diff options
Diffstat (limited to 'drivers/soc/fsl/rcpm.c')
| -rw-r--r-- | drivers/soc/fsl/rcpm.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/drivers/soc/fsl/rcpm.c b/drivers/soc/fsl/rcpm.c new file mode 100644 index 000000000..3d0cae30c --- /dev/null +++ b/drivers/soc/fsl/rcpm.c @@ -0,0 +1,199 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// rcpm.c - Freescale QorIQ RCPM driver +// +// Copyright 2019-2020 NXP +// +// Author: Ran Wang <ran.wang_1@nxp.com> + +#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> +#include <linux/acpi.h> + +#define RCPM_WAKEUP_CELL_MAX_SIZE 7 + +struct rcpm { + unsigned int wakeup_cells; + void __iomem *ippdexpcr_base; + bool little_endian; +}; + +#define SCFG_SPARECR8 0x051c + +static void copy_ippdexpcr1_setting(u32 val) +{ + struct device_node *np; + void __iomem *regs; + u32 reg_val; + + np = of_find_compatible_node(NULL, NULL, "fsl,ls1021a-scfg"); + if (!np) + return; + + regs = of_iomap(np, 0); + if (!regs) + return; + + reg_val = ioread32be(regs + SCFG_SPARECR8); + iowrite32be(val | reg_val, regs + SCFG_SPARECR8); + + iounmap(regs); +} + +/** + * rcpm_pm_prepare - performs device-level tasks associated with power + * management, such as programming related to the wakeup source control. + * @dev: Device to handle. + * + */ +static int rcpm_pm_prepare(struct device *dev) +{ + int i, ret, idx; + void __iomem *base; + struct wakeup_source *ws; + struct rcpm *rcpm; + struct device_node *np = dev->of_node; + u32 value[RCPM_WAKEUP_CELL_MAX_SIZE + 1]; + u32 setting[RCPM_WAKEUP_CELL_MAX_SIZE] = {0}; + + rcpm = dev_get_drvdata(dev); + if (!rcpm) + return -EINVAL; + + base = rcpm->ippdexpcr_base; + idx = wakeup_sources_read_lock(); + + /* Begin with first registered wakeup source */ + for_each_wakeup_source(ws) { + + /* skip object which is not attached to device */ + if (!ws->dev || !ws->dev->parent) + continue; + + ret = device_property_read_u32_array(ws->dev->parent, + "fsl,rcpm-wakeup", value, + rcpm->wakeup_cells + 1); + + if (ret) + continue; + + /* + * For DT mode, would handle devices with "fsl,rcpm-wakeup" + * pointing to the current RCPM node. + * + * For ACPI mode, currently we assume there is only one + * RCPM controller existing. + */ + if (is_of_node(dev->fwnode)) + if (np->phandle != value[0]) + continue; + + /* Property "#fsl,rcpm-wakeup-cells" of rcpm node defines the + * number of IPPDEXPCR register cells, and "fsl,rcpm-wakeup" + * of wakeup source IP contains an integer array: <phandle to + * RCPM node, IPPDEXPCR0 setting, IPPDEXPCR1 setting, + * IPPDEXPCR2 setting, etc>. + * + * So we will go thought them to collect setting data. + */ + for (i = 0; i < rcpm->wakeup_cells; i++) + setting[i] |= value[i + 1]; + } + + wakeup_sources_read_unlock(idx); + + /* Program all IPPDEXPCRn once */ + for (i = 0; i < rcpm->wakeup_cells; i++) { + u32 tmp = setting[i]; + void __iomem *address = base + i * 4; + + if (!tmp) + continue; + + /* We can only OR related bits */ + if (rcpm->little_endian) { + tmp |= ioread32(address); + iowrite32(tmp, address); + } else { + tmp |= ioread32be(address); + iowrite32be(tmp, address); + } + /* + * Workaround of errata A-008646 on SoC LS1021A: + * There is a bug of register ippdexpcr1. + * Reading configuration register RCPM_IPPDEXPCR1 + * always return zero. So save ippdexpcr1's value + * to register SCFG_SPARECR8.And the value of + * ippdexpcr1 will be read from SCFG_SPARECR8. + */ + if (dev_of_node(dev) && (i == 1)) + if (of_device_is_compatible(np, "fsl,ls1021a-rcpm")) + copy_ippdexpcr1_setting(tmp); + } + + 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 rcpm *rcpm; + int ret; + + rcpm = devm_kzalloc(dev, sizeof(*rcpm), GFP_KERNEL); + if (!rcpm) + return -ENOMEM; + + rcpm->ippdexpcr_base = devm_platform_ioremap_resource(pdev, 0); + 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); + +#ifdef CONFIG_ACPI +static const struct acpi_device_id rcpm_acpi_ids[] = { + {"NXP0015",}, + { } +}; +MODULE_DEVICE_TABLE(acpi, rcpm_acpi_ids); +#endif + +static struct platform_driver rcpm_driver = { + .driver = { + .name = "rcpm", + .of_match_table = rcpm_of_match, + .acpi_match_table = ACPI_PTR(rcpm_acpi_ids), + .pm = &rcpm_pm_ops, + }, + .probe = rcpm_probe, +}; + +module_platform_driver(rcpm_driver); |