docs: platform: Update descriptions for qemu/sifive_u support

With QEMU v4.2 release that has improved the emulation fidelity
of 'sifive_u' machine, OpenSBI v0.4 / U-Boot v2019.10-rc1 / Linux
kernel v5.3-rc2 images built for the SiFive HiFive Unleashed board
can be used out of the box without any special hack.

Update our documents to mention 'qemu/sifive_u' platform should
only be used with QEMU v4.1 or before, and it will be dropped
sometime in the future release.

Going forward, 'sifive/fu540' platform can be used on both real
hardware and QEMU v4.2+ 'sifive_u' machine.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
This commit is contained in:
Bin Meng
2019-09-23 05:49:15 -07:00
committed by Anup Patel
parent 98ee15ca3a
commit 8853758268
2 changed files with 20 additions and 0 deletions

View File

@@ -4,6 +4,9 @@ The FU540-C000 is the worlds first 4+1 64-bit RISC-V SoC from SiFive.
The HiFive Unleashed development platform is based on FU540-C000 and capable
of running Linux.
With QEMU v4.2 or above release, the 'sifive_u' machine can be used to test
OpenSBI image built for the real hardware as well.
To build platform specific library and firmwares, provide the
*PLATFORM=sifive/fu540* parameter to the top level `make` command.
@@ -201,3 +204,12 @@ At U-Boot prompt execute the following boot command to boot Linux.
```
bootm ${kernel_addr_r} - ${fdt_addr_r}
```
QEMU Specific Instructions
--------------------------
If you want to test OpenSBI with QEMU 'sifive_u' machine, please follow the
same instructions above, with the exception of not passing FW_PAYLOAD_FDT_PATH.
This is because QEMU generates a device tree blob on the fly based on the
command line parameters and it's compatible with the one used in the upstream
Linux kernel.