >>+struct lookup { >>+ enum msm_pm_sleep_mode mode; >>+ char *name; >>+}; >>+ >>+static enum msm_pm_sleep_mode spm_sleep_modes[MSM_PM_SLEEP_MODE_NR]; >>+ >>+static int qcom_lpm_enter(struct cpuidle_device *dev, >>+ struct cpuidle_driver *drv, >>+ int index) >>+{ >>+ return msm_cpu_pm_enter_sleep(spm_sleep_modes[index], true); >>+} >>+ >>+static struct cpuidle_driver qcom_cpuidle_driver = { >>+ .name = "qcom_cpuidle", >>+ .owner = THIS_MODULE, >>+}; >>+ >>+static int qcom_cpuidle_probe(struct platform_device *pdev) >>+{ >>+ int ret; >>+ struct device_node *top = pdev->dev.of_node; >>+ struct device_node *n; >>+ char *key; >>+ const char *val; >>+ int index = 0; >>+ int i; >>+ struct cpuidle_state *state; >>+ static const struct lookup pm_sm_lookup[] = { >>+ {MSM_PM_SLEEP_MODE_WAIT_FOR_INTERRUPT, >>+ "wfi"}, >>+ {MSM_PM_SLEEP_MODE_POWER_COLLAPSE_STANDALONE, >>+ "standalone_pc"}, >>+ {MSM_PM_SLEEP_MODE_POWER_COLLAPSE, >>+ "pc"}, >>+ {MSM_PM_SLEEP_MODE_RETENTION, >>+ "retention"}, >>+ }; >>+ >>+ if (!top) >>+ return -ENODEV; >>+ >>+ for_each_child_of_node(top, n) { >>+ key = "qcom,cpu-level"; >>+ if (of_node_cmp(n->name, key)) >>+ continue; >>+ >>+ state = &qcom_cpuidle_driver.states[index]; >>+ >>+ key = "qcom,spm-cpu-mode"; >>+ ret = of_property_read_string(n, key, &val); >>+ if (ret) >>+ goto failed; >>+ for (i = 0; i < ARRAY_SIZE(pm_sm_lookup); i++) { >>+ if (!strcmp(val, pm_sm_lookup[i].name)) { >>+ spm_sleep_modes[index] = pm_sm_lookup[i].mode; >>+ break; >>+ } >>+ } >>+ if (i == ARRAY_SIZE(pm_sm_lookup)) { >>+ ret = -EFAULT; >>+ goto failed; >>+ } >>+ >>+ strncpy(state->desc, val, CPUIDLE_DESC_LEN); >>+ >>+ key = "qcom,state-name"; >>+ ret = of_property_read_string(n, key, &val); >>+ if (ret) >>+ goto failed; >>+ strncpy(state->name, val, CPUIDLE_NAME_LEN); >>+ >>+ key = "qcom,latency-us"; >>+ ret = of_property_read_u32(n, key, &state->exit_latency); >>+ if (ret) >>+ goto failed; >>+ >>+ key = "qcom,residency-us"; >>+ ret = of_property_read_u32(n, key, &state->target_residency); >>+ if (ret) >>+ goto failed; >>+ >>+ state->flags = CPUIDLE_FLAG_TIME_VALID; >>+ state->enter = qcom_lpm_enter; >>+ index++; >>+ } >>+ >>+ qcom_cpuidle_driver.state_count = index; >>+ qcom_cpuidle_driver.safe_state_index = 0; >>+ >>+ ret = cpuidle_register(&qcom_cpuidle_driver, NULL); >>+ if (ret) { >>+ dev_err(&pdev->dev, "failed to register cpuidle driver\n"); >>+ return ret; >>+ } >>+ >>+ return 0; >>+ >>+failed: >>+ dev_err(&pdev->dev, "error parsing key: %s\n", key); >>+ return ret; >>+} >>+ >>+static struct of_device_id qcom_cpuidle_match_tbl[] = { >>+ {.compatible = "qcom,cpuidle"}, >>+ {}, >>+}; >>+ >>+static struct platform_driver qcom_cpuidle_platform_driver = { >>+ .probe = qcom_cpuidle_probe, >>+ .driver = { >>+ .name = "qcom,cpuidle", >>+ .owner = THIS_MODULE, >>+ .of_match_table = qcom_cpuidle_match_tbl, >>+ }, >>+}; >>+ >>+module_platform_driver(qcom_cpuidle_platform_driver); >> > > >-- > <http://www.linaro.org/> Linaro.org ? Open source software for ARM SoCs > >Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | ><http://twitter.com/#!