From: Jerry Snitselaar jsnitsel@redhat.com
[ Upstream commit b154ce11ead925de6a94feb3b0317fafeefa0ebc ]
There is a misconfiguration in the bios of the gpio pin used for the interrupt in the T490s. When interrupts are enabled in the tpm_tis driver code this results in an interrupt storm. This was initially reported when we attempted to enable the interrupt code in the tpm_tis driver, which previously wasn't setting a flag to enable it. Due to the reports of the interrupt storm that code was reverted and we went back to polling instead of using interrupts. Now that we know the T490s problem is a firmware issue, add code to check if the system is a T490s and disable interrupts if that is the case. This will allow us to enable interrupts for everyone else. If the user has a fixed bios they can force the enabling of interrupts with tpm_tis.interrupts=1 on the kernel command line.
Cc: Peter Huewe peterhuewe@gmx.de Cc: Jason Gunthorpe jgg@ziepe.ca Cc: Hans de Goede hdegoede@redhat.com Signed-off-by: Jerry Snitselaar jsnitsel@redhat.com Reviewed-by: James Bottomley James.Bottomley@HansenPartnership.com Reviewed-by: Hans de Goede hdegoede@redhat.com Reviewed-by: Jarkko Sakkinen jarkko@kernel.org Signed-off-by: Jarkko Sakkinen jarkko@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/char/tpm/tpm_tis.c | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-)
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c index f08949a5f678..5a3a4f095391 100644 --- a/drivers/char/tpm/tpm_tis.c +++ b/drivers/char/tpm/tpm_tis.c @@ -31,6 +31,7 @@ #include <linux/of.h> #include <linux/of_device.h> #include <linux/kernel.h> +#include <linux/dmi.h> #include "tpm.h" #include "tpm_tis_core.h"
@@ -53,8 +54,8 @@ static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *da return container_of(data, struct tpm_tis_tcg_phy, priv); }
-static bool interrupts = true; -module_param(interrupts, bool, 0444); +static int interrupts = -1; +module_param(interrupts, int, 0444); MODULE_PARM_DESC(interrupts, "Enable interrupts");
static bool itpm; @@ -67,6 +68,28 @@ module_param(force, bool, 0444); MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry"); #endif
+static int tpm_tis_disable_irq(const struct dmi_system_id *d) +{ + if (interrupts == -1) { + pr_notice("tpm_tis: %s detected: disabling interrupts.\n", d->ident); + interrupts = 0; + } + + return 0; +} + +static const struct dmi_system_id tpm_tis_dmi_table[] = { + { + .callback = tpm_tis_disable_irq, + .ident = "ThinkPad T490s", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T490s"), + }, + }, + {} +}; + #if defined(CONFIG_PNP) && defined(CONFIG_ACPI) static int has_hid(struct acpi_device *dev, const char *hid) { @@ -196,6 +219,8 @@ static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info) int irq = -1; int rc;
+ dmi_check_system(tpm_tis_dmi_table); + rc = check_acpi_tpm2(dev); if (rc) return rc;