On Raspberry Pi platform GPIO controller also responsible for pins
multiplexing. Pi code predates proper FDT support in FreeBSD so a
lot of pinmux info is hardcoded. This patch:
- Implements pinctl methods in bcm2835_gpio
- Converts all devices with ad-hoc pinmux info to proper pin control
mechanisms and adds pinmux info in FreeBSD's custom dts files.
- Adds fdt_pinctrl option to RPI2 and RPI-B kernels
- Adds SPI pinmux config to FreeBSD's customization of GNU DTS.
Reviewed by: imp, manu
Differential Revision: https://reviews.freebsd.org/D14104
Upstream DTBs don't provide IRQ lines for the RNG. Moreover, harvesting
bytes as often as the RNG interrupt is triggered (87 times per sec) is an
overkill.
For these reasons, get rid of the interrupt mode and make callout mode the
default, with random bits harvested every 4 seconds.
Submitted by: Sylvain Garrigues <sylgar@gmail.com>
Reviewed by: ian, imp, manu, mmel
Approved by: emaste
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D14541