/linaroorg> Twitter | ><http://www.linaro.org/linaro-blog/> Blog > -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt b/Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt new file mode 100644 index 0000000..b094baf --- /dev/null +++ b/Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt @@ -0,0 +1,73 @@ +Qualcomm CPUIdle driver + +The Qualcomm cpuidle driver enables the processor to enter low power modes +when idle. The processors support 4 low power modes. + wfi - also known as clock gating + retention - processor clock gated and processor power is reduced. + standalone-pc - processor is powered down and when reset, the core + boots into secure mode and trampolines back to the kernel. + Every core can individually enter this low power mode without + affecting the state of the other cores. + pc - essentially standalone power collapse, but indicates that the + latency to put SoC into a low power state is tolerable. + +The cpuidle node is comprised of nodes, each of which represent a C-State the +processor can achieve. Each node provides the latency and residency which +helps the cpuidle governor to choose the appropriate low power mode based on +the time available. Not all SoCs may support all the above low power modes. + +PROPERTIES + +- compatible: + Usage: required + Value type: <string> + Definition: Should be "qcom,cpuidle" + +- qcom,cpu-level: + Usage: required + Value type: { Node } + Definition: Describes a C-State of the processor + + PROPERTIES of qcom,cpu-level + + - reg: + Usage: required + Value type: <integer> + Definition: Index of the C-State + + - qcom,state-name: + Usage: required + Value type: <string> + Definition: C-State moniker + + - qcom,spm-cpu-mode: + Usage: required + Value type: <string> + Definition: The description of the h/w mode that will be + achieved in this C-State. + + - qcom,latency-us: + Usage: required + Value type: <integer> + Defintion: Time taken to exit from the C-State + + - qcom,residency-us: + Usage: required + Value type: <integer> + Defintion: Time to be spent in this C-State for the power + saving to be beneficial. + +Example: + + qcom,cpuidle { + compatible = "qcom,cpuidle"; + #address-cells = <1>; + #size-cells = <0>; + qcom,cpu-level@0 { + reg = <0x0>; + qcom,state-name = "C1"; + qcom,spm-cpu-mode = "wfi"; + qcom,latency-us = <1>; + qcom,residency-us = <1>; + }; + }; diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile index 11edb31..4a2c446 100644 --- a/drivers/cpuidle/Makefile +++ b/drivers/cpuidle/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_ARM_ZYNQ_CPUIDLE) += cpuidle-zynq.o obj-$(CONFIG_ARM_U8500_CPUIDLE) += cpuidle-ux500.o obj-$(CONFIG_ARM_AT91_CPUIDLE) += cpuidle-at91.o obj-$(CONFIG_ARM_EXYNOS_CPUIDLE) += cpuidle-exynos.o +obj-$(CONFIG_ARM_QCOM_CPUIDLE) += cpuidle-qcom.o ############################################################################### # MIPS drivers diff --git a/drivers/cpuidle/cpuidle-qcom.c b/drivers/cpuidle/cpuidle-qcom.c new file mode 100644 index 0000000..8e70a88 --- /dev/null +++ b/drivers/cpuidle/cpuidle-qcom.c @@ -0,0 +1,140 @@ +/* Copyright (c) 2014, The Linux Foundation. All rights reserved. + * Copyright (c) 2014 Linaro. