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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
commit03dd4cb26d967f9588437b0fc9cc0e8353322bb7 (patch)
treefa581f6dc1c0596391690d1f67eceef3af8246dc /drivers/char/tpm/tpm_tis.c
parentd4e493caf788ef44982e131ff9c786546904d934 (diff)
Linux-libre 4.5-gnu
Diffstat (limited to 'drivers/char/tpm/tpm_tis.c')
-rw-r--r--drivers/char/tpm/tpm_tis.c256
1 files changed, 109 insertions, 147 deletions
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index 65f7eecc4..8a3509cb1 100644
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -401,7 +401,7 @@ static void disable_interrupts(struct tpm_chip *chip)
iowrite32(intmask,
chip->vendor.iobase +
TPM_INT_ENABLE(chip->vendor.locality));
- free_irq(chip->vendor.irq, chip);
+ devm_free_irq(chip->pdev, chip->vendor.irq, chip);
chip->vendor.irq = 0;
}
@@ -461,11 +461,8 @@ static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
chip->vendor.irq = irq;
if (!priv->irq_tested)
msleep(1);
- if (!priv->irq_tested) {
+ if (!priv->irq_tested)
disable_interrupts(chip);
- dev_err(chip->pdev,
- FW_BUG "TPM interrupt not working, polling instead\n");
- }
priv->irq_tested = true;
return rc;
}
@@ -570,26 +567,6 @@ static const struct tpm_class_ops tpm_tis = {
.req_canceled = tpm_tis_req_canceled,
};
-static irqreturn_t tis_int_probe(int irq, void *dev_id)
-{
- struct tpm_chip *chip = dev_id;
- u32 interrupt;
-
- interrupt = ioread32(chip->vendor.iobase +
- TPM_INT_STATUS(chip->vendor.locality));
-
- if (interrupt == 0)
- return IRQ_NONE;
-
- chip->vendor.probed_irq = irq;
-
- /* Clear interrupts handled with TPM_EOI */
- iowrite32(interrupt,
- chip->vendor.iobase +
- TPM_INT_STATUS(chip->vendor.locality));
- return IRQ_HANDLED;
-}
-
static irqreturn_t tis_int_handler(int dummy, void *dev_id)
{
struct tpm_chip *chip = dev_id;
@@ -622,6 +599,84 @@ static irqreturn_t tis_int_handler(int dummy, void *dev_id)
return IRQ_HANDLED;
}
+/* 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.
+ */
+static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
+ int flags, int irq)
+{
+ struct priv_data *priv = chip->vendor.priv;
+ u8 original_int_vec;
+
+ if (devm_request_irq(chip->pdev, irq, tis_int_handler, flags,
+ chip->devname, chip) != 0) {
+ dev_info(chip->pdev, "Unable to request irq: %d for probe\n",
+ irq);
+ return -1;
+ }
+ chip->vendor.irq = irq;
+
+ original_int_vec = ioread8(chip->vendor.iobase +
+ TPM_INT_VECTOR(chip->vendor.locality));
+ iowrite8(irq,
+ chip->vendor.iobase + TPM_INT_VECTOR(chip->vendor.locality));
+
+ /* Clear all existing */
+ iowrite32(ioread32(chip->vendor.iobase +
+ TPM_INT_STATUS(chip->vendor.locality)),
+ chip->vendor.iobase + TPM_INT_STATUS(chip->vendor.locality));
+
+ /* Turn on */
+ iowrite32(intmask | TPM_GLOBAL_INT_ENABLE,
+ chip->vendor.iobase + TPM_INT_ENABLE(chip->vendor.locality));
+
+ priv->irq_tested = false;
+
+ /* Generate an interrupt by having the core call through to
+ * tpm_tis_send
+ */
+ if (chip->flags & TPM_CHIP_FLAG_TPM2)
+ tpm2_gen_interrupt(chip);
+ else
+ tpm_gen_interrupt(chip);
+
+ /* tpm_tis_send will either confirm the interrupt is working or it
+ * will call disable_irq which undoes all of the above.
