On 6/8/21 3:29 PM, Thara Gopinath wrote:
> Driver enabling various pieces of Limits Management Hardware(LMh) for cpu
> cluster0 and cpu cluster1 namely kick starting monitoring of temperature,
> current, battery current violations, enabling reliability algorithm and
> setting up various temperature limits.
>
> The following has been explained in the cover letter. I am including this
> here so that this remains in the commit message as well.
>
> LMh is a hardware infrastructure on some Qualcomm SoCs that can enforce
> temperature and current limits as programmed by software for certain IPs
> like CPU. On many newer SoCs LMh is configured by firmware/TZ and no
> programming is needed from the kernel side. But on certain SoCs like sdm845
> the firmware does not do a complete programming of the h/w. On such SoCs
> kernel software has to explicitly set up the temperature limits and turn on
> various monitoring and enforcing algorithms on the hardware.
>
> Signed-off-by: Thara Gopinath <thara.gopinath@xxxxxxxxxx>
> ---
> drivers/thermal/qcom/Kconfig | 10 ++
> drivers/thermal/qcom/Makefile | 1 +
> drivers/thermal/qcom/lmh.c | 244 ++++++++++++++++++++++++++++++++++
> 3 files changed, 255 insertions(+)
> create mode 100644 drivers/thermal/qcom/lmh.c
>
> diff --git a/drivers/thermal/qcom/Kconfig b/drivers/thermal/qcom/Kconfig
> index 8d5ac2df26dc..c95b95e254d7 100644
> --- a/drivers/thermal/qcom/Kconfig
> +++ b/drivers/thermal/qcom/Kconfig
> @@ -31,3 +31,13 @@ config QCOM_SPMI_TEMP_ALARM
> trip points. The temperature reported by the thermal sensor reflects the
> real time die temperature if an ADC is present or an estimate of the
> temperature based upon the over temperature stage value.
> +
> +config QCOM_LMH
> + tristate "Qualcomm Limits Management Hardware"
> + depends on ARCH_QCOM
> + help
> + This enables initialization of Qualcomm limits management
> + hardware(LMh). LMh allows for h/w enforced mitigation for cpus based on
hardware-enforced CPUs
> + input from temperature and current sensors. On many newer Qualcomm SoCs
> + LMH is configure in the firmware and this feature need not be enabled.
LMh
> + However, on certain SoCs like sdm845 LMH has to be configured from HLOS.
LMh
What is HLOS?
> diff --git a/drivers/thermal/qcom/lmh.c b/drivers/thermal/qcom/lmh.c
> new file mode 100644
> index 000000000000..8741a36cb674
> --- /dev/null
> +++ b/drivers/thermal/qcom/lmh.c
> @@ -0,0 +1,244 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +
> +/*
> + * Copyright (C) 2021, Linaro Limited. All rights reserved.
> + */
[snip]
> +static int lmh_probe(struct platform_device *pdev)
> +{
> + struct device *dev;
> + struct device_node *np;
> + struct lmh_hw_data *lmh_data;
> + u32 node_id;
> + int ret;
> +
> + dev = &pdev->dev;
> + np = dev->of_node;
> + if (!np)
> + return -EINVAL;
> +
> + lmh_data = devm_kzalloc(dev, sizeof(*lmh_data), GFP_KERNEL);
> + if (!lmh_data)
> + return -ENOMEM;
> +
> + lmh_data->base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(lmh_data->base))
> + return PTR_ERR(lmh_data->base);
> +
> + ret = of_property_read_u32(np, "qcom,lmh-cpu-id", &lmh_data->cpu_id);
> + if (ret)
> + return -ENODEV;
> +
> + /*
> + * Only sdm845 has lmh hardware currently enabled from hlos. If this is needed
> + * for other platforms, revisit this to check if the <cpu-id, node-id> should be part
> + * of a dt match table.
