[PATCH v4 3/3] soc: fsl: add RCPM driver

From: Ran Wang
Date: Mon May 20 2019 - 05:53:29 EST


The NXP's QorIQ Processors based on ARM Core have RCPM module
(Run Control and Power Management), which performs all device-level
tasks associated with power management such as wakeup source control.

This driver depends on PM wakeup source framework which help to
collect wake information.

Signed-off-by: Ran Wang <ran.wang_1@xxxxxxx>
Acked-by: Pavel Machek <pavel@xxxxxx>
---
Change in v4:
- Remove extra ',' in author line of rcpm.c
- Update usage of wakeup_source_get_next() to be less confusing to the
reader, code logic remain the same.

Change in v3:
- Some whitespace ajdustment.

Change in v2:
- Rebase Kconfig and Makefile update to latest mainline.

drivers/soc/fsl/Kconfig | 8 +++
drivers/soc/fsl/Makefile | 1 +
drivers/soc/fsl/rcpm.c | 122 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 131 insertions(+), 0 deletions(-)
create mode 100644 drivers/soc/fsl/rcpm.c

diff --git a/drivers/soc/fsl/Kconfig b/drivers/soc/fsl/Kconfig
index 61f8e14..8e84e40 100644
--- a/drivers/soc/fsl/Kconfig
+++ b/drivers/soc/fsl/Kconfig
@@ -29,4 +29,12 @@ config FSL_MC_DPIO
other DPAA2 objects. This driver does not expose the DPIO
objects individually, but groups them under a service layer
API.
+
+config FSL_RCPM
+ bool "Freescale RCPM support"
+ depends on PM_SLEEP
+ help
+ The NXP's QorIQ Processors based on ARM Core have RCPM module
+ (Run Control and Power Management), which performs all device-level
+ tasks associated with power management, such as wakeup source control.
endmenu
diff --git a/drivers/soc/fsl/Makefile b/drivers/soc/fsl/Makefile
index 803ef1b..c1be6ee 100644
--- a/drivers/soc/fsl/Makefile
+++ b/drivers/soc/fsl/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_QUICC_ENGINE) += qe/
obj-$(CONFIG_CPM) += qe/
obj-$(CONFIG_FSL_GUTS) += guts.o
obj-$(CONFIG_FSL_MC_DPIO) += dpio/
+obj-$(CONFIG_FSL_RCPM) += rcpm.o
diff --git a/drivers/soc/fsl/rcpm.c b/drivers/soc/fsl/rcpm.c
new file mode 100644
index 0000000..ff27adc
--- /dev/null
+++ b/drivers/soc/fsl/rcpm.c
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// rcpm.c - Freescale QorIQ RCPM driver
+//
+// Copyright 2019 NXP
+//
+// Author: Ran Wang <ran.wang_1@xxxxxxx>
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <linux/suspend.h>
+#include <linux/kernel.h>
+
+#define RCPM_WAKEUP_CELL_MAX_SIZE 7
+
+struct rcpm {
+ unsigned int wakeup_cells;
+ void __iomem *ippdexpcr_base;
+ bool little_endian;
+};
+
+static int rcpm_pm_prepare(struct device *dev)
+{
+ struct device_node *np = dev->of_node;
+ struct wakeup_source *ws;
+ struct rcpm *rcpm;
+ u32 value[RCPM_WAKEUP_CELL_MAX_SIZE + 1], tmp;
+ int i, ret;
+
+ rcpm = dev_get_drvdata(dev);
+ if (!rcpm)
+ return -EINVAL;
+
+ /* Begin with first registered wakeup source */
+ ws = NULL;
+ while (wakeup_source_get_next(ws)) {
+ ret = device_property_read_u32_array(ws->attached_dev,
+ "fsl,rcpm-wakeup", value, rcpm->wakeup_cells + 1);
+
+ /* Wakeup source should refer to current rcpm device */
+ if (ret || (np->phandle != value[0])) {
+ dev_info(dev, "%s doesn't refer to this rcpm\n",
+ ws->name);
+ continue;
+ }
+
+ for (i = 0; i < rcpm->wakeup_cells; i++) {
+ /* We can only OR related bits */
+ if (value[i + 1]) {
+ if (rcpm->little_endian) {
+ tmp = ioread32(rcpm->ippdexpcr_base + i * 4);
+ tmp |= value[i + 1];
+ iowrite32(tmp, rcpm->ippdexpcr_base + i * 4);
+ } else {
+ tmp = ioread32be(rcpm->ippdexpcr_base + i * 4);
+ tmp |= value[i + 1];
+ iowrite32be(tmp, rcpm->ippdexpcr_base + i * 4);
+ }
+ }
+ }
+ }
+
+ return 0;
+}
+
+static const struct dev_pm_ops rcpm_pm_ops = {
+ .prepare = rcpm_pm_prepare,
+};
+
+static int rcpm_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *r;
+ struct rcpm *rcpm;
+ int ret;
+
+ rcpm = devm_kzalloc(dev, sizeof(*rcpm), GFP_KERNEL);
+ if (!rcpm)
+ return -ENOMEM;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!r)
+ return -ENODEV;
+
+ rcpm->ippdexpcr_base = devm_ioremap_resource(&pdev->dev, r);
+ if (IS_ERR(rcpm->ippdexpcr_base)) {
+ ret = PTR_ERR(rcpm->ippdexpcr_base);
+ return ret;
+ }
+
+ rcpm->little_endian = device_property_read_bool(
+ &pdev->dev, "little-endian");
+
+ ret = device_property_read_u32(&pdev->dev,
+ "fsl,#rcpm-wakeup-cells", &rcpm->wakeup_cells);
+ if (ret)
+ return ret;
+
+ dev_set_drvdata(&pdev->dev, rcpm);
+
+ return 0;
+}
+
+static const struct of_device_id rcpm_of_match[] = {
+ { .compatible = "fsl,qoriq-rcpm-2.1+", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, rcpm_of_match);
+
+static struct platform_driver rcpm_driver = {
+ .driver = {
+ .name = "rcpm",
+ .of_match_table = rcpm_of_match,
+ .pm = &rcpm_pm_ops,
+ },
+ .probe = rcpm_probe,
+};
+
+module_platform_driver(rcpm_driver);
--
1.7.1