[PATCH v3 0/9] hw/riscv: sifive_u: Add missing SPI support

[Bin Meng <bmeng.cn@gmail.com>]

From: Bin Meng <bin.meng@windriver.com>

This adds the missing SPI support to the `sifive_u` machine in the QEMU
mainline. With this series, upstream U-Boot for the SiFive HiFive Unleashed
board can boot on QEMU `sifive_u` out of the box. This allows users to
develop and test the recommended RISC-V boot flow with a real world use
case: ZSBL (in QEMU) loads U-Boot SPL from SD card or SPI flash to L2LIM,
then U-Boot SPL loads the payload from SD card or SPI flash that is a
combination of OpenSBI fw_dynamic firmware and U-Boot proper.

The m25p80 model is updated to support ISSI flash series. A bunch of
ssi-sd issues are fixed, and writing to SD card in SPI mode is supported.

Note the ssi-sd changes are split out of this series in v3, so that all
patches in v3 can go via Alistair's riscv tree.

Part of the ssi-sd changes are now in qemu/master. The remaining patches
are http://patchwork.ozlabs.org/project/qemu-devel/list/?series=226136
that will go via Philippe's sd tree.

reST documentation for RISC-V is added. Currently only `sifive_u`
machine is documented, but more to come.

Changes in v3:
- Simplify flush txfifo logic
- Convert sifive_u.rst from UTF-8 to ASCII

Changes in v2:
- Mention QPI (Quad Peripheral Interface) mode is not supported
- Log guest error when trying to write reserved registers
- Log guest error when trying to access out-of-bounds registers
- log guest error when writing to reserved bits for chip select
  registers and watermark registers
- Log unimplemented warning when trying to write direct-map flash
  interface registers
- Add test tx fifo full logic in sifive_spi_read(), hence remove
  setting the tx fifo full flag in sifive_spi_write().
- Populate register with their default value
- Correct the "connects" typo in the commit message
- Mention in the commit message that <reg> property does not populate
  the second group which represents the memory mapped address of the
  SPI flash
- Correct the "connects" typo in the commit message
- Correct several typos in sifive_u.rst
- Update doc to mention U-Boot v2021.01

Bin Meng (9):
  hw/block: m25p80: Add ISSI SPI flash support
  hw/block: m25p80: Add various ISSI flash information
  hw/ssi: Add SiFive SPI controller support
  hw/riscv: sifive_u: Add QSPI0 controller and connect a flash
  hw/riscv: sifive_u: Add QSPI2 controller and connect an SD card
  hw/riscv: sifive_u: Change SIFIVE_U_GEM_IRQ to decimal value
  docs/system: Sort targets in alphabetical order
  docs/system: Add RISC-V documentation
  docs/system: riscv: Add documentation for sifive_u machine

 docs/system/riscv/sifive_u.rst | 336 +++++++++++++++++++++++++++++++
 docs/system/target-riscv.rst   |  72 +++++++
 docs/system/targets.rst        |  20 +-
 include/hw/riscv/sifive_u.h    |   9 +-
 include/hw/ssi/sifive_spi.h    |  47 +++++
 hw/block/m25p80.c              |  57 +++++-
 hw/riscv/sifive_u.c            |  91 +++++++++
 hw/ssi/sifive_spi.c            | 358 +++++++++++++++++++++++++++++++++
 hw/riscv/Kconfig               |   3 +
 hw/ssi/Kconfig                 |   4 +
 hw/ssi/meson.build             |   1 +
 11 files changed, 989 insertions(+), 9 deletions(-)
 create mode 100644 docs/system/riscv/sifive_u.rst
 create mode 100644 docs/system/target-riscv.rst
 create mode 100644 include/hw/ssi/sifive_spi.h
 create mode 100644 hw/ssi/sifive_spi.c

-- 
2.25.1