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 94cc485338 ("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 19e3d335bd ("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)
c4852e7157