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/of.h> +#include <linux/cpuidle.h> + +#include <soc/qcom/pm.h> + +struct lookup { + enum msm_pm_sleep_mode mode; + char *name; +}; + +static enum msm_pm_sleep_mode spm_sleep_modes[MSM_PM_SLEEP_MODE_NR]; + +static int qcom_lpm_enter(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + return msm_cpu_pm_enter_sleep(spm_sleep_modes[index], true); +} + +static struct cpuidle_driver qcom_cpuidle_driver = { + .name = "qcom_cpuidle", + .owner = THIS_MODULE, +}; + +static int qcom_cpuidle_probe(struct platform_device *pdev) +{ + int ret; + struct device_node *top = pdev->dev.of_node; + struct device_node *n; + char *key; + const char *val; + int index = 0; + int i; + struct cpuidle_state *state; + static const struct lookup pm_sm_lookup[] = { + {MSM_PM_SLEEP_MODE_WAIT_FOR_INTERRUPT, + "wfi"}, + {MSM_PM_SLEEP_MODE_POWER_COLLAPSE_STANDALONE, + "standalone_pc"}, + {MSM_PM_SLEEP_MODE_POWER_COLLAPSE, + "pc"}, + {MSM_PM_SLEEP_MODE_RETENTION, + "retention"}, + }; + + if (!top) + return -ENODEV; + + for_each_child_of_node(top, n) { + key = "qcom,cpu-level"; + if (of_node_cmp(n->name, key)) + continue; + + state = &qcom_cpuidle_driver.states[index]; + + key = "qcom,spm-cpu-mode"; + ret = of_property_read_string(n, key, &val); + if (ret) + goto failed; + for (i = 0; i < ARRAY_SIZE(pm_sm_lookup); i++) { + if (!strcmp(val, pm_sm_lookup[i].name)) { + spm_sleep_modes[index] = pm_sm_lookup[i].mode; + break; + } + } + if (i == ARRAY_SIZE(pm_sm_lookup)) { + ret = -EFAULT; + goto failed; + } + + strncpy(state->desc, val, CPUIDLE_DESC_LEN); + + key = "qcom,state-name"; + ret = of_property_read_string(n, key, &val); + if (ret) + goto failed; + strncpy(state->name, val, CPUIDLE_NAME_LEN); + + key = "qcom,latency-us"; + ret = of_property_read_u32(n, key, &state->exit_latency); + if (ret) + goto failed; + + key = "qcom,residency-us"; + ret = of_property_read_u32(n, key, &state->target_residency); + if (ret) + goto failed; + + state->flags = CPUIDLE_FLAG_TIME_VALID; + state->enter = qcom_lpm_enter; + index++; + } + + qcom_cpuidle_driver.state_count = index; + qcom_cpuidle_driver.safe_state_index = 0; + + ret = cpuidle_register(&qcom_cpuidle_driver, NULL); + if (ret) { + dev_err(&pdev->dev, "failed to register cpuidle driver\n"); + return ret; + } + + return 0; + +failed: + dev_err(&pdev->dev, "error parsing key: %s\n", key); + return ret; +} + +static struct of_device_id qcom_cpuidle_match_tbl[] = { + {.compatible = "qcom,cpuidle"}, + {}, +}; + +static struct platform_driver qcom_cpuidle_platform_driver = { + .probe = qcom_cpuidle_probe, + .driver = { + .name = "qcom,cpuidle", + .owner = THIS_MODULE, + .of_match_table = qcom_cpuidle_match_tbl, + }, +}; + +module_platform_driver(qcom_cpuidle_platform_driver);
Add cpuidle driver interface to allow cpus to go into C-States. Signed-off-by: Lina Iyer <lina.iyer@linaro.org> --- .../devicetree/bindings/arm/msm/qcom,cpuidle.txt | 73 +++++++++++ drivers/cpuidle/Makefile | 1 + drivers/cpuidle/cpuidle-qcom.c | 140 +++++++++++++++++++++ 3 files changed, 214 insertions(+) create mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,cpuidle.txt create mode 100644 drivers/cpuidle/cpuidle-qcom.c