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authorDaniel Kurtz <djkurtz@chromium.org>2017-04-21 14:11:51 +0800
committerAaron Durbin <adurbin@chromium.org>2017-04-24 22:15:59 +0200
commitc4852e71579cd4b1a702dccae63d5c39f59cade6 (patch)
treeb82ece685e04e650093b6b4bca9ca774516b0e7d /src/drivers/i2c
parented644b1803a4a832ffadbe73dd957dd220d246dc (diff)
downloadcoreboot-c4852e71579cd4b1a702dccae63d5c39f59cade6.tar.xz
drivers/i2c/tpm/cr50: Use tis_plat_irq_status for Cr50 IRQ status
The Cr50 TPM uses an IRQ to provide a "status" signal used for hand-shaking the reception of commands. Real IRQs are not supported in firmware, however firmware can still poll interrupt status registers for the same effect. Commit 94cc485338a3 ("drivers/i2c/tpm/cr50: Support interrupts for status") added support for the Cr50 driver on X86 platforms to use a KConfig file to supply an IRQ which it would poll using acpi_get_gpe. If the IRQ is not supplied, the Cr50 driver inserts a 20 ms wait. Unfortunately this doesn't work so well when using the i2c connected Cr50 on ARM platforms. Luckily, a more generic implementation to allow a mainboard to supply a Cr50 IRQ status polling function was solved for SPI connected Cr50s by commit 19e3d335bddb ("drivers/spi/tpm: using tpm irq to sync tpm transaction"). Let's refactor the i2c c50 driver to use this same approach, and change eve and reef boards to make use of DRIVER_TPM_TIS_ACPI_INTERRUPT for specifying the TPM flow control interrupt. This essentially reverts these two commits: 48f708d199 drivers/i2c/tpm/cr50: Initialize IRQ status handler before probe 94cc485338 drivers/i2c/tpm/cr50: Support interrupts for status And ports this commit to i2c/tpm/cr50: 19e3d335bd drivers/spi/tpm: using tpm irq to sync tpm transaction As a side effect the tpm_vendor_specific IRQ field goes back to its original usage as the "TPM 1.2 command complete" interrupt, instead of being repurposed to hold the flow control IRQ. BRANCH=none BUG=b:36786804 TEST=Boot reef w/ serial enabled firmware, verify verstage sees "cr50 TPM" and does not complain about lack of tis_plat_irq_status(). TEST=Boot eve w/ serial enabled firmware, verify verstage sees "cr50 TPM" and does not complain about lack of tis_plat_irq_status(). Change-Id: I004329eae1d8aabda51c46b8504bf210484782b4 Signed-off-by: Daniel Kurtz <djkurtz@chromium.org> Reviewed-on: https://review.coreboot.org/19363 Reviewed-by: Julius Werner <jwerner@chromium.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org> Tested-by: build bot (Jenkins)
Diffstat (limited to 'src/drivers/i2c')
-rw-r--r--src/drivers/i2c/tpm/Kconfig5
-rw-r--r--src/drivers/i2c/tpm/cr50.c59
-rw-r--r--src/drivers/i2c/tpm/tpm.h1
3 files changed, 18 insertions, 47 deletions
diff --git a/src/drivers/i2c/tpm/Kconfig b/src/drivers/i2c/tpm/Kconfig
index 9e3a0aa82e..db6777e65d 100644
--- a/src/drivers/i2c/tpm/Kconfig
+++ b/src/drivers/i2c/tpm/Kconfig
@@ -44,11 +44,6 @@ config DRIVER_TPM_I2C_ADDR
default 0x2 # FIXME, workaround for Kconfig BS
depends on I2C_TPM
-config DRIVER_TPM_I2C_IRQ
- int "IRQ or GPE to use for TPM interrupt"
- default -1
- depends on I2C_TPM
-
config DRIVER_I2C_TPM_ACPI
depends on I2C_TPM
bool "Generate I2C TPM ACPI device"
diff --git a/src/drivers/i2c/tpm/cr50.c b/src/drivers/i2c/tpm/cr50.c
index ce30bf1b7c..aa59f1e917 100644
--- a/src/drivers/i2c/tpm/cr50.c
+++ b/src/drivers/i2c/tpm/cr50.c
@@ -42,10 +42,6 @@
#include <tpm.h>
#include "tpm.h"
-#if IS_ENABLED(CONFIG_ARCH_X86)
-#include <arch/acpi.h>
