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path: root/drivers/char/tpm/tpm_tis_core.c
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Diffstat (limited to 'drivers/char/tpm/tpm_tis_core.c')
-rw-r--r--drivers/char/tpm/tpm_tis_core.c172
1 files changed, 139 insertions, 33 deletions
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 558144fa707a..1b350412d8a6 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,
@@ -337,7 +340,7 @@ static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
return size;
}
-static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
+static int tpm_tis_try_recv(struct tpm_chip *chip, u8 *buf, size_t count)
{
struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
int size = 0;
@@ -345,11 +348,6 @@ static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
u32 expected;
int rc;
- if (count < TPM_HEADER_SIZE) {
- size = -EIO;
- goto out;
- }
-
size = recv_data(chip, buf, TPM_HEADER_SIZE);
/* read first 10 bytes, including tag, paramsize, and result */
if (size < TPM_HEADER_SIZE) {
@@ -363,8 +361,13 @@ static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
goto out;
}
- size += recv_data(chip, &buf[TPM_HEADER_SIZE],
- expected - TPM_HEADER_SIZE);
+ rc = recv_data(chip, &buf[TPM_HEADER_SIZE],
+ expected - TPM_HEADER_SIZE);
+ if (rc < 0) {
+ size = rc;
+ goto out;
+ }
+ size += rc;
if (size < expected) {
dev_err(&chip->dev, "Unable to read remainder of result\n");
size = -ETIME;
@@ -377,7 +380,7 @@ static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
goto out;
}
status = tpm_tis_status(chip);
- if (status & TPM_STS_DATA_AVAIL) { /* retry? */
+ if (status & TPM_STS_DATA_AVAIL) {
dev_err(&chip->dev, "Error left over data\n");
size = -EIO;
goto out;
@@ -391,10 +394,36 @@ static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
}
out:
- tpm_tis_ready(chip);
return size;
}
+static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
+{
+ struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+ unsigned int try;
+ int rc = 0;
+
+ if (count < TPM_HEADER_SIZE)
+ return -EIO;
+
+ for (try = 0; try < TPM_RETRY; try++) {
+ rc = tpm_tis_try_recv(chip, buf, count);
+
+ if (rc == -EIO)
+ /* Data transfer errors, indicated by EIO, can be
+ * recovered by rereading the response.
+ */
+ tpm_tis_write8(priv, TPM_STS(priv->locality),
+ TPM_STS_RESPONSE_RETRY);
+ else
+ break;
+ }
+
+ tpm_tis_ready(chip);
+
+ return rc;
+}
+
/*
* If interrupts are used (signaled by an irq set in the vendor structure)
* tpm.c can skip polling for the data to be available as the interrupt is
@@ -461,6 +490,12 @@ static int tpm_tis_send_data(struct tpm_chip *chip, const u8 *buf, size_t len)
goto out_err;
}
+ rc = tpm_tis_verify_crc(priv, len, buf);
+ if (rc < 0) {
+ dev_err(&chip->dev, "CRC mismatch for command.\n");
+ goto out_err;
+ }
+
return 0;
out_err:
@@ -468,25 +503,29 @@ 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;
}
/*
@@ -500,15 +539,16 @@ static int tpm_tis_send_main(struct tpm_chip *chip, const u8 *buf, size_t len)
int rc;
u32 ordinal;
unsigned long dur;
+ unsigned int try;
- rc = tpm_tis_send_data(chip, buf, len);
- if (rc < 0)
- return rc;
-
- rc = tpm_tis_verify_crc(priv, len, buf);
- if (rc < 0) {
- dev_err(&chip->dev, "CRC mismatch for command.\n");
- return rc;
+ for (try = 0; try < TPM_RETRY; try++) {
+ rc = tpm_tis_send_data(chip, buf, len);
+ if (rc >= 0)
+ /* Data transfer done successfully */
+ break;
+ else if (rc != -EIO)
+ /* Data transfer failed, not recoverable */
+ return rc;
}
/* go and do it */
@@ -552,7 +592,7 @@ 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 +792,57 @@ 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 +852,10 @@ 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 +871,13 @@ 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 +898,15 @@ 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 +919,7 @@ 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 +1022,7 @@ 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 +1126,7 @@ 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 +1285,7 @@ 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);
}
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-07-11 23:30:38 +0300