thermal: tegra: add support for EDP IRQ
authorWei Ni <wni@nvidia.com>
Thu, 21 Feb 2019 10:18:44 +0000 (18:18 +0800)
committerEduardo Valentin <edubezval@gmail.com>
Tue, 14 May 2019 03:35:34 +0000 (20:35 -0700)
Add support to generate OC (over-current) interrupts to
indicate the OC event and print out alarm messages.

Signed-off-by: Wei Ni <wni@nvidia.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
drivers/thermal/tegra/soctherm.c

index 9e66ea7..35a9f1e 100644 (file)
@@ -23,6 +23,8 @@
 #include <linux/err.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #define STATS_CTL_CLR_UP                       0x2
 #define STATS_CTL_EN_UP                                0x1
 
+#define OC_INTR_STATUS                         0x39c
+#define OC_INTR_ENABLE                         0x3a0
+#define OC_INTR_DISABLE                                0x3a4
+
+#define OC_INTR_OC1_MASK                       BIT(0)
+#define OC_INTR_OC2_MASK                       BIT(1)
+#define OC_INTR_OC3_MASK                       BIT(2)
+#define OC_INTR_OC4_MASK                       BIT(3)
+#define OC_INTR_OC5_MASK                       BIT(4)
+
 #define THROT_GLOBAL_CFG                       0x400
 #define THROT_GLOBAL_ENB_MASK                  BIT(0)
 
@@ -212,9 +224,23 @@ static const int max_high_temp = 127000;
 enum soctherm_throttle_id {
        THROTTLE_LIGHT = 0,
        THROTTLE_HEAVY,
+       THROTTLE_OC1,
+       THROTTLE_OC2,
+       THROTTLE_OC3,
+       THROTTLE_OC4,
+       THROTTLE_OC5, /* OC5 is reserved */
        THROTTLE_SIZE,
 };
 
+enum soctherm_oc_irq_id {
+       TEGRA_SOC_OC_IRQ_1,
+       TEGRA_SOC_OC_IRQ_2,
+       TEGRA_SOC_OC_IRQ_3,
+       TEGRA_SOC_OC_IRQ_4,
+       TEGRA_SOC_OC_IRQ_5,
+       TEGRA_SOC_OC_IRQ_MAX,
+};
+
 enum soctherm_throttle_dev_id {
        THROTTLE_DEV_CPU = 0,
        THROTTLE_DEV_GPU,
@@ -224,6 +250,11 @@ enum soctherm_throttle_dev_id {
 static const char *const throt_names[] = {
        [THROTTLE_LIGHT] = "light",
        [THROTTLE_HEAVY] = "heavy",
+       [THROTTLE_OC1]   = "oc1",
+       [THROTTLE_OC2]   = "oc2",
+       [THROTTLE_OC3]   = "oc3",
+       [THROTTLE_OC4]   = "oc4",
+       [THROTTLE_OC5]   = "oc5",
 };
 
 struct tegra_soctherm;
@@ -255,6 +286,7 @@ struct tegra_soctherm {
        void __iomem *ccroc_regs;
 
        int thermal_irq;
+       int edp_irq;
 
        u32 *calib;
        struct thermal_zone_device **thermctl_tzs;
@@ -267,6 +299,15 @@ struct tegra_soctherm {
        struct mutex thermctl_lock;
 };
 
+struct soctherm_oc_irq_chip_data {
+       struct mutex            irq_lock; /* serialize OC IRQs */
+       struct irq_chip         irq_chip;
+       struct irq_domain       *domain;
+       int                     irq_enable;
+};
+
+static struct soctherm_oc_irq_chip_data soc_irq_cdata;
+
 /**
  * ccroc_writel() - writes a value to a CCROC register
  * @ts: pointer to a struct tegra_soctherm
@@ -839,6 +880,360 @@ static irqreturn_t soctherm_thermal_isr_thread(int irq, void *dev_id)
        return IRQ_HANDLED;
 }
 