+ */
+ if (!chip->vendor.irq) {
+ iowrite8(original_int_vec,
+ chip->vendor.iobase +
+ TPM_INT_VECTOR(chip->vendor.locality));
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Try to find the IRQ the TPM is using. This is for legacy x86 systems that
+ * do not have ACPI/etc. We typically expect the interrupt to be declared if
+ * present.
+ */
+static void tpm_tis_probe_irq(struct tpm_chip *chip, u32 intmask)
+{
+ u8 original_int_vec;
+ int i;
+
+ original_int_vec = ioread8(chip->vendor.iobase +
+ TPM_INT_VECTOR(chip->vendor.locality));
+
+ if (!original_int_vec) {
+ if (IS_ENABLED(CONFIG_X86))
+ for (i = 3; i <= 15; i++)
+ if (!tpm_tis_probe_irq_single(chip, intmask, 0,
+ i))
+ return;
+ } else if (!tpm_tis_probe_irq_single(chip, intmask, 0,
+ original_int_vec))
+ return;
+}
+
static bool interrupts = true;
module_param(interrupts, bool, 0444);
MODULE_PARM_DESC(interrupts, "Enable interrupts");
@@ -644,8 +699,7 @@ static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
acpi_handle acpi_dev_handle)
{
u32 vendor, intfcaps, intmask;
- int rc, i, irq_s, irq_e, probe;
- int irq_r = -1;
+ int rc, probe;
struct tpm_chip *chip;
struct priv_data *priv;
@@ -677,6 +731,15 @@ static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
goto out_err;
}
+ /* Take control of the TPM's interrupt hardware and shut it off */
+ intmask = ioread32(chip->vendor.iobase +
+ TPM_INT_ENABLE(chip->vendor.locality));
+ intmask |= TPM_INTF_CMD_READY_INT | TPM_INTF_LOCALITY_CHANGE_INT |
+ TPM_INTF_DATA_AVAIL_INT | TPM_INTF_STS_VALID_INT;
+ intmask &= ~TPM_GLOBAL_INT_ENABLE;
+ iowrite32(intmask,
+ chip->vendor.iobase + TPM_INT_ENABLE(chip->vendor.locality));
+
if (request_locality(chip, 0) != 0) {
rc = -ENODEV;
goto out_err;
@@ -731,126 +794,31 @@ static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
if (intfcaps & TPM_INTF_DATA_AVAIL_INT)
dev_dbg(dev, "\tData Avail Int Support\n");
+ /* Very early on issue a command to the TPM in polling mode to make
+ * sure it works. May as well use that command to set the proper
+ * timeouts for the driver.
+ */
+ if (tpm_get_timeouts(chip)) {
+ dev_err(dev, "Could not get TPM timeouts and durations\n");
+ rc = -ENODEV;
+ goto out_err;
+ }
+
/* INTERRUPT Setup */
init_waitqueue_head(&chip->vendor.read_queue);
init_waitqueue_head(&chip->vendor.int_queue);
-
- intmask =
- ioread32(chip->vendor.iobase +
- TPM_INT_ENABLE(chip->vendor.locality));
-
- intmask |= TPM_INTF_CMD_READY_INT
- | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT
- | TPM_INTF_STS_VALID_INT;
-
- iowrite32(intmask,
- chip->vendor.iobase +
- TPM_INT_ENABLE(chip->vendor.locality));
- if (interrupts)
- chip->vendor.irq = tpm_info->irq;
- if (interrupts && !chip->vendor.irq) {
- irq_s =
- ioread8(chip->vendor.iobase +
- TPM_INT_VECTOR(chip->vendor.locality));
- irq_r = irq_s;
- if (irq_s) {
- irq_e = irq_s;
- } else {
- irq_s = 3;
- irq_e = 15;
- }
-
- for (i = irq_s; i <= irq_e && chip->vendor.irq == 0; i++) {
- iowrite8(i, chip->vendor.iobase +
- TPM_INT_VECTOR(chip->vendor.locality));
- if (devm_request_irq
- (dev, i, tis_int_probe, IRQF_SHARED,