> + */
> + if (lmh_data->cpu_id == 0) {
> + node_id = LMH_CLUSTER0_NODE_ID;
> + } else if (lmh_data->cpu_id == 4) {
> + node_id = LMH_CLUSTER1_NODE_ID;
> + } else {
> + dev_err(dev, "Wrong cpu id associated with lmh node\n");
CPU LMh
> + return -EINVAL;
> + }
> +
> + /* Payload size is five bytes for now */
> + lmh_data->payload_size = 5 * sizeof(u32);
> +
> + platform_set_drvdata(pdev, lmh_data);
> +
> + if (!qcom_scm_lmh_dcvsh_available())
> + return -EINVAL;
> +
> + /* Enable Thermal Algorithm */
> + update_payload(lmh_data, LMH_SUB_FN_THERMAL, LMH_ALGO_MODE_ENABLE, 1);
> + ret = qcom_scm_lmh_dcvsh(lmh_data->payload, lmh_data->payload_size,
> + LMH_NODE_DCVS, node_id, 0);
> + if (ret) {
> + dev_err(dev, "Error %d enabling thermal subfunction\n", ret);
> + return ret;
> + }
> +
> + /* Enable Current Sensing Algorithm */
> + update_payload(lmh_data, LMH_SUB_FN_CRNT, LMH_ALGO_MODE_ENABLE, 1);
> + ret = qcom_scm_lmh_dcvsh(lmh_data->payload, lmh_data->payload_size,
> + LMH_NODE_DCVS, node_id, 0);
> + if (ret) {
> + dev_err(dev, "Error %d enabling current subfunction\n", ret);
> + return ret;
> + }
> +
> + /* Enable Reliability Algorithm */
> + update_payload(lmh_data, LMH_SUB_FN_REL, LMH_ALGO_MODE_ENABLE, 1);
> + ret = qcom_scm_lmh_dcvsh(lmh_data->payload, lmh_data->payload_size,
> + LMH_NODE_DCVS, node_id, 0);
> + if (ret) {
> + dev_err(dev, "Error %d enabling reliability subfunction\n", ret);
> + return ret;
> + }
> +
> + /* Enable BCL Algorithm */
> + update_payload(lmh_data, LMH_SUB_FN_BCL, LMH_ALGO_MODE_ENABLE, 1);
> + ret = qcom_scm_lmh_dcvsh(lmh_data->payload, lmh_data->payload_size,
> + LMH_NODE_DCVS, node_id, 0);
> + if (ret) {
> + dev_err(dev, "Error %d enabling BCL subfunction\n", ret);
What is BCL?
> + return ret;
> + }
> +
> + ret = qcom_scm_lmh_profile_change(0x1);
> + if (ret) {
> + dev_err(dev, "Error %d changing profile\n", ret);
> + return ret;
> + }
> +
> + /* Set default thermal trips */
> + update_payload(lmh_data, LMH_SUB_FN_THERMAL, LMH_TH_ARM_THRESHOLD, LMH_TH_ARM_TEMP);
> + ret = qcom_scm_lmh_dcvsh(lmh_data->payload, lmh_data->payload_size,
> + LMH_NODE_DCVS, node_id, 0);
> + if (ret) {
> + dev_err(dev, "Error setting thermal ARM thershold%d\n", ret);
threshold
> + return ret;
> + }
> +
> + update_payload(lmh_data, LMH_SUB_FN_THERMAL, LMH_TH_HI_THRESHOLD, LMH_TH_HI_TEMP);
> + ret = qcom_scm_lmh_dcvsh(lmh_data->payload, lmh_data->payload_size,
> + LMH_NODE_DCVS, node_id, 0);
> + if (ret) {
> + dev_err(dev, "Error setting thermal HI thershold%d\n", ret);
threshold
> + return ret;
> + }
> + update_payload(lmh_data, LMH_SUB_FN_THERMAL, LMH_TH_LOW_THRESHOLD, LMH_TH_LOW_TEMP);
> + ret = qcom_scm_lmh_dcvsh(lmh_data->payload, lmh_data->payload_size,
> + LMH_NODE_DCVS, node_id, 0);
> + if (ret) {
> + dev_err(dev, "Error setting thermal ARM thershold%d\n", ret);
threshold
> + return ret;
> + }
> +
> + lmh_data->irq = platform_get_irq(pdev, 0);
> + lmh_data->domain = irq_domain_add_linear(np, 1, &lmh_irq_ops, lmh_data);
> + if (!lmh_data->domain) {
> + dev_err(dev, "Error adding irq_domain\n");
> + return -EINVAL;
> + }
> +
> + ret = devm_request_irq(dev, lmh_data->irq, lmh_handle_irq,
> + IRQF_TRIGGER_HIGH | IRQF_ONESHOT | IRQF_NO_SUSPEND,
> + "lmh-irq", lmh_data);
> + if (ret) {
> + dev_err(dev, "Error %d registering irq %x\n", ret, lmh_data->irq);
> + irq_domain_remove(lmh_data->domain);
> + return ret;
> + }
> + return 0;
> +}
> +
> +static const struct of_device_id lmh_table[] = {
> + { .compatible = "qcom,msm-hw-limits", },
> + {},
> +};
> +
> +static struct platform_driver lmh_driver = {
> + .probe = lmh_probe,
> + .driver = {
> + .name = "qcom-lmh",
> + .of_match_table = lmh_table,
> + },
> +};
> +module_platform_driver(lmh_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_DESCRIPTION("QCOM LMH driver");
LMh
thanks.
--
~Randy