+/**
+ * soctherm_oc_intr_enable() - Enables the soctherm over-current interrupt
+ * @alarm:             The soctherm throttle id
+ * @enable:            Flag indicating enable the soctherm over-current
+ *                     interrupt or disable it
+ *
+ * Enables a specific over-current pins @alarm to raise an interrupt if the flag
+ * is set and the alarm corresponds to OC1, OC2, OC3, or OC4.
+ */
+static void soctherm_oc_intr_enable(struct tegra_soctherm *ts,
+                                   enum soctherm_throttle_id alarm,
+                                   bool enable)
+{
+       u32 r;
+
+       if (!enable)
+               return;
+
+       r = readl(ts->regs + OC_INTR_ENABLE);
+       switch (alarm) {
+       case THROTTLE_OC1:
+               r = REG_SET_MASK(r, OC_INTR_OC1_MASK, 1);
+               break;
+       case THROTTLE_OC2:
+               r = REG_SET_MASK(r, OC_INTR_OC2_MASK, 1);
+               break;
+       case THROTTLE_OC3:
+               r = REG_SET_MASK(r, OC_INTR_OC3_MASK, 1);
+               break;
+       case THROTTLE_OC4:
+               r = REG_SET_MASK(r, OC_INTR_OC4_MASK, 1);
+               break;
+       default:
+               r = 0;
+               break;
+       }
+       writel(r, ts->regs + OC_INTR_ENABLE);
+}
+
+/**
+ * soctherm_handle_alarm() - Handles soctherm alarms
+ * @alarm:             The soctherm throttle id
+ *
+ * "Handles" over-current alarms (OC1, OC2, OC3, and OC4) by printing
+ * a warning or informative message.
+ *
+ * Return: -EINVAL for @alarm = THROTTLE_OC3, otherwise 0 (success).
+ */
+static int soctherm_handle_alarm(enum soctherm_throttle_id alarm)
+{
+       int rv = -EINVAL;
+
+       switch (alarm) {
+       case THROTTLE_OC1:
+               pr_debug("soctherm: Successfully handled OC1 alarm\n");
+               rv = 0;
+               break;
+
+       case THROTTLE_OC2:
+               pr_debug("soctherm: Successfully handled OC2 alarm\n");
+               rv = 0;
+               break;
+
+       case THROTTLE_OC3:
+               pr_debug("soctherm: Successfully handled OC3 alarm\n");
+               rv = 0;
+               break;
+
+       case THROTTLE_OC4:
+               pr_debug("soctherm: Successfully handled OC4 alarm\n");
+               rv = 0;
+               break;
+
+       default:
+               break;
+       }
+
+       if (rv)
+               pr_err("soctherm: ERROR in handling %s alarm\n",
+                      throt_names[alarm]);
+
+       return rv;
+}
+
+/**
+ * soctherm_edp_isr_thread() - log an over-current interrupt request
+ * @irq:       OC irq number. Currently not being used. See description
+ * @arg:       a void pointer for callback, currently not being used
+ *
+ * Over-current events are handled in hardware. This function is called to log
+ * and handle any OC events that happened. Additionally, it checks every
+ * over-current interrupt registers for registers are set but
+ * was not expected (i.e. any discrepancy in interrupt status) by the function,
+ * the discrepancy will logged.
+ *
+ * Return: %IRQ_HANDLED
+ */
+static irqreturn_t soctherm_edp_isr_thread(int irq, void *arg)
+{
+       struct tegra_soctherm *ts = arg;
+       u32 st, ex, oc1, oc2, oc3, oc4;
+
+       st = readl(ts->regs + OC_INTR_STATUS);
+
+       /* deliberately clear expected interrupts handled in SW */
+       oc1 = st & OC_INTR_OC1_MASK;
+       oc2 = st & OC_INTR_OC2_MASK;
+       oc3 = st & OC_INTR_OC3_MASK;
+       oc4 = st & OC_INTR_OC4_MASK;
+       ex = oc1 | oc2 | oc3 | oc4;
+
+       pr_err("soctherm: OC ALARM 0x%08x\n", ex);
+       if (ex) {
+               writel(st, ts->regs + OC_INTR_STATUS);
+               st &= ~ex;
+
+               if (oc1 && !soctherm_handle_alarm(THROTTLE_OC1))
+                       soctherm_oc_intr_enable(ts, THROTTLE_OC1, true);
+
+               if (oc2 && !soctherm_handle_alarm(THROTTLE_OC2))
+                       soctherm_oc_intr_enable(ts, THROTTLE_OC2, true);
+
+               if (oc3 && !soctherm_handle_alarm(THROTTLE_OC3))
+                       soctherm_oc_intr_enable(ts, THROTTLE_OC3, true);
+
+               if (oc4 && !soctherm_handle_alarm(THROTTLE_OC4))
