Hi Bjorn, Thanks for the review On 6/14/21 4:53 PM, Bjorn Andersson wrote:
On Tue 08 Jun 17:29 CDT 2021, 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 + input from temperature and current sensors. On many newer Qualcomm SoCs + LMH is configure in the firmware and this feature need not be enabled. + However, on certain SoCs like sdm845 LMH has to be configured from HLOS. diff --git a/drivers/thermal/qcom/Makefile b/drivers/thermal/qcom/Makefile index 252ea7d9da0b..0fa2512042e7 100644 --- a/drivers/thermal/qcom/Makefile +++ b/drivers/thermal/qcom/Makefile @@ -5,3 +5,4 @@ qcom_tsens-y += tsens.o tsens-v2.o tsens-v1.o tsens-v0_1.o \ tsens-8960.o obj-$(CONFIG_QCOM_SPMI_ADC_TM5) += qcom-spmi-adc-tm5.o obj-$(CONFIG_QCOM_SPMI_TEMP_ALARM) += qcom-spmi-temp-alarm.o +obj-$(CONFIG_QCOM_LMH) += lmh.o 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. + */ +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/irqdomain.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/of_platform.h> +#include <linux/slab.h> +#include <linux/qcom_scm.h> + +#define LMH_NODE_DCVS 0x44435653 +#define LMH_CLUSTER0_NODE_ID 0x6370302D +#define LMH_CLUSTER1_NODE_ID 0x6370312D + +#define LMH_SUB_FN_THERMAL 0x54484D4C +#define LMH_SUB_FN_CRNT 0x43524E54 +#define LMH_SUB_FN_REL 0x52454C00 +#define LMH_SUB_FN_BCL 0x42434C00 + +#define LMH_ALGO_MODE_ENABLE 0x454E424C +#define LMH_TH_HI_THRESHOLD 0x48494748 +#define LMH_TH_LOW_THRESHOLD 0x4C4F5700 +#define LMH_TH_ARM_THRESHOLD 0x41524D00 + +#define LMH_TH_HI_TEMP 95000 +#define LMH_TH_LOW_TEMP 94500 +#define LMH_TH_ARM_TEMP 65000 + +#define LMH_REG_DCVS_INTR_CLR 0x8 + +struct lmh_hw_data { + void __iomem *base; + struct irq_domain *domain; + int irq; + u32 payload[5]; + u32 payload_size; + u32 cpu_id; +}; + +static void update_payload(struct lmh_hw_data *lmh_data, u32 fn, u32 reg, u32 val)Please pass fn, reg and val in the scm function call instead and stuff the payload array in the scm driver instead.
Sure . I will redo this part.
+{ + lmh_data->payload[0] = fn; + lmh_data->payload[1] = 0; + lmh_data->payload[2] = reg; + lmh_data->payload[3] = 1; + lmh_data->payload[4] = val; +} + +static irqreturn_t lmh_handle_irq(int hw_irq, void *data) +{ + struct lmh_hw_data *lmh_data = data; + int irq = irq_find_mapping(lmh_data->domain, 0); + + /* + * Disable interrupt and call the cpufreq driver to handle the interrupt + * cpufreq will enable the interrupt once finished processing. + */ + disable_irq_nosync(lmh_data->irq);The contract between this driver's disabling of the IRQ and the cpufreq-hw driver's enabling it when we're done polling does worry me. In the case of EPSS, don't we disable the interrupt during the polling there as well? If that's the case wouldn't it be better to implement irq_chip->irq_disable and have the cpufreq-hw driver do the disable in both cases?
Yes. You are right. In case of EPSS, the cpufreq-hw will have to disable the interrupt. I did think of the approach you suggested here. My only issue is that we will dispatch the interrupt to cpufreq-hw without it disabling it and hence the interrupt could fire again, right ?
+ if (irq) + generic_handle_irq(irq); + + return 0; +} + +static void lmh_enable_interrupt(struct irq_data *d) +{ + struct lmh_hw_data *lmh_data = irq_data_get_irq_chip_data(d); + + /* Clear the existing interrupt */ + writel_relaxed(0xFF, lmh_data->base + LMH_REG_DCVS_INTR_CLR);Please avoid using _relaxed versions of writel, unless there's a strong reason and please lowercase the hex digits.
Sure.
+ enable_irq(lmh_data->irq); +} + +static struct irq_chip lmh_irq_chip = { + .name = "lmh", + .irq_enable = lmh_enable_interrupt, +}; + +static int lmh_irq_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw) +{ + struct lmh_hw_data *lmh_data = d->host_data; + + irq_set_chip_and_handler(irq, &lmh_irq_chip, handle_simple_irq); + irq_set_chip_data(irq, lmh_data); + + return 0; +} + +static const struct irq_domain_ops lmh_irq_ops = { + .map = lmh_irq_map, + .xlate = irq_domain_xlate_onecell, +}; + +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"); + 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); + 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); + 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); + 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); + 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", },Don't we need platform specific compatibles? Perhaps "qcom,<platform>-lmh"?
Yes considering that is the norm, I will follow it.
If we're going with a generic compatible I think that should be done in addition to a platform-specific one (and qcom,lmh should be sufficien >+ {},Please omit the comma here.
Ok.
+};Driver is tristate, so you need a MODULE_DEVICE_TABLE(of, lmh_table); here, to make sure the module is loaded automatically based on the compatible strings in DT.
Right. I will fix it .
Regards, Bjorn+ +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"); -- 2.25.1
-- Warm Regards Thara (She/Her/Hers)
