| commit | 96c4882d257c611bb1a3d18ad2f1b60041582022 | [log] [tgz] |
|---|---|---|
| author | Felix Held <felix-coreboot@felixheld.de> | Mon Aug 02 19:48:40 2021 +0200 |
| committer | Felix Held <felix-coreboot@felixheld.de> | Wed Sep 08 00:14:35 2021 +0000 |
| tree | 7ff7b02c9b322c5b6c5215da894bc639e34c0518 | |
| parent | 916cd50edc90bc9edd134d6a37911174cc0ff944 [diff] |
soc/amd/common/block/i2c: use common GPIO API in drive_scl No need to do raw GPIO MMIO accesses when basically the same functionality can be achieved by using existing APIs. Using the existing GPIO API instead of raw GPIO MMIO register accesses allows containing all direct GPIO MMIO accesses inside the common AMD GPIO code which will be done in subsequent patches. Since the value parameter of gpio_set is int, change the type of the val parameter of drive_scl to int as well even though I'm not sure why a signed integer was used for this in the common GPIO API. Since program_gpios already configures the SCL GPIOs as outputs, gpio_set can be used in drive_scl which only sets the output value, but doesn't configure the direction. TEST=The waveform on the SCL pin of I2C3 on a barla/careena Chromebook looks similar to the same as before during the reset_i2c_peripherals call, but due to the additional overhead of the read-modify-write to the GPIO register instead of just a write, the pulse width gets about 50% longer. Since the udelay call in drive_scl still has an open TODO to make this configurable and the pulses being longer is in the safe side, this side-effect can be addressed in a follow-up patch. Signed-off-by: Felix Held <felix-coreboot@felixheld.de> Change-Id: Ic323cebc1c83ecd6f0e1fbab419c69489d77face Reviewed-on: https://review.coreboot.org/c/coreboot/+/56777 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Raul Rangel <rrangel@chromium.org>
coreboot is a Free Software project aimed at replacing the proprietary BIOS (firmware) found in most computers. coreboot performs a little bit of hardware initialization and then executes additional boot logic, called a payload.
With the separation of hardware initialization and later boot logic, coreboot can scale from specialized applications that run directly firmware, run operating systems in flash, load custom bootloaders, or implement firmware standards, like PC BIOS services or UEFI. This allows for systems to only include the features necessary in the target application, reducing the amount of code and flash space required.
coreboot was formerly known as LinuxBIOS.
After the basic initialization of the hardware has been performed, any desired "payload" can be started by coreboot.
See https://www.coreboot.org/Payloads for a list of supported payloads.
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For details please consult:
ANY_TOOLCHAIN Kconfig option if you're feeling lucky (no support in this case).Optional:
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