+                       soctherm_oc_intr_enable(ts, THROTTLE_OC4, true);
+
+               if (oc1 && soc_irq_cdata.irq_enable & BIT(0))
+                       handle_nested_irq(
+                               irq_find_mapping(soc_irq_cdata.domain, 0));
+
+               if (oc2 && soc_irq_cdata.irq_enable & BIT(1))
+                       handle_nested_irq(
+                               irq_find_mapping(soc_irq_cdata.domain, 1));
+
+               if (oc3 && soc_irq_cdata.irq_enable & BIT(2))
+                       handle_nested_irq(
+                               irq_find_mapping(soc_irq_cdata.domain, 2));
+
+               if (oc4 && soc_irq_cdata.irq_enable & BIT(3))
+                       handle_nested_irq(
+                               irq_find_mapping(soc_irq_cdata.domain, 3));
+       }
+
+       if (st) {
+               pr_err("soctherm: Ignored unexpected OC ALARM 0x%08x\n", st);
+               writel(st, ts->regs + OC_INTR_STATUS);
+       }
+
+       return IRQ_HANDLED;
+}
+
+/**
+ * soctherm_edp_isr() - Disables any active interrupts
+ * @irq:       The interrupt request number
+ * @arg:       Opaque pointer to an argument
+ *
+ * Writes to the OC_INTR_DISABLE register the over current interrupt status,
+ * masking any asserted interrupts. Doing this prevents the same interrupts
+ * from triggering this isr repeatedly. The thread woken by this isr will
+ * handle asserted interrupts and subsequently unmask/re-enable them.
+ *
+ * The OC_INTR_DISABLE register indicates which OC interrupts
+ * have been disabled.
+ *
+ * Return: %IRQ_WAKE_THREAD, handler requests to wake the handler thread
+ */
+static irqreturn_t soctherm_edp_isr(int irq, void *arg)
+{
+       struct tegra_soctherm *ts = arg;
+       u32 r;
+
+       if (!ts)
+               return IRQ_NONE;
+
+       r = readl(ts->regs + OC_INTR_STATUS);
+       writel(r, ts->regs + OC_INTR_DISABLE);
+
+       return IRQ_WAKE_THREAD;
+}
+
+/**
+ * soctherm_oc_irq_lock() - locks the over-current interrupt request
+ * @data:      Interrupt request data
+ *
+ * Looks up the chip data from @data and locks the mutex associated with
+ * a particular over-current interrupt request.
+ */
+static void soctherm_oc_irq_lock(struct irq_data *data)
+{
+       struct soctherm_oc_irq_chip_data *d = irq_data_get_irq_chip_data(data);
+
+       mutex_lock(&d->irq_lock);
+}
+
+/**
+ * soctherm_oc_irq_sync_unlock() - Unlocks the OC interrupt request
+ * @data:              Interrupt request data
+ *
+ * Looks up the interrupt request data @data and unlocks the mutex associated
+ * with a particular over-current interrupt request.
+ */
+static void soctherm_oc_irq_sync_unlock(struct irq_data *data)
+{
+       struct soctherm_oc_irq_chip_data *d = irq_data_get_irq_chip_data(data);
+
+       mutex_unlock(&d->irq_lock);
+}
+
+/**
+ * soctherm_oc_irq_enable() - Enables the SOC_THERM over-current interrupt queue
+ * @data:       irq_data structure of the chip
+ *
+ * Sets the irq_enable bit of SOC_THERM allowing SOC_THERM
+ * to respond to over-current interrupts.
+ *
+ */
+static void soctherm_oc_irq_enable(struct irq_data *data)
+{
+       struct soctherm_oc_irq_chip_data *d = irq_data_get_irq_chip_data(data);
+
+       d->irq_enable |= BIT(data->hwirq);
+}
+
+/**
+ * soctherm_oc_irq_disable() - Disables overcurrent interrupt requests
+ * @irq_data:  The interrupt request information
+ *
+ * Clears the interrupt request enable bit of the overcurrent
+ * interrupt request chip data.
+ *
+ * Return: Nothing is returned (void)
+ */
+static void soctherm_oc_irq_disable(struct irq_data *data)
+{
+       struct soctherm_oc_irq_chip_data *d = irq_data_get_irq_chip_data(data);
+
+       d->irq_enable &= ~BIT(data->hwirq);
+}
+
+static int soctherm_oc_irq_set_type(struct irq_data *data, unsigned int type)
+{
+       return 0;
+}
+
+/**
+ * soctherm_oc_irq_map() - SOC_THERM interrupt request domain mapper
+ * @h:         Interrupt request domain
+ * @virq:      Virtual interrupt request number
+ * @hw:                Hardware interrupt request number
+ *
+ * Mapping callback function for SOC_THERM's irq_domain. When a SOC_THERM
