1. 17 Mar, 2020 5 commits
    • Andre Przywara's avatar
      rpi: console: Autodetect Mini-UART vs. PL011 configuration · 9cc3fa1b
      Andre Przywara authored
      
      
      The Raspberry Pi has two different UART devices pin-muxed to GPIO 14&15:
      One ARM PL011 one and the 8250 compatible "Mini-UART".
      A dtoverlay parameter in config.txt will tell the firmware to switch
      between the two: it will setup the right clocks and will configure the
      pinmuxes accordingly.
      
      To autodetect the user's choice, we read the pinmux register and check
      its setting: ALT5 (0x2) means the Mini-UART is used, ALT0 (0x4) points
      to the PL011.
      Based on that we select the UART driver to initialise.
      
      This will allow console output in any case.
      
      Change-Id: I620d3ce68de6c6576599f2a405636020e1fd1376
      Signed-off-by: default avatarAndre Przywara <andre.przywara@arm.com>
      9cc3fa1b
    • Andre Przywara's avatar
      rpi3: build: Include GPIO driver in all BL stages · 29e8c460
      Andre Przywara authored
      
      
      So far the Raspberry Pi 3 build needs the GPIO driver just for BL2.
      Upcoming changes will require some GPIO code in BL1 and BL31 also, so
      move those driver files into the common source section.
      
      This does not affect BL31 code size at all, and bl1.bin just increases
      by 144 bytes, but doesn't affect the padded binary size at all.
      Signed-off-by: default avatarAndre Przywara <andre.przywara@arm.com>
      Change-Id: I7639746dc241c1e69099d85d2671c65fa0108555
      29e8c460
    • Andre Przywara's avatar
      rpi: Allow using PL011 UART for RPi3/RPi4 · 5e6d821c
      Andre Przywara authored
      
      
      The Broadcom 283x SoCs feature multiple UARTs: the mostly used
      "Mini-UART", which is an 8250 compatible IP, and at least one PL011.
      While the 8250 is usually used for serial console purposes, it suffers
      from a design flaw, where its clock depends on the VPU clock, which can
      change at runtime. This will reliably mess up the baud rate.
      To avoid this problem, people might choose to use the PL011 UART for
      the serial console, which is pin-mux'ed to the very same GPIO pins.
      This can be done by adding "miniuart-bt" to the "dtoverlay=" line in
      config.txt.
      
      To prepare for this situation, use the newly gained freedom of sharing
      one console_t pointer across different UART drivers, to introduce the
      option of choosing the PL011 for the console.
      
      This is for now hard-coded to choose the Mini-UART by default.
      A follow-up patch will introduce automatic detection.
      Signed-off-by: default avatarAndre Przywara <andre.przywara@arm.com>
      Change-Id: I8cf2522151e09ff4ff94a6d396aec6fc4b091a05
      5e6d821c
    • Andre Przywara's avatar
      rpi3: console: Use same "clock-less" setup scheme as RPi4 · 795aefe5
      Andre Przywara authored
      
      
      In the wake of the upcoming unification of the console setup code
      between RPi3 and RPi4, extend the "clock-less" setup scheme to the
      RPi3. This avoid programming any clocks or baud rate registers,
      which makes the port more robust against GPU firmware changes.
      Signed-off-by: default avatarAndre Przywara <andre.przywara@arm.com>
      Change-Id: Ida83a963bb18a878997e9cbd55f8ceac6a2e1c1f
      795aefe5
    • Andre Przywara's avatar
      rpi3: gpio: Simplify GPIO setup · 0d92745e
      Andre Przywara authored
      
      
      There is really no reason to use and pass around a struct when its only
      member is the (fixed) base address.
      
      Remove the struct and just use the base address on its own inside the
      GPIO driver. Then set the base address automatically.
      
      This simplifies GPIO setup for users, which now don't need to deal with
      zeroing a struct and setting the base address anymore.
      
      Change-Id: I3060f7859e3f8ef9a24cc8fb38307b5da943f127
      Signed-off-by: default avatarAndre Przywara <andre.przywara@arm.com>
      0d92745e
  2. 11 Mar, 2020 12 commits
  3. 10 Mar, 2020 5 commits
  4. 09 Mar, 2020 18 commits