-#endif
-
#define CR50_MAX_BUFSIZE 63
#define CR50_TIMEOUT_LONG_MS 2000 /* Long timeout while waiting for TPM */
#define CR50_TIMEOUT_SHORT_MS 2 /* Short timeout during transactions */
@@ -61,33 +57,33 @@ struct tpm_inf_dev {
static struct tpm_inf_dev g_tpm_dev CAR_GLOBAL;
+__attribute__ ((weak)) int tis_plat_irq_status(void)
+{
+ static int warning_displayed CAR_GLOBAL;
+
+ if (!car_get_var(warning_displayed)) {
+ printk(BIOS_WARNING, "WARNING: tis_plat_irq_status() not implemented, wasting 20ms to wait on Cr50!\n");
+ car_set_var(warning_displayed, 1);
+ }
+ mdelay(CR50_TIMEOUT_NOIRQ_MS);
+
+ return 1;
+}
+
/* Wait for interrupt to indicate the TPM is ready */
static int cr50_i2c_wait_tpm_ready(struct tpm_chip *chip)
{
struct stopwatch sw;
- if (!chip->vendor.irq_status) {
- /* Fixed delay if interrupt not supported */
- mdelay(CR50_TIMEOUT_NOIRQ_MS);
- return 0;
- }
-
stopwatch_init_msecs_expire(&sw, CR50_TIMEOUT_IRQ_MS);
- while (!chip->vendor.irq_status(chip->vendor.irq))
+ while (!tis_plat_irq_status())
if (stopwatch_expired(&sw))
return -1;
return 0;
}
-/* Clear pending interrupts */
-static void cr50_i2c_clear_tpm_irq(struct tpm_chip *chip)
-{
- if (chip->vendor.irq_status)
- chip->vendor.irq_status(chip->vendor.irq);
-}
-
/*
* cr50_i2c_read() - read from TPM register
*
@@ -111,7 +107,7 @@ static int cr50_i2c_read(struct tpm_chip *chip, uint8_t addr,
return -1;
/* Clear interrupt before starting transaction */
- cr50_i2c_clear_tpm_irq(chip);
+ tis_plat_irq_status();
/* Send the register address byte to the TPM */
if (i2c_write_raw(tpm_dev->bus, tpm_dev->addr, &addr, 1)) {
@@ -161,7 +157,7 @@ static int cr50_i2c_write(struct tpm_chip *chip,
memcpy(tpm_dev->buf + 1, buffer, len);
/* Clear interrupt before starting transaction */
- cr50_i2c_clear_tpm_irq(chip);
+ tis_plat_irq_status();
/* Send write request buffer with address */
if (i2c_write_raw(tpm_dev->bus, tpm_dev->addr, tpm_dev->buf, len + 1)) {
@@ -418,25 +414,6 @@ static void cr50_vendor_init(struct tpm_chip *chip)
chip->vendor.recv = &cr50_i2c_tis_recv;
chip->vendor.send = &cr50_i2c_tis_send;
chip->vendor.cancel = &cr50_i2c_tis_ready;
- chip->vendor.irq = CONFIG_DRIVER_TPM_I2C_IRQ;
-
- /*
- * Interrupts are not supported this early in firmware,
- * use use an arch-specific method to query for interrupt status.
- */
- if (chip->vendor.irq > 0) {
-#if IS_ENABLED(CONFIG_ARCH_X86)
- /* Query GPE status for interrupt */
- chip->vendor.irq_status = &acpi_get_gpe;
-#else
- chip->vendor.irq = -1;
-#endif
- }
-
- if (chip->vendor.irq <= 0)
- printk(BIOS_WARNING,
- "%s: No IRQ, will use %ums delay for TPM ready\n",
- __func__, CR50_TIMEOUT_NOIRQ_MS);
}
int tpm_vendor_probe(unsigned int bus, uint32_t addr)
@@ -503,8 +480,8 @@ int tpm_vendor_init(struct tpm_chip *chip, unsigned int bus, uint32_t dev_addr)
goto out_err;
}
- printk(BIOS_DEBUG, "cr50 TPM 2.0 (i2c %u:0x%02x irq %d id 0x%x)\n",
- bus, dev_addr, chip->vendor.irq, vendor >> 16);
+ printk(BIOS_DEBUG, "cr50 TPM 2.0 (i2c %u:0x%02x id 0x%x)\n",
+ bus, dev_addr, vendor >> 16);
chip->is_open = 1;
return 0;
diff --git a/src/drivers/i2c/tpm/tpm.h b/src/drivers/i2c/tpm/tpm.h
index e511e0df22..35cf3972cf 100644
--- a/src/drivers/i2c/tpm/tpm.h
+++ b/src/drivers/i2c/tpm/tpm.h
@@ -59,7 +59,6 @@ struct tpm_vendor_specific {
uint8_t req_complete_val;
uint8_t req_canceled;
int irq;
- int (*irq_status)(int irq);
int (*recv)(struct tpm_chip *, uint8_t *, size_t);
int (*send)(struct tpm_chip *, uint8_t *, size_t);
void (*cancel)(struct tpm_chip *);