+ * interrupt request is called, the irq_domain takes the request's virtual
+ * request number (much like a virtual memory address) and maps it to a
+ * physical hardware request number.
+ *
+ * When a mapping doesn't already exist for a virtual request number, the
+ * irq_domain calls this function to associate the virtual request number with
+ * a hardware request number.
+ *
+ * Return: 0
+ */
+static int soctherm_oc_irq_map(struct irq_domain *h, unsigned int virq,
+               irq_hw_number_t hw)
+{
+       struct soctherm_oc_irq_chip_data *data = h->host_data;
+
+       irq_set_chip_data(virq, data);
+       irq_set_chip(virq, &data->irq_chip);
+       irq_set_nested_thread(virq, 1);
+       return 0;
+}
+
+/**
+ * soctherm_irq_domain_xlate_twocell() - xlate for soctherm interrupts
+ * @d:      Interrupt request domain
+ * @intspec:    Array of u32s from DTs "interrupt" property
+ * @intsize:    Number of values inside the intspec array
+ * @out_hwirq:  HW IRQ value associated with this interrupt
+ * @out_type:   The IRQ SENSE type for this interrupt.
+ *
+ * This Device Tree IRQ specifier translation function will translate a
+ * specific "interrupt" as defined by 2 DT values where the cell values map
+ * the hwirq number + 1 and linux irq flags. Since the output is the hwirq
+ * number, this function will subtract 1 from the value listed in DT.
+ *
+ * Return: 0
+ */
+static int soctherm_irq_domain_xlate_twocell(struct irq_domain *d,
+       struct device_node *ctrlr, const u32 *intspec, unsigned int intsize,
+       irq_hw_number_t *out_hwirq, unsigned int *out_type)
+{
+       if (WARN_ON(intsize < 2))
+               return -EINVAL;
+
+       /*
+        * The HW value is 1 index less than the DT IRQ values.
+        * i.e. OC4 goes to HW index 3.
+        */
+       *out_hwirq = intspec[0] - 1;
+       *out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
+       return 0;
+}
+
+static const struct irq_domain_ops soctherm_oc_domain_ops = {
+       .map    = soctherm_oc_irq_map,
+       .xlate  = soctherm_irq_domain_xlate_twocell,
+};
+
+/**
+ * soctherm_oc_int_init() - Initial enabling of the over
+ * current interrupts
+ * @np:        The devicetree node for soctherm
+ * @num_irqs:  The number of new interrupt requests
+ *
+ * Sets the over current interrupt request chip data
+ *
+ * Return: 0 on success or if overcurrent interrupts are not enabled,
+ * -ENOMEM (out of memory), or irq_base if the function failed to
+ * allocate the irqs
+ */
+static int soctherm_oc_int_init(struct device_node *np, int num_irqs)
+{
+       if (!num_irqs) {
+               pr_info("%s(): OC interrupts are not enabled\n", __func__);
+               return 0;
+       }
+
+       mutex_init(&soc_irq_cdata.irq_lock);
+       soc_irq_cdata.irq_enable = 0;
+
+       soc_irq_cdata.irq_chip.name = "soc_therm_oc";
+       soc_irq_cdata.irq_chip.irq_bus_lock = soctherm_oc_irq_lock;
+       soc_irq_cdata.irq_chip.irq_bus_sync_unlock =
+               soctherm_oc_irq_sync_unlock;
+       soc_irq_cdata.irq_chip.irq_disable = soctherm_oc_irq_disable;
+       soc_irq_cdata.irq_chip.irq_enable = soctherm_oc_irq_enable;
+       soc_irq_cdata.irq_chip.irq_set_type = soctherm_oc_irq_set_type;
+       soc_irq_cdata.irq_chip.irq_set_wake = NULL;
+
+       soc_irq_cdata.domain = irq_domain_add_linear(np, num_irqs,
+                                                    &soctherm_oc_domain_ops,
+                                                    &soc_irq_cdata);
+
+       if (!soc_irq_cdata.domain) {
+               pr_err("%s: Failed to create IRQ domain\n", __func__);
+               return -ENOMEM;
+       }
+
+       pr_debug("%s(): OC interrupts enabled successful\n", __func__);
+       return 0;
+}
+
 #ifdef CONFIG_DEBUG_FS
 static int regs_show(struct seq_file *s, void *data)
 {
@@ -1504,14 +1899,27 @@ static void tegra_soctherm_throttle(struct device *dev)
 static int soctherm_interrupts_init(struct platform_device *pdev,
                                    struct tegra_soctherm *tegra)
 {
+       struct device_node *np = pdev->dev.of_node;
        int ret;
 
