diff options
Diffstat (limited to 'drivers/soc/xilinx/zynqmp_power.c')
-rw-r--r-- | drivers/soc/xilinx/zynqmp_power.c | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/drivers/soc/xilinx/zynqmp_power.c b/drivers/soc/xilinx/zynqmp_power.c new file mode 100644 index 000000000..c556623da --- /dev/null +++ b/drivers/soc/xilinx/zynqmp_power.c @@ -0,0 +1,263 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Xilinx Zynq MPSoC Power Management + * + * Copyright (C) 2014-2019 Xilinx, Inc. + * + * Davorin Mista <davorin.mista@aggios.com> + * Jolly Shah <jollys@xilinx.com> + * Rajan Vaja <rajan.vaja@xilinx.com> + */ + +#include <linux/mailbox_client.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/reboot.h> +#include <linux/suspend.h> + +#include <linux/firmware/xlnx-zynqmp.h> +#include <linux/mailbox/zynqmp-ipi-message.h> + +/** + * struct zynqmp_pm_work_struct - Wrapper for struct work_struct + * @callback_work: Work structure + * @args: Callback arguments + */ +struct zynqmp_pm_work_struct { + struct work_struct callback_work; + u32 args[CB_ARG_CNT]; +}; + +static struct zynqmp_pm_work_struct *zynqmp_pm_init_suspend_work; +static struct mbox_chan *rx_chan; + +enum pm_suspend_mode { + PM_SUSPEND_MODE_FIRST = 0, + PM_SUSPEND_MODE_STD = PM_SUSPEND_MODE_FIRST, + PM_SUSPEND_MODE_POWER_OFF, +}; + +#define PM_SUSPEND_MODE_FIRST PM_SUSPEND_MODE_STD + +static const char *const suspend_modes[] = { + [PM_SUSPEND_MODE_STD] = "standard", + [PM_SUSPEND_MODE_POWER_OFF] = "power-off", +}; + +static enum pm_suspend_mode suspend_mode = PM_SUSPEND_MODE_STD; + +enum pm_api_cb_id { + PM_INIT_SUSPEND_CB = 30, + PM_ACKNOWLEDGE_CB, + PM_NOTIFY_CB, +}; + +static void zynqmp_pm_get_callback_data(u32 *buf) +{ + zynqmp_pm_invoke_fn(GET_CALLBACK_DATA, 0, 0, 0, 0, buf); +} + +static irqreturn_t zynqmp_pm_isr(int irq, void *data) +{ + u32 payload[CB_PAYLOAD_SIZE]; + + zynqmp_pm_get_callback_data(payload); + + /* First element is callback API ID, others are callback arguments */ + if (payload[0] == PM_INIT_SUSPEND_CB) { + switch (payload[1]) { + case SUSPEND_SYSTEM_SHUTDOWN: + orderly_poweroff(true); + break; + case SUSPEND_POWER_REQUEST: + pm_suspend(PM_SUSPEND_MEM); + break; + default: + pr_err("%s Unsupported InitSuspendCb reason " + "code %d\n", __func__, payload[1]); + } + } + + return IRQ_HANDLED; +} + +static void ipi_receive_callback(struct mbox_client *cl, void *data) +{ + struct zynqmp_ipi_message *msg = (struct zynqmp_ipi_message *)data; + u32 payload[CB_PAYLOAD_SIZE]; + int ret; + + memcpy(payload, msg->data, sizeof(msg->len)); + /* First element is callback API ID, others are callback arguments */ + if (payload[0] == PM_INIT_SUSPEND_CB) { + if (work_pending(&zynqmp_pm_init_suspend_work->callback_work)) + return; + + /* Copy callback arguments into work's structure */ + memcpy(zynqmp_pm_init_suspend_work->args, &payload[1], + sizeof(zynqmp_pm_init_suspend_work->args)); + + queue_work(system_unbound_wq, + &zynqmp_pm_init_suspend_work->callback_work); + + /* Send NULL message to mbox controller to ack the message */ + ret = mbox_send_message(rx_chan, NULL); + if (ret) + pr_err("IPI ack failed. Error %d\n", ret); + } +} + +/** + * zynqmp_pm_init_suspend_work_fn - Initialize suspend + * @work: Pointer to work_struct + * + * Bottom-half of PM callback IRQ handler. + */ +static void zynqmp_pm_init_suspend_work_fn(struct work_struct *work) +{ + struct zynqmp_pm_work_struct *pm_work = + container_of(work, struct zynqmp_pm_work_struct, callback_work); + + if (pm_work->args[0] == SUSPEND_SYSTEM_SHUTDOWN) { + orderly_poweroff(true); + } else if (pm_work->args[0] == SUSPEND_POWER_REQUEST) { + pm_suspend(PM_SUSPEND_MEM); + } else { + pr_err("%s Unsupported InitSuspendCb reason code %d.