- chip->devname, chip) != 0) {
- dev_info(chip->pdev,
- "Unable to request irq: %d for probe\n",
- i);
- continue;
- }
-
- /* Clear all existing */
- iowrite32(ioread32
- (chip->vendor.iobase +
- TPM_INT_STATUS(chip->vendor.locality)),
- chip->vendor.iobase +
- TPM_INT_STATUS(chip->vendor.locality));
-
- /* Turn on */
- iowrite32(intmask | TPM_GLOBAL_INT_ENABLE,
- chip->vendor.iobase +
- TPM_INT_ENABLE(chip->vendor.locality));
-
- chip->vendor.probed_irq = 0;
-
- /* Generate Interrupts */
- if (chip->flags & TPM_CHIP_FLAG_TPM2)
- tpm2_gen_interrupt(chip);
- else
- tpm_gen_interrupt(chip);
-
- chip->vendor.irq = chip->vendor.probed_irq;
-
- /* free_irq will call into tis_int_probe;
- clear all irqs we haven't seen while doing
- tpm_gen_interrupt */
- iowrite32(ioread32
- (chip->vendor.iobase +
- TPM_INT_STATUS(chip->vendor.locality)),
- chip->vendor.iobase +
- TPM_INT_STATUS(chip->vendor.locality));
-
- /* Turn off */
- iowrite32(intmask,
- chip->vendor.iobase +
- TPM_INT_ENABLE(chip->vendor.locality));
-
- devm_free_irq(dev, i, chip);
- }
+ if (interrupts) {
+ if (tpm_info->irq) {
+ tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED,
+ tpm_info->irq);
+ if (!chip->vendor.irq)
+ dev_err(chip->pdev, FW_BUG
+ "TPM interrupt not working, polling instead\n");
+ } else
+ tpm_tis_probe_irq(chip, intmask);
}
- if (chip->vendor.irq) {
- iowrite8(chip->vendor.irq,
- chip->vendor.iobase +
- TPM_INT_VECTOR(chip->vendor.locality));
- if (devm_request_irq
- (dev, chip->vendor.irq, tis_int_handler, IRQF_SHARED,
- chip->devname, chip) != 0) {
- dev_info(chip->pdev,
- "Unable to request irq: %d for use\n",
- chip->vendor.irq);
- chip->vendor.irq = 0;
- } else {
- /* Clear all existing */
- iowrite32(ioread32
- (chip->vendor.iobase +
- TPM_INT_STATUS(chip->vendor.locality)),
- chip->vendor.iobase +
- TPM_INT_STATUS(chip->vendor.locality));
-
- /* Turn on */
- iowrite32(intmask | TPM_GLOBAL_INT_ENABLE,
- chip->vendor.iobase +
- TPM_INT_ENABLE(chip->vendor.locality));
- }
- } else if (irq_r != -1)
- iowrite8(irq_r, chip->vendor.iobase +
- TPM_INT_VECTOR(chip->vendor.locality));
if (chip->flags & TPM_CHIP_FLAG_TPM2) {
- chip->vendor.timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
- chip->vendor.timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
- chip->vendor.timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
- chip->vendor.timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
- chip->vendor.duration[TPM_SHORT] =
- msecs_to_jiffies(TPM2_DURATION_SHORT);
- chip->vendor.duration[TPM_MEDIUM] =
- msecs_to_jiffies(TPM2_DURATION_MEDIUM);
- chip->vendor.duration[TPM_LONG] =
- msecs_to_jiffies(TPM2_DURATION_LONG);
-
rc = tpm2_do_selftest(chip);
if (rc == TPM2_RC_INITIALIZE) {
dev_warn(dev, "Firmware has not started TPM\n");
@@ -866,12 +834,6 @@ static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
goto out_err;
}
} else {
- if (tpm_get_timeouts(chip)) {
- dev_err(dev, "Could not get TPM timeouts and durations\n");
- rc = -ENODEV;
- goto out_err;
- }
-
if (tpm_do_selftest(chip)) {
dev_err(dev, "TPM self test failed\n");
rc = -ENODEV;