+       ret = soctherm_oc_int_init(np, TEGRA_SOC_OC_IRQ_MAX);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "soctherm_oc_int_init failed\n");
+               return ret;
+       }
+
        tegra->thermal_irq = platform_get_irq(pdev, 0);
        if (tegra->thermal_irq < 0) {
                dev_dbg(&pdev->dev, "get 'thermal_irq' failed.\n");
                return 0;
        }
 
+       tegra->edp_irq = platform_get_irq(pdev, 1);
+       if (tegra->edp_irq < 0) {
+               dev_dbg(&pdev->dev, "get 'edp_irq' failed.\n");
+               return 0;
+       }
+
        ret = devm_request_threaded_irq(&pdev->dev,
                                        tegra->thermal_irq,
                                        soctherm_thermal_isr,
@@ -1524,6 +1932,18 @@ static int soctherm_interrupts_init(struct platform_device *pdev,
                return ret;
        }
 
+       ret = devm_request_threaded_irq(&pdev->dev,
+                                       tegra->edp_irq,
+                                       soctherm_edp_isr,
+                                       soctherm_edp_isr_thread,
+                                       IRQF_ONESHOT,
+                                       "soctherm_edp",
+                                       tegra);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "request_irq 'edp_irq' failed.\n");
+               return ret;
+       }
+
        return 0;
 }