\n", + __func__, pm_work->args[0]); + } +} + +static ssize_t suspend_mode_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + char *s = buf; + int md; + + for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++) + if (suspend_modes[md]) { + if (md == suspend_mode) + s += sprintf(s, "[%s] ", suspend_modes[md]); + else + s += sprintf(s, "%s ", suspend_modes[md]); + } + + /* Convert last space to newline */ + if (s != buf) + *(s - 1) = '\n'; + return (s - buf); +} + +static ssize_t suspend_mode_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int md, ret = -EINVAL; + + for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++) + if (suspend_modes[md] && + sysfs_streq(suspend_modes[md], buf)) { + ret = 0; + break; + } + + if (!ret && md != suspend_mode) { + ret = zynqmp_pm_set_suspend_mode(md); + if (likely(!ret)) + suspend_mode = md; + } + + return ret ? ret : count; +} + +static DEVICE_ATTR_RW(suspend_mode); + +static int zynqmp_pm_probe(struct platform_device *pdev) +{ + int ret, irq; + u32 pm_api_version; + struct mbox_client *client; + + zynqmp_pm_init_finalize(); + zynqmp_pm_get_api_version(&pm_api_version); + + /* Check PM API version number */ + if (pm_api_version < ZYNQMP_PM_VERSION) + return -ENODEV; + + if (of_find_property(pdev->dev.of_node, "mboxes", NULL)) { + zynqmp_pm_init_suspend_work = + devm_kzalloc(&pdev->dev, + sizeof(struct zynqmp_pm_work_struct), + GFP_KERNEL); + if (!zynqmp_pm_init_suspend_work) + return -ENOMEM; + + INIT_WORK(&zynqmp_pm_init_suspend_work->callback_work, + zynqmp_pm_init_suspend_work_fn); + client = devm_kzalloc(&pdev->dev, sizeof(*client), GFP_KERNEL); + if (!client) + return -ENOMEM; + + client->dev = &pdev->dev; + client->rx_callback = ipi_receive_callback; + + rx_chan = mbox_request_channel_byname(client, "rx"); + if (IS_ERR(rx_chan)) { + dev_err(&pdev->dev, "Failed to request rx channel\n"); + return PTR_ERR(rx_chan); + } + } else if (of_find_property(pdev->dev.of_node, "interrupts", NULL)) { + irq = platform_get_irq(pdev, 0); + if (irq <= 0) + return -ENXIO; + + ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, + zynqmp_pm_isr, + IRQF_NO_SUSPEND | IRQF_ONESHOT, + dev_name(&pdev->dev), + &pdev->dev); + if (ret) { + dev_err(&pdev->dev, "devm_request_threaded_irq '%d' " + "failed with %d\n", irq, ret); + return ret; + } + } else { + dev_err(&pdev->dev, "Required property not found in DT node\n"); + return -ENOENT; + } + + ret = sysfs_create_file(&pdev->dev.kobj, &dev_attr_suspend_mode.attr); + if (ret) { + dev_err(&pdev->dev, "unable to create sysfs interface\n"); + return ret; + } + + return 0; +} + +static int zynqmp_pm_remove(struct platform_device *pdev) +{ + sysfs_remove_file(&pdev->dev.kobj, &dev_attr_suspend_mode.attr); + + if (!rx_chan) + mbox_free_channel(rx_chan); + + return 0; +} + +static const struct of_device_id pm_of_match[] = { + { .compatible = "xlnx,zynqmp-power", }, + { /* end of table */ }, +}; +MODULE_DEVICE_TABLE(of, pm_of_match); + +static struct platform_driver zynqmp_pm_platform_driver = { + .probe = zynqmp_pm_probe, + .remove = zynqmp_pm_remove, + .driver = { + .name = "zynqmp_power", + .of_match_table = pm_of_match, + }, +}; +module_platform_driver(zynqmp_pm_platform_driver); |