Merge remote-tracking branch 'remotes/palmer/tags/riscv-for-master-4.2-sf1-v3' into...

RISC-V Patches for the 4.2 Soft Freeze, Part 1, v3

This contains quite a few patches that I'd like to target for 4.2.
They're mostly emulation fixes for the sifive_u board, which now much
more closely matches the hardware and can therefor run the same fireware
as what gets loaded onto the board.  Additional user-visible
improvements include:

* support for loading initrd files from the command line into Linux, via
  /chosen/linux,initrd-{start,end} device tree nodes.
* The conversion of LOG_TRACE to trace events.
* The addition of clock DT nodes for our uart and ethernet.

This also includes some preliminary work for the H extension patches,
but does not include the H extension patches as I haven't had time to
review them yet.

This passes my OE boot test on 32-bit and 64-bit virt machines, as well
as a 64-bit upstream Linux boot on the sifive_u machine.  It has been
fixed to actually pass "make check" this time.

Changes since v2 (never made it to the list):

* Sets the sifive_u machine default core count to 2 instead of 5.

Changes since v1 <20190910190513.21160-1-palmer@sifive.com>:

* Sets the sifive_u machine default core count to 5 instead of 1, as
  it's impossible to have a single core sifive_u machine.

# gpg: Signature made Tue 17 Sep 2019 16:43:30 BST
# gpg:                using RSA key 00CE76D1834960DFCE886DF8EF4CA1502CCBAB41
# gpg:                issuer "palmer@dabbelt.com"
# gpg: Good signature from "Palmer Dabbelt <palmer@dabbelt.com>" [unknown]
# gpg:                 aka "Palmer Dabbelt <palmer@sifive.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 00CE 76D1 8349 60DF CE88  6DF8 EF4C A150 2CCB AB41

* remotes/palmer/tags/riscv-for-master-4.2-sf1-v3: (48 commits)
  gdbstub: riscv: fix the fflags registers
  target/riscv: Use TB_FLAGS_MSTATUS_FS for floating point
  target/riscv: Fix mstatus dirty mask
  target/riscv: Use both register name and ABI name
  riscv: sifive_u: Update model and compatible strings in device tree
  riscv: sifive_u: Remove handcrafted clock nodes for UART and ethernet
  riscv: sifive_u: Fix broken GEM support
  riscv: sifive_u: Instantiate OTP memory with a serial number
  riscv: sifive: Implement a model for SiFive FU540 OTP
  riscv: roms: Update default bios for sifive_u machine
  riscv: sifive_u: Change UART node name in device tree
  riscv: sifive_u: Update UART base addresses and IRQs
  riscv: sifive_u: Reference PRCI clocks in UART and ethernet nodes
  riscv: sifive_u: Add PRCI block to the SoC
  riscv: sifive_u: Generate hfclk and rtcclk nodes
  riscv: sifive: Implement PRCI model for FU540
  riscv: sifive_u: Update PLIC hart topology configuration string
  riscv: sifive_u: Update hart configuration to reflect the real FU540 SoC
  riscv: sifive_u: Set the minimum number of cpus to 2
  riscv: hart: Add a "hartid-base" property to RISC-V hart array
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>