diff options
Diffstat (limited to 'drivers/char/tpm/tpm_tis_core.c')
| -rw-r--r-- | drivers/char/tpm/tpm_tis_core.c | 103 |
1 files changed, 88 insertions, 15 deletions
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index 558144fa707a..88a5384c09c0 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -24,9 +24,12 @@ #include <linux/wait.h> #include <linux/acpi.h> #include <linux/freezer.h> +#include <linux/dmi.h> #include "tpm.h" #include "tpm_tis_core.h" +#define TPM_TIS_MAX_UNHANDLED_IRQS 1000 + static void tpm_tis_clkrun_enable(struct tpm_chip *chip, bool value); static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, @@ -468,25 +471,29 @@ out_err: return rc; } -static void disable_interrupts(struct tpm_chip *chip) +static void __tpm_tis_disable_interrupts(struct tpm_chip *chip) +{ + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); + u32 int_mask = 0; + + tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &int_mask); + int_mask &= ~TPM_GLOBAL_INT_ENABLE; + tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), int_mask); + + chip->flags &= ~TPM_CHIP_FLAG_IRQ; +} + +static void tpm_tis_disable_interrupts(struct tpm_chip *chip) { struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); - u32 intmask; - int rc; if (priv->irq == 0) return; - rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask); - if (rc < 0) - intmask = 0; - - intmask &= ~TPM_GLOBAL_INT_ENABLE; - rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask); + __tpm_tis_disable_interrupts(chip); devm_free_irq(chip->dev.parent, priv->irq, chip); priv->irq = 0; - chip->flags &= ~TPM_CHIP_FLAG_IRQ; } /* @@ -552,7 +559,7 @@ static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len) if (!test_bit(TPM_TIS_IRQ_TESTED, &priv->flags)) tpm_msleep(1); if (!test_bit(TPM_TIS_IRQ_TESTED, &priv->flags)) - disable_interrupts(chip); + tpm_tis_disable_interrupts(chip); set_bit(TPM_TIS_IRQ_TESTED, &priv->flags); return rc; } @@ -752,6 +759,57 @@ static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status) return status == TPM_STS_COMMAND_READY; } +static irqreturn_t tpm_tis_revert_interrupts(struct tpm_chip *chip) +{ + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); + const char *product; + const char *vendor; + + dev_warn(&chip->dev, FW_BUG + "TPM interrupt storm detected, polling instead\n"); + + vendor = dmi_get_system_info(DMI_SYS_VENDOR); + product = dmi_get_system_info(DMI_PRODUCT_VERSION); + + if (vendor && product) { + dev_info(&chip->dev, + "Consider adding the following entry to tpm_tis_dmi_table:\n"); + dev_info(&chip->dev, "\tDMI_SYS_VENDOR: %s\n", vendor); + dev_info(&chip->dev, "\tDMI_PRODUCT_VERSION: %s\n", product); + } + + if (tpm_tis_request_locality(chip, 0) != 0) + return IRQ_NONE; + + __tpm_tis_disable_interrupts(chip); + tpm_tis_relinquish_locality(chip, 0); + + schedule_work(&priv->free_irq_work); + + return IRQ_HANDLED; +} + +static irqreturn_t tpm_tis_update_unhandled_irqs(struct tpm_chip *chip) +{ + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); + irqreturn_t irqret = IRQ_HANDLED; + + if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) + return IRQ_HANDLED; + + if (time_after(jiffies, priv->last_unhandled_irq + HZ/10)) + priv->unhandled_irqs = 1; + else + priv->unhandled_irqs++; + + priv->last_unhandled_irq = jiffies; + + if (priv->unhandled_irqs > TPM_TIS_MAX_UNHANDLED_IRQS) + irqret = tpm_tis_revert_interrupts(chip); + + return irqret; +} + static irqreturn_t tis_int_handler(int dummy, void *dev_id) { struct tpm_chip *chip = dev_id; @@ -761,10 +819,10 @@ static irqreturn_t tis_int_handler(int dummy, void *dev_id) rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt); if (rc < 0) - return IRQ_NONE; + goto err; if (interrupt == 0) - return IRQ_NONE; + goto err; set_bit(TPM_TIS_IRQ_TESTED, &priv->flags); if (interrupt & TPM_INTF_DATA_AVAIL_INT) @@ -780,10 +838,13 @@ static irqreturn_t tis_int_handler(int dummy, void *dev_id) rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), interrupt); tpm_tis_relinquish_locality(chip, 0); if (rc < 0) - return IRQ_NONE; + goto err; tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt); return IRQ_HANDLED; + +err: + return tpm_tis_update_unhandled_irqs(chip); } static void tpm_tis_gen_interrupt(struct tpm_chip *chip) @@ -804,6 +865,15 @@ static void tpm_tis_gen_interrupt(struct tpm_chip *chip) chip->flags &= ~TPM_CHIP_FLAG_IRQ; } +static void tpm_tis_free_irq_func(struct work_struct *work) +{ + struct tpm_tis_data *priv = container_of(work, typeof(*priv), free_irq_work); + struct tpm_chip *chip = priv->chip; + + devm_free_irq(chip->dev.parent, priv->irq, chip); + priv->irq = 0; +} + /* Register the IRQ and issue a command that will cause an interrupt. If an * irq is seen then leave the chip setup for IRQ operation, otherwise reverse * everything and leave in polling mode. Returns 0 on success. @@ -816,6 +886,7 @@ static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask, int rc; u32 int_status; + INIT_WORK(&priv->free_irq_work, tpm_tis_free_irq_func); rc = devm_request_threaded_irq(chip->dev.parent, irq, NULL, tis_int_handler, IRQF_ONESHOT | flags, @@ -918,6 +989,7 @@ void tpm_tis_remove(struct tpm_chip *chip) interrupt = 0; tpm_tis_write32(priv, reg, ~TPM_GLOBAL_INT_ENABLE & interrupt); + flush_work(&priv->free_irq_work); tpm_tis_clkrun_enable(chip, false); @@ -1021,6 +1093,7 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, chip->timeout_b = msecs_to_jiffies(TIS_TIMEOUT_B_MAX); chip->timeout_c = msecs_to_jiffies(TIS_TIMEOUT_C_MAX); chip->timeout_d = msecs_to_jiffies(TIS_TIMEOUT_D_MAX); + priv->chip = chip; priv->timeout_min = TPM_TIMEOUT_USECS_MIN; priv->timeout_max = TPM_TIMEOUT_USECS_MAX; priv->phy_ops = phy_ops; @@ -1179,7 +1252,7 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, rc = tpm_tis_request_locality(chip, 0); if (rc < 0) goto out_err; - disable_interrupts(chip); + tpm_tis_disable_interrupts(chip); tpm_tis_relinquish_locality(chip, 0); } } |